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Sample records for arctic climate system

  1. Arctic Climate Systems Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ivey, Mark D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Robinson, David G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Boslough, Mark B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Backus, George A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Peterson, Kara J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); van Bloemen Waanders, Bart G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Swiler, Laura Painton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Desilets, Darin Maurice [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Reinert, Rhonda Karen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    This study began with a challenge from program area managers at Sandia National Laboratories to technical staff in the energy, climate, and infrastructure security areas: apply a systems-level perspective to existing science and technology program areas in order to determine technology gaps, identify new technical capabilities at Sandia that could be applied to these areas, and identify opportunities for innovation. The Arctic was selected as one of these areas for systems level analyses, and this report documents the results. In this study, an emphasis was placed on the arctic atmosphere since Sandia has been active in atmospheric research in the Arctic since 1997. This study begins with a discussion of the challenges and benefits of analyzing the Arctic as a system. It goes on to discuss current and future needs of the defense, scientific, energy, and intelligence communities for more comprehensive data products related to the Arctic; assess the current state of atmospheric measurement resources available for the Arctic; and explain how the capabilities at Sandia National Laboratories can be used to address the identified technological, data, and modeling needs of the defense, scientific, energy, and intelligence communities for Arctic support.

  2. Arctic melt ponds and energy balance in the climate system

    Science.gov (United States)

    Sudakov, Ivan

    2017-02-01

    Elements of Earth's cryosphere, such as the summer Arctic sea ice pack, are melting at precipitous rates that have far outpaced the projections of large scale climate models. Understanding key processes, such as the evolution of melt ponds that form atop Arctic sea ice and control its optical properties, is crucial to improving climate projections. These types of critical phenomena in the cryosphere are of increasing interest as the climate system warms, and are crucial for predicting its stability. In this paper, we consider how geometrical properties of melt ponds can influence ice-albedo feedback and how it can influence the equilibria in the energy balance of the planet.

  3. The Arctic Ocean in the global climate system (review)

    OpenAIRE

    Alekseev,G. V./Ivanov,V. V./Zakharov,V. F./Yanes,A. V.

    1996-01-01

    The oceanic portion of the Arctic climate system has a strong influence on global climate change. This is because, first, the Arctic Ocean can change its capacity for redistribution of solar heat in consequence of the changes of thermohaline structure of the upper layer and the sea ice area on its surface, second; the vertical oceanic circulation in high latitudes is very sensitive to changes of the fresh water balance on the ocean surface that can cause a profound effect on the production of...

  4. Arctic melt ponds and bifurcations in the climate system

    CERN Document Server

    Sudakov, Ivan; Golden, Kenneth M

    2014-01-01

    Understanding how sea ice melts is critical to climate projections. In the Arctic, melt ponds that develop on the surface of sea ice floes during the late spring and summer largely determine their albedo $-$ a key parameter in climate modeling. Here we explore the possibility of a simple sea ice climate model passing through a bifurcation point $-$ an irreversible critical threshold as the system warms, by incorporating geometric information about melt pond evolution. This study is based on a nonlinear phase transition model for melt ponds, and bifurcation analysis of a simple climate model with ice - albedo feedback as the key mechanism driving the system to a potential bifurcation point.

  5. Collaborative Research: Towards Advanced Understanding and Predictive Capability of Climate Change in the Arctic using a High-Resolution Regional Arctic Climate System Model

    Energy Technology Data Exchange (ETDEWEB)

    Lettenmaier, Dennis P

    2013-04-08

    Primary activities are reported in these areas: climate system component studies via one-way coupling experiments; development of the Regional Arctic Climate System Model (RACM); and physical feedback studies focusing on changes in Arctic sea ice using the fully coupled model.

  6. Influence of Sea Ice on Arctic Marine Sulfur Biogeochemistry in the Community Climate System Model

    Energy Technology Data Exchange (ETDEWEB)

    Deal, Clara [Univ. of Alaska, Fairbanks, AL (United States); Jin, Meibing [Univ. of Alaska, Fairbanks, AL (United States)

    2013-06-30

    Global climate models (GCMs) have not effectively considered how responses of arctic marine ecosystems to a warming climate will influence the global climate system. A key response of arctic marine ecosystems that may substantially influence energy exchange in the Arctic is a change in dimethylsulfide (DMS) emissions, because DMS emissions influence cloud albedo. This response is closely tied to sea ice through its impacts on marine ecosystem carbon and sulfur cycling, and the ice-albedo feedback implicated in accelerated arctic warming. To reduce the uncertainty in predictions from coupled climate simulations, important model components of the climate system, such as feedbacks between arctic marine biogeochemistry and climate, need to be reasonably and realistically modeled. This research first involved model development to improve the representation of marine sulfur biogeochemistry simulations to understand/diagnose the control of sea-ice-related processes on the variability of DMS dynamics. This study will help build GCM predictions that quantify the relative current and possible future influences of arctic marine ecosystems on the global climate system. Our overall research objective was to improve arctic marine biogeochemistry in the Community Climate System Model (CCSM, now CESM). Working closely with the Climate Ocean Sea Ice Model (COSIM) team at Los Alamos National Laboratory (LANL), we added 1 sea-ice algae and arctic DMS production and related biogeochemistry to the global Parallel Ocean Program model (POP) coupled to the LANL sea ice model (CICE). Both CICE and POP are core components of CESM. Our specific research objectives were: 1) Develop a state-of-the-art ice-ocean DMS model for application in climate models, using observations to constrain the most crucial parameters; 2) Improve the global marine sulfur model used in CESM by including DMS biogeochemistry in the Arctic; and 3) Assess how sea ice influences DMS dynamics in the arctic marine

  7. Evaluation of the Regional Arctic System Model (RASM) - Process-resolving Arctic Climate Simulation

    Science.gov (United States)

    Maslowski, Wieslaw

    2016-04-01

    The Regional Arctic System Model (RASM) has been developed to better understand the past and present operation of Arctic System at process scale and to predict its change at time scales from days to decades, in support of the US environmental assessment and prediction needs. RASM is a limited-area, fully coupled ice-ocean-atmosphere-land model that uses the Community Earth System Model (CESM) framework. It includes the Weather Research and Forecasting (WRF) model, the LANL Parallel Ocean Program (POP) and Community Ice Model (CICE) and the Variable Infiltration Capacity (VIC) land hydrology model. The ocean and sea ice models used in RASM are regionally configured versions of those used in CESM, while WRF replaces the Community Atmospheric Model (CAM). In addition, a streamflow routing (RVIC) model was recently implemented in RASM to transport the freshwater flux from the land surface to the Arctic Ocean. The model domain is configured at an eddy-permitting resolution of 1/12° (or ~9km) for the ice-ocean and 50 km for the atmosphere-land model components. It covers the entire Northern Hemisphere marine cryosphere, terrestrial drainage to the Arctic Ocean and its major inflow and outflow pathways, with optimal extension into the North Pacific / Atlantic to model the passage of cyclones into the Arctic. In addition, a 1/48° (or ~2.4km) grid for the ice-ocean model components has been recently configured. All RASM components are coupled at high frequency (currently at 20-minute intervals) to allow realistic representation of inertial interactions among the model components. In addition to an overview of RASM technical details, model results are presented from both fully coupled and subsets of RASM, where the atmospheric and land components are replaced with prescribed realistic atmospheric reanalysis data to evaluate model skill in representing seasonal climatology as well as interannual and multidecadal climate variability. Selected physical processes and resulting

  8. The expedition ARCTIC `96 of RV `Polarstern` (ARK XII) with the Arctic Climate System Study (ACSYS). Cruise report; Die Expedition ARCTIC `96 des FS `Polarstern` (ARK XII) mit der Arctic Climate System Study (ACSYS). Fahrtbericht

    Energy Technology Data Exchange (ETDEWEB)

    Augstein, E.

    1997-11-01

    The multinational expedition ARCTIC `96 was carried out jointly by two ships, the German RV POLARSTERN and the Swedish RV ODEN. The research programme was developed by scientists from British, Canadian, Finish, German, Irish, Norwegian, Russian, Swedish and US American research institutions and universities. The physical programme on POLARSTERN was primarily designed to foster the Arctic Climte System Study (ACSYS) in the framework of the World Climate Research Programme (WCRP). Investigations during the recent years have provided substantial evidence that the Arctic Ocean and the adjacent shelf seas play a significant role in the thermohaline oceanic circulation and may therefore have a distinct influence on global climate. Consequently the main ACSYS goals are concerned with studies of the governing oceanic, atmospheric and hydrological processes in the entire Arctic region. (orig.) [Deutsch] Die Expedition ARCTIC `96 wurde von zwei Forschungsschiffen, der deutschen POLARSTERN und der schwedischen ODEN unter Beteiligung von Wissenschaftlern und Technikern aus Deutschland, Finnland, Grossbritannien, Irland, Kanada, Norwegen, Russland, Schweden und den Vereinigten Staaten von Amerika durchgefuehrt. Die physikalischen Projekte auf der POLARSTERN dienten ueberwiegend der Unterstuetzung der Arctic Climate System Study (ACSYS) des Weltklimaforschungsprogramms, die auf die Erforschung der vorherrschenden ozeanischen, atmosphaerischen, kryosphaerischen und hydrologischen Prozesse der Arktisregion ausgerichtet ist. (orig.)

  9. Collaborative Proposal: Improving Decadal Prediction of Arctic Climate Variability and Change Using a Regional Arctic System Model (RASM)

    Energy Technology Data Exchange (ETDEWEB)

    Maslowski, Wieslaw [Naval Postgraduate School, Monterey, CA (United States)

    2016-10-17

    This project aims to develop, apply and evaluate a regional Arctic System model (RASM) for enhanced decadal predictions. Its overarching goal is to advance understanding of the past and present states of arctic climate and to facilitate improvements in seasonal to decadal predictions. In particular, it will focus on variability and long-term change of energy and freshwater flows through the arctic climate system. The project will also address modes of natural climate variability as well as extreme and rapid climate change in a region of the Earth that is: (i) a key indicator of the state of global climate through polar amplification and (ii) which is undergoing environmental transitions not seen in instrumental records. RASM will readily allow the addition of other earth system components, such as ecosystem or biochemistry models, thus allowing it to facilitate studies of climate impacts (e.g., droughts and fires) and of ecosystem adaptations to these impacts. As such, RASM is expected to become a foundation for more complete Arctic System models and part of a model hierarchy important for improving climate modeling and predictions.

  10. COLLABORATIVE RESEARCH: TOWARDS ADVANCED UNDERSTANDING AND PREDICTIVE CAPABILITY OF CLIMATE CHANGE IN THE ARCTIC USING A HIGH-RESOLUTION REGIONAL ARCTIC CLIMATE SYSTEM MODEL

    Energy Technology Data Exchange (ETDEWEB)

    Gutowski, William J.

    2013-02-07

    The motivation for this project was to advance the science of climate change and prediction in the Arctic region. Its primary goals were to (i) develop a state-of-the-art Regional Arctic Climate system Model (RACM) including high-resolution atmosphere, land, ocean, sea ice and land hydrology components and (ii) to perform extended numerical experiments using high performance computers to minimize uncertainties and fundamentally improve current predictions of climate change in the northern polar regions. These goals were realized first through evaluation studies of climate system components via one-way coupling experiments. Simulations were then used to examine the effects of advancements in climate component systems on their representation of main physics, time-mean fields and to understand variability signals at scales over many years. As such this research directly addressed some of the major science objectives of the BER Climate Change Research Division (CCRD) regarding the advancement of long-term climate prediction.

  11. Regional Arctic System Model (RASM): A Tool to Advance Understanding and Prediction of Arctic Climate Change at Process Scales

    Science.gov (United States)

    Maslowski, W.; Roberts, A.; Osinski, R.; Brunke, M.; Cassano, J. J.; Clement Kinney, J. L.; Craig, A.; Duvivier, A.; Fisel, B. J.; Gutowski, W. J., Jr.; Hamman, J.; Hughes, M.; Nijssen, B.; Zeng, X.

    2014-12-01

    The Arctic is undergoing rapid climatic changes, which are some of the most coordinated changes currently occurring anywhere on Earth. They are exemplified by the retreat of the perennial sea ice cover, which integrates forcing by, exchanges with and feedbacks between atmosphere, ocean and land. While historical reconstructions from Global Climate and Global Earth System Models (GC/ESMs) are in broad agreement with these changes, the rate of change in the GC/ESMs remains outpaced by observations. Reasons for that stem from a combination of coarse model resolution, inadequate parameterizations, unrepresented processes and a limited knowledge of physical and other real world interactions. We demonstrate the capability of the Regional Arctic System Model (RASM) in addressing some of the GC/ESM limitations in simulating observed seasonal to decadal variability and trends in the sea ice cover and climate. RASM is a high resolution, fully coupled, pan-Arctic climate model that uses the Community Earth System Model (CESM) framework. It uses the Los Alamos Sea Ice Model (CICE) and Parallel Ocean Program (POP) configured at an eddy-permitting resolution of 1/12° as well as the Weather Research and Forecasting (WRF) and Variable Infiltration Capacity (VIC) models at 50 km resolution. All RASM components are coupled via the CESM flux coupler (CPL7) at 20-minute intervals. RASM is an example of limited-area, process-resolving, fully coupled earth system model, which due to the additional constraints from lateral boundary conditions and nudging within a regional model domain facilitates detailed comparisons with observational statistics that are not possible with GC/ESMs. In this talk, we will emphasize the utility of RASM to understand sensitivity to variable parameter space, importance of critical processes, coupled feedbacks and ultimately to reduce uncertainty in arctic climate change projections.

  12. Globalising the Arctic Climate:

    DEFF Research Database (Denmark)

    Corry, Olaf

    2017-01-01

    This chapter uses an object-oriented approach to explore how the Arctic is being constituted as an object of global governance within an emerging ‘global polity’, partly through geoengineering plans and political visions ('imaginaries'). It suggests that governance objects—the socially constructe...... on world politics. The emergence of the Arctic climate as a potential target of governance provides a case in point. The Arctic climate is becoming globalised, pushing it up the political agenda but drawing it away from its local and regional context.......This chapter uses an object-oriented approach to explore how the Arctic is being constituted as an object of global governance within an emerging ‘global polity’, partly through geoengineering plans and political visions ('imaginaries'). It suggests that governance objects—the socially constructed...... targets of political operations and contestations—are not simple ‘issues’ or ‘problems’ given to actors to deal with. Governance-objects emerge and are constructed through science, technology and politics, and rather than slotting neatly into existing structures, they have their own structuring effects...

  13. Arctic sea ice and Eurasian climate: A review

    OpenAIRE

    Gao, Yongqi; Sun, Jianqi; Li, Fei; He, Shengping; SANDVEN, Stein; Yan, Qing; Zhang, Zhongshi; LOHMANN, Katja; KEENLYSIDE, Noel; Furevik, Tore; Suo, Lingling

    2014-01-01

    The Arctic plays a fundamental role in the climate system and has shown significant climate change in recent decades, including the Arctic warming and decline of Arctic sea-ice extent and thickness. In contrast to the Arctic warming and reduction of Arctic sea ice, Europe, East Asia and North America have experienced anomalously cold conditions, with record snowfall during recent years. In this paper, we review current understanding of the sea-ice impacts on the Eurasian climate. Paleo, obser...

  14. Regional Arctic System Model (RASM): A Tool to Address the U.S. Priorities and Advance Capabilities for Arctic Climate Modeling and Prediction

    Science.gov (United States)

    Maslowski, W.; Roberts, A.; Cassano, J. J.; Gutowski, W. J., Jr.; Nijssen, B.; Osinski, R.; Zeng, X.; Brunke, M.; Duvivier, A.; Hamman, J.; Hossainzadeh, S.; Hughes, M.; Seefeldt, M. W.

    2015-12-01

    The Arctic is undergoing some of the most coordinated rapid climatic changes currently occurring anywhere on Earth, including the retreat of the perennial sea ice cover, which integrates forcing by, exchanges with and feedbacks between atmosphere, ocean and land. While historical reconstructions from Earth System Models (ESMs) are in broad agreement with these changes, the rate of change in ESMs generally remains outpaced by observations. Reasons for that relate to a combination of coarse resolution, inadequate parameterizations, under-represented processes and a limited knowledge of physical interactions. We demonstrate the capability of the Regional Arctic System Model (RASM) in addressing some of the ESM limitations in simulating observed variability and trends in arctic surface climate. RASM is a high resolution, pan-Arctic coupled climate model with the sea ice and ocean model components configured at an eddy-permitting resolution of 1/12o and the atmosphere and land hydrology model components at 50 km resolution, which are all coupled at 20-minute intervals. RASM is an example of limited-area, process-resolving, fully coupled ESM, which due to the constraints from boundary conditions facilitates detailed comparisons with observational statistics that are not possible with ESMs. The overall goal of RASM is to address key requirements published in the Navy Arctic Roadmap: 2014-2030 and in the Implementation Plan for the National Strategy for the Arctic Region, regarding the need for advanced modeling capabilities for operational forecasting and strategic climate predictions through 2030. The main science objectives of RASM are to advance understanding and model representation of critical physical processes and feedbacks of importance to sea ice thickness and area distribution. RASM results are presented to quantify relative contributions by (i) resolved processes and feedbacks as well as (ii) sensitivity to space dependent sub-grid parameterizations to better

  15. How does climate change influence Arctic mercury?

    Science.gov (United States)

    Stern, Gary A; Macdonald, Robie W; Outridge, Peter M; Wilson, Simon; Chételat, John; Cole, Amanda; Hintelmann, Holger; Loseto, Lisa L; Steffen, Alexandra; Wang, Feiyue; Zdanowicz, Christian

    2012-01-01

    Recent studies have shown that climate change is already having significant impacts on many aspects of transport pathways, speciation and cycling of mercury within Arctic ecosystems. For example, the extensive loss of sea-ice in the Arctic Ocean and the concurrent shift from greater proportions of perennial to annual types have been shown to promote changes in primary productivity, shift foodweb structures, alter mercury methylation and demethylation rates, and influence mercury distribution and transport across the ocean-sea-ice-atmosphere interface (bottom-up processes). In addition, changes in animal social behavior associated with changing sea-ice regimes can affect dietary exposure to mercury (top-down processes). In this review, we address these and other possible ramifications of climate variability on mercury cycling, processes and exposure by applying recent literature to the following nine questions; 1) What impact has climate change had on Arctic physical characteristics and processes? 2) How do rising temperatures affect atmospheric mercury chemistry? 3) Will a decrease in sea-ice coverage have an impact on the amount of atmospheric mercury deposited to or emitted from the Arctic Ocean, and if so, how? 4) Does climate affect air-surface mercury flux, and riverine mercury fluxes, in Arctic freshwater and terrestrial systems, and if so, how? 5) How does climate change affect mercury methylation/demethylation in different compartments in the Arctic Ocean and freshwater systems? 6) How will climate change alter the structure and dynamics of freshwater food webs, and thereby affect the bioaccumulation of mercury? 7) How will climate change alter the structure and dynamics of marine food webs, and thereby affect the bioaccumulation of marine mercury? 8) What are the likely mercury emissions from melting glaciers and thawing permafrost under climate change scenarios? and 9) What can be learned from current mass balance inventories of mercury in the Arctic? The

  16. SubArctic Oceans and Global Climate

    Science.gov (United States)

    Rhines, P. B.

    2004-12-01

    uptake of anthropogenic carbon from the atmosphere sensitive to changes in the gyre circulations and MOC? How does the oceanic circulation participate in the remarkably `tall' subArctic/Arctic climate system, that reaches up through the atmospheric storm tracks to the stratosphere? These questions are tied closely to the Arctic Basin itself, where thermodynamic warming competes with wind-induced anomalies and trends in sea-ice cover. The Arctic-SubArctic Ocean Flux (ASOF) program aims to narrow the uncertainty implicit in these questions, constructing a bridge between Arctic Ocean circulation dynamics and the dynamics of the subtropical Atlantic and Pacific. By defining a series of both flux array measurements and process studies, ASOF can illuminate what has long been aqua et glacies incognita.

  17. Time varying arctic climate change amplification

    Energy Technology Data Exchange (ETDEWEB)

    Chylek, Petr [Los Alamos National Laboratory; Dubey, Manvendra K [Los Alamos National Laboratory; Lesins, Glen [DALLHOUSIE U; Wang, Muyin [NOAA/JISAO

    2009-01-01

    During the past 130 years the global mean surface air temperature has risen by about 0.75 K. Due to feedbacks -- including the snow/ice albedo feedback -- the warming in the Arctic is expected to proceed at a faster rate than the global average. Climate model simulations suggest that this Arctic amplification produces warming that is two to three times larger than the global mean. Understanding the Arctic amplification is essential for projections of future Arctic climate including sea ice extent and melting of the Greenland ice sheet. We use the temperature records from the Arctic stations to show that (a) the Arctic amplification is larger at latitudes above 700 N compared to those within 64-70oN belt, and that, surprisingly; (b) the ratio of the Arctic to global rate of temperature change is not constant but varies on the decadal timescale. This time dependence will affect future projections of climate changes in the Arctic.

  18. Building Materials in Arctic Climate

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede

    2005-01-01

    Building in the artic requires special attention on the appropriateness of building materials. The harsh climate makes execution difficult and sets unusual requirements for the pure material properties. In addition, there is a lack of choice of good, natural building materials in the arctic....... This results in high transport costs. The building materials situation in Greenland may potentially be improved by intensifying the reuse of building materials or by promoting the local production of building materials....

  19. Recent advances in understanding the Arctic climate system state and change from a sea ice perspective: a review

    Directory of Open Access Journals (Sweden)

    R. Döscher

    2014-04-01

    Full Text Available The Arctic sea ice is the central and essential component of the Arctic climate system. The depletion and areal decline of the Arctic sea ice cover, observed since the 1970's, have accelerated after the millennium shift. While a relationship to global warming is evident and is underpinned statistically, the mechanisms connected to the sea ice reduction are to be explored in detail. Sea ice erodes both from the top and from the bottom. Atmosphere, sea ice and ocean processes interact in non-linear ways on various scales. Feedback mechanisms lead to an Arctic amplification of the global warming system. The amplification is both supported by the ice depletion and is at the same time accelerating the ice reduction. Knowledge of the mechanisms connected to the sea ice decline has grown during the 1990's and has deepened when the acceleration became clear in the early 2000's. Record summer sea ice extents in 2002, 2005, 2007 and 2012 provided additional information on the mechanisms. This article reviews recent progress in understanding of the sea ice decline. Processes are revisited from an atmospheric, ocean and sea ice perspective. There is strong evidence for decisive atmospheric changes being the major driver of sea ice change. Feedbacks due to reduced ice concentration, surface albedo and thickness allow for additional local atmosphere and ocean influences and self-supporting feedbacks. Large scale ocean influences on the Arctic Ocean hydrology and circulation are highly evident. Northward heat fluxes in the ocean are clearly impacting the ice margins, especially in the Atlantic sector of the Arctic. Only little indication exists for a direct decisive influence of the warming ocean on the overall sea ice cover, due to an isolating layer of cold and fresh water underneath the sea ice.

  20. Arctic and boreal ecosystems of western North America as components of the climate system

    Science.gov (United States)

    Chapin, F. S.; McGuire, A.D.; Randerson, J.; Pielke, R.; Baldocchi, D.; Hobbie, S.E.; Roulet, Nigel; Eugster, W.; Kasischke, E.; Rastetter, E.B.; Zimov, S.A.; Running, S.W.

    2000-01-01

    Synthesis of results from several Arctic and boreal research programmes provides evidence for the strong role of high-latitude ecosystems in the climate system. Average surface air temperature has increased 0.3??C per decade during the twentieth century in the western North American Arctic and boreal forest zones. Precipitation has also increased, but changes in soil moisture are uncertain. Disturbance rates have increased in the boreal forest; for example, there has been a doubling of the area burned in North America in the past 20 years. The disturbance regime in tundra may not have changed. Tundra has a 3-6-fold higher winter albedo than boreal forest, but summer albedo and energy partitioning differ more strongly among ecosystems within either tundra or boreal forest than between these two biomes. This indicates a need to improve our understanding of vegetation dynamics within, as well as between, biomes. If regional surface warming were to continue, changes in albedo and energy absorption would likely act as a positive feedback to regional warming due to earlier melting of snow and, over the long term, the northward movement of treeline. Surface drying and a change in dominance from mosses to vascular plants would also enhance sensible heat flux and regional warming in tundra. In the boreal forest of western North America, deciduous forests have twice the albedo of conifer forests in both winter and summer, 50-80% higher evapotranspiration, and therefore only 30-50% of the sensible heat flux of conifers in summer. Therefore, a warming-induced increase in fire frequency that increased the proportion of deciduous forests in the landscape, would act as a negative feedback to regional warming. Changes in thermokarst and the aerial extent of wetlands, lakes, and ponds would alter high-latitude methane flux. There is currently a wide discrepancy among estimates of the size and direction of CO2 flux between high-latitude ecosystems and the atmosphere. These

  1. Arctic Cities and Climate Change: A Geographic Impact Assessment

    Science.gov (United States)

    Shiklomanov, N. I.; Streletskiy, D. A.

    2014-12-01

    Arctic climate change is a concern for the engineering community, land-use planners and policy makers as it may have significant impacts on socio-economic development and human activities in the northern regions. A warmer climate has potential for a series of positive economic effects, such as development of maritime transportation, enhanced agricultural production and decrease in energy consumption. However, these potential benefits may be outwaited by negative impacts related to transportation accessibility and stability of existing infrastructure, especially in permafrost regions. Compared with the Arctic zones of other countries, the Russian Arctic is characterized by higher population, greater industrial development and urbanization. Arctic urban areas and associated industrial sites are the location of some of intense interaction between man and nature. However, while there is considerable research on various aspects of Arctic climate change impacts on human society, few address effects on Arctic cities and their related industries. This presentation overviews potential climate-change impacts on Russian urban environments in the Arctic and discusses methodology for addressing complex interactions between climatic, permafrost and socio-economic systems at the range of geographical scales. We also provide a geographic assessment of selected positive and negative climate change impacts affecting several diverse Russian Arctic cities.

  2. The Arctic CH4 sink and its implications for the permafrost carbon feedbacks to the global climate system

    Science.gov (United States)

    Juncher Jørgensen, Christian; Christiansen, Jesper; Mariager, Tue; Hugelius, Gustaf

    2016-04-01

    Using atmospheric methane (CH4), certain soil microbes are able to sustain their metabolism, and in turn remove this powerful greenhouse gas from the atmosphere. While the process of CH4 oxidation is a common feature in most natural and unmanaged ecosystems in temperate and boreal ecosystems, the interactions between soil physical properties and abiotic process drivers, net landscape exchange and spatial patterns across Arctic drylands remains highly uncertain. Recent works show consistent CH4 comsumption in upland dry tundra soils in Arctic and High Arctic environments (Christiansen et al., 2014, Biogeochemistry 122; Jørgensen et al., 2015, Nature Geoscience 8; Lau et al., 2015, The ISME Journal 9). In these dominantly dry or barren soil ecosystems, CH4 consumption has been observed to significantly exceed the amounts of CH4 emitted from adjacent wetlands. These observations point to a potentially important but largely overlooked component of the global soil-climate system interaction and a counterperspective to the conceptual understanding of the Arctic being a only a source of CH4. However, due to our limited knowledge of spatiotemporal occurrence of CH4 consumption across a wider range of the Arctic landscape we are left with substantial uncertainites and an overall unconstrained range estimate of this terrestrial CH4 sink and its potential effects on permafrost carbon feedback to the atmospheric CH4 concentration. To address this important knowledge gap and identify the most relevant spatial scaling parameters, we studied in situ CH4 net exchange across a large landscape transect on West Greenland. The transect representated soils formed from the dominant geological parent materials of dry upland tundra soils found in the ice-free land areas of Western Greenland, i.e. 1) granitic/gneissic parent material, 2) basaltic parent material and 3) sedimentary deposits. Results show that the dynamic variations in soil physical properties and soil hydrology exerts an

  3. Development of wind power production in arctic climate

    Energy Technology Data Exchange (ETDEWEB)

    Peltola, E.; Kaas, J.; Aarnio, E. [Kemijoki Oy (Finland)

    1998-10-01

    The project Development of wind power production in arctic climate is a direct continuation of Arctic wind energy research project, which started in 1989. The main topics in 1996-97 have been production development and commercialising the blade heating systems, development of operation and maintenance practices of arctic wind power plants, preparations for new wind farms and various network connection and energy system studies. Practical operations have taken place in Pyhaetunturi test power plant and in Paljasselkae and Lammashovi power plants, which are in commercial operation

  4. Carbon, Climate and Cameras: Showcasing Arctic research through multimedia storytelling

    Science.gov (United States)

    Tachihara, B. L.; Linder, C. A.; Holmes, R. M.

    2011-12-01

    In July 2011, Tachihara spent three weeks in the Siberian Arctic documenting The Polaris Project, an NSF-funded effort that brings together an international group of undergraduate students and research scientists to study Arctic systems. Using a combination of photography, video and interviews gathered during the field course, we produced a six-minute film focusing on the researchers' quest to track carbon as it moves from terrestrial upland areas into lakes, streams, rivers and eventually into the Arctic Ocean. The overall goal was to communicate the significance of Arctic science in the face of changing climate. Using a selection of clips from the 2011 video, we will discuss the advantages and challenges specific to using multimedia presentations to represent Arctic research, as well as science in general. The full video can be viewed on the Polaris website: http://www.thepolarisproject.org.

  5. Arctic ecosystem responses to a warming climate

    DEFF Research Database (Denmark)

    Mortensen, Lars O.

    sheet, loss of multiannual sea-ice and significant advances in snowmelt days. The biotic components of the arctic ecosystem have also been affected by the rapid changes in climate, for instance resulting in the collapse of the collared lemming cycle, advances in spring flowering and changes in the intra...... is frozen solid for the main part of the year. However, in recent decades, arctic temperatures have in-creased between two and three times that of the global averages, which have had a substantial impact on the physical environment of the arctic ecosystem, such as deglaciation of the Greenland inland ice......The Arctic embraces one of the simplest terrestrial ecosystems in the world and yet it covers roughly 11% of the world’s surface. Summer temperatures rarely exceed 10°C and most of the limited precipitation falls as snow. The landmasses are predominantly polar tundra, while the Arctic Ocean...

  6. Climate of the Arctic marine environment.

    Science.gov (United States)

    Walsh, John E

    2008-03-01

    The climate of the Arctic marine environment is characterized by strong seasonality in the incoming solar radiation and by tremendous spatial variations arising from a variety of surface types, including open ocean, sea ice, large islands, and proximity to major landmasses. Interannual and decadal-scale variations are prominent features of Arctic climate, complicating the distinction between natural and anthropogenically driven variations. Nevertheless, climate models consistently indicate that the Arctic is the most climatically sensitive region of the Northern Hemisphere, especially near the sea ice margins. The Arctic marine environment has shown changes over the past several decades, and these changes are part of a broader global warming that exceeds the range of natural variability over the past 1000 years. Record minima of sea ice coverage during the past few summers and increased melt from Greenland have important implications for the hydrographic regime of the Arctic marine environment. The recent changes in the atmosphere (temperature, precipitation, pressure), sea ice, and ocean appear to be a coordinated response to systematic variations of the large-scale atmospheric circulation, superimposed on a general warming that is likely associated with increasing greenhouse gases. The changes have been sufficiently large in some sectors (e.g., the Bering/Chukchi Seas) that consequences for marine ecosystems appear to be underway. Global climate models indicate an additional warming of several degrees Celsius in much of the Arctic marine environment by 2050. However, the warming is seasonal (largest in autumn and winter), spatially variable, and closely associated with further retreat of sea ice. Additional changes predicted for 2050 are a general decrease of sea level pressure (largest in the Bering sector) and an increase of precipitation. While predictions of changes in storminess cannot be made with confidence, the predicted reduction of sea ice cover will

  7. Pan-Arctic observations in GRENE Arctic Climate Change Research Project and its successor

    Science.gov (United States)

    Yamanouchi, Takashi

    2016-04-01

    We started a Japanese initiative - "Arctic Climate Change Research Project" - within the framework of the Green Network of Excellence (GRENE) Program, funded by the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT), in 2011. This Project targeted understanding and forecasting "Rapid Change of the Arctic Climate System and its Global Influences." Four strategic research targets are set by the Ministry: 1. Understanding the mechanism of warming amplification in the Arctic; 2. Understanding the Arctic climate system for global climate and future change; 3. Evaluation of the impacts of Arctic change on the weather and climate in Japan, marine ecosystems and fisheries; 4. Projection of sea ice distribution and Arctic sea routes. Through a network of universities and institutions in Japan, this 5-year Project involves more than 300 scientists from 39 institutions and universities. The National Institute of Polar Research (NIPR) works as the core institute and The Japan Agency for Marine- Earth Science and Technology (JAMSTEC) joins as the supporting institute. There are 7 bottom up research themes approved: the atmosphere, terrestrial ecosystems, cryosphere, greenhouse gases, marine ecology and fisheries, sea ice and Arctic sea routes and climate modeling, among 22 applications. The Project will realize multi-disciplinal study of the Arctic region and connect to the projection of future Arctic and global climatic change by modeling. The project has been running since the beginning of 2011 and in those 5 years pan-Arctic observations have been carried out in many locations, such as Svalbard, Russian Siberia, Alaska, Canada, Greenland and the Arctic Ocean. In particular, 95 GHz cloud profiling radar in high precision was established at Ny-Ålesund, Svalbard, and intensive atmospheric observations were carried out in 2014 and 2015. In addition, the Arctic Ocean cruises by R/V "Mirai" (belonging to JAMSTEC) and other icebreakers belonging to other

  8. Arctic Ocean shelf biogeochemical cycling under climate change

    Science.gov (United States)

    Bellerby, Richard; Silyakova, Anna; Slagstad, Dag

    2014-05-01

    Changes to Arctic Ocean biogeochemistry will result from a complex array of climate and chemical perturbations over the next decades. Changes to freshwater and nutrient supply through ice melt and continental runoff; warming of the ocean and an increasing ocean acidification through partial equilibrium with a rising anthropogenic CO2 load will change the nature of Arctic Ocean ecological and biogeochemical coupling. This is no more apparent on the shelf regions where there is strong influence from land sources of freshwater and total alkalinity. This presentation will document our combined approach of studying Arctic biogeochemical change through coupled observational, experimental and modelling campaigns. We have identified large changes in recent anthropogenic carbon transport to the Arctic and have characterised the associated regional and water mass ocean acidification. We have determined, through targeted Arctic pelagic ecosystem perturbations experiments, changes to ecosystem structure, succession and biogeochemical cycling under high CO2. Observations have been incorporated into regional, coupled physical-ecosystem-carbon biogeochemical models (informed at the boundaries by downscaled global earth system models) to develop scenarios of change in biogeochemical pathways. We have identified large regional variability in ocean acidification that is shown to impact on shelf biogeochemistry, ecosystems and climate feedbacks in the Arctic Ocean.

  9. Indicators of Arctic Sea Ice Bistability in Climate Model Simulations and Observations

    Science.gov (United States)

    2014-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Indicators of Arctic Sea Ice Bistability in Climate...possibility that the climate system supports multiple Arctic sea ice states that are relevant for the evolution of sea ice during the next several...the most relevant scalar quantities related to the hemisphere-scale Arctic sea ice cover that indicate the presence of bistability, as well as the

  10. Communicating Climate and Ecosystem Change in the Arctic

    Science.gov (United States)

    Soreide, N. N.; Overland, J. E.; Calder, J. A.; Rodionov, S.

    2005-12-01

    There is an explosion of interest in Northern Hemisphere climate, highlighting the importance of recent changes in the Arctic on mid-latitude climate and its impact on marine and terrestrial ecosystems. Traditional sea ice and tundra dominated arctic ecosystems are being reorganizing into warmer sub-arctic ecosystem types. Over the previous two years we have developed a comprehensive, near real-time arctic change detection protocol to track physical and biological changes for presentation on the web: http://www.arctic.noaa.gov/detect. The effort provides a continuous update to the Arctic Climate Impact Assessment (ACIA) Report, released in November 2004. Principles for the protocol include an accessible narrative style, scientifically credible and objective indicators, notes multiple uses for the information, acknowledges uncertainties, and balances having too many indicators-which leads to information overload-and too few-which does not capture the complexity of the system. Screening criteria include concreteness, public awareness, being understandable, availability of historical time series, and sensitivity. The site provides sufficient information for an individual to make their own assessment regarding the balance of the evidence for tracking change. The product provides an overview, recent news, links to many arctic websites, and highlights climate, global impacts, land and marine ecosystems, and human consequences. Since its inception a year ago, it has averaged about 9000 hits an day on the web, and is a major information source as determined by Google search. The future direction focuses on understanding the causes for change. In spring 2005 we also presented a near real-time ecological and climatic surveillance website for the Bering Sea: www.beringclimate.noaa.gov. The site provides up-to-date information which ties northward shifts of fish, invertebrate and marine mammal populations to physical changes in the Arctic. This site is more technical than the

  11. Arctic Freshwater Ice and Its Climatic Role

    OpenAIRE

    Prowse, Terry; Alfredsen, Knut; Beltaos, Spyros; Bonsal, Barrie; Duguay, Claude; Korhola, Atte; McNamara, Jim; Vincent, Warwick F.; Vuglinsky, Valery; Weyhenmeyer, Gesa A.

    2011-01-01

    Freshwater ice dominates the Arctic terrestrial environment and significantly impacts bio-physical and socio-economic systems. Unlike other major cryospheric components that either blanket large expanses (e.g., snow, permafrost, sea ice) or are concentrated in specific locations, lake and river ice are interwoven into the terrestrial landscape through major flow and storage networks. For instance, the headwaters of large ice-covered rivers extend well beyond the Arctic while many northern lak...

  12. Climate-derived tensions in Arctic security.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A.; Strickland, James Hassler

    2008-09-01

    Globally, there is no lack of security threats. Many of them demand priority engagement and there can never be adequate resources to address all threats. In this context, climate is just another aspect of global security and the Arctic just another region. In light of physical and budgetary constraints, new security needs must be integrated and prioritized with existing ones. This discussion approaches the security impacts of climate from that perspective, starting with the broad security picture and establishing how climate may affect it. This method provides a different view from one that starts with climate and projects it, in isolation, as the source of a hypothetical security burden. That said, the Arctic does appear to present high-priority security challenges. Uncertainty in the timing of an ice-free Arctic affects how quickly it will become a security priority. Uncertainty in the emergent extreme and variable weather conditions will determine the difficulty (cost) of maintaining adequate security (order) in the area. The resolution of sovereignty boundaries affects the ability to enforce security measures, and the U.S. will most probably need a military presence to back-up negotiated sovereignty agreements. Without additional global warming, technology already allows the Arctic to become a strategic link in the global supply chain, possibly with northern Russia as its main hub. Additionally, the multinational corporations reaping the economic bounty may affect security tensions more than nation-states themselves. Countries will depend ever more heavily on the global supply chains. China has particular needs to protect its trade flows. In matters of security, nation-state and multinational-corporate interests will become heavily intertwined.

  13. Arctic and Antarctic sea ice and climate

    Science.gov (United States)

    Barreira, S.

    2014-12-01

    Principal Components Analysis in T-Mode Varimax rotated was performed on Antarctic and Arctic monthly sea ice concentration anomalies (SICA) fields for the period 1979-2014, in order to investigate which are the main spatial characteristics of sea ice and its relationship with atmospheric circulation. This analysis provides 5 patterns of sea ice for inter-spring period and 3 patterns for summer-autumn for Antarctica (69,2% of the total variance) and 3 different patterns for summer-autumn and 3 for winter-spring season for the Arctic Ocean (67,8% of the total variance).Each of these patterns has a positive and negative phase. We used the Monthly Polar Gridded Sea Ice Concentrations database derived from satellite information generated by NASA Team algorithm. To understand the links between the SICA and climate trends, we extracted the mean pressure and, temperature field patterns for the months with high loadings (positive or negative) of the sea ice patterns that gave distinct atmospheric structures associated with each one. For Antarctica, the first SICA spatial winter-spring pattern in positive phase shows a negative SICA centre over the Drake Passage and north region of Bellingshausen and Weddell Seas together with another negative SICA centre over the East Indian Ocean. Strong positive centres over the rest of the Atlantic and Indian Oceans basins and the Amundsen Sea are also presented. A strong negative pressure anomaly covers most of the Antarctic Continent centered over the Bellingshausen Sea accompanied by three positive pressure anomalies in middle-latitudes. During recent years, the Arctic showed persistent associations of sea-ice and climate patterns principally during summer. Our strongest summer-autumn pattern in negative phase showed a marked reduction on SICA over western Arctic, primarily linked to an overall increase in Arctic atmospheric temperature most pronounced over the Beaufort, Chukchi and East Siberian Seas, and a positive anomaly of

  14. Arctic climate change in NORKLIMA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The NORKLIMA programme is the national Norwegian initiative on climate research established for the period 2004-2013. The programme seeks to generate key knowledge about climate trends, the impacts of climate change, and how Norway can adapt to these changes. The NORKLIMA programme also encompasses research on instruments and policies for reducing emissions. Large-scale Programmes As part of the effort to meet national research-policy priorities, the Research Council has established a special funding instrument called the Large-scale Programmes. This initiative is designed to build long-term knowledge in order to encourage innovation and enhance value creation as well as to help find solutions to important challenges facing society.(Author)

  15. ESPC Regional Arctic Prediction System

    Science.gov (United States)

    2014-09-30

    the Navy the capability to conduct short-term (1 week) to extended (2 weeks) coupled weather forecasts for the Arctic region. APPROACH To...sensitivity of the Arctic weather forecast to key numerical parameters; and 5) conduct extensive validation and verification of the coupled system and...SEP 2014 2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE ESPC Regional Arctic Prediction System 5a. CONTRACT

  16. Climate projection of extreme wind speed regime in the Arctic

    Science.gov (United States)

    Surkova, Galina; Sokolova, Larisa

    2016-04-01

    Extreme surface wind events over the Arctic (60-90N, 0-360 E) are studied for the modern climate and for its future possible changes on the base of ERA-Interim reanalysis data and CMIP5 scenario RCP8.5. Horizontal surface wind speed (10 m) probability distribution functions in every grid point of reanalysis and models data over the Arctic were evaluated as well as wind speed for 50, 95, 99, 99.9 percentiles (V0.50, V0.95, V0.99, V0.999). At first, changes of V0.50, V0.95, V0.99, V0.999 were studied on the base of ERA-Interim reanalysis for 1981-2010. Results showed regional inhomogenity of wind speed trend intensity. Also, analysis was made for zonal means and separate sectors of the Arctic. To study climate projection of high wind speed there were taken u,v values from CMIP5 numerical experiments for 1961-1990 (Historical) and 2081-2100 (RCP8.5). RCP8.5 scenario was chosen as having the most pronounced response in the climate system, which gave more statistical significance to the calculated trends. Modeled extreme wind speeds for the total Arctic and zonal means show rather good agreement with reanalysis data (compared for decades 1981-1990, 1991-2000). At the same time regional intermodel variability of wind speed is revealed. Trend of extreme surface wind speed in 21 century and for 2081-2100 over the Arctic are analyzed for each model. The study was supported by the Russian Science Foundation (project no. 14-37-00038).

  17. The Impact of Submarine Depth, Speed Sonar Systems on Arctic Sea-ice Draft Measurements

    Science.gov (United States)

    2015-04-21

    speed sonar systems on Arctic sea - ice draft measurements April 21, 2015 Reporting period: Oct 5, 2010- Sept 30, 2014 Prepared for: Office...TERM GOALS Arctic sea ice thickness is critical to geophysical research into climate change, shipping, biological productivity and other things...13. SUPPLEMENTARY NOTES 14. ABSTRACT Arctic sea ice thickness is critical to geophysical research into climate change, shipping, biological

  18. Climate change and the ecology and evolution of Arctic vertebrates

    DEFF Research Database (Denmark)

    Gilg, Olivier; Kovacs, Kit M.; Aars, J.

    2012-01-01

    Climate change is taking place more rapidly and severely in the Arctic than anywhere on the globe, exposing Arctic vertebrates to a host of impacts. Changes in the cryosphere dominate the physical changes that already affect these animals, but increasing air temperatures, changes in precipitation......, and ocean acidification will also affect Arctic ecosystems in the future. Adaptation via natural selection is problematic in such a rapidly changing environment. Adjustment via phenotypic plasticity is therefore likely to dominate Arctic vertebrate responses in the short term, and many such adjustments have...... immigration from the South, many Arctic vertebrates are expected to become increasingly threatened during this century....

  19. Warm Arctic—cold continents: climate impacts of the newly open Arctic Sea

    Directory of Open Access Journals (Sweden)

    James E. Overland

    2011-12-01

    Full Text Available Recent Arctic changes are likely due to coupled Arctic amplification mechanisms with increased linkage between Arctic climate and sub-Arctic weather. Historically, sea ice grew rapidly in autumn, a strong negative radiative feedback. But increased sea-ice mobility, loss of multi-year sea ice, enhanced heat storage in newly sea ice-free ocean areas, and modified wind fields form connected positive feedback processes. One-way shifts in the Arctic system are sensitive to the combination of episodic intrinsic atmospheric and ocean variability and persistent increasing greenhouse gases. Winter 2009/10 and December 2010 showed a unique connectivity between the Arctic and more southern weather patterns when the typical polar vortex was replaced by high geopotential heights over the central Arctic and low heights over mid-latitudes that resulted in record snow and low temperatures, a warm Arctic—cold continents pattern. The negative value of the winter (DJF 2009/10 North Atlantic Oscillation (NAO index associated with enhanced meridional winds was the lowest observed value since the beginning of the record in 1865. Wind patterns in December 2007 and 2008 also show an impact of warmer Arctic temperatures. A tendency for higher geopotential heights over the Arctic and enhanced meridional winds are physically consistent with continued loss of sea ice over the next 40 years. A major challenge is to understand the interaction of Arctic changes with climate patterns such as the NAO, Pacific North American and El Niño–Southern Oscillation.

  20. Can regional climate engineering save the summer Arctic sea ice?

    Science.gov (United States)

    Tilmes, S.; Jahn, Alexandra; Kay, Jennifer E.; Holland, Marika; Lamarque, Jean-Francois

    2014-02-01

    Rapid declines in summer Arctic sea ice extent are projected under high-forcing future climate scenarios. Regional Arctic climate engineering has been suggested as an emergency strategy to save the sea ice. Model simulations of idealized regional dimming experiments compared to a business-as-usual greenhouse gas emission simulation demonstrate the importance of both local and remote feedback mechanisms to the surface energy budget in high latitudes. With increasing artificial reduction in incoming shortwave radiation, the positive surface albedo feedback from Arctic sea ice loss is reduced. However, changes in Arctic clouds and the strongly increasing northward heat transport both counteract the direct dimming effects. A 4 times stronger local reduction in solar radiation compared to a global experiment is required to preserve summer Arctic sea ice area. Even with regional Arctic dimming, a reduction in the strength of the oceanic meridional overturning circulation and a shut down of Labrador Sea deep convection are possible.

  1. Arctic security in an age of climate change

    Energy Technology Data Exchange (ETDEWEB)

    Kraska, James (ed.)

    2013-03-01

    Publisher review: This book examines Arctic defense policy and military security from the perspective of all eight Arctic states. In light of climate change and melting ice in the Arctic Ocean, Canada, Russia, Denmark (Greenland), Norway and the United States, as well as Iceland, Sweden and Finland, are grappling with an emerging Arctic security paradigm. This volume brings together the world's most seasoned Arctic political-military experts from Europe and North America to analyze how Arctic nations are adapting their security postures to accommodate increased shipping, expanding naval presence, and energy and mineral development in the polar region. The book analyzes the ascent of Russia as the first 'Arctic superpower', the growing importance of polar security for NATO and the Nordic states, and the increasing role of Canada and the United States in the region.(Author)

  2. Biological response to climate change in the Arctic Ocean: The view from the past

    Science.gov (United States)

    Cronin, Thomas M.; Cronin, Matthew A.

    2017-01-01

    The Arctic Ocean is undergoing rapid climatic changes including higher ocean temperatures, reduced sea ice, glacier and Greenland Ice Sheet melting, greater marine productivity, and altered carbon cycling. Until recently, the relationship between climate and Arctic biological systems was poorly known, but this has changed substantially as advances in paleoclimatology, micropaleontology, vertebrate paleontology, and molecular genetics show that Arctic ecosystem history reflects global and regional climatic changes over all timescales and climate states (103–107 years). Arctic climatic extremes include 25°C hyperthermal periods during the Paleocene-Eocene (56–46 million years ago, Ma), Quaternary glacial periods when thick ice shelves and sea ice cover rendered the Arctic Ocean nearly uninhabitable, seasonally sea-ice-free interglacials and abrupt climate reversals. Climate-driven biological impacts included large changes in species diversity, primary productivity, species’ geographic range shifts into and out of the Arctic, community restructuring, and possible hybridization, but evidence is not sufficient to determine whether or when major episodes of extinction occurred.

  3. Climate change and zoonotic infections in the Russian Arctic

    Directory of Open Access Journals (Sweden)

    Boris Revich

    2012-07-01

    Full Text Available Climate change in the Russian Arctic is more pronounced than in any other part of the country. Between 1955 and 2000, the annual average air temperature in the Russian North increased by 1.2°C. During the same period, the mean temperature of upper layer of permafrost increased by 3°C. Climate change in Russian Arctic increases the risks of the emergence of zoonotic infectious diseases. This review presents data on morbidity rates among people, domestic animals and wildlife in the Russian Arctic, focusing on the potential climate related emergence of such diseases as tick-borne encephalitis, tularemia, brucellosis, leptospirosis, rabies, and anthrax.

  4. The Arctic Climate Modeling Program: Professional Development for Rural Teachers

    Science.gov (United States)

    Bertram, Kathryn Berry

    2010-01-01

    The Arctic Climate Modeling Program (ACMP) offered yearlong science, technology, engineering, and math (STEM) professional development to teachers in rural Alaska. Teacher training focused on introducing youth to workforce technologies used in Arctic research. Due to challenges in making professional development accessible to rural teachers, ACMP…

  5. Status of Wind-Diesel Applications in Arctic Climates: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Baring-Gould, I.; Corbus, D.

    2007-12-01

    The rising cost of diesel fuel and the environmental regulation for its transportation, use, and storage, combined with the clear impacts of increased arctic temperatures, is driving remote communities to examine alternative methods of providing power. Over the past few years, wind energy has been increasingly used to reduce diesel fuel consumption, providing economic, environmental, and security benefits to the energy supply of communities from Alaska to Antarctica. This summary paper describes the current state of wind-diesel systems, reviews the operation of wind-diesel plants in cold climates, discusses current research activities pertaining to these systems, and addresses their technical and commercial challenges. System architectures, dispatch strategies, and operating experience from a variety of wind-diesel systems in Alaska will be reviewed. Specific focus will also be given to the control of power systems with large amounts of wind generation and the complexities of replacing diesel engine waste heat with excess wind energy, a key factor in assessing power plants for retrofit. A brief overview of steps for assessing the viability of retrofitting diesel power systems with wind technologies will also be provided. Because of the large number of isolated diesel minigrids, the market for adding wind to these systems is substantial, specifically in arctic climates and on islands that rely on diesel-only power generation.

  6. Sensitivity of simulated regional Arctic climate to the choice of coupled model domain

    Directory of Open Access Journals (Sweden)

    Dmitry V. Sein

    2014-07-01

    Full Text Available The climate over the Arctic has undergone changes in recent decades. In order to evaluate the coupled response of the Arctic system to external and internal forcing, our study focuses on the estimation of regional climate variability and its dependence on large-scale atmospheric and regional ocean circulations. A global ocean–sea ice model with regionally high horizontal resolution is coupled to an atmospheric regional model and global terrestrial hydrology model. This way of coupling divides the global ocean model setup into two different domains: one coupled, where the ocean and the atmosphere are interacting, and one uncoupled, where the ocean model is driven by prescribed atmospheric forcing and runs in a so-called stand-alone mode. Therefore, selecting a specific area for the regional atmosphere implies that the ocean–atmosphere system can develop ‘freely’ in that area, whereas for the rest of the global ocean, the circulation is driven by prescribed atmospheric forcing without any feedbacks. Five different coupled setups are chosen for ensemble simulations. The choice of the coupled domains was done to estimate the influences of the Subtropical Atlantic, Eurasian and North Pacific regions on northern North Atlantic and Arctic climate. Our simulations show that the regional coupled ocean–atmosphere model is sensitive to the choice of the modelled area. The different model configurations reproduce differently both the mean climate and its variability. Only two out of five model setups were able to reproduce the Arctic climate as observed under recent climate conditions (ERA-40 Reanalysis. Evidence is found that the main source of uncertainty for Arctic climate variability and its predictability is the North Pacific. The prescription of North Pacific conditions in the regional model leads to significant correlation with observations, even if the whole North Atlantic is within the coupled model domain. However, the inclusion of the

  7. Adaptive strategies and life history characteristics in a warming climate: salmon in the Arctic?

    Science.gov (United States)

    Nielsen, Jennifer L.; Ruggerone, Gregory T.; Zimmerman, Christian E.

    2013-01-01

    In the warming Arctic, aquatic habitats are in flux and salmon are exploring their options. Adult Pacific salmon, including sockeye (Oncorhynchus nerka), coho (O. kisutch), Chinook (O. tshawytscha), pink (O. gorbuscha) and chum (O. keta) have been captured throughout the Arctic. Pink and chum salmon are the most common species found in the Arctic today. These species are less dependent on freshwater habitats as juveniles and grow quickly in marine habitats. Putative spawning populations are rare in the North American Arctic and limited to pink salmon in drainages north of Point Hope, Alaska, chum salmon spawning rivers draining to the northwestern Beaufort Sea, and small populations of chum and pink salmon in Canada’s Mackenzie River. Pacific salmon have colonized several large river basins draining to the Kara, Laptev and East Siberian seas in the Russian Arctic. These populations probably developed from hatchery supplementation efforts in the 1960’s. Hundreds of populations of Arctic Atlantic salmon (Salmo salar) are found in Russia, Norway and Finland. Atlantic salmon have extended their range eastward as far as the Kara Sea in central Russian. A small native population of Atlantic salmon is found in Canada’s Ungava Bay. The northern tip of Quebec seems to be an Atlantic salmon migration barrier for other North American stocks. Compatibility between life history requirements and ecological conditions are prerequisite for salmon colonizing Arctic habitats. Broad-scale predictive models of climate change in the Arctic give little information about feedback processes contributing to local conditions, especially in freshwater systems. This paper reviews the recent history of salmon in the Arctic and explores various patterns of climate change that may influence range expansions and future sustainability of salmon in Arctic habitats. A summary of the research needs that will allow informed expectation of further Arctic colonization by salmon is given.

  8. Interactions of arctic clouds, radiation, and sea ice in present-day and future climates

    Science.gov (United States)

    Burt, Melissa Ann

    The Arctic climate system involves complex interactions among the atmosphere, land surface, and the sea-ice-covered Arctic Ocean. Observed changes in the Arctic have emerged and projected climate trends are of significant concern. Surface warming over the last few decades is nearly double that of the entire Earth. Reduced sea-ice extent and volume, changes to ecosystems, and melting permafrost are some examples of noticeable changes in the region. This work is aimed at improving our understanding of how Arctic clouds interact with, and influence, the surface budget, how clouds influence the distribution of sea ice, and the role of downwelling longwave radiation (DLR) in climate change. In the first half of this study, we explore the roles of sea-ice thickness and downwelling longwave radiation in Arctic amplification. As the Arctic sea ice thins and ultimately disappears in a warming climate, its insulating power decreases. This causes the surface air temperature to approach the temperature of the relatively warm ocean water below the ice. The resulting increases in air temperature, water vapor and cloudiness lead to an increase in the surface downwelling longwave radiation, which enables a further thinning of the ice. This positive ice-insulation feedback operates mainly in the autumn and winter. A climate-change simulation with the Community Earth System Model shows that, averaged over the year, the increase in Arctic DLR is three times stronger than the increase in Arctic absorbed solar radiation at the surface. The warming of the surface air over the Arctic Ocean during fall and winter creates a strong thermal contrast with the colder surrounding continents. Sea-level pressure falls over the Arctic Ocean and the high-latitude circulation reorganizes into a shallow "winter monsoon." The resulting increase in surface wind speed promotes stronger surface evaporation and higher humidity over portions of the Arctic Ocean, thus reinforcing the ice-insulation feedback

  9. MOSAiC - Multidisciplinary drifting Observatory for the Study of Arctic Climate

    Science.gov (United States)

    Shupe, M.; Persson, O. P.; Tjernstrom, M. K.; Dethloff, K.

    2012-12-01

    The climate in the Arctic is changing faster than in other regions of the Earth, with near surface temperatures rising more than twice as fast as the global average and the perennial sea-ice cover shrinking fast, especially in summer. The Arctic is transitioning towards a new climate regime dominated by first year sea-ice. At the same time, the scientific understanding of processes and feedbacks causing this rapid change is poor and climate modeling in the Arctic remains problematic. Furthermore, the key physical processes and process-interactions in this new emerging Arctic system are likely different from those in the old system that was dominated by multi-year ice. Our understanding of this complex climate system, and ability to improve climate and weather models, is limited by the lack of observations in the extreme and remote central Arctic. Multi-year, detailed and comprehensive measurements, extending from the atmosphere through the sea-ice and into the ocean in the central Arctic Basin are needed to provide process-level understanding of the central Arctic climate system. To address this need, a manned, international drifting station will be installed in the young sea-ice of the western Arctic and follow the evolution of the ice pack as it proceeds through the transpolar drift towards the Fram Strait over the course of 1-2 years. The Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC), proposed to start in autumn 2017, will be guided by the broad theme: What are the causes and consequences of diminished Arctic sea-ice coverage? To address this theme requires a number of interdisciplinary investigations that target more specific science questions. *How do ongoing changes in the Arctic ice-ocean-atmosphere system drive heat and mass transfers of importance to climate and ecosystems? *What are the processes and feedbacks affecting sea ice cover, atmosphere-ocean stratification and energy budget in the Arctic? *Will an ice reduced

  10. Influence of altered low cloud parameterizations for seasonal variation of Arctic cloud amount on climate feedbacks

    Science.gov (United States)

    Kim, Yoojin; Choi, Yong-Sang; Kim, Baek-Min; Kim, Hyerim

    2016-09-01

    This study investigates the alteration of climate feedbacks due to overestimated wintertime low-level cloud amount bias over the Arctic region (60°N-90°N) in a climate model. The climate feedback was quantitatively examined through radiative kernels that are pre-calculated radiative responses of climate variables to doubling of carbon dioxide concentration in NCAR Community Atmosphere Model version 3 (CAM3). Climate models have various annual cycle of the Arctic cloud amount at the low-level particularly with large uncertainty in winter and CAM3 may tend to overestimate the Arctic low-level cloud. In this study, the seasonal variation of low-level cloud amount was modified by reducing the wintertime cloud amount by up to 35 %, and then compared with the original without seasonal variation. Thus, we investigate how that bias may affect climate feedbacks and the projections of future Arctic warming. The results show that the decrease in low-level cloud amount slightly affected the radiation budgets because of a small amount of incident solar insolation in winter, but considerably changed water vapor and temperature profiles. Consequently, the most distinctive was decreases in water vapor feedback and contribution of heat transport (by -0.20 and -0.55 W m-2 K-1, respectively) and increases in the lapse rate feedback and cloud feedback (by 0.13 and 0.58 W m-2 K-1, respectively) during winter in this model experiment. This study suggests that the change in Arctic cloud amount effectively reforms the contributions of individual climate feedbacks to Arctic climate system and leads to opposing effects on different feedbacks, which cancel out in the model.

  11. The Contribution to Arctic Climate Change from Countries in the Arctic Council

    Science.gov (United States)

    Schultz, T.; MacCracken, M. C.

    2013-12-01

    The conventional accounting frameworks for greenhouse gas (GHG) emissions used today, established under the Kyoto Protocol 25 years ago, exclude short lived climate pollutants (SLCPs), and do not include regional effects on the climate. However, advances in climate science now suggest that mitigation of SLCPs can reduce up to 50% of global warming by 2050. It has also become apparent that regions such as the Arctic have experienced a much greater degree of anthropogenic warming than the globe as a whole, and that efforts to slow this warming could benefit the larger effort to slow climate change around the globe. A draft standard for life cycle assessment (LCA), LEO-SCS-002, being developed under the American National Standards Institute process, has integrated the most recent climate science into a unified framework to account for emissions of all radiatively significant GHGs and SLCPs. This framework recognizes four distinct impacts to the oceans and climate caused by GHGs and SLCPs: Global Climate Change; Arctic Climate Change; Ocean Acidification; and Ocean Warming. The accounting for Arctic Climate Change, the subject of this poster, is based upon the Absolute Regional Temperature Potential, which considers the incremental change to the Arctic surface temperature resulting from an emission of a GHG or SLCP. Results are evaluated using units of mass of carbon dioxide equivalent (CO2e), which can be used by a broad array of stakeholders, including scientists, consumers, policy makers, and NGOs. This poster considers the contribution to Arctic Climate Change from emissions of GHGs and SLCPs from the eight member countries of the Arctic Council; the United States, Canada, Russia, Denmark, Finland, Iceland, Norway, and Sweden. Of this group of countries, the United States was the largest contributor to Arctic Climate Change in 2011, emitting 9600 MMT CO2e. This includes a gross warming of 11200 MMT CO2e (caused by GHGs, black and brown carbon, and warming effects

  12. Arctic Climate Variability and Trends from Satellite Observations

    Directory of Open Access Journals (Sweden)

    Xuanji Wang

    2012-01-01

    Full Text Available Arctic climate has been changing rapidly since the 1980s. This work shows distinctly different patterns of change in winter, spring, and summer for cloud fraction and surface temperature. Satellite observations over 1982–2004 have shown that the Arctic has warmed up and become cloudier in spring and summer, but cooled down and become less cloudy in winter. The annual mean surface temperature has increased at a rate of 0.34°C per decade. The decadal rates of cloud fraction trends are −3.4%, 2.3%, and 0.5% in winter, spring, and summer, respectively. Correspondingly, annually averaged surface albedo has decreased at a decadal rate of −3.2%. On the annual average, the trend of cloud forcing at the surface is −2.11 W/m2 per decade, indicating a damping effect on the surface warming by clouds. The decreasing sea ice albedo and surface warming tend to modulate cloud radiative cooling effect in spring and summer. Arctic sea ice has also declined substantially with decadal rates of −8%, −5%, and −15% in sea ice extent, thickness, and volume, respectively. Significant correlations between surface temperature anomalies and climate indices, especially the Arctic Oscillation (AO index, exist over some areas, implying linkages between global climate change and Arctic climate change.

  13. Arctic climate change: Greenhouse warming unleashed

    Science.gov (United States)

    Mauritsen, Thorsten

    2016-04-01

    Human activity alters the atmospheric composition, which leads to global warming. Model simulations suggest that reductions in emission of sulfur dioxide from Europe since the 1970s could have unveiled rapid Arctic greenhouse gas warming.

  14. Icy rivers heating up : Modelling hydrological impacts of climate change in the (sub)arctic

    OpenAIRE

    2003-01-01

    The Arctic is considered to be particularly sensitive to global climate change. Global warming will seriously affect the components of the water balance in northern regions and changes in precipitation and temperature have immediate as well as long term effects on river systems. The main goal of this thesis was to assess the potential impact of climate change on the water balance and river discharge in the (sub)arctic Usa basin, East-European Russia on an annual, monthly and 5-daily basis. Th...

  15. Energy use and indoor environment in new and existing dwellings in Arctic climates

    DEFF Research Database (Denmark)

    Kotol, Martin

    2014-01-01

    Buildings in Arctic climates require large amounts of heat to provide their occupants with a comfortable indoor environment. In recent years the intention to conserve energy has caused buildings in the Arctic (and worldwide) to become more insulated and airtight. The natural infiltration of build......Buildings in Arctic climates require large amounts of heat to provide their occupants with a comfortable indoor environment. In recent years the intention to conserve energy has caused buildings in the Arctic (and worldwide) to become more insulated and airtight. The natural infiltration...... investigated. For energy and indoor environmental reasons it is advisable that new airtight buildings be equipped with mechanical ventilation systems with heat recovery. Nevertheless, these systems when exposed to the Arctic winter climate face the risk of frost formation, which may put the ventilation system...... on indoor air quality performed in Sisimiut, Greenland. A questionnaire as part of the study found that over 30 % of respondents experience cold discomfort during winter months (i.e. cold floors, cold draft or too low indoor temperature), 35 % of the respondents reported frequent condensation on windows...

  16. Collaborative Research: Towards Advanced Understanding and Predictive Capability of Climate Change in the Arctic Using a High-Resolution Regional Arctic Climate Model

    Energy Technology Data Exchange (ETDEWEB)

    Cassano, John [Principal Investigator

    2013-06-30

    The primary research task completed for this project was the development of the Regional Arctic Climate Model (RACM). This involved coupling existing atmosphere, ocean, sea ice, and land models using the National Center for Atmospheric Research (NCAR) Community Climate System Model (CCSM) coupler (CPL7). RACM is based on the Weather Research and Forecasting (WRF) atmospheric model, the Parallel Ocean Program (POP) ocean model, the CICE sea ice model, and the Variable Infiltration Capacity (VIC) land model. A secondary research task for this project was testing and evaluation of WRF for climate-scale simulations on the large pan-Arctic model domain used in RACM. This involved identification of a preferred set of model physical parameterizations for use in our coupled RACM simulations and documenting any atmospheric biases present in RACM.

  17. Climate Change and Risk Management Challenges in the Arctic

    DEFF Research Database (Denmark)

    Jakobsen, Uffe

    Climate change or global warming results in melting ice in the Arctic, both inland and sea ice. This opens up opportunities of natural ressource extraction and possibilities of new shipping routes, that opens up opportunities for increased maritime activities. However, with these opportunies come...... possibilies of transborder risk management and partnership building....

  18. Icy rivers heating up : Modelling hydrological impacts of climate change in the (sub)arctic

    NARCIS (Netherlands)

    Linden, Sandra van der

    2003-01-01

    The Arctic is considered to be particularly sensitive to global climate change. Global warming will seriously affect the components of the water balance in northern regions and changes in precipitation and temperature have immediate as well as long term effects on river systems. The main goal of thi

  19. Arctic climate change in an ensemble of regional CORDEX simulations

    Directory of Open Access Journals (Sweden)

    Torben Koenigk

    2015-03-01

    Full Text Available Fifth phase Climate Model Intercomparison Project historical and scenario simulations from four global climate models (GCMs using the Representative Concentration Pathways greenhouse gas concentration trajectories RCP4.5 and RCP8.5 are downscaled over the Arctic with the regional Rossby Centre Atmosphere model (RCA. The regional model simulations largely reflect the circulation bias patterns of the driving global models in the historical period, indicating the importance of lateral and lower boundary conditions. However, local differences occur as a reduced winter 2-m air temperature bias over the Arctic Ocean and increased cold biases over land areas in RCA. The projected changes are dominated by a strong warming in the Arctic, exceeding 15°K in autumn and winter over the Arctic Ocean in RCP8.5, strongly increased precipitation and reduced sea-level pressure. Near-surface temperature and precipitation are linearly related in the Arctic. The wintertime inversion strength is reduced, leading to a less stable stratification of the Arctic atmosphere. The diurnal temperature range is reduced in all seasons. The large-scale change patterns are dominated by the surface and lateral boundary conditions so future response is similar in RCA and the driving global models. However, the warming over the Arctic Ocean is smaller in RCA; the warming over land is larger in winter and spring but smaller in summer. The future response of winter cloud cover is opposite in RCA and the GCMs. Precipitation changes in RCA are much larger during summer than in the global models and more small-scale change patterns occur.

  20. Climate change and the molecular ecology of Arctic marine mammals.

    Science.gov (United States)

    O'Corry-Crowe, Gregory

    2008-03-01

    Key to predicting likely consequences of future climate change for Arctic marine mammals is developing a detailed understanding of how these species use their environment today and how they were affected by past climate-induced environmental change. Genetic analyses are uniquely placed to address these types of questions. Molecular genetic approaches are being used to determine distribution and migration patterns, dispersal and breeding behavior, population structure and abundance over time, and the effects of past and present climate change in Arctic marine mammals. A review of published studies revealed that population subdivision, dispersal, and gene flow in Arctic marine mammals was shaped primarily by evolutionary history, geography, sea ice, and philopatry to predictable, seasonally available resources. A meta-analysis of data from 38 study units across seven species found significant relationships between neutral genetic diversity and population size and climate region, revealing that small, isolated subarctic populations tend to harbor lower diversity than larger Arctic populations. A few small populations had substantially lower diversity than others. By contrast, other small populations retain substantial neutral diversity despite extensive population declines in the 19th and 20th centuries. The evolutionary and contemporary perspectives gained from these studies can be used to model the consequences of different climate projections for individual behavior and population structure and ultimately individual fitness and population viability. Future research should focus on: (1) the use of ancient-DNA techniques to directly reconstruct population histories through the analysis of historical and prehistorical material, (2) the use of genomic technologies to identify, map, and survey genes that directly influence fitness, (3) long-term studies to monitor populations and investigate evolution in contemporary time, (4) further Arctic-wide, multispecies analyses

  1. Influence of climate model variability on projected Arctic shipping futures

    Science.gov (United States)

    Stephenson, Scott R.; Smith, Laurence C.

    2015-11-01

    Though climate models exhibit broadly similar agreement on key long-term trends, they have significant temporal and spatial differences due to intermodel variability. Such variability should be considered when using climate models to project the future marine Arctic. Here we present multiple scenarios of 21st-century Arctic marine access as driven by sea ice output from 10 CMIP5 models known to represent well the historical trend and climatology of Arctic sea ice. Optimal vessel transits from North America and Europe to the Bering Strait are estimated for two periods representing early-century (2011-2035) and mid-century (2036-2060) conditions under two forcing scenarios (RCP 4.5/8.5), assuming Polar Class 6 and open-water vessels with medium and no ice-breaking capability, respectively. Results illustrate that projected shipping viability of the Northern Sea Route (NSR) and Northwest Passage (NWP) depends critically on model choice. The eastern Arctic will remain the most reliably accessible marine space for trans-Arctic shipping by mid-century, while outcomes for the NWP are particularly model-dependent. Omitting three models (GFDL-CM3, MIROC-ESM-CHEM, and MPI-ESM-MR), our results would indicate minimal NWP potential even for routes from North America. Furthermore, the relative importance of the NSR will diminish over time as the number of viable central Arctic routes increases gradually toward mid-century. Compared to vessel class, climate forcing plays a minor role. These findings reveal the importance of model choice in devising projections for strategic planning by governments, environmental agencies, and the global maritime industry.

