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  1. Characterization of meltwater 'ingredients' at the Haig Glacier, Canadian Rockies: the importance of glaciers to regional water resources

    Science.gov (United States)

    Miller, K.; Marshall, S.

    2017-12-01

    With rising temperatures, Alberta's glaciers are under stresses which change and alter the timing, amount, and composition of meltwater contributions to rivers that flow from the Rocky Mountains. Meltwater can be stored within a glacier or it can drain through the groundwater system, reducing and delaying meltwater delivery to glacier-fed streams. This study tests whether the glacier meltwater is chemically distinct from rain or snow melt, and thus whether meltwater contributions to higher-order streams that flow from the mountains can be determined through stream chemistry. Rivers like the Bow, North Saskatchewan, and Athabasca are vital waterways for much of Alberta's population. Assessing the extent of glacier meltwater is vital to future water resource planning. Glacier snow/ice and meltwater stream samples were collected during the 2017 summer melt season (May- September) and analyzed for isotope and ion chemistry. The results are being used to model water chemistry evolution in the melt stream through the summer season. A chemical mixing model will be constructed to determine the fractional contributions to the Haig meltwater stream from precipitation, surface melt, and subglacial meltwaters. Distinct chemical water signatures have not been used to partition water sources and understand glacier contributions to rivers in the Rockies. The goal of this work is to use chemical signatures of glacial meltwater to help assess the extent of glacier meltwater in Alberta rivers and how this varies through the summer season.

  2. Irreversible mass loss of Canadian Arctic Archipelago glaciers

    NARCIS (Netherlands)

    Lenaerts, J.T.M.|info:eu-repo/dai/nl/314850163; van Angelen, J.H.|info:eu-repo/dai/nl/325922470; van den Broeke, M.R.|info:eu-repo/dai/nl/073765643; Gardner, A.S.; Wouters, Bert|info:eu-repo/dai/nl/304120146; van Meijgaard, E.

    2013-01-01

    The Canadian Arctic Archipelago (CAA) contains the largest volume of glacier ice on Earth outside of Antarctica and Greenland. In the absence of significant calving, CAA glacier mass balance is governed by the difference between surface snow accumulation and meltwater runoff—surface mass balance.

  3. Limber pine health in the Canadian Rockies

    Science.gov (United States)

    Cyndi M. Smith; David Langor; Colin Myrholm; Jim Weber; Cameron Gillies; Jon Stuart-Smith

    2011-01-01

    Limber pine (Pinus flexilis) reaches the northern limit of its range at about 52 degrees latitude in Alberta (AB) and 51 degrees latitude in British Columbia (BC). Most populations are found on the eastern slopes of the Rocky Mountains, with a few disjunct populations west of the Continental Divide in southeastern BC.

  4. A revised Canadian perspective: progress in glacier hydrology

    Science.gov (United States)

    Munro, D. Scott

    2005-01-01

    Current research into glacier hydrology is occurring at a time when glaciers around the world, particularly those whose hydrological regimes affect populated areas, are shrinking as they go through a state of perpetual negative annual mass balance. Small glaciers alone are likely to contribute 0·5 to 1 mm year-1 to global sea-level rise, with associated reductions in local freshwater resources, impacts upon freshwater ecosystems and increased risk of hazard due to outburst floods. Changes to the accumulation regimes of glaciers and ice sheets may be partly responsible, so the measurement and distribution of snowfall in glacierized basins, a topic long represented in non-glacierized basin research, is now beginning to receive more attention than it did before, aided by the advent of reliable automatic weather stations that provide data throughout the year. Satellite data continue to be an important information source for summer meltwater estimation, as distributed models, and their need for albedo maps, continue to develop. This further entails the need for simplifications to energy balance components, sacrificing point detail so that spatial calculation may proceed more quickly. The understanding of surface meltwater routing through the glacier to produce stream outflow continues to be a stimulating area of research, as demonstrated by activity at the Trapridge Glacier, Canada, and Canadian involvement in the Haut Glacier d'Arolla, Switzerland. As Canadian glacier monitoring continues to evolve, effort must be directed toward developing situations where mass balance, meltwater generation and flow routing studies can be done together at selected sites. Copyright

  5. Canadian Rockies Ecoregion: Chapter 4 in Status and trends of land change in the Western United States--1973 to 2000

    Science.gov (United States)

    Taylor, Janis L.

    2012-01-01

    The Canadian Rockies Ecoregion covers approximately 18,494 km2 (7,141 mi2) in northwestern Montana (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The east side of the ecoregion is bordered by the Montana Valley and Foothill Prairies Ecoregion, which also forms a large part of the western border of the ecoregion. In addition, the Northern Rockies Ecoregion wraps around the ecoregion to the northwest and south (fig. 1). As the name implies, the Canadian Rocky Mountains are located mostly in Canada, straddling the border between Alberta and British Columbia. However, this ecoregion only includes the part of the northern Rocky Mountains that is in the United States. This ecoregion is characterized by steep, high-elevation mountain ranges similar to most of the rest of the Rocky Mountains. Compared to the Northern Rockies Ecoregion, however, the Canadian Rockies Ecoregion reaches higher elevations and contains a greater proportion of perennial snow and ice (Omernik, 1987) (fig. 2). Over the years, this section of the Rocky Mountains has garnered many different names, including “Crown of the Continent” by George Bird Grinnell (Waldt, 2008) and “Backbone of the World” by the Blackfeet (Pikuni) Nation. Throughout the ecoregion, montane, subalpine, and alpine ecosystems have distinct flora and fauna elevation zones. Glaciers, permanent snowfields, and seasonal snowpack are found at the highest elevations. Spring and summer runoff fills lakes and tarns that form the headwaters of numerous streams and rivers, including the Columbia and Missouri Rivers that flow west and east, respectively, from the Continental Divide.

  6. Landscape and climate change in the central Canadian Rockies during the 20. century

    Energy Technology Data Exchange (ETDEWEB)

    Luckman, B. H. [Western Ontario Univ., Dept. of Geography, London, ON (Canada)

    1998-12-31

    Selected evidence of environmental changes in the central Canadian Rocky Mountains region during the 20. century are reviewed. Climatic records show an annual mean temperature rise of 1.4 degrees C over the last 100 years. Greatest increases have been in winter temperatures (3.2 degrees C/century). Precipitation changes also varied considerably with generally highest flows in the mid-20. century. A tree-ring based temperature reconstruction indicates summer and spring temperatures in the last half of the 20. century higher than any equivalent period over the last 900 years. Glaciers are estimated to have lost 25 per cent of their area in the last 100 years. It is believed that they are smaller now than at any time in the last 3000 years. These two lines of evidence indicate that the climate of the late 20. century is exceptional when viewed in the context of the last one to three millenia. Changes in vegetation also have been observed at the upper treeline ecotone in response to climate changes over the last century, but the most significant change in the last 100 years is the transformation of the character of the montane forest due to reduction in forest fire frequency, resulting from an active policy of fire suppression. 81 refs., 4 tabs., 7 figs.

  7. Summer temperatures in the Canadian Rockies during the last millennium: a revised record

    Energy Technology Data Exchange (ETDEWEB)

    Luckman, B.H. [University of Western Ontario, Department of Geography, London, Ontario (Canada); Wilson, R.J.S. [Edinburgh University, School of GeoSciences, Grant Institute, Edinburgh (United Kingdom)

    2005-02-01

    We present a significant update to a millennial summer temperature reconstruction (1073-1983) that was originally published in 1997. Utilising new tree-ring data (predominantly Picea engelmannii), the reconstruction is not only better replicated, but has been extended (950-1994) and is now more regionally representative. Calibration and verification statistics were improved, with the new model explaining 53% of May-August maximum temperature variation compared to the original (39% of April-August mean temperatures). The maximum latewood density data, which are weighted more strongly in the regression model than ringwidth, were processed using regional curve standardisation to capture potential centennial to millennial scale variability. The reconstruction shows warm intervals, comparable to twentieth century values, for the first half of the eleventh century, the late 1300s and early 1400s. The bulk of the record, however, is below the 1901-1980 normals, with prolonged cool periods from 1200 to 1350 and from 1450 to the late 19th century. The most extreme cool period is observed to be in the 1690s. These reconstructed cool periods compare well with known regional records of glacier advances between 1150 and the 1300s, possibly in the early 1500s, early 1700s and 1800s. Evidence is also presented of the influence of solar activity and volcanic events on summer temperature in the Canadian Rockies over the last 1,000 years. Although this reconstruction is regional in scope, it compares well at multi-decadal to centennial scales with Northern Hemisphere temperature proxies and at millennial scales with reconstructions that were also processed to capture longer timescale variability. This coherence suggests that this series is globally important for the assessment of natural temperature variability over the last 1,000 years. (orig.)

  8. Grizzly bears as a filter for human use management in Canadian Rocky Mountain national parks

    Science.gov (United States)

    Derek Petersen

    2000-01-01

    Canadian National Parks within the Rocky Mountains recognize that human use must be managed if the integrity and health of the ecosystems are to be preserved. Parks Canada is being challenged to ensure that these management actions are based on credible scientific principles and understanding. Grizzly bears provide one of only a few ecological tools that can be used to...

  9. Glaciers

    Science.gov (United States)

    Hambrey, Michael; Alean, Jürg

    2004-12-01

    Glaciers are among the most beautiful natural wonders on Earth, as well as the least known and understood, for most of us. Michael Hambrey describes how glaciers grow and decay, move and influence human civilization. Currently covering a tenth of the Earth's surface, glacier ice has shaped the landscape over millions of years by scouring away rocks and transporting and depositing debris far from its source. Glacier meltwater drives turbines and irrigates deserts, and yields mineral-rich soils as well as a wealth of valuable sand and gravel. However, glaciers also threaten human property and life. Our future is indirectly connected with the fate of glaciers and their influence on global climate and sea level. Including over 200 stunning photographs, the book takes the reader from the High-Arctic through North America, Europe, Asia, Africa, New Zealand and South America to the Antarctic. Michael Hambrey is Director of the Centre for Glaciology at the University of Wales, Aberystwyth. A past recipient of the Polar Medal, he was also given the Earth Science Editors' Outstanding Publication Award for the first edition of Glaciers (Cambridge, 1995). Hambrey is also the author of Glacial Environments (British Columbia, 1994). JÜrg Alean is Professor of Geography at the Kantonsschule ZÜrcher Unterland in BÜlach, Switzerland.

  10. Sharply increased mass loss from glaciers and ice caps in the Canadian Arctic Archipelago.

    Science.gov (United States)

    Gardner, Alex S; Moholdt, Geir; Wouters, Bert; Wolken, Gabriel J; Burgess, David O; Sharp, Martin J; Cogley, J Graham; Braun, Carsten; Labine, Claude

    2011-05-19

    Mountain glaciers and ice caps are contributing significantly to present rates of sea level rise and will continue to do so over the next century and beyond. The Canadian Arctic Archipelago, located off the northwestern shore of Greenland, contains one-third of the global volume of land ice outside the ice sheets, but its contribution to sea-level change remains largely unknown. Here we show that the Canadian Arctic Archipelago has recently lost 61 ± 7 gigatonnes per year (Gt yr(-1)) of ice, contributing 0.17 ± 0.02 mm yr(-1) to sea-level rise. Our estimates are of regional mass changes for the ice caps and glaciers of the Canadian Arctic Archipelago referring to the years 2004 to 2009 and are based on three independent approaches: surface mass-budget modelling plus an estimate of ice discharge (SMB+D), repeat satellite laser altimetry (ICESat) and repeat satellite gravimetry (GRACE). All three approaches show consistent and large mass-loss estimates. Between the periods 2004-2006 and 2007-2009, the rate of mass loss sharply increased from 31 ± 8 Gt yr(-1) to 92 ± 12 Gt yr(-1) in direct response to warmer summer temperatures, to which rates of ice loss are highly sensitive (64 ± 14 Gt yr(-1) per 1 K increase). The duration of the study is too short to establish a long-term trend, but for 2007-2009, the increase in the rate of mass loss makes the Canadian Arctic Archipelago the single largest contributor to eustatic sea-level rise outside Greenland and Antarctica.

  11. Prevalence of antibodies to canine parvovirus and distemper virus in wolves in the Canadian Rocky Mountains.

    Science.gov (United States)

    Nelson, Brynn; Hebblewhite, Mark; Ezenwa, Vanessa; Shury, Todd; Merrill, Evelyn H; Paquet, Paul C; Schmiegelow, Fiona; Seip, Dale; Skinner, Geoff; Webb, Nathan

    2012-01-01

    Wild carnivores are often exposed to diseases via contact with peridomestic host species that travel through the wildland-urban interfaces. To determine the antibody prevalences and relationships to human activity for two common canid pathogens, we sampled 99 wolves (Canis lupus) from 2000 to 2008 for antibodies to canine parvovirus (CPV) and canine distemper virus (CDV) in Banff and Jasper National Parks and surrounding areas of the Canadian Rockies. This population was the source for wolves reintroduced into the Northern Rockies of the US. Of 99 wolves sampled, 94 had detectable antibody to CPV (95%), 24 were antibody-positive for CDV (24%), and 24 had antibodies to both pathogens (24%). We tested whether antibody prevalences for CPV and CDV were higher closer to human activity (roads, town sites, First Nation reserves) and as a function of sex and age class. Wolves ≥2 yr old were more likely to be have antibodies to CPV. For CDV, male wolves, wolves ≥2 yr, and those closer to First Nation reserves were more likely to have antibodies. Overall, however, we found minimal support for human influence on antibody prevalence for CDV and CPV. The similarity between our antibody prevalence results and results from recent studies in Yellowstone National Park suggests that at least in the case of CDV, and perhaps CPV, these could be important pathogens with potential effects on wolf populations.

  12. Conditions for caribou persistence in the wolf-elk-caribou systems of the Canadian Rockies

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    Mark Hebblewhite

    2007-04-01

    Full Text Available Woodland caribou populations are considered threatened in Alberta and have declined in the Canadian Rocky Mountain National Parks of Banff and Jasper despite protection from factors causing caribou populations to decline outside of parks. Recent research emphasizes the importance of the numeric response of wolves to moose in moose-caribou-wolf systems to caribou persistence. Moose are rare in the Canadian Rockies, where the dominant ungulate prey for wolves is elk. Few studies have explored wolf-elk dynamics and none have examined implications for caribou. We used data collected in Banff to estimate the numeric response of wolves to elk from 1985 to 2005. Because no caribou kill-rate data exist for the Rockies, we explore the consequences of a range of hypothetical kill-rates based on kill-rates of alternate prey collected from 1985 to 2000 in Banff. We then multiplied the numeric response of wolves by the estimated caribou kill-rates to estimate the wolf predation response on caribou as a function of elk density. Caribou predation rates were inversely density dependent because wolf numbers depend on prey species besides caribou in multiple prey species systems. We then combined this simple wolf-elk-caribou model with observed demographic and population estimates for Banff and Jasper caribou from 2003-2004 and solved for the critical kill-rate thresholds above which caribou populations would decline. Using these critical kill-rate thresholds, Jasper caribou are likely to persist when wolf densities are below 2.1 - 4.3 wolves/1000km2 and/or when elk densities are below 0.015- 0.033 elk/km2. Thresholds for Banff caribou persistence are much lower because of inverse density dependence. Future research is needed on some of the necessary assumptions underlying our modeling including multi-prey wolf numeric responses, wolf kill-rates of caribou, caribou mortality by other predators, and spatial aspects of wolf-elk-caribou dynamics.

  13. Factors influencing spring and summer areal snow ablation and snowcover depletion in alpine terrain: detailed measurements from the Canadian Rockies

    OpenAIRE

    Schirmer, Michael; Pomeroy, John W.

    2018-01-01

    The spatial distribution of snow water equivalent (SWE) and melt are important to estimating areal melt rates and snowcover depletion dynamics but are rarely measured in detail during the late ablation period. This study contributes the result of high resolution observations made using large numbers of sequential aerial photographs taken from an Unmanned Aerial Vehicle on an alpine ridge in the Fortress Mountain Snow Laboratory in the Canadian Rocky Mountains from May to July. With Structure-...

  14. Quantification of controls on regional rockfall activity and talus deposition, Kananaskis, Canadian Rockies

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    Thapa, Prasamsa; Martin, Yvonne E.; Johnson, E. A.

    2017-12-01

    Rockfall is a significant geomorphic process in many mountainous regions that also poses a notable natural hazard risk. Most previous studies of rockfall erosion have investigated the mechanics and rates of local rockwall retreat and talus deposition, with only a few investigations of rockfall and/or associated talus considering larger spatial scales (i.e., drainage basin, mountain range). The purpose of the current research is to investigate the areal extent of rockfall-talus and controlling factors of its distribution over regional spatial scales (of order 102 km2) in Kananaskis, Canadian Rockies to inform our understanding of its significance in mountain development. To achieve this goal, a large talus inventory is collected and analyzed for 11 steep tributaries of the Kananaskis River, Canadian Rockies. Talus accumulations associated with rockfall provide evidence about the nature and rates of rockfall activity that supplies sediment to these deposits and are the focus of the present study. To quantify the controls of rockfall-talus activity in this region, we analyze the association of talus deposits with structural geology, glacial topography, and temperature-related weathering (i.e., frost cracking). A total of 324 talus polygons covering a surface area of 28.51 km2 are delineated within the 11 study basins, with the number of talus polygons in each study basin ranging from 1 to 73. Analysis of the talus inventory shows that cirques and glacially sculpted valleys are locations of notable talus accumulation in Kananaskis, with other locations of significant talus deposition being associated with thrust faults. We also found that the upper elevations at which talus deposits are typically found are the general range of elevations experiencing a notable number of days in the frost cracking window when this window is defined as - 3 to - 15 °C; no such association is found for the frost cracking window of - 3 to - 8 °C. Estimates of average erosion rates for all

  15. Development of monitoring protocols to detect change in rocky intertidal communities of Glacier Bay National Park and Preserve

    Science.gov (United States)

    Irvine, Gail V.

    2010-01-01

    Glacier Bay National Park and Preserve in southeastern Alaska includes extensive coastlines representing a major proportion of all coastlines held by the National Park Service. The marine plants and invertebrates that occupy intertidal shores form highly productive communities that are ecologically important to a number of vertebrate and invertebrate consumers and that are vulnerable to human disturbances. To better understand these communities and their sensitivity, it is important to obtain information on species abundances over space and time. During field studies from 1997 to 2001, I investigated probability-based rocky intertidal monitoring designs that allow inference of results to similar habitat within the bay and that reduce bias. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope less than or equal to 30 degrees was rare. This finding illustrated the value of probability-based surveys and led to a shift in the target habitat type to more mixed rocky habitat with steeper slopes. Subsequently, I investigated different sampling methods and strategies for their relative power to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles -Balanomorpha, the mussel Mytilus trossulus and the rockweed Fucus distichus subsp. evanescens. I found that lower-intensity sampling of 25 randomly selected sites (= coarse-grained sampling) provided a greater ability to detect changes in the abundances of these taxa than did more intensive sampling of 6 sites (= fine-grained sampling). Because of its greater power, the coarse-grained sampling scheme was adopted in subsequent years. This report provides detailed analyses of the 4 years of data and evaluates the relative effect of different sampling attributes and management-set parameters on the ability of the sampling to detect changes in the abundances of these taxa. The intent was to provide managers with information

  16. Interplay between field observations and numerical modeling to understand temporal pulsing of tree root throw processes, Canadian Rockies, Canada

    Science.gov (United States)

    Martin, Y. E.; Johnson, E. A.; Chaikina, O.

    2013-10-01

    During the cycle of forest disturbance, regeneration, and maturity, tree mortality leading to topple is a regular occurrence. When tree topple occurs relatively soon after mortality and if the tree has attained some threshold diameter at breast height (dbh) at the time of death, then notable amounts of soil may be upheaved along with the root wad. This upheaval may result in sediment transfers and soil production. A combination of field evidence and numerical modeling is used herein to gain insights regarding the temporal dynamics of tree topple, associated root throw processes, and pit-mound microtopography. Results from our model of tree population dynamics demonstrate temporal patterns in root throw processes in subalpine forests of the Canadian Rockies, a region in which forests are affected largely by wildfire disturbance. As the forest regenerates after disturbance, the new cohort of trees has to reach a critical dbh before significant root plate upheaval can occur; in the subalpine forests of the Canadian Rockies, this may take up to ~ 102 years. Once trees begin to reach this critical dbh for root plate upheaval, a period of sporadic root throw arises that is caused by mortality of trees during competition. In due course, another wildfire will occur on the landscape and a period of much increased root throw activity then takes place for the next several decades; tree sizes and, therefore, the amount of sediment disturbance will be greater the longer the time period since the previous fire. Results of previous root throw studies covering a number of regional settings are used to guide an exercise in diffusion modeling with the aim of defining a range of reasonable diffusion coefficients for pit-mound degradation; the most appropriate values to fit the field data ranged from 0.01 m2 y- 1 to 0.1 m2 y- 1. A similar exercise is then undertaken that is guided by our field observations in subalpine forests of the Canadian Rockies. For these forests, the most

  17. Patterns of LGM precipitation in the U.S. Rocky Mountains: results from regional application of a glacier mass/energy balance and flow model

    Science.gov (United States)

    Leonard, E. M.; Laabs, B. J.; Refsnider, K. A.; Plummer, M. A.; Jacobsen, R. E.; Wollenberg, J. A.

    2010-12-01

    Global climate model (GCM) simulations of the last glacial maximum (LGM) in the western United States predict changes in atmospheric circulation and storm tracks that would have resulted in significantly less-than-modern precipitation in the Northwest and northern Rockies, and significantly more-than-modern precipitation in the Southwest and southern Rockies. Model simulations also suggest that late Pleistocene pluvial lakes in the intermontane West may have modified local moisture regimes in areas immediately downwind. In this study, we present results of the application of a coupled energy/mass balance and glacier-flow model (Plummer and Phillips, 2003) to reconstructed paleoglaciers in Rocky Mountains of Utah, New Mexico, Colorado, and Wyoming to assess the changes from modern climate that would have been necessary to sustain each glacier in mass-balance equilibrium at its LGM extent. Results demonstrate that strong west-to-east and north-to-south gradients in LGM precipitation, relative to present, would be required if a uniform LGM temperature depression with respect to modern is assumed across the region. At an assumed 7oC temperature depression, approximately modern precipitation would have been necessary to support LGM glaciation in the Colorado Front Range, significantly less than modern precipitation to support glaciation in the Teton Range, and almost twice modern precipitation to sustain glaciers in the Wasatch and Uinta ranges of Utah and the New Mexico Sangre de Cristo Range. The observed west-to-east (Utah-to-Colorado) LGM moisture gradient is consistent with precipitation enhancement from pluvial Lake Bonneville, decreasing with distance downwind from the lake. The north-to-south (Wyoming-to-New Mexico) LGM moisture gradient is consistent with a southward LGM displacement of the mean winter storm track associated with the winter position of the Pacific Jet Stream across the western U.S. Our analysis of paleoglacier extents in the Rocky Mountain

  18. Spatiotemporal variability of Canadian High Arctic glacier surface albedo from MODIS data, 2001-2016

    Science.gov (United States)

    Mortimer, Colleen A.; Sharp, Martin

    2018-02-01

    Inter-annual variations and longer-term trends in the annual mass balance of glaciers in Canada's Queen Elizabeth Islands (QEI) are largely attributable to changes in summer melt. The largest source of melt energy in the QEI in summer is net shortwave radiation, which is modulated by changes in glacier surface albedo. We used measurements from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors to investigate large-scale spatial patterns, temporal trends, and variability in the summer surface albedo of QEI glaciers from 2001 to 2016. Mean summer black-sky shortwave broadband albedo (BSA) decreased at a rate of 0.029±0.025 decade-1 over that period. Larger reductions in BSA occurred in July (-0.050±0.031 decade-1). No change in BSA was observed in either June or August. Most of the decrease in BSA, which was greatest at lower elevations around the margins of the ice masses, occurred between 2007 and 2012, when mean summer BSA was anomalously low. The first principal component of the 16-year record of mean summer BSA was well correlated with the mean summer North Atlantic Oscillation index, except in 2006, 2010, and 2016, when the mean summer BSA appears to have been dominated by the August BSA. During the period 2001-2016, the mean summer land surface temperature (LST) over the QEI glaciers and ice caps increased by 0.049±0.038 °C yr-1, and the BSA record was negatively correlated (r: -0.86) with the LST record, indicative of a positive ice-albedo feedback that would increase rates of mass loss from the QEI glaciers.

  19. Native legume transplant survivorship and subsequent seedling recruitment on unamended coal mine soils in the Canadian Rocky Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Smyth, C.R.

    1997-05-01

    Transplant survivorship, growth, and reproductive performance of several indigenous high-elevation legume species grown in unamended spoil were studied at three coal mines in the Canadian Rocky Mountains. Survivorship varied with species but was highest for Astragalus aboriginum (62%), Astragalus alpinus (73-57%), Astragalus vexilliflexus var. nubilus (73-63%), and Oxytropis sericea (77-62%). Mortality was greatest during the first two years for most species. The causes of transplant mortality are considered to be drought stress, deep-seated `frost-popping`/root exposure, and damage, for example, root exposure and destruction of meristematic tissues by foraging mammals such as bighorn sheep, mountain goats, grizzly bears, and marmots. Survivorship, growth, and reproductive activity were greatest at the two subalpine disturbances. Growth varied with species, but the greatest growth increments (height and diameter) were recorded during the first and second years. Reproductive activity for the Astragalus species began during the first year at one location but, in general, flowering and seed set did not begin until the second or third years. Recruitment from seed was small ({lt} 10/year). Several of these species appear to be suitable for revegetation of subalpine and alpine surface mine disturbances.

  20. The characterization of Helicobacter pylori DNA associated with ancient human remains recovered from a Canadian glacier.

    Directory of Open Access Journals (Sweden)

    Treena Swanston

    2011-02-01

    Full Text Available Helicobacter pylori is a gram-negative bacterium that colonizes the stomach of nearly half of the world's population. Genotypic characterization of H. pylori strains involves the analysis of virulence-associated genes, such as vacA, which has multiple alleles. Previous phylogenetic analyses have revealed a connection between modern H. pylori strains and the movement of ancient human populations. In this study, H. pylori DNA was amplified from the stomach tissue of the Kwäday Dän Ts'ìnchi individual. This ancient individual was recovered from the Samuel Glacier in Tatshenshini-Alsek Park, British Columbia, Canada on the traditional territory of the Champagne and Aishihik First Nations and radiocarbon dated to a timeframe of approximately AD 1670 to 1850. This is the first ancient H. pylori strain to be characterized with vacA sequence data. The Tatshenshini H. pylori strain has a potential hybrid vacA m2a/m1d middle (m region allele and a vacA s2 signal (s region allele. A vacA s2 allele is more commonly identified with Western strains, and this suggests that European strains were present in northwestern Canada during the ancient individual's time. Phylogenetic analysis indicated that the vacA m1d region of the ancient strain clusters with previously published novel Native American strains that are closely related to Asian strains. This indicates a past connection between the Kwäday Dän Ts'ìnchi individual and the ancestors who arrived in the New World thousands of years ago.

  1. Multi-variable evaluation of hydrological model predictions for a headwater basin in the Canadian Rocky Mountains

    Directory of Open Access Journals (Sweden)

    X. Fang

    2013-04-01

    Full Text Available One of the purposes of the Cold Regions Hydrological Modelling platform (CRHM is to diagnose inadequacies in the understanding of the hydrological cycle and its simulation. A physically based hydrological model including a full suite of snow and cold regions hydrology processes as well as warm season, hillslope and groundwater hydrology was developed in CRHM for application in the Marmot Creek Research Basin (~ 9.4 km2, located in the Front Ranges of the Canadian Rocky Mountains. Parameters were selected from digital elevation model, forest, soil, and geological maps, and from the results of many cold regions hydrology studies in the region and elsewhere. Non-calibrated simulations were conducted for six hydrological years during the period 2005–2011 and were compared with detailed field observations of several hydrological cycle components. The results showed good model performance for snow accumulation and snowmelt compared to the field observations for four seasons during the period 2007–2011, with a small bias and normalised root mean square difference (NRMSD ranging from 40 to 42% for the subalpine conifer forests and from 31 to 67% for the alpine tundra and treeline larch forest environments. Overestimation or underestimation of the peak SWE ranged from 1.6 to 29%. Simulations matched well with the observed unfrozen moisture fluctuation in the top soil layer at a lodgepole pine site during the period 2006–2011, with a NRMSD ranging from 17 to 39%, but with consistent overestimation of 7 to 34%. Evaluations of seasonal streamflow during the period 2006–2011 revealed that the model generally predicted well compared to observations at the basin scale, with a NRMSD of 60% and small model bias (1%, while at the sub-basin scale NRMSDs were larger, ranging from 72 to 76%, though overestimation or underestimation for the cumulative seasonal discharge was within 29%. Timing of discharge was better predicted at the Marmot Creek basin outlet

  2. Using UAV photogrammetry to study topographic change: application to Saskatchewan Glacier, Alberta, Canada

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    Meunier Cardinal, G.; Demuth, M. N.; Kinnard, C.

    2016-12-01

    Glaciers are an important source of fresh water in the headwaters of the Canadian Rocky Mountains, and ongoing climate warming could reduce their future hydrological contribution. Unmanned Aerial Vehicles UAVs) are an emergent technology that allow studying glacial processes with an unprecedented level of detail, but their usefulness for deriving accurate topographic data on glaciers has not yet been fully assessed. In this perspective we tested the use of a UAV platform to acquire images at a very high spatial resolution (using the Structure from Motion (SfM) algorithm. A detailed assessment of DEM errors was performed by cross-validation of an network of ground control points (GCPs) deployed on the glacier surface. The influence of checkpoint position in the network, border effects, number of photos calibrated and GPS accuracy were examined. Topographical changes were measured from the DEM difference and surface displacements estimated by applying feature tracking techniques to the orthomosaics. Further, the dominant scales of topographic spatial variability were examined using a semivariogram analysis of the DEMs. Results show that UAV-based photogrammetry is promising to further our understanding of high-resolution glacier surface processes and to perform repeat, on-demand monitoring of glacier changes, but their application on remote glaciers remains challenging.