  2. The Arctic as a test case for an assessment of climate impacts on national security.

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Mark A.; Zak, Bernard Daniel; Backus, George A.; Ivey, Mark D.; Boslough, Mark Bruce Elrick

    2008-11-01

    The Arctic region is rapidly changing in a way that will affect the rest of the world. Parts of Alaska, western Canada, and Siberia are currently warming at twice the global rate. This warming trend is accelerating permafrost deterioration, coastal erosion, snow and ice loss, and other changes that are a direct consequence of climate change. Climatologists have long understood that changes in the Arctic would be faster and more intense than elsewhere on the planet, but the degree and speed of the changes were underestimated compared to recent observations. Policy makers have not yet had time to examine the latest evidence or appreciate the nature of the consequences. Thus, the abruptness and severity of an unfolding Arctic climate crisis has not been incorporated into long-range planning. The purpose of this report is to briefly review the physical basis for global climate change and Arctic amplification, summarize the ongoing observations, discuss the potential consequences, explain the need for an objective risk assessment, develop scenarios for future change, review existing modeling capabilities and the need for better regional models, and finally to make recommendations for Sandia's future role in preparing our leaders to deal with impacts of Arctic climate change on national security. Accurate and credible regional-scale climate models are still several years in the future, and those models are essential for estimating climate impacts around the globe. This study demonstrates how a scenario-based method may be used to give insights into climate impacts on a regional scale and possible mitigation. Because of our experience in the Arctic and widespread recognition of the Arctic's importance in the Earth climate system we chose the Arctic as a test case for an assessment of climate impacts on national security. Sandia can make a swift and significant contribution by applying modeling and simulation tools with internal collaborations as well as with

  3. Climate-driven regime shifts in Arctic marine benthos.

    Science.gov (United States)

    Kortsch, Susanne; Primicerio, Raul; Beuchel, Frank; Renaud, Paul E; Rodrigues, João; Lønne, Ole Jørgen; Gulliksen, Bjørn

    2012-08-28

    Climate warming can trigger abrupt ecosystem changes in the Arctic. Despite the considerable interest in characterizing and understanding the ecological impact of rapid climate warming in the Arctic, few long time series exist that allow addressing these research goals. During a 30-y period (1980-2010) of gradually increasing seawater temperature and decreasing sea ice cover in Svalbard, we document rapid and extensive structural changes in the rocky-bottom communities of two Arctic fjords. The most striking component of the benthic reorganization was an abrupt fivefold increase in macroalgal cover in 1995 in Kongsfjord and an eightfold increase in 2000 in Smeerenburgfjord. Simultaneous changes in the abundance of benthic invertebrates suggest that the macroalgae played a key structuring role in these communities. The abrupt, substantial, and persistent nature of the changes observed is indicative of a climate-driven ecological regime shift. The ecological processes thought to drive the observed regime shifts are likely to promote the borealization of these Arctic marine communities in the coming years.

  4. The fate of the Arctic seaweed Fucus distichus under climate change: an ecological niche modeling approach.

    Science.gov (United States)

    Jueterbock, Alexander; Smolina, Irina; Coyer, James A; Hoarau, Galice

    2016-03-01

    Rising temperatures are predicted to melt all perennial ice cover in the Arctic by the end of this century, thus opening up suitable habitat for temperate and subarctic species. Canopy-forming seaweeds provide an ideal system to predict the potential impact of climate-change on rocky-shore ecosystems, given their direct dependence on temperature and their key role in the ecological system. Our primary objective was to predict the climate-change induced range-shift of Fucus distichus, the dominant canopy-forming macroalga in the Arctic and subarctic rocky intertidal. More specifically, we asked: which Arctic/subarctic and cold-temperate shores of the northern hemisphere will display the greatest distributional change of F. distichus and how will this affect niche overlap with seaweeds from temperate regions? We used the program MAXENT to develop correlative ecological niche models with dominant range-limiting factors and 169 occurrence records. Using three climate-change scenarios, we projected habitat suitability of F. distichus - and its niche overlap with three dominant temperate macroalgae - until year 2200. Maximum sea surface temperature was identified as the most important factor in limiting the fundamental niche of F. distichus. Rising temperatures were predicted to have low impact on the species' southern distribution limits, but to shift its northern distribution limits poleward into the high Arctic. In cold-temperate to subarctic regions, new areas of niche overlap were predicted between F. distichus and intertidal macroalgae immigrating from the south. While climate-change threatens intertidal seaweeds in warm-temperate regions, seaweed meadows will likely flourish in the Arctic intertidal. Although this enriches biodiversity and opens up new seaweed-harvesting grounds, it will also trigger unpredictable changes in the structure and functioning of the Arctic intertidal ecosystem.

  5. Dynamics of Arctic and Sub-Arctic Climate and Atmospheric Circulation: Diagnosis of Mechanisms and Biases Using Data Assimilation

    Energy Technology Data Exchange (ETDEWEB)

    Eric T. DeWeaver

    2010-01-19

    This is the final report for DOE grant DE-FG02-07ER64434 to Eric DeWeaver at the University of Wisconsin-Madison. The overall goal of work performed under this grant is to enhance understanding of simulations of present-day climate and greenhouse gas-induced climate change. Enhanced understanding is desirable 1) as a prerequisite for improving simulations; 2) for assessing the credibility of model simulations and their usefulness as tools for decision support; and 3) as a means to identify robust behaviors which commonly occur over a wide range of models, and may yield insights regarding the dominant physical mechanisms which determine mean climate and produce climate change. A furthe objective is to investigate the use of data assimilation as a means for examining and correcting model biases. Our primary focus is on the Arctic, but the scope of the work was expanded to include the global climate system to the extent that research targets of opportunity present themselves. Research performed under the grant falls into five main research areas: 1) a study of data assimilation using an ensemble filter with the atmospheric circulation model of the National Center for Atmospheric Research, in which both conventional observations and observations of the refraction of radio waves from GPS satellites were used to constrain the atmospheric state of the model; 2) research on the likely future status of polar bears, in which climate model simluations were used to assess the effectiveness of climate change mitigation efforts in preserving the habitat of polar bears, now considered a threatened species under global warming; 3) as assessment of the credibility of Arctic sea ice thickness simulations from climate models; 4) An examination of the persistence and reemergence of Northern Hemisphere sea ice area anomalies in climate model simulations and in observations; 5) An examination of the roles played by changes in net radiation and surface relative humidity in determine the

  6.  Climate Change and the Arctic Discourses

    DEFF Research Database (Denmark)

    Bjørst, Lill Rastad

    2009-01-01

      It is now a fact that global warming and climate change are on the public agenda and will remain there for a long time to come. The Arctic has been portrayed as a thermometer for the world mostly because it is very vulnerable to the climatic changes and the subsequent consequences. Inuit are used...... as an example and included as the first witnesses to ‘the big catastrophe'. My hypothesis is that the newly emerging climate debate can establish an unexpected and unique political platform where Inuit can get influence on local as well as global questions. My investigating focus concerning these matters...... are politics, risk and cultural discourses....

  7. Trajectory of the Arctic as an integrated system.

    Science.gov (United States)

    Hinzman, Larry D; Deal, Clara J; McGuire, A David; Mernild, Sebastian H; Polyakov, Igor V; Walsh, John E

    2013-12-01

    Although much remains to be learned about the Arctic and its component processes, many of the most urgent scientific, engineering, and social questions can only be approached through a broader system perspective. Here, we address interactions between components of the Arctic system and assess feedbacks and the extent to which feedbacks (1) are now underway in the Arctic and (2) will shape the future trajectory of the Arctic system. We examine interdependent connections among atmospheric processes, oceanic processes, sea-ice dynamics, marine and terrestrial ecosystems, land surface stocks of carbon and water, glaciers and ice caps, and the Greenland ice sheet. Our emphasis on the interactions between components, both historical and anticipated, is targeted on the feedbacks, pathways, and processes that link these different components of the Arctic system. We present evidence that the physical components of the Arctic climate system are currently in extreme states, and that there is no indication that the system will deviate from this anomalous trajectory in the foreseeable future. The feedback for which the evidence of ongoing changes is most compelling is the surface albedo-temperature feedback, which is amplifying temperature changes over land (primarily in spring) and ocean (primarily in autumn-winter). Other feedbacks likely to emerge are those in which key processes include surface fluxes of trace gases, changes in the distribution of vegetation, changes in surface soil moisture, changes in atmospheric water vapor arising from higher temperatures and greater areas of open ocean, impacts of Arctic freshwater fluxes on the meridional overturning circulation of the ocean, and changes in Arctic clouds resulting from changes in water vapor content.

  8. Phenology and abundance in relation to climatic variation in a sub-arctic insect herbivore-mountain birch system.

    Science.gov (United States)

    Mjaaseth, Ragnhild R; Hagen, Snorre B; Yoccoz, Nigel G; Ims, Rolf A

    2005-08-01

    The two forest-defoliating geometrid moth species Operophtera brumata and Epirrita autumnata are known to exhibit different altitudinal distribution patterns in northern birch forests. One possible explanation for this is that altitudinal climatic variation differentially affects the performance of two species through mismatching larval and host plant phenology. We explored this hypothesis by investigating the relationship between larval phenology and leaf phenology of Betula pubescens, which is the main host plant of both moth species, along ten replicate altitudinal transects during two springs with contrasting climate in northern Norway. There was a distinct monotonous cline in host plant phenology with increasing altitude in both years of the study, but the development of the leaves were generally 14 days later in the first of the 2 years due to cold spring weather. We found that larval development of both species closely tracked host plant leaf phenology independent of altitude and year. However, at the time of sampling, E. autumnata was approximately one instar ahead of O. brumata at all altitudes, probably reflecting that E. autumnata has faster early instar growth than O. brumata. The abundance of O. brumata was lowest at the altitudinal forest-line, while E. autumnata was lowest near sea level. Our results do not indicate that the altitudinal distribution patterns of the two moth species is due to any phenological mismatch between larval and host plant phenology. We suggest rather that natural enemies at low altitudes limit larval survival and thus abundance of E. autumnata, while an early onset of winter at the forest limit reduces survival of late eclosing adults of O. brumata.

  9. Arctic climate change and oil spill risk analysis

    Institute of Scientific and Technical Information of China (English)

    William B. Samuels; David E. Amstutz; Heather A. Crowley

    2011-01-01

    The purpose of this project was to:1) describe the effects of climate change in the Arctic and its impact on circulation,2) describe hindcast data used in the Ocean Energy Management,Regulation and Enforcement (BOEMRE) Oil Spill Risk Analysis (OSRA) model,3)evaluate alternatives such as using forecast results in the OSRA model,and 4) recommend future studies.Effects of climate change on winds,sea ice,ocean circulation and river discharge in the Arctic and impacts on surface circulation can be evaluated only through a series of specially designed numerical experiments using highresolution coupled ice-ocean models to elucidate the sensitivity of the models to various parameterizations or forcings.The results of these experiments will suggest what mechanisms are most important in controlling model response and guide inferences on how OSRA may respond to different climate change scenarios.Climatological change in the Arctic could lead to drastic alterations of wind,sea ice cover and concentration,and surface current fields all of which would influence hypothetical oil spill trajectories.Because of the pace at which conditions are changing,BOEMRE needs to assess whether forecast ice/ocean model results might contain useful information for the purposes of calculating hypothetical oil spill trajectories.

  10. Past changes in Arctic terrestrial ecosystems, climate and UV radiation.

    Science.gov (United States)

    Callaghan, Terry V; Björn, Lars Olof; Chernov, Yuri; Chapin, Terry; Christensen, Torben R; Huntley, Brian; Ims, Rolf A; Johansson, Margareta; Jolly, Dyanna; Jonasson, Sven; Matveyeva, Nadya; Panikov, Nicolai; Oechel, Walter; Shaver, Gus

    2004-11-01

    At the last glacial maximum, vast ice sheets covered many continental areas. The beds of some shallow seas were exposed thereby connecting previously separated landmasses. Although some areas were ice-free and supported a flora and fauna, mean annual temperatures were 10-13 degrees C colder than during the Holocene. Within a few millennia of the glacial maximum, deglaciation started, characterized by a series of climatic fluctuations between about 18,000 and 11,400 years ago. Following the general thermal maximum in the Holocene, there has been a modest overall cooling trend, superimposed upon which have been a series of millennial and centennial fluctuations in climate such as the "Little Ice Age spanning approximately the late 13th to early 19th centuries. Throughout the climatic fluctuations of the last 150,000 years, Arctic ecosystems and biota have been close to their minimum extent within the most recent 10,000 years. They suffered loss of diversity as a result of extinctions during the most recent large-magnitude rapid global warming at the end of the last glacial stage. Consequently, Arctic ecosystems and biota such as large vertebrates are already under pressure and are particularly vulnerable to current and projected future global warming. Evidence from the past indicates that the treeline will very probably advance, perhaps rapidly, into tundra areas, as it did during the early Holocene, reducing the extent of tundra and increasing the risk of species extinction. Species will very probably extend their ranges northwards, displacing Arctic species as in the past. However, unlike the early Holocene, when lower relative sea level allowed a belt of tundra to persist around at least some parts of the Arctic basin when treelines advanced to the present coast, sea level is very likely to rise in future, further restricting the area of tundra and other treeless Arctic ecosystems. The negative response of current Arctic ecosystems to global climatic conditions

  11. Past Changes in Arctic Terrestrial Ecosystems, Climate and UV Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Callaghan, Terry V. [Abisko Scientific Research Station, Abisko (Sweden); Bjoern, Lars Olof [Lund Univ. (Sweden). Dept. of Cell and Organism Biology; Chernov, Yuri [Russian Academy of Sciences, Moscow (Russian Federation). A.N. Severtsov Inst. of Evolutionary Morphology and Animal Ecology] (and others)

    2004-11-01

    At the last glacial maximum, vast ice sheets covered many continental areas. The beds of some shallow seas were exposed thereby connecting previously separated landmasses. Although some areas were ice-free and supported a flora and fauna, mean annual temperatures were 10-13 deg C colder than during the Holocene. Within a few millennia of the glacial maximum, deglaciation started, characterized by a series of climatic fluctuations between about 18,000 and 11,400 years ago. Following the general thermal maximum in the Holocene, there has been a modest overall cooling trend, superimposed upon which have been a series of millennial and centennial fluctuations in climate such as the 'Little Ice Age' spanning approximately the late 13th to early 19th centuries. Throughout the climatic fluctuations of the last 150,000 years, Arctic ecosystems and biota have been close to their minimum extent within the most recent 10,000 years. They suffered loss of diversity as a result of extinctions during the most recent large-magnitude rapid global warming at the end of the last glacial stage. Consequently, Arctic ecosystems and biota such as large vertebrates are already under pressure and are particularly vulnerable to current and projected future global warming. Evidence from the past indicates that the treeline will very probably advance, perhaps rapidly, into tundra areas, as it did during the early Holocene, reducing the extent of tundra and increasing the risk of species extinction. Species will very probably extend their ranges northwards, displacing Arctic species as in the past. However, unlike the early Holocene, when lower relative sea level allowed a belt of tundra to persist around at least some parts of the Arctic basin when treelines advanced to the present coast, sea level is very likely to rise in future, further restricting the area of tundra and other treeless Arctic ecosystems. The negative response of current Arctic ecosystems to global climatic

  12. Surface towed electromagnetic system for mapping of subsea Arctic permafrost

    Science.gov (United States)

    Sherman, Dallas; Kannberg, Peter; Constable, Steven

    2017-02-01

    Sea level has risen globally since the late Pleistocene, resulting in permafrost-bearing coastal zones in the Arctic being submerged and subjected to temperature induced degradation. Knowing the extent of permafrost and how it changes over time is important for climate change predictions and for planning engineering activities in the Arctic environment. We developed a controlled source electromagnetic (CSEM) method to obtain information on the depth, thickness, and lateral extent of marine permafrost. To operate in shallow water we used a surface towed electric dipole-dipole CSEM system suitable for deployment from small boats. This system was used to map permafrost on the Arctic shelf offshore Prudhoe Bay, Alaska. Our results show significant lateral variability in the presence of permafrost, with the thickest layers associated with a large river outflow where freshwater influx seems to have a preserving effect on relict subsea permafrost.

  13. Development of Exhibit on Arctic Climate Change Called The Arctic: A Friend Acting Strangely Exhibition

    Energy Technology Data Exchange (ETDEWEB)

    Stauffer, Barbara W.

    2006-04-01

    The exhibition, The Arctic: A Friend Acting Strangely, was developed at the Smithsonian Institution’s National Museum of Natural History (NMNH) as a part of the museum’s Forces of Change exhibit series on global change. It opened to the public in Spring 2006, in conjunction with another Forces of Change exhibit on the Earth’s atmosphere called Change Is in the Air. The exhibit was a 2000 square-foot presentation that explored the forces and consequences of the changing Arctic as documented by scientists and native residents alike. Native peoples of the Arctic have always lived with year-to-year fluctuations in weather and ice conditions. In recent decades, they have witnessed that the climate has become unpredictable, the land and sea unfamiliar. An elder in Arctic Canada recently described the weather as uggianaqtuq —an Inuit word that can suggest strange, unexpected behavior, sometimes described as that of “a friend acting strangely.” Scientists too have been documenting dramatic changes in the Arctic. Air temperatures have warmed over most—though not all—of the Arctic since the 1950s; Arctic precipitation may have increased by as much as 8%; seasonal melting of the Greenland Ice Sheet has increased on average by 16% since 1979; polar-orbiting satellites have measured a 15¬–20% decline in sea ice extent since the 1970s; aircraft reconnaissance and ship observations show a steady decrease in sea ice since the 1950s. In response to this warming, plant distributions have begun to shift and animals are changing their migration routes. Some of these changes may have beneficial effects while others may bring hardship or have costly implications. And, many scientists consider arctic change to be a ‘bell-weather’ for large-scale changes in other regions of the world. The exhibition included text, photos artifacts, hands-on interactives and other exhibitry that illustrated the changes being documented by indigenous people and scientists alike.

  14. SEARCH: Study of Environmental Arctic Change--A System-scale, Cross-disciplinary Arctic Research Program

    Science.gov (United States)

    Shnoro, R. S.; Eicken, H.; Francis, J. A.; Scambos, T. A.; Schuur, E. A.; Straneo, F.; Wiggins, H. V.

    2013-12-01

    SEARCH is an interdisciplinary, interagency program that works with academic and government agency scientists and stakeholders to plan, conduct, and synthesize studies of Arctic change. Over the past three years, SEARCH has developed a new vision and mission, a set of prioritized cross-disciplinary 5-year goals, an integrated set of activities, and an organizational structure. The vision of SEARCH is to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic. SEARCH's 5-year science goals include: 1. Improve understanding, advance prediction, and explore consequences of changing Arctic sea ice. 2. Document and understand how degradation of near-surface permafrost will affect Arctic and global systems. 3. Improve predictions of future land-ice loss and impacts on sea level. 4. Analyze societal and policy implications of Arctic environmental change. Action Teams organized around each of the 5-year goals will serve as standing groups responsible for implementing specific goal activities. Members will be drawn from academia, different agencies and stakeholders, with a range of disciplinary backgrounds and perspectives. 'Arctic Futures 2050' scenarios tasks will describe plausible future states of the arctic system based on recent trajectories and projected changes. These scenarios will combine a range of data including climate model output, paleo-data, results from data synthesis and systems modeling, as well as expert scientific and traditional knowledge. Current activities include: - Arctic Observing Network (AON) - coordinating a system of atmospheric, land- and ocean-based environmental monitoring capabilities that will significantly advance our observations of arctic environmental conditions. - Arctic Sea Ice Outlook - an international effort that provides monthly summer reports synthesizing community estimates of the expected sea ice minimum. A newly-launched Sea Ice Prediction Network

  15. Climate Change and China as a Global Emerging Regulatory Sea Power in the Arctic Ocean

    DEFF Research Database (Denmark)

    Cassotta Pertoldi-Bianchi, Sandra; Hossain, Kamrul; Ren, Jingzheng;

    2015-01-01

    The impact of climate change in the Arctic Ocean such as ice melting and ice retreat facilitates natural resources extraction. Arctic fossil fuel becomes the drivers of geopolitical changes in the Arctic Ocean. Climate change facilitates natural resource extractions and increases competition...... between states and can result in tensions, even military ones. This article investigates through a political and legal analysis the role of China as an emerging regulatory sea power in the Arctic Ocean given its assertive “energy hungry country behaviour” in the Arctic Ocean. The United Nations Convention...... on the Law of the Sea (UNCLOS) and the Arctic Council (AC) are taken into consideration under climate change effects, to assess how global legal frameworks and institutions can deal with China’s strategy in the Arctic Ocean. China’s is moving away from its role as “humble power” to one of “informal...

  16. Arctic marine mammals and climate change: impacts and resilience.

    Science.gov (United States)

    Moore, Sue E; Huntington, Henry P

    2008-03-01

    Evolutionary selection has refined the life histories of seven species (three cetacean [narwhal, beluga, and bowhead whales], three pinniped [walrus, ringed, and bearded seals], and the polar bear) to spatial and temporal domains influenced by the seasonal extremes and variability of sea ice, temperature, and day length that define the Arctic. Recent changes in Arctic climate may challenge the adaptive capability of these species. Nine other species (five cetacean [fin, humpback, minke, gray, and killer whales] and four pinniped [harp, hooded, ribbon, and spotted seals]) seasonally occupy Arctic and subarctic habitats and may be poised to encroach into more northern latitudes and to remain there longer, thereby competing with extant Arctic species. A synthesis of the impacts of climate change on all these species hinges on sea ice, in its role as: (1) platform, (2) marine ecosystem foundation, and (3) barrier to non-ice-adapted marine mammals and human commercial activities. Therefore, impacts are categorized for: (1) ice-obligate species that rely on sea ice platforms, (2) ice-associated species that are adapted to sea ice-dominated ecosystems, and (3) seasonally migrant species for which sea ice can act as a barrier. An assessment of resilience is far more speculative, as any number of scenarios can be envisioned, most of them involving potential trophic cascades and anticipated human perturbations. Here we provide resilience scenarios for the three ice-related species categories relative to four regions defined by projections of sea ice reductions by 2050 and extant shelf oceanography. These resilience scenarios suggest that: (1) some populations of ice-obligate marine mammals will survive in two regions with sea ice refugia, while other stocks may adapt to ice-free coastal habitats, (2) ice-associated species may find suitable feeding opportunities within the two regions with sea ice refugia and, if capable of shifting among available prey, may benefit from

  17. Changes in Arctic and Antarctic Sea Ice as a Microcosm of Global Climate Change

    Science.gov (United States)

    Parkinson, Claire L.

    2014-01-01

    Polar sea ice is a key element of the climate system and has now been monitored through satellite observations for over three and a half decades. The satellite observations reveal considerable information about polar ice and its changes since the late 1970s, including a prominent downward trend in Arctic sea ice coverage and a much lesser upward trend in Antarctic sea ice coverage, illustrative of the important fact that climate change entails spatial contrasts. The decreasing ice coverage in the Arctic corresponds well with contemporaneous Arctic warming and exhibits particularly large decreases in the summers of 2007 and 2012, influenced by both preconditioning and atmospheric conditions. The increasing ice coverage in the Antarctic is not as readily explained, but spatial differences in the Antarctic trends suggest a possible connection with atmospheric circulation changes that have perhaps been influenced by the Antarctic ozone hole. The changes in the polar ice covers and the issues surrounding those changes have many commonalities with broader climate changes and their surrounding issues, allowing the sea ice changes to be viewed in some important ways as a microcosm of global climate change.

  18. The Opening of the Arctic-Atlantic Gateway: Tectonic, Oceanographic and Climatic Dynamics - an IODP Initiative

    Science.gov (United States)

    Geissler, Wolfram; Knies, Jochen

    2016-04-01

    The modern polar cryosphere reflects an extreme climate state with profound temperature gradients towards high-latitudes. It developed in association with stepwise Cenozoic cooling, beginning with ephemeral glaciations and the appearance of sea ice in the late middle Eocene. The polar ocean gateways played a pivotal role in changing the polar and global climate, along with declining greenhouse gas levels. The opening of the Drake Passage finalized the oceanographic isolation of Antarctica, some 40 Ma ago. The Arctic Ocean was an isolated basin until the early Miocene when rifting and subsequent sea-floor spreading started between Greenland and Svalbard, initiating the opening of the Fram Strait / Arctic-Atlantic Gateway (AAG). Although this gateway is known to be important in Earth's past and modern climate, little is known about its Cenozoic development. However, the opening history and AAG's consecutive widening and deepening must have had a strong impact on circulation and water mass exchange between the Arctic Ocean and the North Atlantic. To study the AAG's complete history, ocean drilling at two primary sites and one alternate site located between 73°N and 78°N in the Boreas Basin and along the East Greenland continental margin are proposed. These sites will provide unprecedented sedimentary records that will unveil (1) the history of shallow-water exchange between the Arctic Ocean and the North Atlantic, and (2) the development of the AAG to a deep-water connection and its influence on the global climate system. The specific overarching goals of our proposal are to study: (1) the influence of distinct tectonic events in the development of the AAG and the formation of deep water passage on the North Atlantic and Arctic paleoceanography, and (2) the role of the AAG in the climate transition from the Paleogene greenhouse to the Neogene icehouse for the long-term (~50 Ma) climate history of the northern North Atlantic. Getting a continuous record of the

  19. Climate change alters leaf anatomy, but has no effects on volatile emissions from Arctic plants.

    Science.gov (United States)

    Schollert, Michelle; Kivimäenpää, Minna; Valolahti, Hanna M; Rinnan, Riikka

    2015-10-01

    Biogenic volatile organic compound (BVOC) emissions are expected to change substantially because of the rapid advancement of climate change in the Arctic. BVOC emission changes can feed back both positively and negatively on climate warming. We investigated the effects of elevated temperature and shading on BVOC emissions from arctic plant species Empetrum hermaphroditum, Cassiope tetragona, Betula nana and Salix arctica. Measurements were performed in situ in long-term field experiments in subarctic and high Arctic using a dynamic enclosure system and collection of BVOCs into adsorbent cartridges analysed by gas chromatography-mass spectrometry. In order to assess whether the treatments had resulted in anatomical adaptations, we additionally examined leaf anatomy using light microscopy and scanning electron microscopy. Against expectations based on the known temperature and light-dependency of BVOC emissions, the emissions were barely affected by the treatments. In contrast, leaf anatomy of the studied plants was significantly altered in response to the treatments, and these responses appear to differ from species found at lower latitudes. We suggest that leaf anatomical acclimation may partially explain the lacking treatment effects on BVOC emissions at plant shoot-level. However, more studies are needed to unravel why BVOC emission responses in arctic plants differ from temperate species.

  20. Collaborative Research. Quantifying Climate Feedbacks of the Terrestrial Biosphere under Thawing Permafrost Conditions in the Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Qianlai [Purdue Univ., West Lafayette, IN (United States); Schlosser, Courtney [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Melillo, Jerry [Marine Biological Lab. (MBL), Woods Hole, MA (United States); Walter, Katey [Univ. of Alaska, Fairbanks, AK (United States)

    2015-09-15

    Our overall goal is to quantify the potential for threshold changes in natural emission rates of trace gases, particularly methane and carbon dioxide, from pan-arctic terrestrial systems under the spectrum of anthropogenically-forced climate warming, and the conditions under which these emissions provide a strong feedback mechanism to global climate warming. This goal is motivated under the premise that polar amplification of global climate warming will induce widespread thaw and degradation of the permafrost, and would thus cause substantial changes to the landscape of wetlands and lakes, especially thermokarst (thaw) lakes, across the Arctic. Through a suite of numerical experiments that encapsulate the fundamental processes governing methane emissions and carbon exchanges – as well as their coupling to the global climate system - we intend to test the following hypothesis in the proposed research: There exists a climate warming threshold beyond which permafrost degradation becomes widespread and stimulates large increases in methane emissions (via thermokarst lakes and poorly-drained wetland areas upon thawing permafrost along with microbial metabolic responses to higher temperatures) and increases in carbon dioxide emissions from well-drained areas. Besides changes in biogeochemistry, this threshold will also influence global energy dynamics through effects on surface albedo, evapotranspiration and water vapor. These changes would outweigh any increased uptake of carbon (e.g. from peatlands and higher plant photosynthesis) and would result in a strong, positive feedback to global climate warming.

  1. Boundary layer stability and Arctic climate change: a feedback study using EC-Earth

    NARCIS (Netherlands)

    Bintanja, R.; Linden, van der E.C.; Hazeleger, W.

    2012-01-01

    Amplified Arctic warming is one of the key features of climate change. It is evident in observations as well as in climate model simulations. Usually referred to as Arctic amplification, it is generally recognized that the surface albedo feedback governs the response. However, a number of feedback m

  2. Modeling of Arctic Climate: Fairbanks-Barrow Top of the World Summer School

    Science.gov (United States)

    Alexeev, V. A.; Walsh, J. E.; Sparrow, E. B.

    2009-04-01

    Arctic climate is the result of a complex interplay between the atmosphere, the ocean, sea ice and a terrestrial component in which freezing and thawing are critical to variations over a range of timescales. In view of the delicate balances between these components and their poorly documented sensitivities, it is not surprising that global climate models show the largest disagreement among themselves, and also the strongest greenhouse-induced changes, in the polar regions. Since changes in the Arctic may well have global implications, it is essential that Arctic climate simulations be enhanced in order to reduce the uncertainties in projections of climate change. Given the challenges and opportunities in Arctic modeling, the International Arctic Research Center's (IARC) 2008 summer school at the University of Alaska Fairbanks (UAF), was designed to bring the next generation of climate modelers to the Arctic. The two-week summer school brought together a group of 16 graduate students and young scientists, as well as specialists in Arctic climate and climate modeling, for two weeks, the first week in Fairbanks (May 27-31) and the second in Barrow (June 1-6). The young scientists gained a perspective on the key issues in Arctic climate from observational, diagnostic and modeling perspectives and received hands-on experience in the analysis of climate model output or in climate model experimentation at a level consistent with the students' expertise. The summer school consisted of background pedagogical lectures in the mornings, and mini-projects and informal discussions in the afternoons. The mini-projects have been performed in collaboration with lecturers, and utilized existing databases and available models. The second week was spent observing and experiencing Arctic research first-hand in Barrow, Alaska in coordination with the Barrow Arctic Sciences Consortium (BASC). The summer school and IARC are supported by the NSF, NOAA and JAMSTEC.

  3. Climate change and natural hazards in the Arctic

    Science.gov (United States)

    Eichelberger, J. C.; Eichelberger, L. P.

    2015-12-01

    Climate change is motivating much of the science research in the Arctic. Natural hazards, which have always been with us and can be influenced by climate, also pose a serious threat to sustainability of Arctic communities, the Native cultures they support, and the health and wellbeing of their residents. These are themes of the US Chairship of the Arctic Council. For example, repetitive floods, often associated with spring ice jams, are a particularly severe problem for river communities. People live near rivers because access to food, water and river transportation support an indigenous subsistence lifestyle. Some settlement sites for Indigenous Peoples were mandated by distant authorities without regard to natural hazards, in Alaska no less than in other countries. Thus bad policy of the past casts a long shadow into the future. Remote communities are subject to multiple challenges, including natural hazards, access to education, and limited job opportunities. These intersect to reproduce structural vulnerability and have over time created a need for substantial support from government. In the past 40 years, the themes of "sustainability" and "self reliance" have become prominent strategies for governance at both state and local levels. Communities now struggle to demonstrate their sustainability while grappling with natural hazards and chronic poverty. In the extreme, the shifting of responsibility to resource-poor communities can be called "structural violence". Accepting the status quo can mean living without sanitation and reliable water supply, leading to the high observed rates of disease not normally encountered in developed countries. Many of the efforts to address climate change and natural hazards are complementary: monitoring the environment; forecasting extreme events; and community-based participatory research and planning. Natural disaster response is complementary to the Arctic Council's Search and Rescue (SAR) initiative, differing in that those

  4. Holocene climate change in Arctic Canada and Greenland

    Science.gov (United States)

    Briner, Jason P.; McKay, Nicholas P.; Axford, Yarrow; Bennike, Ole; Bradley, Raymond S.; de Vernal, Anne; Fisher, David; Francus, Pierre; Fréchette, Bianca; Gajewski, Konrad; Jennings, Anne; Kaufman, Darrell S.; Miller, Gifford; Rouston, Cody; Wagner, Bernd

    2016-09-01

    This synthesis paper summarizes published proxy climate evidence showing the spatial and temporal pattern of climate change through the Holocene in Arctic Canada and Greenland. Our synthesis includes 47 records from a recently published database of highly resolved Holocene paleoclimate time series from the Arctic (Sundqvist et al., 2014). We analyze the temperature histories represented by the database and compare them with paleoclimate and environmental information from 54 additional published records, mostly from datasets that did not fit the selection criteria for the Arctic Holocene database. Combined, we review evidence from a variety of proxy archives including glaciers (ice cores and glacial geomorphology), lake sediments, peat sequences, and coastal and deep-marine sediments. The temperature-sensitive records indicate more consistent and earlier Holocene warmth in the north and east, and a more diffuse and later Holocene thermal maximum in the south and west. Principal components analysis reveals two dominant Holocene trends, one with early Holocene warmth followed by cooling in the middle Holocene, the other with a broader period of warmth in the middle Holocene followed by cooling in the late Holocene. The temperature decrease from the warmest to the coolest portions of the Holocene is 3.0 ± 1.0 °C on average (n = 11 sites). The Greenland Ice Sheet retracted to its minimum extent between 5 and 3 ka, consistent with many sites from around Greenland depicting a switch from warm to cool conditions around that time. The spatial pattern of temperature change through the Holocene was likely driven by the decrease in northern latitude summer insolation through the Holocene, the varied influence of waning ice sheets in the early Holocene, and the variable influx of Atlantic Water into the study region.

  5. Relating Regional Arctic Sea Ice and climate extremes over Europe

    Science.gov (United States)

    Ionita-Scholz, Monica; Grosfeld, Klaus; Lohmann, Gerrit; Scholz, Patrick

    2016-04-01

    The potential increase of temperature extremes under climate change is a major threat to society, as temperature extremes have a deep impact on environment, hydrology, agriculture, society and economy. Hence, the analysis of the mechanisms underlying their occurrence, including their relationships with the large-scale atmospheric circulation and sea ice concentration, is of major importance. At the same time, the decline in Arctic sea ice cover during the last 30 years has been widely documented and it is clear that this change is having profound impacts at regional as well as planetary scale. As such, this study aims to investigate the relation between the autumn regional sea ice concentration variability and cold winters in Europe, as identified by the numbers of cold nights (TN10p), cold days (TX10p), ice days (ID) and consecutive frost days (CFD). We analyze the relationship between Arctic sea ice variation in autumn (September-October-November) averaged over eight different Arctic regions (Barents/Kara Seas, Beaufort Sea, Chukchi/Bering Seas, Central Arctic, Greenland Sea, Labrador Sea/Baffin Bay, Laptev/East Siberian Seas and Northern Hemisphere) and variations in atmospheric circulation and climate extreme indices in the following winter season over Europe using composite map analysis. Based on the composite map analysis it is shown that the response of the winter extreme temperatures over Europe is highly correlated/connected to changes in Arctic sea ice variability. However, this signal is not symmetrical for the case of high and low sea ice years. Moreover, the response of temperatures extreme over Europe to sea ice variability over the different Arctic regions differs substantially. The regions which have the strongest impact on the extreme winter temperature over Europe are: Barents/Kara Seas, Beaufort Sea, Central Arctic and the Northern Hemisphere. For the years of high sea ice concentration in the Barents/Kara Seas there is a reduction in the number

  6. Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC)

    Science.gov (United States)

    Dethloff, Klaus; Rex, Markus; Shupe, Matthew

    2016-04-01

    The Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) is an international initiative under the International Arctic Science Committee (IASC) umbrella that aims to improve numerical model representations of sea ice, weather, and climate processes through coupled system observations and modeling activities that link the central Arctic atmosphere, sea ice, ocean, and the ecosystem. Observations of many critical parameters such as cloud properties, surface energy fluxes, atmospheric aerosols, small-scale sea-ice and oceanic processes, biological feedbacks with the sea-ice ice and ocean, and others have never been made in the central Arctic in all seasons, and certainly not in a coupled system fashion. The primary objective of MOSAiC is to develop a better understanding of these important coupled-system processes so they can be more accurately represented in regional- and global-scale weather- and climate models. Such enhancements will contribute to improved modeling of global climate and weather, and Arctic sea-ice predictive capabilities. The MOSAiC observations are an important opportunity to gather the high quality and comprehensive observations needed to improve numerical modeling of critical, scale-dependent processes impacting Arctic predictability given diminished sea ice coverage and increased model complexity. Model improvements are needed to understand the effects of a changing Arctic on mid-latitude weather and climate. MOSAiC is specifically designed to provide the multi-parameter, coordinated observations needed to improve sub-grid scale model parameterizations especially with respect to thinner ice conditions. To facilitate, evaluate, and develop the needed model improvements, MOSAiC will employ a hierarchy of modeling approaches ranging from process model studies, to regional climate model intercomparisons, to operational forecasts and assimilation of real-time observations. Model evaluations prior to the field program will

  7. Arctic dimension of global warming

    Directory of Open Access Journals (Sweden)

    G. V. Alekseev

    2014-01-01

    Full Text Available A brief assessment of the global warming in the Arctic climate system with the emphasis on sea ice is presented. The Arctic region is coupled to the global climate system by the atmosphere and ocean circulation that providesa major contribution to the Arctic energy budget. On this basis using of special indices it is shown that amplification of warming in the Arctic is associated with the increasing of meridional heat transport from the low latitudes.

  8. Future Climate Change Will Favour Non-Specialist Mammals in the (Sub)Arctics

    OpenAIRE

    Hof, Anouschka R.; Roland Jansson; Christer Nilsson

    2012-01-01

    Arctic and subarctic (i.e., [sub] arctic) ecosystems are predicted to be particularly susceptible to climate change. The area of tundra is expected to decrease and temperate climates will extend further north, affecting species inhabiting northern environments. Consequently, species at high latitudes should be especially susceptible to climate change, likely experiencing significant range contractions. Contrary to these expectations, our modelling of species distributions suggests that predic...

  9. Arctic cities and climate change: climate-induced changes in stability of Russian urban infrastructure built on permafrost

    Science.gov (United States)

    Shiklomanov, Nikolay; Streletskiy, Dmitry; Swales, Timothy

    2014-05-01

    Planned socio-economic development during the Soviet period promoted migration into the Arctic and work force consolidation in urbanized settlements to support mineral resources extraction and transportation industries. These policies have resulted in very high level of urbanization in the Soviet Arctic. Despite the mass migration from the northern regions during the 1990s following the collapse of the Soviet Union and the diminishing government support, the Russian Arctic population remains predominantly urban. In five Russian Administrative regions underlined by permafrost and bordering the Arctic Ocean 66 to 82% (depending on region) of the total population is living in Soviet-era urban communities. The political, economic and demographic changes in the Russian Arctic over the last 20 years are further complicated by climate change which is greatly amplified in the Arctic region. One of the most significant impacts of climate change on arctic urban landscapes is the warming and degradation of permafrost which negatively affects the structural integrity of infrastructure. The majority of structures in the Russian Arctic are built according to the passive principle, which promotes equilibrium between the permafrost thermal regime and infrastructure foundations. This presentation is focused on quantitative assessment of potential changes in stability of Russian urban infrastructure built on permafrost in response to ongoing and future climatic changes using permafrost - geotechnical model forced by GCM-projected climate. To address the uncertainties in GCM projections we have utilized results from 6 models participated in most recent IPCC model inter-comparison project. The analysis was conducted for entire extent of Russian permafrost-affected area and on several representative urban communities. Our results demonstrate that significant observed reduction in urban infrastructure stability throughout the Russian Arctic can be attributed to climatic changes and that

  10. Wave Climate and Wave Mixing in the Marginal Ice Zones of Arctic Seas, Observations and Modelling

    Science.gov (United States)

    2014-09-30

    from the ocean /sea is ambiguous. If not accounted for ice, however, statistics and therefore climatology in the Arctic Seas will be biased by surface...the Arctic wave climate continued by means of coupled wave, ice and general circulation modelling, and the study of wave-ice interaction in the...the open ocean was performed. This allowed preliminary analysis of trends for wave heights over areas of the Arctic Ocean free of ice over the

  11. Arctic Vegetation under Climate Change – Biogenic Volatile Organic Compound Emissions and Leaf Anatomy

    DEFF Research Database (Denmark)

    Schollert, Michelle

    Biogenic volatile organic compounds (BVOCs) emitted from terrestrial vegetation are highly reactive non-methane hydrocarbons which participate in oxidative reactions in the atmosphere prolonging the lifetime of methane and contribute to the formation of secondary organic aerosols. The BVOC...... measurements in this thesis were performed using a dynamic enclosure system and collection of BVOCs into adsorbent cartridges analyzed by gas chromatography-mass spectrometry following thermal desorption. Also modifications in leaf anatomy in response to the studied effects of climate change were assessed...... by the use of light microscopy and scanning electron microscopy. This thesis reports the first estimates of high arctic BVOC emissions, which suggest that arctic environments can be a considerable source of BVOCs to the atmosphere. The BVOC emissions differed qualitatively and quantitatively for the studied...

  12. Patterns and processes influencing helminth parasites of Arctic coastal communities during climate change.

    Science.gov (United States)

    Galaktionov, K V

    2017-03-22

    This review analyses the scarce available data on biodiversity and transmission of helminths in Arctic coastal ecosystems and the potential impact of climate changes on them. The focus is on the helminths of seabirds, dominant parasites in coastal ecosystems. Their fauna in the Arctic is depauperate because of the lack of suitable intermediate hosts and unfavourable conditions for species with free-living larvae. An increasing proportion of crustaceans in the diet of Arctic seabirds would result in a higher infection intensity of cestodes and acanthocephalans, and may also promote the infection of seabirds with non-specific helminths. In this way, the latter may find favourable conditions for colonization of new hosts. Climate changes may alter the composition of the helminth fauna, their infection levels in hosts and ways of transmission in coastal communities. Immigration of boreal invertebrates and fish into Arctic seas may allow the circulation of helminths using them as intermediate hosts. Changing migratory routes of animals would alter the distribution of their parasites, facilitating, in particular, their trans-Arctic transfer. Prolongation of the seasonal 'transmission window' may increase the parasitic load on host populations. Changes in Arctic marine food webs would have an overriding influence on the helminths' circulation. This process may be influenced by the predicted decreased of salinity in Arctic seas, increased storm activity, coastal erosion, ocean acidification, decline of Arctic ice, etc. Greater parasitological research efforts are needed to assess the influence of factors related to Arctic climate change on the transmission of helminths.

  13. Climate Change and China as a Global Emerging Regulatory Sea Power in the Arctic Ocean

    DEFF Research Database (Denmark)

    Cassotta, Sandra; Hossain, Kamrul; Ren, Jingzheng

    2015-01-01

    on the Law of the Sea (UNCLOS) and the Arctic Council (AC) are taken into consideration under climate change effects, to assess how global legal frameworks and institutions can deal with China’s strategy in the Arctic Ocean. China’s is moving away from its role as “humble power” to one of “informal...

  14. Climate change in the North American Arctic: A one health perspective

    Science.gov (United States)

    Climate change is expected to increase the prevalence of acute and chronic diseases among human and animal populations within the Arctic and sub-Arctic latitudes of North America. Warmer temperatures are expected to increase disease risks from food-borne pathogens, water-borne diseases, and vector-...

  15. Future climate change will favour non-specialist mammals in the (sub)arctics.

    Science.gov (United States)

    Hof, Anouschka R; Jansson, Roland; Nilsson, Christer

    2012-01-01

    Arctic and subarctic (i.e., [sub]arctic) ecosystems are predicted to be particularly susceptible to climate change. The area of tundra is expected to decrease and temperate climates will extend further north, affecting species inhabiting northern environments. Consequently, species at high latitudes should be especially susceptible to climate change, likely experiencing significant range contractions. Contrary to these expectations, our modelling of species distributions suggests that predicted climate change up to 2080 will favour most mammals presently inhabiting (sub)arctic Europe. Assuming full dispersal ability, most species will benefit from climate change, except for a few cold-climate specialists. However, most resident species will contract their ranges if they are not able to track their climatic niches, but no species is predicted to go extinct. If climate would change far beyond current predictions, however, species might disappear. The reason for the relative stability of mammalian presence might be that arctic regions have experienced large climatic shifts in the past, filtering out sensitive and range-restricted taxa. We also provide evidence that for most (sub)arctic mammals it is not climate change per se that will threaten them, but possible constraints on their dispersal ability and changes in community composition. Such impacts of future changes in species communities should receive more attention in literature.

  16. Marine Mammals and Climate Change in the Pacific Arctic: Impacts & Resilience

    Science.gov (United States)

    Moore, S. E.

    2014-12-01

    Extreme reductions in Arctic sea ice extent and thickness have become a hallmark of climate change, but impacts to the marine ecosystem are poorly understood. As top predators, marine mammals must adapt to biological responses to physical forcing and thereby become sentinels to ecosystem variability and reorganization. Recent sea ice retreats have influenced the ecology of marine mammals in the Pacific Arctic sector. Walruses now often haul out by the thousands along the NW Alaska coast in late summer, and reports of harbor porpoise, humpback, fin and minke whales in the Chukchi Sea demonstrate that these temperate species routinely occur there. In 2010, satellite tagged bowhead whales from Atlantic and Pacific populations met in the Northwest Passage, an overlap thought precluded by sea ice since the Holocene. To forage effectively, baleen whales must target dense patches of zooplankton and small fishes. In the Pacific Arctic, bowhead and gray whales appear to be responding to enhanced prey availability delivered both by new production and advection pathways. Two programs, the Distributed Biological Observatory (DBO) and the Synthesis of Arctic Research (SOAR), include tracking of marine mammal and prey species' responses to ecosystem shifts associated with sea ice loss. Both programs provide an integrated-ecosystem baseline in support of the development of a web-based Marine Mammal Health Map, envisioned as a component of the U.S. Integrated Ocean Observing System (IOOS). An overarching goal is to identify ecological patterns for marine mammals in the 'new' Arctic, as a foundation for integrative research, local response and adaptive management.

  17. US CLIVAR Working Group: Arctic Change and Possible Influence on Mid-latitude Climate and Weather

    Science.gov (United States)

    Cohen, J. L.; Zhang, X.

    2015-12-01

    The Arctic has warmed more than twice as fast as the global average, a phenomenon known as Arctic amplification (AA). These profound changes to the Arctic system have coincided with a period of ostensibly more frequent events of extreme weather across the Northern Hemisphere mid-latitudes, including extreme heat and rainfall events and recent severe winters. The possible link between Arctic change and mid-latitude weather has spurred a rush of new observational and modeling studies. These studies have argued that heavy precipitation events and heat waves are at least partially attributable to Arctic warming. A growing number of recent studies even argue that recent extreme winter weather is related to AA. In part due to the high impact of extreme weather on our society, some of these studies linking AA to the increased frequency of extreme weather have garnered public and media attention. At the same time, uncertainties from the large intrinsic variability of the system, the short observational record due to the recentness of AA and the shortcomings of global climate models have also resulted in much skepticism in any argued links between AA and severe weather. This in turn has resulted in a number of workshops trying to frame the problem and laying the groundwork to improve our understanding of Arctic-mid-latitude linkages and accurate attribution of extreme weather events. Although these workshops identified existing problems and difficulties, and provided broad recommendations, they did not synthesize the diversified research results to identify where community consensus and gaps exist. Therefore we have assembled many of the leading scientists researching Arctic-mid-latitude linkages as part of a US CLIVAR working group. Through the three-year efforts of this working group, we will use the outcome of the previous workshops and newly planned activities to guide the synthesis efforts, coordinate on-going research to fill out key gaps, and provide specific

  18. Wave climate in the Arctic 1992-2014: seasonality and trends

    Science.gov (United States)

    Stopa, Justin E.; Ardhuin, Fabrice; Girard-Ardhuin, Fanny

    2016-07-01

    Over the past decade, the diminishing Arctic sea ice has impacted the wave field, which depends on the ice-free ocean and wind. This study characterizes the wave climate in the Arctic spanning 1992-2014 from a merged altimeter data set and a wave hindcast that uses CFSR winds and ice concentrations from satellites as input. The model performs well, verified by the altimeters, and is relatively consistent for climate studies. The wave seasonality and extremes are linked to the ice coverage, wind strength, and wind direction, creating distinct features in the wind seas and swells. The altimeters and model show that the reduction of sea ice coverage causes increasing wave heights instead of the wind. However, trends are convoluted by interannual climate oscillations like the North Atlantic Oscillation (NAO) and Pacific Decadal Oscillation. In the Nordic Greenland Sea the NAO influences the decreasing wind speeds and wave heights. Swells are becoming more prevalent and wind-sea steepness is declining. The satellite data show the sea ice minimum occurs later in fall when the wind speeds increase. This creates more favorable conditions for wave development. Therefore we expect the ice freeze-up in fall to be the most critical season in the Arctic and small changes in ice cover, wind speeds, and wave heights can have large impacts to the evolution of the sea ice throughout the year. It is inconclusive how important wave-ice processes are within the climate system, but selected events suggest the importance of waves within the marginal ice zone.

  19. Boundary layer stability and Arctic climate change: a feedback study using EC-Earth

    Science.gov (United States)

    Bintanja, R.; van der Linden, E. C.; Hazeleger, W.

    2012-12-01

    Amplified Arctic warming is one of the key features of climate change. It is evident in observations as well as in climate model simulations. Usually referred to as Arctic amplification, it is generally recognized that the surface albedo feedback governs the response. However, a number of feedback mechanisms play a role in AA, of which those related to the prevalent near-surface inversion have received relatively little attention. Here we investigate the role of the near-surface thermal inversion, which is caused by radiative surface cooling in autumn and winter, on Arctic warming. We employ idealized climate change experiments using the climate model EC-Earth together with ERA-Interim reanalysis data to show that boundary-layer mixing governs the efficiency by which the surface warming signal is `diluted' to higher levels. Reduced vertical mixing, as in the stably stratified inversion layer in Arctic winter, thus amplifies surface warming. Modelling results suggest that both shortwave—through the (seasonal) interaction with the sea ice feedback—and longwave feedbacks are affected by boundary-layer mixing, both in the Arctic and globally, with the effect on the shortwave feedback dominating. The amplifying effect will decrease, however, with climate warming because the surface inversion becomes progressively weaker. We estimate that the reduced Arctic inversion has slowed down global warming by about 5% over the past 2 decades, and we anticipate that it will continue to do so with ongoing Arctic warming.

  20. Gender specific reproductive strategies of an arctic key species (Boreogadus saida) and implications of climate change.

    Science.gov (United States)

    Nahrgang, Jasmine; Varpe, Oystein; Korshunova, Ekaterina; Murzina, Svetlana; Hallanger, Ingeborg G; Vieweg, Ireen; Berge, Jørgen

    2014-01-01

    The Arctic climate is changing at an unprecedented rate. What consequences this may have on the Arctic marine ecosystem depends to a large degree on how its species will respond both directly to elevated temperatures and more indirectly through ecological interactions. But despite an alarming recent warming of the Arctic with accompanying sea ice loss, reports evaluating ecological impacts of climate change in the Arctic remain sparse. Here, based upon a large-scale field study, we present basic new knowledge regarding the life history traits for one of the most important species in the entire Arctic, the polar cod (Boreogadus saida). Furthermore, by comparing regions of contrasting climatic influence (domains), we present evidence as to how its growth and reproductive success is impaired in the warmer of the two domains. As the future Arctic is predicted to resemble today's Atlantic domains, we forecast changes in growth and life history characteristics of polar cod that will lead to alteration of its role as an Arctic keystone species. This will in turn affect community dynamics and energy transfer in the entire Arctic food chain.

  1. Gender specific reproductive strategies of an arctic key species (Boreogadus saida and implications of climate change.

    Directory of Open Access Journals (Sweden)

    Jasmine Nahrgang

    Full Text Available The Arctic climate is changing at an unprecedented rate. What consequences this may have on the Arctic marine ecosystem depends to a large degree on how its species will respond both directly to elevated temperatures and more indirectly through ecological interactions. But despite an alarming recent warming of the Arctic with accompanying sea ice loss, reports evaluating ecological impacts of climate change in the Arctic remain sparse. Here, based upon a large-scale field study, we present basic new knowledge regarding the life history traits for one of the most important species in the entire Arctic, the polar cod (Boreogadus saida. Furthermore, by comparing regions of contrasting climatic influence (domains, we present evidence as to how its growth and reproductive success is impaired in the warmer of the two domains. As the future Arctic is predicted to resemble today's Atlantic domains, we forecast changes in growth and life history characteristics of polar cod that will lead to alteration of its role as an Arctic keystone species. This will in turn affect community dynamics and energy transfer in the entire Arctic food chain.

  2. Arctic marine climate of the early nineteenth century

    Directory of Open Access Journals (Sweden)

    P. Brohan

    2010-05-01

    Full Text Available The climate of the early nineteenth century is likely to have been significantly cooler than that of today, as it was a period of low solar activity (the Dalton minimum and followed a series of large volcanic eruptions. Proxy reconstructions of the temperature of the period do not agree well on the size of the temperature change, so other observational records from the period are particularly valuable. Weather observations have been extracted from the reports of the noted whaling captain William Scoresby Jr., and from the records of a series of Royal Navy expeditions to the Arctic, preserved in the UK National Archives. They demonstrate that marine climate in 1810–1825 was marked by consistently cold summers, with abundant sea-ice. But although the period was significantly colder than the modern average, there was considerable variability: in the Greenland Sea the summers following the Tambora eruption (1816 and 1817 were noticeably warmer, and had less sea-ice coverage, than the years immediately preceding them; and the sea-ice coverage in Lancaster Sound in 1819 and 1820 was low even by modern standards.

  3. Biased thermohaline exchanges with the Arctic across the Iceland-Faroe Ridge in ocean climate models

    Science.gov (United States)

    Olsen, S. M.; Hansen, B.; Østerhus, S.; Quadfasel, D.; Valdimarsson, H.

    2016-04-01

    The northern limb of the Atlantic thermohaline circulation and its transport of heat and salt towards the Arctic strongly modulate the climate of the Northern Hemisphere. The presence of warm surface waters prevents ice formation in parts of the Arctic Mediterranean, and ocean heat is directly available for sea-ice melt, while salt transport may be critical for the stability of the exchanges. Through these mechanisms, ocean heat and salt transports play a disproportionally strong role in the climate system, and realistic simulation is a requisite for reliable climate projections. Across the Greenland-Scotland Ridge (GSR) this occurs in three well-defined branches where anomalies in the warm and saline Atlantic inflow across the shallow Iceland-Faroe Ridge (IFR) have been shown to be particularly difficult to simulate in global ocean models. This branch (IF-inflow) carries about 40 % of the total ocean heat transport into the Arctic Mediterranean and is well constrained by observation during the last 2 decades but associated with significant inter-annual fluctuations. The inconsistency between model results and observational data is here explained by the inability of coarse-resolution models to simulate the overflow across the IFR (IF-overflow), which feeds back onto the simulated IF-inflow. In effect, this is reduced in the model to reflect only the net exchange across the IFR. Observational evidence is presented for a substantial and persistent IF-overflow and mechanisms that qualitatively control its intensity. Through this, we explain the main discrepancies between observed and simulated exchange. Our findings rebuild confidence in modelled net exchange across the IFR, but reveal that compensation of model deficiencies here through other exchange branches is not effective. This implies that simulated ocean heat transport to the Arctic is biased low by more than 10 % and associated with a reduced level of variability, while the quality of the simulated salt

  4. Biased thermohaline exchanges with the arctic across the Iceland-Faroe Ridge in ocean climate models

    Directory of Open Access Journals (Sweden)

    S. M. Olsen

    2015-07-01

    Full Text Available The northern limb of the Atlantic thermohaline circulation and its transport of heat and salt towards the Arctic strongly modulates the climate of the Northern Hemisphere. Presence of warm surface waters prevents ice formation in parts of the Arctic Mediterranean and ocean heat is in critical regions directly available for sea-ice melt, while salt transport may be critical for the stability of the exchanges. Hereby, ocean heat and salt transports play a disproportionally strong role in the climate system and realistic simulation is a requisite for reliable climate projections. Across the Greenland-Scotland Ridge (GSR this occurs in three well defined branches where anomalies in the warm and saline Atlantic inflow across the shallow Iceland-Faroe Ridge (IFR have shown particularly difficult to simulate in global ocean models. This branch (IF-inflow carries about 40 % of the total ocean heat transport into the Arctic Mediterranean and is well constrained by observation during the last two decades but is associated with significant inter-annual fluctuations. The inconsistency between model results and observational data is here explained by the inability of coarse resolution models to simulate the overflow across the IFR (IF-overflow, which feeds back on the simulated IF-inflow. In effect, this is reduced in the model to reflect only the net exchange across the IFR. Observational evidence is presented for a substantial and persistent IF-overflow and mechanisms that qualitatively control its intensity. Through this, we explain the main discrepancies between observed and simulated exchange. Our findings rebuild confidence in modeled net exchange across the IFR, but reveal that compensation of model deficiencies here through other exchange branches is not effective. This implies that simulated ocean heat transport to the Arctic is biased low by more than 10 % and associated with a reduced level of variability while the quality of the simulated salt

  5. The effect on Arctic climate of atmospheric meridional energy-transport changes studied based on the CESM climate model

    Science.gov (United States)

    Grand Graversen, Rune

    2016-04-01

    The Arctic amplification of global warming and the pronounced Arctic sea-ice retreat constitute some of the most alarming signs of global climate change. These Arctic changes are likely a consequence of a combination of several processes, for instance enhanced uptake of solar radiation in the Arctic due to a lowering of the planetary albedo, and increase in the local Arctic greenhouse effect due to enhanced moister flux from lower latitudes. Many of the proposed processes appear to be dependent on each other, for instance an increase in water-vapour advection to the Arctic enhances the greenhouse effect in the Arctic and the longwave radiation to the surface which melts the sea ice and causes an increase in absorption of solar radiation. The effects of albedo changes have been investigated in earlier studies based on model experiments designed to examine these effects specifically. Here we instead focus on the effects of meridional transport changes into the Arctic, both of water vapour and dry-static energy. Hence we here present results of model experiments with the CESM climate model designed specifically to extract the effects of the changes of the two transport components.

  6. Impacts of Future Climate Change on Aerosol Transport to the Arctic

    Science.gov (United States)

    Flanner, M.; Jiao, C.

    2015-12-01

    Arctic climate is sensitive to small concentrations of light-absorbing aerosols like black carbon, and hence the impacts of global climate change on aerosol transport to the Arctic are of interest. Here, we explore how climate warming under the RCP 8.5 scenario would impact Arctic aerosol distributions via changes in atmospheric transport and removal processes. We modify the bulk aerosol module in the Community Atmosphere Model to track distributions and fluxes of 200 black carbon-like tracers emitted from different locations, and we conduct idealized experiments with and without active aerosol deposition. Changing wind patterns, operating in isolation, cause the Arctic burdens of tracers emitted from East Asia and West Europe during winter to increase about 20-30% by the end of the century, while decreasing the Arctic burdens of North American emissions by 20-40%. These changes are caused by an altered winter polar dome structure that results from Arctic amplification and inhomogeneous sea-ice loss and surface warming, both of which are enhanced in the Chukchi Sea region. The resulting geostrophic wind favors Arctic transport of East Asian emissions while inhibiting poleward transport of North American emissions. When active deposition is also considered, however, Arctic burdens of emissions from northern mid-latitudes show near-universal decline. This is a consequence of increased precipitation and wet removal, particularly within the Arctic, leading to decreased Arctic residence time. Simulations with present-day emissions of black carbon indicate a 17% reduction in the Arctic annual-mean burden by the end of the 21st century, due to warming-induced transport and deposition changes.

  7. Influence of climate change on the Arctic Contamination Potential

    Science.gov (United States)

    Hansen, Kaj M.; Christensen, Jesper H.; Brandt, Jørgen

    2014-05-01

    Using the Danish Eulerian Hemispheric Model (DEHM) we have calculated the Arctic Contamination Potential (ACP). ACP is defined as the sum of masses in the arctic surface compartments (soil, vegetation, snow and water) at the end of a ten year simulated period normalised either with the total mass within the model domain of with the total amount emitted into the atmosphere during the ten year simulation. In this study we use the emission normalized ACP termed eACP. We have calculated the eACP for the physical-chemical phase space spanned by compounds with log Koa between 3 and 12 and log Kaw between -4 and 3 and for each point in this phase space grid we have included a perfectly persistent compound in the model. DEHM is a 3-D atmospheric chemistry-transport model modelling the atmospheric transport of four chemical groups: a group with SOx-NOx-VOC-ozone chemistry, a group with primary particulates group, a mercury chemistry group, and finally a group with Persistent Organic Pollutants with 2-d surface compartments (soil, vegetation, ocean water and a dynamic temporal snow cover) with inter-compartmental mass exchange process parameterizations. The model domain covers the Northern Hemisphere and thus includes all important source areas for the Arctic. The spatial horizontal resolution of the model system in this work is 150km x 150km and the model includes 20 vertical levels up to approximately 15km above the surface. The model system was run with meteorology obtain from ECHAM5/MPI-OM (SRES A1B scenario) for two decades: 1990-1999 and 2090-2099. Highest potential (12%) for reaching the Arctic surface compartments for the 1990s is seen for compounds with low log Koa and low log Kaw values. These are relative water soluble compounds referred to as "swimmers". For the 2090s, the overall pattern of the ACP phase space is similar to the pattern for the 1990s. ACP is generally larger for the 2090s than for the 1990s, with a maximum of 15%.

  8. Climate change effects on human health in a gender perspective: some trends in Arctic research

    Directory of Open Access Journals (Sweden)

    Kukarenko Natalia

    2011-09-01

    Full Text Available Background: Climate change and environmental pollution have become pressing concerns for the peoples in the Arctic region. Some researchers link climate change, transformations of living conditions and human health. A number of studies have also provided data on differentiating effects of climate change on women's and men's well-being and health. Objective: To show how the issues of climate and environment change, human health and gender are addressed in current research in the Arctic. The main purpose of this article is not to give a full review but to draw attention to the gaps in knowledge and challenges in the Arctic research trends on climate change, human health and gender. Methods: A broad literature search was undertaken using a variety of sources from natural, medical, social science and humanities. The focus was on the keywords. Results: Despite the evidence provided by many researchers on differentiating effects of climate change on well-being and health of women and men, gender perspective remains of marginal interest in climate change, environmental and health studies. At the same time, social sciences and humanities, and gender studies in particular, show little interest towards climate change impacts on human health in the Arctic. As a result, we still observe the division of labour between disciplines, the disciplinary-bound pictures of human development in the Arctic and terminology confusion. Conclusion: Efforts to bring in a gender perspective in the Arctic research will be successful only when different disciplines would work together. Multidisciplinary research is a way to challenge academic/disciplinary homogeneity and their boundaries, to take advantage of the diversity of approaches and methods in production of new integrated knowledge. Cooperation and dialogue across disciplines will help to develop adequate indicators for monitoring human health and elaborating efficient policies and strategies to the benefit of both

  9. Arctic climate changes in the 21st century: Ensemble model estimates accounting for realism in present-day climate simulation

    Science.gov (United States)

    Eliseev, A. V.; Semenov, V. A.

    2016-11-01

    In the course of forecasting future climate changes in the Arctic Region based on calculations and an ensemble of the state-of-the-art global climate models, the results depend on the method of construction the statistics from the models.

  10. Rapid Arctic Changes due to Infrastructure and Climate (RATIC) in the Russian North

    Science.gov (United States)

    Walker, D. A.; Kofinas, G.; Raynolds, M. K.; Kanevskiy, M. Z.; Shur, Y.; Ambrosius, K.; Matyshak, G. V.; Romanovsky, V. E.; Kumpula, T.; Forbes, B. C.; Khukmotov, A.; Leibman, M. O.; Khitun, O.; Lemay, M.; Allard, M.; Lamoureux, S. F.; Bell, T.; Forbes, D. L.; Vincent, W. F.; Kuznetsova, E.; Streletskiy, D. A.; Shiklomanov, N. I.; Fondahl, G.; Petrov, A.; Roy, L. P.; Schweitzer, P.; Buchhorn, M.

    2015-12-01

    The Rapid Arctic Transitions due to Infrastructure and Climate (RATIC) initiative is a forum developed by the International Arctic Science Committee (IASC) Terrestrial, Cryosphere, and Social & Human working groups for developing and sharing new ideas and methods to facilitate the best practices for assessing, responding to, and adaptively managing the cumulative effects of Arctic infrastructure and climate change. An IASC white paper summarizes the activities of two RATIC workshops at the Arctic Change 2014 Conference in Ottawa, Canada and the 2015 Third International Conference on Arctic Research Planning (ICARP III) meeting in Toyama, Japan (Walker & Pierce, ed. 2015). Here we present an overview of the recommendations from several key papers and posters presented at these conferences with a focus on oil and gas infrastructure in the Russian north and comparison with oil development infrastructure in Alaska. These analyses include: (1) the effects of gas- and oilfield activities on the landscapes and the Nenets indigenous reindeer herders of the Yamal Peninsula, Russia; (2) a study of urban infrastructure in the vicinity of Norilsk, Russia, (3) an analysis of the effects of pipeline-related soil warming on trace-gas fluxes in the vicinity of Nadym, Russia, (4) two Canadian initiatives that address multiple aspects of Arctic infrastructure called Arctic Development and Adaptation to Permafrost in Transition (ADAPT) and the ArcticNet Integrated Regional Impact Studies (IRIS), and (5) the effects of oilfield infrastructure on landscapes and permafrost in the Prudhoe Bay region, Alaska.

  11. Biodiversity of Arctic marine ecosystems and responses to climate change

    DEFF Research Database (Denmark)

    Michel, C.; Bluhm, B.; Gallucci, V.

    2012-01-01

    The Arctic Ocean is undergoing major changes in many of its fundamental physical constituents, from a shift from multi- to first-year ice, shorter ice-covered periods, increasing freshwater runoff and surface stratification, to warming and alteration in the distribution of water masses...... that structure ecosystem biodiversity in the Arctic Ocean. We also discuss climateassociated effects on the biodiversity of Arctic marine ecosystems and discuss implications for the functioning of Arctic marine food webs. Based on the complexity and regional character of Arctic ecosystem reponses....... These changes have important impacts on the chemical and biological processes that are at the root of marine food webs, influencing their structure, function and biodiversity. Here we summarise current knowledge on the biodiversity of Arctic marine ecosystems and provide an overview of fundamental factors...

  12. Habitat-specific effects of climate change on a low-mobility Arctic spider species

    DEFF Research Database (Denmark)

    Bowden, Joseph James; Hansen, Rikke Reisner; Olsen, Kent;

    2015-01-01

    habitats. Such differences between habitats may influence the effects of climate changes on animals and this could be especially true in low-mobility species. Suitable model systems to test this idea, however, are rare. We examined how proxies of reproductive success (body size, juvenile/female ratios......Abstract Terrestrial ecosystems are heterogeneous habitat mosaics of varying vegetation types that are differentially affected by climate change. Arctic plant communities, for example, are changing faster in moist habitats than in dry habitats and abiotic changes like snowmelt vary locally among......) and sex ratios have changed in low-mobility crab spiders collected systematically over a 17-year period (1996–2012) from two distinct habitats (mesic and arid dwarf shrub heath) at Zackenberg in northeast Greenland. We identified all adults in the collection to confirm that they represented just one...

  13. Climate Change in the North American Arctic: A One Health Perspective.

    Science.gov (United States)

    Dudley, Joseph P; Hoberg, Eric P; Jenkins, Emily J; Parkinson, Alan J

    2015-12-01

    Climate change is expected to increase the prevalence of acute and chronic diseases among human and animal populations within the Arctic and subarctic latitudes of North America. Warmer temperatures are expected to increase disease risks from food-borne pathogens, water-borne diseases, and vector-borne zoonoses in human and animal populations of Arctic landscapes. Existing high levels of mercury and persistent organic pollutant chemicals circulating within terrestrial and aquatic ecosystems in Arctic latitudes are a major concern for the reproductive health of humans and other mammals, and climate warming will accelerate the mobilization and biological amplification of toxic environmental contaminants. The adverse health impacts of Arctic warming will be especially important for wildlife populations and indigenous peoples dependent upon subsistence food resources from wild plants and animals. Additional research is needed to identify and monitor changes in the prevalence of zoonotic pathogens in humans, domestic dogs, and wildlife species of critical subsistence, cultural, and economic importance to Arctic peoples. The long-term effects of climate warming in the Arctic cannot be adequately predicted or mitigated without a comprehensive understanding of the interactive and synergistic effects between environmental contaminants and pathogens in the health of wildlife and human communities in Arctic ecosystems. The complexity and magnitude of the documented impacts of climate change on Arctic ecosystems, and the intimacy of connections between their human and wildlife communities, makes this region an appropriate area for development of One Health approaches to identify and mitigate the effects of climate warming at the community, ecosystem, and landscape scales.

  14. Peeking Under the Ice… Literally: Records of Arctic Climate Change from Radiocarbon Dating Moss Emerging from Beneath Retreating Glaciers

    Science.gov (United States)

    Briner, J. P.; Schweinsberg, A.; Miller, G. H.; Lifton, N. A.; Beel, C. R.; Bennike, O.

    2014-12-01

    Dramatic changes are taking place throughout the Arctic. Many glaciers have already melted away completely, and most others are well on their way as rising snowline elevations promise continued glacier retreat. Emerging from beneath retreating glacier margins is a landscape rich in information about past climate and glacier changes. Within newly exposed bedrock is an inventory of cosmogenic nuclides that archive past ice cover timing and duration. Lake basins re-appearing due to retreating ice preserve sediment archives that tell of cooling climate and advancing ice. And ancient surfaces vegetated with tundra communities that have long been entombed beneath frozen-bedded ice caps are now being revealed for the first time in millennia. This presentation will focus on the climate and glacier record derived from radiocarbon dating of in situ moss recently exhumed from retreating local ice cap margins on western Greenland. Dozens of radiocarbon ages from moss group into several distinct modes, which are interpreted as discrete times of persistent summer cooling and resultant glacier expansion. The data reveal a pattern of glacier expansion beginning ~5000 years ago, followed by periods of glacier growth around 3500 and 1500 years ago. Because these times of glacier expansion are recorded at many sites in western Greenland and elsewhere in the Arctic, they are interpreted as times of step-wise summer cooling events during the Holocene. These non-linear climate changes may be a result of feedbacks that amplify linear insolation forcing of Holocene climate. In addition to these insights into the Arctic climate system, the antiquity of many radiocarbon ages of ice-killed moss indicate that many arctic surfaces are being re-exposed for the first time in millennia due to retreating ice, emphasizing the unprecedented nature of current summer warming.

  15. Remote sensing of aerosols in the Arctic for an evaluation of global climate model simulations.

    Science.gov (United States)

    Glantz, Paul; Bourassa, Adam; Herber, Andreas; Iversen, Trond; Karlsson, Johannes; Kirkevåg, Alf; Maturilli, Marion; Seland, Øyvind; Stebel, Kerstin; Struthers, Hamish; Tesche, Matthias; Thomason, Larry

    2014-07-16

    In this study Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua retrievals of aerosol optical thickness (AOT) at 555 nm are compared to Sun photometer measurements from Svalbard for a period of 9 years. For the 642 daily coincident measurements that were obtained, MODIS AOT generally varies within the predicted uncertainty of the retrieval over ocean (ΔAOT = ±0.03 ± 0.05 · AOT). The results from the remote sensing have been used to examine the accuracy in estimates of aerosol optical properties in the Arctic, generated by global climate models and from in situ measurements at the Zeppelin station, Svalbard. AOT simulated with the Norwegian Earth System Model/Community Atmosphere Model version 4 Oslo global climate model does not reproduce the observed seasonal variability of the Arctic aerosol. The model overestimates clear-sky AOT by nearly a factor of 2 for the background summer season, while tending to underestimate the values in the spring season. Furthermore, large differences in all-sky AOT of up to 1 order of magnitude are found for the Coupled Model Intercomparison Project phase 5 model ensemble for the spring and summer seasons. Large differences between satellite/ground-based remote sensing of AOT and AOT estimated from dry and humidified scattering coefficients are found for the subarctic marine boundary layer in summer.

  16. Arctic-HYCOS: a Large Sample observing system for estimating freshwater fluxes in the drainage basin of the Arctic Ocean

    Science.gov (United States)

    Pietroniro, Al; Korhonen, Johanna; Looser, Ulrich; Hardardóttir, Jórunn; Johnsrud, Morten; Vuglinsky, Valery; Gustafsson, David; Lins, Harry F.; Conaway, Jeffrey S.; Lammers, Richard; Stewart, Bruce; Abrate, Tommaso; Pilon, Paul; Sighomnou, Daniel; Arheimer, Berit

    2015-04-01

    The Arctic region is an important regulating component of the global climate system, and is also experiencing a considerable change during recent decades. More than 10% of world's river-runoff flows to the Arctic Ocean and there is evidence of changes in its fresh-water balance. However, about 30% of the Arctic basin is still ungauged, with differing monitoring practices and data availability from the countries in the region. A consistent system for monitoring and sharing of hydrological information throughout the Arctic region is thus of highest interest for further studies and monitoring of the freshwater flux to the Arctic Ocean. The purpose of the Arctic-HYCOS project is to allow for collection and sharing of hydrological data. Preliminary 616 stations were identified with long-term daily discharge data available, and around 250 of these already provide online available data in near real time. This large sample will be used in the following scientific analysis: 1) to evaluate freshwater flux to the Arctic Ocean and Seas, 2) to monitor changes and enhance understanding of the hydrological regime and 3) to estimate flows in ungauged regions and develop models for enhanced hydrological prediction in the Arctic region. The project is intended as a component of the WMO (World Meteorological Organization) WHYCOS (World Hydrological Cycle Observing System) initiative, covering the area of the expansive transnational Arctic basin with participation from Canada, Denmark, Finland, Iceland, Norway, Russian Federation, Sweden and United States of America. The overall objective is to regularly collect, manage and share high quality data from a defined basic network of hydrological stations in the Arctic basin. The project focus on collecting data on discharge and possibly sediment transport and temperature. Data should be provisional in near-real time if available, whereas time-series of historical data should be provided once quality assurance has been completed. The

  17. Arctic Climate Change: A Tale of Two Cod Species

    Science.gov (United States)

    Arctic cod play an important role in the Arctic trophic hierarchy as the consumer of primary productivity and a food source for many marine fish and mammals. Shifts in their distribution and abundance could have cascading affects in the marine environment. This paper investigates...

  18. Model Projections of East Asian Summer Climate under the'Free Arctic'Scenario

    Institute of Scientific and Technical Information of China (English)

    WANG Hui-Jun; ZHANG Ying

    2010-01-01

    This paper addresses the'ice-free Arctic'issue under the future global warming scenario.Four coupled climate models used in the third phase of the Coupled Model Intercomparison Project(CMIP3)were selected to project summer climate conditions over East Asia once the Arctic becomes ice-free.The models project that an ice-free Arctic summer will begin in the 2060s under the SRESA I B(according to IPCC Special Reports on Emissions Scenarios)simulations.Our results show that the East Asian summer monsoons will tend to be stronger and that the water vapor transport to central northern China will be strengthened,leading to increased summer precipitation in central northern China.The models also project an intensified Antarctic Oscillation,a condition which favors increased precipitation in South China's Yangtze River Valley.The overall precipitation in Northwest China is projected to increase under ice-free Arctic summer conditions.

  19. The Arctic Climate Modeling Program: K-12 Geoscience Professional Development for Rural Educators

    Science.gov (United States)

    Bertram, K. B.

    2009-12-01

    Helping teachers and students connect with scientists is the heart of the Arctic Climate Modeling Program (ACMP), funded from 2005-09 by the National Science Foundation’s Innovative Technology Experience for Students and Teachers. ACMP offered progressive yearlong science, technology and math (STM) professional development that prepared teachers to train youth in workforce technologies used in Arctic research. ACMP was created for the Bering Strait School District, a geographically isolated area with low standardized test scores, high dropout rates, and poverty. Scientists from around the globe have converged in this region and other areas of the Arctic to observe and measure changes in climate that are significant, accelerating, and unlike any in recorded history. Climate literacy (the ability to understand Earth system science and to make scientifically informed decisions about climate changes) has become essential for this population. Program resources were designed in collaboration with scientists to mimic the processes used to study Arctic climate. Because the Bering Strait School District serves a 98 percent Alaska Native student population, ACMP focused on best practices shown to increase the success of minority students. Significant research indicates that Alaska Native students succeed academically at higher rates when instruction addresses topics of local interest, links education to the students’ physical and cultural environment, uses local knowledge and culture in the curriculum, and incorporates hands-on, inquiry-based lessons in the classroom. A seven-partner consortium of research institutes and Alaska Native corporations created ACMP to help teachers understand their role in nurturing STM talent and motivating students to explore geoscience careers. Research underscores the importance of increasing school emphasis in content areas, such as climate, that facilitate global awareness and civic responsibility, and that foster critical thinking and

  20. The Endangered Arctic, the Arctic as Resource Frontier: Canadian News Media Narratives of Climate Change and the North.

    Science.gov (United States)

    Stoddart, Mark C J; Smith, Jillian

    2016-08-01

    The Arctic is one of the most radically altered parts of the world due to climate change, with significant social and cultural impacts as a result. Using discourse network analysis and qualitative textual analysis of articles published in the Globe and Mail and National Post during the period 2006 to 2010, we identify and analyze key frames that interpret the implications of climate change on the Arctic. We examine Canadian national news media coverage to ask: How does the Arctic enter media coverage of climate change? Is there evidence of a climate justice discourse in relation to regional disparities in the risks and harms of climate change between northern and southern Canada? Climate change in the Arctic is often framed through the lens of Canadian national interests, which downplays climate-related social impacts that are already occurring at subnational political and geographical scales. L'Arctique est une des régions du monde la plus radicalement altérée par le changement climatique, menant comme résultat des importants changements sociaux et culturels. En utilisant l'analyse des réseaux de discours ainsi que l'analyse textuelle qualitative des articles publiés dans le Globe and Mail et le National Post de 2006 à 2010, nous identifions and analysons des cadres clés qui servent à interpréter les conséquences du changement climatique dans l'Arctique. Nous examinons la couverture des médias nationaux canadiens pour pouvoir demander : comment est-ce que l'Arctique s'insère dans la couverture médiatique du changement climatique? Est-ce qu'il y a de la preuve d'un discours de la justice climatique en relation des disparités régionales des risques et méfaits du changement climatique entre le Canada du nord et du sud? Le changement climatique dans l'Arctique est souvent encadré à travers le prisme des intérêts nationaux canadiens, ce qui minimise les impacts sociaux reliés au climat qui se produisent actuellement aux échelons sous

  1. Using records from submarine, aircraft and satellite to evaluate climate model simulations of Arctic sea ice thickness

    Directory of Open Access Journals (Sweden)

    J. Stroeve

    2014-04-01

    Full Text Available Arctic sea ice thickness distributions from models participating in the World Climate Research Programme Coupled Model Intercomparison Project Phase 5 are evaluated against observations from submarines, aircraft and satellites. While it's encouraging that the mean thickness distributions from the models are in general agreement with observations, the spatial patterns of sea ice thickness are poorly represented in most models. The poor spatial representation of thickness patterns is associated with a failure of models to represent details of the mean atmospheric circulation pattern that governs the transport and spatial distribution of sea ice. The climate models as a whole also tend to underestimate the rate of ice volume loss from 1979 to 2013, though the multi-model ensemble mean trend remains within the uncertainty of that from the Pan-Arctic Ice Ocean Modeling and Assimilation System. These results raise concerns regarding the ability of CMIP5 models to realistically represent the processes driving the decline of Arctic sea ice and project the timing of when a seasonally ice-free Arctic may be realized.

  2. DOE Final Report on Collaborative Research. Quantifying Climate Feedbacks of the Terrestrial Biosphere under Thawing Permafrost Conditions in the Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Qianlai [Purdue Univ., West Lafayette, IN (United States); Schlosser, C. Adam [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Melillo, Jerry M. [Marine Biological Lab. (MBL), Woods Hole, MA (United States); Anthony, Katey Walter [Univ. of Alaska, Fairbanks, AK (United States); Kicklighter, David [Marine Biological Lab. (MBL), Woods Hole, MA (United States); Gao, Xiang [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2015-11-03

    Our overall goal is to quantify the potential for threshold changes in natural emission rates of trace gases, particularly methane and carbon dioxide, from pan-arctic terrestrial systems under the spectrum of anthropogenically-forced climate warming, and the conditions under which these emissions provide a strong feedback mechanism to global climate warming. This goal is motivated under the premise that polar amplification of global climate warming will induce widespread thaw and degradation of the permafrost, and would thus cause substantial changes to the landscape of wetlands and lakes, especially thermokarst (thaw) lakes, across the Arctic. Through a suite of numerical experiments that encapsulate the fundamental processes governing methane emissions and carbon exchanges – as well as their coupling to the global climate system - we intend to test the following hypothesis in the proposed research: There exists a climate warming threshold beyond which permafrost degradation becomes widespread and stimulates large increases in methane emissions (via thermokarst lakes and poorly-drained wetland areas upon thawing permafrost along with microbial metabolic responses to higher temperatures) and increases in carbon dioxide emissions from well-drained areas. Besides changes in biogeochemistry, this threshold will also influence global energy dynamics through effects on surface albedo, evapotranspiration and water vapor. These changes would outweigh any increased uptake of carbon (e.g. from peatlands and higher plant photosynthesis) and would result in a strong, positive feedback to global climate warming.

  3. An energy efficient building for the Arctic climate

    DEFF Research Database (Denmark)

    Vladyková, Petra

    the fundamental definition of a passive house in the Arctic and therefore to save the cost of traditional heating, but that would incur high costs for the building materials and the provision of technical solutions of extremely high standards which would take too many years to pay back in the life time...... in the Arctic needs to take into account also different socioeconomic conditions, building traditions and use of buildings, survival issue, sustainability and power supply, among others. In the Arctic, the energy efficient house based on a passive house concept offers a sustainable solution to the operation...

  4. Climate Prediction Center(CPC)Daily Arctic Oscillation Index

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Arctic Oscillation (AO) is a leading teleconnection pattern in the Northern Hemisphere circulation. It is calculated as the first Empirical Orthogonal Function...

  5. Climate Prediction Center Monthly(CPC)Arctic Oscillation Index

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Arctic Oscillation (AO) is a leading teleconnection pattern in the Northern Hemisphere circulation. It is calculated as the first Empirical Orthogonal Function...

  6. Is "Warm Arctic, Cold Continent" A Fingerprint Pattern of Climate Change?

    Science.gov (United States)

    Hoerling, M. P.; Sun, L.; Perlwitz, J.

    2015-12-01

    Cold winters and cold waves have recently occurred in Europe, central Asia and the Midwest to eastern United States, even as global mean temperatures set record highs and Arctic amplification of surface warming continued. Since 1979, Central Asia winter temperatures have in fact declined. Conjecture has it that more cold extremes over the mid-latitude continents should occur due to global warming and the impacts of Arctic sea ice loss. A Northern Hemisphere temperature signal termed the "Warm Arctic, Cold Continent" pattern has thus been surmised. Here we use a multi-model approach to test the hypothesis that such a pattern is indeed symptomatic of climate change. Diagnosis of a large model ensemble of historical climate simulations shows some individual realizations to yield cooling trends over Central Asia, but importantly the vast majority show warming. The observed cooling has thus likely been a low probability state of internal variability, not a fingerprint of forced climate change. We show that daily temperature variations over continents decline in winter due to global warming, and cold waves become less likely. This is partly related to diminution of Arctic cold air reservoirs due to warming-induced sea ice loss. Nonetheless, we find some evidence and present a physical basis that Arctic sea ice loss alone can induce a winter cooling over Central Asia, though with a magnitude that is appreciably smaller than the overall radiative-forced warming signal. Our results support the argument that recent cooling trends over central Asia, and cold extreme events over the winter continents, have principally resulted from atmospheric internal variability and have been neither a forced response to Arctic seas ice loss nor a symptom of global warming. The paradigm of climate change is thus better expressed as "Warm Arctic, Warm Continent" for the NH winter.

  7. Late Holocene Peat Growth at the Northern Siberian Periphery and its Relation to Arctic Climate Change

    Science.gov (United States)

    Bauch, H. A.; Abramova, E.; Alenius, T.; Saarnisto, M.

    2014-12-01

    During the last postglacial evolution of the shallow northern Siberian shelf systems regional sea level in the Arctic came to its Holocene highstand some time between 5 to 6 ka. After that time a general stabilization of the sedimentary regime occurred. That is well noted in a drastic decrease in sedimentation rates observed in all sediment cores taken from middle to outer shelf water depths of the Laptev Sea. But, at water depths lower than 30 meters - i.e., in the inner shelf and nearer to the coasts - sedimentation continued at relatively higher rates, presumably due to input of terrigenous material from river runoff as well as coastal erosion. Compared with that latter process, the huge Lena Delta should comprise a region of sediment catchment where aggradation wins over erosion. However, little is known about the detailed history of this delta during the second half of the Holocene. In order to gain more insight into this issue we have investigated three islands within the Lena Delta. All of these are comprised of massive peat of several meters in thickness. Picking discrete specimens of water mosses (Sphagnum) only, we have radiocarbon-dated these peat sections. The depth/age relation of the sampled profiles reflect the growth rate of peat. It shows that the islands' history above the present-day delta-sea level is about 4000 yrs. old. Moreover, a significant change in peat growth occurred after 2500 yrs BP in both, accumulation and composition, and allows the conclusion of a major shift in Arctic environmental conditions since then. Thus, our results may add further information also for other coastal studies, as the ongoing degradation of the rather vulnerable permafrost coast in the Laptev Sea and elsewhere along the North Siberian margin is often mentioned in context with recent Arctic climate change due to global warming.

  8. Assessing climate impacts and risks of ocean albedo modification in the Arctic

    Science.gov (United States)

    Mengis, N.; Martin, T.; Keller, D. P.; Oschlies, A.

    2016-05-01

    The ice albedo feedback is one of the key factors of accelerated temperature increase in the high northern latitudes under global warming. This study assesses climate impacts and risks of idealized Arctic Ocean albedo modification (AOAM), a proposed climate engineering method, during transient climate change simulations with varying representative concentration pathway (RCP) scenarios. We find no potential for reversing trends in all assessed Arctic climate metrics under increasing atmospheric CO2 concentrations. AOAM only yields an initial offset during the first years after implementation. Nevertheless, sea ice loss can be delayed by 25(60) years in the RCP8.5(RCP4.5) scenario and the delayed thawing of permafrost soils in the AOAM simulations prevents up to 40(32) Pg of carbon from being released by 2100. AOAM initially dampens the decline of the Atlantic Meridional Overturning and delays the onset of open ocean deep convection in the Nordic Seas under the RCP scenarios. Both these processes cause a subsurface warming signal in the AOAM simulations relative to the default RCP simulations with the potential to destabilize Arctic marine gas hydrates. Furthermore, in 2100, the RCP8.5 AOAM simulation diverts more from the 2005-2015 reference state in many climate metrics than the RCP4.5 simulation without AOAM. Considering the demonstrated risks, we conclude that concerning longer time scales, reductions in emissions remain the safest and most effective way to prevent severe changes in the Arctic.

  9. Low-energy house in Arctic climate - 5 years of experience

    DEFF Research Database (Denmark)

    Vladyková, Petra; Rode, Carsten; Kragh, J.

    2011-01-01

    The aim of this article is to present and disseminate the experience gained from a low‐energy house in Sisimiut, Greenland, over the 5 years of operation since its inauguration in April 2005. The house was designed to test and present new low‐energy technologies in the Arctic climate and to improve...... sustainability in Greenlandic buildings. The article presents some measurements, analyses and comparisons of theoretical simulations, and also some steps which were taken to improve the house with impacts on the energy consumption. The results include energy consumption, temperatures, and solar heating...... production. Also presented are the results of several investigations carried out in the house, such as blower‐door tests and inspection of the ventilation system. The initial target for the heating demand of the house was that it should be restricted to 80 kWh/(m2⋅a), but in reality it has varied over...

  10. Climate Change Effects on Iron Availability to Arctic Phytoplankton

    Science.gov (United States)

    Maldonado, Maria Teresa; Li, Jingxuan; Semeniuk, David; Schuback, Nina; Hoppe, Clara; AWI/UBC Collaboration

    2016-09-01

    Phytoplankton, unicellular algae, are responsible for 50% of earth's photosynthesis, and for a significant consumption of atmospheric CO2. Iron (Fe) is essential for phytoplankton, but is extremely depleted in seawater, limiting photosynthesis in 30% of the global ocean. Oceanic Fe bioavailability is determined by physical and chemical processes. The Arctic Ocean is experiencing the greatest decrease in seawater pH (termed ocean acidification). Simultaneously, ice retreat is promoting higher light intensity in Arctic Ocean. We investigated the effects of ocean acidification and high light on Fe availability to Arctic phytoplankton. Iron uptake rates by plankton, using the radionuclide 55Fe, were used as a proxy for Fe bioavailability. In an Arctic summer research cruise, we measured Fe uptake by two phytoplankton populations subjected to two light levels, as well as present CO2 levels (400ppm) or those expected by 2100 (1100 ppm). Our results demonstrated that high CO2 decreases Fe availability, while high light increases it, suggesting that future Fe bioavailability might be similar to present day. However, the detrimental effects of high CO2 were more pronounced in the plankton population exposed to higher seawater temperature. Future studies should investigate the interaction among light, CO2 and temperature on the Fe physiology of Arctic phytoplankton.

  11. Modelling the impacts of a dipole-like climatic state over the Arctic

    Science.gov (United States)

    Pasha Karami, Mehdi; de Vernal, Anne; Hu, Xianmin; Myers, Paul G.

    2015-04-01

    The Arctic dipole anomaly (ADA) features a pattern with opposite sea-level pressure anomalies over the Canadian Archipelago and the Barents Sea. Changes in the predominance of Arctic atmospheric circulation modes and the shift towards a dipole mode in the past decade played a role in the summer sea ice loss and sea ice-freshwater export from the Arctic to the North Atlantic. Reconstruction of sea ice cover variations during Holocene also suggests opposite anomalies in the Barents Sea versus either the western Arctic or the Fram Strait area similar to the ADA pattern. It is vital to study such physical processes that cause dramatic changes in the Arctic sea ice recalling the link between the ADA and the current climate change. Here we focus on the question of how a persistent ADA-like state affects the Arctic sea ice distribution and its outflow to the Atlantic Ocean. For this purpose, an eddy-permitting regional configuration of the NEMO coupled ocean/sea-ice model is used. The regional domain covers the Arctic Ocean and the Northern-Hemisphere Atlantic, with a horizontal resolution of 1/4 degree at the equator (ANHA4). For the present-day simulations, boundary conditions are obtained by taking the average over the years with a positive ADA and those with a negative ADA. In the Holocene scenario, global climate model data are used to force our regional model. To exclude the role of Bering Strait and the heat flux from the Pacific Ocean, we repeat the experiments with a closed Bering Strait since a nearly closed Bering configuration was possible for the Early Holocene. The model results are compared with the paleoclimate data from Arctic and subarctic seas.

  12. Influence of climate warming on arctic mammals? New insights from ancient DNA studies of the collared lemming Dicrostonyx torquatus.

    Directory of Open Access Journals (Sweden)

    Stefan Prost

    Full Text Available BACKGROUND: Global temperature increased by approximately half a degree (Celsius within the last 150 years. Even this moderate warming had major impacts on Earth's ecological and biological systems, especially in the Arctic where the magnitude of abiotic changes even exceeds those in temperate and tropical biomes. Therefore, understanding the biological consequences of climate change on high latitudes is of critical importance for future conservation of the species living in this habitat. The past 25,000 years can be used as a model for such changes, as they were marked by prominent climatic changes that influenced geographical distribution, demographic history and pattern of genetic variation of many extant species. We sequenced ancient and modern DNA of the collared lemming (Dicrostonyx torquatus, which is a key species of the arctic biota, from a single site (Pymva Shor, Northern Pre Urals, Russia to see if climate warming events after the Last Glacial Maximum had detectable effects on the genetic variation of this arctic rodent species, which is strongly associated with a cold and dry climate. RESULTS: Using three dimensional network reconstructions we found a dramatic decline in genetic diversity following the LGM. Model-based approaches such as Approximate Bayesian Computation and Markov Chain Monte Carlo based Bayesian inference show that there is evidence for a population decline in the collared lemming following the LGM, with the population size dropping to a minimum during the Greenland Interstadial 1 (Bølling/Allerød warming phase at 14.5 kyrs BP. CONCLUSION: Our results show that previous climate warming events had a strong influence on genetic diversity and population size of collared lemmings. Due to its already severely compromised genetic diversity a similar population reduction as a result of the predicted future climate change could completely abolish the remaining genetic diversity in this population. Local population

  13. Response of Arctic Temperature to Changes in Emissions of Short-Lived Climate Forcers

    Science.gov (United States)

    Sand, M.; Berntsen, T.; von Salzen, K.; Flanner, M.; Langner, J.; Victor, D. G.

    2015-12-01

    There is growing scientific and political interest in the impacts of climate change and anthropogenic emissions on the Arctic. Over recent decades temperatures in the Arctic have increased twice the global rate, largely due to ice albedo and temperature feedbacks. While deep cuts in global CO2 emissions are required to slow this warming, there is also growing interest in the potential for reducing short lived climate forcers (SLCFs). Politically, action on SLCFs may be particularly promising because the benefits of mitigation appear promptly and there are large co-benefits in terms of improved air quality. This study is the first to systematically quantify the Arctic climate impact of regional SLCF emissions, taking into account BC, sulphur dioxide (SO2), nitrogen oxides (NOx), volatile hydrocarbons (VOC), organic carbon (OC) and tropospheric ozone, their transport processes and transformations in the atmosphere. Using several chemical transport models we perform detailed radiative forcing calculations from emissions of these species. Geographically we separate emissions into seven source regions that correspond with the national groupings of the Arctic Council, the leading body organizing international policy in the region (the United States, Canada, the Nordic countries, the rest of Europe, Russia, East and South Asia, and the rest of the world). We look at six main sectors known to account for [nearly all] of these emissions: households (domestic), energy/industry/waste, transport, agricultural fires, grass/forest fires, and gas flaring. We find that the largest Arctic warming source is from emissions within the Asian nations. However, the Arctic is most sensitive, per unit mass emitted, to SLCFs emissions from a small number of activities within the Arctic nations themselves. A stringent, but technically feasible SLCFs mitigation scenario, phased in from 2015 through 2030, can cut warming by 0.2 K in 2050.

  14. Interannual climate variations in Arctic as driven by the Global atmosphere oscillation

    Science.gov (United States)

    Serykh, Ilya; Byshev, Vladimir; Neiman, Victor; Sidorova, Alexandra; Sonechkin, Dmitry

    2015-04-01

    The present-day global climate change affects the Arctic basin substantially more because of the sea ice cover extinction and the permafrost melting. But there are essential variations of these effects from year to year. We believe that these variations might be a regional manifestation of a planetary-scale phenomenon named the Global atmospheric oscillation (GAO). GAO includes the well-known El Niño - Southern Oscillation (ENSO) process and similar processes in equatorial Atlantic and Indian Oceans within itself. The goal of this report is to present some arguments to support this point of view. For this goal, we have studied some interrelations between the above-mentioned Arctic anomalies and GAO as seen in global re-analyses of the sea level pressure (SLP) and near surface temperature (NST) for the period of 1920-2013. The mean global fields of SLP and NST have been computed for all El Niño events falling into this time period, and separately, for all and La Niña events. As a result, two (for SLP and NST as well) global fields of the mean El Niño/La Niña difference were obtained. Statistical significance of the non-zero values of these fields, i.e. the reality of GAO, was evaluated with the t-Student's test. It turned out that the main spatial structures of GAO, presented specifically by El Niño and La Niña events in Pacific region, exist at a very high level (up to 99%, t>4) of the significance. Therefore, one can conclude that the interannual-scale dynamics of GAO is actually reflected in the climate features of different regions of the Earth, including the Russian Arctic. In particular, when the boreal winter season coincides with an El Niño event GAO is indicative by a negative anomaly of NST (about -1°C) and a positive anomaly of SLP over the Arctic basin. In contrary, significant (about +1°C) positive anomaly of NST along with reduced SLP over the whole Arctic region is typical for any La Niña event (up to 95%, t>2). To control the reliability

  15. Rethinking Greenland and the Arctic in the Era of Climate Change

    DEFF Research Database (Denmark)

    Sejersen, Frank

    communities engage with climate change and development discourses. It applies a critical and comparative approach, integrating both local perspectives and adaptation research from Canada and Greenland to make the case for recasting the way the Arctic and Inuit are approached conceptually and politically......This book investigates how Arctic indigenous communities deal with the challenges of climate change and how they strive to develop self-determination. Adopting an anthropological focus on Greenland’s vision to boost extractive industries and transform society, the book examines how indigenous....... The emphasis on indigenous peoples as future-makers and right-holders paves the way for a new understanding of the concept of indigenous knowledge and a more sensitive appreciation of predicaments and dynamics in the Arctic....

  16. Changing Permafrost in the Arctic and its Global Effects in the 21st Century (PAGE21): A very large international and integrated project to measure the impact of permafrost degradation on the climate system

    Science.gov (United States)

    Lantuit, Hugues; Boike, Julia; Dahms, Melanie; Hubberten, Hans-Wolfgang

    2013-04-01

    The northern permafrost region contains approximately 50% of the estimated global below-ground organic carbon pool and more than twice as much as is contained in the current atmos-pheric carbon pool. The sheer size of this carbon pool, together with the large amplitude of predicted arctic climate change im-plies that there is a high potential for global-scale feedbacks from arctic climate change if these carbon reservoirs are desta-bilized. Nonetheless, significant gaps exist in our current state of knowledge that prevent us from producing accurate assess-ments of the vulnerability of the arctic permafrost to climate change, or of the implications of future climate change for global greenhouse gas (GHG) emissions. Specifically: • Our understanding of the physical and biogeochemical processes at play in permafrost areas is still insuffi-cient in some key aspects • Size estimates for the high latitude continental carbon and nitrogen stocks vary widely between regions and research groups. • The representation of permafrost-related processes in global climate models still tends to be rudimentary, and is one reason for the frequently poor perform-ances of climate models at high latitudes. The key objectives of PAGE21 are: • to improve our understanding of the processes affect-ing the size of the arctic permafrost carbon and nitro-gen pools through detailed field studies and monitor-ing, in order to quantify their size and their vulnerability to climate change, • to produce, assemble and assess high-quality datasets in order to develop and evaluate representations of permafrost and related processes in global models, • to improve these models accordingly, • to use these models to reduce the uncertainties in feed-backs from arctic permafrost to global change, thereby providing the means to assess the feasibility of stabili-zation scenarios, and • to ensure widespread dissemination of our results in order to provide direct input into the ongoing debate on

  17. On the Role of Arctic Sea Ice Deformations: An Evaluation of the Regional Arctic System Model Results with Observations.

    Science.gov (United States)

    Osinski, Robert; Maslowski, Wieslaw; Roberts, Andrew

    2016-04-01

    The atmosphere - sea ice - ocean fluxes and their contribution to rapid changes in the Arctic system are not well understood and generally are not resolved by global climate models (GCMs). While many significant model refinements have been made in the recent past, including the representation of sea ice rheology, surface albedo and ice-albedo feedback, other processes such as sea ice deformations, still require further studies and model advancements. Of particular potential interest here are linear kinematic features (LKFs), which control winter air-sea heat exchange and affect buoyancy forces in the ocean. Their importance in Arctic climate change, especially under an increasing first-year ice cover, is yet to be determined and their simulation requires representation of processes currently at sub-grid scale of most GCMs. To address some of the GCM limitations and to better understand the role of LKFs in air-sea exchange we use the Regional Arctic System Model (RASM), which allows high spatio-temporal resolution and regional focus on the Arctic. RASM is a fully coupled regional climate model, developed to study dynamic and thermodynamic processes and their coupling across the atmosphere-sea ice-ocean interface. It consists of the Weather Research and Forecasting (WRF) atmospheric model, the Parallel Ocean Program (POP), the Community Ice Model (CICE) and the Variable Infiltration Capacity (VIC) land hydrology model. The sea ice component has been upgraded to the Los Alamos Community Ice Model version 5.1 (CICE5.1), which allows either Elastic-Viscous-Plastic (EVP) or a new anisotropic (EPA) rheology. RASM's domain is pan-Arctic, with the ocean and sea ice components configured at an eddy-permitting horizontal resolution of 1/12-degree as well as 1/48-degree, for limited simulations. The atmosphere and land model components are configured at 50-km grids. All the components are coupled at a 20-minute time step. Results from multiple RASM simulations are analyzed and

  18. Arctic wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Peltola, E. [Kemijoki Oy (Finland); Holttinen, H.; Marjaniemi, M. [VTT Energy, Espoo (Finland); Tammelin, B. [Finnish Meteorological Institute, Helsinki (Finland)

    1998-12-31

    Arctic wind energy research was aimed at adapting existing wind technologies to suit the arctic climatic conditions in Lapland. Project research work included meteorological measurements, instrument development, development of a blade heating system for wind turbines, load measurements and modelling of ice induced loads on wind turbines, together with the development of operation and maintenance practices in arctic conditions. As a result the basis now exists for technically feasible and economically viable wind energy production in Lapland. New and marketable products, such as blade heating systems for wind turbines and meteorological sensors for arctic conditions, with substantial export potential, have also been developed. (orig.)

  19. The climate impacts of absorbing aerosols on and within the Arctic

    Science.gov (United States)

    Rasch, P.; Wang, H.; Ma, P.; Fast, J. D.; Wang, M.; Easter, R. C.; Liu, X.; Qian, Y.; Flanner, M. G.; Ghan, S.; Singh, B.

    2011-12-01

    Absorbing aerosols are receiving increasing attention as forcing agents in the climate system. By scattering and absorbing light they can reduce planetary albedo, particularly over bright surfaces (clouds, snow and ice). They also act as cloud condensation and/or ice nuclei, influencing the brightness, lifetime and precipitation properties of clouds. Atmospheric stability and primary circulation features respond to the changing vertical and horizontal patterns of heating, cooling, and surface fluxes produced by the aerosols, clouds and surface properties. These changes in meteorology have further impacts on aerosols and clouds producing a complex interplay between transport, forcings, and feedbacks involving absorbing aerosols and climate. The complexity of the processes and the interactions between them make it very challenging to represent aerosols realistically in large scale (global and regional) climate models. Simulations of important features of aerosols still contain easily identifiable biases. I will describe our efforts to identify the processes responsible for some of those biases and the deficiencies in model formulations that impede progress in treating aerosols and understanding their role in polar climate. I plan to summarize some studies performed with the NCAR CESM (global) and WRF-Chem (regional) Community models that examine the simulation sensitivity to treatments of physics, chemistry, and meteorology. Some of these simulations were allowed to evolve freely; others were strongly constrained to agree with observed meteorological fields. We have also altered the formulation of a number of the processes in the model to improve fidelity in the aerosol distributions. The parameterizations used in our global model have also been transferred to the regional model, allowing comparisons to be made between the simpler formulations used in the global model with more elaborate and costly formulations available in the regional model. The regional model can

  20. Density and climate influence seasonal population dynamics in an Arctic ungulate

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Moshøj, Charlotte; Forchhammer, Mads C.

    2016-01-01

    The locally migratory behavior of the high arctic muskox (Ovibos muschatus) is a central component of the breeding and winter survival strategies applied to cope with the highly seasonal arctic climate. However, altered climate regimes affecting plant growth are likely to affect local migration...... dynamics of the muskox. In this study, we apply longterm local-scale data on the seasonal distribution of muskoxen in the Zackenberg Valley, Northeast Greenland, to assess the degree of climatic influence on local seasonal muskox dynamics. Specifically, we analyze how seasonal climate (temperature, snow...... cover), forage availability (length of growth season), and the number of adult females available per male (operational sex ratio) influence changes in the seasonal density dependence, abundance, and immigration rate of muskoxen into the valley. The results suggested summer temperature as the major...

  1. Analysis of the Arctic system for freshwater cycle intensification: Observations and expectations

    Science.gov (United States)

    Rawlins, M.A.; Steele, M.; Holland, M.M.; Adam, J.C.; Cherry, J.E.; Francis, J.A.; Groisman, P.Y.; Hinzman, L.D.; Huntington, T.G.; Kane, D.L.; Kimball, J.S.; Kwok, R.; Lammers, R.B.; Lee, C.M.; Lettenmaier, D.P.; McDonald, K.C.; Podest, E.; Pundsack, J.W.; Rudels, B.; Serreze, M.C.; Shiklomanov, A.; Skagseth, O.; Troy, T.J.; Vorosmarty, C.J.; Wensnahan, M.; Wood, E.F.; Woodgate, R.; Yang, D.; Zhang, K.; Zhang, T.

    2010-01-01

    Hydrologic cycle intensification is an expected manifestation of a warming climate. Although positive trends in several global average quantities have been reported, no previous studies have documented broad intensification across elements of the Arctic freshwater cycle (FWC). In this study, the authors examine the character and quantitative significance of changes in annual precipitation, evapotranspiration, and river discharge across the terrestrial pan-Arctic over the past several decades from observations and a suite of coupled general circulation models (GCMs). Trends in freshwater flux and storage derived from observations across the Arctic Ocean and surrounding seas are also described. With few exceptions, precipitation, evapotranspiration, and river discharge fluxes from observations and the GCMs exhibit positive trends. Significant positive trends above the 90% confidence level, however, are not present for all of the observations. Greater confidence in the GCM trends arises through lower interannual variability relative to trend magnitude. Put another way, intrinsic variability in the observations tends to limit confidence in trend robustness. Ocean fluxes are less certain, primarily because of the lack of long-term observations. Where available, salinity and volume flux data suggest some decrease in saltwater inflow to the Barents Sea (i.e., a decrease in freshwater outflow) in recent decades. A decline in freshwater storage across the central Arctic Ocean and suggestions that large-scale circulation plays a dominant role in freshwater trends raise questions as to whether Arctic Ocean freshwater flows are intensifying. Although oceanic fluxes of freshwater are highly variable and consistent trends are difficult to verify, the other components of the Arctic FWC do show consistent positive trends over recent decades. The broad-scale increases provide evidence that the Arctic FWC is experiencing intensification. Efforts that aim to develop an adequate

  2. Population dynamics in the high Arctic: Climate variations in time and space

    DEFF Research Database (Denmark)

    Hendrichsen, Ditte Katrine

    , and to unravel the relative importance of biotic and abiotic factors on ecosystem functioning. This thesis considers how selected vertebrate species in a high Arctic ecosystem respond to climatic variability, using 13 years of data from the monitoring programme at Zackenberg, Northeast Greenland. The main focus...

  3. Arctic Shrub Growth Response to Climate Variation and Infrastructure Development on the North Slope of Alaska

    Science.gov (United States)

    Ackerman, D.; Finlay, J. C.; Griffin, D.

    2015-12-01

    Woody shrub growth in the arctic tundra is increasing on a circumpolar scale. Shrub expansion alters land-atmosphere carbon fluxes, nutrient cycling, and habitat structure. Despite these ecosystem effects, the drivers of shrub expansion have not been precisely established at the landscape scale. This project examined two proposed anthropogenic drivers: global climate change and local infrastructure development, a press disturbance that generates high levels of dust deposition. Effects of global change were studied using dendrochronology to establish a relationship between climate and annual growth in Betula and Salix shrubs growing in the Alaskan low Arctic. To understand the spatial heterogeneity of shrub expansion, this analysis was replicated in shrub populations across levels of landscape properties including soil moisture and substrate age. Effects of dust deposition on normalized difference vegetation index (NDVI) and photosynthetic rate were measured on transects up to 625 meters from the Dalton Highway. Dust deposition rates decreased exponentially with distance from road, matching previous models of road dust deposition. NDVI tracked deposition rates closely, but photosynthetic rates were not strongly affected by deposition. These results suggest that dust deposition may locally bias remote sensing measurements such as NDVI, without altering internal physiological processes such as photosynthesis in arctic shrubs. Distinguishing between the effects of landscape properties, climate, and disturbance will improve our predictions of the biogeochemical feedbacks of arctic shrub expansion, with potential application in climate change modeling.

  4. Does Change in the Arctic Sea Ice Indicate Climate Change? A Lesson Using Geospatial Technology

    Science.gov (United States)

    Bock, Judith K.

    2011-01-01

    The Arctic sea ice has not since melted to the 2007 extent, but annual summer melt extents do continue to be less than the decadal average. Climate fluctuations are well documented by geologic records. Averages are usually based on a minimum of 10 years of averaged data. It is typical for fluctuations to occur from year to year and season to…

  5. Observational uncertainty of Arctic sea-ice concentration significantly affects seasonal climate forecasts

    Science.gov (United States)

    Bunzel, Felix; Notz, Dirk; Baehr, Johanna; Müller, Wolfgang; Fröhlich, Kristina

    2016-04-01

    We examine how the choice of a particular satellite-retrieved sea-ice concentration dataset used for initialising seasonal climate forecasts impacts the prediction skill of Arctic sea-ice area and Northern hemispheric 2-meter air temperatures. To do so, we performed two assimilation runs with the Max Planck Institute Earth System Model (MPI-ESM) from 1979 to 2012, where atmospheric and oceanic parameters as well as sea-ice concentration were assimilated using Newtonian relaxation. The two assimilation runs differ only in the sea-ice concentration dataset used for assimilating sea ice. In the first run, we use sea-ice concentrations as derived by the NASA-Team algorithm, while in the second run we use sea-ice concentrations as derived from the Bootstrap algorithm. A major difference between these two sea-ice concentration data products involves the treatment of melt ponds. While for both products melt ponds appear as open water in the raw satellite data, the Bootstrap algorithm more strongly attempts to offset this systematic bias by synthetically increasing the retrieved ice concentration during summer months. For each year of the two assimilation runs we performed a 10-member ensemble of hindcast experiments starting on 1 May and 1 November with a hindcast length of 6 months. For hindcasts started in November, initial differences in Arctic sea-ice area and surface temperature decrease rapidly throughout the freezing period. For hindcasts started in May, initial sea-ice area differences increase over time. By the end of the melting period, this causes significant differences in 2-meter air temperature of regionally more than 3°C. Hindcast skill for surface temperatures over Europe and North America is higher with Bootstrap initialization during summer and with NASA Team initialisation during winter. This implies that the choice of the sea-ice data product and, thus, the observational uncertainty also affects forecasts of teleconnections that depend on Northern

  6. Wave climate in the Arctic 1992-2014: seasonality, trends, and wave-ice influence

    Science.gov (United States)

    Girard-Ardhuin, Fanny; Stopa, Justin; Ardhuin, Fabrice

    2016-04-01

    The diminishing sea ice has direct implications on the wave field which is mainly dependent on the ice-free area and wind. Over the past decade, the Arctic sea ice has diminished which directly impacts the wave field. This study characterizes the wave climate in the Arctic using detailed sea state information from a wave hindcast and merged altimeter dataset spanning 1992-2014. The waves are driven by winds from the Climate Forecast System Reanalysis. Ice concentrations derived from satellites with a grid spacing of 12.5 km are sufficiently able to resolve important features in the marginal ice zone. Before implementation, suitable wind forcing is identified and the validity and consistency of the wave hindcast is verified with altimeters. The seasonal ice advance and retreat largely dictates the waves and creates distinct features in the wind-waves and swells. The Nordic-Greenland Sea is dominated by swells from the North Atlantic while the coastal regions and semi-enclosed seas of the Kara, Laptev, Chukchi, and Beaufort have a more equal proportion of wind-waves and swells. Trends in the altimeters and model are in agreement and show increasing wave activities in the Baffin Bay, Beaufort, Chukchi, Laptev, and Kara Seas due to the loss of sea ice. In the Nordic-Greenland Sea, there is a decreasing trend related to changes in the wind field by North Atlantic Oscillation. The waves also influence the sea ice. Two distinctly different wave-ice environments are identified and selected events demonstrate the importance of waves in the marginal ice zone. The crux of the research identifies the need for continued study and improvement of wave-ice interaction.

  7. Arctic Security: An Adaptive Approach for a Changing Climate

    Science.gov (United States)

    2009-04-01

    that is most adaptable to change. —Charles Darwin This introductory section provides a brief overview of the problem addressed in this paper and the...temperatures to melting arctic icecaps, from lower crop yields to dying forests , from unforgiving hurricanes to unrelenting droughts, we have no

  8. An evaluation of Arctic cloud and radiation processes during the SHEBA year: simulation results from eight Arctic regional climate models

    Energy Technology Data Exchange (ETDEWEB)

    Wyser, K.; Willen, U. [Rossby Centre, SMHI, Norrkoeping (Sweden); Jones, C.G.; Du, P.; Girard, E.; Laprise, R. [Universite du Quebec a Montreal, Canadian Regional Climate Modelling and Diagnostics Network, Montreal (Canada); Cassano, J.; Serreze, M.; Shaw, M.J. [University of Colorado, Cooperative Institute for Research in Environmental Sciences and Department of Atmospheric and Oceanic Sciences, Boulder, CO (United States); Christensen, J.H. [Danish Meteorological Institute, Copenhagen (Denmark); Curry, J.A. [School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA (United States); Dethloff, K.; Rinke, A. [Alfred Wegener Institute for Polar and Marine Research, Research Unit, Potsdam (Germany); Haugen, J.-E.; Koeltzow, M. [Norwegian Meteorological Institute, Oslo (Norway); Jacob, D.; Pfeifer, S. [Max Planck Institute for Meteorology, Hamburg (Germany); Lynch, A. [Monash University, School of Geography and Environmental Science, Melbourne (Australia); Tjernstroem, M.; Zagar, M. [Stockholm University, Department of Meteorology, Stockholm (Sweden)

    2008-02-15

    Eight atmospheric regional climate models (RCMs) were run for the period September 1997 to October 1998 over the western Arctic Ocean. This period was coincident with the observational campaign of the Surface Heat Budget of the Arctic Ocean (SHEBA) project. The RCMs shared common domains, centred on the SHEBA observation camp, along with a common model horizontal resolution, but differed in their vertical structure and physical parameterizations. All RCMs used the same lateral and surface boundary conditions. Surface downwelling solar and terrestrial radiation, surface albedo, vertically integrated water vapour, liquid water path and cloud cover from each model are evaluated against the SHEBA observation data. Downwelling surface radiation, vertically integrated water vapour and liquid water path are reasonably well simulated at monthly and daily timescales in the model ensemble mean, but with considerable differences among individual models. Simulated surface albedos are relatively accurate in the winter season, but become increasingly inaccurate and variable in the melt season, thereby compromising the net surface radiation budget. Simulated cloud cover is more or less uncorrelated with observed values at the daily timescale. Even for monthly averages, many models do not reproduce the annual cycle correctly. The inter-model spread of simulated cloud-cover is very large, with no model appearing systematically superior. Analysis of the co-variability of terms controlling the surface radiation budget reveal some of the key processes requiring improved treatment in Arctic RCMs. Improvements in the parameterization of cloud amounts and surface albedo are most urgently needed to improve the overall performance of RCMs in the Arctic. (orig.)

  9. Prediction of Arctic plant phenological sensitivity to climate change from historical records.

    Science.gov (United States)

    Panchen, Zoe A; Gorelick, Root

    2017-03-01

    The pace of climate change in the Arctic is dramatic, with temperatures rising at a rate double the global average. The timing of flowering and fruiting (phenology) is often temperature dependent and tends to advance as the climate warms. Herbarium specimens, photographs, and field observations can provide historical phenology records and have been used, on a localised scale, to predict species' phenological sensitivity to climate change. Conducting similar localised studies in the Canadian Arctic, however, poses a challenge where the collection of herbarium specimens, photographs, and field observations have been temporally and spatially sporadic. We used flowering and seed dispersal times of 23 Arctic species from herbarium specimens, photographs, and field observations collected from across the 2.1 million km(2) area of Nunavut, Canada, to determine (1) which monthly temperatures influence flowering and seed dispersal times; (2) species' phenological sensitivity to temperature; and (3) whether flowering or seed dispersal times have advanced over the past 120 years. We tested this at different spatial scales and compared the sensitivity in different regions of Nunavut. Broadly speaking, this research serves as a proof of concept to assess whether phenology-climate change studies using historic data can be conducted at large spatial scales. Flowering times and seed dispersal time were most strongly correlated with June and July temperatures, respectively. Seed dispersal times have advanced at double the rate of flowering times over the past 120 years, reflecting greater late-summer temperature rises in Nunavut. There is great diversity in the flowering time sensitivity to temperature of Arctic plant species, suggesting climate change implications for Arctic ecological communities, including altered community composition, competition, and pollinator interactions. Intraspecific temperature sensitivity and warming trends varied markedly across Nunavut and could

  10. Losing ground: past history and future fate of Arctic small mammals in a changing climate.

    Science.gov (United States)

    Prost, Stefan; Guralnick, Robert P; Waltari, Eric; Fedorov, Vadim B; Kuzmina, Elena; Smirnov, Nickolay; van Kolfschoten, Thijs; Hofreiter, Michael; Vrieling, Klaas

    2013-06-01

    According to the IPCC, the global average temperature is likely to increase by 1.4-5.8 °C over the period from 1990 to 2100. In Polar regions, the magnitude of such climatic changes is even larger than in temperate and tropical biomes. This amplified response is particularly worrisome given that the so-far moderate warming is already impacting Arctic ecosystems. Predicting species responses to rapid warming in the near future can be informed by investigating past responses, as, like the rest of the planet, the Arctic experienced recurrent cycles of temperature increase and decrease (glacial-interglacial changes) in the past. In this study, we compare the response of two important prey species of the Arctic ecosystem, the collared lemming and the narrow-skulled vole, to Late Quaternary climate change. Using ancient DNA and Ecological Niche Modeling (ENM), we show that the two species, which occupy similar, but not identical ecological niches, show markedly different responses to climatic and environmental changes within broadly similar habitats. We empirically demonstrate, utilizing coalescent model-testing approaches, that collared lemming populations decreased substantially after the Last Glacial Maximum; a result consistent with distributional loss over the same period based on ENM results. Given this strong association, we projected the current niche onto future climate conditions based on IPCC 4.0 scenarios, and forecast accelerating loss of habitat along southern range boundaries with likely associated demographic consequences. Narrow-skulled vole distribution and demography, by contrast, was only moderately impacted by past climatic changes, but predicted future changes may begin to affect their current western range boundaries. Our work, founded on multiple lines of evidence suggests a future of rapidly geographically shifting Arctic small mammal prey communities, some of whom are on the edge of existence, and whose fate may have ramifications for the

  11. Projected Impact of Climate Change on the Water and Salt Budgets of the Arctic Ocean by a Global Climate Model

    Science.gov (United States)

    Miller, James R.; Russell, Gary L.

    1996-01-01

    The annual flux of freshwater into the Arctic Ocean by the atmosphere and rivers is balanced by the export of sea ice and oceanic freshwater. Two 150-year simulations of a global climate model are used to examine how this balance might change if atmospheric greenhouse gases (GHGs) increase. Relative to the control, the last 50-year period of the GHG experiment indicates that the total inflow of water from the atmosphere and rivers increases by 10% primarily due to an increase in river discharge, the annual sea-ice export decreases by about half, the oceanic liquid water export increases, salinity decreases, sea-ice cover decreases, and the total mass and sea-surface height of the Arctic Ocean increase. The closed, compact, and multi-phased nature of the hydrologic cycle in the Arctic Ocean makes it an ideal test of water budgets that could be included in model intercomparisons.

  12. Atmospheric transport of persistent organic pollutants to the Arctic, today and in a future climate

    Science.gov (United States)

    Octaviani, Mega; Stemmler, Irene; Lammel, Gerhard

    2013-04-01

    Persistent organic pollutants are of great concern because of their long residence time and long-range transport potential in the environment and because they are readily bioaccumulated along food chains and toxic for wildlife and humans. A multicompartment model is used to study global-scale and long term chemodynamics of anthropogenic organic substances in the Earth system. Model components are the atmosphere (ECHAM5) and ocean general circulation models (MPIOM), which include dynamic sub-models for atmospheric aerosols and the marine biogeochemistry, two-dimensional surface compartments (topsoil, vegetation surfaces, ice, and temporal snow cover) and intercompartmental mass exchange process parameterisations [1-3]. The transports into and out of the Arctic (66° N) are characterized for 1950-2000 under one realisation of present-day climate [4-5] and for 2001-2100 under one realisation of future climate (greenhouse gas emission scenario A1B of IPCC-AR4). Despite decaying primary emissions (since decades) polychlorinated biphenyls (PCB) and dichlorodimephenyltrichloromethane (DDT) are continuing to accumulate in the Arctic, which is fed by atmospheric transports. The main regions of import (and export) are identified and the vertical distribution and seasonalities are characterized. Changes by the end of the 21st century are discussed in the context of a major teleconnection, i.e. the Arctic Oscillation. References [1] Guglielmo F, Lammel G, Maier-Reimer E: Global environmental cycling of DDT and ?-HCH in the 1980s - a study using a coupled atmosphere and ocean general circulation model. Chemosphere 76 (2009) 1509-1517 [2] Stemmler I, Lammel G: Cycling of DDT in the global oceans 1950-2002: World ocean returns the pollutant. Geophys. Res. Lett. 36 (2009) L24602 [3] Hofmann L, Stemmler I, Lammel G: The impact of organochlorines cycling in the cryosphere on their global distributions and fate - 2. Land ice and temporary snow cover. Environ. Pollut. 162 (2012) 482

  13. Projected changes in regional climate extremes arising from Arctic sea ice loss

    Science.gov (United States)

    Screen, James A.; Deser, Clara; Sun, Lantao

    2015-08-01

    The decline in Arctic sea ice cover has been widely documented and it is clear that this change is having profound impacts locally. An emerging and highly uncertain area of scientific research, however, is whether such Arctic change has a tangible effect on weather and climate at lower latitudes. Of particular societal relevance is the open question: will continued Arctic sea ice loss make mid-latitude weather more extreme? Here we analyse idealized atmospheric general circulation model simulations, using two independent models, both forced by projected Arctic sea ice loss in the late twenty-first century. We identify robust projected changes in regional temperature and precipitation extremes arising solely due to Arctic sea ice loss. The likelihood and duration of cold extremes are projected to decrease over high latitudes and over central and eastern North America, but to increase over central Asia. Hot extremes are projected to increase in frequency and duration over high latitudes. The likelihood and severity of wet extremes are projected to increase over high latitudes, the Mediterranean and central Asia; and their intensity is projected to increase over high latitudes and central and eastern Asia. The number of dry days over mid-latitude Eurasia and dry spell duration over high latitudes are both projected to decrease. There is closer model agreement for projected changes in temperature extremes than for precipitation extremes. Overall, we find that extreme weather over central and eastern North America is more sensitive to Arctic sea ice loss than over other mid-latitude regions. Our results are useful for constraining the role of Arctic sea ice loss in shifting the odds of extreme weather, but must not be viewed as deterministic projections, as they do not account for drivers other than Arctic sea ice loss.

  14. Climate warming decreases the survival of the little auk (Alle alle), a high Arctic avian predator

    Science.gov (United States)

    Hovinen, Johanna E H; Welcker, Jorg; Descamps, Sébastien; Strøm, Hallvard; Jerstad, Kurt; Berge, Jørgen; Steen, Harald

    2014-01-01

    Delayed maturity, low fecundity, and high adult survival are traits typical for species with a long-life expectancy. For such species, even a small change in adult survival can strongly affect the population dynamics and viability. We examined the effects of both regional and local climatic variability on adult survival of the little auk, a long-lived and numerous Arctic seabird species. We conducted a mark-resighting study for a period of 8 years (2006-2013) simultaneously at three little auk breeding sites that are influenced by the West Spitsbergen Current, which is the main carrier of warm, Atlantic water into the Arctic. We found that the survival of adult little auks was negatively correlated with both the North Atlantic Oscillation (NAO) index and local summer sea surface temperature (SST), with a time lag of 2 and 1 year, respectively. The effects of NAO and SST were likely mediated through a change in food quality and/or availability: (1) reproduction, growth, and development of Arctic Calanus copepods, the main prey of little auks, are negatively influenced by a reduction in sea ice, reduced ice algal production, and an earlier but shorter lasting spring bloom, all of which result from an increased NAO; (2) a high sea surface temperature shortens the reproductive period of Arctic Calanus, decreasing the number of eggs produced. A synchronous variation in survival rates at the different colonies indicates that climatic forcing was similar throughout the study area. Our findings suggest that a predicted warmer climate in the Arctic will negatively affect the population dynamics of the little auk, a high Arctic avian predator. PMID:25247069

  15. Svalbard Integrated Arctic Earth Observing System (sios): Facilitating Easy Access to Multidisciplinary Arctic Data Through the Brokering Approach.

    Science.gov (United States)

    Bye, B. L.; Godøy, Ø.

    2014-12-01

    Environmental and climate changes are important elements of our global challenges. They are observed at a global scale and in particular in the Arctic. In order to give better estimates of the future changes, the Arctic has to be monitored and analyzed by a multi-disciplinary observation system that will improve Earth System Models. The best chance to achieve significant results within a relatively short time frame is found in regions with a large natural climate gradient, and where processes sensitive to the expected changes are particularly important. Svalbard and the surrounding ocean areas fulfil all these criteria. The vision for SIOS is to be a regional observational system for long term acquisition and proliferation of fundamental knowledge on global environmental change within an Earth System Science perspective in and around Svalbard. SIOS will systematically develop and implement methods for how observational networks are to be construed. The distributed SIOS data management system (SDMS) will be implemented through a combination of technologies tailored to the multi-disciplinary nature of the Arctic data. One of these technologies is The Brokering approach or "Framework". The Brokering approach provides a series of services such as discovery, access, transformation and semantics support to enable translation from one discipline/culture to another. This is exactly the challenges the SDMS will have to handle and thus the Brokering approach is integrated in the design of the system. A description of the design strategy for the SDMS that includes The Brokering approach will be presented. The design and implementation plans for the SDMS are based on research done in the EU funded ESFRI project SIOS and examples of solutions for interoperable systems producing Arctic datasets and products coordinated through SIOS will be showcased. The reported experience from SIOS brokering approach will feed into the process of developing a sustainable brokering governance

  16. Resilience, human agency and climate change adaptation strategies in the Arctic

    DEFF Research Database (Denmark)

    Sejersen, Frank

    2009-01-01

      In the Arctic, indigenous peoples, researchers and governments are working to develop climate change adaptation strategies due to the rapid changes in sea ice extent, weather conditions and in the ecosystem as such. These strategies are often based on specific perceptions of vulnerability...... the political processes taking place in the Arctic: one aspect emphasises stakeholder participation and integration while the other aspect emphasises rightholder possibilites and self-determination. The focus is thus on how adaptation strategies relate to political and legal processes at different scales...

  17. Impact of prescribed Arctic sea ice thickness in simulations of the present and future climate

    Energy Technology Data Exchange (ETDEWEB)

    Krinner, Gerhard [Alfred Wegener Institute for Polar and Marine Research, Potsdam (Germany); INSU-CNRS and UJF Grenoble, Laboratoire de Glaciologie et Geophysique de l' Environnement (LGGE), 54 rue Moliere, BP 96, Saint Martin d' Heres Cedex (France); Rinke, Annette; Dethloff, Klaus [Alfred Wegener Institute for Polar and Marine Research, Potsdam (Germany); Gorodetskaya, Irina V. [INSU-CNRS and UJF Grenoble, Laboratoire de Glaciologie et Geophysique de l' Environnement (LGGE), 54 rue Moliere, BP 96, Saint Martin d' Heres Cedex (France)

    2010-09-15

    This paper describes atmospheric general circulation model climate change experiments in which the Arctic sea-ice thickness is either fixed to 3 m or somewhat more realistically parameterized in order to take into account essentially the spatial variability of Arctic sea-ice thickness, which is, to a first approximation, a function of ice type (perennial or seasonal). It is shown that, both at present and at the end of the twenty-first century (under the SRES-A1B greenhouse gas scenario), the impact of a variable sea-ice thickness compared to a uniform value is essentially limited to the cold seasons and the lower troposphere. However, because first-year ice is scarce in the Central Arctic today, but not under SRES-A1B conditions at the end of the twenty-first century, and because the impact of a sea-ice thickness reduction can be masked by changes of the open water fraction, the spatial and temporal patterns of the effect of sea-ice thinning on the atmosphere differ between the two periods considered. As a consequence, not only the climate simulated at a given period, but also the simulated Arctic climate change over the twenty-first century is affected by the way sea-ice thickness is prescribed. (orig.)

  18. Climate change impacts on wildlife in a High Arctic archipelago - Svalbard, Norway.

    Science.gov (United States)

    Descamps, Sébastien; Aars, Jon; Fuglei, Eva; Kovacs, Kit M; Lydersen, Christian; Pavlova, Olga; Pedersen, Åshild Ø; Ravolainen, Virve; Strøm, Hallvard

    2017-02-01

    The Arctic is warming more rapidly than other region on the planet, and the northern Barents Sea, including the Svalbard Archipelago, is experiencing the fastest temperature increases within the circumpolar Arctic, along with the highest rate of sea ice loss. These physical changes are affecting a broad array of resident Arctic organisms as well as some migrants that occupy the region seasonally. Herein, evidence of climate change impacts on terrestrial and marine wildlife in Svalbard is reviewed, with a focus on bird and mammal species. In the terrestrial ecosystem, increased winter air temperatures and concomitant increases in the frequency of 'rain-on-snow' events are one of the most important facets of climate change with respect to impacts on flora and fauna. Winter rain creates ice that blocks access to food for herbivores and synchronizes the population dynamics of the herbivore-predator guild. In the marine ecosystem, increases in sea temperature and reductions in sea ice are influencing the entire food web. These changes are affecting the foraging and breeding ecology of most marine birds and mammals and are associated with an increase in abundance of several temperate fish, seabird and marine mammal species. Our review indicates that even though a few species are benefiting from a warming climate, most Arctic endemic species in Svalbard are experiencing negative consequences induced by the warming environment. Our review emphasizes the tight relationships between the marine and terrestrial ecosystems in this High Arctic archipelago. Detecting changes in trophic relationships within and between these ecosystems requires long-term (multidecadal) demographic, population- and ecosystem-based monitoring, the results of which are necessary to set appropriate conservation priorities in relation to climate warming.

  19. Polar cloud observatory at Ny-Ålesund in GRENE Arctic Climate Change Research Project

    Science.gov (United States)

    Yamanouchi, Takashi; Takano, Toshiaki; Shiobara, Masataka; Okamoto, Hajime; Koike, Makoto; Ukita, Jinro

    2016-04-01

    Cloud is one of the main processes in the climate system and especially a large feed back agent for Arctic warming amplification (Yoshimori et al., 2014). From this reason, observation of polar cloud has been emphasized and 95 GHz cloud profiling radar in high precision was established at Ny-Ålesund, Svalbard in 2013 as one of the basic infrastructure in the GRENE (Green Network of Excellence Program) Arctic Climate Change Research Project. The radar, "FALCON-A", is a FM-CW (frequency modulated continuous wave) Doppler radar, developed for Arctic use by Chiba University (PI: T. Takano) in 2012, following its prototype, "FALCON-1" which was developed in 2006 (Takano et al., 2010). The specifications of the radar are, central frequency: 94.84 GHz; antenna power: 1 W; observation height: up to 15 km; range resolution: 48 m; beam width: 0.2 degree (15 m at 5 km); Doppler width: 3.2 m/s; time interval: 10 sec, and capable of archiving high sensitivity and high spatial and time resolution. An FM-CW type radar realizes similar sensitivity with much smaller parabolic antennas separated 1.4 m from each other used for transmitting and receiving the wave. Polarized Micro-Pulse Lidar (PMPL, Sigma Space MPL-4B-IDS), which is capable to measure the backscatter and depolarization ratio, has also been deployed to Ny-Ålesund in March 2012, and now operated to perform collocated measurements with FALCON-A. Simultaneous measurement data from collocated PMPL and FALCON-A are available for synergetic analyses of cloud microphysics. Cloud mycrophysics, such as effective radius of ice particles and ice water content, are obtained from the analysis based on algorithm, which is modified for ground-based measurements from Okamoto's retrieval algorithm for satellite based cloud profiling radar and lidar (CloudSat and CALIPSO; Okamoto et al., 2010). Results of two years will be shown in the presentation. Calibration is a point to derive radar reflectivity (dBZ) from original intensity data

  20. Sensitivity of Pliocene Arctic climate to orbital forcing, atmospheric CO2 and sea ice albedo parameterisation

    Science.gov (United States)

    Howell, Fergus W.; Haywood, Alan M.; Dowsett, Harry J.; Pickering, Steven J.

    2016-01-01

    General circulation model (GCM) simulations of the mid-Pliocene Warm Period (mPWP, 3.264 to 3.025 Myr ago) do not reproduce the magnitude of Northern Hemisphere high latitude surface air and sea surface temperature (SAT and SST) warming that proxy data indicate. There is also large uncertainty regarding the state of sea ice cover in the mPWP. Evidence for both perennial and seasonal mPWP Arctic sea ice is found through analyses of marine sediments, whilst in a multi-model ensemble of mPWP climate simulations, half of the ensemble simulated ice-free summer Arctic conditions. Given the strong influence that sea ice exerts on high latitude temperatures, an understanding of the nature of mPWP Arctic sea ice would be highly beneficial.

  1. Arctic climate response to forcing from light-absorbing particles in snow and sea ice in CESM

    Directory of Open Access Journals (Sweden)

    N. Goldenson

    2012-02-01

    Full Text Available The presence of light-absorbing aerosol particles deposited on arctic snow and sea ice influences the surface albedo, causing greater shortwave absorption, warming, and loss of snow and sea ice, lowering the albedo further. The Community Earth System Model version 1 (CESM1 now includes the radiative effects of light-absorbing particles in snow on land and sea ice and in sea ice itself. We investigate the model response to the deposition of black carbon and dust to both snow and sea ice. For these purposes we employ a slab ocean version of CESM1, using the Community Atmosphere Model version 4 (CAM4, run to equilibrium for year 2000 levels of CO2 and fixed aerosol deposition. We construct experiments with and without aerosol deposition, with dust or black carbon deposition alone, and with varying quantities of black carbon and dust to approximate year 1850 and 2000 deposition fluxes. The year 2000 deposition fluxes of both dust and black carbon cause 1–2 °C of surface warming over large areas of the Arctic Ocean and sub-Arctic seas in autumn and winter and in patches of Northern land in every season. Atmospheric circulation changes are a key component of the surface-warming pattern. Arctic sea ice thins by on average about 30 cm. Simulations with year 1850 aerosol deposition are not substantially different from those with year 2000 deposition, given constant levels of CO2. The climatic impact of particulate impurities deposited over land exceeds that of particles deposited over sea ice. Even the surface warming over the sea ice and sea ice thinning depends more upon light-absorbing particles deposited over land. For CO2 doubled relative to year 2000 levels, the climate impact of particulate impurities in snow and sea ice is substantially lower than for the year 2000 equilibrium simulation.

  2. Arctic climate response to forcing from light-absorbing particles in snow and sea ice in CESM

    Directory of Open Access Journals (Sweden)

    N. Goldenson

    2012-09-01

    Full Text Available The presence of light-absorbing aerosol particles deposited on arctic snow and sea ice influences the surface albedo, causing greater shortwave absorption, warming, and loss of snow and sea ice, lowering the albedo further. The Community Earth System Model version 1 (CESM1 now includes the radiative effects of light-absorbing particles in snow on land and sea ice and in sea ice itself. We investigate the model response to the deposition of black carbon and dust to both snow and sea ice. For these purposes we employ a slab ocean version of CESM1, using the Community Atmosphere Model version 4 (CAM4, run to equilibrium for year 2000 levels of CO2 and fixed aerosol deposition. We construct experiments with and without aerosol deposition, with dust or black carbon deposition alone, and with varying quantities of black carbon and dust to approximate year 1850 and 2000 deposition fluxes. The year 2000 deposition fluxes of both dust and black carbon cause 1–2 °C of surface warming over large areas of the Arctic Ocean and sub-Arctic seas in autumn and winter and in patches of Northern land in every season. Atmospheric circulation changes are a key component of the surface-warming pattern. Arctic sea ice thins by on average about 30 cm. Simulations with year 1850 aerosol deposition are not substantially different from those with year 2000 deposition, given constant levels of CO2. The climatic impact of particulate impurities deposited over land exceeds that of particles deposited over sea ice. Even the surface warming over the sea ice and sea ice thinning depends more upon light-absorbing particles deposited over land. For CO2 doubled relative to year 2000 levels, the climate impact of particulate impurities in snow and sea ice is substantially lower than for the year 2000 equilibrium simulation.

  3. A Friend Acting Strangely: an Exhibition on Climate Change in the Arctic

    Science.gov (United States)

    Stauffer, B. W.; Fitzhugh, W. W.; Krupnik, I.; Mannes, J.; Rusk, K.

    2003-12-01

    The Arctic: A Friend Acting Strangely is a new exhibit being developed at the Smithsonian Institution's National Museum of Natural History (NMNH) as a part of the museum's Forces of Change exhibit series on global change issues. The exhibit will open to the public in Summer 2004 and is the third component of the series. The other two components are about El Niño (El Niño's Powerful Reach) and atmospheric chemistry (Change is in the Air). The Arctic exhibit's underlying theme is that current global change is causing such rapid shifts in Arctic weather and the polar environment that it has become `strange,' - or unpredictable - to its residents. The speed of change in Arctic ice and climate patterns, ocean and terrestrial ecosystems, and wildlife creates a great challenge for polar scientists; but it also advances beyond the experience and memory of northern indigenous people, who know it so well. The key issues the NMNH team faces in preparing the new exhibit are: how to document and display the forces and consequences of rapid change; how to make complex scientific processes and research comprehensible to visitors; and how to engage the general public in the on-going discussion. Because current shifts in the Arctic environment have been observed and recorded in much detail by scientists and Native residents alike, this topic offers unique opportunities beyond the museum presentation, including outreach through public programs and the Internet. The exhibit is being developed jointly by the NMNH Arctic Studies Center and Office of the Exhibits, and in close collaboration with NOAA' Office of Arctic Research, NSF' new Study of Environmental Arctic Change (SEARCH) initiative, and NASA's Earth Science Enterprise. Exhibit components will include objects, text, graphic panels, video, and a computer interactive. Special efforts will be made to present the voices and opinions of Arctic indigenous people who experience new challenges to their traditional subsistence

  4. Collaborative Project. Understanding the effects of tides and eddies on the ocean dynamics, sea ice cover and decadal/centennial climate prediction using the Regional Arctic Climate Model (RACM)

    Energy Technology Data Exchange (ETDEWEB)

    Hutchings, Jennifer [Univ. of Alaska, Fairbanks, AK (United States); Joseph, Renu [Univ. of Alaska, Fairbanks, AK (United States)

    2013-09-14

    The goal of this project is to develop an eddy resolving ocean model (POP) with tides coupled to a sea ice model (CICE) within the Regional Arctic System Model (RASM) to investigate the importance of ocean tides and mesoscale eddies in arctic climate simulations and quantify biases associated with these processes and how their relative contribution may improve decadal to centennial arctic climate predictions. Ocean, sea ice and coupled arctic climate response to these small scale processes will be evaluated with regard to their influence on mass, momentum and property exchange between oceans, shelf-basin, ice-ocean, and ocean-atmosphere. The project will facilitate the future routine inclusion of polar tides and eddies in Earth System Models when computing power allows. As such, the proposed research addresses the science in support of the BER’s Climate and Environmental Sciences Division Long Term Measure as it will improve the ocean and sea ice model components as well as the fully coupled RASM and Community Earth System Model (CESM) and it will make them more accurate and computationally efficient.

  5. Tracking Particulate Organic Matter Characteristics in Major Arctic Rivers: Indicators of Watershed-Scale Climate Impacts

    Science.gov (United States)

    McClelland, J. W.; Griffin, C. G.; Holmes, R. M.; Peterson, B. J.; Raymond, P. A.; Spencer, R. G.; Striegl, R. G.; Tank, S. E.

    2015-12-01

    Six large rivers, including the Yukon and Mackenzie in North America and the Yenisey, Ob', Lena, and Kolyma in Eurasia, drain the majority of the watershed area surrounding the Arctic Ocean. Parallel sampling programs were initiated at downstream locations on these rivers in 2003 to improve estimates of fluvial export and track large-scale perturbations associated with climate change. Over a decade later, synthesis of water chemistry data from these ongoing sampling efforts provides an unprecedented opportunity to 1) examine similarities and differences among the major Arctic rivers, and 2) think critically about how changes in various water chemistry parameters may or may not inform us about climate change impacts. River-borne organic matter characteristics may be particularly telling because mass flux values and composition/source indicators vary with hydrology and permafrost coverage. However, separating climate impacts that occur within river corridors from those that occur beyond them may be difficult, especially when considering changes in particulate organic matter (POM) loads. Data on suspended POM yields, C:N ratios, stable isotope ratios, and radiocarbon content in the major Arctic rivers show marked spatial, seasonal, and interannual variability that is helpful for thinking about how climate change effects may manifest in the future, but it will be challenging to separate changes in POM related to bank erosion and suspension/deposition of in situ sediment stocks from changes in POM that may be linked to processes such as permafrost thaw occurring across the broader landscape.

  6. Arctic climate and its interaction with lower latitudes under different levels of anthropogenic warming in a global coupled climate model

    Science.gov (United States)

    Koenigk, Torben; Brodeau, Laurent

    2016-09-01

    Three quasi-equilibrium simulations using constant greenhouse gas forcing corresponding to years 2000, 2015 and 2030 have been performed with the global coupled model EC-Earth in order to analyze the Arctic climate and interactions with lower latitudes under different levels of anthropogenic warming. The model simulations indicate an accelerated warming and ice extent reduction in the Arctic between the year-2030 and year-2015 simulations compared to the change between the year-2015 and year-2000 simulations. Both Arctic warming and sea ice reduction are closely linked to the increase of ocean heat transport into the Arctic, particularly through the Barents Sea Opening. Decadal variations of Arctic sea ice extent and ice volume are of the same order of magnitude as the observed ice extent reductions in the last 30 years and are dominated by the variability of the ocean heat transports through the Barents Sea Opening and the Bering Strait. Despite a general warming of mid and high northern latitudes, a substantial cooling is found in the subpolar gyre of the North Atlantic under year-2015 and year-2030 conditions. This cooling is related to a strong reduction in the AMOC, itself due to reduced deep water formation in the Labrador Sea. The observed trend towards a more negative phase of the North Atlantic Oscillation (NAO) and the observed linkage between autumn Arctic ice variations and NAO are reproduced in our model simulations for selected 30-year periods but are not robust over longer time periods. This indicates that the observed linkages between ice and NAO might not be robust in reality either, and that the observational time period is still too short to reliably separate the trend from the natural variability.