  3. Insights into contaminant transport from unconventional oil and gas developments from analog system analysis of methane-bearing thermal springs in the northern Canadian Rocky Mountains

    Science.gov (United States)

    Ferguson, Grant; Grasby, Stephen E.

    2018-03-01

    Natural gas is currently being produced from shales of the Montney and Liard basins in western Canada. Production requires hydraulic fracturing due to the low permeability of the shales in the basins. Stratigraphically equivalent shales are present in the northern Canadian Rocky Mountains. Thermal springs with notable hydrocarbon concentrations occur where large-scale faults intersect the same shale units that are the focus of gas development, indicating that under certain circumstances, connection of deep fractured shales to the land surface is possible. To constrain these conditions, simulations were conducted for the spring with the highest hydrocarbon flux (Toad River Spring), results of which indicate that in order to supply sufficient water to a fault to support measurable advection, the effective permeability of the shales in these structurally deformed areas must be one to four orders of magnitude higher than in areas of active gas production to the east. The spatial scale of enhanced permeability is much greater than that which is achieved by hydraulic fracturing and the mechanism of maintaining high pressures at depth is more persistent in time. Examination of groundwater velocities suggests that upward migration of solutes from hydraulic fracturing may take decades to centuries. Results also indicate that any temperature anomaly will be associated with transport along a fault at such velocities. No such temperature anomaly has been documented in regions with unconventional oil and gas development to date. Such an anomaly would be diagnostic of a deep solute source.

  4. Daily temperature records from a mesonet in the foothills of the Canadian Rocky Mountains, 2005–2010

    Directory of Open Access Journals (Sweden)

    W. H. Wood

    2018-03-01

    Full Text Available Near-surface air temperatures were monitored from 2005 to 2010 in a mesoscale network of 230 sites in the foothills of the Rocky Mountains in southwestern Alberta, Canada. The monitoring network covers a range of elevations from 890 to 2880 m above sea level and an area of about 18 000 km2, sampling a variety of topographic settings and surface environments with an average spatial density of one station per 78 km2. This paper presents the multiyear temperature dataset from this study, with minimum, maximum, and mean daily temperature data available at https://doi.org/10.1594/PANGAEA.880611. In this paper, we describe the quality control and processing methods used to clean and filter the data and assess its accuracy. Overall data coverage for the study period is 91 %. We introduce a weather-system-dependent gap-filling technique to estimate the missing 9 % of data. Monthly and seasonal distributions of minimum, maximum, and mean daily temperature lapse rates are shown for the region.

  5. Daily temperature records from a mesonet in the foothills of the Canadian Rocky Mountains, 2005-2010

    Science.gov (United States)

    Wood, Wendy H.; Marshall, Shawn J.; Whitehead, Terri L.; Fargey, Shannon E.

    2018-03-01

    Near-surface air temperatures were monitored from 2005 to 2010 in a mesoscale network of 230 sites in the foothills of the Rocky Mountains in southwestern Alberta, Canada. The monitoring network covers a range of elevations from 890 to 2880 m above sea level and an area of about 18 000 km2, sampling a variety of topographic settings and surface environments with an average spatial density of one station per 78 km2. This paper presents the multiyear temperature dataset from this study, with minimum, maximum, and mean daily temperature data available at https://doi.org/10.1594/PANGAEA.880611" target="_blank">https://doi.org/10.1594/PANGAEA.880611. In this paper, we describe the quality control and processing methods used to clean and filter the data and assess its accuracy. Overall data coverage for the study period is 91 %. We introduce a weather-system-dependent gap-filling technique to estimate the missing 9 % of data. Monthly and seasonal distributions of minimum, maximum, and mean daily temperature lapse rates are shown for the region.

  6. Air-water gas exchange of chlorinated pesticides in four lakes spanning a 1,205 meter elevation range in the Canadian Rocky Mountains.

    Science.gov (United States)

    Wilkinson, Andrew C; Kimpe, Lynda E; Blais, Jules M

    2005-01-01

    Concentrations of selected persistent organic pollutants (POPs) in air and water were measured from four lakes that transect the Canadian Rocky Mountains. These data were used in combination with wind velocity and temperature-adjusted Henry's law constants to estimate the direction and magnitude of chemical exchange across the air-water interface of these lakes. Bow Lake (1,975 m above sea level [masl]) was studied during the summers of 1998 through 2000; Donald (770 masl) was studied during the summer of 1999; Dixon Dam Lake (946 masl) and Kananaskis Lake (1,667 masl) were studied during the summer of 2000. Hexachlorobenzene (HCB) and dieldrin volatilized from Bow Lake in spring and summer of 1998 to 2000 at a rate of 0.92 +/-1.1 and 0.55+/-0.37 ng m(-2) d(-1), respectively. The alpha-endosulfan deposited to Bow Lake at a rate of 3.4+/-2.2 ng m(-2) d(-1). Direction of gas exchange for gamma-hexachlorocyclohexane (gamma-HCH) changed from net deposition in 1998 to net volatilization in 1999, partly because of a surge in y-HCH concentrations in the water at Bow Lake in 1999. Average gamma-HCH concentrations in air declined steadily over the three-year period, from 0.021 ng m(-3) in 1998, to 0.0023 ng m(-3) in 2000, and to volatilization in 1999 and 2000. Neither the concentrations of organochlorine compounds (OCs) in air and water, nor the direction and rate of air-water gas exchange correlate with temperature or elevation. In general, losses of pesticides by outflow were greater than the amount exchanged across the air-water interface in these lakes.

  7. Tropical Glaciers

    Science.gov (United States)

    Fountain, Andrew

    The term "tropical glacier" calls to mind balmy nights and palm trees on one hand and cold, blue ice on the other. Certainly author Gabriel Garcia Marqez exploited this contrast in One Hundred Years of Solitude. We know that tropical fish live in warm, Sun-kissed waters and tropical plants provide lush, dense foliage populated by colorful tropical birds. So how do tropical glaciers fit into this scene? Like glaciers everywhere, tropical glaciers form where mass accumulation—usually winter snow—exceeds mass loss, which is generally summer melt. Thus, tropical glaciers exist at high elevations where precipitation can occur as snowfall exceeds melt and sublimation losses, such as the Rwenzori Mountains in east Africa and the Maoke Range of Irian Jaya.

  8. Rocky road in the Rockies: Challenges to biodiversity

    Science.gov (United States)

    Tomback, Diana F.; Kendall, Katherine C.; Baron, Jill S.

    2002-01-01

    degree of natural ecosystem processes and preserve natural biodiversity in light of these challenges, Americans and Canadians are faced with the need for intensive, hands-on management of both ecosystems and selected plant and animal populations. In this chapter, we first discuss the primary issues regarding the biodiversity of the Rocky Mountains, including the Rocky Mountain portions of Arizona, Colorado, Idaho, Montana, New Mexico, Utah, Wyoming, British Columbia, and Alberta. Next, we survey groups of organisms to examine their status and special problems. Finally, we touch on major challenges to biodiversity that loom in the near future. Given that entire books may be written on these issues, the discussion is brief and general, but with case histories for more detailed examples.

  9. Arctic polynya and glacier interactions

    Science.gov (United States)

    Edwards, Laura

    2013-04-01

    Major uncertainties surround future estimates of sea level rise attributable to mass loss from the polar ice sheets and ice caps. Understanding changes across the Arctic is vital as major potential contributors to sea level, the Greenland Ice Sheet and the ice caps and glaciers of the Canadian Arctic archipelago, have experienced dramatic changes in recent times. Most ice mass loss is currently focused at a relatively small number of glacier catchments where ice acceleration, thinning and calving occurs at ocean margins. Research suggests that these tidewater glaciers accelerate and iceberg calving rates increase when warming ocean currents increase melt on the underside of floating glacier ice and when adjacent sea ice is removed causing a reduction in 'buttressing' back stress. Thus localised changes in ocean temperatures and in sea ice (extent and thickness) adjacent to major glacial catchments can impact hugely on the dynamics of, and hence mass lost from, terrestrial ice sheets and ice caps. Polynyas are areas of open water within sea ice which remain unfrozen for much of the year. They vary significantly in size (~3 km2 to > ~50,000 km2 in the Arctic), recurrence rates and duration. Despite their relatively small size, polynyas play a vital role in the heat balance of the polar oceans and strongly impact regional oceanography. Where polynyas develop adjacent to tidewater glaciers their influence on ocean circulation and water temperatures may play a major part in controlling subsurface ice melt rates by impacting on the water masses reaching the calving front. Areas of open water also play a significant role in controlling the potential of the atmosphere to carry moisture, as well as allowing heat exchange between the atmosphere and ocean, and so can influence accumulation on (and hence thickness of) glaciers and ice caps. Polynya presence and size also has implications for sea ice extent and therefore potentially the buttressing effect on neighbouring

  10. Rocky Mountain Spotted Fever

    Science.gov (United States)

    ... with facebook share with twitter share with linkedin Rocky Mountain Spotted Fever Credit: CDC A male cayenne tick, Amblyomma cajennense, ... and New Mexico. Why Is the Study of Rocky Mountain Spotted Fever a Priority for NIAID? Tickborne diseases are becoming ...

  11. Rocky Mountain spotted fever

    Science.gov (United States)

    ... spotted fever on the foot Rocky Mountain spotted fever, petechial rash Antibodies Deer and dog tick References McElligott SC, Kihiczak GG, Schwartz RA. Rocky Mountain spotted fever and other rickettsial infections. In: Lebwohl MG, Heymann ...

  12. Very small glaciers under climate change: from the local to the global scale

    Science.gov (United States)

    Huss, M.; Fischer, M.

    2015-12-01

    Very small glaciers (climate archive. Very small glaciers have generally shorter response times than valley glaciers and their mass balance is strongly dependent on snow redistribution processes. Worldwide glacier monitoring has focused on medium-sized to large glaciers leaving us with a relatively limited understanding of the behavior of very small glaciers. With warming climate there is an increasing concern that very small glaciers might be the first to disappear. Already in the next decades this might result in the complete deglaciation of mountain ranges with glacier equilibrium lines close to the highest peaks, such as in the Rocky Mountains, the European Alps, the Andes or parts of High Mountain Asia. In this contribution, we present a comprehensive modelling framework to assess past and future changes in very small glaciers at the mountain-range scale. Among other processes our model accounts for snow redistribution, changes in glacier geometry and dynamic changes in debris-coverage, and computes e.g. distributed mass balance, englacial temperature and proglacial runoff. Detailed glacier projections until 2060 are shown for the Swiss Alps based on new data sets, and the 21st century contribution of all very small glaciers worldwide to sea-level rise is quantified using a global model. Grid-based modelling of surface mass balance and retreat for 1133 very small glaciers in Switzerland indicates that 70% of them will completely vanish within the next 25 years. However, a few avalanche-fed glaciers at low elevation might be able to survive even substantial atmospheric warming. We find relatively high static and dynamic sensitivities for gently-sloping glaciers. At the global scale, glaciers presently smaller than 1 km2 make up for only 0.7% of total ice volume but account for 6.7% of sea-level rise contribution during the period 2015-2025. This indicates that very small glaciers are a non-negligible component of global glacier change, at least in the near

  13. Glaciers of North America - Glaciers of Alaska

    Science.gov (United States)

    Molnia, Bruce F.

    2008-01-01

    Glaciers cover about 75,000 km2 of Alaska, about 5 percent of the State. The glaciers are situated on 11 mountain ranges, 1 large island, an island chain, and 1 archipelago and range in elevation from more than 6,000 m to below sea level. Alaska's glaciers extend geographically from the far southeast at lat 55 deg 19'N., long 130 deg 05'W., about 100 kilometers east of Ketchikan, to the far southwest at Kiska Island at lat 52 deg 05'N., long 177 deg 35'E., in the Aleutian Islands, and as far north as lat 69 deg 20'N., long 143 deg 45'W., in the Brooks Range. During the 'Little Ice Age', Alaska's glaciers expanded significantly. The total area and volume of glaciers in Alaska continue to decrease, as they have been doing since the 18th century. Of the 153 1:250,000-scale topographic maps that cover the State of Alaska, 63 sheets show glaciers. Although the number of extant glaciers has never been systematically counted and is thus unknown, the total probably is greater than 100,000. Only about 600 glaciers (about 1 percent) have been officially named by the U.S. Board on Geographic Names (BGN). There are about 60 active and former tidewater glaciers in Alaska. Within the glacierized mountain ranges of southeastern Alaska and western Canada, 205 glaciers (75 percent in Alaska) have a history of surging. In the same region, at least 53 present and 7 former large ice-dammed lakes have produced jokulhlaups (glacier-outburst floods). Ice-capped volcanoes on mainland Alaska and in the Aleutian Islands have a potential for jokulhlaups caused by subglacier volcanic and geothermal activity. Because of the size of the area covered by glaciers and the lack of large-scale maps of the glacierized areas, satellite imagery and other satellite remote-sensing data are the only practical means of monitoring regional changes in the area and volume of Alaska's glaciers in response to short- and long-term changes in the maritime and continental climates of the State. A review of the

  14. Glaciers of Europe

    Science.gov (United States)

    Williams, Richard S.; Ferrigno, Jane G.

    1993-01-01

    ALPS: AUSTRIAN: An overview is provided on the occurrence of the glaciers in the Eastern Alps of Austria and on the climatic conditions in this area, Historical documents on the glaciers have been available since the Middle Ages. Special glaciological observations and topographic surveys of individual glaciers were initiated as early as 1846. Recent data in an inventory based on aerial photographs taken in 1969 show 925 glaciers in the Austrian Alps with a total area of 542 square kilometers. Present research topics include studies of mass and energy balance, relations of glaciers and climate, physical glaciology, a complete inventory of the glaciers, and testing of remote sensing methods. The location of the glacier areas is shown on Landsat multispectral scanner images; the improved capabilities of the Landsat thematic mapper are illustrated with an example from the Oztaler Alpen group. ALPS: SWISS: According to a glacier inventory published in 1976, which is based on aerial photography of 1973, there are 1,828 glacier units in the Swiss Alps that cover a total area of 1fl42 square kilometers. The Rhonegletscher, currently the ninth largest in the country, was one of the first to be studied in detail. Its surface has been surveyed repeatedly; velocity profiles were measured, and the fluctuations of its terminus were mapped and recorded from 1874 to 1914. Recent research on the glacier has included climatological, hydrological, and massbalance studies. Glaciological research has been conducted on various other glaciers in Switzerland concerning glacier hydrology, glacier hazards, fluctuations of glacier termini, ice mechanics, ice cores, and mass balance. Good maps are available showing the extent of glaciers from the latter decades of the 19th century. More recently, the entire country has been mapped at scales of 1:25,000, 1:50,000, 1:100,000, 1:200,000, and 1:500,000. The 1:25,000-scale series very accurately represents the glaciers as well as locates

  15. Glacier Photograph Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Glacier Photograph Collection is a database of photographs of glaciers from around the world, some dating back to the mid-1850's, that provide an historical...

  16. World Glacier Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The World Glacier Inventory (WGI) contains information for over 130,000 glaciers. Inventory parameters include geographic location, area, length, orientation,...

  17. Glaciers between two drivers

    DEFF Research Database (Denmark)

    Machguth, Horst

    2014-01-01

    It is assumed that the monsoon is the dominant influence on Himalayan glaciers. However, a study now investigates the importance of the mid-latitude Westerlies and shows that glacier changes can be triggered from afar.......It is assumed that the monsoon is the dominant influence on Himalayan glaciers. However, a study now investigates the importance of the mid-latitude Westerlies and shows that glacier changes can be triggered from afar....

  18. Glaciers of Asia

    Science.gov (United States)

    Williams, Richard S.; Ferrigno, Jane G.

    2010-01-01

    This chapter is the ninth to be released in U.S. Geological Survey Professional Paper 1386, Satellite Image Atlas of Glaciers of the World, a series of 11 chapters. In each of the geographic area chapters, remotely sensed images, primarily from the Landsat 1, 2, and 3 series of spacecraft, are used to analyze the specific glacierized region of our planet under consideration and to monitor glacier changes. Landsat images, acquired primarily during the middle to late 1970s and early 1980s, were used by an international team of glaciologists and other scientists to study various geographic regions and (or) to discuss related glaciological topics. In each glacierized geographic region, the present areal distribution of glaciers is compared, wherever possible, with historical information about their past extent. The atlas provides an accurate regional inventory of the areal extent of glacier ice on our planet during the 1970s as part of a growing international scientific effort to measure global environmental change on the Earth?s surface. The chapter is divided into seven geographic parts and one topical part: Glaciers of the Former Soviet Union (F-1), Glaciers of China (F-2), Glaciers of Afghanistan (F?3), Glaciers of Pakistan (F-4), Glaciers of India (F-5), Glaciers of Nepal (F?6), Glaciers of Bhutan (F-7), and the Paleoenvironmental Record Preserved in Middle-Latitude, High-Mountain Glaciers (F-8). Each geographic section describes the glacier extent during the 1970s and 1980s, the benchmark time period (1972-1981) of this volume, but has been updated to include more recent information. Glaciers of the Former Soviet Union are located in the Russian Arctic and various mountain ranges of Russia and the Republics of Georgia, Kyrgyzstan, Tajikistan, and Kazakstun. The Glacier Inventory of the USSR and the World Atlas of Ice and Snow Resources recorded a total of 28,881 glaciers covering an area of 78,938 square kilometers (km2). China includes many of the mountain-glacier

  19. Biogeographic, cultural, and historical setting of the Northern Rocky Mountains [Chapter 2

    Science.gov (United States)

    S. Karen. Dante-Wood

    2018-01-01

    The Northern Rockies Adaptation Partnership (NRAP) includes diverse landscapes, ranging from high mountains to grasslands, from alpine glaciers to broad rivers (fig. 1.1). This region, once inhabited solely by Native Americans, has been altered by two centuries of settlement by Euro- Americans through extractive practices such as timber harvest, grazing, and mining,...

  20. Updated Estimates of Glacier Mass Change for Western North America

    Science.gov (United States)

    Menounos, B.; Gardner, A. S.; Howat, I.; Berthier, E.; Dehecq, A.; Noh, M. J.; Pelto, B. M.

    2017-12-01

    Alpine glaciers are critical components in Western North America's hydrologic cycle. We use varied remotely-sensed datasets to provide updated mass change estimates for Region 2 of the Randolf Glacier Inventory (RGI-02 - all North American glaciers outside of Alaska). Our datasets include: i) aerial laser altimetry surveys completed over many thousands of square kilometers; and ii) multiple Terabytes of high resolution optical stereo imagery (World View 1-3 and Pleiades). Our data from the period 2014-2017 includes the majority of glaciers in RGI-02, specifically those ice masses in the Rocky Mountains (US and Canada), Interior Ranges in British Columbia and the Cascade Mountains (Washington). We co-registered and bias corrected the recent surface models to the Shuttle Radar Topographic Mapping (SRTM) data acquired in February, 2000. In British Columbia, our estimates of mass change are within the uncertainty estimates obtained for the period 1985-2000, but estimates from some regions indicate accelerated mass loss. Work is also underway to update glacier mass change estimates for glaciers in Washington and Montana. Finally, we use re-analysis data (ERA interim and ERA5) to evaluate the meteorological drivers that explain the temporal and spatial variability of mass change evident in our analysis.

  1. Rocky Flats Compliance Program

    International Nuclear Information System (INIS)

    1994-02-01

    The Department of Energy (DOE) established the Office of Technology Development (EM-50) (OTD) as an element of Environmental Restoration and Waste Management (EM) in November 1989. The primary objective of the Office of Technology Development, Rocky Flats Compliance Program (RFCP), is to develop altemative treatment technologies for mixed low-level waste (wastes containing both hazardous and radioactive components) to use in bringing the Rocky Flats Plant (RFP) into compliance with Federal and state regulations and agreements. Approximately 48,000 cubic feet of untreated low-level mixed waste, for which treatment has not been specified, are stored at the RFP. The cleanup of the Rocky Flats site is driven by agreements between DOE, the Environmental Protection Agency (EPA), and the Colorado Department of Health (CDH). Under these agreements, a Comprehensive Treatment and Management Plan (CTMP) was drafted to outline the mechanisms by which RFP will achieve compliance with the regulations and agreements. This document describes DOE's strategy to treat low-level mixed waste to meet Land Disposal Restrictions and sets specific milestones related to the regulatory aspects of technology development. These milestones detail schedules for the development of technologies to treat all of the mixed wastes at the RFP. Under the Federal Facilities Compliance Act (FFCA), the CTMP has been incorporated into Rocky Flats Plant Conceptual Site Treatment Plan (CSTP). The CSTP will become the Rocky Flats Plant site Treatment Plan in 1995 and will supersede the CTMP

  2. Updating the results of glacier contribution to the sea level change

    Science.gov (United States)

    Dyurgerov, Mark B.; Abdalati, Waleed Dr. (Technical Monitor)

    2005-01-01

    I have completed an update of global glacier volume change. All data of glacier annual mass balances, surface area over the period 1945/46 till 2004, outside the Greenland and Antarctic ice sheets were included in this update. As the result global glacier volume change have been calculated, also in terms of glacier contribution to sea level change. These results were sent to Working Group 1 and 2 of IPCC-4 as the basis for modeling of sea level towards the end of 2100. In this study I have concentrated on studying glacier systems of different scales, from primary (e.g. Devon ice cap) to regional (e.g. Canadian Arctic), continental scale (e,g., entire Arctic), and global (e.g., change in glacier volume and contribution to sea level rise).

  3. Glaciers and society

    DEFF Research Database (Denmark)

    Gagné, Karine; Rasmussen, Mattias Borg; Orlove, Ben

    2014-01-01

    As icons of a world set in motion by human action, glaciers are often highlighted as quintessential evidences of global climate change. Although there is a general agreement among scientists that glaciers around the world are receding, much of the discussions on the subject tend to be oriented...... true when esthetic and economic values are assigned to glaciers. Real and perceived changes in the form, reach and out-flow of water impact the local populations, and shape the kinds of action undertaken by communities, local actors, state authorities, and international organizations. The paper...

  4. Climate-induced glacier and snow loss imperils alpine stream insects

    Science.gov (United States)

    Giersch, J. Joseph; Hotaling, Scott; Kovach, Ryan; Jones, Leslie A.; Muhlfeld, Clint C.

    2017-01-01

    Climate warming is causing rapid loss of glaciers and snowpack in mountainous regions worldwide. These changes are predicted to negatively impact the habitats of many range-restricted species, particularly endemic, mountaintop species dependent on the unique thermal and hydrologic conditions found only in glacier-fed and snowmelt-driven alpine streams. Though progress has been made, existing understanding of the status, distribution, and ecology of alpine aquatic species, particularly in North America, is lacking, thereby hindering conservation and management programs. Two aquatic insects – the meltwater stonefly Lednia tumana and the glacier stonefly Zapada glacier – were recently proposed for listing under the U.S. Endangered Species Act due to climate-change-induced habitat loss. Using a large dataset (272 streams, 482 total sites) with high-resolution climate and habitat information, we describe the distribution, status, and key environmental features that limit L. tumana and Z. glacier across the northern Rocky Mountains. Lednia tumana was detected in 113 streams (175 sites) within Glacier National Park (GNP) and surrounding areas. The probability of L. tumana occurrence increased with cold stream temperatures and close proximity to glaciers and permanent snowfields. Similarly, densities of L. tumana declined with increasing distance from stream source. Zapada glacier was only detected in 10 streams (20 sites), six in GNP and four in mountain ranges up to ~600 km southwest. Our results show that both L. tumana and Z. glacier inhabit an extremely narrow distribution, restricted to short sections of cold, alpine streams often below glaciers predicted to disappear over the next two decades. Climate warming-induced glacier and snow loss clearly imperils the persistence of L. tumana and Z. glacier throughout their ranges, highlighting the role of mountaintop aquatic invertebrates as sentinels of climate change in mid-latitude regions.

  5. Rocky Mountain Riparian Digest

    Science.gov (United States)

    Deborah M. Finch

    2008-01-01

    The Rocky Mountain Riparian Digest presents the many facets of riparian research at the station. Included are articles about protecting the riparian habitat, the social and economic values of riparian environments, watershed restoration, remote sensing tools, and getting kids interested in the science.

  6. The potential for retreating alpine glaciers to alter alpine ecosystems in the Colorado Front Range

    Science.gov (United States)

    Hall, E.; Baron, J.

    2013-12-01

    Glaciers are retreating at an unprecedented rate. In mid-latitude alpine ecosystems the presence of glaciers and rock glaciers govern rates and ecology of alpine and sub-alpine ecosystems. Changes in the thermal environment due to the loss of isothermal habitat and inputs from glacier melt chemistry are altering alpine ecosystems in unpredictable ways. In particular, glacier may be a source of nitrogen that is altering alpine ecosystem dynamics. Loch Vale Watershed (LVWS) located within Rocky Mountain National Park. LVWS contains a surface glacier (Andrew's glacier) and a rock glacier (Taylor's glacier) at the headwater of each of the two drainages within the watershed. We collected precipitation from a National Atmospheric Deposition Site and surface water from multiple alpine lakes and streams during a particularly high and low snow year in the Colorado Front Range. We also sampled stream and lake sediments at each site to analyze the associated microbial community. Concentrations of nitrate and ammonium, relative abundance of amoA (the gene responsible for a key step in the microbial nitrification pathway), and the dual isotope signal to nitrate all point to snow melt as a key deliverer of nitrogen to ecosystems along the Colorado Front Range. However, late summer surface water chemistry is isotopically similar to the chemistry of glacial ice. This suggests that retreating glacier may be an additional source of N to alpine ecosystems and have the potential to alter microbial community composition, biogeochemical rate processes, and ecosystem function. These dynamics are most likely not unique to the Colorado Front Range and should be globally distributed as glaciers continue to retreat in high altitude ecosystems around the world.

  7. The GLIMS Glacier Database

    Science.gov (United States)

    Raup, B. H.; Khalsa, S. S.; Armstrong, R.

    2007-12-01

    The Global Land Ice Measurements from Space (GLIMS) project has built a geospatial and temporal database of glacier data, composed of glacier outlines and various scalar attributes. These data are being derived primarily from satellite imagery, such as from ASTER and Landsat. Each "snapshot" of a glacier is from a specific time, and the database is designed to store multiple snapshots representative of different times. We have implemented two web-based interfaces to the database; one enables exploration of the data via interactive maps (web map server), while the other allows searches based on text-field constraints. The web map server is an Open Geospatial Consortium (OGC) compliant Web Map Server (WMS) and Web Feature Server (WFS). This means that other web sites can display glacier layers from our site over the Internet, or retrieve glacier features in vector format. All components of the system are implemented using Open Source software: Linux, PostgreSQL, PostGIS (geospatial extensions to the database), MapServer (WMS and WFS), and several supporting components such as Proj.4 (a geographic projection library) and PHP. These tools are robust and provide a flexible and powerful framework for web mapping applications. As a service to the GLIMS community, the database contains metadata on all ASTER imagery acquired over glacierized terrain. Reduced-resolution of the images (browse imagery) can be viewed either as a layer in the MapServer application, or overlaid on the virtual globe within Google Earth. The interactive map application allows the user to constrain by time what data appear on the map. For example, ASTER or glacier outlines from 2002 only, or from Autumn in any year, can be displayed. The system allows users to download their selected glacier data in a choice of formats. The results of a query based on spatial selection (using a mouse) or text-field constraints can be downloaded in any of these formats: ESRI shapefiles, KML (Google Earth), Map

  8. Associations between accelerated glacier mass wastage and increased summer temperature in coastal regions

    Science.gov (United States)

    Dyurgerov, M.; McCabe, G.J.

    2006-01-01

    Low-elevation glaciers in coastal regions of Alaska, the Canadian Arctic, individual ice caps around the Greenland ice sheet, and the Patagonia Ice Fields have an aggregate glacier area of about 332 ?? 103 km 2 and account for approximately 42% of all the glacier area outside the Greenland and Antarctic ice sheets. They have shown volume loss, especially since the end of the 1980s, increasing from about 45% in the 1960s to nearly 67% in 2003 of the total wastage from all glaciers on Earth outside those two largest ice sheets. Thus, a disproportionally large contribution of coastal glacier ablation to sea level rise is evident. We examine cumulative standardized departures (1961-2000 reference period) of glacier mass balances and air temperature data in these four coastal regions. Analyses indicate a strong association between increases in glacier volume losses and summer air temperature at regional and global scales. Increases in glacier volume losses in the coastal regions also coincide with an accelerated rate of ice discharge from outlet glaciers draining the Greenland and West Antarctic ice sheets. These processes imply further increases in sea level rise. ?? 2006 Regents of the University of Colorado.

  9. Landscape transformation under the Gåsbreen glacier recession since 1899, southwestern Spitsbergen

    Directory of Open Access Journals (Sweden)

    Ziaja Wiesław

    2016-06-01

    Full Text Available Landscape changes of the Gåsbreen glacier and its vicinity since 1899 are described. Maps at 1:50 000 scale of changes of the glacier’s elevation and extent for the periods 1938–1961, 1961–1990, 1990–2010, and 1938–2010 are analyzed in comparison with results of the authors’ field work in the summer seasons 1983, 1984, 2000, 2005 and 2008. During all the 20th century, the progressive recession of the glacier revealed in a dramatic decrease in the thickness of its lower part, with a small reduction of its area and length. However, further shrinkage produced significant shortening and reduction in area which resulted in final decline of the Goësvatnet glacial dammed lake in 2002. Hence, the lowest (and very thick, up to 150–160 m part of the former glacier tongue and dammed lake were transformed into a new terraced river valley south of the glacier and a typical marginal zone with glacial landforms north of the glacier. Since 1961, the equilibrium line altitude of the Gåsbreen glacier has risen from ca 350 to ca 500 m a.s.l. and now is located below the very steep rocky walls of the Mehesten mountain ridge, 1378 m a.s.l. Hence, the glacier is being fed by snow avalanches from these rocky walls and much more snow melts during the warmer summer seasons, stimulating a quicker recession of the lowest part of the glacier. This recession may be stopped only by significant climate cooling or increase in snow.

  10. Modeling the Rock Glacier Cycle

    Science.gov (United States)

    Anderson, R. S.; Anderson, L. S.