  7. Land-Cover and Land-Use Change under Changing Climate in the Eurasian Arctic

    Science.gov (United States)

    Gutman, G.

    2009-04-01

    An overview of the studies conducted in the framework of the NASA Land-Cover/Land- Use Change Program focused on the Eurasian Arctic will be presented. It includes discussion of vegetation changes under climate warming and implications to carbon cycle, changes in environmental pollution, hydrologic cycle, and impacts on society. Climate change can affect land cover in the Arctic through changes in the surface reflectivity and hydrology due to changes in snow melt timing; impacts of black carbon emitted by fires and settled on bright surfaces; changes in sea ice and the consequent change in ocean circulation affecting vegetation cover patterns indirectly; and changes in the amounts of greenhouse gases emission due to permafrost melting, especially in peatlands, as warming progresses. The Arctic Eurasia is being affected by global and regional external factors that are causing its change and the positive feedbacks to this forcing may further exaggerate the situation. If the warming trend continues it will have a tremendous impact on all aspects of land cover in the Arctic region with considerable consequences at the global scale. It will cause significant changes in the natural land cover, and perhaps even greater changes in the areas where the land cover has already been considerably modified by human activities. Major changes have already taken place in how land is used in the Arctic. In many regions, there has been a clear shift from the land use practiced by indigenous people to intensive exploitation of the land for commercial and industrial uses. Results on the climate/environment - land-cover interactions will be presented.

  8. Climatic and biotic extreme events moderate long-term responses of above- and belowground sub-Arctic heathland communities to climate change

    NARCIS (Netherlands)

    Bokhorst, Stef; Phoenix, Gareth K.; Berg, Matty P.; Callaghan, Terry V.; Kirby-Lambert, Christopher; Bjerke, Jarle W.

    2015-01-01

    Climate change impacts are not uniform across the Arctic region because interacting factors causes large variations in local ecosystem change. Extreme climatic events and population cycles of herbivores occur simultaneously against a background of gradual climate warming trends and can redirect ecos

  9. Short-lived pollutants in the Arctic: their climate impact and possible mitigation strategies

    Energy Technology Data Exchange (ETDEWEB)

    Menon, Surabi; Quinn, P.K.; Bates, T.S.; Baum, E.; Doubleday, N.; Fiore, A.M.; Flanner, M.; Fridlind, A.; Garrett, T.J.; Koch, D.; Menon, S.; Shindell, D.; Stohl, A.; Warren, S.G.

    2007-09-24

    Several short-lived pollutants known to impact Arctic climate may be contributing to the accelerated rates of warming observed in this region relative to the global annually averaged temperature increase. Here, we present a summary of the short-lived pollutants that impact Arctic climate including methane, tropospheric ozone, and tropospheric aerosols. For each pollutant, we provide a description of the major sources and the mechanism of forcing. We also provide the first seasonally averaged forcing and corresponding temperature response estimates focused specifically on the Arctic. The calculations indicate that the forcings due to black carbon, methane, and tropospheric ozone lead to a positive surface temperature response indicating the need to reduce emissions of these species within and outside the Arctic. Additional aerosol species may also lead to surface warming if the aerosol is coincident with thin, low lying clouds. We suggest strategies for reducing the warming based on current knowledge and discuss directions for future research to address the large remaining uncertainties.

  10. Short-term Climate Characteristics at Ny-(A)lesund over the Arctic Tundra Area

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Based on the Germany Koldwey Station's 1994-2003 conventional observation hourly data, this paper conducts a statistical analysis on the short-term climate characteristics for an arctic tundra region (Ny-(A)lesund island) where our first arctic expedition station (Huanghe Station) was located. Affected by the North Atlantic warming current, this area has a humid temperate climate, and the air temperature at Ny-(A)lesund rose above 0 ℃ even during deep winter season during our research period. The wind speed in this area was low and appeared most at southeast direction. We find that the temperature at Ny-(A)lesund rose in the faster rate (0.68 ℃/10 a) than those at the whole Arctic area. Compared with the floating ices where our expedition conducted in the Arctic, Ny-(A)lesund was warmer and more humid and had lower wind speed. Comparison of the near surface air temperature derived by NCEP/NCAR reanalysis to the conventional measurements conducted at the Koldwey site in Ny-(A)lesund area shows a good agreement for winter season and a significant difference for summer season.

  11. Arctic ice management

    Science.gov (United States)

    Desch, Steven J.; Smith, Nathan; Groppi, Christopher; Vargas, Perry; Jackson, Rebecca; Kalyaan, Anusha; Nguyen, Peter; Probst, Luke; Rubin, Mark E.; Singleton, Heather; Spacek, Alexander; Truitt, Amanda; Zaw, Pye Pye; Hartnett, Hilairy E.

    2017-01-01

    As the Earth's climate has changed, Arctic sea ice extent has decreased drastically. It is likely that the late-summer Arctic will be ice-free as soon as the 2030s. This loss of sea ice represents one of the most severe positive feedbacks in the climate system, as sunlight that would otherwise be reflected by sea ice is absorbed by open ocean. It is unlikely that CO2 levels and mean temperatures can be decreased in time to prevent this loss, so restoring sea ice artificially is an imperative. Here we investigate a means for enhancing Arctic sea ice production by using wind power during the Arctic winter to pump water to the surface, where it will freeze more rapidly. We show that where appropriate devices are employed, it is possible to increase ice thickness above natural levels, by about 1 m over the course of the winter. We examine the effects this has in the Arctic climate, concluding that deployment over 10% of the Arctic, especially where ice survival is marginal, could more than reverse current trends of ice loss in the Arctic, using existing industrial capacity. We propose that winter ice thickening by wind-powered pumps be considered and assessed as part of a multipronged strategy for restoring sea ice and arresting the strongest feedbacks in the climate system.

  12. Biogeophysical feedbacks enhance Arctic terrestrial carbon sink in regional Earth system dynamics

    Directory of Open Access Journals (Sweden)

    W. Zhang

    2014-05-01

    Full Text Available Continued warming of the Arctic will likely accelerate terrestrial carbon (C cycling by increasing both uptake and release of C. There are still large uncertainties in modelling Arctic terrestrial ecosystems as a source or sink of C. Most modelling studies assessing or projecting the future fate of C exchange with the atmosphere are based an either stand-alone process-based models or coupled climate–C cycle general circulation models, in either case disregarding biogeophysical feedbacks of land surface changes to the atmosphere. To understand how biogeophysical feedbacks will impact on both climate and C budget over Arctic terrestrial ecosystems, we apply the regional Earth system model RCA-GUESS over the CORDEX-Arctic domain. The model is forced with lateral boundary conditions from an GCMs CMIP5 climate projection under the RCP 8.5 scenario. We perform two simulations with or without interactive vegetation dynamics respectively to assess the impacts of biogeophysical feedbacks. Both simulations indicate that Arctic terrestrial ecosystems will continue to sequester C with an increased uptake rate until 2060s–2070s, after which the C budget will return to a weak C sink as increased soil respiration and biomass burning outpaces increased net primary productivity. The additional C sinks arising from biogeophysical feedbacks are considerable, around 8.5 Gt C, accounting for 22% of the total C sinks, of which 83.5% are located in areas of Arctic tundra. Two opposing feedback mechanisms, mediated by albedo and evapotranspiration changes respectively, contribute to this response. Albedo feedback dominates over winter and spring season, amplifying the near-surface warming by up to 1.35 K in spring, while evapotranspiration feedback dominates over summer exerting the evaporative cooling by up to 0.81 K. Such feedbacks stimulate vegetation growth with an earlier onset of growing-season, leading to compositional changes in woody plants and vegetation

  13. Signs of the Land: Reaching Arctic Communities Facing Climate Change

    Science.gov (United States)

    Sparrow, E. B.; Chase, M. J.; Demientieff, S.; Pfirman, S. L.; Brunacini, J.

    2014-12-01

    In July 2014, a diverse and intergenerational group of Alaskan Natives came together on Howard Luke's Galee'ya Camp by the Tanana River in Fairbanks, Alaska to talk about climate change and it's impacts on local communities. Over a period of four days, the Signs of the Land Climate Change Camp wove together traditional knowledge, local observations, Native language, and climate science through a mix of storytelling, presentations, dialogue, and hands-on, community-building activities. This camp adapted the model developed several years ago under the Association for Interior Native Educators (AINE)'s Elder Academy. Part of the Polar Learning and Responding Climate Change Education Partnership, the Signs of the Land Climate Change Camp was developed and conducted collaboratively with multiple partners to test a model for engaging indigenous communities in the co-production of climate change knowledge, communication tools, and solutions-building. Native Alaskans have strong subsistence and cultural connections to the land and its resources, and, in addition to being keen observers of their environment, have a long history of adapting to changing conditions. Participants in the camp included Elders, classroom teachers, local resource managers and planners, community members, and climate scientists. Based on their experiences during the camp, participants designed individualized outreach plans for bringing culturally-responsive climate learning to their communities and classrooms throughout the upcoming year. Plans included small group discussions, student projects, teacher training, and conference presentations.

  14. Ecosystem responses to climate change at a Low Arctic and a High Arctic long-term research site.

    Science.gov (United States)

    Hobbie, John E; Shaver, Gaius R; Rastetter, Edward B; Cherry, Jessica E; Goetz, Scott J; Guay, Kevin C; Gould, William A; Kling, George W

    2017-02-01

    Long-term measurements of ecological effects of warming are often not statistically significant because of annual variability or signal noise. These are reduced in indicators that filter or reduce the noise around the signal and allow effects of climate warming to emerge. In this way, certain indicators act as medium pass filters integrating the signal over years-to-decades. In the Alaskan Arctic, the 25-year record of warming of air temperature revealed no significant trend, yet environmental and ecological changes prove that warming is affecting the ecosystem. The useful indicators are deep permafrost temperatures, vegetation and shrub biomass, satellite measures of canopy reflectance (NDVI), and chemical measures of soil weathering. In contrast, the 18-year record in the Greenland Arctic revealed an extremely high summer air-warming of 1.3 °C/decade; the cover of some plant species increased while the cover of others decreased. Useful indicators of change are NDVI and the active layer thickness.

  15. Arctic Legal System: a New Sustainable Development Model

    Directory of Open Access Journals (Sweden)

    Kumar Sahu Manjeet

    2016-01-01

    Full Text Available Historically, the term ‘Arctic’ was used synonymously with the term ‘ice’, but climate change and Arctic hydrocarbon grabbed the attention of the world community as an opportunity to make the Arctic an ‘Energy Hub’. Exploration of oil and gas over the past six decades in the Arctic has made the region as places in the world. All major players in the market have endeavored to approach this new energy basket to utilize its maximum benefit. Commercial exploitation of natural resources has made this place a center for the regulation of oil and gas activities. However, petroleum exploration and its operation have had significant local detrimental impacts on the atmosphere, inhabitants and marine environment. Geologists have always believed in the huge reserves of oil and gas in the Arctic Region. However, the exploration of oil and gas started as recently as the mid-1950s. An increase in the demand of oil and gas in the international market, as well as its growing scarcity, compelled the world to locate oil and gas reserves in various regions. It is significant to note that the Arctic states are strategically going to control the excessive exploitation of Arctic hydrocarbon with much profitability. However, it is still a far sighted question ‘whether Arctic will provide direct competition to the Middle East’ and become another hub in the energy market.

  16. Climate change and environmental impacts on maternal and newborn health with focus on Arctic populations

    Directory of Open Access Journals (Sweden)

    Torkjel M. Sandanger

    2011-11-01

    Full Text Available In 2007, the Intergovernmental Panel on Climate Change (IPCC presented a report on global warming and the impact of human activities on global warming. Later the Lancet commission identified six ways human health could be affected. Among these were not environmental factors which are also believed to be important for human health. In this paper we therefore focus on environmental factors, climate change and the predicted effects on maternal and newborn health. Arctic issues are discussed specifically considering their exposure and sensitivity to long range transported contaminants.Considering that the different parts of pregnancy are particularly sensitive time periods for the effects of environmental exposure, this review focuses on the impacts on maternal and newborn health. Environmental stressors known to affects human health and how these will change with the predicted climate change are addressed. Air pollution and food security are crucial issues for the pregnant population in a changing climate, especially indoor climate and food security in Arctic areas.The total number of environmental factors is today responsible for a large number of the global deaths, especially in young children. Climate change will most likely lead to an increase in this number. Exposure to the different environmental stressors especially air pollution will in most parts of the world increase with climate change, even though some areas might face lower exposure. Populations at risk today are believed to be most heavily affected. As for the persistent organic pollutants a warming climate leads to a remobilisation and a possible increase in food chain exposure in the Arctic and thus increased risk for Arctic populations. This is especially the case for mercury. The perspective for the next generations will be closely connected to the expected temperature changes; changes in housing conditions; changes in exposure patterns; predicted increased exposure to Mercury

  17. Norwegian Arctic climate. Climate influencing emissions, scenarios and mitigation options at Svalbard

    Energy Technology Data Exchange (ETDEWEB)

    Vestreng, Vigdis; Kallenborn, Roland; Oekstad, Elin

    2010-07-01

    The goal of this study was to establish an emission inventory and emission scenarios for climate influencing compounds at Svalbard, as a basis to develop strategies for emission reduction measures and policies. Emissions for the years 2000-2007 have been estimated for the Svalbard Zone. This area, covering about 173 000 km{sub 2}, ranges from 10 E to 35 E longitude and 74 N to 81 N latitude (Figure 1). In addition, air and ship transport between Tromsoe at the Norwegian mainland and Svalbard has been included. Pollutants considered in our inventory are carbon dioxide (CO{sub 2}), methane (CH{sub 4}), Sulphur dioxide (SO{sub 2}), Nitrogen oxides (NO{sub x} as NO{sub 2}), and for the first time also estimates of black carbon (BC, soot) and organic carbon (OC) have been included. Our results show that emissions of all pollutants have increased over the time span 2000-2007 (Figure 2), and are expected to increase also in the future if additional measures are not implemented (Figure 12). The emissions from Svalbard are minuscule compared to emission released from the Norwegian mainland and waters (1% in the case of CO{sub 2}). Even so, local releases of climate influencing compounds in the vulnerable Arctic may turn out to make a difference both with respect to adverse environmental effects and to climate change. Emissions have been estimated for all activities of any significance taking place at and around Svalbard. Combustion sources as well as fugitive emissions of methane are included. The main sectors are coal mining, energy production and transportation. Pollution from 28 sub sectors related to these activities has been estimated. The scope of this work differs from that covered by national inventories since emission estimates are based on the fuel consumed and include emissions from international shipping and aviation. Fuel consumption data were collected from local authorities, institutions and industry. Emission factors have been selected from relevant

  18. Norwegian Arctic climate. Climate influencing emissions, scenarios and mitigation options at Svalbard

    Energy Technology Data Exchange (ETDEWEB)

    Vestreng, Vigdis; Kallenborn, Roland; Oekstad, Elin

    2010-07-01

    The goal of this study was to establish an emission inventory and emission scenarios for climate influencing compounds at Svalbard, as a basis to develop strategies for emission reduction measures and policies. Emissions for the years 2000-2007 have been estimated for the Svalbard Zone. This area, covering about 173 000 km{sub 2}, ranges from 10 E to 35 E longitude and 74 N to 81 N latitude (Figure 1). In addition, air and ship transport between Tromsoe at the Norwegian mainland and Svalbard has been included. Pollutants considered in our inventory are carbon dioxide (CO{sub 2}), methane (CH{sub 4}), Sulphur dioxide (SO{sub 2}), Nitrogen oxides (NO{sub x} as NO{sub 2}), and for the first time also estimates of black carbon (BC, soot) and organic carbon (OC) have been included. Our results show that emissions of all pollutants have increased over the time span 2000-2007 (Figure 2), and are expected to increase also in the future if additional measures are not implemented (Figure 12). The emissions from Svalbard are minuscule compared to emission released from the Norwegian mainland and waters (1% in the case of CO{sub 2}). Even so, local releases of climate influencing compounds in the vulnerable Arctic may turn out to make a difference both with respect to adverse environmental effects and to climate change. Emissions have been estimated for all activities of any significance taking place at and around Svalbard. Combustion sources as well as fugitive emissions of methane are included. The main sectors are coal mining, energy production and transportation. Pollution from 28 sub sectors related to these activities has been estimated. The scope of this work differs from that covered by national inventories since emission estimates are based on the fuel consumed and include emissions from international shipping and aviation. Fuel consumption data were collected from local authorities, institutions and industry. Emission factors have been selected from relevant

  19. Climate change and infectious diseases in the Arctic

    DEFF Research Database (Denmark)

    Parkinson, Alan J; Evengard, Birgitta; Semenza, Jan C

    2014-01-01

    animals. Potentially climate-sensitive zoonotic pathogens of circumpolar concern include Brucella spp., Toxoplasma gondii, Trichinella spp., Clostridium botulinum, Francisella tularensis, Borrelia burgdorferi, Bacillus anthracis, Echinococcus spp., Leptospira spp., Giardia spp., Cryptosporida spp...

  20. Recent climate change in the Arctic and its impact on contaminant pathways and interpretation of temporal trend data.

    Science.gov (United States)

    Macdonald, R W; Harner, T; Fyfe, J

    2005-04-15

    possibility, presently difficult to predict, is combination of immune suppression together with expanding ranges of disease vectors. Finally, biotransport through migratory species is exceptionally vulnerable to changes in migration strength or in migration pathway-in the Arctic, change in the distribution of ice and temperature may already have caused such changes. Hydrocarbons, which tend to impact surfaces, will be mostly affected by change in the ice climate (distribution and drift tracks). Perhaps the most dramatic changes will occur because our view of the Arctic Ocean will change as it becomes more amenable to transport, tourism and mineral exploration on the shelves. Radionuclides have tended not to produce a radiological problem in the Arctic; nevertheless one pathway, the ice, remains a risk because it can accrue, concentrate and transport radio-contaminated sediments. This pathway is sensitive to where ice is produced, what the transport pathways of ice are, and where ice is finally melted-all strong candidates for change during the coming century. The changes that have already occurred in the Arctic and those that are projected to occur have an effect on contaminant time series including direct measurements (air, water, biota) or proxies (sediment cores, ice cores, archive material). Although these 'system' changes can alter the flux and concentrations at given sites in a number of obvious ways, they have been all but ignored in the interpretation of such time series. To understand properly what trends mean, especially in complex 'recorders' such as seals, walrus and polar bears, demands a more thorough approach to time series by collecting data in a number of media coherently. Presently, a major reservoir for contaminants and the one most directly connected to biological uptake in species at greatest risk-the ocean-practically lacks such time series.

  1. Recent climate change in the Arctic and its impact on contaminant pathways and interpretation of temporal trend data

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, R.W. [Institute of Ocean Sciences, Department of Fisheries and Oceans, P.O. Box 6000, Sydney, BC (Canada); Harner, T. [Meteorological Service of Canada, Environment Canada, 4905 Dufferin Street, Downsview, ON (Canada); Fyfe, J. [Meteorological Service of Canada, Centre for Climate Modelling and Analysis, 3964 Gordon Head Road, Victoria, BC (Canada)

    2005-04-15

    possibility, presently difficult to predict, is combination of immune suppression together with expanding ranges of disease vectors. Finally, biotransport through migratory species is exceptionally vulnerable to changes in migration strength or in migration pathway-in the Arctic, change in the distribution of ice and temperature may already have caused such changes. Hydrocarbons, which tend to impact surfaces, will be mostly affected by change in the ice climate (distribution and drift tracks). Perhaps the most dramatic changes will occur because our view of the Arctic Ocean will change as it becomes more amenable to transport, tourism and mineral exploration on the shelves. Radionuclides have tended not to produce a radiological problem in the Arctic; nevertheless one pathway, the ice, remains a risk because it can accrue, concentrate and transport radio-contaminated sediments. This pathway is sensitive to where ice is produced, what the transport pathways of ice are, and where ice is finally melted-all strong candidates for change during the coming century. The changes that have already occurred in the Arctic and those that are projected to occur have an effect on contaminant time series including direct measurements (air, water, biota) or proxies (sediment cores, ice cores, archive material). Although these 'system' changes can alter the flux and concentrations at given sites in a number of obvious ways, they have been all but ignored in the interpretation of such time series. To understand properly what trends mean, especially in complex 'recorders' such as seals, walrus and polar bears, demands a more thorough approach to time series by collecting data in a number of media coherently. Presently, a major reservoir for contaminants and the one most directly connected to biological uptake in species at greatest risk-the ocean-practically lacks such time series.

  2. Arctic sea ice area in CMIP3 and CMIP5 climate model ensembles - variability and change

    Science.gov (United States)

    Semenov, V. A.; Martin, T.; Behrens, L. K.; Latif, M.

    2015-02-01

    The shrinking Arctic sea ice cover observed during the last decades is probably the clearest manifestation of ongoing climate change. While climate models in general reproduce the sea ice retreat in the Arctic during the 20th century and simulate further sea ice area loss during the 21st century in response to anthropogenic forcing, the models suffer from large biases and the model results exhibit considerable spread. The last generation of climate models from World Climate Research Programme Coupled Model Intercomparison Project Phase 5 (CMIP5), when compared to the previous CMIP3 model ensemble and considering the whole Arctic, were found to be more consistent with the observed changes in sea ice extent during the recent decades. Some CMIP5 models project strongly accelerated (non-linear) sea ice loss during the first half of the 21st century. Here, complementary to previous studies, we compare results from CMIP3 and CMIP5 with respect to regional Arctic sea ice change. We focus on September and March sea ice. Sea ice area (SIA) variability, sea ice concentration (SIC) variability, and characteristics of the SIA seasonal cycle and interannual variability have been analysed for the whole Arctic, termed Entire Arctic, Central Arctic and Barents Sea. Further, the sensitivity of SIA changes to changes in Northern Hemisphere (NH) averaged temperature is investigated and several important dynamical links between SIA and natural climate variability involving the Atlantic Meridional Overturning Circulation (AMOC), North Atlantic Oscillation (NAO) and sea level pressure gradient (SLPG) in the western Barents Sea opening serving as an index of oceanic inflow to the Barents Sea are studied. The CMIP3 and CMIP5 models not only simulate a coherent decline of the Arctic SIA but also depict consistent changes in the SIA seasonal cycle and in the aforementioned dynamical links. The spatial patterns of SIC variability improve in the CMIP5 ensemble, particularly in summer. Both

  3. Tourism and Arctic Observation Systems: exploring the relationships

    Directory of Open Access Journals (Sweden)

    Suzanne de la Barre

    2016-03-01

    Full Text Available The Arctic is affected by global environmental change and also by diverse interests from many economic sectors and industries. Over the last decade, various actors have attempted to explore the options for setting up integrated and comprehensive trans-boundary systems for monitoring and observing these impacts. These Arctic Observation Systems (AOS contribute to the planning, implementation, monitoring and evaluation of environmental change and responsible social and economic development in the Arctic. The aim of this article is to identify the two-way relationship between AOS and tourism. On the one hand, tourism activities account for diverse changes across a broad spectrum of impact fields. On the other hand, due to its multiple and diverse agents and far-reaching activities, tourism is also well-positioned to collect observational data and participate as an actor in monitoring activities. To accomplish our goals, we provide an inventory of tourism-embedded issues and concerns of interest to AOS from a range of destinations in the circumpolar Arctic region, including Alaska, Arctic Canada, Iceland, Svalbard, the mainland European Arctic and Russia. The article also draws comparisons with the situation in Antarctica. On the basis of a collective analysis provided by members of the International Polar Tourism Research Network from across the polar regions, we conclude that the potential role for tourism in the development and implementation of AOS is significant and has been overlooked.

  4. Climate Change Experiments in Arctic Ecosystems: Scientific Strategy and Design Criteria

    Science.gov (United States)

    Wullschleger, S. D.; Hinzman, L. D.; McGuire, A. D.; Oberbauer, S. F.; Oechel, W. C.; Norby, R. J.; Thornton, P. E.; Schuur, E. A.; Shugart, H. H.; Walsh, J. E.; Wilson, C. J.

    2010-12-01

    Arctic and subarctic ecosystems are sensitive to changes in climate. These are among the largest and coldest of all ecosystems and are perceived by many as especially vulnerable to environmental change. Warming, in particular, is expected to be greatest in northern latitudes with potentially significant consequences for tundra, taiga, and peat lands. Observational evidence suggests that warming is already affecting physical and ecological processes in high-latitude ecosystems. Models predict that permafrost degradation and the northward expansion of shrubs into tundra represent important feedbacks on climate. Manipulative experiments can help understand the vulnerability of ecosystems to climate warming. Previous attempts to manipulate the environment of ecosystems in arctic and subarctic regions have focused on warming plant and soils, but treatments have been limited to small scales and modest increases in temperature. Manipulating the environment at larger scales and exposing ecosystems to higher temperatures for longer periods of time will be required to fully describe the physical, chemical, and biological mechanisms that govern land-atmosphere interactions. A variety of logistical and engineering challenges must be overcome and new approaches developed before we can address the questions being asked of the scientific community especially as we continue to move toward large-scale and long-term experiments. In light of the many uncertainties that surround the response of high-latitude ecosystems to global climate change, it is important that the scientific community consider how manipulative experiments can address and resolve ecosystem impacts and feedbacks to climate. A workshop sponsored by the Department of Energy, Office of Science was recently held at the University of Alaska, Fairbanks. The goal of the workshop was to highlight conclusions from observational and modeling studies about the response of arctic and subarctic ecosystems to a changing climate

  5. Climate impacts of shipping and petroleum extraction in an unlocked Arctic ocean

    Science.gov (United States)

    Samset, B. H.; Berntsen, T.; Dahlsøren, S. B.; Eide, L. I.; Eide, M. S.; Fuglestvedt, J.; Glomsrød, S.; Lindholt, L.; Myhre, G.; Nilssen, T. B.; Peters, G. P.; Ødemark, K.

    2012-04-01

    Reductions in sea ice extent are expected to open up the Arctic region to increased volumes of ship traffic and petroleum extraction activities. Both of these potentially entail changes in concentrations of short-lived climate forcers (SLCFs) such as aerosols and ozone, which may impact the future climate. The response of the Arctic to SLCF emissions is however not well constrained, as the annual cycle, solar irradiation, surface albedo and ambient temperature are special to this region. The present study investigates the effects of SLCF emissions in the Arctic in 2004, as well as in 2030 and 2050. An emission inventory is used for present day activities, while future emissions are taken from models of the global energy market and shipping fleet. Atmospheric concentrations are input to the OsloCTM2 chemical transport model, and radiative forcings (RFs) are calculated using a multi-stream radiation transport code. Climate impacts are quantified via RFs and Global Warming Potentials of the various emitted components, in addition to estimates of the first indirect aerosol effect and the snow albedo effect from black carbon (BC). For present day emissions we calculate a net negative RF from shipping, mainly driven by the indirect aerosol effect, and a net positive RF from petroleum extraction, mainly due to the BC snow albedo effect. For future emissions the general results remain similar, but the total RFs develop with changes in emission volume and composition. We discuss the sensitivity of the Arctic region to emissions in terms of normalized RFs as function of season and geographical location.

  6. CLIMATE CHANGE AND VULNERABILITY OF THE ARCTIC ELDERLY: AN ASSESSMENT FROM HUMAN RIGHTS POINT OF VIEW

    Directory of Open Access Journals (Sweden)

    Shahnaj Begum

    2012-10-01

    Full Text Available There are increasing challenges among the elderly in the Arctic region. Global warming due to climate change is one of the major reasons for these challenges. Because of climate change temperature in the region increases, which results in rapid melting of sea ice causing various environmental, social, cultural and economic problems. Population in the region suffers from these problems where elderly people are the most vulnerable. Climate change has already affected the elderly lives in different ways, such as, by physical, social, political, cultural and psychological ways. These have serious consequences in terms of human rights of this vulnerable group of people. However, the elderly people’s human rights issues have not been adequately researched in the context of this region. The goal of this paper is to present elderly related human rights issues, particularly the rights that are affected due to climate change in this specific region.

  7. Reconstruction of climate dynamics in an Arctic fjord environment: evidence from a multi-proxy high resolution marine record.

    Science.gov (United States)

    MacLachlan, S. E.; Howe, J.

    2012-12-01

    The cryosphere is a crucial component of the Earth's climate system, and comprises sea ice, snow, glaciers, ice cap, ice shelves, river and lake ice, ice sheets and frozen ground. The cryosphere has shown ice growth and decay on many timescales associated both with 100,000 year ice age cycles and with shorter-term (Ice Age. Crucially the cyosphere acts as a barometer for climate change because it provides a visible means of assessing the impacts of recent climate warming. Coastal Arctic regions are particularly sensitive to climate change, and records of glacier fluctuations can be used to infer past climate. The western Svalbard margin is a climatically sensitive region presently influenced by the warm and saline Atlantic water of the West Spitsbergen Current. This current is the northernmost extension of the Norwegian Atlantic Current that transports significant quantities of heat northward, maintaining the seas west of the Svalbard shelf increasingly ice free. For the Svalbard area there are currently a number of low-resolution (centennial to multi-decadal) marine records that span the Holocene. Despite their low resolution, several studies have highlighted abrupt environmental shifts and fluctuating glacial conditions during the Holocene. A few low-resolution lake records and other sporadic terrestrial datasets also exist providing a limited insight into the terrestrial environmental changes over the last two millennia. We have generated the first sub-decadal resolution late Holocene climatic record, in order to determine the nature and timing of environmental changes across transient climate events at an unprecedented temporal scale for this region. XRF analyses provides the high-resolution data series, which has been integrated with sedimentological data to better define the environmental processes; thus providing the basis for the reconstruction of climate change in this glaciated fjordic environment.

  8. Impacts of using spectral nudging on regional climate model RCA4 simulations of the Arctic

    Directory of Open Access Journals (Sweden)

    P. Berg

    2013-01-01

    Full Text Available The performance of the Rossby Centre regional climate model RCA4 is investigated for the Arctic CORDEX region, with an emphasis on its suitability to be coupled to a regional ocean and sea-ice model. Large biases in mean sea level pressure (MSLP are identified, with pronounced too high pressure centred over the North Pole in summer of over 5 hPa, and too low pressure in winter of a similar magnitude. These lead to biases in the surface winds, which will potentially lead to strong sea-ice biases in a future coupled system. The large scale circulation is believed to be the major reason for the biases, and an implementation of spectral nudging is applied to remedy the problems by constraining the large scale components of the driving fields within the interior domain. It is found that the spectral nudging generally corrects for the MSLP and wind biases, while not significantly affecting other variables such as surface radiative components, two metre temperature and precipitation.

  9. Earth System Modeling and Field Experiments in the Arctic-Boreal Zone - Report from a NASA Workshop

    Science.gov (United States)

    Sellers, Piers; Rienecker Michele; Randall, David; Frolking, Steve

    2012-01-01

    Early climate modeling studies predicted that the Arctic Ocean and surrounding circumpolar land masses would heat up earlier and faster than other parts of the planet as a result of greenhouse gas-induced climate change, augmented by the sea-ice albedo feedback effect. These predictions have been largely borne out by observations over the last thirty years. However, despite constant improvement, global climate models have greater difficulty in reproducing the current climate in the Arctic than elsewhere and the scatter between projections from different climate models is much larger in the Arctic than for other regions. Biogeochemical cycle (BGC) models indicate that the warming in the Arctic-Boreal Zone (ABZ) could lead to widespread thawing of the permafrost, along with massive releases of CO2 and CH4, and large-scale changes in the vegetation cover in the ABZ. However, the uncertainties associated with these BGC model predictions are even larger than those associated with the physical climate system models used to describe climate change. These deficiencies in climate and BGC models reflect, at least in part, an incomplete understanding of the Arctic climate system and can be related to inadequate observational data or analyses of existing data. A workshop was held at NASA/GSFC, May 22-24 2012, to assess the predictive capability of the models, prioritize the critical science questions; and make recommendations regarding new field experiments needed to improve model subcomponents. This presentation will summarize the findings and recommendations of the workshop, including the need for aircraft and flux tower measurements and extension of existing in-situ measurements to improve process modeling of both the physical climate and biogeochemical cycle systems. Studies should be directly linked to remote sensing investigations with a view to scaling up the improved process models to the Earth System Model scale. Data assimilation and observing system simulation

  10. Little auks buffer the impact of current Arctic climate change

    DEFF Research Database (Denmark)

    Grémillet, David; Welcker, Jorg; Karnovsky, Nina J.

    2012-01-01

    Climate models predict a multi-degree warming of the North Atlantic in the 21st century. A research priority is to understand the impact of such changes upon marine organisms. With 40-80 million individuals, planktivorous little auks (Alle alle) are an essential component of pelagic food webs in ...

  11. A regional climate model for the Arctic and the North Atlantic; Ein regionales Klimamodell fuer die Arktis und den Nordatlantik

    Energy Technology Data Exchange (ETDEWEB)

    Berndt, H.

    2001-07-01

    The Arctic and the subpolar region of the North Atlantic with their complex net of mechanisms and feedbacks play an important role in the climate system. Because of the sparse observations and the low resolution of the global models the high-resolution regional climate model REMO provides an improved tool to investigate arctic processes. REMO is based on the former numerical weather prediction model EM of the German Weather Service (DWD) and was further developed at the Max-Planck-Institute for Meteorology (MPIfM) in Hamburg. It has two different parameterization schemes - the original one called DWD-physics and additionally the ECHAM4-physics from MPIfM. The dynamical scheme is in both cases identical. In a first step REMO is adapted to the new domain. This configuration covers the Arctic and the North Atlantic down to 40 N with a horizontal resolution of 0.5 x 0.5 and 121 x 145 grid points. Different periods are simulated with DWD- and ECHAM4-Physics in forecast - as well as in climate-mode. Lateral boundary conditions are taken from NCEP/NCAR-reanalysis. Comparing REMO with ship observations in the Labrador Sea yields a better correspondence than the reanalysis data. Simulated precipitation is overestimated most probably due to unrealistic high humidity in the NCEP/NCAR-reanalysis. Observed sensible heat fluxes are much lower than the REMO and NCEP/NCAR simulated fluxes. REMO simulations in climate- and forecast-mode with ECHAM4-parameterizations are compared with measured surface temperatures and precipitation distributions. While there are numerically generated spectral spikes in the NCEP/NCAR precipitation fields in the Arctic, they are not found in the REMO results. In a sensitivity study the impact of higher surface roughness in the marginal ice zone is investigated. Ensemble experiments show the high internal variability masking any signals due to the changed roughness length. This high internal variability is mostly due to the large model domain and the

  12. International arctic systems for observing the atmosphere

    DEFF Research Database (Denmark)

    Uttal, Taneil; Starkweather, Sandra; Drummond, James R.;

    2016-01-01

    IASOA activities and partnerships were initiated as a part of the 2007-2009 International Polar Year (IPY) and are expected to continue for many decades as a legacy program. The IASOA focus is on coordinating intensive measurements of the Arctic atmosphere collected in the U.S., Canada, Russia, N...

  13. Modeling the Oceanic Exchanges Across the Main Arctic Gateways with Emphasis on Atlantic Water and Its Impact on Sea Ice and Climate

    Science.gov (United States)

    Maslowski, Wieslaw; Osinski, Robert; Clement Kinney, Jaclyn; Roberts, Andrew; DiMaggio, Dominic; Craig, Anthony

    2016-04-01

    Estimation of the oceanic budgets of total mass and property exchanges across the main Arctic gateways is challenging from both observational and modeling points of view. While data are insufficient to close such budgets, ocean models commonly struggle with representing transports through the narrow and shallow gates (i.e. Bering Strait and the Canadian Arctic Archipelago) as well as exchanges across Fram Strait or the Barents Sea. Uncertainties in observational constraints at those gates are part of the modeling problems. Yet, realistic model representation of oceanic fluxes, including those associated with Atlantic water, is critical to understanding, simulation and prediction of their impact on the sea ice cover and related feedbacks to the atmosphere and climate. We analyze results from several multi-decadal simulations of the Regional Arctic System Model (RASM) focusing on oceanic fluxes across the Arctic gateways. RASM is a limited-area, process-resolving, coupled atmosphere - ice - ocean - land model that includes the ocean and sea ice models, which are regionally configured versions of those used in the Community Earth System Model (CESM): the Los Alamos Community Ice Model (CICE) and Parallel Ocean Program (POP). The Weather Research and Forecasting (WRF) is used for an atmospheric model, with land surface processes and hydrology represented by the Variable Infiltration Capacity (VIC) model. RASM's pan-Arctic domain covers the entire Northern Hemisphere marine cryosphere, terrestrial drainage and, major inflow/outflow channels to/from the Arctic Ocean, with large portions of the subpolar oceans to allow optimal simulation of the oceanic pathways into and from the central Arctic. The ocean model uses 45 vertical z-coordinate levels and 1/12° or 1/48° rotated sphere meshes with an equator extending across the North Pole, resulting in ~9.3km or 2.4km resolution in the Arctic Ocean, and minimal area distortion near the boundaries. The main objective of this

  14. The Svalbard REU Program: Undergraduates Pursuing Arctic Climate Change Research on Svalbard, Norway

    Science.gov (United States)

    Roof, S.; Werner, A.

    2007-12-01

    The Svalbard Research Experiences for Undergraduates (REU) program sponsored by the Arctic Natural Sciences Program of the National Science Foundation has been successfully providing international field research experiences since 2004. Each year, 7-9 undergraduate students have participated in 4-5 weeks of glacial geology and climate change fieldwork on Spitsbergen in the Svalbard archipelago in the North Atlantic (76- 80° N lat.). While we continue to learn new and better ways to run our program, we have learned specific management and pedagogical strategies that allow us to streamline our logistics and to provide genuine, meaningful research opportunities to undergraduate students. We select student participants after extensive nationwide advertising and recruiting. Even before applying to the program, students understand that they will be doing meaningful climate change science, will take charge of their own project, and will be expected to continue their research at their home institution. We look for a strong commitment of support from a student's advisor at their home institution before accepting students into our program. We present clear information, including participant responsibilities, potential risks and hazards, application procedures, equipment needed, etc on our program website. The website also provides relevant research papers and data and results from previous years, so potential participants can see how their efforts will contribute to growing body of knowledge. New participants meet with the previous years' participants at a professional meeting (our "REUnion") before they start their field experience. During fieldwork, students are expected to develop research questions and test their own hypotheses while providing and responding to peer feedback. Professional assessment by an independent expert provides us with feedback that helps us improve logistical procedures and shape our educational strategies. The assessment also shows us how

  15. Change of sea ice content in the Arctic and the associated climatic effects: detection and simulation

    Directory of Open Access Journals (Sweden)

    I. I. Mokhov

    2013-01-01

    Full Text Available Modeling results of the impact of sea surface temperature and sea ice extent changes over the last decades on the formation of weather and climate anomalies are presented. It was found that the Arctic sea ice area reduction may lead to anti-cyclonic regimes’ formation causing anomalously cold winters in particular on the Russian territory. Using simulation with an atmospheric general circulation model, it is shown that the Early 20th Century Warming must have been accompanied by a large negative Arctic sea ice area anomaly in winter time. The results imply a considerable role of long-term natural climate variations in the modern sea ice area decrease. Estimates of the possible probability’s changes of the dangerous events of strong winds and high waves in the Arctic basin and favorable navigation conditions for the Northern Sea Route in the 21st century are made based on numerical model calculations. An increase of extreme wave height is found to the middle of the 21st century for Kara and Chukchi Seas as a consequence of prolonged run length and increased surface winds.

  16. Proceedings of the 2005 conference on assessment and remediation of contaminated sites in Arctic and cold climates

    Energy Technology Data Exchange (ETDEWEB)

    Biggar, K.; Cotta, G.; Mullick, A.; Nahir, M.; Buchko, J.; Ho, A.; Guigard, S.; Goulden, W. (eds.)

    2005-07-01

    With increasing activity and interest in the diamond mines and oil and gas industry in Canada's Arctic along with increased activity in the Antarctic, Alaska and Russia, the exchange of knowledge concerning development in the Arctic and other cold climates has become increasing relevant. The presentations at this conference focused on the assessment and remediation of contaminated sites in colder climates and regions around the world. Issues concerning Aboriginal involvement in impact management and collaborative planning were reviewed. The development of risk assessment methodologies and new remediation approaches and techniques were examined, as well as new closure and decommissioning management strategies. Issues concerning landfills, water migration, engineering and geologic considerations and barrier systems were reviewed. Other topics of discussion included the development of site-specific environmental criteria, issues concerning the remediation of mines, new developments in soil remediation, hydrocarbon, chlorinated ethenes and soil nitrogen ratios. Key challenges include the effects of cold temperatures on maintenance and remedial effectiveness, as well as the accumulation of hydrocarbons in the soil at low temperatures. Remediation planning and logistical support issues were also discussed. A total of 42 papers were presented at this conference, of which 10 have been indexed separately for inclusion in this database. refs., tabs., figs.

  17. Climate change and infectious diseases in the Arctic: establishment of a circumpolar working group

    Directory of Open Access Journals (Sweden)

    Alan J. Parkinson

    2014-09-01

    Full Text Available The Arctic, even more so than other parts of the world, has warmed substantially over the past few decades. Temperature and humidity influence the rate of development, survival and reproduction of pathogens and thus the incidence and prevalence of many infectious diseases. Higher temperatures may also allow infected host species to survive winters in larger numbers, increase the population size and expand their habitat range. The impact of these changes on human disease in the Arctic has not been fully evaluated. There is concern that climate change may shift the geographic and temporal distribution of a range of infectious diseases. Many infectious diseases are climate sensitive, where their emergence in a region is dependent on climate-related ecological changes. Most are zoonotic diseases, and can be spread between humans and animals by arthropod vectors, water, soil, wild or domestic animals. Potentially climate-sensitive zoonotic pathogens of circumpolar concern include Brucella spp., Toxoplasma gondii, Trichinella spp., Clostridium botulinum, Francisella tularensis, Borrelia burgdorferi, Bacillus anthracis, Echinococcus spp., Leptospira spp., Giardia spp., Cryptosporida spp., Coxiella burnetti, rabies virus, West Nile virus, Hantaviruses, and tick-borne encephalitis viruses.

  18. Dependence of Arctic climate on the latitudinal position of stationary waves and to high-latitudes surface warming

    Science.gov (United States)

    Shin, Yechul; Kang, Sarah M.; Watanabe, Masahiro

    2017-02-01

    Previous studies suggest large uncertainties in the stationary wave response under global warming. Here, we investigate how the Arctic climate responds to changes in the latitudinal position of stationary waves, and to high-latitudes surface warming that mimics the effect of Arctic sea ice loss under global warming. To generate stationary waves in an atmospheric model coupled to slab ocean, a series of experiments is performed where the thermal forcing with a zonal wavenumber-2 (with zero zonal-mean) is prescribed at the surface at different latitude bands in the Northern Hemisphere. When the stationary waves are generated in the subtropics, the cooling response dominates over the warming response in the lower troposphere due to cloud radiative effects. Then, the low-level baroclinicity is reduced in the subtropics, which gives rise to a poleward shift of the eddy driven jet, thereby inducing substantial cooling in the northern high latitudes. As the stationary waves are progressively generated at higher latitudes, the zonal-mean climate state gradually becomes more similar to the integration with no stationary waves. These differences in the mean climate affect the Arctic climate response to high-latitudes surface warming. Additional surface heating over the Arctic is imposed to the reference climates in which the stationary waves are located at different latitude bands. When the stationary waves are positioned at lower latitudes, the eddy driven jet is located at higher latitude, closer to the prescribed Arctic heating. As baroclinicity is more effectively perturbed, the jet shifts more equatorward that accompanies a larger reduction in the poleward eddy transport of heat and momentum. A stronger eddy-induced descending motion creates greater warming over the Arctic. Our study calls for a more accurate simulation of the present-day stationary wave pattern to enhance the predictability of the Arctic warming response in a changing climate.

  19. Globalization and climate change challenges the Arctic communities adaptability and increases vulnerability

    DEFF Research Database (Denmark)

    Hendriksen, Kåre

    2011-01-01

    countries, carrying out the processing before export, are increasing. Although the local populations often are able to adapt to climate change and exploit new seasonal fluxions and species, these developments leaves a series of smaller settlements without proper basis for commercially viable activities...... pressure from multinational companies to exploit the Arctic mineral and oil resources as well as hydro-power in large scale industries appears to (local) governments as a potential for economic growth and thus reduced economic dependence on subsidies from the nation states the Arctic are dependent of...... in contemporary developments leaving them with a feeling of being powerless. The consequences of contemporary policies and the problems arising will be illustrated through examples from traditional hunting and fishing districts in Greenland....

  20. Climate Change Influences on Species Interrelationships and Distributions in High-Arctic Greenland

    DEFF Research Database (Denmark)

    D. R., Klein; Bruun, H. H.; Lundgren, R.

    2008-01-01

    , reproduction, and dispersal of all life forms present. Climate-associated changes in the biotic communities of the region are altering inter-species interactions, notably pollination, seed dispersal and plant-herbivore relations. Sexual reproduction and dispersal of propagules, primarily seeds, are essential...... be of particular significance to long-distance seed dispersal. In Northeast Greenland, dispersal of viable seeds may frequently occur by passage through the guts of geese and musk oxen. Research at Zackenberg on the role of insects in pollination of flowering plants has shown that Diptera species, primarily flies......, dominate among the insect species visiting flowers each summer. Diptera, Lepidoptera (butterflies and moths), Hymenoptera (bumble bees and small wasps), and one Hemiptera (true bugs) species have constituted the primary pollinators at Zackenberg. Arctic willow Salix arctica, white arctic bell heather...

  1. The Blazing Arctic? Linkages of Tundra Fire Regimes to Climatic Change and Implications for Carbon Cycling (Invited)

    Science.gov (United States)

    Hu, F.; Higuera, P. E.; Walsh, J. E.; Chapman, W.; Duffy, P.; Brubaker, L.; Chipman, M. L.

    2010-12-01

    Among the major challenges in anticipating Arctic changes are “surprises” stemming from changes in system components that have remained relatively stable in the historic record. Tundra burning is potentially one such component. We conducted charcoal analysis of lake sediments from several tundra regions to evaluate the uniqueness of recent tundra fires, and examined potential climatic controls of Alaskan tundra fires from CE 1950-2009. A striking example of tundra burning is the 2007 Anaktuvuk River (AR) Fire, an unusually large fire in the tundra of the Alaskan Arctic. This fire doubled the area burned north of 68 oN in that region since record keeping began in 1950. Analysis of lake-sediment cores reveals peak values of charcoal accumulation corresponding to the AR Fire in 2007, with no evidence of other fire events in that area throughout the past five millennia. However, a number of tundra fires, including one as large as the AR Fire, have occurred over the past 60 years in western Alaska, where average summer temperatures are substantially higher than the AR area. In addition, charcoal analysis of lake sediments from interior and northwestern Alaska suggests that during certain periods of the Late Glacial and Holocene, tundra fire frequencies were as high as those of the modern boreal forests. These records along with the AR and historic fires demonstrate that tundra ecosystems support diverse fire regimes and can burn frequently. Reconciling these dramatic differences in tundra fire regimes requires knowledge of climate-fire relationships. Atmospheric reanalysis suggests that the AR Fire was favored by exceptionally warm/dry weather conditions in summer and early autumn. Boosted regression tree modeling shows that warm, dry summer conditions can explain up to 95% of the inter-annual variability in tundra area burned throughout Alaska over the past 60 years and that the response of tundra burning to climatic warming is non-linear. Additionally, tundra area

  2. Arctic Ocean

    Science.gov (United States)

    Parkinson, Claire L.; Zukor, Dorothy J. (Technical Monitor)

    2000-01-01

    The Arctic Ocean is the smallest of the Earth's four major oceans, covering 14x10(exp 6) sq km located entirely within the Arctic Circle (66 deg 33 min N). It is a major player in the climate of the north polar region and has a variable sea ice cover that tends to increase its sensitivity to climate change. Its temperature, salinity, and ice cover have all undergone changes in the past several decades, although it is uncertain whether these predominantly reflect long-term trends, oscillations within the system, or natural variability. Major changes include a warming and expansion of the Atlantic layer, at depths of 200-900 m, a warming of the upper ocean in the Beaufort Sea, a considerable thinning (perhaps as high as 40%) of the sea ice cover, a lesser and uneven retreat of the ice cover (averaging approximately 3% per decade), and a mixed pattern of salinity increases and decreases.

  3. Contrasted climatic trends in the Atlantic vs. Pacific gateways of the Arctic Ocean during the Holocene

    Science.gov (United States)

    de Vernal, A.; Hillaire-Marcel, C.; Rochon, A.

    2013-12-01

    The reconstruction of sea-surface conditions including sea ice cover was undertaken based on about 20 marine sediment cores collected in the Arctic Ocean and subarctic seas. The approach has been standardized and mostly relies on the modern analogue technique applied to dinoflagellate cyst assemblages, which permit simultaneous estimates of sea ice cover, summer sea-surface temperature and salinity. The results show some regionalism in both trends, amplitude and overall variability. In general, changes of small amplitude are recorded in the Canadian Arctic whereas a slight cooling trend with an increasing sea ice cover characterizes the Northern Baffin Bay and Fram Strait areas from mid to late Holocene. In contrast, the Chukchi Sea records show large amplitude variations with millennial pacing making difficult to define any trend. The Chukchi Sea data indicate reduced sea ice and warmer conditions during the mid-Holocene, notably around 6.5 and 3.5 ka, and also point to important variations during the last millennium. The overall results suggest a higher variability thus sensitivity to climate change, in the Chukchi Sea area than in the Eastern parts of the Arctic and subarctic regions, which are largely influenced by northern branches of the North Atlantic Drift. The climate sensitivity of the Chukchi Sea area may be related to the proximity of the Pacific gateway. Strong linkages between sea-surface conditions, sea ice cover and export rate seem tightly linked there with large scale atmospheric synopses in the North Pacific and possibly the tropical Pacific. The apparent consistency of the Mount Logan record (Fisher et al., the Holocene 2008) with those of the Chukchi Sea (de Vernal et al., Quat. Sci. Rev. 2013) tends to support the hypothesis of a strong influence of North Pacific atmospheric teleconnections on sea-surface conditions in the Western Arctic.

  4. Evaluating climate variables, indexes and thresholds governing Arctic urban sustainability: case study of Russian permafrost regions

    Science.gov (United States)

    Anisimov, O. A.; Kokorev, V.

    2013-12-01

    Addressing Arctic urban sustainability today forces planners to deal with the complex interplay of multiple factors, including governance and economic development, demography and migration, environmental changes and land use, changes in the ecosystems and their services, and climate change. While the latter can be seen as a factor that exacerbates the existing vulnerabilities to other stressors, changes in temperature, precipitation, snow, river and lake ice, and the hydrological regime also have direct implications for the cities in the North. Climate change leads to reduced demand for heating energy, on one hand, and heightened concerns about the fate of the infrastructure built upon thawing permafrost, on the other. Changes in snowfall are particularly important and have direct implications for the urban economy, as together with heating costs, expenses for snow removal from streets, airport runways, roofs and ventilation corridors underneath buildings erected on pile foundations on permafrost constitute the bulk of the city's maintenance budget. Many cities are located in river valleys and are prone to flooding that leads to enormous economic losses and casualties, including human deaths. The severity of the northern climate has direct implications for demographic changes governed by regional migration and labor flows. Climate could thus be viewed as an inexhaustible public resource that creates opportunities for sustainable urban development. Long-term trends show that climate as a resource is becoming more readily available in the Russian North, notwithstanding the general perception that globally climate change is one of the challenges facing humanity in the 21st century. In this study we explore the sustainability of the Arctic urban environment under changing climatic conditions. We identify key governing variables and indexes and study the thresholds beyond which changes in the governing climatic parameters have significant impact on the economy

  5. US Navy Operational Global Ocean and Arctic Ice Prediction Systems

    Science.gov (United States)

    2014-09-01

    Arctic ice prediction systems. Oceanography 27(3):32–43, http://dx.doi.org/10.5670/oceanog.2014.66. DOI http://dx.doi.org/10.5670/oceanog.2014.66...P E C I A L I S S U E O N N AV Y O P E R AT I O N A L M O D E L S US Navy Operational Global Ocean and Arctic Ice Prediction Systems B Y E...and forecasting of oceanic “ weather ,” including three dimensional (3D) ocean temperature, salinity, and current structure; surface mixed layer

  6. Assessing the Global and Arctic Transport of Polychlorinated Biphenyls Under Present and Future Climate and Emissions

    Science.gov (United States)

    Friedman, C. L.; Selin, N. E.

    2014-12-01

    We simulate the present and potential future atmospheric transport and fate of polychlorinated biphenyls (PCBs), using the global chemical transport model GEOS-Chem. PCBs are toxic, persistent, and bioaccumulative chemicals whose production and use have been banned internationally. PCBs continue to cycle through the global atmosphere, however, because of their persistence, passive emissions from remaining stocks, and release from natural storage reservoirs such as oceans or soils. In particular, PCBs have been shown to transport long distances in the atmosphere to locations remote from emissions, such as the Arctic, where they can accumulate in wildlife and humans, putting health at risk. Previous studies have suggested that PCBs may be remobilized in a changing climate because higher temperatures will cause greater re-emissions from surface reservoirs. Here, we modify GEOS-Chem to simulate atmospheric PCB transport and investigate the relative effects of predicted climate changes and projected declines in primary emissions, especially on transport to the Arctic. We quantify changes in atmospheric concentrations of two PCBs (CB28 and CB 153) under 2050 climate ("FC"); 2050 emissions ("FE"); and 2050 climate and emissions combined ("FCFE"); relative to a 2000 climate, 2000 emissions control scenario, and determine the major processes affecting these changes. In the version of the model presented here, only soil-atmosphere surface interactions are considered, though future versions will include interaction with other surface media. Our results suggest projected 2050 emissions will play a stronger role than 2050 climate in controlling PCB concentrations of different volatilities. Temperature increases under FC cause increases in emissions of only 4% at most, resulting in negligible concentration changes relative to the FE scenario, in which primary emissions are projected to decline to <0.05% of present-day. Thus, the concentrations in the combined FCFE scenario are

  7. The Arctic Summer Cloud Ocean Study (ASCOS) : Overview and experimental design

    NARCIS (Netherlands)

    Tjernström, M.; Leck, C.; Birch, C.E.; Bottenheim, J.W.; Brooks, B.J.; Brooks, I.M.; Bäcklin, L.; Chang, R.Y.W.; Leeuw, G. de; Liberto, L. di; Rosa, S. de la; Granath, E.; Graus, M.; Hansel, A.; Heintzenberg, J.; Held, A.; Hind, A.; Johnston, P.; Knulst, J.; Martin, M.; Matrai, P.A.; Mauritsen, T.; Müller, M.; Norris, S.J.; Orellana, M.V.; Orsini, D.A.; Paatero, J.; Persson, P.O.G.; Gao, Q.; Rauschenberg, C.; Ristovski, Z.; Sedlar, J.; Shupe, M.D.; Sierau, B.; Sirevaag, A.; Sjogren, S.; Stetzer, O.; Swietlicki, E.; Szczodrak, M.; Vaattovaara, P.; Wahlberg, N.; Westberg, M.; Wheeler, C.R.

    2014-01-01

    The climate in the Arctic is changing faster than anywhere else on earth. Poorly understood feedback processes relating to Arctic clouds and aerosol-cloud interactions contribute to a poor understanding of the present changes in the Arctic climate system, and also to a large spread in projections of

  8. Has prey availability for Arctic birds advanced with climate change? Hindcasting the abundance of tundra Arthropods using weather and seasonal variation

    NARCIS (Netherlands)

    Tulp, I.Y.M.; Schekkerman, H.

    2008-01-01

    Of all climatic zones on earth, Arctic areas have experienced the greatest climate change in recent decades. Predicted changes, including a continuing rise in temperature and precipitation and a reduction in snow cover, are expected to have a large impact on Arctic life. Large numbers of birds breed

  9. Has prey availability for Arctic birds advanced with climate change? Hindcasting the abundance of tundra arthropods using weather and seasonal variations

    NARCIS (Netherlands)

    Tulp, I.; Schekkerman, H.

    2008-01-01

    Of all climatic zones on earth, Arctic areas have experienced the greatest climate change in recent decades. Predicted changes, including a continuing rise in temperature and precipitation and a reduction in snow cover, are expected to have a large impact on Arctic life. Large numbers of birds breed

  10. Enabling Use of Unmanned Aircraft Systems for Arctic Environmental Monitoring

    DEFF Research Database (Denmark)

    Storvold, Rune; la Cour-Harbo, Anders; Mulac, Brenda;

    , satellites and manned aircraft are the traditional platforms on which scientists gather data of the atmosphere, sea ice, glaciers, fauna and vegetation. However, significant data gaps still exist over much of the Arctic because there are few research stations, satellites are often hindered by cloud cover......, poor resolution, and the complicated surface of snow and ice. Measurements made from manned aircraft are also limited because of range and endurance, as well as the danger and costs presented by operating manned aircraft in harsh and remote environments like the Arctic. Unmanned aircraft systems (UAS...

  11. The impact of Arctic sea ice on the Arctic energy budget and on the climate of the Northern mid-latitudes

    Energy Technology Data Exchange (ETDEWEB)

    Semmler, Tido [Alfred Wegener Institute for Polar and Marine Research, Bremerhaven (Germany); Met Eireann, Glasnevin Hill, Dublin 9 (Ireland); McGrath, Ray [Met Eireann, Glasnevin Hill, Dublin 9 (Ireland); Wang, Shiyu [Swedish Meteorological and Hydrological Institute, Norrkoeping (Sweden); Met Eireann, Glasnevin Hill, Dublin 9 (Ireland)

    2012-12-15

    The atmospheric general circulation model EC-EARTH-IFS has been applied to investigate the influence of both a reduced and a removed Arctic sea ice cover on the Arctic energy budget and on the climate of the Northern mid-latitudes. Three 40-year simulations driven by original and modified ERA-40 sea surface temperatures and sea ice concentrations have been performed at T255L62 resolution, corresponding to 79 km horizontal resolution. Simulated changes between sensitivity and reference experiments are most pronounced over the Arctic itself where the reduced or removed sea ice leads to strongly increased upward heat and longwave radiation fluxes and precipitation in winter. In summer, the most pronounced change is the stronger absorption of shortwave radiation which is enhanced by optically thinner clouds. Averaged over the year and over the area north of 70 N, the negative energy imbalance at the top of the atmosphere decreases by about 10 W/m{sup 2} in both sensitivity experiments. The energy transport across 70 N is reduced. Changes are not restricted to the Arctic. Less extreme cold events and less precipitation are simulated in sub-Arctic and Northern mid-latitude regions in winter. (orig.)

  12. A Boolean delay equation model of an interdecadal Arctic climate cycle

    Energy Technology Data Exchange (ETDEWEB)

    Darby, M.S. [Univ. of Exeter (United Kingdom); Mysak, L.A. [McGill Univ., Montreal, Quebec (Canada)

    1993-05-01

    A Boolean delay equation (BDE) model is presented for the interdecadal Arctic and Greenland Sea climate cycle recently proposed by Mysak, Manak and Marsden. It is shown that 15- to 20-year oscillations can occur in the model for a variety of time delays in the BDEs. However, both the period and structure of the oscillations are sensitive to the initial conditions. In an extended model, in which the convection in the Greenland Sea is dependent upon the ice conditions during each of several previous years as well as the current year, the solution structure is more realistic, with two jumps per period of oscillation. 12 refs., 6 figs., 2 tabs.

  13. Climate change and the loss of organic archaeological deposits in the Arctic

    DEFF Research Database (Denmark)

    Hollesen, Jørgen; Matthiesen, Henning; Møller, Anders Bjørn;

    2016-01-01

    The Arctic is warming twice as fast as the global average with overlooked consequences for the preservation of the rich cultural and environmental records that have been stored for millennia in archaeological deposits. In this article, we investigate the oxic degradation of different types...... of organic archaeological deposits located in different climatic zones in West and South Greenland. The rate of degradation is investigated based on measurements of O2 consumption, CO2 production and heat production at different temperatures and water contents. Overall, there is good consistency between...

  14. Postglacial sea-level rise and its impact on the circum-arctic Holocene climate evolution

    Science.gov (United States)

    Bauch, Henning; Abramova, Ekaterina; Alenius, Teija; Saarnisto, Matti

    2016-04-01

    The global sea-level rise after the last glaciation not only affected the surface properties (circulation, T-S, sea ice seasonality) of the Arctic Ocean and nearby seas it also had a strong impact on the Holocene development of the shallow North Siberian shelf systems and the environmental evolution of the adjacent hinterland areas. In this region sea level reconstructions indicate the postglacial highstand occurred some time in the middle Holocene, between 6 to 5 ka (Klemann et al., 2015). After that time the sedimentary regime of the shelf seas stabilized as noted in a drastic decrease in sedimentation rates observed in all sediment cores taken from middle to outer shelf water depths of the Laptev Sea (Bauch et al. 2001). But, at water depths lower than 30 meters - i.e., in the inner shelf and nearer to the coasts - sedimentation continued at relatively higher rates, presumably due to input of terrigenous material from river runoff as well as coastal erosion. In relation to the latter process, the huge Lena Delta should comprise a region of sediment catchment where aggradation wins over erosion. However, little is known about the detailed history of this delta during the second half of the Holocene. We therefore have investigated three islands within the Lena Delta. All of these are comprised of massive peat of several meters in thickness. Picking discrete specimens of water mosses (Sphagnum) only, we have carefully dated these peat sections. The depth/age relation of the sampled profiles reflect the growth rate of peat, and thus, the islands. It shows that the islands' history above the present-day delta sea level is about 4000 yrs. old. Moreover, a significant change in peat growth is noted after 2500 yrs BP in both, accumulation and composition, and allows the conclusion of a major shift in Arctic environmental conditions since then. Thus, our results add further information also for other coastal studies, as the ongoing degradation of the rather vulnerable

  15. Evaluation of a regional climate model for atmospheric simulation over Arctic river basins

    Institute of Scientific and Technical Information of China (English)

    MA Yan; CHEN Shang; HUA Feng; WEI Helin; D. H. BROMWICH

    2008-01-01

    Evaluation on a regional climate model was made with five-month atmospheric simulations over the Arctic river basins. The simulations were performed with a modified mesoscale model, Polar MM5 coupled to the NCAR Land Surface Model (LSM) to illustrate the skill of the coupled model (Polar MM5+LSM) in simulating atmospheric circulation over the Arctic river basins. Near-surface and upper-air observations were used to verify the simulations. Sensitivity studies between the Polar MM5 and Polar MMS+LSM simulations revealed that the coupled model could improve the forecast skill for surface variables at some sites. In addition, the extended evaluations of the coupled model simulations on the North American Arctic domain during December 15, 2002 to May 15, 2003 were carded out. The time series plots and statistics of the observations and Polar MM5+LSM simulations at six stations for near-surface and vertical profiles at 850 hPa and 500 hPa were analyzed. The model was found capable of reproducing the observed atmospheric behavior in both magnitude and variability, especially for temperature and near-surface wind direction.

  16. Diagnostic sea ice predictability in the pan-Arctic and U.S. Arctic regional seas

    Science.gov (United States)

    Cheng, Wei; Blanchard-Wrigglesworth, Edward; Bitz, Cecilia M.; Ladd, Carol; Stabeno, Phyllis J.

    2016-11-01

    This study assesses sea ice predictability in the pan-Arctic and U.S. Arctic regional (Bering, Chukchi, and Beaufort) seas with a purpose of understanding regional differences from the pan-Arctic perspective and how predictability might change under changing climate. Lagged correlation is derived using existing output from the Community Earth System Model Large Ensemble (CESM-LE), Pan-Arctic Ice-Ocean Modeling and Assimilation System, and NOAA Coupled Forecast System Reanalysis models. While qualitatively similar, quantitative differences exist in Arctic ice area lagged correlation in models with or without data assimilation. On regional scales, modeled ice area lagged correlations are strongly location and season dependent. A robust feature in the CESM-LE is that the pan-Arctic melt-to-freeze season ice area memory intensifies, whereas the freeze-to-melt season memory weakens as climate warms, but there are across-region variations in the sea ice predictability changes with changing climate.

  17. Identifying the main drivers of soil carbon response to climate change in arctic and boreal Alaska.

    Science.gov (United States)

    Genet, H.; McGuire, A. D.; He, Y.; Johnson, K.; Wylie, B. K.; Pastick, N. J.; Zhuang, Q.; Zhu, Z.

    2015-12-01

    Boreal and arctic regions represent the largest reservoir of carbon among terrestrial biomes. Most of this carbon is stored deep in the soil in permafrost where frozen organic matter is protected from decomposition. The vulnerability of soil carbon stocks to a changing climate in high latitudes depends on a number of physical and ecological processes. The importance of these processes in controlling the dynamics of soil carbon stocks vary across regions because of variability in vegetation composition, drainage condition, and permafrost characteristics. To better understand the main drivers of the vulnerability of soil carbon stocks to climate change in Alaska, we ran a process-based ecosystem model, the Terrestrial Ecosystem Model. This model explicitly simulates interactions between the carbon cycle and permafrost dynamics and was coupled with a disturbance model and a model of biogenic methane dynamics to assess historical and projected soil carbon dynamics in Alaska, from 1950 to 2100. The uncertainties related to climate, fire regime and atmospheric CO2projections on soil carbon dynamics were quantified by running simulations using climate projections from 2 global circulation models, 3 fossil fuel emission scenarios and 3 alternative fire management scenarios. During the historical period [1950-2009], soil carbon stocks increased by 4.7 TgC/yr in Alaska. Soil carbon stocks decreased in boreal Alaska due to substantial fire activity in the early 2000's. This loss was offset by carbon accumulation in the arctic. Changes in soil carbon stocks from 2010 to 2099 ranged from 8.9 to 25.6 TgC/yr, depending on the climate projections. Soil carbon accumulation was slower in lowlands than in uplands and slower in the boreal than in the arctic regions because of the negative effect of fire activity on soil carbon stocks. Tundra ecosystems were more vulnerable to carbon loss from fire than forest ecosystems because of a lower productivity. As a result, the increase in

  18. Tourism and Arctic Observation Systems: exploring the relationships

    NARCIS (Netherlands)

    Barre, de la Suzanne; Maher, Patrick; Dawson, Jackie; Hillmer-Pegram, Kevin; Huijbens, Edward; Lamers, M.A.J.; Liggett, D.; Müller, D.; Pashkevich, A.; Stewart, Emma

    2016-01-01

    The Arctic is affected by global environmental change and also by diverse interests from many economic sectors and industries. Over the last decade, various actors have attempted to explore the options for setting up integrated and comprehensive trans-boundary systems for monitoring and observing th

  19. Arctic freshwater synthesis: Introduction

    Science.gov (United States)

    Prowse, T.; Bring, A.; Mârd, J.; Carmack, E.

    2015-11-01

    In response to a joint request from the World Climate Research Program's Climate and Cryosphere Project, the International Arctic Science Committee, and the Arctic Council's Arctic Monitoring and Assessment Program, an updated scientific assessment has been conducted of the Arctic Freshwater System (AFS), entitled the Arctic Freshwater Synthesis (AFSΣ). The major reason for joint request was an increasing concern that changes to the AFS have produced, and could produce even greater, changes to biogeophysical and socioeconomic systems of special importance to northern residents and also produce extra-Arctic climatic effects that will have global consequences. Hence, the key objective of the AFSΣ was to produce an updated, comprehensive, and integrated review of the structure and function of the entire AFS. The AFSΣ was organized around six key thematic areas: atmosphere, oceans, terrestrial hydrology, terrestrial ecology, resources and modeling, and the review of each coauthored by an international group of scientists and published as separate manuscripts in this special issue of Journal of Geophysical Research-Biogeosciences. This AFSΣ—Introduction reviews the motivations for, and foci of, previous studies of the AFS, discusses criteria used to define the domain of the AFS, and details key characteristics of the definition adopted for the AFSΣ.

  20. Climatic and biotic extreme events moderate long-term responses of above- and belowground sub-Arctic heathland communities to climate change.

    Science.gov (United States)

    Bokhorst, Stef; Phoenix, Gareth K; Berg, Matty P; Callaghan, Terry V; Kirby-Lambert, Christopher; Bjerke, Jarle W

    2015-11-01

    Climate change impacts are not uniform across the Arctic region because interacting factors causes large variations in local ecosystem change. Extreme climatic events and population cycles of herbivores occur simultaneously against a background of gradual climate warming trends and can redirect ecosystem change along routes that are difficult to predict. Here, we present the results from sub-Arctic heath vegetation and its belowground micro-arthropod community in response to the two main drivers of vegetation damage in this region: extreme winter warming events and subsequent outbreaks of the defoliating autumnal moth caterpillar (Epirrita autumnata). Evergreen dwarf shrub biomass decreased (30%) following extreme winter warming events and again by moth caterpillar grazing. Deciduous shrubs that were previously exposed to an extreme winter warming event were not affected by the moth caterpillar grazing, while those that were not exposed to warming events (control plots) showed reduced (23%) biomass from grazing. Cryptogam cover increased irrespective of grazing or winter warming events. Micro-arthropods declined (46%) following winter warming but did not respond to changes in plant community. Extreme winter warming and caterpillar grazing suppressed the CO2 fluxes of the ecosystem. Evergreen dwarf shrubs are disadvantaged in a future sub-Arctic with more stochastic climatic and biotic events. Given that summer warming may further benefit deciduous over evergreen shrubs, event and trend climate change may both act against evergreen shrubs and the ecosystem functions they provide. This is of particular concern given that Arctic heath vegetation is typically dominated by evergreen shrubs. Other components of the vegetation showed variable responses to abiotic and biotic events, and their interaction indicates that sub-Arctic vegetation response to multiple pressures is not easy to predict from single-factor responses. Therefore, while biotic and climatic events may

  1. Aquatorialities of the Arctic Region – A Systems Theoretical Analysis of Risks

    Directory of Open Access Journals (Sweden)

    Gorm Harste

    2013-06-01

    Full Text Available In order to describe the Arctic system I propose using a concept functionally equivalent to territoriality, namely aquatoriality. Whether communicating about territoriality or aquatoriality, concepts and delimitations are both contingent to forms of communication systems. I will distinguish between six communications systems that differentiated from each other could become involved in the new deals emerging around the Arctic. Apart of an economic communication code about the Arctic, a legal code, ecological communication codes, and tourist communication codes, I will cope with the military coding of the Arctic. These codes could then appear structurally coupled to a political system that in an organizational way appears in the Arctic Council.

  2. Impact of climate change on zooplankton communities, seabird populations and arctic terrestrial ecosystem—A scenario

    Science.gov (United States)

    Stempniewicz, Lech; Błachowiak-Samołyk, Katarzyna; Węsławski, Jan M.

    2007-11-01

    Many arctic terrestrial ecosystems suffer from a permanent deficiency of nutrients. Marine birds that forage at sea and breed on land can transport organic matter from the sea to land, and thus help to initiate and sustain terrestrial ecosystems. This organic matter initiates the emergence of local tundra communities, increasing primary and secondary production and species diversity. Climate change will influence ocean circulation and the hydrologic regime, which will consequently lead to a restructuring of zooplankton communities between cold arctic waters, with a dominance of large zooplankton species, and Atlantic waters in which small species predominate. The dominance of large zooplankton favours plankton-eating seabirds, such as the little auk ( Alle alle), while the presence of small zooplankton redirects the food chain to plankton-eating fish, up through to fish-eating birds (e.g., guillemots Uria sp.). Thus, in regions where the two water masses compete for dominance, such as in the Barents Sea, plankton-eating birds should dominate the avifauna in cold periods and recess in warmer periods, when fish-eaters should prevail. Therefore under future anthropogenic climate scenarios, there could be serious consequences for the structure and functioning of the terrestrial part of arctic ecosystems, due in part to changes in the arctic marine avifauna. Large colonies of plankton-eating little auks are located on mild mountain slopes, usually a few kilometres from the shore, whereas colonies of fish-eating guillemots are situated on rocky cliffs at the coast. The impact of guillemots on the terrestrial ecosystems is therefore much smaller than for little auks because of the rapid washing-out to sea of the guano deposited on the seabird cliffs. These characteristics of seabird nesting sites dramatically limit the range of occurrence of ornithogenic soils, and the accompanying flora and fauna, to locations where talus-breeding species occur. As a result of climate

  3. How is climate warming altering the carbon cycle of a tundra ecosystem in the Siberian Arctic?

    Science.gov (United States)

    Belelli Marchesini, Luca; (Ko) van Huissteden, Jacobus; van der Molen, Michiel; Parmentier, Frans-Jan W.; Maximov, Trofim; Budishchev, Artem; Gallagher, Angela; (Han) Dolman, Albertus J.

    2015-04-01

    Climate has been warming over the the Arctic region with the strongest anomalies taking place in autumn and winter for the period 2000-2010, particularly in northern Eurasia. The quantification of the impact on climate warming on the degradation of permafrost and the associated potential release to the atmosphere of carbon stocked in the soil under the form of greenhouse gases, thus further increasing the radiative forcing of the atmosphere, is currently a matter of scientific debate. The positive trend in primary productivity in the last decades inferred by vegetation indexes (NDVI) and confirmed by observations on the enhanced growth of shrub vegetation represents indeed a contrasting process that, if prevalent could offset GHG emissions or even strengthen the carbon sink over the Arctic tundra. At the site of Kytalyk, in north-eastern Siberia, net fluxes of CO2 at ecosystem scale (NEE) have been monitored by eddy covariance technique since 2003. While presenting the results of the seasonal (snow free period) and inter-annual variability of NEE, conceived as the interplay between meteorological drivers and ecosystem responses, we test the role of climate as the main source of NEE variability in the last decade using a data oriented statistical approach. The impact of the timing and duration of the snow free period on the seasonal carbon budget is also considered. Finally, by including the results of continuous micrometeorological observations of methane fluxes taken during summer 2012, corroborated with seasonal CH4 budgets from two previous shorter campaigns (2008, 2009), as well as an experimentally determined estimate of dissolved organic carbon (DOC) flux, we provide an assessment of the carbon budget and its stability over time. The examined tundra ecosystem was found to sequester CO2 during the snow free season with relatively small inter-annual variability (-97.9±12.1gC m-2) during the last decade and without any evident trend despite the carbon uptake

  4. Nye Lecture: Snow Crystals, Shrubs, and the Changing Climate of the Arctic

    Science.gov (United States)

    Sturm, M.

    2005-12-01

    At the peak of winter, snow covers more than 45 million km2 of the northern hemisphere. More than 90 percent of this snow will melt before the end of the following summer. In the southern part of this snow-covered area, the seasonal pack is ephemeral, lasting but a few short weeks, but with increasing latitude (or altitude), it lasts much longer. In arctic and alpine locations it can persist for 9 months of the year. In these more extreme locations, the snow is an essential element of the ecosystem, both acting upon, and being acted on, by the biota. For historical reasons, our understanding of snow cover and its interactions has come from two disparate scientific sources: geophysicists working on glaciers and avalanches who were trying to understand snow properties and to develop a physical basis for snow science, and ecologists who were trying to understand the impact of snow on plants, animals, and humans. With the recognition now that snow is both a passive and active agent, we are seeing an increasing number of studies wherein both of these traditional approaches are combined. Geophysicists are learning the Latin names of shrubs while botanist can now identify wind slab. A personal example that illustrates the necessity of this melding process has been our effort to understand the climatic implications of Arctic snow-shrub interactions. We have had to combine traditional snow geophysical studies (i.e., crystal growth, thermal processes, light reflection) with traditional ecological studies (i.e., competition, carbon and nitrogen cycling). Through this process we have discovered that snow-shrub interactions, or more broadly, snow-vegetation interactions, are helping to push the Arctic down a warming trajectory that has global implications. Soil microbes and snow crystals, wind-blown snow and shrubs, are all leading actors in a climate change drama whose outcome is of concern to us all.

  5. Climate change and consequences in the Arctic: perception of climate change by the Nenets people of Vaigach Island

    Directory of Open Access Journals (Sweden)

    Alexander N. Davydov

    2011-11-01

    Full Text Available Arctic climate change is already having a significant impact on the environment, economic activity, and public health. For the northern peoples, traditions and cultural identity are closely related to the natural environment so any change will have consequences for society in several ways.A questionnaire was given to the population on the Vaigach island, the Nenets who rely to a large degree on hunting, fishing and reindeer herding for survival. Semi-structured interviews were also conducted about perception of climate change.Climate change is observed and has already had an impact on daily life according to more than 50% of the respondents. The winter season is now colder and longer and the summer season colder and shorter. A decrease in standard of living was noticeable but few were planning to leave.Climate change has been noticed in the region and it has a negative impact on the standard of living for the Nenets. However, as of yet they do not want to leave as cultural identity is important for their overall well-being.

  6. Competition of NAO regime changes and increasing greenhouse gases and aerosols with respect to Arctic climate projections

    Energy Technology Data Exchange (ETDEWEB)

    Dorn, W.; Dethloff, K.; Rinke, A. [Alfred Wegener Institute for Polar and Marine Research, Telegrafenberg A43, 14473 Potsdam (Germany); Roeckner, E. [Max Planck Institute for Meteorology, Bundesstrasse 55, 20146 Hamburg (Germany)

    2003-11-01

    Regional magnitudes and patterns of Arctic winter climate changes in consequence of regime changes of the North Atlantic Oscillation (NAO) are analyzed using a regional atmospheric climate model. The regional model has been driven with data of positive and negative NAO phases from a control simulation as well as from a time-dependent greenhouse gas and aerosol scenario simulation. Both global model simulations include a quite realistic interannual variability of the NAO with pronounced decadal regime changes and no or rather weak long-term NAO trends. The results indicate that the effects of NAO regime changes on Arctic winter temperatures and precipitation are regionally significant over most of northwestern Eurasia and parts of Greenland. In this regard, mean winter temperature variations of up to 6 K may occur over northern Europe. Precipitation and synoptic variability are also regionally modified by NAO regime changes, but not as significantly as temperatures. However, the climate changes associated with the NAO are in some regions clearly stronger than those attributed to enhanced greenhouse gases and aerosols, indicating that projected global changes of the atmospheric composition and internal circulation changes are competing with each other in their importance for the Arctic climate evolution in the near future. The knowledge of the future NAO trend on decadal and longer time scales appears to be vitally important in terms of a regional assessment of climate scenarios for the Arctic. (orig.)

  7. Building Partnerships and Research Collaborations to Address the Impacts of Arctic Change: The North Atlantic Climate Change Collaboration (NAC3)

    Science.gov (United States)

    Polk, J.; North, L. A.; Strenecky, B.

    2015-12-01

    Changes in Arctic warming influence the various atmospheric and oceanic patterns that drive Caribbean and mid-latitude climate events, including extreme events like drought, tornadoes, and flooding in Kentucky and the surrounding region. Recently, the establishment of the North Atlantic Climate Change Collaboration (NAC3) project at Western Kentucky University (WKU) in partnership with the University of Akureyri (UNAK), Iceland Arctic Cooperation Network (IACN), and Caribbean Community Climate Change Centre (CCCCC) provides a foundation from which to engage students in applied research from the local to global levels and more clearly understand the many tenets of climate change impacts in the Arctic within both a global and local community context. The NAC3 project encompasses many facets, including joint international courses, student internships, economic development, service learning, and applied research. In its first phase, the project has generated myriad outcomes and opportunities for bridging STEM disciplines with other fields to holistically and collaboratively address specific human-environmental issues falling under the broad umbrella of climate change. WKU and UNAK students desire interaction and exposure to other cultures and regions that are threatened by climate change and Iceland presents a unique opportunity to study influences such as oceanic processes, island economies, sustainable harvest of fisheries, and Arctic influences on climate change. The project aims to develop a model to bring partners together to conduct applied research on the complex subject of global environmental change, particularly in the Arctic, while simultaneously focusing on changing how we learn, develop community, and engage internationally to understand the impacts and find solutions.

  8. A Two-dimensional Heat Transfer Model for Atmosphere-land System in the Lake-dominated Alaskan Arctic

    Institute of Scientific and Technical Information of China (English)

    LING Feng; ZHANG Ting-jun

    2002-01-01

    Understanding lake ice growth and its sensitivity to climate change is vital to understand the thermal regime of thaw lake systems and predict their response to climate change. In this paper, a physically-based, two-dimensional, non-steady mathematical model is developed for studying the role of shallow tundra lakes in the Alaskan Arctic. Both the radiation absorption in lake water and the phasechange in permafrost are considerd in the model. The materials the model includes are snow, ice, water, unfrozen and frozen soil (peat, silt,sand and gravel). The basic inputs to the model observed mean daily air temperature and snow depth. The ability of this model to simulate lake ice growth and thickness variation, lake water temperature distribution, the thermal regime of permafrost and talik dynamics beneath lakes, and thawing rate of permafrost below and adjacent to shallow thaw lakes offers the potential to describe the effects of climate change in the Alaskan Arctic.

  9. Climate change and water security with a focus on the Arctic

    Directory of Open Access Journals (Sweden)

    Birgitta Evengard

    2011-10-01

    Full Text Available Water is of fundamental importance for human life; access to water of good quality is of vital concern for mankind. Currently however, the situation is under severe pressure due to several stressors that have a clear impact on access to water. In the Arctic, climate change is having an impact on water availability by melting glaciers, decreasing seasonal rates of precipitation, increasing evapotranspiration, and drying lakes and rivers existing in permafrost grounds. Water quality is also being impacted as manmade pollutants stored in the environment are released, lowland areas are flooded with salty ocean water during storms, turbidity from permafrost-driven thaw and erosion is increased, and the growth or emergence of natural pollutants are increased. By 2030 it is estimated that the world will need to produce 50% more food and energy which means a continuous increase in demand for water. Decisionmakers will have to very clearly include life quality aspects of future generations in the work as impact of ongoing changes will be noticeable, in many cases, in the future. This article will focus on effects of climate-change on water security with an Arctic perspective giving some examples from different countries how arising problems are being addressed.

  10. Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions

    Science.gov (United States)

    Isaksen, Ivar S.A.; Gauss, Michael; Myhre, Gunnar; Walter Anthony, Katey M.; Ruppel, Carolyn

    2011-01-01

    The magnitude and feedbacks of future methane release from the Arctic region are unknown. Despite limited documentation of potential future releases associated with thawing permafrost and degassing methane hydrates, the large potential for future methane releases calls for improved understanding of the interaction of a changing climate with processes in the Arctic and chemical feedbacks in the atmosphere. Here we apply a “state of the art” atmospheric chemistry transport model to show that large emissions of CH4 would likely have an unexpectedly large impact on the chemical composition of the atmosphere and on radiative forcing (RF). The indirect contribution to RF of additional methane emission is particularly important. It is shown that if global methane emissions were to increase by factors of 2.5 and 5.2 above current emissions, the indirect contributions to RF would be about 250% and 400%, respectively, of the RF that can be attributed to directly emitted methane alone. Assuming several hypothetical scenarios of CH4 release associated with permafrost thaw, shallow marine hydrate degassing, and submarine landslides, we find a strong positive feedback on RF through atmospheric chemistry. In particular, the impact of CH4 is enhanced through increase of its lifetime, and of atmospheric abundances of ozone, stratospheric water vapor, and CO2 as a result of atmospheric chemical processes. Despite uncertainties in emission scenarios, our results provide a better understanding of the feedbacks in the atmospheric chemistry that would amplify climate warming.

  11. Climate change and water security with a focus on the Arctic.

    Science.gov (United States)

    Evengard, Birgitta; Berner, Jim; Brubaker, Michael; Mulvad, Gert; Revich, Boris

    2011-01-01

    Water is of fundamental importance for human life; access to water of good quality is of vital concern for mankind. Currently however, the situation is under severe pressure due to several stressors that have a clear impact on access to water. In the Arctic, climate change is having an impact on water availability by melting glaciers, decreasing seasonal rates of precipitation, increasing evapotranspiration, and drying lakes and rivers existing in permafrost grounds. Water quality is also being impacted as manmade pollutants stored in the environment are released, lowland areas are flooded with salty ocean water during storms, turbidity from permafrost-driven thaw and erosion is increased, and the growth or emergence of natural pollutants are increased. By 2030 it is estimated that the world will need to produce 50% more food and energy which means a continuous increase in demand for water. Decisionmakers will have to very clearly include life quality aspects of future generations in the work as impact of ongoing changes will be noticeable, in many cases, in the future. This article will focus on effects of climate-change on water security with an Arctic perspective giving some examples from different countries how arising problems are being addressed.

  12. Sensitivity of Pliocene Arctic climate to orbital forcing, atmospheric CO2 and sea ice albedo parameterisation

    Science.gov (United States)

    Howell, Fergus; Haywood, Alan; Pickering, Steven

    2016-04-01

    General circulation model (GCM) simulations of the mid-Pliocene Warm Period (mPWP, 3.264 to 3.025 Myr ago) do not reproduce the magnitude of Northern Hemisphere high latitude surface air and sea surface temperature (SAT and SST) warming that proxy data indicates. There is also large uncertainty regarding the state of sea ice cover in the mPWP. Evidence for both perennial and seasonal mPWP Arctic sea ice is found in analyses of marine sediments, whilst in a multi-model ensemble of mPWP climate simulations, half of the ensemble simulated ice-free summer Arctic conditions. Given the strong influence that sea ice exerts on high latitude temperatures, a better understanding of the nature of mPWP Arctic sea ice would be highly beneficial in understanding proxy derived estimates of high latitude surface temperature change, and the ability of climate models to reproduce this. In GCM simulations, the mPWP is typically represented with fixed orbital forcing, usually identical to modern, and atmospheric CO2 concentrations of ˜ 400 ppm. However, orbital forcing varied over the ˜ 240,000 years of the mPWP, and it is likely that atmospheric CO2 varied as well. A previous study has suggested that the parameterisation of sea ice albedo in the HadCM3 GCM may not reflect the sea ice albedo for a warmer climate, where seasonal sea ice constitutes a greater proportion of the Arctic sea ice cover. These three factors, in isolation and combined, can greatly influence the simulation of Arctic sea ice cover and the degree of high latitude surface temperature warming. This paper explores the impact of various combinations of potential mPWP orbital forcing, atmospheric CO2 concentrations and minimum sea ice albedo on sea ice extent and high latitude warming. The focus is on the Northern Hemisphere, due to availability of proxy data, and the large data-model discrepancies in this region. Changes in orbital forcings are demonstrated to be sufficient to alter the Arctic sea ice simulated by

  13. Effects of changes in climate on landscape and regional processes, and feedbacks to the climate system.

    Science.gov (United States)

    Callaghan, Terry V; Björn, Lars Olof; Chernov, Yuri; Chapin, Terry; Christensen, Torben R; Huntley, Brian; Ims, Rolf A; Johansson, Margareta; Jolly, Dyanna; Jonasson, Sven; Matveyeva, Nadya; Panikov, Nicolai; Oechel, Walter; Shaver, Gus; Schaphoff, Sibyll; Sitch, Stephen

    2004-11-01

    Biological and physical processes in the Arctic system operate at various temporal and spatial scales to impact large-scale feedbacks and interactions with the earth system. There are four main potential feedback mechanisms between the impacts of climate change on the Arctic and the global climate system: albedo, greenhouse gas emissions or uptake by ecosystems, greenhouse gas emissions from methane hydrates, and increased freshwater fluxes that could affect the thermohaline circulation. All these feedbacks are controlled to some extent by changes in ecosystem distribution and character and particularly by large-scale movement of vegetation zones. Indications from a few, full annual measurements of CO2 fluxes are that currently the source areas exceed sink areas in geographical distribution. The little available information on CH4 sources indicates that emissions at the landscape level are of great importance for the total greenhouse balance of the circumpolar North. Energy and water balances of Arctic landscapes are also important feedback mechanisms in a changing climate. Increasing density and spatial expansion of vegetation will cause a lowering of the albedo and more energy to be absorbed on the ground. This effect is likely to exceed the negative feedback of increased C sequestration in greater primary productivity resulting from the displacements of areas of polar desert by tundra, and areas of tundra by forest. The degradation of permafrost has complex consequences for trace gas dynamics. In areas of discontinuous permafrost, warming, will lead to a complete loss of the permafrost. Depending on local hydrological conditions this may in turn lead to a wetting or drying of the environment with subsequent implications for greenhouse gas fluxes. Overall, the complex interactions between processes contributing to feedbacks, variability over time and space in these processes, and insufficient data have generated considerable uncertainties in estimating the net

  14. Why unprecedented ozone loss in the Arctic in 2011? Is it related to climatic change?

    Directory of Open Access Journals (Sweden)

    J.-P. Pommereau

    2013-01-01

    Full Text Available An unprecedented ozone loss occurred in the Arctic in spring 2011. The details of the event are re-visited from the twice-daily total ozone and NO2 columns measurements of the eight SAOZ/NDACC (Système d'Analyse par Observation Zénitale/Network for Detection of Atmospheric Composition Changes stations in the Arctic. It is shown that the total ozone depletion in the polar vortex reached 38% (approx. 170 DU by the end of March that is larger than the 30% of the previous record in 1996. Asides from the long extension of the cold stratospheric NAT PSC period, the amplitude of the event is shown to be resulting from a record daily total ozone loss rate of 0.7% day���1 after mid-February, never seen before in the Arctic but similar to that observed in the Antarctic over the last 20 yr. This high loss rate is attributed to the absence of NOx in the vortex until the final warming, in contrast to all previous winters where, as shown by the early increase of NO2 diurnal increase, partial renoxification is occurring by import of NOx or HNO3 from the outside after minor warming episodes, leading to partial chlorine deactivation.

    The cause of the absence of renoxification and thus of high loss rate, is attributed to a vortex strength similar to that of the Antarctic but never seen before in the Arctic. The total ozone reduction on 20 March was identical to that of the 2002 Antarctic winter, which ended around 20 September, and a 15-day extension of the cold period would have been enough to reach the mean yearly amplitude of the Antarctic ozone hole. However there is no sign of trend since 1994, neither in PSC volume, early winter denitrification, late vortex renoxification, and vortex strength nor in total ozone loss. The unprecedented large Arctic ozone loss in 2011 appears to resulting from an extreme meteorological event and there is no indication of possible strengthening

  15. Why unprecedented ozone loss in the Arctic in 2011? Is it related to climate change?

    Directory of Open Access Journals (Sweden)

    J.-P. Pommereau

    2013-05-01

    Full Text Available An unprecedented ozone loss occurred in the Arctic in spring 2011. The details of the event are revisited from the twice-daily total ozone and NO2 column measurements of the eight SAOZ/NDACC (Système d'Analyse par Observation Zénithale/Network for Detection of Atmospheric Composition Changes stations in the Arctic. It is shown that the total ozone depletion in the polar vortex reached 38% (approx. 170 DU by the end of March, which is larger than the 30% of the previous record in 1996. Aside from the long extension of the cold stratospheric NAT PSC period, the amplitude of the event is shown to be resulting from a record daily total ozone loss rate of 0.7% d−1 after mid-February, never seen before in the Arctic but similar to that observed in the Antarctic over the last 20 yr. This high loss rate is attributed to the absence of NOx in the vortex until the final warming, in contrast to all previous winters where, as shown by the early increase of NO2 diurnal increase, partial renoxification occurs by import of NOx or HNO3 from the outside after minor warming episodes, leading to partial chlorine deactivation. The cause of the absence of renoxification and thus of high loss rate, is attributed to a vortex strength similar to that of the Antarctic but never seen before in the Arctic. The total ozone reduction on 20 March was identical to that of the 2002 Antarctic winter, which ended around 20 September, and a 15-day extension of the cold period would have been enough to reach the mean yearly amplitude of the Antarctic ozone hole. However there is no sign of trend since 1994, either in PSC (polar stratospheric cloud volume (volume of air cold enough to allow formation of PSCs, early winter denitrification, late vortex renoxification, and vortex strength or in total ozone loss. The unprecedented large Arctic ozone loss in 2011 appears to result from an extreme meteorological event and there is no indication of possible strengthening related to

  16. Relevance of hydro-climatic change projection and monitoring for assessment of water cycle changes in the Arctic.

    Science.gov (United States)

    Bring, Arvid; Destouni, Georgia

    2011-06-01

    Rapid changes to the Arctic hydrological cycle challenge both our process understanding and our ability to find appropriate adaptation strategies. We have investigated the relevance and accuracy development of climate change projections for assessment of water cycle changes in major Arctic drainage basins. Results show relatively good agreement of climate model projections with observed temperature changes, but high model inaccuracy relative to available observation data for precipitation changes. Direct observations further show systematically larger (smaller) runoff than precipitation increases (decreases). This result is partly attributable to uncertainties and systematic bias in precipitation observations, but still indicates that some of the observed increase in Arctic river runoff is due to water storage changes, for example melting permafrost and/or groundwater storage changes, within the drainage basins. Such causes of runoff change affect sea level, in addition to ocean salinity, and inland water resources, ecosystems, and infrastructure. Process-based hydrological modeling and observations, which can resolve changes in evapotranspiration, and groundwater and permafrost storage at and below river basin scales, are needed in order to accurately interpret and translate climate-driven precipitation changes to changes in freshwater cycling and runoff. In contrast to this need, our results show that the density of Arctic runoff monitoring has become increasingly biased and less relevant by decreasing most and being lowest in river basins with the largest expected climatic changes.

  17. Climate adaptation is not enough: warming does not facilitate success of southern tundra plant populations in the high Arctic.

    Science.gov (United States)

    Bjorkman, Anne D; Vellend, Mark; Frei, Esther R; Henry, Gregory H R

    2017-04-01

    Rapidly rising temperatures are expected to cause latitudinal and elevational range shifts as species track their optimal climate north and upward. However, a lack of adaptation to environmental conditions other than climate - for example photoperiod, biotic interactions, or edaphic conditions - might limit the success of immigrants in a new location despite hospitable climatic conditions. Here, we present one of the first direct experimental tests of the hypothesis that warmer temperatures at northern latitudes will confer a fitness advantage to southern immigrants relative to native populations. As rates of warming in the Arctic are more than double the global average, understanding the impacts of warming in Arctic ecosystems is especially urgent. We established experimentally warmed and nonwarmed common garden plots at Alexandra Fiord, Ellesmere Island in the Canadian High Arctic with seeds of two forb species (Oxyria digyna and Papaver radicatum) originating from three to five populations at different latitudes across the Arctic. We found that plants from the local populations generally had higher survival and obtained a greater maximum size than foreign individuals, regardless of warming treatment. Phenological traits varied with latitude of the source population, such that southern populations demonstrated substantially delayed leaf-out and senescence relative to northern populations. Our results suggest that environmental conditions other than temperature may influence the ability of foreign populations and species to establish at more northerly latitudes as the climate warms, potentially leading to lags in northward range shifts for some species.

  18. Modeling the evolution of climate-sensitive Arctic subsea permafrost in regions of extensive gas expulsion at the West Yamal shelf

    Science.gov (United States)

    Portnov, Alexey; Mienert, Jurgen; Serov, Pavel

    2014-11-01

    Thawing subsea permafrost controls methane release from the Russian Arctic shelf having a considerable impact on the climate-sensitive Arctic environment. Expulsions of methane from shallow Russian Arctic shelf areas may continue to rise in response to intense degradation of relict subsea permafrost. Here we show modeling of the permafrost evolution from the Late Pleistocene to present time at the West Yamal shelf. Modeling results suggest a highly dynamic permafrost system that directly responds to even minor variations of lower and upper boundary conditions, e.g., geothermal heat flux from below and/or bottom water temperature changes from above permafrost. Scenarios of permafrost evolution show a potentially nearest landward modern extent of the permafrost at the West Yamal shelf limited by ~17 m isobaths, whereas its farthest seaward extent coincides with ~100 m isobaths. The model also predicts seaward tapering of relict permafrost with a maximal thickness of 275-390 m near the shoreline. Previous field observations detected extensive emissions of free gas into the water column at the transition zone between today's shallow water permafrost (20 m). The model adapts well to corresponding heat flux and ocean temperature data, providing crucial information about the modern permafrost conditions. It shows current locations of upper and lower permafrost boundaries and evidences for possible release of methane from the seabed to the hydrosphere in a warming Arctic.

  19. Continuous and discrete extreme climatic events affecting the dynamics of a high-arctic reindeer population.

    Science.gov (United States)

    Chan, Kung-Sik; Mysterud, Atle; Øritsland, Nils Are; Severinsen, Torbjørn; Stenseth, Nils Chr

    2005-10-01

    Climate at northern latitudes are currently changing both with regard to the mean and the temporal variability at any given site, increasing the frequency of extreme events such as cold and warm spells. Here we use a conceptually new modelling approach with two different dynamic terms of the climatic effects on a Svalbard reindeer population (the Brøggerhalvøya population) which underwent an extreme icing event ("locked pastures") with 80% reduction in population size during one winter (1993/94). One term captures the continuous and linear effect depending upon the Arctic Oscillation and another the discrete (rare) "event" process. The introduction of an "event" parameter describing the discrete extreme winter resulted in a more parsimonious model. Such an approach may be useful in strongly age-structured ungulate populations, with young and very old individuals being particularly prone to mortality factors during adverse conditions (resulting in a population structure that differs before and after extreme climatic events). A simulation study demonstrates that our approach is able to properly detect the ecological effects of such extreme climate events.

  20. Modelling impact of climate change on atmospheric transport and fate of persistent organic pollutants in the Arctic

    Directory of Open Access Journals (Sweden)

    K. M. Hansen

    2015-03-01

    Full Text Available The Danish Eulerian Hemispheric Model (DEHM was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs to the Artic and their environmental fate within the Arctic. Two sets of simulations were performed, one with initial environmental concentrations from a 20 year spin-up simulation and one with initial environmental concentrations set to zero. Each set of simulations consisted of two ten-year time slices representing the present (1990–2000 and future (2090–2100 climate conditions. The same POP emissions were applied in all simulations to ensure that the difference in predicted concentrations for each set of simulations only arises from the difference in climate input. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 20% higher across the Northern Hemisphere. The mass of HCHs within the Arctic was predicted to be up to 39% higher, whereas the change in mass of the PCBs was predicted to range from 14% lower to 17% higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depend on the physical-chemical properties of the compounds. Previous model studies have predicted that the effect of

  1. Modelling impact of climate change on atmospheric transport and fate of persistent organic pollutants in the Arctic

    Science.gov (United States)

    Hansen, K. M.; Christensen, J. H.; Geels, C.; Silver, J. D.; Brandt, J.

    2015-03-01

    The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Artic and their environmental fate within the Arctic. Two sets of simulations were performed, one with initial environmental concentrations from a 20 year spin-up simulation and one with initial environmental concentrations set to zero. Each set of simulations consisted of two ten-year time slices representing the present (1990-2000) and future (2090-2100) climate conditions. The same POP emissions were applied in all simulations to ensure that the difference in predicted concentrations for each set of simulations only arises from the difference in climate input. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 20% higher across the Northern Hemisphere. The mass of HCHs within the Arctic was predicted to be up to 39% higher, whereas the change in mass of the PCBs was predicted to range from 14% lower to 17% higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depend on the physical-chemical properties of the compounds. Previous model studies have predicted that the effect of a changed climate on

  2. Early Paleogene Arctic terrestrial ecosystems affected by the change of polar hydrology under global warming:Implications for modern climate change at high latitudes

    Institute of Scientific and Technical Information of China (English)

    Gaytha; A.; LANGLOIS

    2010-01-01

    Our understanding of both the role and impact of Arctic environmental changes under the current global warming climate is rather limited despite efforts of improved monitoring and wider assessment through remote sensing technology. Changes of Arctic ecosystems under early Paleogene warming climate provide an analogue to evaluate long-term responses of Arctic environmental alteration to global warming. This study reviews Arctic terrestrial ecosystems and their transformation under marked change of hydrological conditions during the warmest period in early Cenozoic, the Paleocene and Eocene. We describe a new approach to quantitatively reconstruct high latitudinal paleohydrology using compound-specific hydrogen isotope analysis which applies empirically derived genus-specific hydrogen isotope fractionations to in situ biomolecules from fossil plants. We propose a moisture recycling model at the Arctic to explain the reconstructed hydrogen isotope signals of ancient high latitude precipitation during early Paleogene, which bears implications to the likely change of modern Arctic ecosystems under the projected accelerated global warming.

  3. Sewer Systems and Climate Change

    NARCIS (Netherlands)

    Brandsma, T.

    1993-01-01

    In this article the impact of climate change on the overflows of sewer systems is assessed. The emphasis is on the overflows of combined sewer systems. The purpose is twofold: first, to obtain a first-order estimate of the impact of climate change on overflows of sewer systems; and second, to obtain

  4. 1,500-Year Cycle in Holocene Climate from Burial Lake, Arctic Alaska

    Science.gov (United States)

    Finkenbinder, M. S.; Abbott, M. B.; Dorfman, J. M.; Finney, B.; Stoner, J. S.

    2014-12-01

    Millennial-scale fluctuations in climate conditions are commonly observed in Holocene paleoclimate archives, however the meaning of these variations including whether they might arise from internal or external forcing are still actively debated. Proxy evidence of millennial-scale variability is most clearly present in a few specific parts of the world (e.g. North Atlantic region), whereas a lack of evidence from many other regions may result from a lack of observations or a lack of signal. Here we present the first evidence for such variations in Arctic Alaska using sedimentological and geochemical analyses from Burial Lake (68.43°N, 159.17°W; 460 m above sea level) in the western Brooks Range. We measured biogenic silica (BSi), total organic carbon, total nitrogen, C/N ratios, dry bulk density, magnetic susceptibility and magnetic remanence measurements, and elemental abundances from scanning XRF and use radiocarbon dating on terrestrial macrofossils to establish age control. Large fluctuations in biogenic silica and related proxies at millennial time scales over the last 10,000 cal yr BP are attributed to changes in aquatic productivity, which is indirectly mediated by climate through changes in the duration of the ice-free growing season and the availability of limiting nutrients. Spectral and wavelet analysis of the BSi record indicates a significant 1,500-yr cycle (above 95% confidence) emerges by ~6,000 cal yr BP. Comparison of BSi with reconstructed total solar irradiance reveals a low correlation (r2 = 0.01), suggesting no direct solar forcing of aquatic productivity. A comparison with Northern Hemisphere wide records shows no consistent phase relationship between the timing of maxima/minima in our BSi record. These results are consistent with previous work showing a strong middle Holocene transition into a ~1500-yr cycle. Similar timing for the emergence of an ~1500-yr cycle are found in proxies sensitive to thermohaline circulation and deep water

  5. Projected Impact of Climate Change on the Energy Budget of the Arctic Ocean by a Global Climate Model

    Science.gov (United States)

    Miller, James R.; Russell, Gary L.; Hansen, James E. (Technical Monitor)

    2001-01-01

    The annual energy budget of the Arctic Ocean is characterized by a net heat loss at the air-sea interface that is balanced by oceanic heat transport into the Arctic. The energy loss at the air-sea interface is due to the combined effects of radiative, sensible, and latent heat fluxes. The inflow of heat by the ocean can be divided into two components: the transport of water masses of different temperatures between the Arctic and the Atlantic and Pacific Oceans and the export of sea ice, primarily through Fram Strait. Two 150-year simulations (1950-2099) of a global climate model are used to examine how this balance might change if atmospheric greenhouse gases (GHGs) increase. One is a control simulation for the present climate with constant 1950 atmospheric composition, and the other is a transient experiment with observed GHGs from 1950 to 1990 and 0.5% annual compounded increases of CO2 after 1990. For the present climate the model agrees well with observations of radiative fluxes at the top of the atmosphere, atmospheric advective energy transport into the Arctic, and surface air temperature. It also simulates the seasonal cycle and summer increase of cloud cover and the seasonal cycle of sea-ice cover. In addition, the changes in high-latitude surface air temperature and sea-ice cover in the GHG experiment are consistent with observed changes during the last 40 and 20 years, respectively. Relative to the control, the last 50-year period of the GHG experiment indicates that even though the net annual incident solar radiation at the surface decreases by 4.6 W(per square meters) (because of greater cloud cover and increased cloud optical depth), the absorbed solar radiation increases by 2.8 W(per square meters) (because of less sea ice). Increased cloud cover and warmer air also cause increased downward thermal radiation at the surface so that the net radiation into the ocean increases by 5.0 Wm-2. The annual increase in radiation into the ocean, however, is

  6. Sewer Systems and Climate Change

    OpenAIRE

    Brandsma, T.

    1993-01-01

    In this article the impact of climate change on the overflows of sewer systems is assessed. The emphasis is on the overflows of combined sewer systems. The purpose is twofold: first, to obtain a first-order estimate of the impact of climate change on overflows of sewer systems; and second, to obtain insight into the relevant meteorological variables that are important with respect to climate change. A reservoir model is used to assess the impact of climate change on several combinations of st...

  7. The seasonal foot printing mechanism of spring Arctic sea ice in the Bergen climate models

    Institute of Scientific and Technical Information of China (English)

    GUO Dong; GAO Yongqi; GONG Daoyi

    2014-01-01

    The inlfuence of spring Arctic sea ice variability on the Paciifc Decadal Oscillation (PDO) like sea surface temperature (SST) variability is established and investigated using an Atmosphere Ocean General Circulation Model (AOGCM) of the Bergen Climate Model version 2 (BCM2). The spring Arctic sea ice variability affects the mid-latitudes and tropics through the propagation of the anomalous Eliassen-Palm (E-P) lfux from the polar region to mid- and low-latitudes during boreal spring. The pathway includes anomalous upward wave activity, which propagates to the high troposphere from near the surface of the polar region, turns southward between 500 hPa and 200 hPa and extends downward between 50°N and 70°N, influencing the near surface atmospheric circulation. The alteration of the near surface atmospheric circulation then causes anomalous surface ocean circulation. These circulation changes consequently leads to the SST anomalies in the North Paciifc which may persist until the following summer, named seasonal “foot printing” mechanism (SFPM).

  8. A Large Ornithurine Bird (Tingmiatornis arctica) from the Turonian High Arctic: Climatic and Evolutionary Implications

    Science.gov (United States)

    Bono, Richard K.; Clarke, Julia; Tarduno, John A.; Brinkman, Donald

    2016-12-01

    Bird fossils from Turonian (ca. 90 Ma) sediments of Axel Heiberg Island (High Canadian Arctic) are among the earliest North American records. The morphology of a large well-preserved humerus supports identification of a new volant, possibly diving, ornithurine species (Tingmiatornis arctica). The new bird fossils are part of a freshwater vertebrate fossil assemblage that documents a period of extreme climatic warmth without seasonal ice, with minimum mean annual temperatures of 14 °C. The extreme warmth allowed species expansion and establishment of an ecosystem more easily able to support large birds, especially in fresh water bodies such as those present in the Turonian High Arctic. Review of the high latitude distribution of Northern Hemisphere Mesozoic birds shows only ornithurine birds are known to have occupied these regions. We propose physiological differences in ornithurines such as growth rate may explain their latitudinal distribution especially as temperatures decline later in the Cretaceous. Distribution and physiology merit consideration as factors in their preferential survival of parts of one ornithurine lineage, Aves, through the K/Pg boundary.

  9. The great challenges in Arctic Ocean paleoceanography

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Ruediger, E-mail: Ruediger.Stein@awi.de [Alfred Wegener Institute for Polar and Marine Research, 27568 Bremerhaven (Germany)

    2011-05-15

    Despite the importance of the Arctic in the climate system, the data base we have from this area is still very weak, and large parts of the climate history have not been recovered at all in sedimentary sections. In order to fill this gap in knowledge, international, multidisciplinary expeditions and projects for scientific drilling/coring in the Arctic Ocean are needed. Key areas and approaches for drilling and recovering undisturbed and complete sedimentary sequences are depth transects across the major ocean ridge systems, i.e., the Lomonosov Ridge, the Alpha-Mendeleev Ridge, and the Chukchi Plateau/Northwind Ridge, the Beaufort, Kara and Laptev sea continental margins, as well as the major Arctic gateways towards the Atlantic and Pacific oceans. The new detailed climate records from the Arctic Ocean spanning time intervals from the Late Cretaceous/Paleogene Greenhouse world to the Neogene-Quaternary Icehouse world and representing short- and long-term climate variability on scales from 10 to 10{sup 6} years, will give new insights into our understanding of the Arctic Ocean within the global climate system and provide an opportunity to test the performance of climate models used to predict future climate change. With this, studying the Arctic Ocean is certainly one of the major challenges in climate research for the coming decades.

  10. Numerical simulation of the impact of underlying surface changes on Arctic climate

    Institute of Scientific and Technical Information of China (English)

    LIU Xiying; XIA Huasheng

    2014-01-01

    Using a regional atmospheric model for Arctic climate simulation, two groups of numerical experiments were carried out to study the inlfuence of changes in the underlying surface (land surface, sea surface, and sea ice (LS/SS/SI)) from mild ice years to severe ice years on Arctic climate. In each experiment in the same group, the initial values and lateral boundary conditions were identical. The underlying surface conditions were updated every six hours. The model was integrated for 10 a and monthly mean results were saved for analysis. Variations in annual mean surface air temperature were closely correlated with changes in LS/SS/SI, with a maximum change of more than 15 K. The impact of changes in LS/SS/SI on low-level air temperature was also evident, with signiifcant changes seen over the ocean. However, the maximum change was less than 2 K. For air temperature above 700 hPa, the impact of LS/SS/SI changes was not signiifcant. The distribution of annual mean sea level pressure differences was coincident with the distribution of annual mean sea ice concentration. The difference centers were located in the Barents Sea, the Kara Sea, and the East Siberian Sea, with the maximum value exceeding 3 hPa. For geopotential height, some results passed and some failed at-test. For results passing thet-test, the area of signiifcance did not decrease with height. There was a signiifcant difference at high levels, with a value of 27 gpm in the difference center at 200 hPa.

  11. Climate change and Arctic ecosystems: 2. Modeling, paleodata-model comparisons, and future projections

    Science.gov (United States)

    Kaplan, J.O.; Bigelow, N.H.; Prentice, I.C.; Harrison, S.P.; Bartlein, P.J.; Christensen, T.R.; Cramer, W.; Matveyeva, N.V.; McGuire, A.D.; Murray, D.F.; Razzhivin, V.Y.; Smith, B.; Walker, D. A.; Anderson, P.M.; Andreev, A.A.; Brubaker, L.B.; Edwards, M.E.; Lozhkin, A.V.

    2003-01-01

    Large variations in the composition, structure, and function of Arctic ecosystems are determined by climatic gradients, especially of growing-season warmth, soil moisture, and snow cover. A unified circumpolar classification recognizing five types of tundra was developed. The geographic distributions of vegetation types north of 55??N, including the position of the forest limit and the distributions of the tundra types, could be predicted from climatology using a small set of plant functional types embedded in the biogeochemistry-biogeography model BIOME4. Several palaeoclimate simulations for the last glacial maximum (LGM) and mid-Holocene were used to explore the possibility of simulating past vegetation patterns, which are independently known based on pollen data. The broad outlines of observed changes in vegetation were captured. LGM simulations showed the major reduction of forest, the great extension of graminoid and forb tundra, and the restriction of low- and high-shrub tundra (although not all models produced sufficiently dry conditions to mimic the full observed change). Mid-Holocene simulations reproduced the contrast between northward forest extension in western and central Siberia and stability of the forest limit in Beringia. Projection of the effect of a continued exponential increase in atmospheric CO2 concentration, based on a transient ocean-atmosphere simulation including sulfate aerosol effects, suggests a potential for larger changes in Arctic ecosystems during the 21st century than have occurred between mid-Holocene and present. Simulated physiological effects of the CO2 increase (to > 700 ppm) at high latitudes were slight compared with the effects of the change in climate.

  12. Climate Change, Degradation of Permafrost, and Hazards to Infrastructure in the Circumpolar Arctic.

    Science.gov (United States)

    Anisimov, O.

    2001-12-01

    Warming, thawing and disappearance of permafrost have accelerated in recent decades damaging engineered structures and raising public concerns. By the middle of the 21st century anthropogenic climate change may cause 2 to 3 C warming of the frozen ground, 10% to 16% reduction of the total permafrost area, 30% to 50% deepening of the active-layer thickness, and shifts between the permafrost zones due to cumulative effect of changing surface temperature, soil moisture, and vegetation. Such changes will have important implications for northern engineering and infrastructure built upon permafrost. The foundations supporting engineered structures are designed for the constant climatic conditions with construction-specific safety factor, which in the practice of the cold-region engineering varies typically from 5% to 60% with respect to the bearing capacity. In the zone of discontinuous permafrost a 2.0 C rise in air temperature may decrease the bearing capacity of frozen ground under buildings by more than a half. This may have important consequences for the infrastructure and particularly for residential buildings constructed in the permafrost zone between 1950 and 1990 in northern Russian cities Vorkuta, Yakytsk, Norylsk, and Magadan. Many of them are already weakened or damaged, which may in part be attributed to the effect of climate change. Susceptibility of permafrost to environmental hazards associated with thermokarst, ground settlement, and other destructive cryogenic processes may be crudely evaluated using the geocryological hazard index, which is the combination of the predicted for the future climate relative change in the active-layer thickness and the ground ice content. Predictive maps constructed for scenarios of climate change indicated that several population centers (Barrow, Inuvik), river terminals on the arctic coast of Russia (Salekhard, Igarka, Dudinka, Tiksi), and gas production complexes with associated infrastructure in northwest Siberia fall

  13. Climate change impacts on continental weathering through the Middle Jurassic to Lower Cretaceous of Sverdrup Basin, Canadian Arctic

    Science.gov (United States)

    Galloway, Jennifer; Grasby, Stephen; Swindles, Graeme; Dewing, Keith

    2014-05-01

    Jurassic to Cretaceous strata of Sverdrup Basin, Canadian Arctic Archipelago, contain marine and non-marine successions that can be studied to reconstruct ancient paleoclimates and paleoenvironments that are poorly understood in high-latitude regions. We use element geochemistry integrated with palynology to study a continuous Aalenian to Albian-aged succession preserved in the Hoodoo Dome H-37 oil and gas well located on southern Ellef Ringnes Island near the centre of Sverdrup Basin. Cluster analysis (stratigraphically constrained incremental sum of squares; CONISS) is used to delineate four geochemical zones that are broadly coeval with major changes in palyno-assemblages interpreted to reflect changes in regional paleoclimate. Zone 1 (late Aalenian to Bathonian) is characterized by palynomorphs associated with humid and warm climate conditions. The chemical alteration index (CAI) is high in this interval, expected under this a humid and warm climate. A transition to a seasonally arid and warm climate occurred in the Bathonian and persisted until the Kimmeridgian or Valanginian (Zone 2). This interval is characterized by decreased chemical weathering, indicated by a drop in CAI. The onset of Zone 3 (Kimmeridgian or Valanginian to late Barremian or early Aptian) occurs during a transition to humid and cool climate conditions and is associated with a period of regional uplift and rifting. Zone 3 is marked by a substantial and progressive drop in CAI, indicating a transition from a weathering to transport-dominated system, possibly associated with landscape destabilization. Reduced tectonic activity in Zone 4 (early Aptian to early or mid Albian) shows a return to active chemical weathering, possibly associated with landscape stabilization, suggested by a continued increase in pollen from upland coniferous taxa. The geochemical and palynological records of Middle Jurassic to Lower Cretaceous strata of the Hoodoo Dome H-37 oil and gas well show close correlation

  14. Landscape and Hydrological Transformation in the Canadian High Arctic: Climate Change and Permafrost Degradation As Drivers of Change

    Science.gov (United States)

    Lamoureux, S. F.; Lafreniere, M. J.

    2014-12-01

    Recent climate warming and landscape instability arising from permafrost degradation in the Canadian High Arctic have resulted in significant changes to the hydrological system. We have undertaken an integrated watershed and permafrost research program at the Cape Bounty Arctic Watershed Observatory (75°N, 109°W) in paired watershed-lake systems to assess the impact of these changes. Research has captured hydrological changes resulting from exceptional warmth, and permafrost degradation and disturbance. Results highlight the contrasting effect of thermal (deeper soil thaw) versus physical perturbation (slope failures and permafrost degradation). Thermal perturbation applies to most of the landscape, and results indicate that ground ice melt alters flow and mobilizes solutes for a number of years following a single warm year. These effects are measureable at the slope-catchment scale, especially during baseflow. By contrast, physical disturbance is highly localized and produces high sediment and particulate carbon erosion from slopes, but downstream particulate delivery is dependent on surface connectivity. Recovery from disturbances appears to occur rapidly, and continued geomorphic change and new slope channels result in sustained delivery of particulates to channels. The result is increased long term landscape heterogeneity with respect to erosion compared to the pre-disturbance condition. Downstream channel response to particulate loading further dampens the response to physical disturbance through channel storage of material. Hence, at the larger watershed scale, the effect of physical perturbation is minimal in the initial years of recovery. These results point to a landscape that has been substantially impacted by recent hydrological and permafrost changes. Understanding and distinguishing these impacts provides a basis for systematically evaluating biogeochemical cycling and ecosystem responses in aquatic settings.

  15. Association of climatic factors with infectious diseases in the Arctic and subarctic region – a systematic review

    Directory of Open Access Journals (Sweden)

    Christina Hedlund

    2014-07-01

    Full Text Available Background: The Arctic and subarctic area are likely to be highly affected by climate change, with possible impacts on human health due to effects on food security and infectious diseases. Objectives: To investigate the evidence for an association between climatic factors and infectious diseases, and to identify the most climate-sensitive diseases and vulnerable populations in the Arctic and subarctic region. Methods: A systematic review was conducted. A search was made in PubMed, with the last update in May 2013. Inclusion criteria included human cases of infectious disease as outcome, climate or weather factor as exposure, and Arctic or subarctic areas as study origin. Narrative reviews, case reports, and projection studies were excluded. Abstracts and selected full texts were read and evaluated by two independent readers. A data collection sheet and an adjusted version of the SIGN methodology checklist were used to assess the quality grade of each article. Results: In total, 1953 abstracts were initially found, of which finally 29 articles were included. Almost half of the studies were carried out in Canada (n=14, the rest from Sweden (n=6, Finland (n=4, Norway (n=2, Russia (n=2, and Alaska, US (n=1. Articles were analyzed by disease group: food- and waterborne diseases, vector-borne diseases, airborne viral- and airborne bacterial diseases. Strong evidence was found in our review for an association between climatic factors and food- and waterborne diseases. The scientific evidence for a link between climate and specific vector- and rodent-borne diseases was weak due to that only a few diseases being addressed in more than one publication, although several articles were of very high quality. Air temperature and humidity seem to be important climatic factors to investigate further for viral- and bacterial airborne diseases, but from our results no conclusion about a causal relationship could be drawn. Conclusions: More studies of high quality

  16. Climate change, its consequences in the Arctic and around the world

    Science.gov (United States)

    Jayer, Sophie; Le Divenah, Claudie; Rosetti, Alexandra

    2010-05-01

    CLIMATE CHANGE, ITS CONSEQUENCES IN THE ARCTIC AND AROUND THE WORLD This project has been led in a French European Class either in physics, chemistry, geology, biology and English by: - Sophie Jayer (Biology and geology teacher) - Claudie Le Divenah (Physics and Chemistry teacher) - Alexandra Rosetti (English teacher) As it was a European class, all the classes were held in English. The goals were - to have the students study both sciences and English - to show them that all these subjects were linked in real life and how important English was for scientists - To give them a glimpse of what scientific researches were both in the field and in a lab - To get them involved in the polar year - To make them work on the notion of world citizenship and raise their awareness about the issue of sustainable development We first introduced the Damocles and Tara project to the pupils. Then we studied the Arctic's geography, their inhabitants and ecosystem (Biology and English). In physics and chemistry, they talked about their working conditions, equipments and what kind of analysis they would do. In geology, we studied the evolution of the sea ice and its consequences but also climate changes of the past, the influence of climate on human history and the evidences of global warming nowadays (the pupils had to find information and to make a presentation about different climate events that could be evidence of global warming). A man who works on a research boat for a French national organization came in our class and was able to present his work, the conditions of life on board and to answer the pupils' questions. This is a quick summary of our work. If you need any additional information before the GIFT, please contact me at: sophie.jayer@neuf.fr or Sophie Jayer 61 A route de Paris 78550 Bazainville 0033 (0)1 34 87 61 06 0033 (0)6 20 53 84 65 (mobile) Our group teaches at Emilie de Breteuil High School In Montigny le Bretonneux, 30 km southwest of Paris Lycée Emilie de

  17. A regional climate model for the Arctic and the North Atlantic; Ein regionales Klimamodell fuer die Arktis und den Nordatlantik

    Energy Technology Data Exchange (ETDEWEB)

    Berndt, H.

    2001-07-01

    The Arctic and the subpolar region of the North Atlantic with their complex net of mechanisms and feedbacks play an important role in the climate system. Because of the sparse observations and the low resolution of the global models the high-resolution regional climate model REMO provides an improved tool to investigate arctic processes. REMO is based on the former numerical weather prediction model EM of the German Weather Service (DWD) and was further developed at the Max-Planck-Institute for Meteorology (MPIfM) in Hamburg. It has two different parameterization schemes - the original one called DWD-physics and additionally the ECHAM4-physics from MPIfM. The dynamical scheme is in both cases identical. In a first step REMO is adapted to the new domain. This configuration covers the Arctic and the North Atlantic down to 40 N with a horizontal resolution of 0.5 x 0.5 and 121 x 145 grid points. Different periods are simulated with DWD- and ECHAM4-Physics in forecast - as well as in climate-mode. Lateral boundary conditions are taken from NCEP/NCAR-reanalysis. Comparing REMO with ship observations in the Labrador Sea yields a better correspondence than the reanalysis data. Simulated precipitation is overestimated most probably due to unrealistic high humidity in the NCEP/NCAR-reanalysis. Observed sensible heat fluxes are much lower than the REMO and NCEP/NCAR simulated fluxes. REMO simulations in climate- and forecast-mode with ECHAM4-parameterizations are compared with measured surface temperatures and precipitation distributions. While there are numerically generated spectral spikes in the NCEP/NCAR precipitation fields in the Arctic, they are not found in the REMO results. In a sensitivity study the impact of higher surface roughness in the marginal ice zone is investigated. Ensemble experiments show the high internal variability masking any signals due to the changed roughness length. This high internal variability is mostly due to the large model domain and the

  18. Climate states and variability of Arctic ice and water dynamics during 1946–1997

    OpenAIRE

    Proshutinsky, Andrey Y.; Polyakov, Igor V; Johnson, Mark A.

    1999-01-01

    Recently observed changes in the Arctic have highlighted the need for a better understanding of Arctic dynamics. This research addresses that need and is also motivated by the recent finding of two regimes of Arctic ice - ocean wind-driven circulation. In this paper, we demonstrate that during 1946-1997 the Arctic environmental parameters have oscillated with a period of 10-15 years. Our results reveal significant differences among atmosphere, ice, and ocean processes during the anticyclonic ...

  19. Adapting to Climate Change: Social-Ecological Resilience in a Canadian Western Arctic Community

    Directory of Open Access Journals (Sweden)

    Fikret Berkes

    2002-01-01

    Full Text Available Human adaptation remains an insufficiently studied part of the subject of climate change. This paper examines the questions of adaptation and change in terms of social-ecological resilience using lessons from a place-specific case study. The Inuvialuit people of the small community of Sachs Harbour in Canada's western Arctic have been tracking climate change throughout the 1990s. We analyze the adaptive capacity of this community to deal with climate change. Short-term responses to changes in land-based activities, which are identified as coping mechanisms, are one component of this adaptive capacity. The second component is related to cultural and ecological adaptations of the Inuvialuit for life in a highly variable and uncertain environment; these represent long-term adaptive strategies. These two types of strategies are, in fact, on a continuum in space and time. This study suggests new ways in which theory and practice can be combined by showing how societies may adapt to climate change at multiple scales. Switching species and adjusting the "where, when, and how" of hunting are examples of shorter-term responses. On the other hand, adaptations such as flexibility in seasonal hunting patterns, traditional knowledge that allows the community to diversity hunting activities, networks for sharing food and other resources, and intercommunity trade are longer-term, culturally ingrained mechanisms. Individuals, households, and the community as a whole also provide feedback on their responses to change. Newly developing co-management institutions create additional linkages for feedback across different levels, enhancing the capacity for learning and self-organization of the local inhabitants and making it possible for them to transmit community concerns to regional, national, and international levels.

  20. The impact of a seasonally ice free Arctic Ocean on the climate and surface mass balance of Svalbard

    Directory of Open Access Journals (Sweden)

    J. J. Day

    2011-07-01

    Full Text Available General circulation models (GCMs predict a rapid decrease in Arctic sea ice extent in the 21st century. The decline of September sea ice is expected to continue until the Arctic Ocean is seasonally ice free, leading to a much perturbed Arctic climate with large changes in surface energy flux. Svalbard, located on the present day sea ice edge, contains many low lying ice caps and glaciers which are extremely sensitive to changes in climate. Records of past accumulation indicate that the surface mass balance (SMB of Svalbard is also sensitive to changes in the position of the sea ice edge.

    To investigate the impact of 21st Century sea ice decline on the climate and surface mass balance of Svalbard a high resolution (25 km regional climate model (RCM was forced with a repeating cycle of sea surface temperatures (SSTs and sea ice conditions for the periods 1961–1990 and 2061–2090. By prescribing 20th Century SSTs and 21st Century sea ice for one simulation, the impact of sea ice decline is isolated. This study shows that the coupled impact of sea ice decline and SST increase results in a decrease in SMB, whereas the impact of sea ice decline alone causes an increase in SMB of similar magnitude.

  1. Connecting climate signals with phytoplankton productivity and composition in a high Arctic fjord

    NARCIS (Netherlands)

    van de Poll, Willem

    2016-01-01

    Kongsfjorden is a high Arctic fjord on the West coast of Spitsbergen in a rapidly changing region that experiences both Arctic and sub-Arctic influences. This fjord has been subject to intense research since the 1980s. More recently, an effort was started by the AWI to collect daily physical, chemic

  2. Chemistry and dynamics of the Arctic winter 2015/2016: Simulations with the Chemistry-Climate Model EMAC

    Science.gov (United States)

    Khosrawi, Farahnaz; Kirner, Ole; Sinnhuber, Bjoern-Martin; Ruhnke, Roland; Hoepfner, Michael; Woiwode, Wolfgang; Oelhaf, Hermann; Santee, Michelle L.; Manney, Gloria L.; Froidevaux, Lucien; Murtagh, Donal; Braesicke, Peter

    2016-04-01

    Model simulations of the Arctic winter 2015/2016 were performed with the atmospheric chemistry-climate model ECHAM5/MESSy Atmospheric Chemistry (EMAC) for the POLSTRACC (Polar Stratosphere in a Changing Climate) project. The POLSTRACC project is a HALO mission (High Altitude and LOng Range Research Aircraft) that aims to investigate the structure, composition and evolution of the Arctic Upper Troposphere Lower Stratosphere (UTLS) in a changing climate. Especially, the chemical and physical processes involved in Arctic stratospheric ozone depletion, transport and mixing processes in the UTLS at high latitudes, polar stratospheric clouds as well as cirrus clouds are investigated. The model simulations were performed with a resolution of T42L90, corresponding to a quadratic Gaussian grid of approximately 2.8°× 2.8° degrees in latitude and longitude, and 90 vertical layers from the surface up to 0.01 hPa (approx. 80 km). A Newtonian relaxation technique of the prognostic variables temperature, vorticity, divergence and surface pressure towards ECMWF data was applied above the boundary layer and below 10 hPa, in order to nudge the model dynamics towards the observed meteorology. During the Arctic winter 2015/2016 a stable vortex formed in early December, with a cold pool where temperatures reached below the Nitric Acid Trihydrate (NAT) existence temperature of 195 K, thus allowing Polar Stratospheric Clouds (PSCs) to form. The early winter has been exceptionally cold and satellite observations indicate that sedimenting PSC particles have lead to denitrification as well as dehydration of stratospheric layers. In this presentation an overview of the chemistry and dynamics of the Arctic winter 2015/2016 as simulated with EMAC will be given and comparisons to satellite observations such as e.g. Aura/MLS and Odin/SMR will be shown.

  3. Paradoxical cold conditions during the medieval climate anomaly in the Western Arctic

    Science.gov (United States)

    2016-09-01

    In the Northern Hemisphere, most mountain glaciers experienced their largest extent in the last millennium during the Little Ice Age (1450 to 1850 CE, LIA), a period marked by colder hemispheric temperatures than the Medieval Climate Anomaly (950 to 1250 CE, MCA), a period which coincided with glacier retreat. Here, we present a new moraine chronology based on 36Cl surface exposure dating from Lyngmarksbræen glacier, West Greenland. Consistent with other glaciers in the western Arctic, Lyngmarksbræen glacier experienced several advances during the last millennium, the first one at the end of the MCA, in ~1200 CE, was of similar amplitude to two other advances during the LIA. In the absence of any significant changes in accumulation records from South Greenland ice cores, we attribute this expansion to multi-decadal summer cooling likely driven by volcanic and/or solar forcing, and associated regional sea-ice feedbacks. Such regional multi-decadal cold conditions at the end of the MCA are neither resolved in temperature reconstructions from other parts of the Northern Hemisphere, nor captured in last millennium climate simulations.

  4. Arctic shrubification mediates the impacts of warming climate on changes to tundra vegetation

    Science.gov (United States)

    Mod, Heidi K.; Luoto, Miska

    2016-12-01

    Climate change has been observed to expand distributions of woody plants in many areas of arctic and alpine environments—a phenomenon called shrubification. New spatial arrangements of shrubs cause further changes in vegetation via changing dynamics of biotic interactions. However, the mediating influence of shrubification is rarely acknowledged in predictions of tundra vegetation change. Here, we examine possible warming-induced landscape-level vegetation changes in a high-latitude environment using species distribution modelling (SDM), specifically concentrating on the impacts of shrubification on ambient vegetation. First, we produced estimates of current shrub and tree cover and forecasts of their expansion under climate change scenarios to be incorporated to SDMs of 116 vascular plants. Second, the predictions of vegetation change based on the models including only abiotic predictors and the models including abiotic, shrub and tree predictors were compared in a representative test area. Based on our model predictions, abundance of woody plants will expand, thus decreasing predicted species richness, amplifying species turnover and increasing the local extinction risk for ambient vegetation. However, the spatial variation demonstrated in our predictions highlights that tundra vegetation can be expected to show a wide variety of different responses to the combined effects of warming and shrubification, depending on the original plant species pool and environmental conditions. We conclude that realistic forecasts of the future require acknowledging the role of shrubification in warming-induced tundra vegetation change.

  5. Stable climate and surface mass balance in Svalbard over 1979–2013 despite the Arctic warming

    Directory of Open Access Journals (Sweden)

    C. Lang

    2015-01-01

    (Model for Interdisciplinary Research on Climate global model (MARMIROC5 from the CMIP5 (Coupled Model Intercomparison Project database, we have modelled the climate and surface mass balance of Svalbard at a 10 km resolution over 1979–2013. The integrated total surface mass balance (SMB over Svalbard modelled by MARERA is negative (−1.6 Gt yr−1 with a large interannual variability (7.1 Gt but, unlike over Greenland, there has been no acceleration of the surface melt over the past 35 years because of the recent change in atmospheric circulation bringing northwesterly flows in summer over Svalbard, contrasting the recent observed Arctic warming. However, in 2013, the atmospheric circulation changed to a south–southwesterly flow over Svalbard causing record melt, SMB (−20.4 Gt yr−1 and summer temperature. MIROC5 is significantly colder than ERA-Interim over 1980–2005 but MARMIROC5 is able to improve the near-surface MIROC5 results by simulating not significant SMB differences with MARERA over 1980–2005. On the other hand, MIROC5 does not represent the recent atmospheric circulation shift in summer and induces in MARMIROC5 a significant trend of decreasing SMB (−0.6 Gt yr−2 over 1980–2005.

  6. Paradoxical cold conditions during the medieval climate anomaly in the Western Arctic

    Science.gov (United States)

    Jomelli, Vincent; Lane, Timothy; Favier, Vincent; Masson-Delmotte, Valerie; Swingedouw, Didier; Rinterknecht, Vincent; Schimmelpfennig, Irene; Brunstein, Daniel; Verfaillie, Deborah; Adamson, Kathryn; Leanni, Laëtitia; Mokadem, Fatima; Aumaître, Georges; Bourlès, Didier L.; Keddadouche, Karim

    2016-01-01

    In the Northern Hemisphere, most mountain glaciers experienced their largest extent in the last millennium during the Little Ice Age (1450 to 1850 CE, LIA), a period marked by colder hemispheric temperatures than the Medieval Climate Anomaly (950 to 1250 CE, MCA), a period which coincided with glacier retreat. Here, we present a new moraine chronology based on 36Cl surface exposure dating from Lyngmarksbræen glacier, West Greenland. Consistent with other glaciers in the western Arctic, Lyngmarksbræen glacier experienced several advances during the last millennium, the first one at the end of the MCA, in ~1200 CE, was of similar amplitude to two other advances during the LIA. In the absence of any significant changes in accumulation records from South Greenland ice cores, we attribute this expansion to multi-decadal summer cooling likely driven by volcanic and/or solar forcing, and associated regional sea-ice feedbacks. Such regional multi-decadal cold conditions at the end of the MCA are neither resolved in temperature reconstructions from other parts of the Northern Hemisphere, nor captured in last millennium climate simulations. PMID:27609585

  7. Compositional Stability of the Bacterial Community in a Climate-Sensitive Sub-Arctic Peatland

    Science.gov (United States)

    Weedon, James T.; Kowalchuk, George A.; Aerts, Rien; Freriks, Stef; Röling, Wilfred F. M.; van Bodegom, Peter M.

    2017-01-01

    The climate sensitivity of microbe-mediated soil processes such as carbon and nitrogen cycling offers an interesting case for evaluating the corresponding sensitivity of microbial community composition to environmental change. Better understanding of the degree of linkage between functional and compositional stability would contribute to ongoing efforts to build mechanistic models aiming at predicting rates of microbe-mediated processes. We used an amplicon sequencing approach to test if previously observed large effects of experimental soil warming on C and N cycle fluxes (50–100% increases) in a sub-arctic Sphagnum peatland were reflected in changes in the composition of the soil bacterial community. We found that treatments that previously induced changes to fluxes did not associate with changes in the phylogenetic composition of the soil bacterial community. For both DNA- and RNA-based analyses, variation in bacterial communities could be explained by the hierarchy: spatial variation (12–15% of variance explained) > temporal variation (7–11%) > climate treatment (4–9%). We conclude that the bacterial community in this environment is stable under changing conditions, despite the previously observed sensitivity of process rates—evidence that microbe-mediated soil processes can alter without concomitant changes in bacterial communities. We propose that progress in linking soil microbial communities to ecosystem processes can be advanced by further investigating the relative importance of community composition effects versus physico-chemical factors in controlling biogeochemical process rates in different contexts.

  8. Stable climate and surface mass balance in Svalbard over 1979–2013 despite the Arctic warming

    Directory of Open Access Journals (Sweden)

    C. Lang

    2014-08-01

    Full Text Available With the help of the regional climate model MAR forced by the ERA-Interim reanalysis (MARERA and the MIROC5 global model (MARMIROC5 from the CMIP5 database, we have modelled the climate and surface mass balance of Svalbard at a 10 km resolution over 1979–2013. The integrated total SMB over Svalbard modelled by MARERA is negative (−1.6 Gt yr−1 with a large interannual variability (7.1 Gt but, unlike over Greenland, there has been no acceleration of the surface melt over the past 35 years because of the recent change in atmospheric circulation bringing northerly flows in summer over Svalbard, contrasting the recent observed Arctic warming. However, in 2013, the atmospheric circulation changed to a southwesterly flow over Svalbard causing a record of melt, SMB (−20.4 Gt yr−1 and summer temperature. MIROC5 is significantly colder than ERA-Interim over 1980–2005 but MARMIROC5 is able to improve the near-surface MIROC5 results by simulating not significant SMB differences with MARERA over 1980–2005. On the other hand, MIROC5 does not represent the recent atmospheric circulation shift in summer and induces in MARMIROC5 a significant trend of decreasing SMB (−0.6 Gt yr−2 over 1980–2005.

  9. Carbon and nutrient responses to fire and climate warming in Alaskan arctic tundra

    Science.gov (United States)

    Jiang, Y.; Rastetter, E. B.; Shaver, G. R.; Rocha, A. V.; Kwiatkowski, B.; Pearce, A.; Zhuang, Q.; Mishra, U.

    2015-12-01

    Fire frequency has dramatically increased in the tundra of northern Alaska, which has major implications for the carbon budget of the region and the functioning of these ecosystems that support important wildlife species. We applied the Multiple Element Limitation (MEL) model to investigate both the short- and long-term post-fire succession of plant and soil carbon, nitrogen, and phosphorus fluxes and stocks along a burn severity gradient in the 2007 Anaktuvuk River Fire scar in northern Alaska. We compared the patterns of biomass and soil carbon, nitrogen and phosphorus recoveries with different burn severities and warming intensities. Modeling results indicated that the early regrowth of post-fire tundra vegetation was limited primarily by its canopy photosynthetic potential, rather than nutrient availability. The long-term recovery of C balance from fire disturbance is mainly determined by the internal redistribution of nutrients among ecosystem components, rather than the supply of nutrients from external sources (e.g., nitrogen deposition and fixation, phosphorus weathering). Soil organic matter is the principal source of plant-available nutrients and determines the spatial variation of vegetation biomass across the North Slope of Alaska. Across the North Slope of Alaska, we examined the effects of changes in N and P cycles on tundra C budgets under climate warming. Our results indicate that the ongoing climate warming in Arctic enhances mineralization and leads to a net transfer of nutrient from soil organic matter to vegetation, thereby stimulating tundra plant growth and increased C sequestration in the tundra ecosystems.

  10. Arctic tides from GPS on sea ice

    DEFF Research Database (Denmark)

    Kildegaard Rose, Stine; Skourup, Henriette; Forsberg, René

    The presence of sea-ice in the Arctic Ocean plays a significant role in the Arctic climate. Sea ice dampens the ocean tide amplitude with the result that global tidal models which use only astronomical data perform less accurately in the polar regions. This study presents a kinematic processing...... of Global Positioning System (GPS) buoys placed on sea-ice at five different sites north of Greenland for the study of sea level height and tidal analysis to improve tidal models in the Central Arctic. The GPS measurements are compared with the Arctic tidal model AOTIM-5, which assimilates tide...

  11. An evaluation of the simulations of the Arctic Intermediate Water in climate models and reanalyses

    Institute of Scientific and Technical Information of China (English)

    LI Xiang; SU Jie; ZHAO Jinping

    2014-01-01

    The simulations of the Arctic Intermediate Water in four datasets of climate models and reanalyses, CCSM3, CCSM4, SODA and GLORYS, are analyzed and evaluated. The climatological core temperatures and depths in both CCSM models exhibit deviations over 0.5°C and 200 m from the PHC. SODA reanalysis reproduces relatively reasonable spatial patterns of core temperature and depth, while GLORYS, another reanalysis, shows a remarkable cooling and deepening drift compared with the result at the beginning of the dataset especially in the Eurasian Basin (about 2°C). The heat contents at the depth of intermediate water in the CCSM models are overestimated with large positive errors nearly twice of that in the PHC. To the contrary, the GLORYS in 2009 show a negative error with a similar magnitude, which means the characteristic of the water mass is totally lost. The circulations in the two reanalyses at the depth of intermediate water are more energetic and realistic than those in the CCSMs, which is attributed to the horizontal eddy-permitting reso-lution. The velocity fields and the transports in the Fram Strait are also investigated. The necessity of finer horizontal resolution is concluded again. The northward volume transports are much larger in the two re-analyses, although they are still weak comparing with mooring observations. Finally, an investigation of the impact of assimilation is done with an evidence of the heat input from assimilation. It is thought to be a reason for the good performance in the SODA, while the GLORYS drifts dramatically without assimilation data in the Arctic Ocean.

  12. Sensitivity of the Arctic Climate to Leads in a Coupled Atmosphere-Mixed Layer Ocean Model.

    Science.gov (United States)

    Vavrus, Stephen J.

    1995-02-01

    The thermodynamic sea ice code in a coupled atmosphere-mixed layer ocean GCM has been altered to allow the presence of open water within an ice pack (leads) and a prescribed turbulent oceanic heat flux at the ice bottom. Two experiments with the GCM are then performed: one with leads included and one without. A comparison between the two model runs is presented, in addition to a comparison between observations and the simulation with leads. Selected sea ice and atmospheric variables in the high-latitude Northern Hemisphere are analyzed to assess the sensitivity of these climatic components to the presence of leads and to identify feedback mechanisms that are introduced by leads.The inclusion of leads causes Northern Hemispheric sea ice concentration to decrease in every season, with year-round statistically significant reductions at the highest latitude band (81°N). Using the improved sea ice code, the model's simulation of sea ice concentration in the central Arctic is consistent with observations in every season. Simulated summertime sea ice concentration at 81°N averages 93.8%, which agrees well with observations. There is a pronounced longitudinal variation to the lead fraction in summer, with the smallest values (0.01) neat the Canadian Archipelago and the largest (0.25) north of the East Siberian Sea. Consistent with observations, the model produces wintertime turbulent sensible heat fluxes over leads that are one to two orders of magnitude larger than over adjacent sea ice and of the opposite sign. Annual solar radiation absorption by leads in the central Arctic is 1.8 times as large as over adjacent sea ice, resulting in a summertime shortwave energy gain of over 2.5 W m2 at 8 1°N compared to the model run without leads.The inclusion of leads causes thicker sea ice in every season, because the very rapid ice growth rate in the leads is translated into enhanced accretion at the bottom of adjacent sea ice once a prescribed minimum lead fraction is reached

  13. Climate change and credibility of fish stock agreements : the case of the north-east arctic cod

    OpenAIRE

    Ekerhovd, Nils-Arne

    2010-01-01

    We simulate how an increase in the productivity of the North-East Arctic cod stock would affect the Russian-Norwegian cooperation on the management of the stock. The productivity increase is linked to environmental conditions in the sea and to climate change through a temperature-dependent stock-recruitment relationship, where the numbers of recruits is positively related to the sea temperature given the spawning stock biomass. Increased recruitment and productivity of the stock improved the...

  14. Impact of melt ponds on Arctic sea ice in past and future climate as simulated by MPI-ESN

    OpenAIRE

    E. Roeckner; T. Mauritsen; Esch, M.; Brokopf, R.

    2012-01-01

    The impact of melt ponds on Arctic sea ice is estimated from model simulations of the historical and future climate. The simulations were performed with and without the effect of melt ponds on sea ice melt, respectively. In the last thirty years of the historical simulations, melt ponds develop predominantly in the continental shelf regions and in the Canadian archipelago. Accordingly, the ice albedo in these regions is systematically smaller than in the no-pond simulations, the sea ice melt ...