    2016-12-01

    Rock glaciers are common in many mountain ranges in which the ELA lies above the peaks. They represent some of the most identifiable components of today's cryosphere in these settings. Their oversteepened snouts pose often-overlooked hazards to travel in alpine terrain. Rock glaciers are supported by avalanches and by rockfall from steep headwalls. The winter's avalanche cone must be sufficiently thick not to melt entirely in the summer. The spatial distribution of rock glaciers reflects this dependence on avalanche sources; they are most common on lee sides of ridges where wind-blown snow augments the avalanche source. In the absence of rockfall, this would support a short, cirque glacier. Depending on the relationship between rockfall and avalanche patterns, "talus-derived" and "glacier-derived" rock glaciers are possible. Talus-derived: If the spatial distribution of rock delivery is similar to the avalanche pattern, the rock-ice mixture will travel an englacial path that is downward through the short accumulation zone before turning upward in the ablation zone. Advected debris is then delivered to the base of a growing surface debris layer that reduces the ice melt rate. The physics is identical to the debris-covered glacier case. Glacier-derived: If on the other hand rockfall from the headwall rolls beyond the avalanche cone, it is added directly to the ablation zone of the glacier. The avalanche accumulation zone then supports a pure ice core to the rock glacier. We have developed numerical models designed to capture the full range of glacier to debris-covered glacier to rock glacier behavior. The hundreds of meter lengths, tens of meters thicknesses, and meter per year speeds of rock glaciers are well described by the models. The model can capture both "talus-derived" and "glacier-derived" rock glaciers. We explore the dependence of glacier behavior on climate histories. As climate warms, a pure ice debris-covered glacier can transform to a much shorter rock

  11. Kepler's first rocky planet

    DEFF Research Database (Denmark)

    Batalha, N.M.; Borucki, W.J.; Bryson, S.T.

    2011-01-01

    NASA's Kepler Mission uses transit photometry to determine the frequency of Earth-size planets in or near the habitable zone of Sun-like stars. The mission reached a milestone toward meeting that goal: the discovery of its first rocky planet, Kepler-10b. Two distinct sets of transit events were...... tests on the photometric and pixel flux time series established the viability of the planet candidates triggering ground-based follow-up observations. Forty precision Doppler measurements were used to confirm that the short-period transit event is due to a planetary companion. The parent star is bright...

  12. Glaciation of alpine valleys: The glacier - debris-covered glacier - rock glacier continuum

    Science.gov (United States)

    Anderson, Robert S.; Anderson, Leif S.; Armstrong, William H.; Rossi, Matthew W.; Crump, Sarah E.

    2018-06-01

    Alpine ice varies from pure ice glaciers to partially debris-covered glaciers to rock glaciers, as defined by the degree of debris cover. In many low- to mid-latitude mountain ranges, the few bare ice glaciers that do exist in the present climate are small and are found where snow is focused by avalanches and where direct exposure to radiation is minimized. Instead, valley heads are more likely to be populated by rock glaciers, which can number in the hundreds. These rock-cloaked glaciers represent some of the most identifiable components of the cryosphere today in low- to mid-latitude settings, and the over-steepened snouts pose an often overlooked hazard to travel in alpine terrain. Geomorphically, rock glaciers serve as conveyor belts atop which rock is pulled away from the base of cliffs. In this work, we show how rock glaciers can be treated as an end-member case that is captured in numerical models of glaciers that include ice dynamics, debris dynamics, and the feedbacks between them. Specifically, we focus on the transition from debris-covered glaciers, where the modern equilibrium line altitude (ELA) intersects the topography, to rock glaciers, where the modern ELA lies above the topography. On debris-covered glaciers (i.e., glaciers with a partial rock mantle), rock delivered to the glacier from its headwall, or from sidewall debris swept into the glacier at tributary junctions, travels englacially to emerge below the ELA. There it accumulates on the surface and damps the rate of melt of underlying ice. This allows the termini of debris-covered glaciers to extend beyond debris-free counterparts, thereby decreasing the ratio of accumulation area to total area of the glacier (AAR). In contrast, rock glaciers (i.e., glaciers with a full rock mantle) occur where and when the environmental ELA rises above the topography. They require avalanches and rockfall from steep headwalls. The occurrence of rock glaciers reflects this dependence on avalanche sources

  13. GLACIERS OF THE KORYAK VOLCANO

    Directory of Open Access Journals (Sweden)

    T. M. Manevich

    2012-01-01

    Full Text Available The paper presents main glaciological characteristics of present-day glaciers located on the Koryaksky volcano. The results of fieldwork (2008–2009 and high-resolution satellite image analysis let us to specify and complete information on modern glacial complex of Koryaksky volcano. Now there are seven glaciers with total area 8.36 km2. Three of them advance, two are in stationary state and one degrades. Moreover, the paper describes the new crater glacier.

  14. Numerical Modeling of Rocky Mountain Paleoglaciers - Insights into the Climate of the Last Glacial Maximum and the Subsequent Deglaciation

    Science.gov (United States)

    Leonard, E. M.; Laabs, B. J. C.; Plummer, M. A.

    2014-12-01

    Numerical modeling of paleoglaciers can yield information on the climatic conditions necessary to sustain those glaciers. In this study we apply a coupled 2-d mass/energy balance and flow model (Plummer and Phillips, 2003) to reconstruct local last glacial maximum (LLGM) glaciers and paleoclimate in ten study areas along the crest of the U.S. Rocky Mountains between 33°N and 49°N. In some of the areas, where timing of post-LLGM ice recession is constrained by surface exposure ages on either polished bedrock upvalley from the LLGM moraines or post-LLGM recessional moraines, we use the model to assess magnitudes and rates of climate change during deglaciation. The modeling reveals a complex pattern of LLGM climate. The magnitude of LLGM-to-modern climate change (temperature and/or precipitation change) was greater in both the northern (Montana) Rocky Mountains and southern (New Mexico) Rocky Mountains than in the middle (Wyoming and Colorado) Rocky Mountains. We use temperature depression estimates from global and regional climate models to infer LLGM precipitation from our glacier model results. Our results suggest a reduction of precipitation coupled with strongly depressed temperatures in the north, contrasted with strongly enhanced precipitation and much more modest temperature depression in the south. The middle Rocky Mountains of Colorado and Wyoming appear to have experienced a reduction in precipitation at the LLGM without the strong temperature depression of the northern Rocky Mountains. Preliminary work on modeling of deglaciation in the Sangre de Cristo Range in southern Colorado suggests that approximately half of the LLGM-to-modern climate change took place during the initial ~2400 years of deglaciation. If increasing temperature and changing solar insolation were the sole drivers of this initial deglaciation, then temperature would need to have risen by slightly more than 1°C/ky through this interval to account for the observed rate of ice recession.

  15. The Open Global Glacier Model

    Science.gov (United States)

    Marzeion, B.; Maussion, F.

    2017-12-01

    Mountain glaciers are one of the few remaining sub-systems of the global climate system for which no globally applicable, open source, community-driven model exists. Notable examples from the ice sheet community include the Parallel Ice Sheet Model or Elmer/Ice. While the atmospheric modeling community has a long tradition of sharing models (e.g. the Weather Research and Forecasting model) or comparing them (e.g. the Coupled Model Intercomparison Project or CMIP), recent initiatives originating from the glaciological community show a new willingness to better coordinate global research efforts following the CMIP example (e.g. the Glacier Model Intercomparison Project or the Glacier Ice Thickness Estimation Working Group). In the recent past, great advances have been made in the global availability of data and methods relevant for glacier modeling, spanning glacier outlines, automatized glacier centerline identification, bed rock inversion methods, and global topographic data sets. Taken together, these advances now allow the ice dynamics of glaciers to be modeled on a global scale, provided that adequate modeling platforms are available. Here, we present the Open Global Glacier Model (OGGM), developed to provide a global scale, modular, and open source numerical model framework for consistently simulating past and future global scale glacier change. Global not only in the sense of leading to meaningful results for all glaciers combined, but also for any small ensemble of glaciers, e.g. at the headwater catchment scale. Modular to allow combinations of different approaches to the representation of ice flow and surface mass balance, enabling a new kind of model intercomparison. Open source so that the code can be read and used by anyone and so that new modules can be added and discussed by the community, following the principles of open governance. Consistent in order to provide uncertainty measures at all realizable scales.

  16. Listening to Glaciers: Passive hydroacoustics near marine-terminating glaciers

    Science.gov (United States)

    Pettit, E.C.; Nystuen, J.A.; O'Neel, Shad

    2012-01-01

    The catastrophic breakup of the Larsen B Ice Shelf in the Weddell Sea in 2002 paints a vivid portrait of the effects of glacier-climate interactions. This event, along with other unexpected episodes of rapid mass loss from marine-terminating glaciers (i.e., tidewater glaciers, outlet glaciers, ice streams, ice shelves) sparked intensified study of the boundaries where marine-terminating glaciers interact with the ocean. These dynamic and dangerous boundaries require creative methods of observation and measurement. Toward this effort, we take advantage of the exceptional sound-propagating properties of seawater to record and interpret sounds generated at these glacial ice-ocean boundaries from distances safe for instrument deployment and operation.

  17. Preliminary bathymetry of Northwestern Fiord and Neoglacial changes of Northwestern Glacier

    Science.gov (United States)

    Post, Austin

    1980-01-01

    The first preliminary bathymetry (at 1:20,000 scale) and other scientific investigations of Northwestern Fiord, Alaska, were conducted by the Research Vessel Growler in 1978, disclosing this 10.5-mile-long branched waterway to be a deep basin enclosed by a terminal-moraine shoal. The basin was formerly filled by Northwestern Glacier, which began a drastic retreat around 1909 and reached the head of the main arm around 1960. Soundings and profiles show the main channel to be as much as 970 feet deep and to have the typical U shape of a severely glacially eroded valley; since the glacier 's retreat, sediments have formed nearly level deposits in the deepest reaches, while the rest of the basin has a hard, rocky bottom. Preneoglacial forest debris dated by carbon-14 indicates Northwestern Glacier to have advanced into the fiord prior to 1,385 years before present (B.P.); a branch glacier evidently advanced into forest 1,635 years B.P. The combined glaciers from several arms culminated on the present terminal-moraine shoal around 1894. (USGS)

  18. Soil decontamination at Rocky Flats

    International Nuclear Information System (INIS)

    Olsen, R.L.; Hayden, J.A.; Alford, C.E.; Kochen, R.L.; Stevens, J.R.

    1979-01-01

    A soils decontamination project was initiated, to remove actinides from soils at Rocky Flats. Wet screening, attrition scrubbing with Calgon at high pH, attrition scrubbing at low pH, and cationic flotation were investigated. Pilot plant studies were carried out. Conceptual designs have been generated for mounting the process in semi-trailers

  19. Rocky Mountain spotted fever, Panama.

    Science.gov (United States)

    Estripeaut, Dora; Aramburú, María Gabriela; Sáez-Llorens, Xavier; Thompson, Herbert A; Dasch, Gregory A; Paddock, Christopher D; Zaki, Sherif; Eremeeva, Marina E

    2007-11-01

    We describe a fatal pediatric case of Rocky Mountain spotted fever in Panama, the first, to our knowledge, since the 1950s. Diagnosis was established by immunohistochemistry, PCR, and isolation of Rickettsia rickettsii from postmortem tissues. Molecular typing demonstrated strong relatedness of the isolate to strains of R. rickettsii from Central and South America.

  20. Rocky Mountain spotted fever, Colombia.

    Science.gov (United States)

    Hidalgo, Marylin; Orejuela, Leonora; Fuya, Patricia; Carrillo, Pilar; Hernandez, Jorge; Parra, Edgar; Keng, Colette; Small, Melissa; Olano, Juan P; Bouyer, Donald; Castaneda, Elizabeth; Walker, David; Valbuena, Gustavo

    2007-07-01

    We investigated 2 fatal cases of Rocky Mountain spotted fever that occurred in 2003 and 2004 near the same locality in Colombia where the disease was first reported in the 1930s. A retrospective serosurvey of febrile patients showed that > 21% of the serum samples had antibodies aaainst spotted fever group rickettsiae.

  1. Climate along the crest of the US Rocky Mountains during the last glaciation: preliminary insights from numerical modeling of paleoglaciers

    Science.gov (United States)

    Leonard, E. M.; Laabs, B. J.; Plummer, M. A.; Huss, E.; Spiess, V. M.; Mackall, B. T.; Jacobsen, R. E.; Quirk, B.

    2012-12-01

    Climate conditions at the time of the local Last Glacial Maximum (LGM) in the US Rocky Mountains were assessed using a 2-d coupled glacier energy/mass-balance and ice-flow model (Plummer and Phillips, 2003). The model was employed to understand the conditions that would be necessary to sustain valley glaciers and small mountain icecaps at their maximum extents in eight areas distributed along the crest of the range from northern New Mexico (35.8oN) to northern Montana (48.6oN). For each setting, model experiments yield a set of temperature and precipitation combinations that may have accompanied the local LGM. If the results of global and regional climate models are used to constrain temperature depression estimates from our model experiments, the following precipitation pattern emerges for the local LGM. In the northern Rocky Mountains in Montana and northern Wyoming, model results suggest a strong reduction in precipitation of 50% or more. In the central Rocky Mountains of southern Wyoming and Colorado, precipitation appears to have been 50-90% of modern. By contrast, precipitation appears to have been strongly enhanced in the southern Rocky Mountains of New Mexico. These results are broadly consistent with a pattern of precipitation observed in global and regional climate simulations of the LGM in the western U.S., in which precipitation was reduced in the northern Rocky Mountains but increased in the southern Rocky Mountains. This pattern may reflect a southward displacement of mean position the Pacific Jet Stream in western North America during and possibly following the LGM.

  2. From Glaciers to Icebergs

    Science.gov (United States)

    Zhang, Wendy

    I will describe works from a collaboration between physics and glaciology that grew out of interactions at the Computations in Science seminar Leo Kadanoff organized at the University of Chicago. The first project considers the interaction between ocean waves and Antarctic ice shelves, large floating portions of ice formed by glacial outflows. Back-of-envelop calculation and seismic sensor data suggest that crevasses may be distributed within an ice shelf to shield it from wave energy. We also examine numerical scenarios in which changes in environmental forcing causes the ice shelf to fail catastrophically. The second project investigates the aftermath of iceberg calving off glacier terminus in Greenland using data recorded via time-lapse camera and terrestrial radar. Our observations indicate that the mélange of icebergs within the fjord experiences widespread jamming during a calving event and therefore is always close to being in a jammed state during periods of terminus quiescence. Joint work with Jason Amundson, Ivo R. Peters, Julian Freed Brown, Nicholas Guttenberg, Justin C Burton, L. Mac Cathles, Ryan Cassotto, Mark Fahnestock, Kristopher Darnell, Martin Truffer, Dorian S. Abbot and Douglas MacAyeal. Kadanoff Session DCMP.

  3. Airborne Surface Profiling of Alaskan Glaciers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of glacier outline, laser altimetry profile, and surface elevation change data for 46 glaciers in Alaska and British Columbia, Canada,...

  4. Rock glaciers, Central Andes, Argentina, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — Primary rock glaciers are fed by avalanche chutes. At the El Salto rock glacier, surveys have been undertaken in order to determine the creep rate. Between 1981 and...

  5. Erosion by pleistocene continental ice sheets in the area of the Canadian Shield

    International Nuclear Information System (INIS)

    Rutter, N.W.

    The principles, theory and knowledge on the behaviour of glaciers indicate that only confined glacier flow is a major erosional agent. Unconfined, areally flowing ice sheets such as those present over the Canadian Shield during the Pleistocene Period modified the landscape very little. The potential for deep glacial erosion in future glaciations over the Canadian Shield area is low. Nuclear waste disposal sites, based only upon potential glacial erosion, should be located a few hundred meters below the surface in competent, fractureless crystalline shield bedrock, in relatively reliefless terrain, a few hundred kilometers away from the Paleozoic boundary. (auth)

  6. Managing Rocky Mountain spotted fever.

    Science.gov (United States)

    Minniear, Timothy D; Buckingham, Steven C

    2009-11-01

    Rocky Mountain spotted fever is caused by the tick-borne bacterium Rickettsia rickettsii. Symptoms range from moderate illness to severe illness, including cardiovascular compromise, coma and death. The disease is prevalent in most of the USA, especially during warmer months. The trademark presentation is fever and rash with a history of tick bite, although tick exposure is unappreciated in over a third of cases. Other signature symptoms include headache and abdominal pain. The antibiotic therapy of choice for R. rickettsii infection is doxycycline. Preventive measures for Rocky Mountain spotted fever and other tick-borne diseases include: wearing long-sleeved, light colored clothing; checking for tick attachment and removing attached ticks promptly; applying topical insect repellent; and treating clothing with permethrin.

  7. Residue management at Rocky Flats

    International Nuclear Information System (INIS)

    Olencz, J.

    1995-01-01

    Past plutonium production and manufacturing operations conducted at the Rocky Flats Environmental Technology Site (RFETS) produced a variety of plutonium-contaminated by-product materials. Residues are a category of these materials and were categorized as open-quotes materials in-processclose quotes to be recovered due to their inherent plutonium concentrations. In 1989 all RFETS plutonium production and manufacturing operations were curtailed. This report describes the management of plutonium bearing liquid and solid wastes

  8. Towards a unified estimate of arctic glaciers contribution to sea level rise since 1972.

    Science.gov (United States)

    Dehecq, A.; Gardner, A. S.; Alexandrov, O.; McMichael, S.

    2017-12-01

    Glaciers retreat contributed to about 1/3 of the observed sea level rise since 1971 (IPCC). However, long term estimates of glaciers volume changes rely on sparse field observations and region-wide satellite observations are available mostly after 2000. The recently declassified images from the reconnaissance satellite series Hexagon (KH9), that acquired 6 m resolution stereoscopic images from 1971 to 1986, open new possibilities for glaciers observation. But the film-printed images represent a processing challenge. Here we present an automatic workflow developed to generate Digital Elevation Models (DEMs) at 24 m resolution from the raw scanned KH9 images. It includes a preprocessing step to detect fiducial marks and to correct distortions of the film caused by the 40-year storage. An estimate of the unknown satellite position is obtained from a crude geolocation of the images. Each stereo image pair/triplet is then processed using the NASA Ames Stereo Pipeline to derive an unscaled DEM using standard photogrammetric techniques. This DEM is finally aligned to a reference topography, to account for errors in translation, rotation and scaling. In a second part, we present DEMs generated over glaciers in the Canadian Arctic and analyze glaciers volume changes from 1970 to the more recent WorldView ArcticDEM.

  9. Mass budget of Queen Elizabeth Islands glaciers and ice caps, Canada, from 1992 to present

    Science.gov (United States)

    Millan, R.; Rignot, E. J.; Mouginot, J.

    2015-12-01

    Recent studies indicate to say that the Canadian Artic Archipelago's mass loss has increased in recent years. However the role of ice dynamics changes in this area is not well known. In this study, we present a comprehensive velocity mapping of the CAA using ALOS/PALSAR, RADARSAT-1, ERS1 and Landsat data between 1992 and 2015. Glaciers speed are calculated using a speckle and feature tracking algorithm.The results reveals that three large marine-terminating glaciers have accelerated significantly after 2010, while most others have slowed down or retreated to a sill to become similar to land-terminating glaciers. By combining the velocities of these glaciers with ice thickness measurements from NASA's Operation IceBridge, we calculate their ice discharge. The fluxes of these glaciers increased significantly since 2000 with a marked increase after 2011. The comparison of ice discharge with the surface mass balance from RACMO-2, shows that these glaciers came out of balance after 2011, which is also a time period where their discharge almost doubled. The analysis of RACMO-2 reveals an increase in runoff between 1970's and today and a precipitation with no significant trend. We digitalize the calving front positions of the glaciers and show an increasing rate retreat since 1976. We conclude that global pattern of velocity changes shows that the mass losses due to surface mass balance will likely going to raise in the coming years and that ice discharge will have a smaller part in the contribution of the CAA to sea level rise.

  10. The impact of expanding Canadian gas imports in the U.S. Midwest

    International Nuclear Information System (INIS)

    Parker, S.

    2000-01-01

    The new competitive natural gas market in the U. S. Midwest is surveyed from an interstate pipeline point of view, taking into account Canadian gas imports, increase in Rocky Mountain imports competing with Canadian imports, the flow dynamics in the Midwest market, supply basin production trends, the infrastructure improvements in local distribution companies, improvements in storage facilities, and the growing demand for natural gas-fired generation

  11. Rocky Mountain Research Station: 2011 Annual Accomplishments

    Science.gov (United States)

    Rick Fletcher

    2011-01-01

    The Rocky Mountain Research Station is one of seven regional units that make up the USDA Forest Service Research and Development organization ­ the most extensive natural resources research organization in the world. We maintain 12 field laboratories throughout a 12-state territory encompassing the Great Basin, Southwest, Rocky Mountains, and parts of the Great Plains...

  12. Rocky Mountain Research Station: 2010 Research Accomplishments

    Science.gov (United States)

    Rick Fletcher

    2010-01-01

    The Rocky Mountain Research Station is one of seven regional units that make up the USDA Forest Service Research and Development organization ­ the most extensive natural resources research organization in the world. We maintain 12 field laboratories throughout a 12-state territory encompassing the Great Basin, Southwest, Rocky Mountains, and parts of the Great Plains...

  13. Rocky Mountain spotted fever in children.

    Science.gov (United States)

    Woods, Charles R

    2013-04-01

    Rocky Mountain spotted fever is typically undifferentiated from many other infections in the first few days of illness. Treatment should not be delayed pending confirmation of infection when Rocky Mountain spotted fever is suspected. Doxycycline is the drug of choice even for infants and children less than 8 years old. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Rocky Mountain Spotted Fever: Statistics and Epidemiology

    Science.gov (United States)

    ... Search Form Controls Cancel Submit Search the CDC Rocky Mountain Spotted Fever (RMSF) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Rocky Mountain Spotted Fever (RMSF) Transmission Signs and Symptoms Diagnosis and Testing ...

  15. Radiation monitor training program at Rocky Flats

    International Nuclear Information System (INIS)

    Medina, L.C.; Kittinger, W.D.; Vogel, R.M.

    The Rocky Flats Radiation Monitor Training Program is tailored to train new health physics personnel in the field of radiation monitoring. The purpose of the prescribed materials and media is to be consistent in training in all areas of Rocky Flats radiation monitoring job involvement

  16. The Glacier National Park: A popular guide to its geology and scenery

    Science.gov (United States)

    Campbell, Marius R.

    1914-01-01

    The Glacier National Park includes that part of the Front Range of the Rocky Mountains lying just south of the Canadian line, in Teton and Flathead counties, Mont. It is bounded on the west by Flathead River (locally called North Fork), on the south by the Middle Fork of Flathead River and the Great Northern Railway, and on the east by the Blackfeet Indian Reservation. Although this part of the Rocky Mountains has been known since Lewis and Clark crossed the continent in 1805-6, the region later made a park appears not to have been visited by white men until 1853, when Cut Bank Pass was crossed by A. W. Tinkham, one of the Government engineers engaged in exploring a route for the Pacific railroad. Tinkham, who was encamped in the Bitterroot Valley, was ordered to examine Marias Pass, but in traversing Middle Fork of Flathead River along the line of the present railroad he was evidently misled by the large size of the valley of Nyack Creek and ascended that instead of keeping to the right up the main stream. He reported the pass impracticable for railroad construction, and so this region dropped out of public attention for a long time. The next explorers to enter the region were a group of surveyors who, under the direction of American and British commissioners, established the international boundary line along the forty-ninth parallel from the Pacific coast to the main summit of the Rocky Mountains. This party reached the area now included in the park in the summer of 1861, and the stone monument shown in Plate I, B, which they erected on the Continental Divide west of Waterton Lake, still marks a point on the boundary between the United States and Canada. The land on the west side of the range formed a part of the public domain which, until the erection of the park, was open to settlement, but the land on the east originally belonged to the Blackfeet Indians and the white men had no rights upon it. About 1890 copper ore was found near the heads of Quartz and

  17. Glacier area changes in Northern Eurasia

    International Nuclear Information System (INIS)

    Khromova, Tatiana; Nosenko, Gennady; Kutuzov, Stanislav; Muraviev, Anton; Chernova, Ludmila

    2014-01-01

    Glaciers are widely recognized as key indicators of climate change. Recent evidence suggests an acceleration of glacier mass loss in several key mountain regions. Glacier recession implies landscape changes in the glacial zone, the origin of new lakes and activation of natural disaster processes, catastrophic mudflows, ice avalanches, outburst floods, etc. The absence or inadequacy of such information results in financial and human losses. A more comprehensive evaluation of glacier changes is imperative to assess ice contributions to global sea level rise and the future of water resources from glacial basins. One of the urgent steps is a full inventory of all ice bodies and their changes. The first estimation of glacier state and glacier distribution on the territory of the former Soviet Union has been done in the USSR Glacier Inventory (UGI) published in 1965–1982. The UGI is based on topographic maps and air photos and reflects the status of the glaciers in the 1940s–1970s. There is information about 28 884 glaciers with an area of 7830.75 km 2 in the inventory. It covers 25 glacier systems in Northern Eurasia. In the 1980s the UGI has been transformed into digital form as a part of the World Glacier Inventory (WGI). Recent satellite data provide a unique opportunity to look again at these glaciers and to evaluate changes in glacier extent for the second part of the 20th century. About 15 000 glacier outlines for the Caucasus, Polar Urals, Pamir Alay, Tien Shan, Altai, Kamchatka and Russian Arctic have been derived from ASTER and Landsat imagery and can be used for glacier change evaluation. Results of the analysis indicate the steady trend in glacier shrinkage in all mountain regions for the second part of the 20th century. Glacier area loss for the studied regions varies from 13% (Tien Shan) to 22.3% (Polar Urals). The common driver, most likely, is an increase in summer air temperature. There is also a very large variability in the degree of

  18. Closing Rocky Flats by 2006

    International Nuclear Information System (INIS)

    Tuor, N. R.; Schubert, A. L.

    2002-01-01

    Safely accelerating the closure of Rocky Flats to 2006 is a goal shared by many: the State of Colorado, the communities surrounding the site, the U.S. Congress, the Department of Energy, Kaiser-Hill and its team of subcontractors, the site's employees, and taxpayers across the country. On June 30, 2000, Kaiser-Hill (KH) submitted to the Department of Energy (DOE), KH's plan to achieve closure of Rocky Flats by December 15, 2006, for a remaining cost of $3.96 billion (February 1, 2000, to December 15, 2006). The Closure Project Baseline (CPB) is the detailed project plan for accomplishing this ambitious closure goal. This paper will provide a status report on the progress being made toward the closure goal. This paper will: provide a summary of the closure contract completion criteria; give the current cost and schedule variance of the project and the status of key activities; detail important accomplishments of the past year; and discuss the challenges ahead

  19. Assessment of lake sensitivity to acidic deposition in national parks of the Rocky Mountains

    Science.gov (United States)

    Nanus, L.; Williams, M.W.; Campbell, D.H.; Tonnessen, K.A.; Blett, T.; Clow, D.W.

    2009-01-01

    The sensitivity of high-elevation lakes to acidic deposition was evaluated in five national parks of the Rocky Mountains based on statistical relations between lake acid-neutralizing capacity concentrations and basin characteristics. Acid-neutralizing capacity (ANC) of 151 lakes sampled during synoptic surveys and basin-characteristic information derived from geographic information system (GIS) data sets were used to calibrate the statistical models. The explanatory basin variables that were considered included topographic parameters, bedrock type, and vegetation type. A logistic regression model was developed, and modeling results were cross-validated through lake sampling during fall 2004 at 58 lakes. The model was applied to lake basins greater than 1 ha in area in Glacier National Park (n = 244 lakes), Grand Teton National Park (n = 106 lakes), Great Sand Dunes National Park and Preserve (n = 11 lakes), Rocky Mountain National Park (n = 114 lakes), and Yellowstone National Park (n = 294 lakes). Lakes that had a high probability of having an ANC concentration 3000 m, with 80% of the catchment bedrock having low buffering capacity. The modeling results indicate that the most sensitive lakes are located in Rocky Mountain National Park and Grand Teton National Park. This technique for evaluating the lake sensitivity to acidic deposition is useful for designing long-term monitoring plans and is potentially transferable to other remote mountain areas of the United States and the world.

  20. Classification of debris-covered glaciers and rock glaciers in the Andes of central Chile

    Science.gov (United States)

    Janke, Jason R.; Bellisario, Antonio C.; Ferrando, Francisco A.

    2015-07-01

    In the Dry Andes of Chile (17 to 35° S), debris-covered glaciers and rock glaciers are differentiated from true glaciers based on the percentage of surface debris cover, thickness of surface debris, and ice content. Internal ice is preserved by an insulating cover of thick debris, which acts as a storage reservoir to release water during the summer and early fall. These landforms are more numerous than glaciers in the central Andes; however, the existing legislation only recognizes uncovered or semicovered glaciers as a water resource. Glaciers, debris-covered glaciers, and rock glaciers are being altered or removed by mining operations to extract valuable minerals from the mountains. In addition, agricultural expansion and population growth in this region have placed additional demands on water resources. In a warmer climate, as glaciers recede and seasonal water availability becomes condensed over the course of a snowmelt season, rock glaciers and debris-covered glaciers contribute a larger component of base flow to rivers and streams. As a result, identifying and locating these features to implement sustainable regional planning for water resources is important. The objective of this study is to develop a classification system to identify debris-covered glaciers and rock glaciers based on the interpretation of satellite imagery and aerial photographs. The classification system is linked to field observations and measurements of ice content. Debris-covered glaciers have three subclasses: surface coverage of semi (class 1) and fully covered (class 2) glaciers differentiates the first two forms, whereas debris thickness is critical for class 3 when glaciers become buried with more than 3 m of surface debris. Based on field observations, the amount of ice decreases from more than 85%, to 65-85%, to 45-65% for semi, fully, and buried debris-covered glaciers, respectively. Rock glaciers are characterized by three stages. Class 4 rock glaciers have pronounced

  1. Long-range Rocky Flats utilization study

    International Nuclear Information System (INIS)

    1983-02-01

    The purpose of this Study was to provide information concerning the Rocky Flats Plant and its operations that will be useful to the Nation's decision-makers in determining the long-range future of the Plant. This Study was conducted under the premise that national defense policy must be supported and, accordingly, the capabilities at Rocky Flats must be maintained there or at some other location(s). The Study, therefore, makes no attempt to speculate on how possible future changes in national defense policy might affect decisions regarding the utilization of Rocky Flats. Factors pertinent to decisions regarding Rocky Flats, which are included in the Study, are: physical condition of the Plant and its vulnerabilities to natural phenomena; risks associated with plutonium to Plant workers and the public posed by postulated natural phenomena and operational accidents; identification of alternative actions regarding the future use of the Rocky Flats Plant with associated costs and time scales; local socioeconomic impacts if Rocky Flats operations were relocated; and potential for other uses if Rocky Flats facilities were vacated. The results of the tasks performed in support of this Study are summarized in the context of these five factors

  2. Fault Dating in the US Rockies and Large Regional Extent of Deformation Pulses Along the Sevier Orogen of North America.