  15. Impact of melt ponds on Arctic sea ice in past and future climates as simulated by MPI-ESM

    OpenAIRE

    Erich Roeckner; Thorsten Mauritsen; Renate Brokopf

    2012-01-01

    The impact of melt ponds on Arctic sea ice is estimated from model simulations of the historical and future climate. The simulations were performed with and without the effect of melt ponds on sea ice melt, respectively. In the last thirty years of the historical simulations, melt ponds develop predominantly in the continental shelf regions and in the Canadian archipelago. Accordingly, the ice albedo in these regions is systematically smaller than in the no-pond simulations, the sea ice melt ...

  16. Imminent ocean acidification in the Arctic projected with the NCAR global coupled carbon cycle-climate model

    Directory of Open Access Journals (Sweden)

    M. Steinacher

    2009-04-01

    Full Text Available Ocean acidification from the uptake of anthropogenic carbon is simulated for the industrial period and IPCC SRES emission scenarios A2 and B1 with a global coupled carbon cycle-climate model. Earlier studies identified seawater saturation state with respect to aragonite, a mineral phase of calcium carbonate, as a key variable governing impacts on corals and other shell-forming organisms. Globally in the A2 scenario, water saturated by more than 300%, considered suitable for coral growth, vanishes by 2070 AD (CO2≈630 ppm, and the ocean volume fraction occupied by saturated water decreases from 42% to 25% over this century. The largest simulated pH changes worldwide occur in Arctic surface waters, where hydrogen ion concentration increases by up to 185% (ΔpH=−0.45. Projected climate change amplifies the decrease in Arctic surface mean saturation and pH by more than 20%, mainly due to freshening and increased carbon uptake in response to sea ice retreat. Modeled saturation compares well with observation-based estimates along an Arctic transect and simulated changes have been corrected for remaining model-data differences in this region. Aragonite undersaturation in Arctic surface waters is projected to occur locally within a decade and to become more widespread as atmospheric CO2 continues to grow. The results imply that surface waters in the Arctic Ocean will become corrosive to aragonite, with potentially large implications for the marine ecosystem, if anthropogenic carbon emissions are not reduced and atmospheric CO2 not kept below 450 ppm.

  17. Comparative analysis of land, marine, and satellite observations of methane in the lower Atmosphere in the Russian Arctic under conditions of climate change

    Science.gov (United States)

    Anisimov, O. A.; Kokorev, V. A.

    2015-12-01

    Land, marine, and satellite observations have been used to study changes in methane concentrations in the lower atmosphere during the warm months of the year (July through October) in Arctic regions having different potentials for methane production. The Atmospheric Infrared Sounder (AIRS) data for 2002-2013 are used to explore the interplay between local methane sources in the terrestrial region of the Eurasian Arctic and on the Arctic shelf over the warm period of the year. Linear trends in atmospheric methane concentrations over different Arctic regions are calculated, and a hypothesis of the relation of concentration variations to climatic parameters is tested. The combination of land, marine, and satellite observation is used to develop a conceptual model of the atmospheric methane field in the terrestrial part of the Russian Arctic and on the Arctic shelf. It is shown that the modern methane growth rate in the Arctic does not exceed the Northern Hemisphere mean. It is concluded that the methane emission in the Arctic has little effect on global climate compared to other factors.

  18. Spring melt ponds drive Arctic September ice at past, present and future climates in coupled climate simulation

    Science.gov (United States)

    Schroeder, David; Feltham, Danny; Rae, Jamie; Flocco, Daniela; Ridley, Jeff; Blockley, Edd

    2016-04-01

    Stand-alone sea ice simulations with a physical based melt pond model reveal a strong correlation between the simulated spring pond fraction and the observed as well as simulated September sea ice extent for the period 1979 to 2014. This is explained by a positive feedback mechanism: more ponds reduce the albedo; a lower albedo causes more melting; more melting increases pond fraction. This feedback process is a potential reason for the acceleration of Arctic sea ice decrease in the last decade and the failure of many climate models (without an implicit pond model) to simulate the observed decrease. We implemented the Los Alamos sea ice model CICE 5 including our physical based melt pond model into the latest version of the Hadley Centre coupled climate model, HadGEM3. The model surface shortwave radiation scheme has been adjusted to account for pond fraction and depth. We performed three 55-year HadGEM3 simulations with constant external forcing for the years 1985, 2010 and 2035. In all three simulations we find a strong correlation between the April/May pond fraction and the September sea ice extent with correlation coefficients R1985 = -0.86, R2010 = -0.83 and R2035 = -0.79. Based on the correlation we can perform forecasts with remarkable skill values of S1985 = 0.50, S2010 = 0.36 and S2035 = 0.40. We calculate the skill as S = 1 - σferr2/ σref2, where σref2 is the variance of the de-trended climatology and σferr2 the forecast error variance. Altogether our three simulations cover a large range of September sea ice extent from maximum values of 8.5 million km2 for the 1985 run down to 1.5 million km2 for the 2035 run. We demonstrate that spring melt ponds are an important driver for summer ice melt and the consequent minimum ice extent for current and future climate conditions.

  19. The ocean's role in polar climate change: asymmetric Arctic and Antarctic responses to greenhouse gas and ozone forcing.

    Science.gov (United States)

    Marshall, John; Armour, Kyle C; Scott, Jeffery R; Kostov, Yavor; Hausmann, Ute; Ferreira, David; Shepherd, Theodore G; Bitz, Cecilia M

    2014-07-13

    In recent decades, the Arctic has been warming and sea ice disappearing. By contrast, the Southern Ocean around Antarctica has been (mainly) cooling and sea-ice extent growing. We argue here that interhemispheric asymmetries in the mean ocean circulation, with sinking in the northern North Atlantic and upwelling around Antarctica, strongly influence the sea-surface temperature (SST) response to anthropogenic greenhouse gas (GHG) forcing, accelerating warming in the Arctic while delaying it in the Antarctic. Furthermore, while the amplitude of GHG forcing has been similar at the poles, significant ozone depletion only occurs over Antarctica. We suggest that the initial response of SST around Antarctica to ozone depletion is one of cooling and only later adds to the GHG-induced warming trend as upwelling of sub-surface warm water associated with stronger surface westerlies impacts surface properties. We organize our discussion around 'climate response functions' (CRFs), i.e. the response of the climate to 'step' changes in anthropogenic forcing in which GHG and/or ozone-hole forcing is abruptly turned on and the transient response of the climate revealed and studied. Convolutions of known or postulated GHG and ozone-hole forcing functions with their respective CRFs then yield the transient forced SST response (implied by linear response theory), providing a context for discussion of the differing warming/cooling trends in the Arctic and Antarctic. We speculate that the period through which we are now passing may be one in which the delayed warming of SST associated with GHG forcing around Antarctica is largely cancelled by the cooling effects associated with the ozone hole. By mid-century, however, ozone-hole effects may instead be adding to GHG warming around Antarctica but with diminished amplitude as the ozone hole heals. The Arctic, meanwhile, responding to GHG forcing but in a manner amplified by ocean heat transport, may continue to warm at an accelerating rate.

  20. A closer investigation of associations between Autumn Arctic sea ice and central and east Eurasian winter climate

    Science.gov (United States)

    Wang, Shaoyin; Liu, Jiping

    2016-04-01

    Whether recent Arctic sea ice loss is responsible for recent severe winters over mid-latitude continents has emerged as a major debate among climate scientists owing to short records of observations and large internal variability in mid- and high-latitudes. In this study, we divide the evolution of autumn Arctic sea ice extent during 1979-2014 into three epochs, 1979-1986 (high), 1987-2006 (moderate) and 2007-2014 (low), using a regime shift identification method. We then compare the associations between autumn Arctic sea ice and winter climate anomalies over central and eastern Eurasia for the three epochs with focus not only on the mean state, but also the extreme events. The results show robust and detectable signals of sea ice loss in weather and climate over western Siberia and East Asia. For the mean state, anomalous low sea ice extent is associated with a strengthening of the Siberian high pressure, a weakening of westerly winds over north Asia, leading to cold anomalies in central Asia and northern China. For the extreme events, the latitude (speed) of the jet stream shifts southward (reduces), the wave extent amplifies, blocking high events increase over Ural Mountains, leading to increased frequency of cold air outbreaks extending from central Asia to northeast China. These associations bear a high degree of similarity to the observed atmospheric anomalies during the low sea ice epoch. By contrast, the patterns of atmospheric anomalies for the high sea ice epoch are different from those congruent with sea ice variability, which is related to the persistent negative phase of the Arctic Oscillation. We also found that the ENSO plays a minor role in the determination of the observed atmospheric anomalies for the three epochs. Support for these observational analysis is largely corroborated by independent atmospheric model simulations.

  1. Quantifying the Mass Balance of Ice Caps on Severnaya Zemlya, Russian High Arctic. III: Sensitivity of Ice Caps in Severnaya Zemlya to Future Climate Change

    OpenAIRE

    Bassford, R.P.; Siegert, M. J.; J. A. Dowdeswell

    2006-01-01

    A coupled surface mass balance and ice-flow model was used to predict the response of three ice caps on Severnaya Zemlya, Russian Arctic, to the present climate and to future climate changes as postulated by the Intergovernmental Panel on Climate Change (IPCC). Ice cap boundary conditions are derived from recent airborne geophysical surveying (Dowdeswell et al., 2002), and model inputs are constructed from available climate data. Model results indicate that, currently, the state of balance of...

  2. Climate driven changes in hydrology, nutrient cycling, and food web dynamics in surface waters of the Arctic Coastal Plain, Alaska

    Science.gov (United States)

    Koch, J. C.; Wipfli, M.; Schmutz, J.; Gurney, K.

    2011-12-01

    Arctic ecosystems are changing rapidly as a result of a warming climate. While many areas of the arctic are expected to dry as a result of warming, the Arctic Coastal Plain (ACP) of Alaska, which extends from the Brooks Range north to the Beaufort Sea will likely become wetter, because subsurface hydrologic fluxes are constrained by thick, continuous permafrost. This landscape is characterized by large, oriented lakes and many smaller ponds that form in the low centers and troughs/edges of frost polygons. This region provides important breeding habitat for many migratory birds including loons, arctic terns, eiders, shorebirds, and white-fronted geese, among others. Increased hydrologic fluxes may provide a bottom-up control on the success of these species by altering the availability of food resources including invertebrates and fish. This work aimed to 1) characterize surface water fluxes and nutrient availability in the small streams and lake types of two study regions in the ACP, 2) predict how increased hydrological fluxes will affect the lakes, streams, and water chemistry, and 3) use nutrient additions to simulate likely changes in lake chemistry and invertebrate availability. Initial observations suggest that increasing wetland areas and availability of nutrients will result in increased invertebrate abundance, while the potential for drainage and terrestrialization of larger lakes may reduce fish abundance and overwintering habitat. These changes will likely have positive implications for insectivores and negative implications for piscivorous waterfowl.

  3. Influence of Arctic Sea Ice Extent on Polar Cloud Fraction and Vertical Structure and Implications for Regional Climate

    Science.gov (United States)

    Palm, Stephen P.; Strey, Sara T.; Spinhirne, James; Markus, Thorsten

    2010-01-01

    Recent satellite lidar measurements of cloud properties spanning a period of 5 years are used to examine a possible connection between Arctic sea ice amount and polar cloud fraction and vertical distribution. We find an anticorrelation between sea ice extent and cloud fraction with maximum cloudiness occurring over areas with little or no sea ice. We also find that over ice!free regions, there is greater low cloud frequency and average optical depth. Most of the optical depth increase is due to the presence of geometrically thicker clouds over water. In addition, our analysis indicates that over the last 5 years, October and March average polar cloud fraction has increased by about 7% and 10%, respectively, as year average sea ice extent has decreased by 5% 7%. The observed cloud changes are likely due to a number of effects including, but not limited to, the observed decrease in sea ice extent and thickness. Increasing cloud amount and changes in vertical distribution and optical properties have the potential to affect the radiative balance of the Arctic region by decreasing both the upwelling terrestrial longwave radiation and the downward shortwave solar radiation. Because longwave radiation dominates in the long polar winter, the overall effect of increasing low cloud cover is likely a warming of the Arctic and thus a positive climate feedback, possibly accelerating the melting of Arctic sea ice.

  4. The Influence of Arctic Sea Ice Extent on Polar Cloud Fraction and Vertical Structure and Implications for Regional Climate

    Science.gov (United States)

    Palm, Stephen P.; Strey, Sara T.; Spinhirne, James; Markus, Thorsten

    2010-01-01

    Recent satellite lidar measurements of cloud properties spanning a period of five years are used to examine a possible connection between Arctic sea ice amount and polar cloud fraction and vertical distribution. We find an anti-correlation between sea ice extent and cloud fraction with maximum cloudiness occurring over areas with little or no sea ice. We also find that over ice free regions, there is greater low cloud frequency and average optical depth. Most of the optical depth increase is due to the presence of geometrically thicker clouds over water. In addition, our analysis indicates that over the last 5 years, October and March average polar cloud fraction has increased by about 7 and 10 percent, respectively, as year average sea ice extent has decreased by 5 to 7 percent. The observed cloud changes are likely due to a number of effects including, but not limited to, the observed decrease in sea ice extent and thickness. Increasing cloud amount and changes in vertical distribution and optical properties have the potential to affect the radiative balance of the Arctic region by decreasing both the upwelling terrestrial longwave radiation and the downward shortwave solar radiation. Since longwave radiation dominates in the long polar winter, the overall effect of increasing low cloud cover is likely a warming of the Arctic and thus a positive climate feedback, possibly accelerating the melting of Arctic sea ice.

  5. Dynamics of Arctic and Sub-Arctic Climate and Atmospheric Circulation: Diagnosis of Mechanisms and Model Biases Using data Assimilation

    Energy Technology Data Exchange (ETDEWEB)

    Sumant Nigam

    2013-02-05

    These five publications are summarized: Key role of the Atlantic Multidecadal Oscillation in 20th century drought and wet periods over the Great Plains; A Sub-Seasonal Teleconnection Analysis: PNA Development and Its Relationship to the NAO; AMO's Structure and Climate Footprint in Observations and IPCC AR5 Climate Simulations; The Atlantic Multidecadal Oscillation in 20th Century Climate Simulations: Uneven Progress from CMIP3 to CMIP5; and Tropical Atlantic Biases in CCSM4.

  6. Role of Greenland meltwater in the changing Arctic

    Science.gov (United States)

    Dukhovskoy, Dmitry; Proshutinsky, Andrey; Timmermans, Mary-Louise; Myers, Paul; Platov, Gennady; Bamber, Jonathan; Curry, Beth; Somavilla, Raquel

    2016-04-01

    Observational data show that the Arctic ocean-ice-atmosphere system has been changing over the last two decades. Arctic change is manifest in the atypical behavior of the climate indices in the 21st century. Before the 2000s, these indices characterized the quasi-decadal variability of the Arctic climate related to different circulation regimes. Between 1948 and 1996, the Arctic atmospheric circulation alternated between anticyclonic circulation regimes and cyclonic circulation regimes with a period of 10-15 years. Since 1997, however, the Arctic has been dominated by an anticyclonic regime. Previous studies indicate that in the 20th century, freshwater and heat exchange between the Arctic Ocean and the sub-Arctic seas were self-regulated and their interactions were realized via quasi-decadal climate oscillations. What physical processes in the Arctic Ocean - sub-Arctic ocean-ice-atmosphere system are responsible for the observed changes in Arctic climate variability? The presented work is motivated by our hypothesis that in the 21st century, these quasi-decadal oscillations have been interrupted as a result of an additional freshwater source associated with Greenland Ice Sheet melt. Accelerating since the early 1990s, the Greenland Ice Sheet mass loss exerts a significant impact on thermohaline processes in the sub-Arctic seas. Surplus Greenland freshwater, the amount of which is about a third of the freshwater volume fluxed into the region during the 1970s Great Salinity Anomaly event, can spread and accumulate in the sub-Arctic seas influencing convective processes there. It is not clear, however, whether Greenland freshwater can propagate into the interior convective regions in the Labrador Sea and the Nordic Seas. In order to investigate the fate and pathways of Greenland freshwater in the sub-Arctic seas and to determine how and at what rate Greenland freshwater propagates into the convective regions, several numerical experiments using a passive tracer to

  7. Vulnerability and adaptation to climate change in the arctic (VACCA): Implementing recommendations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This report provides recommendations for how Norway's government could move forward with the results from the Arctic Council supported VACCA project, suggesting how concrete activities may be implemented and applied to policy and practice. Based on the results of interviews with Arctic peoples and people involved in Arctic work, combined with desk studies of relevant literature, four Arctic contexts are defined within the dividing lines coastal/non-coastal and urban/non-urban. This report provides up to five concrete recommendations within each context, recommendations for cross-contextual action, and specific projects for further research and action.(auth)

  8. Arctic sea ice bordering on the North Atlantic and intera- nnual climate variations

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Variations of winter Arctic sea ice bordering on the North Atlantic are closely related to climate variations in the same region. When winter North Atlantic Oscillation (NAO) index is positive (negative) anomaly phase, Icelandic Low is obviously deepened and shifts northwards (southwards). Simultaneously, the Subtropical High over the North Atlantic is also intensified, and moves northwards (south-wards). Those anomalies strengthen (weaken) westerly be-tween Icelandic Low and the Subtropical High, and further result in positive (negative) sea surface temperature (SST) anomalies in the mid-latitude of the North Atlantic, and increase (decrease) the warm water transportation from the mid-latitude to the Barents Sea, which causes positive (nega-tive) mixed-layer water temperature anomalies in the south part of the Barents Sea. Moreover, the distribution of anom-aly air temperature clearly demonstrates warming (cooling) in northern Europe and the subarctic regions (including the Barents Sea) and cooling (warming) in Baffin Bay/ Davis Strait. Both of distributions of SST and air temperature anomalies directly result in sea ice decrease (increase) in the Barents/Kara Seas, and sea ice increase (decrease) in Baffin Bay/Davis Strait.

  9. Arctic rapid sea ice loss events in regional coupled climate scenario experiments

    Directory of Open Access Journals (Sweden)

    R. Döscher

    2013-03-01

    Full Text Available Rapid sea ice loss events (RILEs in a mini-ensemble of regional Arctic coupled climate model scenario experiments are analyzed. Mechanisms of sudden ice loss are strongly related to atmospheric circulation conditions and preconditioning by sea ice thinning during the seasons and years before the event. Clustering of events in time suggests a strong control by large-scale atmospheric circulation. Anomalous atmospheric circulation is providing warm air anomalies of up to 5 K and is forcing ice flow, affecting winter ice growth. Even without a seasonal preconditioning during winter, ice drop events can be initiated by anomalous inflow of warm air during summer. It is shown that RILEs can be generated based on atmospheric circulation changes as a major driving force without major competing mechanisms, other than occasional longwave effects during spring and summer. Other anomalous seasonal radiative forcing or short-lived forcers (e.g., soot play minor roles or no role at all in our model. RILEs initiated by ocean forcing do not occur in the model, although cannot be ruled out due to model limitations. Mechanisms found are qualitatively in line with observations of the 2007 RILE.

  10. Arctic rapid sea ice loss events in regional coupled climate scenario experiments

    Directory of Open Access Journals (Sweden)

    R. Döscher

    2012-07-01

    Full Text Available Rapid sea ice loss events (RILEs in a mini-ensemble of regional Arctic coupled climate model scenario experiments are analyzed. Mechanisms of sudden ice loss are strongly related to atmospheric circulation conditions and preconditioning by sea ice thinning during the seasons and years before the event. Clustering of events in time suggests a strong control by large scale atmospheric circulation. Anomalous atmospheric circulation is forcing ice flow and providing warm air affecting winter ice growth. Even without a seasonal preconditioning during winter, ice drop events can be initiated by anomalous inflow of warm air from the Atlantic sector during summer. It is shown that RILE events can be generated solely based on atmospheric circulation changes without possible competing mechanisms, such as anomalous seasonal radiative forcing or short-lived forcers (e.g. soot. Such forces do merely play minor roles or no role at all in our model. Mechanisms found are qualitatively in line with observations of the 2007 RILE.

  11. The Significant Relationship between the Arctic Oscillation (AO) in December and the January Climate over South China

    Institute of Scientific and Technical Information of China (English)

    YANG Hui

    2011-01-01

    Using NCEP/NCAR reanalysis data, the China rainfall and surface temperature data of the China Meteorological Administration, and the Arctic Oscillation (AO) indices of NOAA, the author investigates relationships between the AO and the precipitation and temperature over China. There exists a good relationship between the AO index in December and the succeeding January precipitation over South China,indicating that when the December AO index is positive (negative), the January precipitation over South China increases (decreases). A remarkable negative correlation between the December AO index and the January surface temperature also exists over South China, indicating that when the December AO index is positive (negative), the January temperature over South China drops (rises). The occurrence of this anomalous climate is related to the anomalies of the atmospheric circulation systems. The December AO greatly influences circulation anomalies in January. A positive phase of the AO is found to lead to a stronger subtropical jet over the south side from the Iran Plateau to the Tibetan Plateau. Consequently, it results in a deepening pressure trough around the Bay of Bengal, which transports the warm and wet air to South China continuously. The Siberian High in January is stronger and extends farther southeastward. It results in continual cold air at 1000 hPa pouring into South China, inducing low temperature. Cooperating with the trough of the Bay of Bengal, anomalous precipitation occurs over South China. For the negative phase of the December AO, the opposite situation is observed.

  12. Climate relevant trace gases (N2O and CH4) in the Eurasian Basin (Arctic Ocean)

    Science.gov (United States)

    Verdugo, Josefa; Damm, Ellen; Snoeijs, Pauline; Díez, Beatriz; Farías, Laura

    2016-11-01

    The concentration of greenhouse gases, including nitrous oxide (N2O), methane (CH4), and compounds such as total dimethylsulfoniopropionate (DMSPt), along with other oceanographic variables were measured in the ice-covered Arctic Ocean within the Eurasian Basin (EAB). The EAB is affected by the perennial ice-pack and has seasonal microalgal blooms, which in turn may stimulate microbes involved in trace gas cycling. Data collection was carried out on board the LOMROG III cruise during the boreal summer of 2012. Water samples were collected from the surface to the bottom layer (reaching 4300 m depth) along a South-North transect (SNT), from 82.19°N, 8.75°E to 89.26°N, 58.84°W, crossing the EAB through the Nansen and Amundsen Basins. The Polar Mixed Layer and halocline waters along the SNT showed a heterogeneous distribution of N2O, CH4 and DMSPt, fluctuating between 42-111 and 27-649% saturation for N2O and CH4, respectively; and from 3.5 to 58.9 nmol L-1 for DMSPt. Spatial patterns revealed that while CH4 and DMSPt peaked in the Nansen Basin, N2O was higher in the Amundsen Basin. In the Atlantic Intermediate Water and Arctic Deep Water N2O and CH4 distributions were also heterogeneous with saturations between 52% and 106% and 28% and 340%, respectively. Remarkably, the Amundsen Basin contained less CH4 than the Nansen Basin and while both basins were mostly under-saturated in N2O. We propose that part of the CH4 and N2O may be microbiologically consumed via methanotrophy, denitrification, or even diazotrophy, as intermediate and deep waters move throughout EAB associated with the overturning water mass circulation. This study contributes to baseline information on gas distribution in a region that is increasingly subject to rapid environmental changes, and that has an important role on global ocean circulation and climate regulation.

  13. Using the Arts as a Bridge to Public Understanding of Data-Intensive Earth Science Research through Climate Prisms: The Arctic

    Science.gov (United States)

    Samsel, F.; Deck, L. T.; Wilson, C. J.; Rodriguez-Acosta, M.

    2015-12-01

    An ever-growing body of research in Informal Science Education is showing that the arts contribute greatly to engaging the free-choice science learner. This kind of learning goes on outside of the classroom, notably in science centers and museums, where novel, experiential approaches can be piloted. A new exhibit, Climate Prisms: The Arctic, is being mounted by a team of artists and scientists at the Bradbury Science Museum of Los Alamos National Laboratory. It presents the pipeline from collecting soil samples in the Arctic to analyzing them in the labs to the statistical analysis of the findings and on to the input into the climate model, using prisms of art: visual art, poetry, scientific text, information graphics, field imagery and others. The presentation encourages users to view Arctic science through these different lenses. Each person plots their own path, moving through the content at the pace and level that best enables them to engage with the material. With the entry points through multiple artistic voices, learners hearts and feelings are directly reached, building primarily affective connections and then curiosity, rather than cognitive. The project itself is a large display screen driven by a touch interface designed for individual or small group viewing. Content paths are determined by an underlying system of tags, levels, content categories and related research areas. A screen shows a set of images. Each image can be accessed to provide image-specific information or can be a launching pad for a new set of related content and images that allows the user to continue on their exploration journey. Each person, each time they visit, creates a unique path through over 2000 pieces of content according to the unique set of learning assets and interests they bring with them at that visit. Embedded assessment will log basic demographics and each individual foray through the content. These assessments will be analyzed to explore trends of use and drive

  14. Graduate training in Earth science across borders and disciplines: ArcTrain -"Processes and impacts of climate change in the North Atlantic Ocean and the Canadian Arctic"

    Science.gov (United States)

    Stein, Rüdiger; Kucera, Michal; Walter, Maren; de Vernal, Anne

    2015-04-01

    Due to a complex set of feedback processes collectively known as "polar amplification", the Arctic realm is expected to experience a greater-than-average response to global climate forcing. The cascades of feedback processes that connect the Arctic cryosphere, ocean and atmosphere remain incompletely constrained by observations and theory and are difficult to simulate in climate models. Our capacity to predict the future of the region and assess the impacts of Arctic change processes on global and regional environments hinges on the availability of interdisciplinary experts with strong international experience and understanding of the science/society interface. This is the basis of the International Research Training Group "Processes and impacts of climate change in the North Atlantic Ocean and the Canadian Arctic - ArcTrain", which was initiated in 2013. ArcTrain aims to educate PhD students in an interdisciplinary environment that combines paleoclimatology, physical oceanography, remote sensing and glaciology with comprehensive Earth system modelling, including sea-ice and ice-sheet components. The qualification program for the PhD students includes joint supervision, mandatory research residences at partner institutions, field courses on land and on sea (Floating University), annual meetings and training workshops and a challenging structured training in expert skills and transferrable skills. Its aim is to enhance the career prospects and employability of the graduates in a challenging international job market across academic and applied sectors. ArcTrain is a collaborative project at the University of Bremen and the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven. The German part of the project is designed to continue for nine years and educate three cohorts of twelve PhD students each. The Canadian partners comprise a consortium of eight universities led by the GEOTOP cluster at the Université du Québec à Montréal and including

  15. The Arctic Cooperative Data and Information System: Data Management Support for the NSF Arctic Research Program (Invited)

    Science.gov (United States)

    Moore, J.; Serreze, M. C.; Middleton, D.; Ramamurthy, M. K.; Yarmey, L.

    2013-12-01

    The NSF funds the Advanced Cooperative Arctic Data and Information System (ACADIS), url: (http://www.aoncadis.org/). It serves the growing and increasingly diverse data management needs of NSF's arctic research community. The ACADIS investigator team combines experienced data managers, curators and software engineers from the NSIDC, UCAR and NCAR. ACADIS fosters scientific synthesis and discovery by providing a secure long-term data archive to NSF investigators. The system provides discovery and access to arctic related data from this and other archives. This paper updates the technical components of ACADIS, the implementation of best practices, the value of ACADIS to the community and the major challenges facing this archive for the future in handling the diverse data coming from NSF Arctic investigators. ACADIS provides sustainable data management, data stewardship services and leadership for the NSF Arctic research community through open data sharing, adherence to best practices and standards, capitalizing on appropriate evolving technologies, community support and engagement. ACADIS leverages other pertinent projects, capitalizing on appropriate emerging technologies and participating in emerging cyberinfrastructure initiatives. The key elements of ACADIS user services to the NSF Arctic community include: data and metadata upload; support for datasets with special requirements; metadata and documentation generation; interoperability and initiatives with other archives; and science support to investigators and the community. Providing a self-service data publishing platform requiring minimal curation oversight while maintaining rich metadata for discovery, access and preservation is challenging. Implementing metadata standards are a first step towards consistent content. The ACADIS Gateway and ADE offer users choices for data discovery and access with the clear objective of increasing discovery and use of all Arctic data especially for analysis activities

  16. Enhanced 20th century heat transfer to the Arctic simulated in the context of climate variations over the last millennium

    Directory of Open Access Journals (Sweden)

    J. H. Jungclaus

    2014-07-01

    Full Text Available Oceanic heat transport variations, carried by the northward flowing Atlantic Water, strongly influence Arctic sea-ice distribution, ocean–atmosphere exchanges, and pan-Arctic temperatures. Paleoceanographic reconstructions from marine sediments near Fram Strait have documented a dramatic increase in Atlantic Water temperatures over the 20th century, unprecedented in the last millennium. Here we present results from Earth system model simulations over the last millennium that reproduce and explain reconstructed integrated quantities such as pan-Arctic temperature evolution during the pre-industrial millennium as well as the exceptional Atlantic Water warming in Fram Strait in the 20th century. The associated increase in ocean heat transfer to the Arctic can be traced back to changes in the ocean circulation in the sub-polar North Atlantic. An interplay between a weakening overturning circulation and a strengthening sub-polar gyre as a consequence of 20th century global warming is identified as driving mechanism for the pronounced warming along the Atlantic Water path toward the Arctic. Simulations covering the late Holocene provide a reference frame that allows us to conclude that the changes during the last century are unprecedented in the last 1150 years and that they cannot be explained by internal variability or natural forcing alone.

  17. The regional species richness and genetic diversity of Arctic vegetation reflect both past glaciations and current climate

    DEFF Research Database (Denmark)

    Stewart, L.; Alsos, Inger G.; Bay, Christian

    2016-01-01

    correlated with each other, and both showed a positive relationship with landscape age. Plot species richness showed differing responses for vascular plants, bryophytes and lichens. At this finer scale, the richness of vascular plants was not significantly related to landscape age, which had a small effect...... size compared to the models of bryophyte and lichen richness. Main conclusion Our study suggests that imprints of past glaciations in Arctic vegetation diversity patterns at the regional scale are still detectable today. Since Arctic vegetation is still limited by post-glacial migration lag......, it will most probably also exhibit lags in response to current and future climate change. Our results also suggest that local species richness at the plot scale is more determined by local habitat factors...

  18. A Climate System Model, Numerical Simulation and Climate Predictability

    Institute of Scientific and Technical Information of China (English)

    ZENG Qingcun; WANG Huijun; LIN Zhaohui; ZHOU Guangqing; YU Yongqiang

    2007-01-01

    @@ The implementation of the project has lasted for more than 20 years. As a result, the following key innovative achievements have been obtained, ranging from the basic theory of climate dynamics, numerical model development and its related computational theory to the dynamical climate prediction using the climate system models:

  19. High resilience in the Yamal-Nenets social-ecological system, West Siberian Arctic, Russia.

    Science.gov (United States)

    Forbes, Bruce C; Stammler, Florian; Kumpula, Timo; Meschtyb, Nina; Pajunen, Anu; Kaarlejärvi, Elina

    2009-12-29

    Tundra ecosystems are vulnerable to hydrocarbon development, in part because small-scale, low-intensity disturbances can affect vegetation, permafrost soils, and wildlife out of proportion to their spatial extent. Scaling up to include human residents, tightly integrated arctic social-ecological systems (SESs) are believed similarly susceptible to industrial impacts and climate change. In contrast to northern Alaska and Canada, most terrestrial and aquatic components of West Siberian oil and gas fields are seasonally exploited by migratory herders, hunters, fishers, and domesticated reindeer (Rangifer tarandus L.). Despite anthropogenic fragmentation and transformation of a large proportion of the environment, recent socioeconomic upheaval, and pronounced climate warming, we find the Yamal-Nenets SES highly resilient according to a few key measures. We detail the remarkable extent to which the system has successfully reorganized in response to recent shocks and evaluate the limits of the system's capacity to respond. Our analytical approach combines quantitative methods with participant observation to understand the overall effects of rapid land use and climate change at the level of the entire Yamal system, detect thresholds crossed using surrogates, and identify potential traps. Institutional constraints and drivers were as important as the documented ecological changes. Particularly crucial to success is the unfettered movement of people and animals in space and time, which allows them to alternately avoid or exploit a wide range of natural and anthropogenic habitats. However, expansion of infrastructure, concomitant terrestrial and freshwater ecosystem degradation, climate change, and a massive influx of workers underway present a looming threat to future resilience.

  20. High resilience in the Yamal-Nenets social–ecological system, West Siberian Arctic, Russia

    Science.gov (United States)

    Forbes, Bruce C.; Stammler, Florian; Kumpula, Timo; Meschtyb, Nina; Pajunen, Anu; Kaarlejärvi, Elina

    2009-01-01

    Tundra ecosystems are vulnerable to hydrocarbon development, in part because small-scale, low-intensity disturbances can affect vegetation, permafrost soils, and wildlife out of proportion to their spatial extent. Scaling up to include human residents, tightly integrated arctic social-ecological systems (SESs) are believed similarly susceptible to industrial impacts and climate change. In contrast to northern Alaska and Canada, most terrestrial and aquatic components of West Siberian oil and gas fields are seasonally exploited by migratory herders, hunters, fishers, and domesticated reindeer (Rangifer tarandus L.). Despite anthropogenic fragmentation and transformation of a large proportion of the environment, recent socioeconomic upheaval, and pronounced climate warming, we find the Yamal-Nenets SES highly resilient according to a few key measures. We detail the remarkable extent to which the system has successfully reorganized in response to recent shocks and evaluate the limits of the system's capacity to respond. Our analytical approach combines quantitative methods with participant observation to understand the overall effects of rapid land use and climate change at the level of the entire Yamal system, detect thresholds crossed using surrogates, and identify potential traps. Institutional constraints and drivers were as important as the documented ecological changes. Particularly crucial to success is the unfettered movement of people and animals in space and time, which allows them to alternately avoid or exploit a wide range of natural and anthropogenic habitats. However, expansion of infrastructure, concomitant terrestrial and freshwater ecosystem degradation, climate change, and a massive influx of workers underway present a looming threat to future resilience. PMID:20007776

  1. The influence of global climate change on the environmental fate of persistent organic pollutants: A review with emphasis on the Northern Hemisphere and the Arctic as a receptor

    Science.gov (United States)

    Ma, Jianmin; Hung, Hayley; Macdonald, Robie W.

    2016-11-01

    Following worldwide bans and restrictions on the use of many persistent organic pollutants (POPs) from the late 1970s, their regional and global distributions have become governed increasingly by phase partitioning between environmental reservoirs, such as air, water, soil, vegetation and ice, where POPs accumulated during the original applications. Presently, further transport occurs within the atmospheric and aquatic reservoirs. Increasing temperatures provide thermodynamic forcing to drive these chemicals out of reservoirs, like soil, vegetation, water and ice, and into the atmosphere where they can be transported rapidly by winds and then recycled among environmental media to reach locations where lower temperatures prevail (e.g., polar regions and high elevations). Global climate change, widely considered as global warming, is also manifested by changes in hydrological systems and in the cryosphere; with the latter now exhibiting widespread loss of ice cover on the Arctic Ocean and thawing of permafrost. All of these changes alter the cycling and fate of POPs. There is abundant evidence from observations and modeling showing that climate variation has an effect on POPs levels in biotic and abiotic environments. This article reviews recent progress in research on the effects of climate change on POPs with the intention of promoting awareness of the importance of interactions between climate and POPs in the geophysical and ecological systems.

  2. Analysis of trophic interactions reveals highly plastic response to climate change in a tri-trophic High-Arctic ecosystem

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Schmidt, Niels Martin; Hoye, Toke T.

    2016-01-01

    -Arctic tri-trophic system of flowers, insects and waders (Charadriiformes), with latent factors representing phenology (timing of life history events) and performance (abundance or reproduction success) for each trophic level. The effects derived from the model demonstrated that the time of snowmelt directly...

  3. Monitoring ecosystem dynamics in an Arctic tundra ecosystem using hyperspectral reflectance and a robotic tram system

    Science.gov (United States)

    Goswami, Santonu

    Global change, which includes climate change and the impacts of human disturbance, is altering the provision and sustainability of ecosystem goods and services. These changes have the capacity to initiate cascading affects and complex feedbacks through physical, biological and human subsystems and interactions between them. Understanding the future state of the earth system requires improved knowledge of ecosystem dynamics and long term observations of how these are being impacted by global change. Improving remote sensing methods is essential for such advancement because satellite remote sensing is the only means by which landscape to continental-scale change can be observed. The Arctic appears to be impacted by climate change more than any other region on Earth. Arctic terrestrial ecosystems comprise only 6% of the land surface area on Earth yet contain an estimated 25% of global soil organic carbon, most of which is stored in permafrost. If projected increases in plant productivity do not offset forecast losses of soil carbon to the atmosphere as greenhouse gases, regional to global greenhouse warming could be enhanced. Soil moisture is an important control of land-atmosphere carbon exchange in arctic terrestrial ecosystems. However, few studies to date have examined using remote sensing, or developed remote sensing methods for observing the complex interplay between soil moisture and plant phenology and productivity in arctic landscapes. This study was motivated by this knowledge gap and addressed the following questions as a contribution to a large scale, multi investigator flooding and draining experiment funded by the National Science Foundation near Barrow, Alaska (71°17'01" N, 156°35'48" W): (1) How can optical remote sensing be used to monitor the surface hydrology of arctic landscapes? (2) What are the spatio-temporal dynamics of land-surface phenology (NDVI) in the study area and do hydrological treatment has any effect on inter-annual patterns? (3

  4. Conceptualizing Climate Change in the Context of a Climate System: Implications for Climate and Environmental Education

    Science.gov (United States)

    Shepardson, Daniel P.; Niyogi, Dev; Roychoudhury, Anita; Hirsch, Andrew

    2012-01-01

    Today there is much interest in teaching secondary students about climate change. Much of this effort has focused directly on students' understanding of climate change. We hypothesize, however, that in order for students to understand climate change they must first understand climate as a system and how changes to this system due to both natural…

  5. Arctic shelf flooding: a negative feedback on climate warming during terminations

    Science.gov (United States)

    Blaschek, Michael; Renssen, Hans

    2013-04-01

    heat release and surface warming during the entire year. Our analysis exhibits a surprising connection between increased sea-ice export through Fram Strait and changes in atmospheric winds that result from modifications in the atmospheric circulation, that are forced by changes in differential heating over the East Siberian Shelf and the Nordic Seas. This atmospheric teleconnection clearly shows that regional changes can affect hemispheric changes. In a first comparison with available sea-ice proxy reconstructions our results do not disagree, but show the necessity of increased temporal and spatial coverage of proxy reconstructions for future investigations. Our results indicate that shelf flooding had a significant impact on the climate during the early Holocene, namely reducing sea-ice cover and affecting atmospheric circulation. During terminations this can be considered to be a negative feedback on the progress of the termination, as a shelf area becomes flooded, sea-ice production and extent are likely to increase and reduce high latitude intake of orbitally-forced insolation, slowing down the warming trend. This can be the cause of observed cold reversals during warming phases in the continuous transformation of a glacial to an interglacial climate. This implies that shelf flooding should be taken into account when studying the climate dynamics during all glacial terminations. References Bauch, H.; Mueller-Lupp, T.; Taldenkova, E.; Spielhagen, R.; Kassens, H.; Grootes, P.; Thiede, J.; Heinemeier, J. & Petryashov, V. Chronology of the Holocene transgression at the North Siberian margin, Global and Planetary Change, 2001, 31, 125 - 139 Rigor, I. & Colony, R., Sea-ice production and transport of pollutants in the Laptev Sea, 1979-1993, Science of The Total Environment, Environmental Radioactivity in the Arctic, 1997, 202, 89-110 Tamura, T. & Ohshima, K. I., Mapping of sea ice production in the Arctic coastal polynyas, J. Geophys. Res., AGU, 2011, 116, C07030-

  6. Temporal constraints on future accumulation-area loss of a major Arctic ice cap due to climate change (Vestfonna, Svalbard).

    Science.gov (United States)

    Möller, Marco; Schneider, Christoph

    2015-01-28

    Arctic glaciers and ice caps are major contributors to past, present and future sea-level fluctuations. Continued global warming may eventually lead to the equilibrium line altitudes of these ice masses rising above their highest points, triggering unstoppable downwasting. This may feed future sea-level rise considerably. We here present projections for the timing of equilibrium-line loss at the major Arctic ice cap Vestfonna, Svalbard. The projections are based on spatially distributed climatic mass balance modelling driven by the outputs of multiple climate models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) forced by the Representative Concentration Pathways (RCPs) 2.6, 4.5, 6.0 and 8.5. Results indicate strongly decreasing climatic mass balances over the 21(st) century for all RCPs considered. Glacier-wide mass-balance rates will drop down to -4 m a(-1) w.e. (water equivalent) at a maximum. The date at which the equilibrium line rises above the summit of Vestfonna (630 m above sea level) is calculated to range between 2040 and 2150, depending on scenario.

  7. Cumulative Effects of Climate Warming and Other Human Activities on Freshwaters of Arctic and Subarctic North America

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, David W. [Univ. of Alberta, Edmonton, AB (Canada).Dept. of Biological Sciences; Smol, John P. [Queen' s Univ., Kingston, ON (Canada). Dept. of Biology

    2006-06-15

    Despite their generally isolated geographic locations, the freshwaters of the north are subjected to a wide spectrum of environmental stressors. High-latitude regions are especially sensitive to the effects of recent climatic warming, which have already resulted in marked regime shifts in the biological communities of many Arctic lakes and ponds. Important drivers of these limnological changes have included changes in the amount and duration of snow and ice cover, and, for rivers and lakes in their deltas, the frequency and extent of spring floods. Other important climate-related shifts include alterations in evaporation and precipitation ratios, marked changes in the quality and quantity of lake and river water inflows due to accelerated glacier and permafrost melting, and declining percentages of precipitation that falls as snow. The depletion of stratospheric ozone over the north, together with the clarity of many Arctic lakes, renders them especially susceptible to damage from ultraviolet radiation. In addition, the long-range atmospheric transport of pollutants, coupled with the focusing effects of contaminant transport from biological vectors to some local ecosystems (e.g., salmon nursery lakes, ponds draining seabird colonies) and biomagnification in long food chains, have led to elevated concentrations of many persistent organic pollutants (e.g., insecticides, which have never been used in Arctic regions) and other pollutants (e.g., mercury). Rapid development of gas and oil pipelines, mining for diamonds and metals, increases in human populations, and the development of all-season roads, seaports, and hydroelectric dams will stress northern aquatic ecosystems. The cumulative effects of these stresses will be far more serious than those caused by changing climate alone.

  8. The Role of Disturbance in Arctic Ecosystem Response to a Changing Climate

    Science.gov (United States)

    Hinzman, L. D.

    2014-12-01

    Wildfires in the tundra regions and the boreal forest project an immediate effect upon the surface energy and water budget by drastically altering the surface albedo, roughness, infiltration rates, and moisture absorption capacity in organic soils. Although fires create a sudden and drastic change to the landcover, it is only the beginning of a long process of recovery and perhaps a shift to a different successional pathway. In permafrost regions, these effects become part of a process of long-term (20-50 years) cumulative impacts. Burn severity may largely determine immediate impacts and long-term disturbance trajectories. As transpiration decreases or ceases, soil moisture increases markedly, remaining quite wet throughout the year. Because the insulating quality of the organic layer is removed during fires, permafrost begins to thaw near the surface and warm to greater depths. Within a few years, it may thaw to the point where it can no longer completely refreeze every winter, creating a permanently thawed layer in the soil called a talik. After formation of a talik, soils can drain internally throughout the year. At this point, soils may become quite dry, as the total precipitation received annually in the Arctic is quite low. The local ecological community must continuously adapt to the changing soil thermal and moisture regimes. The wet soils found over shallow permafrost favor black spruce forests. After a fire creates a deeper permafrost table (thicker active layer) the invading tree species tend to be birch or alder. The hydrologic and thermal regime of the soil is the primary factor controlling these vegetation trajectories and the subsequent changes in surface mass and energy fluxes. The complexities of a changing climate accentuate these processes of change and complicate predictions of the resulting vegetation trajectories. Understanding these shifts in vegetative communities and quantifying the consequences of thawing permafrost can only be

  9. Midlatitude atmospheric responses to Arctic sensible heat flux anomalies in Community Climate Model, Version 4

    Science.gov (United States)

    Mills, Catrin M.; Cassano, John J.; Cassano, Elizabeth N.

    2016-12-01

    Possible linkages between Arctic sea ice loss and midlatitude weather are strongly debated in the literature. We analyze a coupled model simulation to assess the possibility of Arctic ice variability forcing a midlatitude response, ensuring consistency between atmosphere, ocean, and ice components. We work with weekly running mean daily sensible heat fluxes with the self-organizing map technique to identify Arctic sensible heat flux anomaly patterns and the associated atmospheric response, without the need of metrics to define the Arctic forcing or measure the midlatitude response. We find that low-level warm anomalies during autumn can build planetary wave patterns that propagate downstream into the midlatitudes, creating robust surface cold anomalies in the eastern United States.

  10. Adaptation in Arctic circumpolar communities: food and water security in a changing climate

    Directory of Open Access Journals (Sweden)

    James Berner

    2016-12-01

    Full Text Available The AMAP Human Health Assessment Group has developed different adaptation strategies through a long-term collaboration with all Arctic countries. Different adaptation strategies are discussed, with examples mainly from native population groups in Alaska.

  11. Sea ice thickness and recent Arctic warming

    Science.gov (United States)

    Lang, Andreas; Yang, Shuting; Kaas, Eigil

    2017-01-01

    The climatic impact of increased Arctic sea ice loss has received growing attention in the last years. However, little focus has been set on the role of sea ice thickness, although it strongly determines surface heat fluxes. Here ensembles of simulations using the EC-Earth atmospheric model (Integrated Forecast System) are performed and analyzed to quantify the atmospheric impacts of Arctic sea ice thickness change since 1982 as revealed by the sea ice model assimilation Global Ice-Ocean Modeling and Assimilation System. Results show that the recent sea ice thinning has significantly affected the Arctic climate, while remote atmospheric responses are less pronounced owing to a high internal atmospheric variability. Locally, the sea ice thinning results in enhancement of near-surface warming of about 1°C per decade in winter, which is most pronounced over marginal sea ice areas with thin ice. This leads to an increase of the Arctic amplification factor by 37%.

  12. The response of high-impact blocking weather systems to climate change

    Science.gov (United States)

    Kennedy, Daniel; Parker, Tess; Woollings, Tim; Harvey, Benjamin; Shaffrey, Len

    2016-07-01

    Midlatitude weather and climate are dominated by the jet streams and associated eastward moving storm systems. Occasionally, however, these are blocked by persistent anticyclonic regimes known as blocking. Climate models generally predict a small decline in blocking frequency under anthropogenic climate change. However, confidence in these predictions is undermined by, among other things, a lack of understanding of the physical mechanisms underlying the change. Here we analyze blocking (mostly in the Euro-Atlantic sector) in a set of sensitivity experiments to determine the effect of different parts of the surface global warming pattern. We also analyze projected changes in the impacts of blocking such as temperature extremes. The results show that enhanced warming both in the tropics and over the Arctic act to strengthen the projected decline in blocking. The tropical changes are more important for the uncertainty in projected blocking changes, though the Arctic also affects the temperature anomalies during blocking.

  13. The integrated Arctic Ocean Observing System (iAOOS: an AOSB-CliC Observing Plan for the International Polar Year

    Directory of Open Access Journals (Sweden)

    Bob Dickson

    2006-03-01

    Full Text Available The debate on the climatic impact of Arctic changeis currently focused on the fate of the perennial sea-ice andthe climatic and social effects of its disappearance. Developmentsin our observing techniques mean that we are in prospect of beingtechnically able to describe the ocean-atmosphere-cryospheresystem of high northern latitudes operating as a complete systemfor the first time. Understanding this system and improving itspredictability in models seems to be our most direct way of extendingthe ability of society to mitigate for or adapt to its changes,including global change. The integrated Arctic OceanObserving System (iAOOS, described here, is a means of piecingtogether the available PIs, gear, ships and funding on the pan-Arcticscale that seems necessary to making the attempt, and the InternationalPolar Year (2007-2009 provides the necessary stimulus for doingso.

  14. Towards improved estimation of the dynamic topography and ocean circulation in the high latitude and arctic ocean: The importance of GOCE

    DEFF Research Database (Denmark)

    Johannessen, J. A.; Raj, R. P.; Nilsen, J. E. Ø.

    2013-01-01

    The Arctic plays a fundamental role in the climate system and shows significant sensitivity to anthropogenic climate forcing and the ongoing climate change. Evidently changes in the Arctic and surrounding seas have far reaching influences on regional and global environment and climate variability...... dynamic topography for studies of the ocean circulation and transport estimates in the Nordic Seas and Arctic Ocean.......The Arctic plays a fundamental role in the climate system and shows significant sensitivity to anthropogenic climate forcing and the ongoing climate change. Evidently changes in the Arctic and surrounding seas have far reaching influences on regional and global environment and climate variability....... In this respect this study combines in-situ hydrographical data, surface drifter data and direct current meter measurements, with coupled sea ice - ocean models, radar altimeter data and the latest GOCE-based geoid in order to estimate and assess the quality, usefulness and validity of the new GOCE derived mean...

  15. ARCTIC FOUNDATIONS, INC. FREEZE BARRIER SYSTEM - SITE TECHNOLOGY CAPSULE

    Science.gov (United States)

    Arctic Foundations, Inc. (AFI), of Anchorage, Alaska has developed a freeze barrier technology designed to prevent the migration of contaminants in groundwater by completely isolating contaminant source areas until appropriate remediation techniques can be applied. With this tec...

  16. Present and Future Surface Mass Budget of Small Arctic Ice Caps in a High Resolution Regional Climate Model

    Science.gov (United States)

    Mottram, Ruth; Langen, Peter; Koldtoft, Iben; Midefelt, Linnea; Hesselbjerg Christensen, Jens

    2016-04-01

    Globally, small ice caps and glaciers make a substantial contribution to sea level rise; this is also true in the Arctic. Around Greenland small ice caps are surprisingly important to the total mass balance from the island as their marginal coastal position means they receive a large amount of precipitation and also experience high surface melt rates. Since small ice caps and glaciers have had a disproportionate number of long-term monitoring and observational schemes in the Arctic, likely due to their relative accessibility, they can also be a valuable source of data. However, in climate models the surface mass balance contributions are often not distinguished from the main ice sheet and the presence of high relief topography is difficult to capture in coarse resolution climate models. At the same time, the diminutive size of marginal ice masses in comparison to the ice sheet makes modelling their ice dynamics difficult. Using observational data from the Devon Ice Cap in Arctic Canada and the Renland Ice Cap in Eastern Greenland, we assess the success of a very high resolution (~5km) regional climate model, HIRHAM5 in capturing the surface mass balance (SMB) of these small ice caps. The model is forced with ERA-Interim and we compare observed mean SMB and the interannual variability to assess model performance. The steep gradient in topography around Renland is challenging for climate models and additional statistical corrections are required to fit the calculated surface mass balance to the high relief topography. Results from a modelling experiment at Renland Ice Cap shows that this technique produces a better fit between modelled and observed surface topography. We apply this statistical relationship to modelled SMB on the Devon Ice Cap and use the long time series of observations from this glacier to evaluate the model and the smoothed SMB. Measured SMB values from a number of other small ice caps including Mittivakkat and A.P. Olsen ice cap are also compared

  17. Climate system model, numerical simulation and climate predictability

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Thanks to its work of past more than 20 years,a research team led by Prof.ZENG Qingcun and Prof.WANG Huijun from the CAS Institute of Atmospheric Physics (IAP) has scored innovative achievements in their studies of basic theory of climate dynamics,numerical model development,its related computational theory,and the dynamical climate prediction using the climate system models.Their work received a second prize of the National Award for Natural Sciences in 2005.

  18. On the effects of constraining atmospheric circulation in a coupled atmosphere-ocean Arctic regional climate model

    Science.gov (United States)

    Berg, Peter; Döscher, Ralf; Koenigk, Torben

    2016-06-01

    Impacts of spectral nudging on simulations of Arctic climate in coupled simulations have been investigated in a set of simulations with a regional climate model (RCM). The dominantly circumpolar circulation in the Arctic lead to weak constraints on the lateral boundary conditions (LBCs) for the RCM, which causes large internal variability with strong deviations from the driving model. When coupled to an ocean and sea ice model, this results in sea ice concentrations that deviate from the observed spatial distribution. Here, a method of spectral nudging is applied to the atmospheric model RCA4 in order to assess the potentials for improving results for the sea ice concentrations when coupled to the RCO ocean-sea ice model. The spectral nudging applied to reanalysis driven simulations significantly improves the generated sea ice regarding its temporal evolution, extent and inter-annual trends, compared to simulations with standard LBC nesting. The method is furthermore evaluated with driving data from two CMIP5 GCM simulations for current and future conditions. The GCM biases are similar to the RCA4 biases with ERA-Interim, however, the spectral nudging still improves the surface winds enough to show improvements in the simulated sea ice. For both GCM downscalings, the spectrally nudged version retains a larger sea ice extent in September further into the future. Depending on the sea ice formulation in the GCM, the temporal evolution of the regional sea ice model can deviate strongly.

  19. Arctic species resilience

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Forchhammer, Mads C.; Jeppesen, Erik

    The peak of biological activities in Arctic ecosystems is characterized by a relative short and intense period between the start of snowmelt until the onset of frost. Recent climate changes have induced larger seasonal variation in both timing of snowmelt as well as changes mean temperatures...... and precipitation. Concurrently, phenological change has been recorded in a wide range of plants and animals, with climate change seemingly being the primary driver of these changes. A major concern is whether species and biological systems embrace the plasticity in their phenological responses needed for tracking...... the predicted increase in climate variability. Whereas species may show relatively high phenological resilience to climate change per se, the resilience of systems may be more constrained by the inherent dependence through consumer-resource interactions across trophic levels. During the last 15 years...

  20. Arctic sea ice in the PlioMIP ensemble: is model performance for modern climates a reliable guide to performance for the past or the future?

    Directory of Open Access Journals (Sweden)

    F. W. Howell

    2015-04-01

    Full Text Available Eight general circulation models have simulated the mid-Pliocene Warm Period (mPWP, 3.264 to 3.025 Ma as part of the Pliocene Modelling Intercomparison Project (PlioMIP. Here, we analyse and compare their simulation of Arctic sea ice for both the pre-industrial and the mid-Pliocene. Mid-Pliocene sea ice thickness and extent is reduced and displays greater variability within the ensemble compared to the pre-industrial. This variability is highest in the summer months, when the model spread in the mid-Pliocene is more than three times larger than the rest of the year. Correlations between mid-Pliocene Arctic temperatures and sea ice extents are almost twice as strong as the equivalent correlations for the pre-industrial simulations. It is suggested that the weaker relationship between pre-industrial Arctic sea ice and temperatures is likely due to the tuning of climate models to achieve an optimal pre-industrial sea ice cover, which may also affect future predictions of Arctic sea ice. Model tuning for the pre-industrial does not appear to be best suited for simulating the different climate state of the mid-Pliocene. This highlights the importance of evaluating climate models through simulation of past climates, and the urgent need for more proxy evidence of sea ice during the Pliocene.

  1. Quantifying the Mass Balance of Ice Caps on Severnaya Zemlya, Russian High Arctic. I: Climate and Mass Balance of the Vavilov Ice Cap

    NARCIS (Netherlands)

    Bassford, R.P.; Siegert, M.J.; Dowdeswell, J.A.; Oerlemans, J.; Glazovsky, A.F.; Macheret, Y.Y.

    2006-01-01

    Due to their remote location within the Russian High Arctic, little is known about the mass balance of ice caps on Severnaya Zemlya now and in the past. Such information is critical, however, to building a global picture of the cryospheric response to climate change. This paper provides a numerical

  2. Amplified North Atlantic warming in the late Pliocene by changes in Arctic gateways

    Science.gov (United States)

    Otto-Bliesner, Bette L.; Jahn, Alexandra; Feng, Ran; Brady, Esther C.; Hu, Aixue; Löfverström, Marcus

    2017-01-01

    Under previous reconstructions of late Pliocene boundary conditions, climate models have failed to reproduce the warm sea surface temperatures reconstructed in the North Atlantic. Using a reconstruction of mid-Piacenzian paleogeography that has the Bering Strait and Canadian Arctic Archipelago Straits closed, however, improves the simulation of the proxy-indicated warm sea surface temperatures in the North Atlantic in the Community Climate System Model. We find that the closure of these small Arctic gateways strengthens the Atlantic Meridional Overturning Circulation, by inhibiting freshwater transport from the Pacific to the Arctic Ocean and from the Arctic Ocean to the Labrador Sea, leading to warmer sea surface temperatures in the North Atlantic. This indicates that the state of the Arctic gateways may influence the sensitivity of the North Atlantic climate in complex ways, and better understanding of the state of these Arctic gateways for past time periods is needed.

  3. Towards a process-based understanding of Holocene polar climate change. Using glacier-fed lake sediments from Arctic Svalbard and Antarctic South Georgia

    OpenAIRE

    2016-01-01

    Earth`s polar regions are undergoing dramatic changes due to ongoing climate change as demonstrated by increasing temperatures, collapsing ice shelves, Arctic sea ice loss and rapid glacier retreat. Driving an accelerating rise in global sea level, this amplified regional response may have devastating global socio-economic consequences in the foreseeable future. Yet the causes and range of polar climate variability remain poorly understood as observational records are short and fragmentary, w...

  4. Operational generation of AVHRR-based cloud products for Europe and the Arctic at EUMETSAT's Satellite Application Facility on Climate Monitoring (CM-SAF

    Directory of Open Access Journals (Sweden)

    F. Kaspar

    2009-04-01

    Full Text Available The Satelite Application Facility on Climate Monitoring has implemented a new processing environment for AVHRR-based climate monitoring products. AVHRR measurements from NOAA-17, NOAA-18 and MetOp-A are utilized to generate daily and monthly means of several cloud parameters for Europe and the Inner Arctic: Cloud fraction, cloud types, cloud phase, cloud top height, cloud optical thickness and cloud liquid water path.

  5. Predicting Climate Feedbacks and Impacts in the Terrestrial Arctic: w14_terraarctic progress report

    Energy Technology Data Exchange (ETDEWEB)

    Coon, Ethan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Atchley, Adam Lee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Berndt, Markus [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Moulton, John David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Harp, Dylan Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Garimella, Rao Veerabhadra [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Svyatsky, Daniil [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wilson, Cathy Jean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-07-14

    Regarding the Arctic Terrestrial Simulator (ATS), previous work solved integrated hydrology (coupled surface/subsurface flow) on multiple polygons, and surface flow over larger domains to guide landscape characterization. Solved thermal hydrology with freeze/thaw dynamics in three dimensions. Ongoing efforts apply state of the art thermal hydrology model to complex topography, and include mesh deformation processes.

  6. Adapting to a Changing World: The United States, Climate Change, and the Arctic Maritime Commons

    Science.gov (United States)

    2007-11-05

    ice brings. Like the gold rush that followed the discovery of gold at Sutter’s Mill in 1849, the opening of the Arctic is resulting in a new gold ... rush , on an international scale, to secure access to the oil the region might contain. 2 The

  7. A comparison of climate changes between Arctic and China in the last 600 years%近600年来北极与中国气候变化的对比

    Institute of Scientific and Technical Information of China (English)

    许娟

    2004-01-01

    A compilation of paleoclimate records from lake sediments, trees, ice cores, and historical documents provide a view of China and Arctic environmental changes in the last 600 years. Many of these changes have also been identified in sedimentary and geochemical signatures in deep-sea sediment cores from the North Atlantic Ocean, Arctic and Greenland and ice cores from the Qinghai-Tibet Plateau, confirming the linkage of environmental changes of different time scales between the Arctic and China. It is shown that the changes of precipitation, temperature and sea ice cover in Arctic were correlated with climate changes in China. This paper also developed a comparative research on the climate changes between Arctic and China both during the Little Ice Age (LIA) and the instrumental observation period. Cycles and trend of temperature variations during LIA and temperature and precipitation during the instrumental observation period are performed. We found some similarities and differences of environmental changes between Arctic and China.

  8. The Arctic Sea ice in the CMIP3 climate model ensemble – variability and anthropogenic change

    Directory of Open Access Journals (Sweden)

    L. K. Behrens

    2012-12-01

    Full Text Available The strongest manifestation of global warming is observed in the Arctic. The warming in the Arctic during the recent decades is about twice as strong as in the global average and has been accompanied by a summer sea ice decline that is very likely unprecedented during the last millennium. Here, Arctic sea ice variability is analyzed in the ensemble of CMIP3 models. Complementary to several previous studies, we focus on regional aspects, in particular on the Barents Sea. We also investigate the changes in the seasonal cycle and interannual variability. In all regions, the models predict a reduction in sea ice area and sea ice volume during 1900–2100. Toward the end of the 21st century, the models simulate higher sea ice area variability in September than in March, whereas the variability in the preindustrial control runs is higher in March. Furthermore, the amplitude and phase of the sea ice seasonal cycle change in response to enhanced greenhouse warming. The amplitude of the sea ice area seasonal cycle increases due to the very strong sea ice area decline in September. The seasonal cycle amplitude of the sea ice volume decreases due to the stronger reduction of sea ice volume in March.

    Multi-model mean estimates for the late 20th century are comparable with observational data only for the entire Arctic and the Central Arctic. In the Barents Sea, differences between the multi-model mean and the observational data are more pronounced. Regional sea ice sensitivity to Northern Hemisphere average surface warming has been investigated.

  9. Arctic tipping points

    OpenAIRE

    Smolkova, Valentina

    2015-01-01

    The Arctic is warming much faster than the entire planet, and this causes severe melting of sea ice. However, the climate of different regions of the Earth is interconnected, and changes in the amount of ice in the Arctic can dramatically affect the climate across the whole planet. Some scientists claim that a possible tipping point is the event of the ice-free Arctic Ocean in summer. Certain predictions point towards ice-free Arctic summers around the year 2050, whereas others pre- dict this...

  10. Investigations of the Climate System Response to Climate Engineering in a Hierarchy of Models

    Science.gov (United States)

    McCusker, Kelly E.

    Global warming due to anthropogenic emissions of greenhouse gases is causing negative impacts on diverse ecological and human systems around the globe, and these impacts are projected to worsen as climate continues to warm. In the absence of meaningful greenhouse gas emissions reductions, new strategies have been proposed to engineer the climate, with the aim of preventing further warming and avoiding associated climate impacts. We investigate one such strategy here, falling under the umbrella of `solar radiation management', in which sulfate aerosols are injected into the stratosphere. We use a global climate model with a coupled mixed-layer depth ocean and with a fully-coupled ocean general circulation model to simulate the stabilization of climate by balancing increasing carbon dioxide with increasing stratospheric sulfate concentrations. We evaluate whether or not severe climate impacts, such as melting Arctic sea ice, tropical crop failure, or destabilization of the West Antarctic ice sheet, could be avoided. We find that while tropical climate emergencies might be avoided by use of stratospheric aerosol injections, avoiding polar emergencies cannot be guaranteed due to large residual climate changes in those regions, which are in part due to residual atmospheric circulation anomalies. We also find that the inclusion of a fully-coupled ocean is important for determining the regional climate response because of its dynamical feedbacks. The efficacy of stratospheric sulfate aerosol injections, and solar radiation management more generally, depends on its ability to be maintained indefinitely, without interruption from a variety of possible sources, such as technological failure, a breakdown in global cooperation, lack of funding, or negative unintended consequences. We next consider the scenario in which stratospheric sulfate injections are abruptly terminated after a multi- decadal period of implementation while greenhouse gas emissions have continued unabated

  11. The importance of freshwater systems to the net atmospheric exchange of carbon dioxide and methane with a rapidly changing high Arctic watershed

    Science.gov (United States)

    Emmerton, Craig A.; St. Louis, Vincent L.; Lehnherr, Igor; Graydon, Jennifer A.; Kirk, Jane L.; Rondeau, Kimberly J.

    2016-10-01

    A warming climate is rapidly changing the distribution and exchanges of carbon within high Arctic ecosystems. Few data exist, however, which quantify exchange of both carbon dioxide (CO2) and methane (CH4) between the atmosphere and freshwater systems, or estimate freshwater contributions to total catchment exchange of these gases, in the high Arctic. During the summers of 2005 and 2007-2012, we quantified CO2 and CH4 concentrations in, and atmospheric exchange with, common freshwater systems in the high Arctic watershed of Lake Hazen, Nunavut, Canada. We identified four types of biogeochemically distinct freshwater systems in the watershed; however mean CO2 concentrations (21-28 µmol L-1) and atmospheric exchange (-0.013 to +0.046 g C-CO2 m-2 day-1) were similar between these systems. Seasonal flooding of ponds bordering Lake Hazen generated considerable CH4 emissions to the atmosphere (+0.008 g C-CH4 m-2 day-1), while all other freshwater systems were minimal emitters of this gas (climates than in the past, which may have implications for moisture availability, landscape cover, and the exchange of CO2 and CH4 of underproductive but expansive polar semidesert ecosystems.

  12. Islands of the Arctic

    Science.gov (United States)

    Overpeck, Jonathan

    2004-02-01

    Few environments on Earth are changing more dramatically than the Arctic. Sea ice retreat and thinning is unprecedented in the period of the satellite record. Surface air temperatures are the warmest in centuries. The biology of Arctic lakes is changing like never before in millennia. Everything is pointing to the meltdown predicted by climate model simulations for the next 100 years. At the same time, the Arctic remains one of the most pristine and beautiful places on Earth. For both those who know the Arctic and those who want to know it, this book is worth its modest price. There is much more to the Arctic than its islands, but there's little doubt that Greenland and the major northern archipelagos can serve as a great introduction to the environment and magnificence of the Arctic. The book uses the islands of the Arctic to give a good introduction to what the Arctic environment is all about. The first chapter sets the stage with an overview of the geography of the Arctic islands, and this is followed by chapters that cover many key aspects of the Arctic: the geology (origins), weather and climate, glaciers, ice sheets, sea ice, permafrost and other frozen ground issues, coasts, rivers, lakes, animals, people, and environmental impacts. The material is pitched at a level well suited for the interested layperson, but the book will also appeal to those who study the science of the Arctic.

  13. Improvement in Simulation of Eurasian Winter Climate Variability with a Realistic Arctic Sea Ice Condition in an Atmospheric GCM

    Science.gov (United States)

    Lim, Young-Kwon; Ham, Yoo-Geun; Jeong, Jee-Hoon; Kug, Jong-Seong

    2012-01-01

    The present study investigates how much a realistic Arctic sea ice condition can contribute to improve simulation of the winter climate variation over the Eurasia region. Model experiments are set up using different sea ice boundary conditions over the past 24 years (i.e., 1988-2011). One is an atmospheric model inter-comparison (AMIP) type of run forced with observed sea-surface temperature (SST), sea ice, and greenhouse gases (referred to as Exp RSI), and the other is the same as Exp RSI except for the sea ice forcing, which is a repeating climatological annual cycle (referred to as Exp CSI). Results show that Exp RSI produces the observed dominant pattern of Eurasian winter temperatures and their interannual variation better than Exp CSI (correlation difference up to approx. 0.3). Exp RSI captures the observed strong relationship between the sea ice concentration near the Barents and Kara seas and the temperature anomaly across Eurasia, including northeastern Asia, which is not well captured in Exp CSI. Lagged atmospheric responses to sea ice retreat are examined using observations to understand atmospheric processes for the Eurasian cooling response including the Arctic temperature increase, sea-level pressure increase, upper-level jet weakening and cold air outbreak toward the mid-latitude. The reproducibility of these lagged responses by Exp RSI is also evaluated.

  14. Near-surface meteorology during the Arctic Summer Cloud Ocean Study (ASCOS: evaluation of reanalyses and global climate models

    Directory of Open Access Journals (Sweden)

    G. de Boer

    2013-07-01

    Full Text Available Atmospheric measurements from the Arctic Summer Cloud Ocean Study (ASCOS are used to evaluate the performance of three reanalyses (ERA-Interim, NCEP/NCAR and NCEP/DOE and two global climate models (CAM5 and NASA GISS ModelE2 in simulation of the high Arctic environment. Quantities analyzed include near surface meteorological variables such as temperature, pressure, humidity and winds, surface-based estimates of cloud and precipitation properties, the surface energy budget, and lower atmospheric temperature structure. In general, the models perform well in simulating large scale dynamical quantities such as pressure and winds. Near-surface temperature and lower atmospheric stability, along with surface energy budget terms are not as well represented due largely to errors in simulation of cloud occurrence, phase and altitude. Additionally, a development version of CAM5, which features improved handling of cloud macro physics, is demonstrated to improve simulation of cloud properties and liquid water amount. The ASCOS period additionally provides an excellent example of the need to evaluate individual budget terms, rather than simply evaluating the net end product, with large compensating errors between individual surface energy budget terms resulting in the best net energy budget.

  15. Near-Surface Meteorology During the Arctic Summer Cloud Ocean Study (ASCOS): Evaluation of Reanalyses and Global Climate Models.

    Science.gov (United States)

    De Boer, G.; Shupe, M.D.; Caldwell, P.M.; Bauer, Susanne E.; Persson, O.; Boyle, J.S.; Kelley, M.; Klein, S.A.; Tjernstrom, M.

    2014-01-01

    Atmospheric measurements from the Arctic Summer Cloud Ocean Study (ASCOS) are used to evaluate the performance of three atmospheric reanalyses (European Centre for Medium Range Weather Forecasting (ECMWF)- Interim reanalysis, National Center for Environmental Prediction (NCEP)-National Center for Atmospheric Research (NCAR) reanalysis, and NCEP-DOE (Department of Energy) reanalysis) and two global climate models (CAM5 (Community Atmosphere Model 5) and NASA GISS (Goddard Institute for Space Studies) ModelE2) in simulation of the high Arctic environment. Quantities analyzed include near surface meteorological variables such as temperature, pressure, humidity and winds, surface-based estimates of cloud and precipitation properties, the surface energy budget, and lower atmospheric temperature structure. In general, the models perform well in simulating large-scale dynamical quantities such as pressure and winds. Near-surface temperature and lower atmospheric stability, along with surface energy budget terms, are not as well represented due largely to errors in simulation of cloud occurrence, phase and altitude. Additionally, a development version of CAM5, which features improved handling of cloud macro physics, has demonstrated to improve simulation of cloud properties and liquid water amount. The ASCOS period additionally provides an excellent example of the benefits gained by evaluating individual budget terms, rather than simply evaluating the net end product, with large compensating errors between individual surface energy budget terms that result in the best net energy budget.

  16. Land-Cover and Land-Use Change (LCLUC) Interactions with Climate in the Eurasian Arctic: Past and new projects in the NASA LCLUC program

    Science.gov (United States)

    Gutman, G.