    Science.gov (United States)

    van der Pluijm, B.; Lynch, E. A.; Pana, D.; Yonkee, A.

    2017-12-01

    Recent Ar dating of clay-rich fault rock in the Canadian Rockies identified multiple orogenic pulses: Late Jurassic (163-146 Ma), Mid-Cretaceous (103-99 Ma), Late Cretaceous (76-72 Ma) and Eocene (54-52 Ma; Pana and van der Pluijm, GSAB 2015). New dating in the US Rockies combined with ages in the most frontal section along an Idaho-Wyoming transect show a remarkably similar age pattern: Meade Thrust, 108-102 Ma; (S)Absaroka Thrust, 73 Ma; Darby-Bear Thrust, 56-50 Ma. These radiometric fault ages in the US Rockies match field and tectono-stratigraphic predictions, analogues to those in the Canadian Rockies. Thus, a remarkably long (>1500km) lateral tract along the North American Sevier orogen is characterized by at least three major orogenic pulses that are structurally contiguous. These orogenic pulses are progressively younger in the direction of easterly thrust fault motion (toward cratonic interior) and are separated by long periods of relative tectonic quiescence. We interpret the extensive regional continuity of deformation pulses and tectonic quiescence along the Sevier Orogen as the result of three plate reorganization events in western North America since the Late Jurassic.

  3. Sediment transport drives tidewater glacier periodicity.

    Science.gov (United States)

    Brinkerhoff, Douglas; Truffer, Martin; Aschwanden, Andy

    2017-07-21

    Most of Earth's glaciers are retreating, but some tidewater glaciers are advancing despite increasing temperatures and contrary to their neighbors. This can be explained by the coupling of ice and sediment dynamics: a shoal forms at the glacier terminus, reducing ice discharge and causing advance towards an unstable configuration followed by abrupt retreat, in a process known as the tidewater glacier cycle. Here we use a numerical model calibrated with observations to show that interactions between ice flow, glacial erosion, and sediment transport drive these cycles, which occur independent of climate variations. Water availability controls cycle period and amplitude, and enhanced melt from future warming could trigger advance even in glaciers that are steady or retreating, complicating interpretations of glacier response to climate change. The resulting shifts in sediment and meltwater delivery from changes in glacier configuration may impact interpretations of marine sediments, fjord geochemistry, and marine ecosystems.The reason some of the Earth's tidewater glaciers are advancing despite increasing temperatures is not entirely clear. Here, using a numerical model that simulates both ice and sediment dynamics, the authors show that internal dynamics drive glacier variability independent of climate.

  4. A database of worldwide glacier thickness observations

    DEFF Research Database (Denmark)

    Gärtner-Roer, I.; Naegeli, K.; Huss, M.

    2014-01-01

    One of the grand challenges in glacier research is to assess the total ice volume and its global distribution. Over the past few decades the compilation of a world glacier inventory has been well-advanced both in institutional set-up and in spatial coverage. The inventory is restricted to glacier...... the different estimation approaches. This initial database of glacier and ice caps thickness will hopefully be further enlarged and intensively used for a better understanding of the global glacier ice volume and its distribution....... surface observations. However, although thickness has been observed on many glaciers and ice caps around the globe, it has not yet been published in the shape of a readily available database. Here, we present a standardized database of glacier thickness observations compiled by an extensive literature...... review and from airborne data extracted from NASA's Operation IceBridge. This database contains ice thickness observations from roughly 1100 glaciers and ice caps including 550 glacier-wide estimates and 750,000 point observations. A comparison of these observational ice thicknesses with results from...

  5. Internationally coordinated glacier monitoring: strategy and datasets

    Science.gov (United States)

    Hoelzle, Martin; Armstrong, Richard; Fetterer, Florence; Gärtner-Roer, Isabelle; Haeberli, Wilfried; Kääb, Andreas; Kargel, Jeff; Nussbaumer, Samuel; Paul, Frank; Raup, Bruce; Zemp, Michael

    2014-05-01

    Internationally coordinated monitoring of long-term glacier changes provide key indicator data about global climate change and began in the year 1894 as an internationally coordinated effort to establish standardized observations. Today, world-wide monitoring of glaciers and ice caps is embedded within the Global Climate Observing System (GCOS) in support of the United Nations Framework Convention on Climate Change (UNFCCC) as an important Essential Climate Variable (ECV). The Global Terrestrial Network for Glaciers (GTN-G) was established in 1999 with the task of coordinating measurements and to ensure the continuous development and adaptation of the international strategies to the long-term needs of users in science and policy. The basic monitoring principles must be relevant, feasible, comprehensive and understandable to a wider scientific community as well as to policy makers and the general public. Data access has to be free and unrestricted, the quality of the standardized and calibrated data must be high and a combination of detailed process studies at selected field sites with global coverage by satellite remote sensing is envisaged. Recently a GTN-G Steering Committee was established to guide and advise the operational bodies responsible for the international glacier monitoring, which are the World Glacier Monitoring Service (WGMS), the US National Snow and Ice Data Center (NSIDC), and the Global Land Ice Measurements from Space (GLIMS) initiative. Several online databases containing a wealth of diverse data types having different levels of detail and global coverage provide fast access to continuously updated information on glacier fluctuation and inventory data. For world-wide inventories, data are now available through (a) the World Glacier Inventory containing tabular information of about 130,000 glaciers covering an area of around 240,000 km2, (b) the GLIMS-database containing digital outlines of around 118,000 glaciers with different time stamps and

  6. Brief communication: Getting Greenland's glaciers right - a new data set of all official Greenlandic glacier names

    Science.gov (United States)

    Bjørk, A. A.; Kruse, L. M.; Michaelsen, P. B.

    2015-12-01

    Place names in Greenland can be difficult to get right, as they are a mix of Greenlandic, Danish, and other foreign languages. In addition, orthographies have changed over time. With this new data set, we give the researcher working with Greenlandic glaciers the proper tool to find the correct name for glaciers and ice caps in Greenland and to locate glaciers described in the historic literature with the old Greenlandic orthography. The data set contains information on the names of 733 glaciers, 285 originating from the Greenland Ice Sheet (GrIS) and 448 from local glaciers and ice caps (LGICs).

  7. How do glacier inventory data aid global glacier assessments and projections?

    Science.gov (United States)

    Hock, R.

    2017-12-01

    Large-scale glacier modeling relies heavily on datasets that are collected by many individuals across the globe, but managed and maintained in a coordinated fashion by international data centers. The Global Terrestrial Network for Glaciers (GTN-G) provides the framework for coordinating and making available a suite of data sets such as the Randolph Glacier Inventory (RGI), the Glacier Thickness Dataset or the World Glacier Inventory (WGI). These datasets have greatly increased our ability to assess global-scale glacier mass changes. These data have also been vital for projecting the glacier mass changes of all mountain glaciers in the world outside the Greenland and Antarctic ice sheet, a total >200,000 glaciers covering an area of more than 700,000 km2. Using forcing from 8 to 15 GCMs and 4 different emission scenarios, global-scale glacier evolution models project multi-model mean net mass losses of all glaciers between 7 cm and 24 cm sea-level equivalent by the end of the 21st century. Projected mass losses vary greatly depending on the choice of the forcing climate and emission scenario. Insufficiently constrained model parameters likely are an important reason for large differences found among these studies even when forced by the same emission scenario, especially on regional scales.

  8. Using Metaphorical Models for Describing Glaciers

    Science.gov (United States)

    Felzmann, Dirk

    2014-01-01

    To date, there has only been little conceptual change research regarding conceptions about glaciers. This study used the theoretical background of embodied cognition to reconstruct different metaphorical concepts with respect to the structure of a glacier. Applying the Model of Educational Reconstruction, the conceptions of students and scientists…

  9. The atmospheric boundary layer over melting glaciers

    NARCIS (Netherlands)

    Oerlemans, J.

    1998-01-01

    Results from a number of glacio-meteorological experiments carried out over melting glaciers are summarized. It is shown that in summer the microclimate of a glacier tongue is dominated by katabatic flow, initiated by the downward sensible heat flux. Characteristic obstacle height is an

  10. The response of glaciers to climate change

    NARCIS (Netherlands)

    Klok, Elisabeth Jantina

    2003-01-01

    The research described in this thesis addresses two aspects of the response of glaciers to climate change. The first aspect deals with the physical processes that govern the interaction between glaciers and climate change and was treated by (1) studying the spatial and temporal variation of the

  11. Glaciers in 21st Century Himalayan Geopolitics

    Science.gov (United States)

    Kargel, J. S.; Wessels, R.; Kieffer, H. H.

    2002-05-01

    Glaciers are ablating rapidly the world over. Nowhere are the rates of retreat and downwasting greater than in the Hindu Kush-Himalaya (HKH) region. It is estimated that over the next century, 40,000 square kilometers of present glacier area in the HKH region will become ice free. Most of this area is in major valleys and the lowest glaciated mountain passes. The existence and characteristics of glaciers have security impacts, and rapidly changing HKH glaciers have broad strategic implications: (1) Glaciers supply much of the fresh water and hydroelectric power in South and Central Asia, and so glaciers are valuable resources. (2) Shared economic interests in water, hydroelectricity, flood hazards, and habitat preservation are a force for common cause and reasoned international relations. (3) Glaciers and their high mountains generally pose a natural barrier tending to isolate people. Historically, they have hindered trade and intercultural exchanges and have protected against aggression. This has further promoted an independent spirit of the region's many ethnic groups. (4) Although glaciers are generally incompatible with human development and habitation, many of the HKH region's glaciers and their mountains have become sanctuaries and transit routes for militants. Siachen Glacier in Kashmir has for 17 years been "the world's highest battlefield," with tens of thousands of troops deployed on both sides of the India/Pakistan line of control. In 1999, that conflict threatened to trigger all-out warfare, and perhaps nuclear warfare. Other recent terrorist and military action has taken place on glaciers in Kyrgyzstan and Tajikistan. As terrorists are forced from easily controlled territories, many may tend to migrate toward the highest ground, where definitive encounters may take place in severe alpine glacial environments. This should be a major concern in Nepali security planning, where an Army offensive is attempting to reign in an increasingly robust and brutal

  12. An inventory and estimate of water stored in firn fields, glaciers, debris-covered glaciers, and rock glaciers in the Aconcagua River Basin, Chile

    Science.gov (United States)

    Janke, Jason R.; Ng, Sam; Bellisario, Antonio

    2017-11-01

    An inventory of firn fields, glaciers, debris-covered glaciers, and rock glaciers was conducted in the Aconcagua River Basin of the semiarid Andes of central Chile. A total of 916 landforms were identified, of which rock glaciers were the most abundant (669) and occupied the most total area. Glaciers and debris-covered glaciers were less numerous, but were about five times larger in comparison. The total area occupied by glaciers and debris-covered glaciers was roughly equivalent to the total area of rock glaciers. Debris-covered glaciers and rock glaciers were subcategorized into six ice-content classes based on interpretation of surface morphology with high-resolution satellite imagery. Over 50% of rock glaciers fell within a transitional stage; 85% of debris-covered glaciers were either fully covered or buried. Most landforms occupied elevations between 3500 and 4500 m. Glaciers and firn occurred at higher elevations compared to rock glaciers and debris-covered glaciers. Rock glaciers had a greater frequency in the northern part of the study area where arid climate conditions exist. Firn and glaciers were oriented south, debris-covered glaciers west, and rock glaciers southwest. An analysis of water contribution of each landform in the upper Andes of the Aconcagua River Basin was conducted using formulas that associate the size of the landforms to estimates of water stored. Minimum and maximum water storage was calculated based on a range of debris to ice content ratios for debris-covered glaciers and rock glaciers. In the Aconcagua River Basin, rock glaciers accounted for 48 to 64% of the water stored within the landforms analyzed; glaciers accounted for 15 to 25%; debris-covered glaciers were estimated at 15 to 19%; firn fields contained only about 5 to 8% of the water stored. Expansion of agriculture, prolonged drought, and removal of ice-rich landforms for mining have put additional pressure on already scarce water resources. To develop long

  13. The "Canadian" in Canadian Children's Literature.

    Science.gov (United States)

    Bainbridge, Joyce; Wolodko, Brenda

    2001-01-01

    Notes that a rich body of Canadian children's literature exists that reflects the country's literary and socio-cultural values, beliefs, themes and images, including those of geography, history, language and identity. Discusses how Canadians tend to identify themselves first by region or province and then by nation. (SG)

  14. Protest: The Canadian pulse

    International Nuclear Information System (INIS)

    Lott, J.E.

    1979-01-01

    This popularly written article compares Canadian attitudes to protests against nuclear power to those in the United States. Canadian protesters are more peaceful, expressing their opinions within the law. The article describes the main anti-nuclear groups in Canada and presents the results of public opinion surveys of Canadians on the use of nuclear power for generating electricity. (TI)

  15. Response of small glaciers to climate change: runoff from glaciers of the Wind River range, Wyoming

    Science.gov (United States)

    Bliss, A. K.; Stamper, B.

    2017-12-01

    Runoff from glaciers affects downstream ecosystems by influencing the quantity, seasonality, and chemistry of the water. We describe the present state of glaciers in the Wind River range, Wyoming and consider how these glaciers will change in the future. Wind River glaciers have been losing mass in recent decades, as seen with geodetic techniques and by examining glacier morphology. Interestingly, the 2016/7 winter featured one of the largest snowfalls on record. Our primary focus is the Dinwoody Glacier ( 3 km^2, 3300-4000 m above sea level). We present data collected in mid-August 2017 including glacier ablation rates, snow line elevations, and streamflow. We compare measured glacier mass loss to streamflow at the glacier terminus and at a USGS stream gauge farther downstream. Using a hydrological model, we explore the fate of glacial runoff as it moves into downstream ecosystems and through ranchlands important to local people. The techniques used here can be applied to similar small-glacier systems in other parts of the world.

  16. Seasonal variability of organic matter composition in an Alaskan glacier outflow: insights into glacier carbon sources

    International Nuclear Information System (INIS)

    Spencer, Robert G M; Vermilyea, Andrew; Fellman, Jason; Hood, Eran; Raymond, Peter; Stubbins, Aron; Scott, Durelle

    2014-01-01

    Glacier ecosystems are a significant source of bioavailable, yet ancient dissolved organic carbon (DOC). Characterizing DOC in Mendenhall Glacier outflow (southeast Alaska) we document a seasonal persistence to the radiocarbon-depleted signature of DOC, highlighting ancient DOC as a ubiquitous feature of glacier outflow. We observed no systematic depletion in Δ 14 C-DOC with increasing discharge during the melt season that would suggest mobilization of an aged subglacial carbon store. However, DOC concentration, δ 13 C-DOC, Δ 14 C-DOC and fluorescence signatures appear to have been influenced by runoff from vegetated hillslopes above the glacier during onset and senescence of melt. In the peak glacier melt period, the Δ 14 C-DOC of stream samples at the outflow (−181.7 to −355.3‰) was comparable to the Δ 14 C-DOC for snow samples from the accumulation zone (−207.2 to −390.9‰), suggesting that ancient DOC from the glacier surface is exported in glacier runoff. The pre-aged DOC in glacier snow and runoff is consistent with contributions from fossil fuel combustion sources similar to those documented previously in ice cores and thus provides evidence for anthropogenic perturbation of the carbon cycle. Overall, our results emphasize the need to further characterize DOC inputs to glacier ecosystems, particularly in light of predicted changes in glacier mass and runoff in the coming century. (papers)

  17. Ocean impact on Nioghalvfjerdsfjorden Glacier, Northeast Greenland

    Science.gov (United States)

    Schaffer, Janin; Kanzow, Torsten; von Appen, Wilken-Jon; Mayer, Christoph

    2017-04-01

    The ocean plays an important role in modulating the mass balance of the Greenland Ice Sheet by delivering heat to the marine-terminating outlet glaciers around Greenland. The largest of three outlet glaciers draining the Northeast Greenland Ice Stream is Nioghalvfjerdsfjorden Glacier (also referred to as 79 North Glacier). Historic observations showed that warm waters of Atlantic origin are present in the subglacial cavity below the 80 km long floating ice tongue of the Nioghalvfjerdsfjorden Glacier and cause strong basal melt at the grounding line, but to date it has been unknown how those warm water enter the cavity. In order to understand how Atlantic origin waters carry heat into the subglacial cavity beneath Nioghalvfjerdsfjorden Glacier, we performed bathymetric, hydrographic, and velocity observations in the vicinity of the main glacier calving front aboard RV Polarstern in summer 2016. The bathymetric multibeam data shows a 500 m deep and 2 km narrow passage downstream of a 310 m deep sill. This turned out to be the only location deep enough for an exchange of Atlantic waters between the glacier cavity and the continental shelf. Hydrographic and velocity measurements revealed a density driven plume in the vicinity of the glacier calving front causing a rapid flow of waters of Atlantic origin warmer 1°C into the subglacial cavity through the 500 m deep passage. In addition, glacially modified waters flow out of the glacier cavity below the 80 m deep ice base. In the vicinity of the glacier, the glacially modified waters form a distinct mixed layer situated above the Atlantic waters and below the ambient Polar water. At greater distances from the glacier this layer is eroded by lateral mixing with ambient water. Based on our observations we will present an estimate of the ocean heat transport into the subglacial cavity. In comparison with historic observations we find an increase in Atlantic water temperatures throughout the last 20 years. The resulting

  18. Glaciers in Patagonia: Controversy and prospects

    Science.gov (United States)

    Kargel, J. S.; Alho, P.; Buytaert, W.; Célleri, R.; Cogley, J. G.; Dussaillant, A.; Guido, Z.; Haeberli, W.; Harrison, S.; Leonard, G.; Maxwell, A.; Meier, C.; Poveda, G.; Reid, B.; Reynolds, J.; Rodríguez, C. A. Portocarrero; Romero, H.; Schneider, J.

    2012-05-01

    Lately, glaciers have been subjects of unceasing controversy. Current debate about planned hydroelectric facilities—a US7- to 10-billion megaproject—in a pristine glacierized area of Patagonia, Chile [Romero Toledo et al., 2009; Vince, 2010], has raised anew the matter of how glaciologists and global change experts can contribute their knowledge to civic debates on important issues. There has been greater respect for science in this controversy than in some previous debates over projects that pertain to glaciers, although valid economic motivations again could trump science and drive a solution to the energy supply problem before the associated safety and environmental problems are understood. The connection between glaciers and climate change—both anthropogenic and natural—is fundamental to glaciology and to glaciers' practical importance for water and hydropower resources, agriculture, tourism, mining, natural hazards, ecosystem conservation, and sea level [Buytaert et al., 2010; Glasser et al., 2011]. The conflict between conservation and development can be sharper in glacierized regions than almost anywhere else. Glaciers occur in spectacular natural landscapes, but they also supply prodigious exploitable meltwater.

  19. Quantifying seasonal velocity at Khumbu Glacier, Nepal

    Science.gov (United States)

    Miles, E.; Quincey, D. J.; Miles, K.; Hubbard, B. P.; Rowan, A. V.

    2017-12-01

    While the low-gradient debris-covered tongues of many Himalayan glaciers exhibit low surface velocities, quantifying ice flow and its variation through time remains a key challenge for studies aimed at determining the long-term evolution of these glaciers. Recent work has suggested that glaciers in the Everest region of Nepal may show seasonal variability in surface velocity, with ice flow peaking during the summer as monsoon precipitation provides hydrological inputs and thus drives changes in subglacial drainage efficiency. However, satellite and aerial observations of glacier velocity during the monsoon are greatly limited due to cloud cover. Those that do exist do not span the period over which the most dynamic changes occur, and consequently short-term (i.e. daily) changes in flow, as well as the evolution of ice dynamics through the monsoon period, remain poorly understood. In this study, we combine field and remote (satellite image) observations to create a multi-temporal, 3D synthesis of ice deformation rates at Khumbu Glacier, Nepal, focused on the 2017 monsoon period. We first determine net annual and seasonal surface displacements for the whole glacier based on Landsat-8 (OLI) panchromatic data (15m) processed with ImGRAFT. We integrate inclinometer observations from three boreholes drilled by the EverDrill project to determine cumulative deformation at depth, providing a 3D perspective and enabling us to assess the role of basal sliding at each site. We additionally analyze high-frequency on-glacier L1 GNSS data from three sites to characterize variability within surface deformation at sub-seasonal timescales. Finally, each dataset is validated against repeat-dGPS observations at gridded points in the vicinity of the boreholes and GNSS dataloggers. These datasets complement one another to infer thermal regime across the debris-covered ablation area of the glacier, and emphasize the seasonal and spatial variability of ice deformation for glaciers in High

  20. Role of glacier runoff in the Heihe Basin

    OpenAIRE

    坂井, 亜規子; 藤田, 耕史; 中尾, 正義; YAO, Tandong

    2005-01-01

    We estimated the fluctuation of precipitation and air temperature from Dunde ice core data since 1606 comparing to meteorological data taken near the July 1st glacier since 1930s. Then, we calculated the discharges from glaciers and glacier-free areaFurthermore, we analyzed the sensitivity of those discharges to meteorological factor. The result revealed that calculated discharge from glacier-free area increased with precipitation. Meanwhile, calculated discharge from glaciers decreased with ...

  1. Glacier Instability, Rapid Glacier Lake Growth and Related Hazards at Belvedere Glacier, Macugnaga, Italy

    Science.gov (United States)

    Huggel, C.; Kaeaeb, A.; Haeberli, W.; Mortara, G.; Chiarle, M.; Epifani, F.

    2002-12-01

    Starting in summer 2000, Belvedere Glacier, near Macugnaga, Italian Alps, developed an extraordinary change in flow, geometry and surface appearance. A surge-type flow acceleration started in the lower parts of the Monte-Rosa east face, leading to strong crevassing and deformation of Belvedere Glacier, accompanied by bulging of its orographic right margin. In September 2001, a small supraglacial lake developed on the glacier. High water pressure and accelerated movement lasted into winter 2001/2002. The ice, in places, started to override moraines from the Little Ice Age. In late spring and early summer 2002, the supraglacial lake grew at extraordinary rates reaching a maximum area of more than 150'000 m2 by end of June. The evolution of such a large supraglacial lake, a rather unique feature in the Alps, was probably enabled by changes in the subglacial drainage system in the course of the surge-like developments with high water pressure in the glacier. At the end of June, an enhanced growth of the lake level with a rise of about 1 m per day was observed such that the supraglacial lake became a urgent hazard problem for the community of Macugnaga. Emergency measures had to be taken by the Italian Civil Protection. The authors thereby acted as the official expert advisers. Temporal evacuations were ordered and a permanent monitoring and alarm system was installed. Pumps with a maximum output of 1 m3/s were brought to the lake. Bathymetric studies yielded a maximum lake depth of 55 m and a volume of 3.3 millions of cubic meters of water. Aerial photography of 1995, 1999, September 2001 and October 2001 was used to calculate ice flow velocities and changes in surface altitude. Compared to the period of 1995 to 1999, the flow accelerated by about five times in 2001 (max. speeds up to 200 m/yr). Surface uplift measured was about 10-15 m/yr. The results of the photogrammetric studies were used to evaluate different possible lake-outburst scenarios, in particular

  2. Accelerated contributions of Canada's Baffin and Bylot Island glaciers to sea level rise over the past half century

    Directory of Open Access Journals (Sweden)

    A. Gardner

    2012-10-01

    Full Text Available Canadian Arctic glaciers have recently contributed large volumes of meltwater to the world's oceans. To place recently observed glacier wastage into a historical perspective and to determine the region's longer-term (~50 years contribution to sea level, we estimate mass and volume changes for the glaciers of Baffin and Bylot Islands using digital elevation models generated from airborne and satellite stereoscopic imagery and elevation postings from repeat airborne and satellite laser altimetry. In addition, we update existing glacier mass change records from GRACE satellite gravimetry to cover the period from 2003 to 2011. Using this integrated approach, we find that the rate of mass loss from the region's glaciers increased from 11.1 ± 3.4 Gt a−1 (271 ± 84 kg m−2 a−1 for the period 1963–2006 to 23.8 ± 6.1 Gt a−1 (581 ± 149 kg m−2 a−1 for the period 2003–2011. The doubling of the rate of mass loss is attributed to higher temperatures in summer with little change in annual precipitation. Through both direct and indirect effects, changes in summer temperatures accounted for 70–98% of the variance in the rate of mass loss, to which the Barnes Ice Cap was found to be 1.7 times more sensitive than either the Penny Ice Cap or the region's glaciers as a whole. This heightened sensitivity is the result of a glacier hypsometry that is skewed to lower elevations, which are shown to have a higher mass change sensitive to temperature compared to glacier surfaces at higher elevations. Between 2003 and 2011 the glaciers of Baffin and Bylot Islands contributed 0.07 ± 0.02 mm a−1 to sea level rise accounting for 16% of the total contribution from glaciers outside of Greenland and Antarctica, a rate much higher than the longer-term average of 0.03 ± 0.01 mm a−1 (1963 to 2006.

  3. Glacier development and topographic context

    DEFF Research Database (Denmark)

    López-Moreno, J. I.; Nogués-Bravo, David; Chueca-Cía, J.

    2006-01-01

    This paper analyses the topographic context of the remaining glaciated areas in the Maladeta Massif (Central Spanish Pyrenees). These ice-covered surfaces have been incorporated into a geographic information system (GIS) in an attempt at correlating the presence of ice with a range of topographic...... and recent evolution of each glacial body. Thus, the joint effect of altitude, exposure to incoming solar radiation, slope and mean curvature is able to explain more than 70 per cent of the observed variance. Copyright © 2006 John Wiley & Sons, Ltd....... variables obtained from a digital elevation model. The use of generalized additive models and binary regression tree models enabled us (i) to quantify the spatial variability in the distribution of glaciers attributable to characteristics of the local terrain, (ii) to investigate the interaction between...

  4. A case of Rocky Mountain spotted fever.

    Science.gov (United States)

    Rubel, Barry S

    2007-01-01

    Rocky Mountain spotted fever is a serious, generalized infection that is spread to humans through the bite of infected ticks. It can be lethal but it is curable. The disease gets its name from the Rocky Mountain region where it was first identified in 1896. The fever is caused by the bacterium Rickettsia rickettsii and is maintained in nature in a complex life cycle involving ticks and mammals. Humans are considered to be accidental hosts and are not involved in the natural transmission cycle of this pathogen. The author examined a 47-year-old woman during a periodic recall appointment. The patient had no dental problems other than the need for routine prophylaxis but mentioned a recent problem with swelling of her extremities with an accompanying rash and general malaise and soreness in her neck region. Tests were conducted and a diagnosis of Rocky Mountain spotted fever was made.

  5. ROCK GLACIERS IN THE KOLYMA HIGHLAND

    Directory of Open Access Journals (Sweden)

    A. A. Galanin

    2012-01-01

    Full Text Available Based on remote mapping and field studies inGrand Rapids, Tumansky,Hasynsky,Del-Urechen Ridges as well as Dukchinsky and Kilgansky Mountain Massifs there were identified about 1160 landforms which morphologically are similar to the rock glaciers or they develop in close association with them. Besides tongue-shaped cirque rock glaciers originated due to ablation, a large number of lobate-shaped slope-associated rock glaciers were recognized. Significant quantity of such forms are developing within the active neotectonic areas, in zones of seismic-tectonic badland and in association with active earthquakes-controlling faults. Multiplication of regional data on volcanic-ash-chronology, lichenometry, Schmidt Hammer Test, pollen spectra and single radiocarbon data, most of the active rock glaciers were preliminary attributed to the Late Holocene.

  6. Rock glaciers, Prealps, Vaud, Switzerland, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — The investigated area forms part of the western lobe of the Prealps (Swiss Prealps). The 25 identified fossil rock glaciers are found mainly in the Prealpes medianes...

  7. Issues evaluation process at Rocky Flats Plant

    International Nuclear Information System (INIS)

    Smith, L.C.

    1992-01-01

    This report describes the issues evaluation process for Rocky Flats Plant as established in July 1990. The issues evaluation process was initiated February 27, 1990 with a Charter and Process Overview for short-term implementation. The purpose of the process was to determine the projects required for completion before the Phased Resumption of Plutonium Operations. To determine which projects were required, the issues evaluation process and emphasized risk mitigation, based on a ranking system. The purpose of this report is to document the early design of the issues evaluation process to record the methodologies used that continue as the basis for the ongoing Issues Management Program at Rocky Flats Plant

  8. Glacier monitoring and glacier-climate interactions in the tropical Andes: A review

    Science.gov (United States)

    Veettil, Bijeesh Kozhikkodan; Wang, Shanshan; Florêncio de Souza, Sergio; Bremer, Ulisses Franz; Simões, Jefferson Cardia

    2017-08-01

    In this review, we summarized the evolution of glacier monitoring in the tropical Andes during the last few decades, particularly after the development of remote sensing and photogrammetry. Advantages and limitations of glacier mapping, applied so far, in Venezuela, Colombia, Ecuador, Peru and Bolivia are discussed in detail. Glacier parameters such as the equilibrium line altitude, snowline and mass balance were given special attention in understanding the complex cryosphere-climate interactions, particularly using remote sensing techniques. Glaciers in the inner and the outer tropics were considered separately based on the precipitation and temperature conditions within a new framework. The applicability of various methods to use glacier records to understand and reconstruct the tropical Andean climate between the Last Glacial Maximum (11,700 years ago) and the present is also explored in this paper. Results from various studies published recently were analyzed and we tried to understand the differences in the magnitudes of glacier responses towards the climatic perturbations in the inner tropics and the outer tropics. Inner tropical glaciers, particularly those in Venezuela and Colombia near the January Intertropical Convergence Zone (ITCZ), are more vulnerable to increase in temperature. Surface energy balance experiments show that outer tropical glaciers respond to precipitation variability very rapidly in comparison with the temperature variability, particularly when moving towards the subtropics. We also analyzed the gradients in glacier response to climate change from the Pacific coast towards the Amazon Basin as well as with the elevation. Based on the current trends synthesised from recent studies, it is hypothesized that the glaciers in the inner tropics and the southern wet outer tropics will disappear first as a response to global warming whereas glaciers in the northern wet outer tropics and dry outer tropics show resistance to warming trends due to

  9. Fuzzy Cognitive Maps for Glacier Hazards Assessment: Application to Predicting the Potential for Glacier Lake Outbursts

    Science.gov (United States)

    Furfaro, R.; Kargel, J. S.; Fink, W.; Bishop, M. P.