    2009-12-01

    An overview of the studies conducted in the framework of the NASA Land-Cover/Land- Use Change Program focused on the Eurasian Arctic will be presented. It includes discussion of vegetation changes under climate warming and implications to carbon cycle, changes in environmental pollution, hydrologic cycle, and impacts on society. Climate change can affect land cover in the Arctic through changes in the surface reflectivity and hydrology due to changes in snow melt timing; impacts of black carbon emitted by fires and settled on bright surfaces; changes in sea ice and the consequent change in ocean circulation affecting vegetation cover patterns indirectly; and changes in the amounts of greenhouse gases emission due to permafrost melting, especially in peat lands, as warming progresses. The Arctic Eurasia is being affected by global and regional external factors that are causing its change and the positive feedbacks to this forcing may further exaggerate the situation. If the warming trend continues it will have a tremendous impact on all aspects of land cover in the Arctic region with considerable consequences at the global scale. It will cause significant changes in the natural land cover, and perhaps even greater changes in the areas where the land cover has already been considerably modified by human activities. Major changes have already taken place in how land is used in the Arctic. In many regions, there has been a clear shift from the land use practiced by indigenous people to intensive exploitation of the land for commercial and industrial uses. This presentation will synthesize the results of the past NASA LCLUC projects and will showcase some new additions to the program that are relevant to the Arctic climate/environment - land-cover interactions.

  17. Arctic Watch

    Science.gov (United States)

    Orcutt, John; Baggeroer, Arthur; Mikhalevsky, Peter; Munk, Walter; Sagen, Hanne; Vernon, Frank; Worcester, Peter

    2015-04-01

    The dramatic reduction of sea ice in the Arctic Ocean will increase human activities in the coming years. This will be driven by increased demand for energy and the marine resources of an Arctic Ocean more accessible to ships. Oil and gas exploration, fisheries, mineral extraction, marine transportation, research and development, tourism and search and rescue will increase the pressure on the vulnerable Arctic environment. Synoptic in-situ year-round observational technologies are needed to monitor and forecast changes in the Arctic atmosphere-ice-ocean system at daily, seasonal, annual and decadal scales to inform and enable sustainable development and enforcement of international Arctic agreements and treaties, while protecting this critical environment. This paper will discuss multipurpose acoustic networks, including subsea cable components, in the Arctic. These networks provide communication, power, underwater and under-ice navigation, passive monitoring of ambient sound (ice, seismic, biologic and anthropogenic), and acoustic remote sensing (tomography and thermometry), supporting and complementing data collection from platforms, moorings and autonomous vehicles. This paper supports the development and implementation of regional to basin-wide acoustic networks as an integral component of a multidisciplinary, in situ Arctic Ocean Observatory.

  18. UAV Deployed Sensor System for Arctic Ocean Remote Sensing

    Science.gov (United States)

    Palo, S. E.; Lawrence, D.; Weibel, D.; LoDolce, G.; Krist, S.; Crocker, I.; Maslanik, J. A.

    2012-12-01

    The Marginal Ice Zone Observations and Processes Experiment (MIZOPEX), is an Arctic field project scheduled for summer 2013. The goals of the project are to understand how warming of the marginal ice zone affects sea ice melt and if this warming has been over or underestimated by satellite measurements. To achieve these goals calibrated physical measurements, both remote and in-situ, of the marginal ice zone over scales of square kilometers with a resolution of square meters is required. This will be accomplished with a suite of unmanned aerial vehicles (UAVs) equipped with both remote sensing and in-situ instruments, air deployed microbuoys, and ship deployed buoys. In this talk we will present details about the air-deployed micro-buoy (ADMB) and self-deployed surface-sonde (SDSS) components of the MIZOPEX project, developed at the University of Colorado. These systems were designed to explore the potential of low-cost, on-demand access to high-latitude areas of important scientific interest. Both the ADMB and SDSS share a common measurement suite with the capability to measure water temperature at three distinct depths and provide position information via GPS. The ADMBs are dropped from the InSitu ScanEagle UAV and expected to operate and log ocean temperatures for 14 days. The SDSS are micro UAVs that are designed to fly one-way to a region of interest and land at specified coordinates, thereafter becoming a surface sensor similar to the ADMB. A ScanEagle will periodically return to the deployment zone to gather ADMB/SDSS data via low power radio links. Design decisions based upon operational constraints and the current status of the ADMB and SDSS will be presented.

  19. Freshwater and its role in the Arctic Marine System: Sources, disposition, storage, export, and physical and biogeochemical consequences in the Arctic and global oceans

    Science.gov (United States)

    Carmack, E. C.; Yamamoto-Kawai, M.; Haine, T. W. N.; Bacon, S.; Bluhm, B. A.; Lique, C.; Melling, H.; Polyakov, I. V.; Straneo, F.; Timmermans, M.-L.; Williams, W. J.

    2016-03-01

    The Arctic Ocean is a fundamental node in the global hydrological cycle and the ocean's thermohaline circulation. We here assess the system's key functions and processes: (1) the delivery of fresh and low-salinity waters to the Arctic Ocean by river inflow, net precipitation, distillation during the freeze/thaw cycle, and Pacific Ocean inflows; (2) the disposition (e.g., sources, pathways, and storage) of freshwater components within the Arctic Ocean; and (3) the release and export of freshwater components into the bordering convective domains of the North Atlantic. We then examine physical, chemical, or biological processes which are influenced or constrained by the local quantities and geochemical qualities of freshwater; these include stratification and vertical mixing, ocean heat flux, nutrient supply, primary production, ocean acidification, and biogeochemical cycling. Internal to the Arctic the joint effects of sea ice decline and hydrological cycle intensification have strengthened coupling between the ocean and the atmosphere (e.g., wind and ice drift stresses, solar radiation, and heat and moisture exchange), the bordering drainage basins (e.g., river discharge, sediment transport, and erosion), and terrestrial ecosystems (e.g., Arctic greening, dissolved and particulate carbon loading, and altered phenology of biotic components). External to the Arctic freshwater export acts as both a constraint to and a necessary ingredient for deep convection in the bordering subarctic gyres and thus affects the global thermohaline circulation. Geochemical fingerprints attained within the Arctic Ocean are likewise exported into the neighboring subarctic systems and beyond. Finally, we discuss observed and modeled functions and changes in this system on seasonal, annual, and decadal time scales and discuss mechanisms that link the marine system to atmospheric, terrestrial, and cryospheric systems.

  20. Wave Climate and Wave Mixing in the Marginal Ice Zones of Arctic Seas, Observations and Modelling

    Science.gov (United States)

    2015-09-30

    PROJECTS Section). With the group of Rogers, observation/modeling study of an energetic wave event in the Arctic marginal zone was conducted ...floe. (right) Surface elevation in the lee of a 5 mm thick polypropylene floe (thick black curves) and incident wave (grey), normalised with respect...Toffoli, A., Marusic, I., Klewicki, J., Hutchins, N., Suslov, S., Walker, D., Chung, D., “A Thermally Stratified Sea-Ice-Wave Interaction Facility”, ARC

  1. Climate Change and International Competition: the US Army in the Arctic Environment

    Science.gov (United States)

    2015-05-21

    texts/unclos/closindx.htm. 42 Ibid. 43 Natalie Mychajlyszyn, “The Arctic: Geopolitical Issues,” October 24, 2008, Canadian Parliamentary Information...ensure the Army forces are prepared to prevent conflict, shape the security environment, and win wars.”112 Heeding the advice of Perkins, this section...senior Non Commissioned Officers can remain in a duty location longer and provide important advice , the commanding officer is ultimately responsible

  2. Biases of the Arctic climate in a regional ocean-sea ice-atmosphere coupled model:an annual validation

    Institute of Scientific and Technical Information of China (English)

    LIU Xiying

    2014-01-01

    The Coupling of three model components, WRF/PCE (polar climate extension version of weather research and forecasting model ( WRF)), ROMS (regional ocean modeling system), and CICE (community ice code), has been implemented, and the regional atmosphere-ocean-sea ice coupled model named WRF/PCE-ROMS-CICE has been validated against ERA-interim reanalysis data sets for 1989. To better understand the reasons that generate model biases, the WRF/PCE-ROMS-CICE results were compared with those of its components, the WRF/PCE and the ROMS-CICE. There are cold biases in surface air temperature (SAT) over the Arctic Ocean, which contribute to the sea ice concentration (SIC) and sea surface temperature (SST) biases in the results of the WRF/PCE-ROMS-CICE. The cold SAT biases also appear in results of the atmo-spheric component with a mild temperature in winter and similar temperature in summer. Compared to results from the WRF/PCE, due to influences of different distributions of the SIC and the SST and inclusion of interactions of air-sea-sea ice in the WRF/PCE-ROMS-CICE, the simulated SAT has new features. These influences also lead to apparent differences at higher levels of the atmosphere, which can be thought as responses to biases in the SST and sea ice extent. There are similar atmospheric responses in feature of distribution to sea ice biases at 700 and 500 hPa, and the strength of responses weakens when the pressure decreases in January. The atmospheric responses in July reach up to 200 hPa. There are surplus sea ice ex-tents in the Greenland Sea, the Barents Sea, the Davis Strait and the Chukchi Sea in winter and in the Beau-fort Sea, the Chukchi Sea, the East Siberian Sea and the Laptev Sea in summer in the ROMS-CICE. These differences in the SIC distribution can all be explained by those in the SST distributions. These features in the simulated SST and SIC from ROMS-CICE also appear in the WRF/PCE-ROMS-CICE. It is shown that the performance of the WRF/PCE-ROMS-CICE is

  3. Climate change impacts on seals and whales in the North Atlantic Arctic and adjacent shelf seas.

    Science.gov (United States)

    Kovacs, Kit M; Lydersen, Christian

    2008-01-01

    In a warmer Arctic, endemic marine mammal species will face extreme levels of habitat change, most notably a dramatic reduction in sea ice. Additionally, the physical environmental changes, including less ice and increased water (and air) temperatures will result in alterations to the forage base of arctic marine mammals, including density and distributional shifts in their prey, as well as potential losses of some of their traditionally favoured fat-rich prey species. In addition they are likely to face increased competition from invasive temperate species, increased predation from species formerly unable to access them in areas of extensive sea ice or simply because the water temperature was restrictive, increased disease risk and perhaps also increased risks from contaminants. Over the coming decades it is also likely that arctic marine mammals will face increased impacts from human traffic and development in previously inaccessible, ice-covered areas. Impacts on ice-associated cetaceans are difficult to predict because the reasons for their affiliation with sea ice are not clearly understood. But, it is certain that ice-breeding seals will have marked, or total, breeding-habitat loss in their traditional breeding areas and will certainly undergo distributional changes and in all probability abundance reductions. If species are fixed in traditional spatial and temporal cycles, and are unable to shift them within decadal time scales, some populations will go extinct. In somewhat longer time frames, species extinctions can also be envisaged.

  4. Radiocarbon age-offsets in an arctic lake reveal the long-term response of permafrost carbon to climate change

    Science.gov (United States)

    Gaglioti, Benjamin V.; Mann, Daniel H.; Jones, Benjamin M.; Pohlman, John W.; Kunz, Michael L.; Wooller, Matthew J.

    2014-01-01

    Continued warming of the Arctic may cause permafrost to thaw and speed the decomposition of large stores of soil organic carbon (OC), thereby accentuating global warming. However, it is unclear if recent warming has raised the current rates of permafrost OC release to anomalous levels or to what extent soil carbon release is sensitive to climate forcing. Here we use a time series of radiocarbon age-offsets (14C) between the bulk lake sediment and plant macrofossils deposited in an arctic lake as an archive for soil and permafrost OC release over the last 14,500 years. The lake traps and archives OC imported from the watershed and allows us to test whether prior warming events stimulated old carbon release and heightened age-offsets. Today, the age-offset (2 ka; thousand of calibrated years before A.D. 1950) and the depositional rate of ancient OC from the watershed into the lake are relatively low and similar to those during the Younger Dryas cold interval (occurring 12.9–11.7 ka). In contrast, age-offsets were higher (3.0–5.0 ka) when summer air temperatures were warmer than present during the Holocene Thermal Maximum (11.7–9.0 ka) and Bølling-Allerød periods (14.5–12.9 ka). During these warm times, permafrost thaw contributed to ancient OC depositional rates that were ~10 times greater than today. Although permafrost OC was vulnerable to climate warming in the past, we suggest surface soil organic horizons and peat are presently limiting summer thaw and carbon release. As a result, the temperature threshold to trigger widespread permafrost OC release is higher than during previous warming events.

  5. Seasonality of global and Arctic black carbon processes in the Arctic Monitoring and Assessment Programme models

    Science.gov (United States)

    Mahmood, Rashed; Salzen, Knut; Flanner, Mark; Sand, Maria; Langner, Joakim; Wang, Hailong; Huang, Lin

    2016-06-01

    This study quantifies black carbon (BC) processes in three global climate models and one chemistry transport model, with focus on the seasonality of BC transport, emissions, wet and dry deposition in the Arctic. In the models, transport of BC to the Arctic from lower latitudes is the major BC source for this region. Arctic emissions are very small. All models simulated a similar annual cycle of BC transport from lower latitudes to the Arctic, with maximum transport occurring in July. Substantial differences were found in simulated BC burdens and vertical distributions, with Canadian Atmospheric Global Climate Model (CanAM) (Norwegian Earth System Model, NorESM) producing the strongest (weakest) seasonal cycle. CanAM also has the shortest annual mean residence time for BC in the Arctic followed by Swedish Meteorological and Hydrological Institute Multiscale Atmospheric Transport and Chemistry model, Community Earth System Model, and NorESM. Overall, considerable differences in wet deposition efficiencies in the models exist and are a leading cause of differences in simulated BC burdens. Results from model sensitivity experiments indicate that convective scavenging outside the Arctic reduces the mean altitude of BC residing in the Arctic, making it more susceptible to scavenging by stratiform (layer) clouds in the Arctic. Consequently, scavenging of BC in convective clouds outside the Arctic acts to substantially increase the overall efficiency of BC wet deposition in the Arctic, which leads to low BC burdens and a more pronounced seasonal cycle compared to simulations without convective BC scavenging. In contrast, the simulated seasonality of BC concentrations in the upper troposphere is only weakly influenced by wet deposition in stratiform clouds, whereas lower tropospheric concentrations are highly sensitive.

  6. 2.8 Million Years of Arctic Climate Change from Deep Drilling at Lake El'gygytgyn, NE Russia

    Science.gov (United States)

    Melles, M.; Brigham-Grette, J.; Minyuk, P.; Wennrich, V.; Nowaczyk, N.; DeConto, R.; Anderson, P.; Andreev, A.; Haltia-Hovi, E.; Kukkonen, M.; Lozhkin, A.; Rosén, P.; Tarasov, P.

    2012-12-01

    Scientific deep drilling at Lake El'gygtygyn in Chukotka, northeastern Russia (67.5 °N, 172 °E) revealed the first high-resolution record of environmental history in the Arctic that spans the past 2.8 Ma continuously (Melles et al. 2012). In this presentation we focus on the end-member glacial and interglacial climatic conditions during this period as clearly reflected in the pelagic lake sediments recovered. Peak glacial conditions, when mean annual air temperatures at least 4 (± 0.5) °C lower than today led to perennial lake ice (Nolan 2012), first appeared at Lake El'gygytgyn 2.602 - 2.598 Ma ago, during marine isotope stage (MIS) 104. These pervasive glacial episodes gradually increase in frequency from ~2.3 to ~1.8 Ma, eventually concurring with all glacials and several stadials reflected globally in stacked marine isotope records. Particularly warm interglacials, in contrast, experienced a long ice-free season and enhanced nutrient supply from the catchment, which allowed for significantly higher primary production than today. These settings were most pronounced for MIS 11c, 31, 49, 55, 77, 87, 91, and 93. Their exceptional character becomes evident based upon pollen-based climate reconstructions in selected interglacials, showing that the mean temperature of the warmest month and the annual precipitation during the thermal maxima of MIS 11c and 31 ("super" interglacials) were 4-5 °C and ~300 mm higher than those of MIS 1 and 5e ("normal" interglacials), respectively. According to climate simulations, the exceptional warm and moist climates at least during MIS 11c cannot be explained by the natural variability in Earth's orbital parameters and greenhouse gas concentrations alone. A remarkable coincidence of the super interglacials at Lake El'gygytgyn with diatomite layers in the Antarctic ANDRILL 1B, which reflect periods of a diminished West Antarctic Ice Sheet (WAIS) (Naish et al. 2009, Pollard and DeConto 2009), suggests intra-hemispheric climate

  7. Data Acquisition System for Russian Arctic Magnetometer Network

    Science.gov (United States)

    Janzhura, A.; Troshichev, O. A.; Takahashi, K.

    2010-12-01

    Monitoring of magnetic activity in the auroral zone is very essential for space weather problem. The big part of northern auroral zone lies in the Russian sector of Arctica. The Russian auroral zone stations are located far from the proper infrastructure and communications, and getting the data from the stations is complicated and nontrivial task. To resolve this problem a new acquisition system for magnetometers was implemented and developed in last few years, with the magnetic data transmission in real time that is important for many forecasting purpose. The system, based on microprocessor modules, is very reliable in hush climatic conditions. The information from the magnetic sensors transmits to AARI data center by satellite communication system and is presented at AARI web pages. This equipment upgrading of Russian polar magnetometer network is supported by the international RapidMag program.

  8. A 350 ka record of climate change from Lake El'gygytgyn, Far East Russian Arctic: refining the pattern of climate modes by means of cluster analysis

    Directory of Open Access Journals (Sweden)

    U. Frank

    2013-07-01

    Full Text Available Rock magnetic, biochemical and inorganic records of the sediment cores PG1351 and Lz1024 from Lake El'gygytgyn, Chukotka peninsula, Far East Russian Arctic, were subject to a hierarchical agglomerative cluster analysis in order to refine and extend the pattern of climate modes as defined by Melles et al. (2007. Cluster analysis of the data obtained from both cores yielded similar results, differentiating clearly between the four climate modes warm, peak warm, cold and dry, and cold and moist. In addition, two transitional phases were identified, representing the early stages of a cold phase and slightly colder conditions during a warm phase. The statistical approach can thus be used to resolve gradual changes in the sedimentary units as an indicator of available oxygen in the hypolimnion in greater detail. Based upon cluster analyses on core Lz1024, the published succession of climate modes in core PG1351, covering the last 250 ka, was modified and extended back to 350 ka. Comparison to the marine oxygen isotope (δ18O stack LR04 (Lisiecki and Raymo, 2005 and the summer insolation at 67.5° N, with the extended Lake El'gygytgyn parameter records of magnetic susceptibility (κLF, total organic carbon content (TOC and the chemical index of alteration (CIA; Minyuk et al., 2007, revealed that all stages back to marine isotope stage (MIS 10 and most of the substages are clearly reflected in the pattern derived from the cluster analysis.

  9. Prediction of the Arctic Oscillation in Boreal Winter by Dynamical Seasonal Forecasting Systems

    Science.gov (United States)

    Kang, Daehyun; Lee, Myong-In; Im, Jungho; Kim, Daehyun; Kim, Hye-Mi; Kang, Hyun-Suk; Schubert, Siegfried D.; Arribas, Alberto; MacLachlan, Craig

    2014-01-01

    This study assesses the skill of boreal winter Arctic Oscillation (AO) predictions with state-of-the-art dynamical ensemble prediction systems (EPSs): GloSea4, CFSv2, GEOS-5, CanCM3, CanCM4, and CM2.1. Long-term reforecasts with the EPSs are used to evaluate how well they represent the AO and to assess the skill of both deterministic and probabilistic forecasts of the AO. The reforecasts reproduce the observed changes in the large-scale patterns of the Northern Hemispheric surface temperature, upper level wind, and precipitation associated with the different phases of the AO. The results demonstrate that most EPSs improve upon persistence skill scores for lead times up to 2 months in boreal winter, suggesting some potential for skillful prediction of the AO and its associated climate anomalies at seasonal time scales. It is also found that the skill of AO forecasts during the recent period (1997-2010) is higher than that of the earlier period (1983-1996).

  10. Climate Change Education in Earth System Science

    Science.gov (United States)

    Hänsel, Stephanie; Matschullat, Jörg

    2013-04-01

    The course "Atmospheric Research - Climate Change" is offered to master Earth System Science students within the specialisation "Climate and Environment" at the Technical University Bergakademie Freiberg. This module takes a comprehensive approach to climate sciences, reaching from the natural sciences background of climate change via the social components of the issue to the statistical analysis of changes in climate parameters. The course aims at qualifying the students to structure the physical and chemical basics of the climate system including relevant feedbacks. The students can evaluate relevant drivers of climate variability and change on various temporal and spatial scales and can transform knowledge from climate history to the present and the future. Special focus is given to the assessment of uncertainties related to climate observations and projections as well as the specific challenges of extreme weather and climate events. At the end of the course the students are able to critically reflect and evaluate climate change related results of scientific studies and related issues in media. The course is divided into two parts - "Climate Change" and "Climate Data Analysis" and encompasses two lectures, one seminar and one exercise. The weekly "Climate change" lecture transmits the physical and chemical background for climate variation and change. (Pre)historical, observed and projected climate changes and their effects on various sectors are being introduced and discussed regarding their implications for society, economics, ecology and politics. The related seminar presents and discusses the multiple reasons for controversy in climate change issues, based on various texts. Students train the presentation of scientific content and the discussion of climate change aspects. The biweekly lecture on "Climate data analysis" introduces the most relevant statistical tools and methods in climate science. Starting with checking data quality via tools of exploratory

  11. Polar Cyclone Identification from 4D Climate Data in a Knowledge-Driven Visualization System

    Directory of Open Access Journals (Sweden)

    Feng Wang

    2016-09-01

    Full Text Available Arctic cyclone activity has a significant association with Arctic warming and Arctic ice decline. Cyclones in the North Pole are more complex and less developed than those in tropical regions. Identifying polar cyclones proves to be a task of greater complexity. To tackle this challenge, a new method which utilizes pressure level data and velocity field is proposed to improve the identification accuracy. In addition, the dynamic, simulative cyclone visualized with a 4D (four-dimensional wind field further validated the identification result. A knowledge-driven system is eventually constructed for visualizing and analyzing an atmospheric phenomenon (cyclone in the North Pole. The cyclone is simulated with WebGL on in a web environment using particle tracing. To achieve interactive frame rates, the graphics processing unit (GPU is used to accelerate the process of particle advection. It is concluded with the experimental results that: (1 the cyclone identification accuracy of the proposed method is 95.6% when compared with the NCEP/NCAR (National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis data; (2 the integrated knowledge-driven visualization system allows for streaming and rendering of millions of particles with an interactive frame rate to support knowledge discovery in the complex climate system of the Arctic region.

  12. Extreme warming in the NE Atlantic in the winter period 2002-2012 - an analysis with the regional atmospheric model COSMO-CLM and the Arctic System Reanalysis.

    Science.gov (United States)

    Kohnemann, Svenja; Heinemann, Guenther; Gutjahr, Oliver; Bromwich, David H.

    2016-04-01

    The high-resolution atmospheric model COSMO-CLM (CCLM, German Meteorological Service) is used to simulate the 2m-temperature and the boundary layer structures in the Arctic with focus on the NE Atlantic section the winter periods (Nov-Apr) between 2002 and 2015. The CCLM simulations have a horizontal resolution of 15 km for the whole Arctic. The comparable Arctic System Reanalysis data (ASR, Byrd Polar and Climate Research Center), which has been optimized for the Arctic, are available for the same time period with a horizontal resolution of 30 km. In addition, climatological data from Automatic Weather Stations (AWS) stations are used as verification. The comparison between the CCLM simulations and the ASR data shows a high agreement. Also the verification of both data sets with AWS and Era-Interim data shows a very high correlation for the air temperature. Slight differences between CCLM and ASR are recognizable in the extreme values as CCLM has the better ice information assimilated and the higher resolution during simulations. Time series of monthly mean based 2m-temperature indicate an enormous increase for the single months for the NE Atlantic and especially the region around the Siberian Island Novaya Zemlya. For example the CCLM March increase amounts up to 16 °C for the regional maximum for the period 2002-2012. The strong increase is mainly reducible to the decreasing sea ice situation in that region during the same time.

  13. Modulation of the Arctic Oscillation and the East Asian Winter Climate Relationships by the 11-year Solar Cycle

    Institute of Scientific and Technical Information of China (English)

    CHEN Wen; ZHOU Qun

    2012-01-01

    The modulation of the relationship between the Arctic Oscillation (AO) and the East Asian winter climate by the 11-year solar cycle was investigated.During winters with high solar activity (HS),robust warming appeared in northern Asia in a positive AO phase. This result corresponded to an enhanced anticyclonic flow at 850 hPa over northeastern Asia and a weakened East Asian trough (EAT) at 500 hPa.However,during winters with low solar activity (LS),both the surface warming and the intensities of the anticyclonic flow and the EAT were much less in the presence of a positive AO phase.The possible atmospheric processes for this 11-year solar-cycle modulation may be attributed to the indirect influence that solar activity induces in the structural changes of AO.During HS winters,the sea level pressure oscillation associated with the AO became stronger,with the significant influence of AO extending to East Asia.In the meantime,the AO-related zonal-mean zonal winds tended to extend more into the stratosphere during HS winters,which implies a stronger coupling to the stratosphere.These trends may have led to an enhanced AO phase difference; thus the associated East Asian climate anomalies became larger and more significant.The situation tended to reverse during LS winters.Further analyses revealed that the relationship between the winter AO and surface-climate anomalies in the following spring is also modulated by the 11-year solar cycle,with significant signals appearing only during HS phases.Solar-cycle variation should be taken into consideration when the AO is used to predict winter and spring climate anomalies over East Asia.

  14. Reconciliation of essential process parameters for an enhanced predictability of Arctic stratospheric ozone loss and its climate interactions

    Directory of Open Access Journals (Sweden)

    M. von Hobe

    2012-11-01

    Full Text Available Significant reductions in stratospheric ozone occur inside the polar vortices each spring when chlorine radicals produced by heterogeneous reactions on cold particle surfaces in winter destroy ozone mainly in two catalytic cycles, the ClO dimer cycle and the ClO/BrO cycle. Chlorofluorocarbons (CFCs, which are responsible for most of the chlorine currently present in the stratosphere, have been banned by the Montreal Protocol and its amendments, and the ozone layer is predicted to recover to 1980 levels within the next few decades. During the same period, however, climate change is expected to alter the temperature, circulation patterns and chemical composition in the stratosphere, and possible geo-engineering ventures to mitigate climate change may lead to additional changes. To realistically predict the response of the ozone layer to such influences requires the correct representation of all relevant processes. The European project RECONCILE has comprehensively addressed remaining questions in the context of polar ozone depletion, with the objective to quantify the rates of some of the most relevant, yet still uncertain physical and chemical processes. To this end RECONCILE used a broad approach of laboratory experiments, two field missions in the Arctic winter 2009/10 employing the high altitude research aircraft M55-Geophysica and an extensive match ozone sonde campaign, as well as microphysical and chemical transport modelling and data assimilation. Some of the main outcomes of RECONCILE are as follows: (1 vortex meteorology: the 2009/10 Arctic winter was unusually cold at stratospheric levels during the six-week period from mid-December 2009 until the end of January 2010, with reduced transport and mixing across the polar vortex edge; polar vortex stability and how it is influenced by dynamic processes in the troposphere has led to unprecedented, synoptic-scale stratospheric regions with temperatures below the frost point; in these regions

  15. Reconciliation of essential process parameters for an enhanced predictability of Arctic stratospheric ozone loss and its climate interactions

    Science.gov (United States)

    von Hobe, M.; Bekki, S.; Borrmann, S.; Cairo, F.; D'Amato, F.; Di Donfrancesco, G.; Dörnbrack, A.; Ebersoldt, A.; Ebert, M.; Emde, C.; Engel, I.; Ern, M.; Frey, W.; Griessbach, S.; Grooß, J.-U.; Gulde, T.; Günther, G.; Hösen, E.; Hoffmann, L.; Homonnai, V.; Hoyle, C. R.; Isaksen, I. S. A.; Jackson, D. R.; Jánosi, I. M.; Kandler, K.; Kalicinsky, C.; Keil, A.; Khaykin, S. M.; Khosrawi, F.; Kivi, R.; Kuttippurath, J.; Laube, J. C.; Lefèvre, F.; Lehmann, R.; Ludmann, S.; Luo, B. P.; Marchand, M.; Meyer, J.; Mitev, V.; Molleker, S.; Müller, R.; Oelhaf, H.; Olschewski, F.; Orsolini, Y.; Peter, T.; Pfeilsticker, K.; Piesch, C.; Pitts, M. C.; Poole, L. R.; Pope, F. D.; Ravegnani, F.; Rex, M.; Riese, M.; Röckmann, T.; Rognerud, B.; Roiger, A.; Rolf, C.; Santee, M. L.; Scheibe, M.; Schiller, C.; Schlager, H.; Siciliani de Cumis, M.; Sitnikov, N.; Søvde, O. A.; Spang, R.; Spelten, N.; Stordal, F.; Sumińska-Ebersoldt, O.; Viciani, S.; Volk, C. M.; vom Scheidt, M.; Ulanovski, A.; von der Gathen, P.; Walker, K.; Wegner, T.; Weigel, R.; Weinbuch, S.; Wetzel, G.; Wienhold, F. G.; Wintel, J.; Wohltmann, I.; Woiwode, W.; Young, I. A. K.; Yushkov, V.; Zobrist, B.; Stroh, F.

    2012-11-01

    Significant reductions in stratospheric ozone occur inside the polar vortices each spring when chlorine radicals produced by heterogeneous reactions on cold particle surfaces in winter destroy ozone mainly in two catalytic cycles, the ClO dimer cycle and the ClO/BrO cycle. Chlorofluorocarbons (CFCs), which are responsible for most of the chlorine currently present in the stratosphere, have been banned by the Montreal Protocol and its amendments, and the ozone layer is predicted to recover to 1980 levels within the next few decades. During the same period, however, climate change is expected to alter the temperature, circulation patterns and chemical composition in the stratosphere, and possible geo-engineering ventures to mitigate climate change may lead to additional changes. To realistically predict the response of the ozone layer to such influences requires the correct representation of all relevant processes. The European project RECONCILE has comprehensively addressed remaining questions in the context of polar ozone depletion, with the objective to quantify the rates of some of the most relevant, yet still uncertain physical and chemical processes. To this end RECONCILE used a broad approach of laboratory experiments, two field missions in the Arctic winter 2009/10 employing the high altitude research aircraft M55-Geophysica and an extensive match ozone sonde campaign, as well as microphysical and chemical transport modelling and data assimilation. Some of the main outcomes of RECONCILE are as follows: (1) vortex meteorology: the 2009/10 Arctic winter was unusually cold at stratospheric levels during the six-week period from mid-December 2009 until the end of January 2010, with reduced transport and mixing across the polar vortex edge; polar vortex stability and how it is influenced by dynamic processes in the troposphere has led to unprecedented, synoptic-scale stratospheric regions with temperatures below the frost point; in these regions stratospheric ice

  16. Reducing Spread in Climate Model Projections of a September Ice-Free Arctic

    Science.gov (United States)

    Liu, Jiping; Song, Mirong; Horton, Radley M.; Hu, Yongyun

    2013-01-01

    This paper addresses the specter of a September ice-free Arctic in the 21st century using newly available simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5). We find that large spread in the projected timing of the September ice-free Arctic in 30 CMIP5 models is associated at least as much with different atmospheric model components as with initial conditions. Here we reduce the spread in the timing of an ice-free state using two different approaches for the 30 CMIP5 models: (i) model selection based on the ability to reproduce the observed sea ice climatology and variability since 1979 and (ii) constrained estimation based on the strong and persistent relationship between present and future sea ice conditions. Results from the two approaches show good agreement. Under a high-emission scenario both approaches project that September ice extent will drop to approx. 1.7 million sq km in the mid 2040s and reach the ice-free state (defined as 1 million sq km) in 2054-2058. Under a medium-mitigation scenario, both approaches project a decrease to approx.1.7 million sq km in the early 2060s, followed by a leveling off in the ice extent.

  17. Abrupt Climate Change in the Arctic (and Beyond): An Update (Invited)

    Science.gov (United States)

    Alley, R. B.

    2013-12-01

    Our understanding of future Arctic change is informed by the history of past changes, which often have been both large and abrupt. The well-known ice-age events such as the Younger Dryas show how sea-ice changes can amplify forcing to produce very large responses, with wintertime sea ice especially important. These changes are increasingly seen to have played a central role in the ice-age cycling through their global impact on CO2 storage in the deep ocean. The Heinrich events reveal processes of ice-sheet/ocean interaction, some of which are being played out in Greenland and Antarctica now, and which may have large future effects on sea-level rise. The paleoclimatic record plus physical understanding greatly reduce the worst worries about instabilities from methane stored in cold places, but tend to support a role in amplifying future warming. Overall, the very large impacts of past Arctic changes, and the likelihood that future changes under business-as-usual fossil-fuel emissions will be unprecedented in combined size and speed, raise important questions.

  18. PCW/PHEOS-WCA: quasi-geostationary Arctic measurements for weather, climate, and air quality from highly eccentric orbits

    Science.gov (United States)

    Lachance, Richard L.; McConnell, John C.; McElroy, C. Tom; O'Neill, Norm; Nassar, Ray; Buijs, Henry; Rahnama, Peyman; Walker, Kaley; Martin, Randall; Sioris, Chris; Garand, Louis; Trichtchenko, Alexander; Bergeron, Martin

    2012-09-01

    The PCW (Polar Communications and Weather) mission is a dual satellite mission with each satellite in a highly eccentric orbit with apogee ~42,000 km and a period (to be decided) in the 12-24 hour range to deliver continuous communications and meteorological data over the Arctic and environs. Such as satellite duo can give 24×7 coverage over the Arctic. The operational meteorological instrument is a 21-channel spectral imager similar to the Advanced Baseline Imager (ABI). The PHEOS-WCA (weather, climate and air quality) mission is intended as an atmospheric science complement to the operational PCW mission. The target PHEOS-WCA instrument package considered optimal to meet the full suite of science team objectives consists of FTS and UVS imaging sounders with viewing range of ~4.5° or a Field of Regard (FoR) ~ 3400×3400 km2 from near apogee. The goal for the spatial resolution at apogee of each imaging sounder is 10×10 km2 or better and the goal for the image repeat time is targeted at ~2 hours or better. The FTS has 4 bands that span the MIR and NIR with a spectral resolution of 0.25 cm-1. They should provide vertical tropospheric profiles of temperature and water vapour in addition to partial columns of many other gases of interest for air quality. The two NIR bands target columns of CO2, CH4 and aerosol optical depth (OD). The UVS is an imaging spectrometer that covers the spectral range of 280-650 nm with 0.9 nm resolution and targets the tropospheric column densities of O3 and NO2 and several other Air Quality (AQ) gases as well the Aerosol Index (AI).

  19. How predictable is a summer-ice free Arctic?

    Science.gov (United States)

    Jahn, Alexandra

    2016-04-01

    There is large interest from different stakeholders in when we will first see a summer ice-free Arctic Ocean. However, while the CMIP5 models agree that we will see a further decline of the Arctic sea ice cover over the 21st century, their projections of when an ice-free Arctic will occur has a range of over 100 years for even the strongest forcing scenario, the RCP8.5. A large part of this uncertainty stems from model biases in the simulation of Arctic sea ice in some models. But apart from this bias, how predictable is the Arctic sea ice extent and the timing of the first ice-free Arctic summer in general? Using the Community Earth System Model (CESM) large ensemble with 40+ members for RCP8.5 and the CESM medium ensemble with 15 members for RCP4.5, we will show that internal variability leads to a range of ~20 years for predictions of threshold crossing of Arctic sea ice, limiting the long-term predictability of when an ice-free Arctic Ocean can first be expected. A detailed analysis of the trajectories of the individual ensemble members will reveal whether there are features of the climate system that allow an improvement of this predictability as we get closer to a summer ice-free Arctic.

  20. Climate Change and Arctic Response:Opportunities, Challenges and Risks%气候变化与北极响应--机遇、挑战与风险

    Institute of Scientific and Technical Information of China (English)

    杨孟倩; 葛珊珊; 张韧

    2016-01-01

    Based on research results on observed facts, trends and impact assessments about global climate change and the Arctic region response, this paper systematically analyzed and reviewed the spatial and temporal distribution, trends, meteorological, hydrological and geographic factors, pathways and mechanisms that affect the ecological environment of Arctic sea ice in the background of global climate change. We analyzed that the ice melting made oil and gas in theArctic, development of mineral resources, and the expected impact on Arctic navigation and shipping of the channel pattern of maritime strategy, opportunities, challenges and risks. And it puts forward some suggestions about our government participating in Arctic affairs, planning to use of Arctic waterways and Arctic interests of the game to respond to Arctic circumpolar countries for strategy.%基于全球气候变化与北极区域响应的观测事实、趋势预测和影响评估等国内外研究成果,较为系统地分析、评述了全球气候变化背景下,北极海冰的时空分布特征、变化趋势及其对气象、水文要素和地理形态、生态环境的影响途径和机理;分析了冰雪融化对北极油气、矿藏资源开发、北极通航预期及对我国海上战略通道和航运格局的影响、机遇、挑战和风险;针对环北极国家的北极战略,提出了我国参与北极事务、规划利用北极航道和北极利益博弈的对策建议。

  1. Ice-Free Arctic Ocean?

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    The current warming trends in the Arctic may shove the Arctic system into a seasonally ice-free state not seen for more than one million years, according to a new report. The melting is accelerating, and researchers were unable to identify any natural processes that might slow the deicing of the Arctic. "What really makes the Arctic different…

  2. The influence of Holocene climate and catchment ontogeny on organic carbon cycling in low-Arctic lakes of SW Greenland

    Science.gov (United States)

    Leng, Melanie; Anderson, N. John

    2014-05-01

    Arctic soils represent a major store of organic carbon which is now under threat from regional warming. While much of the carbon is mineralized and released directly to the atmosphere as CO2, some is moved laterally as dissolved and particulate organic C into streams and lakes where it fuels microbial processes and is degassed, some however is buried in lake sediments, where it is effectively removed from the terrestrial C cycle. It is possible to consider how catchment-lake C interactions have varied under natural climate variability and soil/vegetation development by using lake sediment records. Here we present Holocene organic C concentration and isotope data (TOC, C/N, δ13C) from a series of small lakes along Kangerlussuaq (coast to ice cap margin), southwest Greenland, a transect that covers a natural climate gradient and range of limnological conditions. Most Arctic lakes, including those in coastal west Greenland are considered to be net heterotrophic (ecosystem respiration is greater than primary production), i.e. they are net CO2 sources. However, there is evidence that some of the inland Kangerlussuaq lakes are autotrophic. The coastal lakes formed c. 11 cal. ka BP following initial retreat of the ice sheet margin while the inland lakes formed between 8-7 ka BP after its rapid retreat eastwards. The sediment C isotope data suggest a complex Holocene history of interactions between the lakes and their catchments, reflecting glacial retreat, soil and vegetation development and climate-driven hydrological change that had a strong influence on transfer of terrestrially-derived carbon from land to water. At the coast, after 8.5 cal. ka BP, soil development and associated vegetation processes began to exert a strong control on terrestrial-aquatic C-cycling. This is not seen in the inland lakes until ca. 5 ka BP with the maximum extent of dwarf shrub tundra. Some of the lakes respond to Neoglacial cooling from around 5-4 cal. ka BP, when there was a change in

  3. Management system, organizational climate and performance relationships

    Science.gov (United States)

    Davis, B. D.

    1979-01-01

    Seven aerospace firms were investigated to determine if a relationship existed among management systems, organizational climate, and organization performance. Positive relationships were found between each of these variables, but a statistically significant relationship existed only between the management system and organizational climate. The direction and amount of communication and the degree of decentralized decision-making, elements of the management system, also had a statistically significant realtionship with organization performance.

  4. Consequences of future increased Arctic runoff on Arctic Ocean stratification, circulation, and sea ice cover

    Science.gov (United States)

    Nummelin, Aleksi; Ilicak, Mehmet; Li, Camille; Smedsrud, Lars H.

    2016-01-01

    The Arctic Ocean has important freshwater sources including river runoff, low evaporation, and exchange with the Pacific Ocean. In the future, we expect even larger freshwater input as the global hydrological cycle accelerates, increasing high-latitude precipitation, and river runoff. Previous modeling studies show some robust responses to high-latitude freshwater perturbations, including a strengthening of Arctic stratification and a weakening of the large-scale ocean circulation; some idealized modeling studies also document a stronger cyclonic circulation within the Arctic Ocean itself. With the broad range of scales and processes involved, the overall effect of increasing runoff requires an understanding of both the local processes and the broader linkages between the Arctic and surrounding oceans. Here we adopt a more comprehensive modeling approach by increasing river runoff to the Arctic Ocean in a coupled ice-ocean general circulation model, and show contrasting responses in the polar and subpolar regions. Within the Arctic, the stratification strengthens, the halocline and Atlantic Water layer warm, and the cyclonic circulation spins up, in agreement with previous work. In the subpolar North Atlantic, the model simulates a colder and fresher water column with weaker barotropic circulation. In contrast to the estuarine circulation theory, the volume exchange between the Arctic Ocean and the surrounding oceans does not increase with increasing runoff. While these results are robust in our model, we require experiments with other model systems and more complete observational syntheses to better constrain the sensitivity of the climate system to high-latitude freshwater perturbations.

  5. Beyond Thin Ice: Co-Communicating the Many Arctics

    Science.gov (United States)

    Druckenmiller, M. L.; Francis, J. A.; Huntington, H.

    2015-12-01

    Science communication, typically defined as informing non-expert communities of societally relevant science, is persuaded by the magnitude and pace of scientific discoveries, as well as the urgency of societal issues wherein science may inform decisions. Perhaps nowhere is the connection between these facets stronger than in the marine and coastal Arctic where environmental change is driving advancements in our understanding of natural and socio-ecological systems while paving the way for a new assortment of arctic stakeholders, who generally lack adequate operational knowledge. As such, the Arctic provides opportunity to advance the role of science communication into a collaborative process of engagement and co-communication. To date, the communication of arctic change falls within four primary genres, each with particular audiences in mind. The New Arctic communicates an arctic of new stakeholders scampering to take advantage of unprecedented access. The Global Arctic conveys the Arctic's importance to the rest of the world, primarily as a regulator of lower-latitude climate and weather. The Intra-connected Arctic emphasizes the increasing awareness of the interplay between system components, such as between sea ice loss and marine food webs. The Transforming Arctic communicates the region's trajectory relative to the historical Arctic, acknowledging the impacts on indigenous peoples. The broad societal consensus on climate change in the Arctic as compared to other regions in the world underscores the opportunity for co-communication. Seizing this opportunity requires the science community's engagement with stakeholders and indigenous peoples to construct environmental change narratives that are meaningful to climate responses relative to non-ecological priorities (e.g., infrastructure, food availability, employment, or language). Co-communication fosters opportunities for new methods of and audiences for communication, the co-production of new interdisciplinary

  6. Energy fluxes in a high Arctic tundra heath subjected to strong climate warming

    Science.gov (United States)

    Lund, M.; Hansen, B. U.; Pedersen, S. H.; Stiegler, C.; Tamstorf, M. P.

    2012-12-01

    During recent decades the observed warming in the Arctic has been almost twice as large as the global average. The implications of such strong warming on surface energy balance, regulating permafrost thaw, hydrology, soil stability and carbon mineralization, need to be assessed. In Zackenberg, northeast Greenland, measurements of energy balance components in various environments have been performed since late 90's, coordinated by Zackenberg Ecological Research Operations. During 1996-2009, mean annual temperature in the area has increased by ca. 0.15 °C yr-1; while maximum thaw depth has increased by 1.4-1.8 cm yr-1. Eddy covariance measurements of energy fluxes have been performed in a Cassiope heath plant community, a commonly occurring tundra ecosystem type in circumpolar middle and high Arctic areas, in Zackenberg allowing for detailed investigations of relationships between energy fluxes and meteorological and soil physical characteristics. As the available data set spans more than a decade, possible trends in energy flux components resulting from warming related changes such as earlier snow melt, increased active layer depth and higher temperatures can be investigated. This presentation will focus on the mid-summer period from which eddy covariance measurements are available. The summer-time energy partitioning at the Zackenberg tundra heath site will be characterized using ratios of sensible, latent and ground heat flux to net radiation and Bowen ratio, whereas the surface characteristics will be described using surface resistance, McNaughton and Jarvis Ω value and Priestley-Taylor α coefficient. Furthermore, we aim to estimate the full year, all energy balance components for the tundra heath site using Snow Model (Liston and Elder 2006) for the dark winter period during which no eddy covariance measurements are available. The snow cover duration in the area is a major regulator of the energy partitioning. Early results point towards high summer

  7. Atmospheric HCH concentrations over the Marine Boundary Layer from Shanghai, China to the Arctic Ocean: role of human activity and climate change.

    Science.gov (United States)

    Wu, Xiaoguo; Lam, James C W; Xia, Chonghuan; Kang, Hui; Sun, Liguang; Xie, Zhouqing; Lam, Paul K S

    2010-11-15

    From July to September 2008, air samples were collected aboard the research expedition icebreaker XueLong (Snow Dragon) as part of the 2008 Chinese Arctic Research Expedition Program. Hexachlorocyclohexane (HCH) concentrations were analyzed in all of the samples. The average concentrations (± standard deviation) over the entire period were 33 ± 16, 5.4 ± 3.0, and 13 ± 7.5 pg m⁻³ for α-, β- and γ-HCH, respectively. Compared to previous studies in the same areas, total HCH (ΣHCH, the sum of α-, β-, and γ-HCH) levels declined by more than 10 × compared to those observed in the 1990s, but were approximately 4 × higher than those measured by the 2003 China Arctic Research Expedition, suggesting the increase of atmospheric ΣHCH recently. Because of the continuing use of lindane, ratios of α/γ-HCH showed an obvious decrease in North Pacific and Arctic region compared with those for 2003 Chinese Arctic Research Expedition. In Arctic, the level of α-HCH was found to be linked to sea ice distribution. Geographically, the average concentration of α-HCH in air samples from the Chukchi and Beaufort Seas, neither of which contain sea ice, was 23 ± 4.4 pg m⁻³, while samples from the area covered by seasonal ice (∼75°N to ∼83°N), the so-called "floating sea ice region", contained the highest average levels of α-HCH at 48 ± 12 pg m⁻³, likely due to emission from sea ice and strong air-sea exchange. The lowest concentrations of α-HCH were observed in the pack ice region in the high Arctic covered by multiyear sea ice (∼83°N to ∼86°N). This phenomenon implies that the re-emission of HCH trapped in ice sheets and Arctic Ocean may accelerate during the summer as ice coverage in the Arctic Ocean decreases in response to global climate change.

  8. Limitations of a coupled regional climate model in the reproduction of the observed Arctic sea-ice retreat

    Directory of Open Access Journals (Sweden)

    W. Dorn

    2012-03-01

    Full Text Available The effects of internal model variability on the simulation of Arctic sea-ice extent and volume have been examined with the aid of a seven-member ensemble with a coupled regional climate model for the period 1948–2008. Beyond general weaknesses related to insufficient representation of feedback processes, it is found that the model's ability to reproduce observed summer sea-ice retreat depends mainly on two factors: the correct simulation of the atmospheric circulation during the summer months and the sea-ice volume at the beginning of the melting period. Since internal model variability shows its maximum during the summer months, the ability to reproduce the observed atmospheric summer circulation is limited. In addition, the atmospheric circulation during summer also significantly affects the sea-ice volume over the years, leading to a limited ability to start with reasonable sea-ice volume into the melting period. Furthermore, the sea-ice volume pathway shows notable decadal variability which amplitude varies among the ensemble members. The scatter is particularly large in periods when the ice volume increases, indicating limited skill in reproducing high-ice years.

  9. An Arctic source for the Great Salinity Anomaly - A simulation of the Arctic ice-ocean system for 1955-1975

    Science.gov (United States)

    Hakkinen, Sirpa

    1993-01-01

    The paper employs a fully prognostic Arctic ice-ocean model to study the interannual variability of sea ice during the period 1955-1975 and to explain the large variability of the ice extent in the Greenland and Iceland seas during the late 1960s. The model is used to test the contention of Aagaard and Carmack (1989) that the Great Salinity Anomaly (GSA) was a consequence of the anomalously large ice export in 1968. The high-latitude ice-ocean circulation changes due to wind field changes are explored. The ice export event of 1968 was the largest in the simulation, being about twice as large as the average and corresponding to 1600 cu km of excess fresh water. The simulations suggest that, besides the above average ice export to the Greenland Sea, there was also fresh water export to support the larger than average ice cover. The model results show the origin of the GSA to be in the Arctic, and support the view that the Arctic may play an active role in climate change.

  10. Threshold sensitivity of shallow Arctic lakes and sublake permafrost to changing winter climate

    Science.gov (United States)

    Arp, Christopher D.; Jones, Benjamin M.; Grosse, Guido; Bondurant, Allen C.; Romanovksy, Vladimir E.; Hinkel, Kenneth M.; Parsekian, Andrew D.

    2016-01-01

    Interactions and feedbacks between abundant surface waters and permafrost fundamentally shape lowland Arctic landscapes. Sublake permafrost is maintained when the maximum ice thickness (MIT) exceeds lake depth and mean annual bed temperatures (MABTs) remain below freezing. However, declining MIT since the 1970s is likely causing talik development below shallow lakes. Here we show high-temperature sensitivity to winter ice growth at the water-sediment interface of shallow lakes based on year-round lake sensor data. Empirical model experiments suggest that shallow (1 m depth) lakes have warmed substantially over the last 30 years (2.4°C), with MABT above freezing 5 of the last 7 years. This is in comparison to slower rates of warming in deeper (3 m) lakes (0.9°C), with already well-developed taliks. Our findings indicate that permafrost below shallow lakes has already begun crossing a critical thawing threshold approximately 70 years prior to predicted terrestrial permafrost thaw in northern Alaska.

  11. Past climate-driven range shifts and population genetic diversity in arctic plants

    DEFF Research Database (Denmark)

    Pellissier, Loïc; Eidesen, Pernille Bronken; Ehrich, Dorothee

    2016-01-01

    High intra-specific genetic diversity is necessary for species adaptation to novel environments under climate change, but species tracking suitable conditions are losing alleles through successive founder events during range shift. Here, we investigated the relationship between range shift since ...

  12. Using next-generation sequencing for molecular reconstruction of past Arctic vegetation and climate

    DEFF Research Database (Denmark)

    Sønstebø, J H; Gielly, L; Brysting, A K

    2010-01-01

    Palaeoenvironments and former climates are typically inferred from pollen and macrofossil records. This approach is time-consuming and suffers from low taxonomic resolution and biased taxon sampling. Here, we test an alternative DNA-based approach utilizing the P6 loop in the chloroplast trnL (UA...

  13. Human-induced Arctic moistening.

    Science.gov (United States)

    Min, Seung-Ki; Zhang, Xuebin; Zwiers, Francis

    2008-04-25

    The Arctic and northern subpolar regions are critical for climate change. Ice-albedo feedback amplifies warming in the Arctic, and fluctuations of regional fresh water inflow to the Arctic Ocean modulate the deep ocean circulation and thus exert a strong global influence. By comparing observations to simulations from 22 coupled climate models, we find influence from anthropogenic greenhouse gases and sulfate aerosols in the space-time pattern of precipitation change over high-latitude land areas north of 55 degrees N during the second half of the 20th century. The human-induced Arctic moistening is consistent with observed increases in Arctic river discharge and freshening of Arctic water masses. This result provides new evidence that human activity has contributed to Arctic hydrological change.

  14. Performance of municipal waste stabilization ponds in the Canadian Arctic

    DEFF Research Database (Denmark)

    Ragush, Colin M.; Schmidt, Jordan J.; Krkosek, Wendy H.

    2015-01-01

    The majority of small remote communities in the Canadian arctic territory of Nunavut utilize waste stabilization ponds (WSPs) for municipal wastewater treatment because of their relatively low capital and operational costs, and minimal complexity. New national effluent quality regulations have been...... implemented in Canada, but not yet applied to Canada’s Arctic due to uncertainty related to the performance of current wastewater treatment systems. Waste stabilization pond (WSP) treatment performance is impacted by community water use, pond design, and climate. The greatest challenge arctic communities...

  15. Climate Model Diagnostic Analyzer Web Service System

    Science.gov (United States)

    Lee, S.; Pan, L.; Zhai, C.; Tang, B.; Kubar, T. L.; Li, J.; Zhang, J.; Wang, W.

    2015-12-01

    Both the National Research Council Decadal Survey and the latest Intergovernmental Panel on Climate Change Assessment Report stressed the need for the comprehensive and innovative evaluation of climate models with the synergistic use of global satellite observations in order to improve our weather and climate simulation and prediction capabilities. The abundance of satellite observations for fundamental climate parameters and the availability of coordinated model outputs from CMIP5 for the same parameters offer a great opportunity to understand and diagnose model biases in climate models. In addition, the Obs4MIPs efforts have created several key global observational datasets that are readily usable for model evaluations. However, a model diagnostic evaluation process requires physics-based multi-variable comparisons that typically involve large-volume and heterogeneous datasets, making them both computationally- and data-intensive. In response, we have developed a novel methodology to diagnose model biases in contemporary climate models and implementing the methodology as a web-service based, cloud-enabled, provenance-supported climate-model evaluation system. The evaluation system is named Climate Model Diagnostic Analyzer (CMDA), which is the product of the research and technology development investments of several current and past NASA ROSES programs. The current technologies and infrastructure of CMDA are designed and selected to address several technical challenges that the Earth science modeling and model analysis community faces in evaluating and diagnosing climate models. In particular, we have three key technology components: (1) diagnostic analysis methodology; (2) web-service based, cloud-enabled technology; (3) provenance-supported technology. The diagnostic analysis methodology includes random forest feature importance ranking, conditional probability distribution function, conditional sampling, and time-lagged correlation map. We have implemented the

  16. Arctic Rabies – A Review

    Directory of Open Access Journals (Sweden)

    Prestrud Pål

    2004-03-01

    Full Text Available Rabies seems to persist throughout most arctic regions, and the northern parts of Norway, Sweden and Finland, is the only part of the Arctic where rabies has not been diagnosed in recent time. The arctic fox is the main host, and the same arctic virus variant seems to infect the arctic fox throughout the range of this species. The epidemiology of rabies seems to have certain common characteristics in arctic regions, but main questions such as the maintenance and spread of the disease remains largely unknown. The virus has spread and initiated new epidemics also in other species such as the red fox and the racoon dog. Large land areas and cold climate complicate the control of the disease, but experimental oral vaccination of arctic foxes has been successful. This article summarises the current knowledge and the typical characteristics of arctic rabies including its distribution and epidemiology.

  17. AMAP Assessment 2013: Arctic Ocean acidification

    Science.gov (United States)

    2013-01-01

    This assessment report presents the results of the 2013 AMAP Assessment of Arctic Ocean Acidification (AOA). This is the first such assessment dealing with AOA from an Arctic-wide perspective, and complements several assessments that AMAP has delivered over the past ten years concerning the effects of climate change on Arctic ecosystems and people. The Arctic Monitoring and Assessment Programme (AMAP) is a group working under the Arctic Council. The Arctic Council Ministers have requested AMAP to: - produce integrated assessment reports on the status and trends of the conditions of the Arctic ecosystems;

  18. Late Cenozoic Paleoceanography of the Central Arctic Ocean

    Energy Technology Data Exchange (ETDEWEB)

    O' Regan, Matt, E-mail: oreganM1@cardiff.ac.uk [School of Earth and Ocean Sciences, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Wales (United Kingdom)

    2011-05-15

    The Arctic Ocean is the smallest and perhaps least accessible of the worlds oceans. It occupies only 26% of the global ocean area, and less than 10% of its volume. However, it exerts a disproportionately large influence on the global climate system through a complex set of positive and negative feedback mechanisms directly or indirectly related to terrestrial ice and snow cover and sea ice. Increasingly, the northern high latitude cryosphere is seen as an exceptionally fragile part of the global climate system, a fact exemplified by observed reductions in sea ice extent during the past decades [2]. The paleoceanographic evolution of the Arctic Ocean can provide important insights into the physical forcing mechanisms that affect the form, intensity and permanence of ice in the high Arctic, and its sensitivity to these mechanisms in vastly different climate states of the past. However, marine records capturing the late Cenozoic paleoceanography of the Arctic are limited - most notably because only a single deep borehole exists from the central parts of this Ocean. This paper reviews the principal late Cenozoic (Neogene/Quaternary) results from the Arctic Coring Expedition to the Lomonosov Ridge and in light of recent data and observations on modern sea ice, outlines emerging questions related to three main themes: 1) the establishment of the 'modern' Arctic Ocean and the opening of the Fram Strait 2) the inception of perennial sea ice 3) The Quaternary intensification of Northern Hemisphere glaciations.

  19. TOPAZ4: an ocean-sea ice data assimilation system for the North Atlantic and Arctic

    Directory of Open Access Journals (Sweden)

    P. Sakov

    2012-08-01

    Full Text Available We present a detailed description of TOPAZ4, the latest version of TOPAZ – a coupled ocean-sea ice data assimilation system for the North Atlantic Ocean and Arctic. It is the only operational, large-scale ocean data assimilation system that uses the ensemble Kalman filter. This means that TOPAZ features a time-evolving, state-dependent estimate of the state error covariance. Based on results from the pilot MyOcean reanalysis for 2003–2008, we demonstrate that TOPAZ4 produces a realistic estimate of the ocean circulation in the North Atlantic and the sea-ice variability in the Arctic. We find that the ensemble spread for temperature and sea-level remains fairly constant throughout the reanalysis demonstrating that the data assimilation system is robust to ensemble collapse. Moreover, the ensemble spread for ice concentration is well correlated with the actual errors. This indicates that the ensemble statistics provide reliable state-dependent error estimates – a feature that is unique to ensemble-based data assimilation systems. We demonstrate that the quality of the reanalysis changes when different sea surface temperature products are assimilated, or when in-situ profiles below the ice in the Arctic Ocean are assimilated. We find that data assimilation improves the match to independent observations compared to a free model. Improvements are particularly noticeable for ice thickness, salinity in the Arctic, and temperature in the Fram Strait, but not for transport estimates or underwater temperature. At the same time, the pilot reanalysis has revealed several flaws in the system that have degraded its performance. Finally, we show that a simple bias estimation scheme can effectively detect the seasonal or constant bias in temperature and sea-level.

  20. Simulation of Extreme Arctic Cyclones in IPCC AR5 Experiments

    Science.gov (United States)

    Vavrus, S. J.

    2012-12-01

    Although impending Arctic climate change is widely recognized, a wild card in its expression is how extreme weather events in this region will respond to greenhouse warming. Intense polar cyclones represent one type of high-latitude phenomena falling into this category, including very deep synoptic-scale cyclones and mesoscale polar lows. These systems inflict damage through high winds, heavy precipitation, and wave action along coastlines, and their impact is expected to expand in the future, when reduced sea ice cover allows enhanced wave energy. The loss of a buffering ice pack could greatly increase the rate of coastal erosion, which has already been increasing in the Arctic. These and related threats may amplify if extreme Arctic cyclones become more frequent and/or intense in a warming climate with much more open water to fuel them. This possibility has merit on the basis of GCM experiments, which project that greenhouse forcing causes lower mean sea level pressure (SLP) in the Arctic and a strengthening of the deepest storms over boreal high latitudes. In this study, the latest Coupled Model Intercomparison Project (CMIP5) climate model output is used to investigate the following questions: (1) What are the spatial and seasonal characteristics of extreme Arctic cyclones? (2) How well do GCMs simulate these phenomena? (3) Are Arctic cyclones already showing the expected response to greenhouse warming in climate models? To address these questions, a retrospective analysis is conducted of the transient 20th century simulations among the CMIP5 GCMs (spanning years 1850-2005). The results demonstrate that GCMs are able to reasonably represent extreme Arctic cyclones and that the simulated characteristics do not depend significantly on model resolution. Consistent with observational evidence, climate models generate these storms primarily during winter and within the climatological Aleutian and Icelandic Low regions. Occasionally the cyclones remain very intense

  1. The Community Climate System Model: CCSM3

    Energy Technology Data Exchange (ETDEWEB)

    Collins, W D; Blackmon, M; Bitz, C; Bonan, G; Bretherton, C S; Carton, J A; Chang, P; Doney, S; Hack, J J; Kiehl, J T; Henderson, T; Large, W G; McKenna, D; Santer, B D; Smith, R D

    2004-12-27

    A new version of the Community Climate System Model (CCSM) has been developed and released to the climate community. CCSM3 is a coupled climate model with components representing the atmosphere, ocean, sea ice, and land surface connected by a flux coupler. CCSM3 is designed to produce realistic simulations over a wide range of spatial resolutions, enabling inexpensive simulations lasting several millennia or detailed studies of continental-scale climate change. This paper will show results from the configuration used for climate-change simulations with a T85 grid for atmosphere and land and a 1-degree grid for ocean and sea-ice. The new system incorporates several significant improvements in the scientific formulation. The enhancements in the model physics are designed to reduce or eliminate several systematic biases in the mean climate produced by previous editions of CCSM. These include new treatments of cloud processes, aerosol radiative forcing, land-atmosphere fluxes, ocean mixed-layer processes, and sea-ice dynamics. There are significant improvements in the sea-ice thickness, polar radiation budgets, equatorial sea-surface temperatures, ocean currents, cloud radiative effects, and ENSO teleconnections. CCSM3 can produce stable climate simulations of millenial duration without ad hoc adjustments to the fluxes exchanged among the component models. Nonetheless, there are still systematic biases in the ocean-atmosphere fluxes in western coastal regions, the spectrum of ENSO variability, the spatial distribution of precipitation in the Pacific and Indian Oceans, and the continental precipitation and surface air temperatures. We conclude with the prospects for extending CCSM to a more comprehensive model of the Earth's climate system.

  2. Climate change impacts on food system

    Science.gov (United States)

    Zhang, X.; Cai, X.; Zhu, T.

    2014-12-01

    Food system includes biophysical factors (climate, land and water), human environments (production technologies and food consumption, distribution and marketing), as well as the dynamic interactions within them. Climate change affects agriculture and food systems in various ways. Agricultural production can be influenced directly by climatic factors such as mean temperature rising, change in rainfall patterns, and more frequent extreme events. Eventually, climate change could cause shift of arable land, alteration of water availability, abnormal fluctuation of food prices, and increase of people at risk of malnutrition. This work aims to evaluate how climate change would affect agricultural production biophysically and how these effects would propagate to social factors at the global level. In order to model the complex interactions between the natural and social components, a Global Optimization model of Agricultural Land and Water resources (GOALW) is applied to the analysis. GOALW includes various demands of human society (food, feed, other), explicit production module, and irrigation water availability constraint. The objective of GOALW is to maximize global social welfare (consumers' surplus and producers' surplus).Crop-wise irrigation water use in different regions around the world are determined by the model; marginal value of water (MVW) can be obtained from the model, which implies how much additional welfare benefit could be gained with one unit increase in local water availability. Using GOALW, we will analyze two questions in this presentation: 1) how climate change will alter irrigation requirements and how the social system would buffer that by price/demand adjustment; 2) how will the MVW be affected by climate change and what are the controlling factors. These results facilitate meaningful insights for investment and adaptation strategies in sustaining world's food security under climate change.

  3. The Svalbard REU Program: A High-Latitude Undergraduate Research Program in Glacial, Fluvial and Marine Processes Relevant to Arctic Climate Change

    Science.gov (United States)

    Powell, R.; Brigham-Grette, J.; Cumpston, R.; Trusel, L.; Werner, A.; Roof, S.; Retelle, M.

    2005-12-01

    A pilot-study field season was conducted this past summer from the most northerly permanent settlement in the world as part of our ongoing Svalbard REU program funded by the National Science Foundation (award OPP-0244097). Ny Alesund, on the island of Spitsbergen, Svalbard, is an international research center operated by Norway, and during summers, hosts about 100 scientists from over 15 nations. With NSF support, the US now participates in a new marine laboratory that opened this year, and we made that our operations center. The success of our field program is enhanced by tight logistics and research objectives integrated with UNIS (the University Centre on Svalbard), the Norwegian Polar Institute and Kings Bay AS. Our program provides genuine research experiences in Arctic Quaternary science for undergraduates. Research focuses on modern glacial sedimentation processes relevant to understanding records of past climate changes preserved in marine and lacustrine basins. Students in this marine portion of the program had a total immersion experience, being surrounded by scientists from different nations and from disciplines differing widely from theirs. They interacted with these scientists formally and informally, discussing their science plans, attending weekly science talks, and enjoying conversations at meal times. First, we introduced the students to arctic glacial and marine systems, and then through discussion and demonstration they developed their own research plans and made decisions on modifying sampling schemes through the field season. Studies focused on sediment transport and deposition in Kongsfjorden by polythermal tidewater glaciers, icebergs, meltwater streams and marine currents. Students sampled glaciers and icebergs for debris concentrations, collected seawater samples for suspended sediment concentrations, performed CTD casts to define water column structure, conducted bathymetric profiling using GPS control, and collected fjord sediment samples

  4. Arctic Ocean Scientific Drilling: The Next Frontier

    Directory of Open Access Journals (Sweden)

    Ruediger Stein

    2010-04-01

    Full Text Available The modern Arctic Ocean appears to be changing faster than any other region on Earth. To understand the potential extent of high latitude climate change, it is necessary to sample the history stored in the sediments filling the basins and covering the ridges of the Arctic Ocean. These sediments have been imaged with seismic reflection data, but except for the superficial record, which has been piston cored, they have been sampled only on the Lomonosov Ridge in 2004 during the Arctic Coring Expedition (ACEX-IODP Leg 302; Backman et al., 2006 and in 1993 in the ice-free waters in the Fram Strait/Yermak Plateau area (ODP Leg 151; Thiede et al., 1996.Although major progress in Arctic Ocean research has been made during the last few decades, the short- and long-term paleoceanographic and paleoclimatic history as well as its plate-tectonic evolution are poorly known compared to the other oceans. Despite the importance of the Arctic in the climate system, the database we have from this area is still very weak. Large segments of geologic time have not been sampled in sedimentary sections. The question of regional variations cannot be addressed.

  5. Processes and impacts of Arctic amplification: A research synthesis

    Science.gov (United States)

    Serreze, Mark C.; Barry, Roger G.

    2011-05-01

    The past decade has seen substantial advances in understanding Arctic amplification — that trends and variability in surface air temperature tend to be larger in the Arctic region than for the Northern Hemisphere or globe as a whole. We provide a synthesis of research on Arctic amplification, starting with a historical context and then addressing recent insights into processes and key impacts, based on analysis of the instrumental record, modeling studies, and paleoclimate reconstructions. Arctic amplification is now recognized as an inherent characteristic of the global climate system, with multiple intertwined causes operating on a spectrum of spatial and temporal scales. These include, but are not limited to, changes in sea ice extent that impact heat fluxes between the ocean and the atmosphere, atmospheric and oceanic heat transports, cloud cover and water vapor that alter the longwave radiation flux to the surface, soot on snow and heightened black carbon aerosol concentrations. Strong warming over the Arctic Ocean during the past decade in autumn and winter, clearly associated with reduced sea ice extent, is but the most recent manifestation of the phenomenon. Indeed, periods of Arctic amplification are evident from analysis of both warm and cool periods over at least the past three million years. Arctic amplification being observed today is expected to become stronger in coming decades, invoking changes in atmospheric circulation, vegetation and the carbon cycle, with impacts both within and beyond the Arctic.

  6. Arctic Glass: Innovative Consumer Technology in Support of Arctic Research

    Science.gov (United States)

    Ruthkoski, T.

    2015-12-01

    The advancement of cyberinfrastructure on the North Slope of Alaska is drastically limited by location-specific conditions, including: unique geophysical features, remoteness of location, and harsh climate. The associated cost of maintaining this unique cyberinfrastructure also becomes a limiting factor. As a result, field experiments conducted in this region have historically been at a technological disadvantage. The Arctic Glass project explored a variety of scenarios where innovative consumer-grade technology was leveraged as a lightweight, rapidly deployable, sustainable, alternatives to traditional large-scale Arctic cyberinfrastructure installations. Google Glass, cloud computing services, Internet of Things (IoT) microcontrollers, miniature LIDAR, co2 sensors designed for HVAC systems, and portable network kits are several of the components field-tested at the Toolik Field Station as part of this project. Region-specific software was also developed, including a multi featured, voice controlled Google Glass application named "Arctic Glass". Additionally, real-time sensor monitoring and remote control capability was evaluated through the deployment of a small cluster of microcontroller devices. Network robustness was analyzed as the devices delivered streams of abiotic data to a web-based dashboard monitoring service in near real time. The same data was also uploaded synchronously by the devices to Amazon Web Services. A detailed overview of solutions deployed during the 2015 field season, results from experiments utilizing consumer sensors, and potential roles consumer technology could play in support of Arctic science will be discussed.

  7. Changing Arctic ecosystems: ecology of loons in a changing Arctic

    Science.gov (United States)

    Uher-Koch, Brian; Schmutz, Joel; Whalen, Mary; Pearce, John M.

    2014-01-01

    The U.S. Geological Survey (USGS) Changing Arctic Ecosystems (CAE) initiative informs key resource management decisions for Arctic Alaska by providing scientific information on current and future ecosystem response to a changing climate. From 2010 to 2014, a key study area for the USGS CAE initiative has been the Arctic Coastal Plain of northern Alaska. This region has experienced rapid warming during the past 30 years, leading to the thawing of permafrost and changes to lake and river systems. These changes, and projections of continued change, have raised questions about effects on wildlife populations that rely on northern lake ecosystems, such as loons. Loons rely on freshwater lakes for nesting habitat and the fish and invertebrates inhabiting the lakes for food. Loons live within the National Petroleum Reserve-Alaska (NPR-A) on Alaska’s northern coast, where oil and gas development is expected to increase. Research by the USGS examines how breeding loons use the Arctic lake ecosystem and the capacity of loons to adapt to future landscape change.

  8. Observing the carbon-climate system

    CERN Document Server

    Schimel, David; Moore, Berrien; Chatterjee, Abhishek; Baker, David; Berry, Joe; Bowman, Kevin; Crisp, Phillipe Ciais David; Crowell, Sean; Denning, Scott; Duren, Riley; Friedlingstein, Pierre; Gierach, Michelle; Gurney, Kevin; Hibbard, Kathy; Houghton, Richard A; Huntzinger, Deborah; Hurtt, George; Jucks, Ken; Kawa, Randy; Koster, Randy; Koven, Charles; Luo, Yiqi; Masek, Jeff; McKinley, Galen; Miller, Charles; Miller, John; Moorcroft, Paul; Nassar, Ray; ODell, Chris; Ott, Leslie; Pawson, Steven; Puma, Michael; Quaife, Tristan; Riris, Haris; Romanou, Anastasia; Rousseaux, Cecile; Schuh, Andrew; Shevliakova, Elena; Tucker, Compton; Wang, Ying Ping; Williams, Christopher; Xiao, Xiangming; Yokota, Tatsuya

    2016-01-01

    Increases in atmospheric CO2 and CH4 result from a combination of forcing from anthropogenic emissions and Earth System feedbacks that reduce or amplify the effects of those emissions on atmospheric concentrations. Despite decades of research carbon-climate feedbacks remain poorly quantified. The impact of these uncertainties on future climate are of increasing concern, especially in the wake of recent climate negotiations. Emissions, long concentrated in the developed world, are now shifting to developing countries, where the emissions inventories have larger uncertainties. The fraction of anthropogenic CO2 remaining in the atmosphere has remained remarkably constant over the last 50 years. Will this change in the future as the climate evolves? Concentrations of CH4, the 2nd most important greenhouse gas, which had apparently stabilized, have recently resumed their increase, but the exact cause for this is unknown. While greenhouse gases affect the global atmosphere, their sources and sinks are remarkably he...