    2010-12-01

    Glaciers and ice sheets are among the largest unstable parts of the solid Earth. Generally, glaciers are devoid of resources (other than water), are dangerous, are unstable and no infrastructure is normally built directly on their surfaces. Areas down valley from large alpine glaciers are also commonly unstable due to landslide potential of moraines, debris flows, snow avalanches, outburst floods from glacier lakes, and other dynamical alpine processes; yet there exists much development and human occupation of some disaster-prone areas. Satellite remote sensing can be extremely effective in providing cost-effective and time- critical information. Space-based imagery can be used to monitor glacier outlines and their lakes, including processes such as iceberg calving and debris accumulation, as well as changing thicknesses and flow speeds. Such images can also be used to make preliminary identifications of specific hazardous spots and allows preliminary assessment of possible modes of future disaster occurrence. Autonomous assessment of glacier conditions and their potential for hazards would present a major advance and permit systematized analysis of more data than humans can assess. This technical leap will require the design and implementation of Artificial Intelligence (AI) algorithms specifically designed to mimic glacier experts’ reasoning. Here, we introduce the theory of Fuzzy Cognitive Maps (FCM) as an AI tool for predicting and assessing natural hazards in alpine glacier environments. FCM techniques are employed to represent expert knowledge of glaciers physical processes. A cognitive model embedded in a fuzzy logic framework is constructed via the synergistic interaction between glaciologists and AI experts. To verify the effectiveness of the proposed AI methodology as applied to predicting hazards in glacier environments, we designed and implemented a FCM that addresses the challenging problem of autonomously assessing the Glacier Lake Outburst Flow

  10. The length of the glaciers in the world

    DEFF Research Database (Denmark)

    Machguth, Horst; Huss, M.; Huss, M.

    2014-01-01

    a fully automated method based on glacier surface slope, distance to the glacier margins and a set of trade-off functions. The method is developed for East Greenland, evaluated for the same area as well as for Alaska, and eventually applied to all ∼ 200000 glaciers around the globe. The evaluation...... highlights accurately calculated glacier length where DEM quality is good (East 10 Greenland) and limited precision on low quality DEMs (parts of Alaska). Measured length of very small glaciers is subject to a certain level of ambiguity. The global calculation shows that only about 1.5% of all glaciers...... are longer than 10km with Bering Glacier (Alaska/Canada) being the longest glacier in the world at a length of 196 km. Based on model output we derive global and regional area-length scaling laws. Differences among regional scaling parameters appear to be related to characteristics of topography and glacier...

  11. Step-wise changes in glacier flow speed coincide with calving and glacial earthquakes at Helheim Glacier, Greenland

    DEFF Research Database (Denmark)

    Nettles, M.; Larsen, T. B.; Elósegui, P.

    2008-01-01

    Geodetic observations show several large, sudden increases in flow speed at Helheim Glacier, one of Greenland's largest outlet glaciers, during summer, 2007. These step-like accelerations, detected along the length of the glacier, coincide with teleseismically detected glacial earthquakes and major...... iceberg calving events. No coseismic offset in the position of the glacier surface is observed; instead, modest tsunamis associated with the glacial earthquakes implicate glacier calving in the seismogenic process. Our results link changes in glacier velocity directly to calving-front behavior...... at Greenland's largest outlet glaciers, on timescales as short as minutes to hours, and clarify the mechanism by which glacial earthquakes occur. Citation: Nettles, M., et al. (2008), Step-wise changes in glacier flow speed coincide with calving and glacial earthquakes at Helheim Glacier, Greenland....

  12. Combination of UAV and terrestrial photogrammetry to assess rapid glacier evolution and map glacier hazards

    Science.gov (United States)

    Fugazza, Davide; Scaioni, Marco; Corti, Manuel; D'Agata, Carlo; Azzoni, Roberto Sergio; Cernuschi, Massimo; Smiraglia, Claudio; Diolaiuti, Guglielmina Adele

    2018-04-01

    Tourists and hikers visiting glaciers all year round face hazards such as sudden terminus collapses, typical of such a dynamically evolving environment. In this study, we analyzed the potential of different survey techniques to analyze hazards of the Forni Glacier, an important geosite located in Stelvio Park (Italian Alps). We carried out surveys in the 2016 ablation season and compared point clouds generated from an unmanned aerial vehicle (UAV) survey, close-range photogrammetry and terrestrial laser scanning (TLS). To investigate the evolution of glacier hazards and evaluate the glacier thinning rate, we also used UAV data collected in 2014 and a digital elevation model (DEM) created from an aerial photogrammetric survey of 2007. We found that the integration between terrestrial and UAV photogrammetry is ideal for mapping hazards related to the glacier collapse, while TLS is affected by occlusions and is logistically complex in glacial terrain. Photogrammetric techniques can therefore replace TLS for glacier studies and UAV-based DEMs hold potential for becoming a standard tool in the investigation of glacier thickness changes. Based on our data sets, an increase in the size of collapses was found over the study period, and the glacier thinning rates went from 4.55 ± 0.24 m a-1 between 2007 and 2014 to 5.20 ± 1.11 m a-1 between 2014 and 2016.

  13. Rocky Mountain spotted fever in dogs, Brazil.

    Science.gov (United States)

    Labruna, Marcelo B; Kamakura, Orson; Moraes-Filho, Jonas; Horta, Mauricio C; Pacheco, Richard C

    2009-03-01

    Clinical illness caused by Rickettsia rickettsii in dogs has been reported solely in the United States. We report 2 natural clinical cases of Rocky Mountain spotted fever in dogs in Brazil. Each case was confirmed by seroconversion and molecular analysis and resolved after doxycycline therapy.

  14. ICESat laser altimetry over small mountain glaciers

    Directory of Open Access Journals (Sweden)

    D. Treichler

    2016-09-01

    Full Text Available Using sparsely glaciated southern Norway as a case study, we assess the potential and limitations of ICESat laser altimetry for analysing regional glacier elevation change in rough mountain terrain. Differences between ICESat GLAS elevations and reference elevation data are plotted over time to derive a glacier surface elevation trend for the ICESat acquisition period 2003–2008. We find spatially varying biases between ICESat and three tested digital elevation models (DEMs: the Norwegian national DEM, SRTM DEM, and a high-resolution lidar DEM. For regional glacier elevation change, the spatial inconsistency of reference DEMs – a result of spatio-temporal merging – has the potential to significantly affect or dilute trends. Elevation uncertainties of all three tested DEMs exceed ICESat elevation uncertainty by an order of magnitude, and are thus limiting the accuracy of the method, rather than ICESat uncertainty. ICESat matches glacier size distribution of the study area well and measures small ice patches not commonly monitored in situ. The sample is large enough for spatial and thematic subsetting. Vertical offsets to ICESat elevations vary for different glaciers in southern Norway due to spatially inconsistent reference DEM age. We introduce a per-glacier correction that removes these spatially varying offsets, and considerably increases trend significance. Only after application of this correction do individual campaigns fit observed in situ glacier mass balance. Our correction also has the potential to improve glacier trend significance for other causes of spatially varying vertical offsets, for instance due to radar penetration into ice and snow for the SRTM DEM or as a consequence of mosaicking and merging that is common for national or global DEMs. After correction of reference elevation bias, we find that ICESat provides a robust and realistic estimate of a moderately negative glacier mass balance of around −0.36 ± 0.07

  15. What Influences Climate and Glacier Change in the Southwestern China?

    Science.gov (United States)

    Yasunari, Teppei J.

    2012-01-01

    The subject of climate change in the areas of the Tibetan Plateau (TP) and the Himalayas has taken on increasing importance because of available water resources from their mountain glaciers. Many of these glaciers over the region have been retreating, while some are advancing and stable. Other studies report that some glaciers in the Himalayas show acceleration on their shrinkage. However, the causes of the glacier meltings are still difficult to grasp because of the complexity of climatic change and its influence on glacier issues. However, it is vital that we pursue further study to enable the future prediction on glacier changes.

  16. Monitoring Unstable Glaciers with Seismic Noise Interferometry

    Science.gov (United States)

    Preiswerk, L. E.; Walter, F.

    2016-12-01

    Gravity-driven glacier instabilities are a threat to human infrastructure in alpine terrain, and this hazard is likely to increase with future changes in climate. Seismometers have been used previously on hazardous glaciers to monitor the natural englacial seismicity. In some situations, an increase in "icequake" activity may indicate fracture growth and thus an imminent major break-off. However, without independent constraints on unstable volumes, such mere event counting is of little use. A promising new approach to monitor unstable masses in Alpine terrain is coda wave interferometry of ambient noise. While already established in the solid earth, application to glaciers is not straightforward, because the lack of inhomogeneities typically suppresses seismic coda waves in glacier ice. Only glaciers with pervasive crevasses provide enough scattering to generate long codas. This is requirement is likely met for highly dynamic unstable glaciers. Here, we report preliminary results from a temporary 5-station on-ice array of seismometers (corner frequencies: 1 Hz, array aperture: 500m) on Bisgletscher (Switzerland). The seismometers were deployed in shallow boreholes, directly above the unstable tongue of the glacier. In the frequency band 4-12 Hz, we find stable noise cross-correlations, which in principle allows monitoring on a subdaily scale. The origin and the source processes of the ambient noise in these frequencies are however uncertain. As a first step, we evaluate the stability of the sources in order to separate effects of changing source parameters from changes of englacial properties. Since icequakes occurring every few seconds may dominate the noise field, we compare their temporal and spatial occurrences with the cross-correlation functions (stability over time, the asymmetry between causal and acausal parts of the cross-correlation functions) as well as with results from beamforming to assess the influence of these transient events on the noise field.

  17. Transport of perfluoroalkyl substances (PFAS) from an arctic glacier to downstream locations: implications for sources.

    Science.gov (United States)

    Kwok, Karen Y; Yamazaki, Eriko; Yamashita, Nobuyoshi; Taniyasu, Sachi; Murphy, Margaret B; Horii, Yuichi; Petrick, Gert; Kallerborn, Roland; Kannan, Kurunthachalam; Murano, Kentaro; Lam, Paul K S

    2013-03-01

    Perfluoroalkyl substances (PFAS) have been globally detected in various environmental matrices, yet their fate and transport to the Arctic is still unclear, especially for the European Arctic. In this study, concentrations of 17 PFAS were quantified in two ice cores (n=26), surface snow (n=9) and surface water samples (n=14) collected along a spatial gradient in Svalbard, Norway. Concentrations of selected ions (Na(+), SO4(2-), etc.) were also determined for tracing the origins and sources of PFAS. Perfluorobutanoate (PFBA), perfluorooctanoate (PFOA) and perfluorononanoate (PFNA) were the dominant compounds found in ice core samples. Taking PFOA, PFNA and perfluorooctane-sulfonate (PFOS) as examples, higher concentrations were detected in the middle layers of the ice cores representing the period of 1997-2000. Lower concentrations of C8-C12 perfluorocarboxylates (PFCAs) were detected in comparison with concentrations measured previously in an ice core from the Canadian Arctic, indicating that contamination levels in the European Arctic are lower. Average PFAS concentrations were found to be lower in surface snow and melted glacier water samples, while increased concentrations were observed in river water downstream near the coastal area. Perfluorohexanesulfonate (PFHxS) was detected in the downstream locations, but not in the glacier, suggesting existence of local sources of this compound. Long-range atmospheric transport of PFAS was the major deposition pathway for the glaciers, while local sources (e.g., skiing activities) were identified in the downstream locations. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Framing Canadian federalism

    National Research Council Canada - National Science Library

    Saywell, John; Anastakis, Dimitry; Bryden, Penny E

    2009-01-01

    ... the pervasive effects that federalism has on Canadian politics, economics, culture, and history, and provide a detailed framework in which to understand contemporary federalism. Written in honour of John T. Saywell's half-century of accomplished and influential scholarly work and teaching, Framing Canadian Federalism is a timely and fitting t...

  19. GlacierRocks - Glacier-Headwall Interaction and its Influence on Rockfall Activity

    Science.gov (United States)

    Hartmeyer, Ingo; Keuschnig, Markus; Krautblatter, Michael; Helfricht, Kay; Leith, Kerry; Otto, Jan-Christoph

    2017-04-01

    Climate models predict continued climate warming and a decrease of Austrian glaciers to less than 20% of their present area by the end of this century. Rockfall from freshly exposed headwalls has been documented as an increasing risk factor with considerable significance for man and high-alpine infrastructure. Recent findings of a five-year terrestrial laserscanning campaign (2011-2016) monitoring glacial headwalls at the Kitzsteinhorn (3.203 m a.s.l.), Hohe Tauern Range, Austria, show the dramatic impact of glacier thinning on adjacent headwalls: 80 % of the detected rockfall volumes were triggered from areas located less than 20 m above the current glacier surface. Despite these implications, little is known about the thermal, mechanical and hydrological processes that operate at the glacier-headwall interface (randkluft). Systemic in-situ monitoring of stability-relevant parameters are lacking, leaving fundamental gaps in the understanding of rockfall preconditioning in glacial headwalls and the geomorphological evolution of glaciated catchments. In this contribution we introduce the recently approved research project 'GlacierRocks', which starts in 2017 and will run for at least three years. 'GlacierRocks' will establish the worldwide first research site for long-term monitoring of stability-relevant processes inside a randkluft system. Based on the acquired monitoring data 'GlacierRocks' is pursuing three overall aims at (1) gaining a better understanding of rockfall preconditioning in randklufts and related geomorphological shaping of headwalls, (2) analyzing poorly understood glacial thinning dynamics near headwalls, and (3) estimating present and future rockfall hazard potential in headwalls on a regional scale. The three system components (headwall, glacier, randkluft) will be investigated by combining geomorphological, glaciological and meteorological methods. 'GlacierRocks' will continuously monitor rock temperature, rock moisture, frost cracking

  20. Updating the New Zealand Glacier Inventory

    Science.gov (United States)

    Baumann, S. C.; Anderson, B.; Mackintosh, A.; Lorrey, A.; Chinn, T.; Collier, C.; Rack, W.; Purdie, H.

    2017-12-01

    The last complete glacier inventory of New Zealand dates from the year 1978 (North Island 1988) and was manually constructed from oblique aerial photographs and geodetic maps (Chinn 2001). The inventory has been partly updated by Gjermundsen et al. (2011) for the year 2002 (40% of total area) and by Sirguey & More (2010) for the year 2009 (32% of total area), both using ASTER satellite imagery. We used Landsat 8 OLI/TIRS satellite data from February/March 2016 to map the total glaciated area. Clean and debris-covered ice were mapped semi-automatically. The band ratio approach was used for clean ice (ratio: red/SWIR). We mapped debris-covered ice using a supervised classification (maximum likelihood). Manual post processing was necessary due to misclassifications (e.g. lakes, clouds) or mapping in shadowed areas. It was also necessary to manually combine the clean and debris-covered parts into single glaciers. Additional input data for the post processing were Sentinel 2 images from the same time period, orthophotos from Land Information New Zealand (resolution: 0.75 m, date: Nov 2014), and the 1978/88 outlines from the GLIMS database (http://www.glims.org/). As the Sentinel 2 data were more heavily cloud covered compared to the Landsat 8 images, they were only used for post processing and not for the classification itself. Initial results show that New Zealand glaciers covered an area of about 1050 km² in 2016, a reduction of 16% since 1978. Approximately 17% of glacier area was covered in surface debris. The glaciers in the central Southern Alps around Mt Cook reduced in area by 24%. Glaciers in the North Island of New Zealand reduced by 71% since 1988, and only 2 km² of ice cover remained in 2016. Chinn, TJH (2001). "Distribution of the glacial water resources of New Zealand." Journal of Hydrology (NZ) 40(2): 139-187 Gjermundsen, EF, Mathieu, R, Kääb, A, Chinn, TJH, Fitzharris, B & Hagen, JO (2011). "Assessment of multispectral glacier mapping methods and

  1. OPTICAL FLOW FOR GLACIER MOTION ESTIMATION

    Directory of Open Access Journals (Sweden)

    C. Vogel

    2012-07-01

    Full Text Available Quantitative measurements of glacier flow over time are an important ingredient for glaciological research, for example to determine the mass balances and the evolution of glaciers. Measuring glacier flow in multi-temporal images involves the estimation of a dense set of corresponding points, which in turn define the flow vectors. Furthermore glaciers exhibit rather difficult radiometry, since their surface usually contains homogeneous areas as well as weak texture and contrast. To date glacier flow is usually observed by manually measuring a sparse set of correspondences, which is labor-intensive and often yields rather irregular point distributions, with the associated problems of interpolating over large areas. In the present work we propose to densely compute motion vectors at every pixel, by using recent robust methods for optic flow computation. Determining the optic flow, i.e. the dense deformation field between two images of a dynamic scene, has been a classic, long-standing research problem in computer vision and image processing. Sophisticated methods exist to optimally balance data fidelity with smoothness of the motion field. Depending on the strength of the local image gradients these methods yield a smooth trade-off between matching and interpolation, thereby avoiding the somewhat arbitrary decision which discrete anchor points to measure, while at the same time mitigating the problem of gross matching errors. We evaluate our method by comparing with manually measured point wise ground truth.

  2. Rock glaciers on South Shetland Islands, Antarctic Peninsula, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — In the South Shetland Islands the investigators found eight active rock glaciers, no relict or fossil examples, and seven protalus ramparts. The rock glaciers are...

  3. Climatic control on extreme sediment transfer from Dokriani Glacier ...

    Indian Academy of Sciences (India)

    glaciers have received more attention for the water resources management and hydropower develop- ment in the Himalayas ..... Glacier melt runoff represents the integrated basin response to various ..... for policy implementation; Him. Geol.

  4. Rock glaciers in the Pyrenees, Spain and France, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This study and inventory of active rock glaciers was carried out by means of the usual techniques used in the study of alpine permafrost. First, the rock glaciers...

  5. Can shrubs help to reconstruct historical glacier retreats?

    International Nuclear Information System (INIS)

    Buras, Allan; Hallinger, Martin; Wilmking, Martin

    2012-01-01

    In the 21st century, most of the world’s glaciers are expected to retreat due to further global warming. The range of this predicted retreat varies widely as a result of uncertainties in climate and glacier models. To calibrate and validate glacier models, past records of glacier mass balance are necessary, which often only span several decades. Long-term reconstructions of glacier mass balance could increase the precision of glacier models by providing the required calibration data. Here we show the possibility of applying shrub growth increments as an on-site proxy for glacier summer mass balance, exemplified by Salix shrubs in Finse, Norway. We further discuss the challenges which this method needs to meet and address the high potential of shrub growth increments for reconstructing glacier summer mass balance in remote areas. (letter)

  6. Monitoring of Gangotri glacier using remote sensing and ground ...

    Indian Academy of Sciences (India)

    for activating fast melting and affecting the glacier health significantly. Apart from climatic ... glacier health were also validated using high resolution satellite imageries and field visit. A deglaciation ...... Contribution of Work- ing Group I to the ...

  7. Modeled climate-induced glacier change in Glacier National Park, 1850-2100

    Science.gov (United States)

    Hall, M.H.P.; Fagre, D.B.

    2003-01-01

    The glaciers in the Blackfoot-Jackson Glacier Basin of Glacier National Park, Montana, decreased in area from 21.6 square kilometers (km2) in 1850 to 7.4 km2 in 1979. Over this same period global temperatures increased by 0.45??C (?? 0. 15??C). We analyzed the climatic causes and ecological consequences of glacier retreat by creating spatially explicit models of the creation and ablation of glaciers and of the response of vegetation to climate change. We determined the melt rate and spatial distribution of glaciers under two possible future climate scenarios, one based on carbon dioxide-induced global warming and the other on a linear temperature extrapolation. Under the former scenario, all glaciers in the basin will disappear by the year 2030, despite predicted increases in precipitation; under the latter, melting is slower. Using a second model, we analyzed vegetation responses to variations in soil moisture and increasing temperature in a complex alpine landscape and predicted where plant communities are likely to be located as conditions change.

  8. The Morsárjökull rock avalanche in the southern part of the Vatnajökull glacier, south Iceland

    Science.gov (United States)

    Sæmundsson, Şorsteinn; Sigurősson, Ingvar A.; Pétursson, Halldór G.; Decaulne, Armelle; Jónsson, Helgi P.

    2010-05-01

    and it is evident that since that time the glacier has retreated considerably and during the last decade the melting has been very rapid. It is thought that undercutting of the mountain slope by glacial erosion and the retreat of the glacier are the main contributing factors leading to the rock avalanche. The glacial erosion has destabilized the slope, which is mainly composed of palagonite and dolerite rocks, affected by geothermal alteration. Hence a subsequent fracture formation has weakened the strength of the bedrock. However the exact triggering factor is not known. No seismic activity or meteorological signal such as heavy rainfall or intensive snowmelt recorded prior to the rock avalanche which could be interpreted as triggering factors. From 2007 considerable changes have been observed on the glacier. The ice-front has retreated considerably and the debris lobe of the rock avalanche has moved downward along with the glacier ice about 90-100 m per year. The rocky material, by insulating the ice, has reduced its melting, leading to a relative "thickening" of the ice beneath the rock avalanche debris up to 11-15 m per year. After three melting seasons the debris mass was about 29 m above the surrounding ice surface.

  9. Terrestrial rock glaciers: a potential analog for Martian lobate flow features (LFF)

    Science.gov (United States)

    Sinha, Rishitosh K.; Vijayan, Sivaprahasam; Bharti, Rajiv R.

    2016-05-01

    Rock glaciers, regarded as cryospheric ice/water resource in the terrestrial-glacial systems based on their tongue/lobate-shaped flow characteristic and subsurface investigation using ground-penetrating radar. We examined the subsurface, geomorphology, climate-sensitivity and thermophysical properties of a Lobate Flow Feature (LFF) on Mars (30°-60° N and S hemispheres) to compare/assess the potentials of rock glaciers as an analog in suggesting LFFs to be a source of subsurface ice/water. LFFs are generally observed at the foot of impact craters' wall. HiRISE/CTX imageries from MRO spacecraft were used for geomorphological investigation of LFF using ArcMap-10.0 and subsurface investigation was carried out using data from MRO-SHARAD (shallow radar) after integrating with SiesWare-8.0. ENVI-5.0 was used to retrieve thermophysical properties of LFF from nighttime datasets (12.57 μm) acquired by THEMIS instrument-onboard the Mars Odyssey spacecraft and derive LFFs morphometry from MOLA altimeter point tracks onboard MGS spacecraft. Integrating crater chronology tool (Craterstats) with Arc Map, we have derived the formation age of LFF. Our investigation and comparison of LFF to rock glaciers revealed: (1) LFFs have preserved ice at depth 50m as revealed from SHARAD radargram and top-layer composed of rocky-debris material with thermal inertia ( 300-350 Jm-2 K-1s-1/2). (2) LFF formation age ( 10-100 Ma) corresponds to moderate scale debris covered glaciation of a shorter-span suggesting high sensitivity to obliquity-driven climatic shifts. (3) Presence of polygon cracks and high linear-arcuate furrow-and-ridges on the surface indicates presence of buried ice. This work is a significant step towards suggesting LFF to be a potential source of present-day stored ice/water on Mars.

  10. Circum-Arctic Changes in the Flow of Glaciers and Ice Caps from Satellite SAR Data between the 1990s and 2017

    Directory of Open Access Journals (Sweden)

    Tazio Strozzi

    2017-09-01

    Full Text Available We computed circum-Arctic surface velocity maps of glaciers and ice caps over the Canadian Arctic, Svalbard and the Russian Arctic for at least two times between the 1990s and 2017 using satellite SAR data. Our analyses are mainly performed with offset-tracking of ALOS-1 PALSAR-1 (2007–2011 and Sentinel-1 (2015–2017 data. In certain cases JERS-1 SAR (1994–1998, TerraSAR-X (2008–2012, Radarsat-2 (2009–2016 and ALOS-2 PALSAR-2 (2015–2016 data were used to fill-in spatial or temporal gaps. Validation of the latest Sentinel-1 results was accomplished by means of SAR data at higher spatial resolution (Radarsat-2 Wide Ultra Fine and ground-based measurements. In general, we observe a deceleration of flow velocities for the major tidewater glaciers in the Canadian Arctic and an increase in frontal velocity along with a retreat of frontal positions over Svalbard and the Russian Arctic. However, all regions have strong accelerations for selected glaciers. The latter developments can be well traced based on the very high temporal sampling of Sentinel-1 acquisitions since 2015, revealing new insights in glacier dynamics. For example, surges on Spitsbergen (e.g., Negribreen, Nathorsbreen, Penckbreen and Strongbreen have a different characteristic and timing than those over Eastern Austfonna and Edgeoya (e.g., Basin 3, Basin 2 and Stonebreen. Events similar to those ongoing on Eastern Austofonna were also observed over the Vavilov Ice Cap on Severnaya Zemlya and possibly Simony Glacier on Franz-Josef Land. Collectively, there seems to be a recently increasing number of glaciers with frontal destabilization over Eastern Svalbard and the Russian Arctic compared to the 1990s.

  11. Using marine sediment archives to reconstruct past outlet glacier variability

    DEFF Research Database (Denmark)

    Andresen, Camilla Snowman; Straneo, Fiamma; Ribergaard, Mads

    2013-01-01

    Ice-rafted debris in fjord sediment cores provides information about outlet glacier activity beyond the instrumental time period. It tells us that the Helheim Glacier, Greenland’s third most productive glacier, responds rapidly to short-term (3 to 10 years) climate changes....

  12. Determining glacier velocity with single frequency GPS receivers

    NARCIS (Netherlands)

    Reijmer, C.H.; van de Wal, R.S.W.; Boot, W.

    2011-01-01

    A well-known phenomenon in glacier dynamics is the existence of a relation between the glacier velocity and available amount of melt water (Zwally et al., 2002; Van de Wal et al., 2008). This relation is of particular importance when estimating the reaction of glaciers and ice sheets to climate

  13. Tidal Movement of Nioghalvfjerdsfjorden Glacier, Northeast Greenland: Observations and Modelling

    DEFF Research Database (Denmark)

    Reeh, Niels; Mayer, C.; Olesen, O. B.

    2000-01-01

    Nioghalvfjerdsfjorden glacier is a > 60 km long and 20 km wide floating outlet glacier located at 79 degrees 30' N, 22 degrees W, draining a large area of the northeast Greenland ice sheet. Climate, mass-balance and dynamics studies were carried out on the glacier in three field seasons in 1996...

  14. Climate reconstructions derived from global glacier length records

    NARCIS (Netherlands)

    Klok, E.J.; Oerlemans, J.

    2004-01-01

    As glacier length fluctuations provide useful information about past climate, we derived historic fluctuations in the equilibrium-line altitude (ELA) on the basis of 19 glacier length records from different parts of the world. We used a model that takes into account the geometry of the glacier,

  15. Release fractions for Rocky Flats specific accidents

    International Nuclear Information System (INIS)

    Weiss, R.C.

    1992-01-01

    As Rocky Flats and other DOE facilities begin the transition process towards decommissioning, the nature of the scenarios to be studied in safety analysis will change. Whereas the previous emphasis in safety accidents related to production, now the emphasis is shifting to accidents related tc decommissioning and waste management. Accident scenarios of concern at Rocky Flats now include situations of a different nature and different scale than are represented by most of the existing experimental accident data. This presentation will discuss approaches at sign to use for applying the existing body of release fraction data to this new emphasis. Mention will also be made of ongoing efforts to produce new data and improve the understanding of physical mechanisms involved

  16. History of Rocky Flats waste streams

    International Nuclear Information System (INIS)

    Luckett, L.L.; Dickman, A.A.; Wells, C.R.; Vickery, D.J.

    1982-01-01

    An analysis of the waste streams at Rocky Flats was done to provide information for the Waste Certification program. This program has involved studying the types and amounts of retrievable transuranic (TRU) waste from Rocky Flats that is stored at the Idaho National Engineering Laboratory (INEL). The information can be used to estimate the types and amounts of waste that will need to be permanently stored in the Waste Isolation Pilot Plant (WIPP). The study covered mostly the eight-year period from June 1971 to June 1979. The types, amounts, and plutonium content of TRU waste and the areas or operations responsible for generating the waste are summarized in this waste stream history report. From the period studied, a total of 24,546,153 lbs of waste containing 211,148 g of plutonium currently occupies 709,497 cu ft of storage space at INEL

  17. Rocky Flats cleanup receives new deadline

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The Rocky Flats nuclear weapon plant near Denver narrowly missed a court-ordered shutdown of virtually all cleanup activities when it failed to meet an Aug. 22 deadline for a state permit to store mixed radioactive and hazardous wastes on site. US District Court Judge Lewis Babcock granted a 90-day stay of contempt charges against the US Dept. of Energy, but left open the possibility of civil penalties under the Resource Conservation and Recovery Act. DOE's problems stem from a lawsuit the Sierra Club won two years ago in which Babcock gave Rocky Flats until Aug. 22 to obtain a RCRA permit or interim status from Colorado to store 600 cu yd of mixed wastes. If DOE failed to do so, the court said it could not generate further hazardous wastes at the site

  18. Rocky Mountain spotted fever: a clinician's dilemma.

    Science.gov (United States)

    Masters, Edwin J; Olson, Gary S; Weiner, Scott J; Paddock, Christopher D

    2003-04-14

    Rocky Mountain spotted fever is still the most lethal tick-vectored illness in the United States. We examine the dilemmas facing the clinician who is evaluating the patient with possible Rocky Mountain spotted fever, with particular attention to the following 8 pitfalls in diagnosis and treatment: (1) waiting for a petechial rash to develop before diagnosis; (2) misdiagnosing as gastroenteritis; (3) discounting a diagnosis when there is no history of a tick bite; (4) using an inappropriate geographic exclusion; (5) using an inappropriate seasonal exclusion; (6) failing to treat on clinical suspicion; (7) failing to elicit an appropriate history; and (8) failing to treat with doxycycline. Early diagnosis and proper treatment save lives.