  9. The Impact of Climate Change on Microbial Communities and Carbon Cycling in High Arctic Permafrost Soil from Spitsbergen, Northern Norway

    Science.gov (United States)

    de Leon, K. C.; Schwery, D.; Yoshikawa, K.; Christiansen, H. H.; Pearce, D.

    2014-12-01

    Permafrost-affected soils are among the most fragile ecosystems in which current microbial controls on organic matter decomposition are changing as a result of climate change. Warmer conditions in the high Arctic will lead to a deepening of the seasonal active layer of permafrost, provoking changes in microbial processes and possibly resulting in exacerbated carbon degradation under increasing anoxic conditions. The viable and non-viable fractions of the microbial community in a permafrost soil from Adventdalen, Spitsbergen, Norway were subjected to a comprehensive investigation using culture-dependent and culture-independent methods. Molecular analyses using FISH (with CTC-DAPI) and amplified rDNA restriction analysis (ARDRA) on a 257cm deep core, revealed the presence of all major microbial soil groups, with the active layer having more viable cells, and a higher microbial community diversity. Carbon dioxide (CO2) and methane (CH4) flux measurements were performed to show the amount of C stored in the sample. We demonstrated that the microbial community composition from the soil in the center of the core was most likely influenced by small scale variations in environmental conditions. Community structure showed distinct shift of presence of bacterial groups along the vertical temperature gradient profile and microbial counts and diversity was found to be highest in the surface layers, decreasing with depth. It was observed that soil properties driving microbial diversity and functional potential varied across the permafrost table. Data on the variability of CO2 and CH4 distribution described in peat structure heterogeneity are important for modeling emissions on a larger scale. Furthermore, linking microbial biomass to gas distribution may elucidate the cause of peak CO2 and CH4 and their changes in relation to environmental change and peat composition.

  10. Risk assessment of climate systems for national security.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A.; Boslough, Mark Bruce Elrick; Brown, Theresa Jean; Cai, Ximing; Conrad, Stephen Hamilton; Constantine, Paul G; Dalbey, Keith R.; Debusschere, Bert J.; Fields, Richard; Hart, David Blaine; Kalinina, Elena Arkadievna; Kerstein, Alan R.; Levy, Michael; Lowry, Thomas Stephen; Malczynski, Leonard A.; Najm, Habib N.; Overfelt, James Robert; Parks, Mancel Jordan; Peplinski, William J.; Safta, Cosmin; Sargsyan, Khachik; Stubblefield, William Anthony; Taylor, Mark A.; Tidwell, Vincent Carroll; Trucano, Timothy Guy; Villa, Daniel L.

    2012-10-01

    Climate change, through drought, flooding, storms, heat waves, and melting Arctic ice, affects the production and flow of resource within and among geographical regions. The interactions among governments, populations, and sectors of the economy require integrated assessment based on risk, through uncertainty quantification (UQ). This project evaluated the capabilities with Sandia National Laboratories to perform such integrated analyses, as they relate to (inter)national security. The combining of the UQ results from climate models with hydrological and economic/infrastructure impact modeling appears to offer the best capability for national security risk assessments.

  11. Acquatorialities of the Arctic Region

    DEFF Research Database (Denmark)

    Harste, Gorm

    2013-01-01

    In order to describe the Arctic system I propose using a concept functionally equivalent to territoriality, namely aquatoriality. Whether communicating about territoriality or aquatoriality, concepts and delimitations are both contingent to forms of communication systems. I will distinguish betwe...... coding of the Arctic. These codes could then appear structurally coupled to a political system that in an organizational way appears in the Arctic Council...

  12. Remote sensing aides studies of climate and wildlife in the Arctic-on land, at sea, and in the air (Invited)

    Science.gov (United States)

    Douglas, D. C.; Durner, G. M.; Gill, R. E.; Griffith, B.; Schmutz, J. A.

    2013-12-01

    Every day a variety of remote sensing technologies collects large volumes of data that are supporting new analyses and new interpretations about how weather and climate influence the status and distribution of wildlife populations worldwide. Understanding how climate presently affects wildlife is crucial for projecting how climate change could affect wildlife in the future. This talk highlights climate-related wildlife studies by the US Geological Survey in the Arctic. The Arctic is experiencing some of the most pronounced climate changes on earth, raising concerns for species that have evolved seasonal migration strategies tuned to habitat availability and quality. On land, large herbivores such as caribou select concentrated calving areas with high abundance of rapidly growing vegetation and calf survival increases with earlier green-up and with the quantity of food available to cows at peak lactation. Geese time their migrations and reproductive efforts to coincide with optimal plant phenology and peak nutrient availability and departures from this synchrony can influence the survival of goslings. At sea, the habitats of polar bears and other sea-ice-dependent species have dramatically changed over just the past two decades. The ice pack is comprised of younger ice that melts much more extensively during summer-a trend projected to continue by all general circulation models under all but the most aggressive greenhouse gas mitigation scenarios. Studies show that by mid-century optimal polar bear habitats will be so reduced that the species may become extirpated from some regions of the Arctic. In the air, a variety of shorebird species make non-stop endurance flights between northern and southern hemispheres. The bar-tailed godwit undertakes a trans-Pacific flight between Alaska and Australasia that lasts more than seven days and spans more than 10,000 km. Studies show that godwits time their flights to coincide with favorable wind conditions, but stochastic

  13. Climate change and the loss of organic archaeological deposits in the Arctic

    DEFF Research Database (Denmark)

    Hollesen, Jørgen; Matthiesen, Henning; Møller, Anders Bjørn;

    2016-01-01

    , depositional and environmental conditions. Degradation rates of the deposits are more sensitive to increasing temperatures than natural soils and the process is accompanied by a high microbial heat production that correlates significantly with their total carbon content. We conclude that organic archaeology...... of organic archaeological deposits located in different climatic zones in West and South Greenland. The rate of degradation is investigated based on measurements of O2 consumption, CO2 production and heat production at different temperatures and water contents. Overall, there is good consistency between...... the three methods. However, at one site the, O2 consumption is markedly higher than the CO2 production, highlighting the importance of combining several measures when assessing the vulnerability of organic deposits. The archaeological deposits are highly vulnerable to degradation regardless of age...

  14. AROME-Arctic: New operational NWP model for the Arctic region

    Science.gov (United States)

    Süld, Jakob; Dale, Knut S.; Myrland, Espen; Batrak, Yurii; Homleid, Mariken; Valkonen, Teresa; Seierstad, Ivar A.; Randriamampianina, Roger

    2016-04-01

    In the frame of the EU-funded project ACCESS (Arctic Climate Change, Economy and Society), MET Norway aimed 1) to describe the present monitoring and forecasting capabilities in the Arctic; and 2) to identify the key factors limiting the forecasting capabilities and to give recommendations on key areas to improve the forecasting capabilities in the Arctic. We have observed that the NWP forecast quality is lower in the Arctic than in the regions further south. Earlier research indicated that one of the factors behind this is the composition of the observing system in the Arctic, in particular the scarceness of conventional observations. To further assess possible strategies for alleviating the situation and propose scenarios for a future Arctic observing system, we have performed a set of experiments to gain a more detailed insight in the contribution of the components of the present observing system in a regional state-of-the-art non-hydrostatic NWP model using the AROME physics (Seity et al, 2011) at 2.5 km horizontal resolution - AROME-Arctic. Our observing system experiment studies showed that conventional observations (Synop, Buoys) can play an important role in correcting the surface state of the model, but prove that the present upper-air conventional (Radiosondes, Aircraft) observations in the area are too scarce to have a significant effect on forecasts. We demonstrate that satellite sounding data play an important role in improving forecast quality. This is the case with satellite temperature sounding data (AMSU-A, IASI), as well as with the satellite moisture sounding data (AMSU-B/MHS, IASI). With these sets of observations, the AROME-Arctic clearly performs better in forecasting extreme events, like for example polar lows. For more details see presentation by Randriamampianina et al. in this session. The encouraging performance of AROME-Arctic lead us to implement it with more observations and improved settings into daily runs with the objective to

  15. Validation Test Report for the Arctic Cap Nowcast/Forecast System as a Fractures/Leads and Polynyas Product

    Science.gov (United States)

    2015-05-26

    provides nowcasts and forecasts of the global ocean environment which includes three-dimensional ocean temperature , salinity and current structure...and March 20th created instabilities in the wind-driven ice floes on the Arctic Ocean which led to multiple fractures in the ice near the camp...Test Report for the Arctic Cap Nowcast/Forecast System as a Fractures/Leads and Polynyas Product Julia W. Crout Vencore Services and Solutions, Inc

  16. Reconstruction of past methane availability in an Arctic Alaska wetland indicates climate influenced methane release during the past ~12,000 years

    Science.gov (United States)

    Wooller, Matthew J.; Pohlman, John W.; Gaglioti, Benjamin V.; Langdon, Peter; Jones, Miriam; Anthony, Katey M. Walter; Becker, Kevin W.; Hinrichs, Kai-Uwe; Elvert, Marcus

    2012-01-01

    Atmospheric contributions of methane from Arctic wetlands during the Holocene are dynamic and linked to climate oscillations. However, long-term records linking climate variability to methane availability in Arctic wetlands are lacking. We present a multi-proxy ~12,000 year paleoecological reconstruction of intermittent methane availability from a radiocarbon-dated sediment core (LQ-West) taken from a shallow tundra lake (Qalluuraq Lake) in Arctic Alaska. Specifically, stable carbon isotopic values of photosynthetic biomarkers and methane are utilized to estimate the proportional contribution of methane-derived carbon to lake-sediment-preserved benthic (chironomids) and pelagic (cladocerans) components over the last ~12,000 years. These results were compared to temperature, hydrologic, and habitat reconstructions from the same site using chironomid assemblage data, oxygen isotopes of chironomid head capsules, and radiocarbon ages of plant macrofossils. Cladoceran ephippia from ~4,000 cal year BP sediments have δ13C values that range from ~−39 to −31‰, suggesting peak methane carbon assimilation at that time. These low δ13C values coincide with an apparent decrease in effective moisture and development of a wetland that included Sphagnum subsecundum. Incorporation of methane-derived carbon by chironomids and cladocerans decreased from ~2,500 to 1,500 cal year BP, coinciding with a temperature decrease. Live-collected chironomids with a radiocarbon age of 1,640 cal year BP, and fossil chironomids from 1,500 cal year BP in the core illustrate that ‘old’ carbon has also contributed to the development of the aquatic ecosystem since ~1,500 cal year BP. The relatively low δ13C values of aquatic invertebrates (as low as −40.5‰) provide evidence of methane incorporation by lake invertebrates, and suggest intermittent climate-linked methane release from the lake throughout the Holocene.

  17. Impacts of climate change on air pollution levels in the Northern Hemisphere with special focus on Europe and the Arctic

    Directory of Open Access Journals (Sweden)

    G. B. Hedegaard

    2008-06-01

    Full Text Available The response of a selected number of chemical species is inspected with respect to climate change. The coupled Atmosphere-Ocean General Circulation Model ECHAM4-OPYC3 is providing meteorological fields for the Chemical long-range Transport Model DEHM. Three selected decades (1990s, 2040s and 2090s are inspected. The 1990s are used as a reference and validation period. In this decade an evaluation of the output from the DEHM model with ECHAM4-OPYC3 meteorology input data is carried out. The model results are tested against similar model simulations with MM5 meteorology and against observations from the EMEP monitoring sites in Europe.

    The test results from the validation period show that the overall statistics (e.g. mean values and standard deviations are similar for the two simulations. However, as one would expect the model setup with climate input data fails to predict correctly the timing of the variability in the observations. The overall performance of the ECHAM4-OPYC3 setup as meteorological input to the DEHM model is shown to be acceptable according to the applied ranking method. It is concluded that running a chemical long-range transport model on data from a "free run" climate model is scientifically sound. From the model runs of the three decades, it is found that the overall trend detected in the evolution of the chemical species, is the same between the 1990 decade and the 2040 decade and between the 2040 decade and the 2090 decade, respectively.

    The dominating impacts from climate change on a large number of the chemical species are related to the predicted temperature increase. Throughout the 21th century the ECHAM4-OPYC3 projects a global mean temperature increase of 3 K with local maxima up to 11 K in the Arctic winter based on the IPCC A2 emission scenario. As a consequence of this temperature increase, the temperature dependent biogenic emission of isoprene is predicted to increase significantly over land by

  18. Obligate larval inhibition of Ostertagia gruehneri in Rangifer tarandus? Causes and consequences in an Arctic system.

    Science.gov (United States)

    Hoar, Bryanne M; Eberhardt, Alexander G; Kutz, Susan J

    2012-09-01

    Larval inhibition is a common strategy of Trichostrongylidae nematodes that may increase survival of larvae during unfavourable periods and concentrate egg production when conditions are favourable for development and transmission. We investigated the propensity for larval inhibition in a population of Ostertagia gruehneri, the most common gastrointestinal Trichostrongylidae nematode of Rangifer tarandus. Initial experimental infections of 4 reindeer with O. gruehneri sourced from the Bathurst caribou herd in Arctic Canada suggested that the propensity for larval inhibition was 100%. In the summer of 2009 we infected 12 additional reindeer with the F1 and F2 generations of O. gruehneri sourced from the previously infected reindeer to further investigate the propensity of larval inhibition. The reindeer were divided into 2 groups and half were infected before the summer solstice (17 June) and half were infected after the solstice (16 July). Reindeer did not shed eggs until March 2010, i.e. 8 and 9 months post-infection. These results suggest obligate larval inhibition for at least 1 population of O. gruehneri, a phenomenon that has not been conclusively shown for any other trichostrongylid species. Obligate inhibition is likely to be an adaptation to both the Arctic environment and to a migratory host and may influence the ability of O. gruehneri to adapt to climate change.

  19. Origin of moisture at Arctic sites

    OpenAIRE

    Jonassen, Trine

    2016-01-01

    The hydrological cycle is an important component in the understanding of the climate system, and a good understanding of the moisture transport in the atmosphere is important in a changing climate. The climate change may have large impact on the Arctic sites. In this thesis we look at the moisture source for NEEM (North Greenland Eemian Drilling Project) in Greenland (77.45°N, 51.05°W, 2484m a.s.l.) and Tustervatn in Norway (65.83°N, 13.92°E, 439m a.s.l.), by diagnosing the origin of moisture...

  20. Understanding how lake populations of arctic char are structured and function with special consideration of the potential effects of climate change: a multi-faceted approach.

    Science.gov (United States)

    Budy, Phaedra; Luecke, Chris

    2014-09-01

    Size dimorphism in fish populations, both its causes and consequences, has been an area of considerable focus; however, uncertainty remains whether size dimorphism is dynamic or stabilizing and about the role of exogenous factors. Here, we explored patterns among empirical vital rates, population structure, abundance and trend, and predicted the effects of climate change on populations of arctic char (Salvelinus alpinus) in two lakes. Both populations cycle dramatically between dominance by small (≤300 mm) and large (>300 mm) char. Apparent survival (Φ) and specific growth rates (SGR) were relatively high (40-96%; SGR range 0.03-1.5%) and comparable to those of conspecifics at lower latitudes. Climate change scenarios mimicked observed patterns of warming and resulted in temperatures closer to optimal for char growth (15.15 °C) and a longer growing season. An increase in consumption rates (28-34%) under climate change scenarios led to much greater growth rates (23-34%). Higher growth rates predicted under climate change resulted in an even greater predicted amplitude of cycles in population structure as well as an increase in reproductive output (Ro) and decrease in generation time (Go). Collectively, these results indicate arctic char populations (not just individuals) are extremely sensitive to small changes in the number of ice-free days. We hypothesize years with a longer growing season, predicted to occur more often under climate change, produce elevated growth rates of small char and act in a manner similar to a "resource pulse," allowing a sub-set of small char to "break through," thus setting the cycle in population structure.

  1. Last straw versus Blitzkrieg overkill: Climate-driven changes in the Arctic Siberian mammoth population and the Late Pleistocene extinction problem

    Science.gov (United States)

    Nikolskiy, P. A.; Sulerzhitsky, L. D.; Pitulko, V. V.

    2011-08-01

    A set of radiocarbon dates on woolly mammoth were obtained from several regions of Arctic Siberia: the New Siberian Islands ( n = 68), north of the Yana-Indigirka Lowland ( n = 43), and the Taimyr Peninsula ( n = 18). Based on these and earlier published dates ( n = 201) from the East Arctic, a comparative analysis of the time-related density distribution of 14C dates was conducted. It was shown that the frequencies of 14C dates under certain conditions reflect temporal fluctuations in mammoth numbers. At the end of the Pleistocene the number of mammoths in the East Arctic changed in a cyclic manner in keeping with a general "Milankovitch-like" trend. The fluctuations in numbers at the end of the Pleistocene occurred synchronously with paleoenvironmental changes controlled by global climatic change. There were three minima of relative mammoth numbers during the last 50 000 years: 22 000, 14 500-19 000, and 9500 radiocarbon years ago, or around 26 000, 16-20 000, and 10 500 calendar years respectively. The last mammoths lived on the New Siberian Islands, which were connected to the continent at that time, 9470 ± 40 radiocarbon years ago (10 700 ± 70 calendar years BP). This new youngest date approximates the extinction time of mammoths in the last continental refugium of the Holarctic. The adverse combination of environmental parameters was apparently a major factor in the critical reduction in mammoth numbers. The dispersal of humans into the Arctic areas of Siberia no later than 28 000 radiocarbon years ago did not overtly influence animal numbers. Humans were not responsible for the destruction of a sustainable mammoth population. The expanding human population could have become fatal to mammoths during strong the minima of their numbers, one of which occurred at the very beginning of the Holocene.

  2. System Identification for Indoor Climate Control

    CERN Document Server

    M., A W; H., P W M; Steskens,

    2012-01-01

    The study focuses on the applicability of system identification to identify building and system dynamics for climate control design. The main problem regarding the simulation of the dynamic response of a building using building simulation software is that (1) the simulation of a large complex building is time consuming, and (2) simulation results often lack information regarding fast dynamic behaviour (in the order of seconds), since most software uses a discrete time step, usually fixed to one hour. The first objective is to study the applicability of system identification to reduce computing time for the simulation of large complex buildings. The second objective is to research the applicability of system identification to identify building dynamics based on discrete time data (one hour) for climate control design. The study illustrates that system identification is applicable for the identification of building dynamics with a frequency that is smaller as the maximum sample frequency as used for identificat...

  3. Twentieth century bipolar seesaw of the Arctic and Antarctic surface air temperatures

    Science.gov (United States)

    Chylek, Petr; Folland, Chris K.; Lesins, Glen; Dubey, Manvendra K.

    2010-04-01

    Understanding the phase relationship between climate changes in the Arctic and Antarctic regions is essential for our understanding of the dynamics of the Earth's climate system. In this paper we show that the 20th century de-trended Arctic and Antarctic temperatures vary in anti-phase seesaw pattern - when the Arctic warms the Antarctica cools and visa versa. This is the first time that a bi-polar seesaw pattern has been identified in the 20th century Arctic and Antarctic temperature records. The Arctic (Antarctic) de-trended temperatures are highly correlated (anti-correlated) with the Atlantic Multi-decadal Oscillation (AMO) index suggesting the Atlantic Ocean as a possible link between the climate variability of the Arctic and Antarctic regions. Recent accelerated warming of the Arctic results from a positive reinforcement of the linear warming trend (due to an increasing concentration of greenhouse gases and other possible forcings) by the warming phase of the multidecadal climate variability (due to fluctuations of the Atlantic Ocean circulation).

  4. QRA techniques on dynamic positioning systems during drilling operations in the Arctic: With emphasis on the dynamic positioning operator

    OpenAIRE

    2015-01-01

    With the Norwegian government moving the ice edge farther north than ever before, opening for new areas for petroleum exploration, it will need research on how these areas can affect oil and gas operations. A sensitive environment along with the harsh Arctic climate and remote distances means that severe accidents, like blowouts, will have serious impacts and make cleanup and rescue actions to challenging operations. Additionally, humans working under these conditions are prone to be affected...

  5. TOPAZ4: an ocean-sea ice data assimilation system for the North Atlantic and Arctic

    Directory of Open Access Journals (Sweden)

    P. Sakov

    2012-04-01

    Full Text Available We present a detailed description of TOPAZ4, the latest version of TOPAZ – a coupled ocean-sea ice data assimilation system for the North Atlantic Ocean and Arctic. It is the only operational, large-scale ocean data assimilation system that uses the ensemble Kalman filter. This means that TOPAZ features a time-evolving, state-dependent estimate of the state error covariance. Based on results from the pilot MyOcean reanalysis for 2003–2008, we demonstrate that TOPAZ4 produces a realistic estimate of the ocean circulation and the sea ice. We find that the ensemble spread for temperature and sea-level remains fairly constant throughout the reanalysis demonstrating that the data assimilation system is robust to ensemble collapse. Moreover, the ensemble spread for ice concentration is well correlated with the actual errors. This indicates that the ensemble statistics provide reliable state-dependent error estimates – a feature that is unique to ensemble-based data assimilation systems. We demonstrate that the quality of the reanalysis changes when different sea surface temperature products are assimilated, or when in situ profiles below the ice in the Arctic Ocean are assimilated. We find that data assimilation improves the match to independent observations compared to a free model. Improvements are particularly noticeable for ice thickness, salinity in the Arctic, and temperature in the Fram Strait, but not for transport estimates or underwater temperature. At the same time, the pilot reanalysis has revealed several flaws in the system that have degraded its performance. Finally, we show that a simple bias estimation scheme can effectively detect the seasonal or constant bias in temperature and sea-level.

  6. An analysis of the carbon balance of the Arctic Basin

    Energy Technology Data Exchange (ETDEWEB)

    Mcguire, David [University of Alaska; Hayes, Daniel J [ORNL; Kicklighter, David W. [Ecosystem Center, The; Manizza, Manfredi [Massachusetts Institute of Technology (MIT); Zhuang, Qianlai [Purdue University; Chen, Min [Purdue University; Follows, Michael J [Massachusetts Institute of Technology (MIT); Gurney, Kevin [Purdue University; Mcclelland, James W [University of Texas; Melillo, Jerry [Marine Biological Laboratory; Peterson, Bruce [Marine Biological Laboratory; Prinn, Ronald [Massachusetts Institute of Technology (MIT)

    2010-01-01

    This study used several model-based tools to analyse the dynamics of the Arctic Basin between 1997 and 2006 as a linked system of land-ocean-atmosphere C exchange. The analysis estimates that terrestrial areas of the Arctic Basin lost 62.9 Tg C yr 1 and that the Arctic Ocean gained 94.1 Tg C yr 1. Arctic lands and oceans were a net CO2 sink of 108.9 Tg C yr 1, which is within the range of uncertainty in estimates from atmospheric inversions. Although both lands and oceans of the Arctic were estimated to be CO2 sinks, the land sink diminished in strength because of increased fire disturbance compared to previous decades, while the ocean sink increased in strength because of increased biological pump activity associated with reduced sea ice cover. Terrestrial areas of the Arctic were a net source of 41.5 Tg CH4 yr 1 that increased by 0.6 Tg CH4 yr 1 during the decade of analysis, a magnitude that is comparable with an atmospheric inversion of CH4. Because the radiative forcing of the estimated CH4 emissions is much greater than the CO2 sink, the analysis suggests that the Arctic Basin is a substantial net source of green house gas forcing to the climate system.

  7. Reconciliation of essential process parameters for an enhanced predictability of Arctic stratospheric ozone loss and its climate interactions (RECONCILE: activities and results

    Directory of Open Access Journals (Sweden)

    M. von Hobe

    2013-09-01

    Full Text Available The international research project RECONCILE has addressed central questions regarding polar ozone depletion, with the objective to quantify some of the most relevant yet still uncertain physical and chemical processes and thereby improve prognostic modelling capabilities to realistically predict the response of the ozone layer to climate change. This overview paper outlines the scope and the general approach of RECONCILE, and it provides a summary of observations and modelling in 2010 and 2011 that have generated an in many respects unprecedented dataset to study processes in the Arctic winter stratosphere. Principally, it summarises important outcomes of RECONCILE including (i better constraints and enhanced consistency on the set of parameters governing catalytic ozone destruction cycles, (ii a better understanding of the role of cold binary aerosols in heterogeneous chlorine activation, (iii an improved scheme of polar stratospheric cloud (PSC processes that includes heterogeneous nucleation of nitric acid trihydrate (NAT and ice on non-volatile background aerosol leading to better model parameterisations with respect to denitrification, and (iv long transient simulations with a chemistry-climate model (CCM updated based on the results of RECONCILE that better reproduce past ozone trends in Antarctica and are deemed to produce more reliable predictions of future ozone trends. The process studies and the global simulations conducted in RECONCILE show that in the Arctic, ozone depletion uncertainties in the chemical and microphysical processes are now clearly smaller than the sensitivity to dynamic variability.

  8. Reconciliation of essential process parameters for an enhanced predictability of Arctic stratospheric ozone loss and its climate interactions (RECONCILE): activities and results

    Science.gov (United States)

    von Hobe, M.; Bekki, S.; Borrmann, S.; Cairo, F.; D'Amato, F.; Di Donfrancesco, G.; Dörnbrack, A.; Ebersoldt, A.; Ebert, M.; Emde, C.; Engel, I.; Ern, M.; Frey, W.; Genco, S.; Griessbach, S.; Grooß, J.-U.; Gulde, T.; Günther, G.; Hösen, E.; Hoffmann, L.; Homonnai, V.; Hoyle, C. R.; Isaksen, I. S. A.; Jackson, D. R.; Jánosi, I. M.; Jones, R. L.; Kandler, K.; Kalicinsky, C.; Keil, A.; Khaykin, S. M.; Khosrawi, F.; Kivi, R.; Kuttippurath, J.; Laube, J. C.; Lefèvre, F.; Lehmann, R.; Ludmann, S.; Luo, B. P.; Marchand, M.; Meyer, J.; Mitev, V.; Molleker, S.; Müller, R.; Oelhaf, H.; Olschewski, F.; Orsolini, Y.; Peter, T.; Pfeilsticker, K.; Piesch, C.; Pitts, M. C.; Poole, L. R.; Pope, F. D.; Ravegnani, F.; Rex, M.; Riese, M.; Röckmann, T.; Rognerud, B.; Roiger, A.; Rolf, C.; Santee, M. L.; Scheibe, M.; Schiller, C.; Schlager, H.; Siciliani de Cumis, M.; Sitnikov, N.; Søvde, O. A.; Spang, R.; Spelten, N.; Stordal, F.; Sumińska-Ebersoldt, O.; Ulanovski, A.; Ungermann, J.; Viciani, S.; Volk, C. M.; vom Scheidt, M.; von der Gathen, P.; Walker, K.; Wegner, T.; Weigel, R.; Weinbruch, S.; Wetzel, G.; Wienhold, F. G.; Wohltmann, I.; Woiwode, W.; Young, I. A. K.; Yushkov, V.; Zobrist, B.; Stroh, F.

    2013-09-01

    The international research project RECONCILE has addressed central questions regarding polar ozone depletion, with the objective to quantify some of the most relevant yet still uncertain physical and chemical processes and thereby improve prognostic modelling capabilities to realistically predict the response of the ozone layer to climate change. This overview paper outlines the scope and the general approach of RECONCILE, and it provides a summary of observations and modelling in 2010 and 2011 that have generated an in many respects unprecedented dataset to study processes in the Arctic winter stratosphere. Principally, it summarises important outcomes of RECONCILE including (i) better constraints and enhanced consistency on the set of parameters governing catalytic ozone destruction cycles, (ii) a better understanding of the role of cold binary aerosols in heterogeneous chlorine activation, (iii) an improved scheme of polar stratospheric cloud (PSC) processes that includes heterogeneous nucleation of nitric acid trihydrate (NAT) and ice on non-volatile background aerosol leading to better model parameterisations with respect to denitrification, and (iv) long transient simulations with a chemistry-climate model (CCM) updated based on the results of RECONCILE that better reproduce past ozone trends in Antarctica and are deemed to produce more reliable predictions of future ozone trends. The process studies and the global simulations conducted in RECONCILE show that in the Arctic, ozone depletion uncertainties in the chemical and microphysical processes are now clearly smaller than the sensitivity to dynamic variability.

  9. Inter-model diversity of Arctic amplification caused by global warming and its relationship with the Inter-tropical Convergence Zone in CMIP5 climate models

    Science.gov (United States)

    Yim, Bo Young; Yeh, Sang-Wook; Kug, Jong-Seong

    2016-08-01

    Surface-based Arctic amplification (AA) has experienced a remarkable increase in recent decades. Therefore, it is important to understand how Arctic warming might change in response to global warming. By analyzing the Coupled Model Intercomparison Project Phase 5 (CMIP5) multi-model dataset, we examine how AA correlates with changes in tropical Pacific precipitation in response to global warming. It is found that that the changes in the latitudinal position of the Inter-tropical Convergence Zone (ITCZ) are associated to the simulated AA strength in the CMIP5 climate models. Specifically, AA tends to be stronger (weaker) in models where the ITCZ shifts relatively more northward (southward). Further analysis indicates that the inter-model diversity of AA strength in the CMIP5 climate models is related to the changes in large-scale atmospheric circulation associated with the meridional shift of the ITCZ. These results emphasize a close relationship between AA and changes in tropical Pacific precipitation in response to global warming.

  10. Polar stratospheric ozone: interactions with climate change, results from the EU project RECONCILE, and the 2010/11 Arctic ozone hole

    Science.gov (United States)

    von Hobe, Marc

    2013-04-01

    One of the most profound and well known examples of human impacts on atmospheric chemistry is the so called ozone hole. During the second half of the 20th century, anthropogenic emissions of chlorofluorocarbons (CFCs) led to a significant increase in stratospheric chlorine levels and hence the rate of ozone removal by catalytic cycles involving chlorine. While CFCs were essentially banned by the 1987 Montreal Protocol and its subsequent amendments, and stratospheric chlorine levels have recently started to decline again, another anthropogenic influence may at least delay the recovery of the stratospheric ozone layer: climate change, with little doubt a result of human emissions of carbon dioxide and other greenhouse gases, has led to changes in stratospheric temperature and circulation. The large ozone losses that typically occur in polar regions in spring are particularly affected by these changes. Here, we give an overview of the ozone-climate interactions affecting polar stratospheric ozone loss, and present latest results from the international research project RECONCILE funded by the European Commission. Remaining open questions will be discussed including the possible impacts of recently suggested geoengineering concepts to artificially enhance the stratospheric aerosol loading. A special focus will also be put on the 2010/11 Arctic winter that saw the first Arctic Ozone hole, including an impact study on surface UV radiation in the densely populated northern mid-latitudes.

  11. Modeling the seasonal variability of a coupled Arctic ice-ocean system

    Science.gov (United States)

    Hakkinen, Sirpa; Mellor, George L.

    1992-01-01

    The seasonal variability of the ice-ocean system in the Arctic Basin and the Norwegian, Greenland, and Barents Seas was modeled using a three-dimensional coupled ice-ocean model developed at Princeton University. The snow-ice model uses a three-level thermodynamic scheme similar to Semtner's (1976), but is extended to include the effect of leads. It is shown that simulations using the climatological monthly forcing fields produce a realistic seasonal variability of the ice cover. The ice thickness had a considerable sensitivity to the choice of the long-wave back radiation scheme, but these effects can be reduced through dynamical factors.

  12. Multi-model assessment of linkages between eastern Arctic sea-ice variability and the Euro-Atlantic atmospheric circulation in current climate

    Science.gov (United States)

    García-Serrano, J.; Frankignoul, C.; King, M. P.; Arribas, A.; Gao, Y.; Guemas, V.; Matei, D.; Msadek, R.; Park, W.; Sanchez-Gomez, E.

    2016-11-01

    A set of ensemble integrations from the Coupled Model Intercomparison Project phase 5, with historical forcing plus RCP4.5 scenario, are used to explore if state-of-the-art climate models are able to simulate previously reported linkages between sea-ice concentration (SIC) anomalies over the eastern Arctic, namely in the Greenland-Barents-Kara Seas, and lagged atmospheric circulation that projects on the North Atlantic Oscillation (NAO)/Arctic Oscillation (AO). The study is focused on variability around the long-term trends, so that all anomalies are detrended prior to analysis; the period of study is 1979-2013. The model linkages are detected by applying maximum covariance analysis. As also found in observational data, all the models considered here show a statistically significant link with sea-ice reduction over the eastern Arctic followed by a negative NAO/AO-like pattern. If the simulated relationship is found at a lag of one month, the results suggest that a stratospheric pathway could be at play as the driving mechanism; in observations this is preferentially shown for SIC in November. The interference of a wave-like anomaly over Eurasia, accompanying SIC changes, with the climatological wave pattern appears to be key in setting the mediating role of the stratosphere. On the other hand, if the simulated relationship is found at a lag of two months, the results suggest that tropospheric dynamics are dominant, presumably due to transient eddy feedback; in observations this is preferentially shown for SIC in December. The results shown here and previous evidence from atmosphere-only experiments emphasize that there could be a detectable influence of eastern Arctic SIC variability on mid-latitude atmospheric circulation anomalies. Even if the mechanisms are robust among the models, the timing of the simulated linkages strongly depends on the model and does not generally mimic the observational ones. This implies that the atmospheric sensitivity to sea

  13. Development of arctic wind technology

    Energy Technology Data Exchange (ETDEWEB)

    Holttinen, H.; Marjaniemi, M.; Antikainen, P. [VTT Energy, Espoo (Finland)

    1998-10-01

    The climatic conditions of Lapland set special technical requirements for wind power production. The most difficult problem regarding wind power production in arctic regions is the build-up of hard and rime ice on structures of the machine

  14. Does a relationship between Arctic low clouds and sea ice matter?

    Science.gov (United States)

    Taylor, Patrick C.

    2017-02-01

    Arctic low clouds strongly affect the Arctic surface energy budget. Through this impact Arctic low clouds influence important aspects of the Arctic climate system, namely surface and atmospheric temperature, sea ice extent and thickness, and atmospheric circulation. Arctic clouds are in turn influenced by these elements of the Arctic climate system, and these interactions create the potential for Arctic cloud-climate feedbacks. To further our understanding of potential Arctic cloud-climate feedbacks, the goal of this paper is to quantify the influence of atmospheric state on the surface cloud radiative effect (CRE) and its covariation with sea ice concentration (SIC). We build on previous research using instantaneous, active remote sensing satellite footprint data from the NASA A-Train. First, the results indicate significant differences in the surface CRE when stratified by atmospheric state. Second, there is a weak covariation between CRE and SIC for most atmospheric conditions. Third, the results show statistically significant differences in the average surface CRE under different SIC values in fall indicating a 3-5 W m-2 larger LW CRE in 0% versus 100% SIC footprints. Because systematic changes on the order of 1 W m-2 are sufficient to explain the observed long-term reductions in sea ice extent, our results indicate a potentially significant amplifying sea ice-cloud feedback, under certain meteorological conditions, that could delay the fall freeze-up and influence the variability in sea ice extent and volume. Lastly, a small change in the frequency of occurrence of atmosphere states may yield a larger Arctic cloud feedback than any cloud response to sea ice.

  15. Unmanned Aerial Systems during the Coordinated Investigation of Climate-Cryosphere Interaction at Svalbard, Norway

    Science.gov (United States)

    Burkhart, J. F.; Bates, T. S.; Quinn, P.; Storvold, R.; Herber, A.; Vitale, V.; Lesenkov, S.; Cicci/Vauuav Science Team

    2011-12-01

    During Spring 2011 an intensive investigation of climate-cryosphere interaction was conducted in Svalbard, Norway. A primary objective of the campaign was to investigate processes related to the deposition of aerosols to the Arctic cryosphere. Moreover, the campaign provided a first-time opportunity to test several novel data acquisition platforms. Of interest to this session are the three Unmanned Aerial System (UAS) platforms that flew cooperatively with oversight from the Norwegian Civil Aviation Authority (CAA). The campaign presented the unique opportunity for a CAA to regulate UAS platforms; both private and foreign government-owned aircraft (Norway, USA, and Russia). Further, it highlighted challenges, both political and logistical, related to conducting such an operation. We present an overview of the 'Coordinated Investigation of Climate-Cryosphere Interaction' campaign, and highlight the novel and valuable contributions from each of the UAS platforms. Our presentation includes an overview of the different platform capabilities, a discussion of the scientific merits of the platforms, insight into the political process for UAS operations in the Arctic, and a summary of the acquired contributions toward the goals of the CICCI project.

  16. Quaternary Arctic Climate Change of the past 2.8 Ma as reconstructed from sediments of Lake El'gygytgyn, NE Russia (Invited)

    Science.gov (United States)

    Wennrich, V.; Melles, M.; Brigham-Grette, J.; Minyuk, P.; Nowaczyk, N. R.; Deconto, R. M.; Anderson, P. A.; Andreev, A. A.; Haltia, E.; Kukkonen, M.; Lozhkin, A. V.; Rosen, P.; Tarasov, P. E.

    2013-12-01

    Scientific deep drilling at Lake El'gygtygyn in Chukotka, northeastern Russia (67.5° N, 172° E) revealed the first high-resolution record of environmental history in the Arctic that spans the past 3.6 Ma continuously (Melles et al. 2012, Brigham-Grette et al. 2013). In this presentation we focus on the end-member glacial and interglacial climatic conditions of the past 2.8 Ma as clearly reflected in the pelagic lake sediments recovered. Peak glacial conditions, when mean annual air temperatures at least 3.3 (×0.9) °C lower than today led to perennial lake ice (Nolan 2013), first appeared at Lake El'gygytgyn 2.602 - 2.598 Ma ago, during marine isotope stage (MIS) 104. These pervasive glacial episodes gradually increase in frequency from ~2.3 to ~1.8 Ma, eventually concurring with all glacials and several stadials reflected globally in stacked marine isotope records. Particularly warm interglacials, in contrast, experienced a long ice-free season and enhanced nutrient supply from the catchment, which allowed for significantly higher primary production than today. These settings were most pronounced for MIS 11c, 31, 49, 55, 77, 87, 91, and 93. Their exceptional character becomes evident based upon pollen-based climate reconstructions in selected interglacials, showing that the mean temperature of the warmest month and the annual precipitation during the thermal maxima of MIS 11c and 31 ('super' interglacials) were 4-5 °C and ~300 mm higher than those of MIS 1 and 5e ('normal' interglacials), respectively. According to climate simulations, the exceptional warm and moist climates at least during MIS 11c cannot be explained by the natural variability in Earth's orbital parameters and greenhouse gas concentrations alone. A remarkable coincidence of the super interglacials at Lake El'gygytgyn with diatomite layers in the Antarctic ANDRILL 1B, which reflect periods of a diminished West Antarctic Ice Sheet (WAIS) (Naish et al. 2009, Pollard and DeConto 2009), suggests

  17. Reconstruction of the Arctic Ocean environment during the Eocene Azolla interval using geochemical proxies and climate modeling. Geologica Ultraiectina (331)

    NARCIS (Netherlands)

    Speelman, E.N.

    2010-01-01

    With the realization that the Arctic Ocean was covered with enormous quantities of the aquatic floating fern Azolla 49 Myrs ago, new questions regarding the Eocene conditions facilitating these blooms arose. This dissertation describes the reconstruction of paleo-environmental conditions facilitatin

  18. Network of Networks and the Climate System

    Science.gov (United States)

    Kurths, Jürgen; Boers, Niklas; Bookhagen, Bodo; Donges, Jonathan; Donner, Reik; Malik, Nishant; Marwan, Norbert; Stolbova, Veronika

    2013-04-01

    Network of networks is a new direction in complex systems science. One can find such networks in various fields, such as infrastructure (power grids etc.), human brain or Earth system. Basic properties and new characteristics, such as cross-degree, or cross-betweenness will be discussed. This allows us to quantify the structural role of single vertices or whole sub-networks with respect to the interaction of a pair of subnetworks on local, mesoscopic, and global topological scales. Next, we consider an inverse problem: Is there a backbone-like structure underlying the climate system? For this we propose a method to reconstruct and analyze a complex network from data generated by a spatio-temporal dynamical system. This technique is then applied to 3-dimensional data of the climate system. We interpret different heights in the atmosphere as different networks and the whole as a network of networks. This approach enables us to uncover relations to global circulation patterns in oceans and atmosphere. The global scale view on climate networks offers promising new perspectives for detecting dynamical structures based on nonlinear physical processes in the climate system. This concept is applied to Indian Monsoon data in order to characterize the regional occurrence of strong rain events and its impact on predictability. References: Arenas, A., A. Diaz-Guilera, J. Kurths, Y. Moreno, and C. Zhou, Phys. Reports 2008, 469, 93. Donges, J., Y. Zou, N. Marwan, and J. Kurths, Europhys. Lett. 2009, 87, 48007. Donner, R., Y. Zou, J. Donges, N. Marwan, and J. Kurths, Phys. Rev. E 2010, 81, 015101(R ). Mokhov, I. I., D. A. Smirnov, P. I. Nakonechny, S. S. Kozlenko, E. P. Seleznev, and J. Kurths, Geophys. Res. Lett. 2011, 38, L00F04. Malik, N., B. Bookhagen, N. Marwan, and J. Kurths, Climate Dynamics, 2012, 39, 971. Donges, J., H. Schultz, N. Marwan, Y. Zou, J. Kurths, Eur. J. Phys. B 2011, 84, 635-651. Donges, J., R. Donner, M. Trauth, N. Marwan, H.J. Schellnhuber, and J. Kurths

  19. Arctic security and Norway

    Energy Technology Data Exchange (ETDEWEB)

    Tamnes, Rolf

    2013-03-01

    Global warming is one of the most serious threats facing mankind. Many regions and countries will be affected, and there will be many losers. The earliest and most intense climatic changes are being experienced in the Arctic region. Arctic average temperature has risen at twice the rate of the global average in the past half century. These changes provide an early indication for the world of the environmental and societal significance of global warming. For that reason, the Arctic presents itself as an important scientific laboratory for improving our understanding of the causes and patterns of climate changes. The rapidly rising temperature threatens the Arctic ecosystem, but the human consequences seem to be far less dramatic there than in many other places in the world. According to the U.S. National Intelligence Council, Russia has the potential to gain the most from increasingly temperate weather, because its petroleum reserves become more accessible and because the opening of an Arctic waterway could provide economic and commercial advantages. Norway might also be fortunate. Some years ago, the Financial Times asked: #Left Double Quotation Mark#What should Norway do about the fact that global warming will make their climate more hospitable and enhance their financial situation, even as it inflicts damage on other parts of the world?#Right Double Quotation Mark#(Author)

  20. [Reactivity of the physiological system of the connective tissue and immunoglobulin levels in divers of the Arctic Pri-Elbrus regions].

    Science.gov (United States)

    Pavlovich, S I

    1991-01-01

    The functional state of the conjunctive tissue system in deep-divers has been evaluated by the Kavetsky-Leshchinsky method. The content of different classes of immunoglobulins in the mucosa of upper respiratory tracts has been studied by the fluorescent antibody method under conditions of the Arctic and highland. The long-term divings cause a decrease in the reactivity of a physiological system of conjunctive tissue and a shift in the parameters of the immunological organism status. These changes are found to be more pronounced in the deep divers with underwater work experience of more than 2,000 hours. The general immunological reactivity of the organism rises significantly after 2.5 months stay under conditions of the Elbrus (height--2100 m). These facts confirm an idea that favourable climatic factors of the highland are expedient to be used in the complex of rehabilitation measures for deep-divers.

  1. Abnormal Winter Melting of the Arctic Sea Ice Cap Observed by the Spaceborne Passive Microwave Sensors

    Science.gov (United States)

    Lee, Seongsuk; Yi, Yu

    2016-12-01

    The spatial size and variation of Arctic sea ice play an important role in Earth’s climate system. These are affected by conditions in the polar atmosphere and Arctic sea temperatures. The Arctic sea ice concentration is calculated from brightness temperature data derived from the Defense Meteorological Satellite program (DMSP) F13 Special Sensor Microwave/Imagers (SSMI) and the DMSP F17 Special Sensor Microwave Imager/Sounder (SSMIS) sensors. Many previous studies point to significant reductions in sea ice and their causes. We investigated the variability of Arctic sea ice using the daily sea ice concentration data from passive microwave observations to identify the sea ice melting regions near the Arctic polar ice cap. We discovered the abnormal melting of the Arctic sea ice near the North Pole during the summer and the winter. This phenomenon is hard to explain only surface air temperature or solar heating as suggested by recent studies. We propose a hypothesis explaining this phenomenon. The heat from the deep sea in Arctic Ocean ridges and/ or the hydrothermal vents might be contributing to the melting of Arctic sea ice. This hypothesis could be verified by the observation of warm water column structure below the melting or thinning arctic sea ice through the project such as Coriolis dataset for reanalysis (CORA).

  2. Shifts in the hydrodynamic regime determine patterns of regional changes of the Arctic Ocean carbon cycle in future climate change projections

    Science.gov (United States)

    Ilyina, T.; Heinze, M.; Li, H.; Jungclaus, J. H.; Six, K. D.

    2015-12-01

    In future projections the Arctic Ocean carbon cycle is a hotspot for changes driven by rising CO2 emissions. Concomitantly, the Arctic Ocean hydrodynamic regime undergoes substantial shifts so the net effect on the carbon cycle is not intuitively clear. In the high CO2 scenario RCP8.5 extended until 2300 in projections of the Max Planck Institute's Earth System Model, the averaged Arctic Ocean surface temperature rises by 4°C in 2100 and by 10°C in 2300, respectively. The Arctic becomes free of summer sea ice in the second half of the 21st century, whereas winter sea ice disappears at the beginning of the 23rd century. Owing to increased sea ice melting and runoff, fresh water content increases gradually until the end of the 22nd century and then drops abruptly as a result of an intensification of the saline Atlantic water inflow. Accumulation of Atlantic water collapses the halocline in the central basin of the Arctic Ocean by the first half of the 23rd century. Ongoing warming enhances thermal stratification and the mixed layer shoales. In contrast, halocline erosion and the cooling of the ice free water act in concert to favor formation of convection cells in the central basin. Freshening in the Canada basin and transport of salty water into the Eurasian basin generate a dipole structure in the anomalies of surface salinity. Driven by the rising CO2, the averaged dissolved inorganic carbon (DIC) is growing. Changes in the averaged total alkalinity (TA) go along with the fresh water content evolution and decreasing carbonate ion concentration so that TA drops below preindustrial values. Yet, along with salinity, the Eurasian basin receives waters with higher DIC and TA from the Atlantic. As a result, the distributions of TA and DIC anomalies resemble the dipole pattern projected for salinity. We show that while future changes in the Arctic Ocean carbon cycle proceed at rates determined by atmospheric CO2 levels, the regional patterns are driven by shifts in the

  3. Variable temperature seat climate control system

    Science.gov (United States)

    Karunasiri, Tissa R.; Gallup, David F.; Noles, David R.; Gregory, Christian T.

    1997-05-06

    A temperature climate control system comprises a variable temperature seat, at least one heat pump, at least one heat pump temperature sensor, and a controller. Each heat pump comprises a number of Peltier thermoelectric modules for temperature conditioning the air in a main heat exchanger and a main exchanger fan for passing the conditioned air from the main exchanger to the variable temperature seat. The Peltier modules and each main fan may be manually adjusted via a control switch or a control signal. Additionally, the temperature climate control system may comprise a number of additional temperature sensors to monitor the temperature of the ambient air surrounding the occupant as well as the temperature of the conditioned air directed to the occupant. The controller is configured to automatically regulate the operation of the Peltier modules and/or each main fan according to a temperature climate control logic designed both to maximize occupant comfort during normal operation, and minimize possible equipment damage, occupant discomfort, or occupant injury in the event of a heat pump malfunction.

  4. Some discussions on Arctic vortex

    Institute of Scientific and Technical Information of China (English)

    Li Hai; Sun Lantao; Wu Huiding; Li Xiang

    2006-01-01

    The Arctic vortex is a persistent large-scale cyclonic circulation in the middle and upper troposphere and the stratosphere. Its activity and variation control the semi-permanent active centers of Pan-Arctic and the short-time cyclone activity in the subarctic areas. Its strength variation, which directly relates to the atmosphere, ocean, sea ice and ecosystem of the Arctic, can affect the lower atmospheric circulation, the weather of subarctic area and even the weather of middle latitude areas. The 2003 Chinese Second Arctic Research Expedition experienced the transition of the stratosphereic circulation from a warm anticyclone to a cold cyclone during the ending period of Arctic summertime, a typical establishing process of the polar vortex circulation. The impact of the polar vortex variation on the low-level circulation has been investigated by some scientists through studying the coupling mechanisms of the stratosphere and troposphere. The impact of the Stratospheric Sudden Warming (SFW) events on the polar vortex variation was drawing people's great attention in the fifties of the last century. The Arctic Oscillation (AO) , relating to the variation of the Arctic vortex, has been used to study the impact of the Arctic vortex on climate change. The recent Arctic vortex studies are simply reviewed and some discussions on the Arctic vertex are given in the paper. Some different views and questions are also discussed.

  5. Arctic whaling : proceedings of the International Symposium Arctic Whaling February 1983

    NARCIS (Netherlands)

    Jacob, H.K. s'; Snoeijing, K

    1984-01-01

    Contents: D.M. Hopkins and Louie Marincovich Jr. Whale Biogeography and the history of the Arctic Basin P.M. Kellt, J.H.W. Karas and L.D. Williams Arctic Climate: Past, Present and Future Torgny E. Vinje On the present state and the future fate of the Arctic sea ice cover P.J.H. van Bree On the biol

  6. Arctic Browning: vegetation damage and implications for carbon balance.

    Science.gov (United States)

    Treharne, Rachael; Bjerke, Jarle; Emberson, Lisa; Tømmervik, Hans; Phoenix, Gareth

    2016-04-01

    'Arctic browning' is the loss of biomass and canopy in Arctic ecosystems. This process is often driven by climatic and biological extreme events - notably extreme winter warm periods, winter frost-drought and severe outbreaks of defoliating insects. Evidence suggests that browning is becoming increasingly frequent and severe at the pan-arctic scale, a view supported by observations from more intensely observed regions, with major and unprecedented vegetation damage reported at landscape (>1000km2) and regional (Nordic Arctic Region) scales in recent years. Critically, the damage caused by these extreme events is in direct opposition to 'Arctic greening', the well-established increase in productivity and shrub abundance observed at high latitudes in response to long-term warming. This opposition creates uncertainty as to future anticipated vegetation change in the Arctic, with implications for Arctic carbon balance. As high latitude ecosystems store around twice as much carbon as the atmosphere, and vegetation impacts are key to determining rates of loss or gain of ecosystem carbon stocks, Arctic browning has the potential to influence the role of these ecosystems in global climate. There is therefore a clear need for a quantitative understanding of the impacts of browning events on key ecosystem carbon fluxes. To address this, field sites were chosen in central and northern Norway and in Svalbard, in areas known to have been affected by either climatic extremes or insect outbreak and subsequent browning in the past four years. Sites were chosen along a latitudinal gradient to capture both conditions already causing vegetation browning throughout the Norwegian Arctic, and conditions currently common at lower latitudes which are likely to become more damaging further North as climate change progresses. At each site the response of Net Ecosystem CO2 Exchange to light was measured using a LiCor LI6400 Portable Photosynthesis system and a custom vegetation chamber with

  7. Short Communication: Atmospheric moisture transport, the bridge between ocean evaporation and Arctic ice melting

    Directory of Open Access Journals (Sweden)

    L. Gimeno

    2015-06-01

    Full Text Available If we could choose a region where the effects of global warming are likely to be pronounced and considerable, and at the same time one where the changes could affect the global climate in similarly asymmetric way with respect to other regions, this would unequivocally be the Arctic. The atmospheric branch of the hydrological cycle lies behind the linkages between the Arctic system and the global climate. Changes in the atmospheric moisture transport have been proposed as a vehicle for interpreting the most significant changes in the Arctic region. This is because the transport of moisture from the extratropical regions to the Arctic has increased in recent decades, and is expected to increase within a warming climate. This increase could be due either to changes in circulation patterns which have altered the moisture sources, or to changes in the intensity of the moisture sources because of enhanced evaporation, or a combination of these two mechanisms. In this short communication we focus on the assessing more objectively the strong link between ocean evaporation trends and Arctic Sea ice melting. We will critically analyze several recent results suggesting links between moisture transport and the extent of sea-ice in the Arctic, this being one of the most distinct indicators of continuous climate change both in the Arctic and on a global scale. To do this we will use a sophisticated Lagrangian approach to develop a more robust framework on some of these previous disconnect ng results, using new information and insights. Among the many mechanisms that could be involved are hydrological (increased Arctic river discharges, radiative (increase of cloud cover and water vapour and meteorological (increase in summer storms crossing the Arctic, or increments in precipitation.

  8. Organizational Climate Assessment: a Systemic Perspective

    Science.gov (United States)

    Argentero, Piergiorgio; Setti, Ilaria

    A number of studies showed how the set up of an involving and motivating work environment represents a source for organizational competitive advantage: in this view organizational climate (OC) research occupies a preferred position in current I/O psychology. The present study is a review carried out to establish the breadth of the literature on the characteristics of OC assessment considered in a systemic perspective. An organization with a strong climate is a work environment whose members have similar understanding of the norms and practices and share the same expectations. OC should be considered as a sort of emergent entity and, as such, it can be studied only within a systemic perspective because it is linked with some organizational variables, in terms of antecedents (such as the organization's internal structure and its environmental features) and consequences (such as job performance, psychological well-being and withdrawal) of the climate itself. In particular, when employees have a positive view of their organizational environment, consistently with their values and interests, they are more likely to identify their personal goals with those of the organization and, in turn, to invest a greater effort to pursue them: the employees' perception of the organizational environment is positively related to the key outcomes such as job involvement, effort and performance. OC analysis could also be considered as an effective Organizational Development (OD) tool: in particular, the Survey Feedback, that is the return of the OC survey results, could be an effective instrument to assess the efficacy of specific OD programs, such as Team Building, TQM and Gainsharing. The present study is focused on the interest to investigate all possible variables which are potential moderators of the climate - outcome relationship: therefore future researches in the OC field should consider a great variety of organizational variables, considered in terms of antecedents and effects

  9. Abrupt Climate Change and the Atlantic Meridional Overturning Circulation: sensitivity and non-linear response to Arctic/sub-Arctic freshwater pulses. Collaborative research. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Christopher [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States)

    2015-06-15

    This project investigated possible mechanisms by which melt-water pulses can induce abrupt change in the Atlantic Meridional Overturning Circulation (AMOC) magnitude. AMOC magnitude is an important ingredient in present day climate. Previous studies have hypothesized abrupt reduction in AMOC magnitude in response to influxes of glacial melt water into the North Atlantic. Notable fresh-water influxes are associated with the terminus of the last ice age. During this period large volumes of melt water accumulated behind retreating ice sheets and subsequently drained rapidly when the ice weakened sufficiently. Rapid draining of glacial lakes into the North Atlantic is a possible origin of a number of paleo-record abrupt climate shifts. These include the Younger-Dryas cooling event and the 8,200 year cooling event. The studies undertaken focused on whether the mechanistic sequence by which glacial melt-water impacts AMOC, which then impacts Northern Hemisphere global mean surface temperature, is dynamically plausible. The work has implications for better understanding past climate stability. The work also has relevance for today’s environment, in which high-latitude ice melting in Greenland appears to be driving fresh water outflows at an accelerating pace.

  10. Skillful seasonal forecasts of Arctic sea ice retreat and advance dates in a dynamical forecast system

    Science.gov (United States)

    Sigmond, M.; Reader, M. C.; Flato, G. M.; Merryfield, W. J.; Tivy, A.

    2016-12-01

    The need for skillful seasonal forecasts of Arctic sea ice is rapidly increasing. Technology to perform such forecasts with coupled atmosphere-ocean-sea ice systems has only recently become available, with previous skill evaluations mainly limited to area-integrated quantities. Here we show, based on a large set of retrospective ensemble model forecasts, that a dynamical forecast system produces skillful seasonal forecasts of local sea ice retreat and advance dates - variables that are of great interest to a wide range of end users. Advance dates can generally be skillfully predicted at longer lead times ( 5 months on average) than retreat dates ( 3 months). The skill of retreat date forecasts mainly stems from persistence of initial sea ice anomalies, whereas advance date forecasts benefit from longer time scale and more predictable variability in ocean temperatures. These results suggest that further investments in the development of dynamical seasonal forecast systems may result in significant socioeconomic benefits.

  11. Offshore produced water management: A review of current practice and challenges in harsh/Arctic environments.

    Science.gov (United States)

    Zheng, Jisi; Chen, Bing; Thanyamanta, Worakanok; Hawboldt, Kelly; Zhang, Baiyu; Liu, Bo

    2016-03-15

    Increasing offshore oil and gas exploration and development in harsh/Arctic environments require more effective offshore produced water management, as these environments are much more sensitive to changes in water quality than more temperate climates. However, the number and scope of studies of offshore produced water management in harsh/Arctic environments are limited. This paper reviews the current state of offshore produced water management, impacts, and policies, as well as the vulnerability, implications and operational challenges in harsh/Arctic environments. The findings show that the primary contaminant(s) of concern are contained in both the dissolved oil and the dispersed oil. The application of emerging technologies that can tackle this issue is significantly limited by the challenges of offshore operations in harsh/Arctic environments. Therefore, there is a need to develop more efficient and suitable management systems since more stringent policies are being implemented due to the increased vulnerability of harsh/Arctic environments.

  12. A simulation-based probabilistic design method for arctic sea transport systems

    Science.gov (United States)

    Martin, Bergström; Ove, Erikstad Stein; Sören, Ehlers

    2016-12-01

    When designing an arctic cargo ship, it is necessary to consider multiple stochastic factors. This paper evaluates the merits of a simulation-based probabilistic design method specifically developed to deal with this challenge. The outcome of the paper indicates that the incorporation of simulations and probabilistic design parameters into the design process enables more informed design decisions. For instance, it enables the assessment of the stochastic transport capacity of an arctic ship, as well as of its long-term ice exposure that can be used to determine an appropriate level of ice-strengthening. The outcome of the paper also indicates that significant gains in transport system cost-efficiency can be obtained by extending the boundaries of the design task beyond the individual vessel. In the case of industrial shipping, this allows for instance the consideration of port-based cargo storage facilities allowing for temporary shortages in transport capacity and thus a reduction in the required fleet size / ship capacity.

  13. A Simulation-Based Probabilistic Design Method for Arctic Sea Transport Systems

    Institute of Scientific and Technical Information of China (English)

    Bergstrm Martin; Erikstad Stein Ove; and Ehlers Sren

    2016-01-01

    When designing an arctic cargo ship, it is necessary to consider multiple stochastic factors. This paper evaluates the merits of a simulation-based probabilistic design method specifically developed to deal with this challenge. The outcome of the paper indicates that the incorporation of simulations and probabilistic design parameters into the design process enables more informed design decisions. For instance, it enables the assessment of the stochastic transport capacity of an arctic ship, as well as of its long-term ice exposure that can be used to determine an appropriate level of ice-strengthening. The outcome of the paper also indicates that significant gains in transport system cost-efficiency can be obtained by extending the boundaries of the design task beyond the individual vessel. In the case of industrial shipping, this allows for instance the consideration of port-based cargo storage facilities allowing for temporary shortages in transport capacity and thus a reduction in the required fleet size / ship capacity.

  14. Precambrian evolution of the climate system.

    Science.gov (United States)

    Walker, J C

    1990-01-01

    Climate is an important environmental parameter of the early Earth, likely to have affected the origin and evolution of life, the composition and mineralogy of sedimentary rocks, and stable isotope ratios in sedimentary minerals. There is little observational evidence constraining Precambrian climates. Most of our knowledge is at present theoretical. Factors that must have affected the climate include reduced solar luminosity, enhanced rotation rate of the Earth, an area of land that probably increased with time, and biological evolution, particularly as it affected the composition of the atmosphere and the greenhouse effect. Cloud cover is a major uncertainty about the early Earth. Carbon dioxide and its greenhouse effect are the factors that have been most extensively studied. This paper presents a new examination of the biogeochemical cycles of carbon as they may have changed between an Archean Earth deficient in land, sedimentary rocks, and biological activity, and a Proterozoic Earth much like the modern Earth, but lacking terrestrial life and carbonate-secreting plankton. Results of a numerical simulation of this transition show how increasing biological activity could have drawn down atmospheric carbon dioxide by extracting sedimentary organic carbon from the system. Increasing area of continents could further have drawn down carbon dioxide by encouraging the accumulation of carbonate sediments. An attempt to develop a numerical simulation of the carbon cycles of the Precambrian raises questions about sources and sinks of marine carbon and alkalinity on a world without continents. More information is needed about sea-floor weathering processes.

  15. Arctic Aerosols and Sources

    DEFF Research Database (Denmark)

    Nielsen, Ingeborg Elbæk

    2017-01-01

    Since the Industrial Revolution, the anthropogenic emission of greenhouse gases has been increasing, leading to a rise in the global temperature. Particularly in the Arctic, climate change is having serious impact where the average temperature has increased almost twice as much as the global during...

  16. Climate Model Diagnostic Analyzer Web Service System

    Science.gov (United States)

    Lee, S.; Pan, L.; Zhai, C.; Tang, B.; Jiang, J. H.

    2013-12-01

    The latest Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report stressed the need for the comprehensive and innovative evaluation of climate models with newly available global observations. The traditional approach to climate model evaluation, which compares a single parameter at a time, identifies symptomatic model biases and errors but fails to diagnose the model problems. The model diagnosis process requires physics-based multi-variable comparisons that typically involve large-volume and heterogeneous datasets, making them both computationally- and data-intensive. To address these challenges, we are developing a parallel, distributed web-service system that enables the physics-based multi-variable model performance evaluations and diagnoses through the comprehensive and synergistic use of multiple observational data, reanalysis data, and model outputs. We have developed a methodology to transform an existing science application code into a web service using a Python wrapper interface and Python web service frameworks (i.e., Flask, Gunicorn, and Tornado). The web-service system, called Climate Model Diagnostic Analyzer (CMDA), currently supports (1) all the datasets from Obs4MIPs and a few ocean datasets from NOAA and Argo, which can serve as observation-based reference data for model evaluation and (2) many of CMIP5 model outputs covering a broad range of atmosphere, ocean, and land variables from the CMIP5 specific historical runs and AMIP runs. Analysis capabilities currently supported by CMDA are (1) the calculation of annual and seasonal means of physical variables, (2) the calculation of time evolution of the means in any specified geographical region, (3) the calculation of correlation between two variables, and (4) the calculation of difference between two variables. A web user interface is chosen for CMDA because it not only lowers the learning curve and removes the adoption barrier of the tool but also enables instantaneous use

  17. DOI/GTN-P Climate and active-layer data acquired in the National Petroleum Reserve–Alaska and the Arctic National Wildlife Refuge, 1998–2014

    Science.gov (United States)

    Urban, Frank E.; Clow, Gary D.

    2016-03-04

    This report provides data collected by the climate monitoring array of the U.S. Department of the Interior on Federal lands in Arctic Alaska over the period August 1998 to July 2014; this array is part of the Global Terrestrial Network for Permafrost (DOI/GTN-P). In addition to presenting data, this report also describes monitoring, data collection, and quality-control methods. The array of 16 monitoring stations spans lat 68.5°N. to 70.5°N. and long 142.5°W. to 161°W., an area of approximately 150,000 square kilometers. Climate summaries are presented along with quality-controlled data. Data collection is ongoing and includes the following climate- and permafrost-related variables: air temperature, wind speed and direction, ground temperature, soil moisture, snow depth, rainfall totals, up- and downwelling shortwave radiation, and atmospheric pressure. These data were collected by the U.S. Geological Survey in close collaboration with the Bureau of Land Management and the U.S. Fish and Wildlife Service.

  18. DOI/GTN-P Climate and active-layer data acquired in the National Petroleum Reserve–Alaska and the Arctic National Wildlife Refuge, 1998–2015

    Science.gov (United States)

    Urban, Frank E.; Clow, Gary D.

    2017-02-06

    This report provides data collected by the climate monitoring array of the U.S. Department of the Interior on Federal lands in Arctic Alaska over the period August 1998 to July 2015; this array is part of the Global Terrestrial Network for Permafrost (DOI/GTN-P). In addition to presenting data, this report also describes monitoring, data collection, and quality-control methods. The array of 16 monitoring stations spans lat 68.5°N. to 70.5°N. and long 142.5°W. to 161°W., an area of approximately 150,000 square kilometers. Climate summaries are presented along with quality-controlled data. Data collection is ongoing and includes the following climate- and permafrost-related variables: air temperature, wind speed and direction, ground temperature, soil moisture, snow depth, rainfall totals, up- and downwelling shortwave radiation, and atmospheric pressure. These data were collected by the U.S. Geological Survey in close collaboration with the Bureau of Land Management and the U.S. Fish and Wildlife Service.

  19. DOI/GTN-P climate and active-layer data acquired in the National Petroleum Reserve: Alaska and the Arctic National Wildlife Refuge, 1998-2011

    Science.gov (United States)

    Urban, Frank E.; Clow, Gary D.

    2014-01-01

    This report provides data collected by the climate monitoring array of the U.S. Department of the Interior on Federal lands in Arctic Alaska over the period August 1998 to July 2011; this array is part of the Global Terrestrial Network for Permafrost, (DOI/GTN-P). In addition to presenting data, this report also describes monitoring, data collection, and quality-control methodology. This array of 16 monitoring stations spans lat 68.5°N. to 70.5°N. and long 142.5°W. to 161°W., an area of approximately 150,000 square kilometers. Climate summaries are presented along with quality-controlled data. Data collection is ongoing and includes the following climate- and permafrost-related variables: air temperature, wind speed and direction, ground temperature and soil moisture, snow depth, rainfall, up- and downwelling shortwave radiation, and atmospheric pressure. These data were collected by the U.S. Geological Survey in close collaboration with the Bureau of Land Management and the U.S. Fish and Wildlife Service.

  20. DOI/GTN-P climate and active-layer data acquired in the National Petroleum Reserve-Alaska and the Arctic National Wildlife Refuge

    Science.gov (United States)

    Urban, Frank E.; Clow, Gary D.

    2014-01-01

    This report provides data collected by the climate monitoring array of the U.S. Department of the Interior on Federal lands in Arctic Alaska over the period August 1998 to July 2013; this array is part of the Global Terrestrial Network for Permafrost, (DOI/GTN-P). In addition to presenting data, this report also describes monitoring, data collection, and quality-control methods. This array of 16 monitoring stations spans lat 68.5°N. to 70.5°N. and long 142.5°W. to 161°W., an area of approximately 150,000 square kilometers. Climate summaries are presented along with quality-controlled data. Data collection is ongoing and includes the following climate- and permafrost-related variables: air temperature, wind speed and direction, ground temperature, soil moisture, snow depth, rainfall totals, up- and downwelling shortwave radiation, and atmospheric pressure. These data were collected by the U.S. Geological Survey in close collaboration with the Bureau of Land Management and the U.S. Fish and Wildlife Service.

  1. High resolution modeling of the upper troposphere and lower stratosphere region over the Arctic - GEM-AC simulations for the future climate with and without aviation emissions.

    Science.gov (United States)

    Porebska, Magdalena; Struzewska, Joanna; Kaminski, Jacek W.

    2016-04-01

    Upper troposphere and lower stratosphere (UTLS) region is a layer around the tropopause. Perturbation of the chemical composition in the UTLS region can impact physical and dynamical processes that can lead to changes in cloudiness, precipitation, radiative forcing, stratosphere-troposphere exchange and zonal flow. The objective of this study is to investigate the potential impacts of aviation emissions on the upper troposphere and lower stratosphere. In order to assess the impact of the aviation emissions we will focus on changes in atmospheric dynamic due to changes in chemical composition in the UTLS over the Arctic. Specifically, we will assess perturbations in the distribution of the wind, temperature and pressure fields in the UTLS region. Our study will be based on simulations using a high resolution chemical weather model for four scenarios of current (2006) and future (2050) climate: with and without aircraft emissions. The tool that we use is the GEM-AC (Global Environmental Multiscale with Atmospheric Chemistry) chemical weather model where air quality, free tropospheric and stratospheric chemistry processes are on-line and interactive in an operational weather forecast model of Environment Canada. In vertical, the model domain is defined on 70 hybrid levels with model top at 0.1 mb. The gas-phase chemistry includes detailed reactions of Ox, NOx, HOx, CO, CH4, ClOx and BrO. Also, the model can address aerosol microphysics and gas-aerosol partitioning. Aircraft emissions are from the AEDT 2006 database developed by the Federal Aviation Administration (USA) and the future climate simulations are based on RCP8.5 projection presented by the IPCC in the fifth Assessment Report AR5. Results from model simulations on a global variable grid with 0.5o x 0.5o uniform resolution over the Arctic will be presented.

  2. Creating future fit between ice and society: The institutionalization of a refuge in the Arctic to preserve sea ice system services in a changing North

    Science.gov (United States)

    Lovecraft, A. L.; Meek, C. L.

    2010-12-01

    The Arctic sea ice system can be holistically characterized as a social-ecological system that provides not only vital geophysical and biological services to climate and oceans but also provisioning services to people and industry. These services are under threat from the three major interconnected global forces of increasing traffic for shipping, security, and tourism; contaminant accumulation primarily from distant, but also related to some local marine activities, industrial production; and climatic changes, especially the warming at the poles which is diminishing the earth’s cryosphere. As the Arctic becomes more open due to sea ice loss the current strategies to preserve individual species or sea ice system functions may become obsolete in the next several decades. Concurrent to this will be the rise of traffic in areas currently not passable and an increase in exploitation of natural resources (biological and mineral) further north. This expansion of human activity does not have a suite of institutions in place that comprehensively address a future open Arctic Ocean and the coasts of the circumpolar north. Consequently, as the amount of space that can preserve a diversity of sea ice system services shrinks and the use of that space becomes crowded with interests, governments across scales need to be able to plan to balance the increase in use with preservation of services valuable both in terms of regulating and supporting planetary processes and the cultural and provisioning services more immediately tied to human flourishing. In short, it is a race between stressors and human capacity to manage them through rules minimizing their direct impact on the ice or preventing them from entering an eventual “ice shed” boundaries of a minimum summer sea ice cover. This poster explores the potential for the creation of a system of governance that would provide a refuge based on the projected summer sea ice to remain in the Arctic even as the climate shifts in

  3. Teachers, Researchers, and Students Collaborating in Arctic Climate Change Research: The Partnership Between the Svalbard REU and ARCUS PolarTREC programs

    Science.gov (United States)

    Roof, S.; Warburton, J.; Oddo, B.; Kane, M.

    2007-12-01

    Since 2004, the Arctic Research Consortium of the U.S. (ARCUS) "TREC" program (Teachers and Researchers Exploring and Collaborating, now "PolarTREC") has sent four K-12 teachers to Svalbard, Norway to work alongside researchers and u