  19. A possible climate signal in the surface morphology and internal structure of Galena Creek Rock Glacier, Wyoming

    Science.gov (United States)

    Petersen, Eric; Holt, John; Levy, Joseph; Stuurman, Cassie; Nerozzi, Stefano; Cardenas, Benjamin; Pharr, James; Aylward, Dan; Schmidt, Logan; Hoey, William; Prem, Parvathy; Rambo, Jackie; Lim, YeJin; Maharaj, Kian

    2016-04-01

    Galena Creek Rock Glacier (GCRG) has been shown in previous studies to be a debris-covered glacier (e.g. Ackert, Jr., 1998), and is thus a target of interest as a record of climate and an element of the mountain hydrological system. The goal of this study was to investigate possible relationships between surface morphology and internal structure and composition of GCRG. This was achieved using ground-penetrating radar (GPR), time-domain electromagnetic sounding (TEM), and photogrammetry to produce digital terrain models (DTMs). We acquired 6 longitudinal GPR surveys at 50 and 100 MHz, 2 common midpoint GPR surveys, and 28 TEM soundings on GCRG from the head to the toe, and ground-based photogrammetry data were collected to produce a DTM of its cirque at 10 cm resolution. TEM soundings locally constrained the bulk thickness of GCRG to 26-75 meters. Common midpoint and hyperbola analyses of GPR surveys produced dielectric constants in the near subsurface of 4 in the upper glacier to 5-9 in the middle and lower glacier. These are consistent with clean ice and a mélange of rock with air and/or ice, respectively. GPR revealed a pervasive shallow reflector at 1-2.5m depth that we interpret to be the interface between the surface debris layer and glacier ice. There is increased structure and clutter in the GPR data beneath this interface as one moves down glacier. Observations were additionally made of a 40m wide, 4-5m deep circular thermokarst pond located on upper GCRG in the cirque. The walls of the pond revealed a cross-section of the top several meters of GCRG's interior: a dry surface layer of rocky debris 1-1.5m thick overlying pure glacier ice. An englacial debris band was also observed, roughly 50 cm thick and presenting at an apparent up-glacier dip of ~30 degrees, intersecting the surface near a subtle ridge resolved in the photogrammetry DTM. A GPR transect conducted near the pond over 6 similar ridges imaged 6 corresponding up-glacier dipping reflectors that

  20. THERMODYNAMIC LIMITS ON MAGNETODYNAMOS IN ROCKY EXOPLANETS

    International Nuclear Information System (INIS)

    Gaidos, Eric; Conrad, Clinton P.; Manga, Michael; Hernlund, John

    2010-01-01

    To ascertain whether magnetic dynamos operate in rocky exoplanets more massive or hotter than the Earth, we developed a parametric model of a differentiated rocky planet and its thermal evolution. Our model reproduces the established properties of Earth's interior and magnetic field at the present time. When applied to Venus, assuming that planet lacks plate tectonics and has a dehydrated mantle with an elevated viscosity, the model shows that the dynamo shuts down or never operated. Our model predicts that at a fixed planet mass, dynamo history is sensitive to core size, but not to the initial inventory of long-lived, heat-producing radionuclides. It predicts that rocky planets larger than 2.5 Earth masses will not develop inner cores because the temperature-pressure slope of the iron solidus becomes flatter than that of the core adiabat. Instead, iron 'snow' will condense near or at the top of these cores, and the net transfer of latent heat upward will suppress convection and a dynamo. More massive planets can have anemic dynamos due to core cooling, but only if they have mobile lids (plate tectonics). The lifetime of these dynamos is shorter with increasing planet mass but longer with higher surface temperature. Massive Venus-like planets with stagnant lids and more viscous mantles will lack dynamos altogether. We identify two alternative sources of magnetic fields on rocky planets: eddy currents induced in the hot or molten upper layers of planets on very short-period orbits, and dynamos in the ionic conducting layers of 'ocean' planets with ∼10% mass in an upper mantle of water (ice).

  1. Basic TRUEX process for Rocky Flats Plant

    International Nuclear Information System (INIS)

    Leonard, R.A.; Chamberlain, D.B.; Dow, J.A.; Farley, S.E.; Nunez, L.; Regalbuto, M.C.; Vandegrift, G.F.

    1994-08-01

    The Generic TRUEX Model was used to develop a TRUEX process flowsheet for recovering the transuranics (Pu, Am) from a nitrate waste stream at Rocky Flats Plant. The process was designed so that it is relatively insensitive to changes in process feed concentrations and flow rates. Related issues are considered, including solvent losses, feed analysis requirements, safety, and interaction with an evaporator system for nitric acid recycle

  2. Microwave solidification development for Rocky Flats waste

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, D.; Erle, R.; Eschen, V. [and others

    1994-04-01

    The Microwave Engineering Team at the Rocky Flats Plant has developed a production-scale system for the treatment of hazardous, radioactive, and mixed wastes using microwave energy. The system produces a vitreous final form which meets the acceptance criteria for shipment and disposal. The technology also has potential for application on various other waste streams from the public and private sectors. Technology transfer opportunities are being identified and pursued for commercialization of the microwave solidification technology.

  3. Microwave solidification development for Rocky Flats waste

    International Nuclear Information System (INIS)

    Dixon, D.; Erle, R.; Eschen, V.

    1994-04-01

    The Microwave Engineering Team at the Rocky Flats Plant has developed a production-scale system for the treatment of hazardous, radioactive, and mixed wastes using microwave energy. The system produces a vitreous final form which meets the acceptance criteria for shipment and disposal. The technology also has potential for application on various other waste streams from the public and private sectors. Technology transfer opportunities are being identified and pursued for commercialization of the microwave solidification technology

  4. The distribution and abundance ofa nuisance native alga, Didymosphenia geminata,in streams of Glacier National Park: Climate drivers and management implications

    Science.gov (United States)

    Muhlfeld, Clint C.; Jones, Leslie A.; E. William Schweiger,; Isabel W. Ashton,; Loren L. Bahls,

    2011-01-01

    Didymosphenia geminata (didymo) is a freshwater alga native to North America, including Glacier National Park, Montana. It has long been considered a cold-water species, but has recently spread to lower latitudes and warmer waters, and increasingly forms large blooms that cover streambeds. We used a comprehensive monitoring data set from the National Park Service (NPS) and USGS models of stream temperatures to explore the drivers of didymo abundance in Glacier National Park. We estimate that approximately 64% of the stream length in the park contains didymo, with around 5% in a bloom state. Results suggest that didymo abundance likely increased over the study period (2007–2009), with blooms becoming more common. Our models suggest that didymo abundance is positively related to summer stream temperatures and negatively related to total nitrogen and the distance downstream from lakes. Regional climate model simulations indicate that stream temperatures in the park will likely continue to increase over the coming decades, which may increase the extent and severity of didymo blooms. As a result, didymo may be a useful indicator of thermal and hydrological modification associated with climate warming, especially in a relatively pristine system like Glacier where proximate human-related disturbances are absent or reduced. Glacier National Park plays an important role as a sentinel for climate change and associated education across the Rocky Mountain region.

  5. The distribution and abundance of a nuisance native alga, Didymosphen Didymosphenia geminata, in streams of Glacier National Park: Climate drivers and management implications

    Science.gov (United States)

    William, Schweiger E.; Ashton, I.W.; Muhlfeld, C.C.; Jones, L.A.; Bahls, L.L.

    2011-01-01

    Didymosphenia geminata (didymo) is a freshwater alga native to North America, including Glacier National Park, Montana. It has long been considered a cold-water species, but has recently spread to lower latitudes and warmer waters, and increasingly forms large blooms that cover streambeds. We used a comprehensive monitoring data set from the National Park Service (NPS) and USGS models of stream temperatures to explore the drivers of didymo abundance in Glacier National Park. We estimate that approximately 64% of the stream length in the park contains didymo, with around 5% in a bloom state. Results suggest that didymo abundance likely increased over the study period (2007-2009), with blooms becoming more common. Our models suggest that didymo abundance is positively related to summer stream temperatures and negatively related to total nitrogen and the distance downstream from lakes. Regional climate model simulations indicate that stream temperatures in the park will likely continue to increase over the coming decades, which may increase the extent and severity of didymo blooms. As a result, didymo may be a useful indicator of thermal and hydrological modification associated with climate warming, especially in a relatively pristine system like Glacier where proximate human-related disturbances are absent or reduced. Glacier National Park plays an important role as a sentinel for climate change and associated education across the Rocky Mountain region.

  6. Seismological observations of glaciers dynamic on the Spitsbergen archipelago

    Directory of Open Access Journals (Sweden)

    Fedorov A. V.

    2016-03-01

    Full Text Available The paper provides a brief description of results of Spitsbergen glacier observations by the seismic method. The study has been carried out both by permanent and temporary stations data. Characteristic features of glacier-related seismic events have been shown. Main areas of glacier seismic activity on the Archipelago have been revealed. A detailed study of Horsund-fjord glacier activity has been carried out using local seismic station HSPB data. Temporal and spatial distributions of glacier-related events have been obtained for the area. Season variations in temporal distribution of the events have been found

  7. Symposium 9: Rocky Mountain futures: preserving, utilizing, and sustaining Rocky Mountain ecosystems

    Science.gov (United States)

    Baron, Jill S.; Seastedt, Timothy; Fagre, Daniel B.; Hicke, Jeffrey A.; Tomback, Diana; Garcia, Elizabeth; Bowen, Zachary H.; Logan, Jesse A.

    2013-01-01

    In 2002 we published Rocky Mountain Futures, an Ecological Perspective (Island Press) to examine the cumulative ecological effects of human activity in the Rocky Mountains. We concluded that multiple local activities concerning land use, hydrologic manipulation, and resource extraction have altered ecosystems, although there were examples where the “tyranny of small decisions” worked in a positive way toward more sustainable coupled human/environment interactions. Superimposed on local change was climate change, atmospheric deposition of nitrogen and other pollutants, regional population growth, and some national management policies such as fire suppression.

  8. Canadian nuclear risk experience

    International Nuclear Information System (INIS)

    Hamel, P.E.

    1982-05-01

    Risk assessment in the Canadian nuclear fuel cycle is a very important and complex subject. Many levels of government are involved in deciding the acceptable limits for the risks, taking into account the benefits for society [fr

  9. A complex relationship between calving glaciers and climate

    Science.gov (United States)

    Post, A.; O'Neel, S.; Motyka, R.J.; Streveler, G.

    2011-01-01

    Many terrestrial glaciers are sensitive indicators of past and present climate change as atmospheric temperature and snowfall modulate glacier volume. However, climate interpretations based on glacier behavior require careful selection of representative glaciers, as was recently pointed out for surging and debris-covered glaciers, whose behavior often defies regional glacier response to climate [Yde and Paasche, 2010]. Tidewater calving glaciers (TWGs)mountain glaciers whose termini reach the sea and are generally grounded on the seaflooralso fall into the category of non-representative glaciers because the regional-scale asynchronous behavior of these glaciers clouds their complex relationship with climate. TWGs span the globe; they can be found both fringing ice sheets and in high-latitude regions of each hemisphere. TWGs are known to exhibit cyclic behavior, characterized by slow advance and rapid, unstable retreat, largely independent of short-term climate forcing. This so-called TWG cycle, first described by Post [1975], provides a solid foundation upon which modern investigations of TWG stability are built. Scientific understanding has developed rapidly as a result of the initial recognition of their asynchronous cyclicity, rendering greater insight into the hierarchy of processes controlling regional behavior. This has improved the descriptions of the strong dynamic feedbacks present during retreat, the role of the ocean in TWG dynamics, and the similarities and differences between TWG and ice sheet outlet glaciers that can often support floating tongues.

  10. Criteria impacting shipments of Rocky Flats Plant radioactive mixed wastes

    International Nuclear Information System (INIS)

    Clawson, R.L.; Eide, J.H.

    1992-05-01

    Westinghouse Hanford Company, Transportation and Packaging Division, under contract for the Los Alamos Technology Office-Rocky Flats Plant, has developed this synopsis report to be used as a reference in the development of the Rocky Flats Plant Comprehensive Treatment and Management Plan and the Rocky Flats Plant Residue Elimination Plan. This report represents the criteria for packaging, shipping, and transporting Rocky Flats Plant radioactive mixed wastes. It is a compilation of state and federal regulations, US Department of Energy orders, and acceptance criteria specific to US Department of Energy radioactive mixed waste treatment, storage and disposal facilities

  11. Fording Canadian Coal Trust

    Energy Technology Data Exchange (ETDEWEB)

    Popowich, J.; Millos, R. [Elk Valley Coal Corporation, Calgary, AB (Canada)

    2004-07-01

    This is the first of five slide/overhead presentations presented at the Fording Canadian Coal Trust and Tech Cominco Ltd. investor day and mine tour. The Fording Canadian Coal Trust is described. The Trust's assets comprise six Elk Valley metallurgical coal mines and six wollastonite operations (in the NYCO Group). Trust structure, corporate responsibility, organizational structure, reserves and resources, management philosophy, operating strategies, steel market dynamics, coal market, production expansion, sales and distribution are outlined. 15 figs., 5 tabs.

  12. A Facies Model for Temperate Continental Glaciers.

    Science.gov (United States)

    Ashley, Gail Mowry

    1987-01-01

    Discusses the presence and dynamics of continental glaciers in the domination of the physical processes of erosion and deposition in the mid-latitudes during the Pleistocene period. Describes the use of a sedimentary facies model as a guide to recognizing ancient temperate continental glacial deposits. (TW)

  13. Pattern of Glacier Recession in Indian Himalaya

    Science.gov (United States)

    Singh, Ajay; Patwardhan, Anand

    All currently available climate models predict a near-surface warming trend under the influence of rising levels of greenhouse gases in the atmosphere. In addition to the direct effects on climate — for example, on the frequency of heat waves — this increase in surface temperatures has important consequences for the cryosphere subsequently hydrological cycle, particularly in regions where water supply is currently dominated by melting snow or ice. The Indian Himalayan region occupies a special place in the mountain ecosystems of the world. These geodynamically young mountains are not only important from the standpoint of climate and as a provider of life, giving water to a large part of the Indian subcontinent, but they also harbor a rich variety of flora, fauna, human communities and cultural diversity. Glaciers in this region are changing in area as well as in volume like those in other parts of the world. Studies have been carried out for recession in some of these glaciers using remote sensing as well as field observation techniques. Spatiotemporal pattern in the recession rate of the studied glaciers has been presented in this paper. Plausible causes for the recession have been also discussed. Finally, future scopes for observation and analysis in glaciers recession have been suggested.

  14. The Greater Caucasus Glacier Inventory (Russia, Georgia and Azerbaijan)

    Science.gov (United States)

    Tielidze, Levan G.; Wheate, Roger D.

    2018-01-01

    There have been numerous studies of glaciers in the Greater Caucasus, but none that have generated a modern glacier database across the whole mountain range. Here, we present an updated and expanded glacier inventory at three time periods (1960, 1986, 2014) covering the entire Greater Caucasus. Large-scale topographic maps and satellite imagery (Corona, Landsat 5, Landsat 8 and ASTER) were used to conduct a remote-sensing survey of glacier change, and the 30 m resolution Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model (ASTER GDEM; 17 November 2011) was used to determine the aspect, slope and height distribution of glaciers. Glacier margins were mapped manually and reveal that in 1960 the mountains contained 2349 glaciers with a total glacier surface area of 1674.9 ± 70.4 km2. By 1986, glacier surface area had decreased to 1482.1 ± 64.4 km2 (2209 glaciers), and by 2014 to 1193.2 ± 54.0 km2 (2020 glaciers). This represents a 28.8 ± 4.4 % (481 ± 21.2 km2) or 0.53 % yr-1 reduction in total glacier surface area between 1960 and 2014 and an increase in the rate of area loss since 1986 (0.69 % yr-1) compared to 1960-1986 (0.44 % yr-1). Glacier mean size decreased from 0.70 km2 in 1960 to 0.66 km2 in 1986 and to 0.57 km2 in 2014. This new glacier inventory has been submitted to the Global Land Ice Measurements from Space (GLIMS) database and can be used as a basis data set for future studies.

  15. Glaciers along proposed routes extending the Copper River Highway, Alaska

    Science.gov (United States)

    Glass, R.L.

    1996-01-01

    Three inland highway routes are being considered by the Alaska Department of Transportation and Public Facilities to connect the community of Cordova in southcentral Alaska to a statewide road system. The routes use part of a Copper River and Northwest Railway alignment along the Copper River through mountainous terrain having numerous glaciers. An advance of any of several glaciers could block and destroy the roadway, whereas retreating glaciers expose large quantities of unconsolidated, unvegetated, and commonly ice-rich sediments. The purpose of this study was to map historical locations of glacier termini near these routes and to describe hazards associated with glaciers and seasonal snow. Historical and recent locations of glacier termini along the proposed Copper River Highway routes were determined by reviewing reports and maps and by interpreting aerial photographs. The termini of Childs, Grinnell, Tasnuna, and Woodworth Glaciers were 1 mile or less from a proposed route in the most recently available aerial photography (1978-91); the termini of Allen, Heney, and Schwan Glaciers were 1.5 miles or less from a proposed route. In general, since 1911, most glaciers have slowly retreated, but many glaciers have had occasional advances. Deserted Glacier and one of its tributary glaciers have surge-type medial moraines, indicating potential rapid advances. The terminus of Deserted Glacier was about 2.1 miles from a proposed route in 1978, but showed no evidence of surging. Snow and rock avalanches and snowdrifts are common along the proposed routes and will periodically obstruct the roadway. Floods from ice-dammed lakes also pose a threat. For example, Van Cleve Lake, adjacent to Miles Glacier, is as large as 4.4 square miles and empties about every 6 years. Floods from drainages of Van Cleve Lake have caused the Copper River to rise on the order of 20 feet at Million Dollar Bridge.

  16. Changes in the Surface Area of Glaciers in Northern Eurasia

    Science.gov (United States)

    Khromova, T.; Nosenko, G.

    2012-12-01

    Glaciers are widely recognized as key indicators of climate change. Recent evidence suggests an acceleration of glacier mass loss in several key mountain regions. Glacier recession implies the landscape changes in the glacial zone, origin of new lakes and activation of natural disaster processes, catastrophic mudflows, ice avalanches, outburst floods, and etc. The presence of glaciers in itself threats to human life, economic activity and growing infrastructure. Economical and recreational human activity in mountain regions requires relevant information on snow and ice objects. Absence or inadequacy of such information results in financial and human losses. A more comprehensive evaluation of glacier changes is imperative to assess ice contributions to global sea level rise and the future of water resources from glacial basins. One of the urgent steps is a full inventory of all ice bodies, their volume and changes The first estimation of glaciers state and glaciers distribution in the big part of Northern Eurasia has been done in the USSR Glacier Inventory published in 1966 -1980 as a part of IHD activity. The Inventory is based on topographic maps and air photos and reflects the status of the glaciers in 1957-1970y. There is information about 23796 glaciers with area of 78222.3 km2 in the Inventory. It covers 23 glacier systems on Northern Eurasia. In the 80th the USSR Glacier Inventory has been transformed in the digital form as a part of the World Glacier Inventory. Recent satellite data provide a unique opportunity to look again at these glaciers and to evaluate changes in glacier extent for the second part of XX century. In the paper we report about 15 000 glaciers outlines for Caucasus, Pamir, Tien-Shan, Altai, Syntar-Khayata, Cherskogo Range, Kamchatka and Russian Arctic which have been derived from ASTER and Landsat imagery and could be used for glacier changes evaluation. The results show that glaciers are retreating in all these regions. There is, however

  17. Grounding line processes on the Totten Glacier

    Science.gov (United States)

    Cook, S.; Watson, C. S.; Galton-Fenzi, B.; Peters, L. E.; Coleman, R.

    2017-12-01

    The Totten Glacier has been an area of recent interest due to its large drainage basin, much of which is grounded below sea level and has a history of large scale grounding line movement. Reports that warm water reaches the sub-ice shelf cavity have led to speculation that it could be vulnerable to future grounding line retreat. Over the Antarctic summer 2016/17 an array of 6 GPS and autonomous phase-sensitive radar (ApRES) units were deployed in the grounding zone of the Totten Glacier. These instruments measure changes in ice velocity and thickness which can be used to investigate both ice dynamics across the grounding line, and the interaction between ice and ocean in the subglacial cavity. Basal melt rates calculated from the ApRES units on floating ice range from 1 to 17 m/a. These values are significantly lower than previous estimates of basal melt rate produced by ocean modelling of the subglacial cavity. Meanwhile, GPS-derived velocity and elevation on the surface of the ice show a strong tidal signal, as does the vertical strain rate within the ice derived from internal layering from the ApRES instruments. These results demonstrate the significance of the complex grounding pattern of the Totten Glacier. The presence of re-grounding points has significant implications for the dynamics of the glacier and the ocean circulation within the subglacial cavity. We discuss what can be learned from our in situ measurements, and how they can be used to improve models of the glacier's future behaviour.

  18. 2017 Rapid Retreat Of Thwaites Glacier

    Science.gov (United States)

    Milillo, P.; Rignot, E. J.; Mouginot, J.; Scheuchl, B.

    2017-12-01

    We employ data from the second generation of SAR systems e.g. the Italian COSMO- SkyMed (CSK) constellation and the German TanDEM-X (TDX) formation to monitor grounding line retreat using short repeat-time interferometry and accurate InSAR DEM on Thwaites glacier in the Amundsen Sea Embayment (ASE), West Antarctica. The ASE is a marine-based ice sheet with a retrograde bed containing enough ice to raise global sea level by 120 cm. Several studies have inferred the mechanical properties of portions of ASE using observationally constrained numerical models, but these studies offer only temporal snapshots of basal mechanics owing to a dearth of observational time series. Prior attempts of grounding lines mapping have been limited because few space-borne SAR missions offer the short-term repeat pass capability required to map the differential vertical displacement of floating ice at tidal frequencies with sufficient detail to resolve grounding line boundaries in areas of fast ice deformation. Using 1-day CSK repeat pass data and TDX DEMs, we collected frequent, high-resolution grounding line measurements of Thwaites glaciers spanning 2015-2017. We compare the results with ERS data spanning 1996-2011, and Sentinel-1a 2014-2015 data. Between 2011 and 2017 we observe a maximum retreat of 5-7 km across the main Thwaites glacier tongue and Thwaites Eastern ice shelf (TEIS) corresponding to an increased retreat rate of 0.5 km/yr. Grounding line retreat has been fueled by the enhanced intrusion of warm, salty, subsurface ocean water of circumpolar deep water origin onto the continental shelf, beneath the floating ice shelf, to reach the glacier grounding zone and melt it from below at rates varying from 50 to 150 m/yr. The retreat rate varies depending on the magnitude of ice melt by the ocean, the rate of ice thinning and the shape of the glacier surface and bed topography.

  19. Quaternary sediment thickness and bedrock topography of the glaciated United States east of the Rocky Mountains

    Science.gov (United States)

    Soller, David R.; Garrity, Christopher P.

    2018-01-26

    Beginning roughly 2.6 million years ago, global climate entered a cooling phase known as the Pleistocene Epoch. As snow in northern latitudes compacted into ice several kilometers thick, it flowed as glaciers southward across the North American continent. These glaciers extended across the northern United States, dramatically altering the landscape they covered. East of the Rocky Mountains, the ice coalesced into continental glaciers (called the Laurentide Ice Sheet) that at times blanketed much of the north-central and northeastern United States. To the west of the Laurentide Ice Sheet, glaciers formed in the mountains of western Canada and the United States and coalesced into the Cordilleran ice sheet; this relatively smaller ice mass extended into the conterminous United States in the northernmost areas of western Montana, Idaho, and Washington. Throughout the Pleistocene, landscape alteration occurred by (1) glacial erosion of the rocks and sediments; (2) redeposition of the eroded earth materials in a form substantially different from their source rocks, in terms of texture and overall character; and (3) disruption of preexisting drainage patterns by the newly deposited sediments. In many cases, pre-glacial drainage systems (including, for example, the Mississippi River) were rerouted because their older drainage courses became blocked with glacial sediment.The continental glaciers advanced and retreated many times across those areas. During each ice advance, or glaciation, erosion and deposition occurred, and the landscape was again altered. Through successive glaciations, the landscape and the bedrock surface gradually came to resemble their present configurations. As continental ice sheets receded and the Pleistocene ended, erosion and deposition of sediment (for example in stream valleys) continued to shape the landscape up to the present day (albeit to a lesser extent than during glaciation). The interval of time since the last recession of the glaciers

  20. Surge of a Complex Glacier System - The Current Surge of the Bering-Bagley Glacier System, Alaska

    Science.gov (United States)

    Herzfeld, U. C.; McDonald, B.; Trantow, T.; Hale, G.; Stachura, M.; Weltman, A.; Sears, T.

    2013-12-01

    Understanding fast glacier flow and glacial accelerations is important for understanding changes in the cryosphere and ultimately in sea level. Surge-type glaciers are one of four types of fast-flowing glaciers --- the other three being continuously fast-flowing glaciers, fjord glaciers and ice streams --- and the one that has seen the least amount of research. The Bering-Bagley Glacier System, Alaska, the largest glacier system in North America, surged in 2011 and 2012. Velocities decreased towards the end of 2011, while the surge kinematics continued to expand. A new surge phase started in summer and fall 2012. In this paper, we report results from airborne observations collected in September 2011, June/July and September/October 2012 and in 2013. Airborne observations include simultaneously collected laser altimeter data, videographic data, GPS data and photographic data and are complemented by satellite data analysis. Methods range from classic interpretation of imagery to analysis and classification of laser altimeter data and connectionist (neural-net) geostatistical classification of concurrent airborne imagery. Results focus on the characteristics of surge progression in a large and complex glacier system (as opposed to a small glacier with relatively simple geometry). We evaluate changes in surface elevations including mass transfer and sudden drawdowns, crevasse types, accelerations and changes in the supra-glacial and englacial hydrologic system. Supraglacial water in Bering Glacier during Surge, July 2012 Airborne laser altimeter profile across major rift in central Bering Glacier, Sept 2011

  1. Measuring Surface Deformation in Glacier Retreated Areas Based on Ps-Insar - Geladandong Glacier as a Case Study

    Science.gov (United States)

    Mohamadi, B.; Balz, T.

    2018-04-01

    Glaciers are retreating in many parts of the world as a result of global warming. Many researchers consider Qinghai-Tibetan Plateau as a reference for climate change by measuring glaciers retreat on the plateau. This retreat resulted in some topographic changes in retreated areas, and in some cases can lead to geohazards as landslides, and rock avalanches, which is known in glacier retreated areas as paraglacial slope failure (PSF). In this study, Geladandong biggest and main glacier mass was selected to estimate surface deformation on its glacier retreated areas and define potential future PSF based on PS-InSAR technique. 56 ascending and 49 descending images were used to fulfill this aim. Geladandong glacier retreated areas were defined based on the maximum extent of the glacier in the little ice age. Results revealed a general uplift in the glacier retreated areas with velocity less than 5mm/year. Obvious surface motion was revealed in seven parts surround glacier retreated areas with high relative velocity reached ±60mm/year in some parts. Four parts were considered as PSF potential motion, and two of them showed potential damage for the main road in the study area in case of rock avalanche into recent glacier lakes that could result in glacier lake outburst flooding heading directly to the road. Finally, further analysis and field investigations are needed to define the main reasons for different types of deformation and estimate future risks of these types of surface motion in the Qinghai-Tibetan Plateau.

  2. Modelling glacier-bed overdeepenings and possible future lakes for the glaciers in the Himalaya-Karakoram region

    DEFF Research Database (Denmark)

    Linsbauer, A.; Frey, H.; Haeberli, W.

    2016-01-01

    Surface digital elevation models (DEMs) and slope-related estimates of glacier thickness enable modelling of glacier-bed topographies over large ice-covered areas. Due to the erosive power of glaciers, such bed topographies can contain numerous overdeepenings, which when exposed following glacier...... retreat may fill with water and form new lakes. In this study, the bed overdeepenings for ∼28000 glaciers (40 775km2) of the Himalaya-Karakoram region are modelled using GlabTop2 (Glacier Bed Topography model version 2), in which ice thickness is inferred from surface slope by parameterizing basal shear...... stress as a function of elevation range for each glacier. The modelled ice thicknesses are uncertain (±30%), but spatial patterns of ice thickness and bed elevation primarily depend on surface slopes as derived from the DEM and, hence, are more robust. About 16 000 overdeepenings larger than 104m2 were...

  3. Geophysical Investigations of Hypersaline Subglacial Water Systems in the Canadian Arctic: A Planetary Analog

    Science.gov (United States)

    Rutishauser, A.; Sharp, M. J.; Blankenship, D. D.; Skidmore, M. L.; Grima, C.; Schroeder, D. M.; Greenbaum, J. S.; Dowdeswell, J. A.; Young, D. A.

    2017-12-01

    Robotic exploration and remote sensing of the solar system have identified the presence of liquid water beneath ice on several planetary bodies, with evidence for elevated salinity in certain cases. Subglacial water systems beneath Earth's glaciers and ice sheets may provide terrestrial analogs for microbial habitats in such extreme environments, especially those with higher salinity. Geological data suggest that several ice caps and glaciers in the eastern Canadian High Arctic are partially underlain by evaporite-rich sedimentary rocks, and subglacial weathering of these rocks is potentially conducive to the formation of hypersaline subglacial waters. Here, we combine airborne geophysical data with geological constraints to identify and characterize hypersaline subglacial water systems beneath ice caps in Canada's Queen Elizabeth Islands. High relative bedrock reflectivity and specularity anomalies that are apparent in radio-echo sounding data indicate multiple locations where subglacial water is present in areas where modeled ice temperatures at the glacier bed are well below the pressure melting point. This suggests that these water systems are hypersaline, with solute concentrations that significantly depress the freezing point of water. From combined interpretations of geological and airborne-magnetic data, we define the geological context within which these systems have developed, and identify possible solute-sources for the inferred brine-rich water systems. We also derive subglacial hydraulic potential gradients using airborne laser altimetry and ice thickness data, and apply water routing models to derive subglacial drainage pathways. These allow us to identify marine-terminating glaciers where outflow of the brine-rich waters may be anticipated. These hypersaline subglacial water systems beneath Canadian Arctic ice caps and glaciers may represent robust microbial habitats, and potential analogs for brines that may exist beneath ice masses on planetary

  4. Internationally coordinated glacier monitoring - a timeline since 1894

    Science.gov (United States)

    Nussbaumer, Samuel U.; Armstrong, Richard; Fetterer, Florence; Gärtner-Roer, Isabelle; Hoelzle, Martin; Machguth, Horst; Mölg, Nico; Paul, Frank; Raup, Bruce H.; Zemp, Michael

    2016-04-01

    Changes in glaciers and ice caps provide some of the clearest evidence of climate change, with impacts on sea-level variations, regional hydrological cycles, and natural hazard situations. Therefore, glaciers have been recognized as an Essential Climate Variable (ECV). Internationally coordinated collection and distribution of standardized information about the state and change of glaciers and ice caps was initiated in 1894 and is today organized within the Global Terrestrial Network for Glaciers (GTN-G). GTN-G ensures the continuous development and adaptation of the international strategies to the long-term needs of users in science and policy. A GTN-G Steering Committee coordinates, supports and advices the operational bodies responsible for the international glacier monitoring, which are the World Glacier Monitoring Service (WGMS), the US National Snow and Ice Data Center (NSIDC), and the Global Land Ice Measurements from Space (GLIMS) initiative. In this presentation, we trace the development of the internationally coordinated glacier monitoring since its beginning in the 19th century. Today, several online databases containing a wealth of diverse data types with different levels of detail and global coverage provide fast access to continuously updated information on glacier fluctuation and inventory data. All glacier datasets are made freely available through the respective operational bodies within GTN-G, and can be accessed through the GTN-G Global Glacier Browser (http://www.gtn-g.org/data_browser.html). Glacier inventory data (e.g., digital outlines) are available for about 180,000 glaciers (GLIMS database, RGI - Randolph Glacier Inventory, WGI - World Glacier Inventory). Glacier front variations with about 45,000 entries since the 17th century and about 6,200 glaciological and geodetic mass (volume) change observations dating back to the 19th century are available in the Fluctuations of Glaciers (FoG) database. These datasets reveal clear evidence that

  5. What's new in Rocky Mountain spotted fever?

    Science.gov (United States)

    Chen, Luke F; Sexton, Daniel J

    2008-09-01

    Rocky Mountain spotted fever (RMSF) remains an important illness despite an effective therapy because it is difficult to diagnose and is capable of producing a fatal outcome. The pathogenesis of RMSF remains, in large part, an enigma. However, recent research has helped shed light on this mystery. Importantly, the diagnosis of RMSF must be considered in all febrile patients who have known or possible exposure to ticks, especially if they live in or have traveled to endemic regions during warmer months. Decisions about giving empiric therapy to such patients are difficult and require skill and careful judgement.

  6. Sampling design for long-term regional trends in marine rocky intertidal communities

    Science.gov (United States)

    Irvine, Gail V.; Shelley, Alice

    2013-01-01

    Probability-based designs reduce bias and allow inference of results to the pool of sites from which they were chosen. We developed and tested probability-based designs for monitoring marine rocky intertidal assemblages at Glacier Bay National Park and Preserve (GLBA), Alaska. A multilevel design was used that varied in scale and inference. The levels included aerial surveys, extensive sampling of 25 sites, and more intensive sampling of 6 sites. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope ≤30° was rare. This unexpected finding illustrated one value of probability-based surveys and led to a shift in the target habitat type to include steeper, more mixed rocky habitat. Subsequently, we evaluated the statistical power of different sampling methods and sampling strategies to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles Balanomorpha, the mussel Mytilus trossulus, and the rockweed Fucus distichus subsp. evanescens. There was greatest power to detect trends in Mytilus and lesser power for barnacles and Fucus. Because of its greater power, the extensive, coarse-grained sampling scheme was adopted in subsequent years over the intensive, fine-grained scheme. The sampling attributes that had the largest effects on power included sampling of “vertical” line transects (vs. horizontal line transects or quadrats) and increasing the number of sites. We also evaluated the power of several management-set parameters. Given equal sampling effort, sampling more sites fewer times had greater power. The information gained through intertidal monitoring is likely to be useful in assessing changes due to climate, including ocean acidification; invasive species; trampling effects; and oil spills.

  7. Small Glacier Area Studies: A New Approach for Turkey

    Science.gov (United States)

    Yavasli, Dogukan D.; Tucker, Compton J.

    2012-01-01

    Many regions of Earth have glaciers that have been neglected for study because they are small. We report on a new approach to overcome the problem of studying small glaciers, using Turkey as an example. Prior to our study, no reliable estimates of Turkish glaciers existed because of a lack of systematic mapping, difficulty in using Landsat data collected before 1982, snowpack vs. glacier ice differentiation using existing satellite data and aerial photography, the previous high cost of Landsat images, and a lack of high-resolution imagery of small Turkish glaciers. Since 2008, a large number of area of nine smaller glaciers in Turkey. We also used five Landsat-3 Return Beam Videcon (RBV) 30 m pixel resolution images, all from 1980, for six glaciers. The total area of Turkish glaciers decreased from 23 km2 in the 1970s to 10.1 km2 in 2007-2011. By 2007-2011, six Turkish glaciers disappeared, four were < 0.3 km2, and only three were 1.0 km2 or larger. No trends in precipitation from 1970 to 2006 and cloud cover from 1980 to 2010 were found, while surface temperatures increased, with summer minimum temperatures showing the greatest increase. We conclude that increased surface temperatures during the summer were responsible for the 56% recession of Turkish glaciers from the 1970s to 2006-2011.

  8. Fate of Glaciers in the Tibetan Plateau by 2100

    Science.gov (United States)

    Duan, K.

    2017-12-01

    As the third polar on the Earth, the Tibetan plateau holds more than 40,000 glaciers which have experienced a rapid retreat in recent decades. The variability of equilibrium line altitude (ELA) indicates expansion and wastage of glacier directly. Here we simulated the ELA variability in the Tibetan Plateau based on a full surface energy and mass balance model. The simulation results are agreement with the observations. The ELAs have risen at a rate of 2-8m/a since 1970 throughout the Plateau, especially in the eastern Plateau where the ELAs have risen to or over the top altitude of glacier, indicating the glaciers are accelerating to melting over there. Two glaciers, XD glacier in the center of the Plateau and Qiyi glacier in the Qilian Mountain, are chosen to simulate its future ELA variability in the scenarios of RCP2.6, RCP4.5 and RCP 8.5 given by IPCC. The results show the ELAs will arrive to its maximum in around 2040 in RCP2.6, while the ELAs will be over the top altitude of glaciers in 2035-2045 in RCP4.5 and RCP8.5, suggesting the glaciers in the eastern Plateau will be melting until the disappear of the glaciers by the end of 2100.

  9. Rocky Mountain Research Station: 2012-2013 Annual Report

    Science.gov (United States)

    Cass Cairns

    2013-01-01

    The Rocky Mountain Research Station is one of seven regional units that make up the USDA Forest Service Research and Development organization - the most extensive natural resources research organization in the world. We maintain 12 field laboratories throughout a 12-state territory encompassing the Great Basin, Southwest, Rocky Mountains, and parts of the...

  10. Mass balance of Greenland and the Canadian Ice Caps from combined altimetry and GRACE inversion

    DEFF Research Database (Denmark)

    Forsberg, René; Simonsen, Sebastian Bjerregaard; Sørensen, Louise Sandberg

    The combination of GRACE and altimetry data may yield a high resolution mass balance time series of the Greenlandice sheet, highlighting the varying individual mass loss behaviour of major glaciers. By including the Canadian arctic ice caps in the estimation, a more reliable estimate of the mass...... loss of both Greenlandand the Canadian ice caps may be obtained, minimizing the leakage errors otherwise unavoidable by GRACE. Actually, the absolute value of the Greenlandice sheet mass loss is highly dependent on methods and how the effects of Arctic Canadian ice caps are separated in the GRACE...... loss of the ice caps and ice sheet basins for the period 2003-15. This period shows a marked increase of ice sheet melt, especially in NW and NE Greenland, but also show large variability, with the melt anomaly year of 2012 showing a record mass loss, followed by 2013 with essentially no Greenland mass...

  11. Southwest Greenland's Alpine Glacier History: Recent Glacier Change in the Context of the Holocene Geologic Record

    Science.gov (United States)

    Larocca, L. J.; Axford, Y.; Lasher, G. E.; Lee, C. W.

    2017-12-01

    Due to anthropogenic climate change, the Arctic region is currently undergoing major transformation, and is expected to continue warming much faster than the global average. To put recent and future changes into context, a longer-term understanding of this region's past response to natural climate variability is needed. Given their sensitivity to modest climate change, small alpine glaciers and ice caps on Greenland's coastal margin (beyond the Greenland Ice Sheet) represent ideal features to record climate variability through the Holocene. Here we investigate the Holocene history of a small ( 160 square km) ice cap and adjacent alpine glaciers, located in southwest Greenland approximately 50 km south of Nuuk. We employ measurements on sediment cores from a glacier-fed lake in combination with geospatial analysis of satellite images spanning the past several decades. Sedimentary indicators of sediment source and thus glacial activity, including organic matter abundance, inferred chlorophyll-a content, sediment major element abundances, grain size, and magnetic susceptibility are presented from cores collected from a distal glacier-fed lake (informally referred to here as Per's Lake) in the summer of 2015. These parameters reflect changes in the amount and character of inorganic detrital input into the lake, which may be linked to the size of the upstream glaciers and ice cap and allow us to reconstruct their status through the Holocene. Additionally, we present a complementary record of recent changes in Equilibrium Line Altitude (ELA) for the upstream alpine glaciers. Modern ELAs are inferred using the accumulation area ratio (AAR) method in ArcGIS via Landsat and Worldview-2 satellite imagery, along with elevation data obtained from digital elevation models (DEMs). Paleo-ELAs are inferred from the positions of moraines and trim lines marking the glaciers' most recent expanded state, which we attribute to the Little Ice Age (LIA). This approach will allow us to

  12. Comparison of Glaciological and Gravimetric Glacier Mass Balance Measurements of Taku and Lemon Creek Glaciers, Southeast Alaska

    Science.gov (United States)

    Vogler, K.; McNeil, C.; Bond, M.; Getraer, B.; Huxley-Reicher, B.; McNamara, G.; Reinhardt-Ertman, T.; Silverwood, J.; Kienholz, C.; Beedle, M. J.

    2017-12-01

    Glacier-wide annual mass balances (Ba) have been calculated for Taku (726 km2) and Lemon Creek glaciers (10.2 km2) since 1946 and 1953 respectively. These are the longest mass balance records in North America, and the only Ba time-series available for Southeast Alaska, making them particularly valuable for the global glacier mass balance monitoring network. We compared Ba time-series from Taku and Lemon Creek glaciers to Gravity Recovery and Climate Experiment (GRACE) mascon solutions (1352 and 1353) during the 2004-2015 period to assess how well these gravimetric solutions reflect individual glaciological records. Lemon Creek Glacier is a challenging candidate for this comparison because it is small compared to the 12,100 km2 GRACE mascon solutions. Taku Glacier is equally challenging because its mass balance is stable compared to the negative balances dominating its neighboring glaciers. Challenges notwithstanding, a high correlation between the glaciological and gravimetrically-derived Ba for Taku and Lemon Creek glaciers encourage future use of GRACE to measure glacier mass balance. Additionally, we employed high frequency ground penetrating radar (GPR) to measure the variability of accumulation around glaciological sites to assess uncertainty in our glaciological measurements, and the resulting impact to Ba. Finally, we synthesize this comparison of glaciological and gravimetric mass balance solutions with a discussion of potential sources of error in both methods and their combined utility for measuring regional glacier change during the 21st century.

  13. Disposal of Rocky Flats residues as waste

    International Nuclear Information System (INIS)

    Dustin, D.F.; Sendelweck, V.S.

    1993-01-01

    Work is underway at the Rocky Flats Plant to evaluate alternatives for the removal of a large inventory of plutonium-contaminated residues from the plant. One alternative under consideration is to package the residues as transuranic wastes for ultimate shipment to the Waste Isolation Pilot Plant. Current waste acceptance criteria and transportation regulations require that approximately 1000 cubic yards of residues be repackaged to produce over 20,000 cubic yards of WIPP certified waste. The major regulatory drivers leading to this increase in waste volume are the fissile gram equivalent, surface radiation dose rate, and thermal power limits. In the interest of waste minimization, analyses have been conducted to determine, for each residue type, the controlling criterion leading to the volume increase, the impact of relaxing that criterion on subsequent waste volume, and the means by which rules changes may be implemented. The results of this study have identified the most appropriate changes to be proposed in regulatory requirements in order to minimize the costs of disposing of Rocky Flats residues as transuranic wastes

  14. Risk, media, and stigma at Rocky Flats

    International Nuclear Information System (INIS)

    Flynn, J.; Peters, E.; Mertz, C.K.; Slovic, P.

    1998-01-01

    Public responses to nuclear technologies are often strongly negative. Events, such as accidents or evidence of unsafe conditions at nuclear facilities, receive extensive and dramatic coverage by the news media. These news stories affect public perceptions of nuclear risks and the geographic areas near nuclear facilities. One result of these perceptions, avoidance behavior, is a form of technological stigma that leads to losses in property values near nuclear facilities. The social amplification of risk is a conceptual framework that attempts to explain how stigma is created through media transmission of information about hazardous places and public perceptions and decisions. This paper examines stigma associated with the US Department of energy's Rocky Flats facility, a major production plant in the nation's nuclear weapons complex, located near Denver, Colorado. This study, based upon newspaper analyses and a survey of Denver area residents, finds that the social amplification theory provides a reasonable framework for understanding the events and public responses that took place in regard to Rocky Flats during a 6-year period, beginning with an FBI raid of the facility in 1989

  15. Canadian competitive advantage

    International Nuclear Information System (INIS)

    Wills, J.

    1997-01-01

    The evolution of the Canadian petrochemical industry was outlined, emphasizing the proximity to feedstocks as the principal advantage enjoyed by the industry over its international competitors. Annual sales statistics for 1995 were provided. Key players in the Canadian petrochemical industry (Nova, Dow, DuPont, Methanex, Esso, Union Carbide, Shell and Celanese), their share of the market and key products were noted. Manufacturing facilities are located primarily in Alberta, southern Ontario and Quebec. The feedstock supply infrastructure, historical and alternative ethane pricing in Canada and the US, the North American market for petrochemicals, the competitiveness of the industry, tax competitiveness among Canadian provinces and the US, the Canada - US unit labour cost ratio, ethylene facility construction costs in Canada relative to the US Gulf Coast, and projected 1997 financial requirements were reviewed. 19 figs

  16. Outlook for Canadian refining

    International Nuclear Information System (INIS)

    Boje, G.

    1998-01-01

    The petroleum supply and demand balance was discussed and a comparison between Canadian and U.S. refineries was provided. The impact of changing product specifications on the petroleum industry was also discussed. The major changes include sulphur reductions in gasoline, benzene and MMT additives. These changes have been made in an effort to satisfy environmental needs. Geographic margin variations in refineries between east and west were reviewed. An overview of findings from the Solomon Refining Study of Canadian and American refineries, which has been very complimentary of the Canadian refining industry, was provided. From this writer's point of view refinery utilization has improved but there is a threat from increasing efficiency of US competitors. Environmental issues will continue to impact upon the industry and while the chances for making economic returns on investment are good for the years ahead, it will be a challenge to maintain profitability

  17. Glaciers and ice caps outside Greenland

    Science.gov (United States)

    Sharp, Marin; Wolken, G.; Burgess, D.; Cogley, J.G.; Copland, L.; Thomson, L.; Arendt, A.; Wouters, B.; Kohler, J.; Andreassen, L.M.; O'Neel, Shad; Pelto, M.

    2015-01-01

    Mountain glaciers and ice caps cover an area of over 400 000 km2 in the Arctic, and are a major influence on global sea level (Gardner et al. 2011, 2013; Jacob et al. 2012). They gain mass by snow accumulation and lose mass by meltwater runoff. Where they terminate in water (ocean or lake), they also lose mass by iceberg calving. The climatic mass balance (Bclim, the difference between annual snow accumulation and annual meltwater runoff) is a widely used index of how glaciers respond to climate variability and change. The total mass balance (ΔM) is defined as the difference between annual snow accumulation and annual mass losses (by iceberg calving plus runoff).

  18. On tritium content in the Abramov glacier layers

    International Nuclear Information System (INIS)

    Voronskaya, G.N.; Nikolishin, I.Ya.; Romanov, V.V.

    1976-01-01

    Using the common pattern of the analysis of tritium in natural waters its concentration was determined in sampeles of annual layers of the Abramov glacier (Pamir-Altai) at the height of 4500 m above the sea level for 1927-1972. The tritium activity was measured with the help of the liquid scintillation spectrometer with the 10 per cent accuracy. The nature of the obtained curve of the distribution of tritium in the Abramov glacier annual layers was close to its, distribution in glaciers of Greenland, in the Fedchenko glacier and in the precipitation of Teheran. The absolute values of tritium concentrations in the Pamir glaciers are significantly lower than in glaciers of Greenlad. The maximum of tritium concentrations is observed in samples which correspond to 1963, its value approximating to 800 tritium units

  19. An Analysis of Mass Balance of Chilean Glaciers

    Science.gov (United States)

    Ambinakudige, S.; Tetteh, L.

    2013-12-01

    Glaciers in Chile range from very small glacierets found on the isolated volcanoes of northern Chile to the 13,000 sq.km Southern Patagonian Ice Field. Regular monitoring of these glaciers is very important as they are considered as sensitive indicators of climate change. Millions of people's lives are dependent on these glaciers for fresh water and irrigation purpose. In this study, mass balances of several Chilean glaciers were estimated using Aster satellite images between 2007 and 2012. Highly accurate DEMs were created with supplementary information from IceSat data. The result indicated a negative mass balance for many glaciers indicating the need for further monitoring of glaciers in the Andes.

  20. Seasonal dynamic thinning at Helheim Glacier

    DEFF Research Database (Denmark)

    Bevan, Suzanne L.; Luckman, Adrian; Khan, Shfaqat Abbas

    2015-01-01

    of 671±70kgm-3 and calculate that total water equivalent volume loss from the active part of the glacier (surface flow speeds >1 m day-1) ranges from 0.5 km3 in 2011 to 1.6 km3 in 2013. A rough ice-flux divergence analysis shows that at lower elevations (... the time series, that melt-induced acceleration is most likely the main driver of the seasonal dynamic thinning, as opposed to changes triggered by retreat....

  1. Canadian Irradiation Centre

    International Nuclear Information System (INIS)

    1987-05-01

    The Canadian Irradiation Centre is a non-profit cooperative project between Atomic Energy of Canada Limited, Radiochemical Company and Universite du Quebec, Institut Armand-Frappier, Centre for Applied Research in Food Science. The Centre's objectives are to develop, demonstrate and promote Canada's radiation processing technology and its applications by conducting applied research; training technical, professional and scientific personnel; educating industry and government; demonstrating operational and scientific procedures; developing processing procedures and standards, and performing product and market acceptance trials. This pamphlet outlines the history of radoation technology and the services offered by the Canadian Irradiation Centre

  2. Plant Functional Traits Are More Consistent Than Plant Species on Periglacial Patterned Ground in the Rocky Mountains of Montana

    Science.gov (United States)

    Apple, M. E.; Ricketts, M. K.; Gallagher, J. H. R.

    2017-12-01

    Periglacial patterned ground exists as stripes and hexagons near glaciers and snowfields, some of which are former glaciers. The patterns are accentuated by profound differences in plant cover between the sloping surfaces, generally perceived as green, and the flat treads, generally perceived as brown but which are not devoid of plant life. On four sites in the Rocky Mountains of Montana we detected strong similarities in plant functional traits on the sloping surfaces of striped and hexagonal periglacial patterned ground. On Mt. Keokirk in the Pioneer Mountains, Kinnickinnick, Arctostaphylos uva-ursi, dominates narrow green stripes. On Goat Flat in the Pintler Mountains, Mountain Avens, Dryas octopetala, dominates the side walls of hexagonally patterned ground and narrow green stripes. At Glacier National Park, D. octopetala and the Arctic Willow, Salix arctica, co-dominate the green risers of widely-spaced striped periglacial patterned system at Siyeh Pass, while D. octopetala, S. arctica, and the Mountain Heather, Phyllodoce glanduliflora, co-dominate the green risers of the widely-spaced stripes of Piegan Pass. All four of these dictotyledonous angiosperm species are adventitiously-rooted dwarf shrubs with simple leaves. Of these, P. glanduliflora, A. uva-ursi and D. octopetala are evergreen. D. octopetala is symbiotic with N-fixing Frankia sp. All are mycorrhizal, although D. octopetala and S. arctica are ectomycorrhizal and P. glanduliflora and A. uva-ursi have ericaceous mycorrhizae. In contrast, dwarf shrubs are scarce on flat treads and within hexagons, which are chiefly inhabited by herbaceous, taprooted or rhizomatous, VAM angiosperms. As the green stripes and hexagon walls have greater plant cover, they likely have greater organic material due to leaf buildup and root turnover, anchor themselves and the soil with adventitious roots, their clonality suggests long lives, and N-fixing influences N dynamics of the periglacial patterned ground.

  3. Numerical modeling of the Snowmass Creek paleoglacier, Colorado, and climate in the Rocky Mountains during the Bull Lake glaciation (MIS 6)

    Energy Technology Data Exchange (ETDEWEB)

    Eric M. Leonard; Mitchell A. Plummer; Paul E. Carrara

    2014-04-01

    Well-preserved moraines from the penultimate, or Bull Lake, glaciation of Snowmass Creek Valley in the Elk Range of Colorado present an opportunity to examine the character of the high-altitude climate in the Rocky Mountains during Marine Oxygen Isotope Stage 6. This study employs a 2-D coupled mass/energy balance and flow model to assess the magnitudes of temperature and precipitation change that could have sustained the glacier in mass-balance equilibrium at its maximum extent during the Bull Lake glaciation. Variable substrate effects on glacier flow and ice thickness make the modeling somewhat more complex than in geologically simpler settings. Model results indicate that a temperature depression of about 6.7°C compared with the present (1971–2000 AD) would have been necessary to sustain the Snowmass Creek glacier in mass-balance equilibrium during the Bull Lake glaciation, assuming no change in precipitation amount or seasonality. A 50% increase or decrease from modern precipitation would have been coupled with 5.2°C and 9.1°C Bull Lake temperature depressions respectively. Uncertainty in these modeled temperature depressions is about 1°C.

  4. Acceleration of Humboldt glacier, north Greenland

    Science.gov (United States)

    Jeong, S.; Howat, I.; Noh, M. J.; King, M. D.

    2017-12-01

    Here we report on recent abrupt acceleration on the flow speed of Humboldt Glacier (HG) in northern Greenland. The mean annual discharge of this glacier in 2000 was estimated as 8.4Gt/a, placing it among the largest outlet glacier draining the northern coast (Enderlin et al., 2014). Using a combination of remote sensing datasets, we find that following a slight slowing before 2010, HG suddenly sped up by a factor of three between 2012 and 2013, maintaining that increased speed through 2016. Speedup was accompanied by up to 10 m of thinning near the terminus and followed slower, longer-term thinning and retreat. Here we assess possible causes for the speedup, potential for continued acceleration and implication to ice sheet mass balance. ReferenceEnderlin, E. M., I. M. Howat, S. Jeong, M.-J. Noh, J. H. van Angelen, and M. R. van den Broeke (2014), An improved mass budget for the Greenland ice sheet, Geophys. Res. Lett., 41, 866-872, doi:10.1002/2013GL059010.

  5. The retreat of mountain glaciers: what can satellites tell us?

    International Nuclear Information System (INIS)

    Berthier, E.

    2008-01-01

    Mountain glaciers are one of the best indicators of climate change and their rapid wastage make them a strong contributor to sea level rise. The estimated 160,000 mountain glaciers are spread all around the globe and remain difficult to access. Consequently, only a limited number (about 50 glaciers) are regularly monitored in the field. Today, high resolution satellite optical images are combined to some advanced methodologies to survey their fast and alarming evolution. (author)

  6. Global-scale hydrological response to future glacier mass loss

    Science.gov (United States)

    Huss, Matthias; Hock, Regine

    2018-01-01

    Worldwide glacier retreat and associated future runoff changes raise major concerns over the sustainability of global water resources1-4, but global-scale assessments of glacier decline and the resulting hydrological consequences are scarce5,6. Here we compute global glacier runoff changes for 56 large-scale glacierized drainage basins to 2100 and analyse the glacial impact on streamflow. In roughly half of the investigated basins, the modelled annual glacier runoff continues to rise until a maximum (`peak water') is reached, beyond which runoff steadily declines. In the remaining basins, this tipping point has already been passed. Peak water occurs later in basins with larger glaciers and higher ice-cover fractions. Typically, future glacier runoff increases in early summer but decreases in late summer. Although most of the 56 basins have less than 2% ice coverage, by 2100 one-third of them might experience runoff decreases greater than 10% due to glacier mass loss in at least one month of the melt season, with the largest reductions in central Asia and the Andes. We conclude that, even in large-scale basins with minimal ice-cover fraction, the downstream hydrological effects of continued glacier wastage can be substantial, but the magnitudes vary greatly among basins and throughout the melt season.

  7. Improving estimation of glacier volume change: a GLIMS case study of Bering Glacier System, Alaska

    Directory of Open Access Journals (Sweden)

    M. J. Beedle

    2008-04-01

    Full Text Available The Global Land Ice Measurements from Space (GLIMS project has developed tools and methods that can be employed by analysts to create accurate glacier outlines. To illustrate the importance of accurate glacier outlines and the effectiveness of GLIMS standards we conducted a case study on Bering Glacier System (BGS, Alaska. BGS is a complex glacier system aggregated from multiple drainage basins, numerous tributaries, and many accumulation areas. Published measurements of BGS surface area vary from 1740 to 6200 km2, depending on how the boundaries of this system have been defined. Utilizing GLIMS tools and standards we have completed a new outline (3630 km2 and analysis of the area-altitude distribution (hypsometry of BGS using Landsat images from 2000 and 2001 and a US Geological Survey 15-min digital elevation model. We compared this new hypsometry with three different hypsometries to illustrate the errors that result from the widely varying estimates of BGS extent. The use of different BGS hypsometries results in highly variable measures of volume change and net balance (bn. Applying a simple hypsometry-dependent mass-balance model to different hypsometries results in a bn rate range of −1.0 to −3.1 m a−1 water equivalent (W.E., a volume change range of −3.8 to −6.7 km3 a−1 W.E., and a near doubling in contributions to sea level equivalent, 0.011 mm a−1 to 0.019 mm a−1. Current inaccuracies in glacier outlines hinder our ability to correctly quantify glacier change. Understanding of glacier extents can become comprehensive and accurate. Such accuracy is possible with the increasing volume of satellite imagery of glacierized regions, recent advances in tools and standards, and dedication to this important task.

  8. Human Activity Differentially Redistributes Large Mammals in the Canadian Rockies National Parks

    Directory of Open Access Journals (Sweden)

    James Kimo. Rogala

    2011-09-01

    Full Text Available National parks are important for conservation of species such as wolves (Canis lupus and elk (Cervus canadensis. However, topography, vegetation conditions, and anthropogenic infrastructure within parks may limit available habitat. Human activity on trails and roads may lead to indirect habitat loss, further limiting available habitat. Predators and prey may respond differentially to human activity, potentially disrupting ecological processes. However, research on such impacts to wildlife is incomplete, especially at fine spatial and temporal scales. Our research investigated the relationship between wolf and elk distribution and human activity using fine-scale Global Positioning System (GPS wildlife telemetry locations and hourly human activity measures on trails and roads in Banff, Kootenay, and Yoho National Parks, Canada. We observed a complex interaction between the distance animals were located from trails and human activity level resulting in species adopting both mutual avoidance and differential response behaviors. In areas < 50 m from trails human activity led to a mutual avoidance response by both wolves and elk. In areas 50 - 400 m from trails low levels of human activity led to differential responses; wolves avoided these areas, whereas elk appeared to use these areas as a predation refugia. These differential impacts on elk and wolves may have important implications for trophic dynamics. As human activity increased above two people/hour, areas 50 - 400 m from trails were mutually avoided by both species, resulting in the indirect loss of important montane habitat. If park managers are concerned with human impacts on wolves and elk, or on these species' trophic interactions with other species, they can monitor locations near trails and roads and consider hourly changes of human activity levels in areas important to wildlife.

  9. Re-measurement of whitebark pine infection and mortality in the Canadian Rockies

    Science.gov (United States)

    Cyndi M. Smith; Brenda Shepherd; Cameron Gillies; Jon Stuart-Smith

    2011-01-01

    Whitebark pine (Pinus albicaulis) populations are under threat across the species' range from white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus ponderosae), fire exclusion and climate change (Tomback and Achuff 2010). Loss of whitebark pine is predicted to have cascading effects on the following ecological services: provision of...

  10. Deep groundwater circulation and associated methane leakage in the northern Canadian Rocky Mountains

    International Nuclear Information System (INIS)

    Grasby, S.E.; Ferguson, G.; Brady, A.; Sharp, C.; Dunfield, P.; McMechan, M.

    2016-01-01

    Concern over potential impact of shale gas development on shallow groundwater systems requires greater understanding of crustal scale fluid movement. We examined natural deeply circulating groundwater systems in northeastern British Columbia adjacent to a region of shale gas development, in order to elucidate origin of waters, depths of circulation, and controls on fluid flow. These systems are expressed as thermal springs that occur in the deformed sedimentary rocks of the Liard Basin. Stable isotope data from these springs show that they originate as meteoric water. Although there are no thermal anomalies in the region, outlet temperatures range from 30 to 56 °C, reflecting depth of circulation. Based on aqueous geothermometry and geothermal gradients, circulation depths up to 3.8 km are estimated, demonstrating connection of deep groundwater systems to the surface. Springs are also characterised by leakage of thermogenic gas from deep strata that is partly attenuated by methanotrophic microbial communities in the spring waters. Springs are restricted to anomalous structural features, cross cutting faults, and crests of fault-cored anticlines. On a regional scale they are aligned with the major tectonic features of the Liard Line and Larsen Fault. This suggests that while connection of surface to deep reservoirs is possible, it is rare and restricted to highly deformed geologic units that produce permeable pathways from depth through otherwise thick intervening shale units. Results allow a better understanding of potential for communication between deep shale gas units and shallow aquifer systems. - Highlights: • Deep groundwater systems were studied near active shale gas development. • Natural fracture systems allow circulation of meteoric water to depths of 3.8 km. • Deep circulation systems occur, but are rare in even highly deformed rocks.

  11. Canadian heavy water production

    International Nuclear Information System (INIS)

    Dahlinger, A.; Lockerby, W.E.; Rae, H.K.

    1977-05-01

    The paper reviews Canadian experience in the production of heavy water, presents a long-term supply projection, relates this projection to the anticipated long-term electrical energy demand, and highlights principal areas for further improvement that form the bulk of our research and development program on heavy water processes

  12. Canadian petroleum industry review

    International Nuclear Information System (INIS)

    Feick, R. M.

    1997-01-01

    A wide ranging discussion about the factors that have influenced oil and natural gas prices, the differences of the Canadian market from international markets, the differences between eastern and western Canadian markets, and shareholders' perspectives on recent commodity price developments was presented. Developments in the OPEC countries were reviewed, noting that current OPEC production of 25 mmbbls is about 60 per cent higher than it was in 1985. It is expected that OPEC countries will continue to expand capacity to meet expected demand growth and the continuing need created by the UN embargo on Iraqi oil sales. Demand for natural gas is also likely to continue to rise especially in view of the deregulation of the electricity industry where natural gas may well become the favored fuel for incremental thermal generation capacity. Prices of both crude oil and natural gas are expected to hold owing to unusually low storage levels of both fuels. The inadequacy of infrastructure, particularly pipeline capacity as a key factor in the Canadian market was noted, along with the dynamic that will emerge in the next several years that may have potential consequences for Canadian production - namely the reversal of the Sarnia to Montreal pipeline. With regard to shareholders' expectations the main issues are (1) whether international markets reach back to the wellhead, hence the producer's positioning with respect to transportation capacity and contract portfolios, and (2) whether the proceeds from increased prices are invested in projects that are yielding more than the cost of capital. 28 figs

  13. Canadian gas resource

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    Canadian exports of gas to the United States are a critical component of EMF-9 (North American Gas Supplies). However, it has been noted that there are differences between US expectations for imports and Canadian forecasts of export supply capacity. Recent studies by the National Petroleum Council (NPC) and the US Department of Energy (DOE) indicate that 1.8 to 2.4 Tcf of imports may be required in the mid to late 1990's; A recent study by Canada's National Energy Board (NEB) indicates that the conventional resource base may not be able to provide continued gas exports to the US after the mid 1990's and that frontier sources would need to be developed to meet US expectations. The discrepancies between US expectations and Canadian estimates of capacity are of great concern to US policymakers because they call into question the availability of secure supplies of natural gas and suggest that the cost of imports (if available) will be high. By implication, if shortages are to be averted, massive investment may be required to bring these higher cost sources to market. Since the long-term supply picture will be determined by the underlying resource base, EMF-9 participants have been asked to provide estimates of critical components of the Canadian resource base. This paper provides a summary of ICF-Lewin's recent investigation of both the Conventional and Tight Gas resource in Canada's Western Sedimentary Basin, which includes both quantitative estimates and a brief sketch of the analysis methodology

  14. Canadian petroleum industry

    Energy Technology Data Exchange (ETDEWEB)

    Dagher, J.H.

    1969-12-01

    This study covers the following Canadian petroleum industry categories: (1) a brief history; (2) the demand for Alberta crude; (3) U.S. oil policies; (4) overseas exploration; (5) the national oil policy; (6) the Montreal pipeline and its targets; (7) a continental oil policy; and (8) the impact of Arctic reserves. It is noted that large potential benefits will improve from the Manhattan navigating the Northwest Passage. Without prejudging the analysis now applied to the information gathered on this voyage, the Manhattan has greatly contributed to the solution of the problem of access to the Arctic islands. The picture for natural gas is less fraught with uncertainties. Unlike oil, where domestic and international considerations may weigh in U.S. policy decision, Canadian natural gas is likely to be allowed to enjoy its full economic potential in bridging the foreseeable U.S. supply gap and, inasmuch as this potential is ultimately tied with that for crude oil markets, the anticipated U.S. needs for Canadian natural gas may be expected to enhance U.S. interest in the overall well-being of the Canadian petroleum industry.

  15. Canadian hydrogen safety program

    International Nuclear Information System (INIS)

    MacIntyre, I.; Tchouvelev, A.V.; Hay, D.R.; Wong, J.; Grant, J.; Benard, P.

    2007-01-01

    The Canadian hydrogen safety program (CHSP) is a project initiative of the Codes and Standards Working Group of the Canadian transportation fuel cell alliance (CTFCA) that represents industry, academia, government, and regulators. The Program rationale, structure and contents contribute to acceptance of the products, services and systems of the Canadian Hydrogen Industry into the Canadian hydrogen stakeholder community. It facilitates trade through fair insurance policies and rates, effective and efficient regulatory approval procedures and accommodation of the interests of the general public. The Program integrates a consistent quantitative risk assessment methodology with experimental (destructive and non-destructive) failure rates and consequence-of-release data for key hydrogen components and systems into risk assessment of commercial application scenarios. Its current and past six projects include Intelligent Virtual Hydrogen Filling Station (IVHFS), Hydrogen clearance distances, comparative quantitative risk comparison of hydrogen and compressed natural gas (CNG) refuelling options; computational fluid dynamics (CFD) modeling validation, calibration and enhancement; enhancement of frequency and probability analysis, and Consequence analysis of key component failures of hydrogen systems; and fuel cell oxidant outlet hydrogen sensor project. The Program projects are tightly linked with the content of the International Energy Agency (IEA) Task 19 Hydrogen Safety. (author)

  16. Canadian Nuclear Association

    International Nuclear Information System (INIS)

    Reid, John

    1992-01-01

    It is the view of the Canadian Nuclear Association that continuing creation of economic wealth is vital to sustainable development. A plentiful supply of cheap energy is essential. Nuclear energy provides the cleanest source of bulk energy generation essential to any path of sustainable development

  17. Structure and changing dynamics of a polythermal valley glacier on a centennial timescale - Midre Lovenbreen, Svalbard

    DEFF Research Database (Denmark)

    Hambrey, M. J.; Murray, T.; Glasser, N. F.

    2005-01-01

    structural glaciology, polythermal glacier, Svalbard, ground-penetrating radar, numerical modeling......structural glaciology, polythermal glacier, Svalbard, ground-penetrating radar, numerical modeling...

  18. NEPA/CERCLA integration at Rocky Flats

    International Nuclear Information System (INIS)

    Schassburger, R.J.

    1991-01-01

    Integration of two laws, the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the National Environmental Policy Act (NEPA) was mandated by the US Department of Energy (DOE) with issuance of DOE Order 5400.4 in October 6, 1989. NEPA documentation is required for all federal actions to thereby consider the impacts of such actions prior to the action taking place. On the other hand, CERCLA actions taken by the US Environmental Protection Agency (EPA) at non-federal and federal sites do not normally take NEPA into consideration, although it is not exempted at federal sites. EPA claims that CERCLA is functionally equivalent to N-EPA and therefore NEPA is not required. Although EPA maintains the functional equivalency of the two laws and formerly resisted to recognize NEPA even in Inter-Agency Agreements (IAGs), Rocky Flats has been integrating the two laws within documents to avoid duplication of information and effort

  19. Rocky Mountain spotted fever in Argentina.

    Science.gov (United States)

    Paddock, Christopher D; Fernandez, Susana; Echenique, Gustavo A; Sumner, John W; Reeves, Will K; Zaki, Sherif R; Remondegui, Carlos E

    2008-04-01

    We describe the first molecular confirmation of Rickettsia rickettsii, the cause of Rocky Mountain spotted fever (RMSF), from a tick vector, Amblyomma cajennense, and from a cluster of fatal spotted fever cases in Argentina. Questing A. cajennense ticks were collected at or near sites of presumed or confirmed cases of spotted fever rickettsiosis in Jujuy Province and evaluated by polymerase chain reaction assays for spotted fever group rickettsiae. DNA of R. rickettsii was amplified from a pool of A. cajennense ticks and from tissues of one of four patients who died during 2003-2004 after illnesses characterized by high fever, severe headache, myalgias, and petechial rash. The diagnosis of spotted fever rickettsiosis was confirmed in the other patients by indirect immunofluorescence antibody and immunohistochemical staining techniques. These findings show the existence of RMSF in Argentina and emphasize the need for clinicians throughout the Americas to consider RMSF in patients with febrile rash illnesses.

  20. Present dynamics and future prognosis of a slowly surging glacier

    Directory of Open Access Journals (Sweden)

    G. E. Flowers

    2011-03-01

    Full Text Available Glacier surges are a well-known example of an internal dynamic oscillation whose occurrence is not a direct response to the external climate forcing, but whose character (i.e. period, amplitude, mechanism may depend on the glacier's environmental or climate setting. We examine the dynamics of a small (∼5 km2 valley glacier in Yukon, Canada, where two previous surges have been photographically documented and an unusually slow surge is currently underway. To characterize the dynamics of the present surge, and to speculate on the future of this glacier, we employ a higher-order flowband model of ice dynamics with a regularized Coulomb-friction sliding law in both diagnostic and prognostic simulations. Diagnostic (force balance calculations capture the measured ice-surface velocity profile only when non-zero basal water pressures are prescribed over the central region of the glacier, coincident with where evidence of the surge has been identified. This leads to sliding accounting for 50–100% of the total surface motion in this region. Prognostic simulations, where the glacier geometry evolves in response to a prescribed surface mass balance, reveal a significant role played by a bedrock ridge beneath the current equilibrium line of the glacier. Ice thickening occurs above the ridge in our simulations, until the net mass balance reaches sufficiently negative values. We suggest that the bedrock ridge may contribute to the propensity for surges in this glacier by promoting the development of the reservoir area during quiescence, and may permit surges to occur under more negative balance conditions than would otherwise be possible. Collectively, these results corroborate our interpretation of the current glacier flow regime as indicative of a slow surge that has been ongoing for some time, and support a relationship between surge incidence or character and the net mass balance. Our results also highlight the importance of glacier bed

  1. Climate Change and Glacier Retreat: Scientific Fact and Artistic Opportunity

    Science.gov (United States)

    Fagre, D. B.

    2008-12-01

    Mountain glaciers continue to retreat rapidly over most of the globe. In North America, at Glacier National Park, Montana, recent research results from Sperry Glacier (2005-2007) indicate negative mass balances are now 3-4 times greater than in the 1950s. A geospatial model of glacier retreat in the Blackfoot-Jackson basin suggested all glaciers would be gone by 2030 but has proved too conservative. Accelerated glacier shrinkage since the model was developed has mirrored an increase in actual annual temperature that is almost twice the rate used in the model. The glaciers in Glacier National Park are likely to be gone well before 2030. A variety of media, curricula, and educational strategies have been employed to communicate the disappearance of the glaciers as a consequence of global warming. These have included everything from print media and television coverage to podcasts and wayside exhibits along roads in the park. However, a new thrust is to partner with artists to communicate climate change issues to new audiences and through different channels. A scientist-artist retreat was convened to explore the tension between keeping artistic products grounded in factually-based reality while providing for freedom to express artistic creativity. Individual artists and scientists have worked to create aesthetic and emotional images, using painting, poetry, music and photography, to convey core messages from research on mountain ecosystems. Finally, a traveling art exhibit was developed to highlight the photography that systematically documents glacier change through time. The aim was to select photographs that provide the most compelling visual experience for an art-oriented viewer and also accurately reflect the research on glacier retreat. The exhibit opens on January 11, 2009

  2. Mountains, glaciers, and mines—The geological story of the Blue River valley, Colorado, and its surrounding mountains

    Science.gov (United States)

    Kellogg, Karl; Bryant, Bruce; Shroba, Ralph R.

    2016-02-10

    This report describes, in a nontechnical style, the geologic history and mining activity in the Blue River region of Colorado, which includes all of Summit County. The geologic story begins with the formation of ancient basement rocks, as old as about 1700 million years, and continues with the deposition of sedimentary rocks on a vast erosional surface beginning in the Cambrian Period (about 530 million years ago). This deposition was interrupted by uplift of the Ancestral Rocky Mountains during the late Paleozoic Era (about 300 million years ago). The present Rocky Mountains began to rise at the close of the Mesozoic Era (about 65 million years ago). A few tens of millions years ago, rifting began to form the Blue River valley; a major fault along the east side of the Gore Range dropped the east side down, forming the present valley. The valley once was filled by sediments and volcanic rocks that are now largely eroded. During the last few hundred-thousand years, at least two periods of glaciation sculpted the mountains bordering the valley and glaciers extended down the Blue River valley as far south as present Dillon Reservoir. Discovery of deposits of gold, silver, copper, and zinc in the late 1800s, particularly in the Breckenridge region, brought an influx of early settlers. The world-class molybdenum deposit at Climax, mined since the First World War, reopened in 2012 after a period of closure.

  3. Simulation of historic glacier variations with a simple climate-glacier model

    NARCIS (Netherlands)

    Oerlemans, J.

    1988-01-01

    Glacier variations during the last few centuries have shown a marked coherence over the globe. Characteristic features are the maximum stand somewhere in the middle of the nineteenth century, and the steady retreat afterwards (with some minor interrruptions depending on the particular region).

  4. Tracer-based identification of rock glacier thawing in a glacierized Alpine catchment

    Science.gov (United States)

    Engel, Michael; Penna, Daniele; Tirler, Werner; Comiti, Francesco

    2017-04-01

    Current warming in high mountains leads to increased melting of snow, glacier ice and permafrost. In particular rock glaciers, as a creeping form of mountain permafrost, may release contaminants such as heavy metals into the stream during intense melting periods in summer. This may have strong impacts on both water quantity and quality of fresh water resources but might also harm the aquatic fauna in mountain regions. In this context, the present study used stable isotopes of water and electrical conductivity (EC) combined with trace, major and minor elements to identify the influence of permafrost thawing on the water quality in the glacierized Solda catchment (130 km2) in South Tyrol (Italy). We carried out a monthly sampling of two springs fed by an active rock glacier at about 2600 m a.s.l. from July to October 2015. Furthermore, we took monthly water samples from different stream sections of the Solda River (1110 to m a.s.l.) from March to November 2015. Meteorological data were measured by an Automatic Weather Station at 2825 m a.s.l. of the Hydrographic Office (Autonomous Province of Bozen-Bolzano). First results show that water from the rock glacier springs and stream water fell along the global meteoric water line. Spring water was slightly more variable in isotopic ratio (δ2H: -91 to - 105 ) and less variable in dissolved solutes (EC: 380 to 611 μS/cm) than stream water (δ2H: -96 to - 107 ‰ and EC: 212 to 927 μS/cm). Both spring water and stream water showed a pronounced drop in EC during July and August, very likely induced by increased melt water dilution. In both water types, element concentrations of Ca and Mg were highest (up to 160 and 20 mg/l, respectively). In September, spring water showed higher concentrations in Cu, As, and Pb than stream water, indicating that these elements partly exceeded the concentration limit for drinking water. These observations highlight the important control, which rock glacier thawing may have on water quality

  5. MEASURING SURFACE DEFORMATION IN GLACIER RETREATED AREAS BASED ON PS-INSAR – GELADANDONG GLACIER AS A CASE STUDY

    Directory of Open Access Journals (Sweden)

    B. Mohamadi

    2018-04-01

    Full Text Available Glaciers are retreating in many parts of the world as a result of global warming. Many researchers consider Qinghai-Tibetan Plateau as a reference for climate change by measuring glaciers retreat on the plateau. This retreat resulted in some topographic changes in retreated areas, and in some cases can lead to geohazards as landslides, and rock avalanches, which is known in glacier retreated areas as paraglacial slope failure (PSF. In this study, Geladandong biggest and main glacier mass was selected to estimate surface deformation on its glacier retreated areas and define potential future PSF based on PS-InSAR technique. 56 ascending and 49 descending images were used to fulfill this aim. Geladandong glacier retreated areas were defined based on the maximum extent of the glacier in the little ice age. Results revealed a general uplift in the glacier retreated areas with velocity less than 5mm/year. Obvious surface motion was revealed in seven parts surround glacier retreated areas with high relative velocity reached ±60mm/year in some parts. Four parts were considered as PSF potential motion, and two of them showed potential damage for the main road in the study area in case of rock avalanche into recent glacier lakes that could result in glacier lake outburst flooding heading directly to the road. Finally, further analysis and field investigations are needed to define the main reasons for different types of deformation and estimate future risks of these types of surface motion in the Qinghai-Tibetan Plateau.

  6. Tidal bending of glaciers: a linear viscoelastic approach

    DEFF Research Database (Denmark)

    Reeh, Niels; Christensen, Erik Lintz; Mayer, Christoph

    2003-01-01

    In theoretical treatments of tidal bending of floating glaciers, the glacier is usually modelled as an elastic beam with uniform thickness, resting on an elastic foundation. With a few exceptions, values of the elastic (Young's) modulus E of ice derived from tidal deflection records of floating...

  7. The retreat of the world's mountain glaciers during recent decades

    International Nuclear Information System (INIS)

    Francou, B.; Vincent, Ch.

    2009-01-01

    Glaciers have become essential tools for measuring changes in the global environment. Here, we analyze glacier evolution during the last few decades and we wonder whether the observed retreat remains in the range of glacier fluctuations since the mid-Holocene. The main fluctuations experienced by glaciers during the last millenniums, and particularly during the Little Ice Age (-1300 A.D. to ∼1860 A.D.), are presented succinctly. The recent 1960-2005 period, well documented both by ground and remote sensing observations, shows important disparities between different massifs concerning the timing and the magnitude of glacier fluctuations, which depend on regional climatic conditions. The links between glacier mass balance evolution and climate is clear when approached from an energy balance but the variables commonly considered are only temperature and precipitation. The strong correlation existing between these variables and the mass balance evolution makes it possible to simulate glaciers in the future in function of distinct climatic scenarios. Modeling glacier retreat for the 21. century is an important goal because it will allow the impacts on water resource and sea level to be assessed. (authors)

  8. A glacier runoff extension to the Precipitation Runoff Modeling System

    Science.gov (United States)

    A. E. Van Beusekom; R. J. Viger

    2016-01-01

    A module to simulate glacier runoff, PRMSglacier, was added to PRMS (Precipitation Runoff Modeling System), a distributed-parameter, physical-process hydrological simulation code. The extension does not require extensive on-glacier measurements or computational expense but still relies on physical principles over empirical relations as much as is feasible while...

  9. Debris thickness patterns on debris-covered glaciers

    Science.gov (United States)

    Anderson, Leif S.; Anderson, Robert S.

    2018-06-01

    Many debris-covered glaciers have broadly similar debris thickness patterns: surface debris thickens and tends to transition from convex- to concave-up-down glacier. We explain this pattern using theory (analytical and numerical models) paired with empirical observations. Down glacier debris thickening results from the conveyor-belt-like nature of the glacier surface in the ablation zone (debris can typically only be added but not removed) and from the inevitable decline in ice surface velocity toward the terminus. Down-glacier thickening of debris leads to the reduction of sub-debris melt and debris emergence toward the terminus. Convex-up debris thickness patterns occur near the up-glacier end of debris covers where debris emergence dominates (ablation controlled). Concave-up debris thickness patterns occur toward glacier termini where declining surface velocities dominate (velocity controlled). A convex-concave debris thickness profile inevitably results from the transition between ablation-control and velocity-control down-glacier. Debris thickness patterns deviating from this longitudinal shape are most likely caused by changes in hillslope debris supply through time. By establishing this expected debris thickness pattern, the effects of climate change on debris cover can be better identified.

  10. Velocities of antarctic outlet glaciers determined from sequential Landsat images

    Science.gov (United States)

    MacDonald, Thomas R.; Ferrigno, Jane G.; Williams, Richard S.; Lucchitta, Baerbel K.

    1989-01-01

    Approximately 91.0 percent of the volume of present-day glacier ice on Earth is in Antarctica; Greenland contains about another 8.3 percent of the volume. Thus, together, these two great ice sheets account for an estimated 99.3 percent of the total. Long-term changes in the volume of glacier ice on our planet are the result of global climate change. Because of the relationship of global ice volume to sea level (± 330 cubic kilometers of glacier ice equals ± 1 millimeter sea level), changes in the mass balance of the antarctic ice sheet are of particular importance.Whether the mass balance of the east and west antarctic ice sheets is positive or negative is not known. Estimates of mass input by total annual precipitation for the continent have been made from scattered meteorological observations (Swithinbank 1985). The magnitude of annual ablation of the ice sheet from calving of outlet glaciers and ice shelves is also not well known. Although the velocities of outlet glaciers can be determined from field measurements during the austral summer,the technique is costly, does not cover a complete annual cycle,and has been applied to just a few glaciers. To increase the number of outlet glaciers in Antarctica for which velocities have been determined and to provide additional data for under-standing the dynamics of the antarctic ice sheets and their response to global climate change, sequential Landsat image of several outlet glaciers were measured.

  11. Effects of climate change on snowpack, glaciers, and water resources in the Northern Rockies Region [Chapter 4

    Science.gov (United States)

    Charles H. Luce

    2018-01-01

    Water is critical to life, and the effects of climate change on ecosystems are mediated through changes in hydrology. Changes in how snow accumulates and melts are one of the more consistently noted climate-induced changes to water in the western United States (Barnett et al. 2005; Service 2004), and these changes affect when water will be available for forests and...

  12. CALICE: Calibrating Plant Biodiversity in Glacier Ice

    Science.gov (United States)

    Festi, Daniela; Cristofori, Antonella; Vernesi, Cristiano; Zerbe, Stefan; Wellstein, Camilla; Maggi, Valter; Oeggl, Klaus

    2017-04-01

    The objective of the project is to reconstruct plant biodiversity and its trend archived in Alpine glacier ice by pollen and eDNA (environmental DNA) during the last five decades by analyzing a 40 m ice core. For our study we chose the Adamello glacier (Trentino - Südtirol, Lombardia) because of i) the good preservation conditions for pollen and eDNA in ice, ii) the thickness of the ice cap (270m) and iii) the expected high time resolution. The biodiversity estimates gained by pollen analysis and eDNA will be validated by historical biodiversity assessments mainly based on vegetation maps, aerial photos and vegetation surveys in the catchment area of the Adamello glacier for the last five decades. This historical reconstruction of biodiversity trends will be performed on a micro-, meso- and macro-scale (5, 20-50 and 50-100 Km radius, respectively). The results will serve as a calibration data set on biodiversity for future studies, such as the second step of the coring by the POLLiCE research consortium (pollice.fmach.it). In fact, arrangements are currently been made to drill the complete ice cap and retrieve a 270 m thick core which has the potential to cover a time span of minimum 400 years up to several millennia. This second stage will extend the time scale and enable the evaluation of dissimilarity/similarity of modern biodiversity in relation to Late Holocene trends. Finally, we believe this case study has the potential to be applied in other glaciated areas to evaluate biodiversity for large regions (e.g. central Asian mountain ranges, Tibet and Tian Shan or the Andes).

  13. The rocky flats controversy on radionuclide soil action levels

    International Nuclear Information System (INIS)

    Earle, T.C.

    2004-01-01

    This report describes how stakeholder involvement processes led to the successful resolution of a dispute over radionuclide soil action levels at the Rocky Flats Site near Denver, Colorado. During the Cold War Era, Rocky Flats, a plutonium fabrication plant, was part of the American government's multi-site nuclear weapons production facilities. Although the Rocky Flats plant had significant positive effects on the local economy, it became a target of public protest due to concerns over both public safety in the area surrounding the site and global nuclear proliferation. In the late 1980's, local safety concerns led to investigations by state and federal agencies. In 1992, with the Cold War ended, the Department of Energy decided to decommission the Rocky Flats site and to begin the long process of decontamination. (author)

  14. Why sulfonamides are contraindicated in Rocky Mountain spotted fever

    OpenAIRE

    Ren, Vicky; Hsu, Sylvia

    2014-01-01

    Sulfonamide antibiotics are not effective for the treatment of Rocky Mountain spotted fever (RMSF). Patients suspected of having RMSF based on history and physical exam should be treated with doxycycline and not a sulfonamide to avoid increased morbidity and mortality.

  15. Why sulfonamides are contraindicated in Rocky Mountain spotted fever.

    Science.gov (United States)

    Ren, Vicky; Hsu, Sylvia

    2014-02-18

    Sulfonamide antibiotics are not effective for the treatment of Rocky Mountain spotted fever (RMSF). Patients suspected of having RMSF based on history and physical exam should be treated with doxycycline and not a sulfonamide to avoid increased morbidity and mortality.

  16. Ongoing Cerebral Vasculitis During Treatment of Rocky Mountain Spotted Fever.

    Science.gov (United States)

    Sun, Lisa R; Huisman, Thierry A G M; Yeshokumar, Anusha K; Johnston, Michael V

    2015-11-01

    Rocky Mountain spotted fever is a tickborne infection that produces a systemic small-vessel vasculitis; its prognosis is excellent if appropriate treatment is initiated early. Because the advent of effective antirickettsial therapies predates the widespread use of brain magnetic resonance imaging, there are limited data on the effect of untreated Rocky Mountain spotted fever infection on neuroimaging studies. We describe a 7-year-old girl with delayed treatment of Rocky Mountain spotted fever who suffered severe neurological impairment. Serial brain magnetic resonance images revealed a progressive "starry sky appearance," which is proposed to result from the same small vessel vasculitis that causes the characteristic skin rash of this infection. Neurological injury can continue to occur despite specific antirickettsial therapy in Rocky Mountain spotted fever. This child's clinical features raise questions about the optimal management of this infection, particularly the utility of immune modulating therapies in cases of delayed treatment and neurological involvement. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Canadian seismic agreement

    International Nuclear Information System (INIS)

    Wetmiller, R.J.; Lyons, J.A.; Shannon, W.E.; Munro, P.S.; Thomas, J.T.; Andrew, M.D.; Lamontagne, M.; Wong, C.; Anglin, F.M.; Plouffe, M.; Lapointe, S.P.; Adams, J.; Drysdale, J.A.

    1990-04-01

    This is the twenty-first progress report under the agreement entitled Canadian Seismic Agreement between the US Nuclear Regulatory Commission (NRC) and the Canadian Commercial Corporation. Activities undertaken by the Geophysics Division of the Geological Survey of Canada (GD/GSC) during the period from July 01, 1988 to June 30, 1989 and supported in part by the NRC agreement are described below under four headings; Eastern Canada Telemetred Network and local network developments, Datalab developments, strong motion network developments and earthquake activity. In this time period eastern Canada experienced its largest earthquake in over 50 years. This earthquake, which has been christened the Saguenay earthquake, has provided a wealth of new data pertinent to earthquake engineering studies in eastern North America and is the subject of many continuing studies, which are presently being carried out at GD and elsewhere. 41 refs., 21 figs., 7 tabs

  18. Financing Canadian international operations

    International Nuclear Information System (INIS)

    Beagle, G.

    1996-01-01

    A primer on financing international operations by Canadian corporations was provided. Factors affecting the availability to project finance (location, political risk), the various forms of financing (debt, equity, and combinations), the main sources of government backed financing to corporations (the International Finance Corporation) (IFC), the European Bank for Reconstruction and Development (EBRD), the Asian Development Bank (ADB), the Overseas Property Insurance Corporation (OPIC), government or agency guarantees, political risk coverage, the use of offshore financial centres, and the where, when and how these various organizations operate, were reviewed. Examples of all of the above, taken from the experiences of Canadian Occidental Petroleum of Calgary in the U.S., in South America, in the Middle and Far East, and in Kazakhstan, were used as illustrations. figs

  19. Canadian Medicare: prognosis guarded.

    Science.gov (United States)

    Naylor, C D; Fooks, C; Williams, J I

    1995-08-01

    Beset by unprecedented fiscal pressures, Canadian medicare has reached a crossroads. The authors review the impact of recent cuts in federal transfer payments on provincial health care programs and offer seven suggestions to policymakers trying to accommodate these reductions. (1) Go slowly: public health care spending is no longer rising and few provinces have the necessary systems in place to manage major reductions. (2) Target reductions, rewarding quality and efficiency instead of making across-the-board cuts. (3) Replace blame with praise:give health care professionals and institutions credit for their contributions. (4) Learn from the successful programs and policies already in place across the country. (5) Foster horizontal and vertical integration of services. (6) Promote physician leadership by rewarding efforts to promote the efficient use of resources. (7) Monitor the effects of cutbacks: physician groups should cooperate with government in maintaining a national "report card" on services, costs and the health status of Canadians.

  20. Canadian fusion program

    International Nuclear Information System (INIS)

    Brown, T.S.

    1982-06-01

    The National Research Council of Canada is establishing a coordinated national program of fusion research and development that is planned to grow to a total annual operating level of about $20 million in 1985. The long-term objective of the program is to put Canadian industry in a position to manufacture sub-systems and components of fusion power reactors. In the near term the program is designed to establish a minimum base of scientific and technical expertise sufficient to make recognized contributions and thereby gain access to the international effort. The Canadian program must be narrowly focussed on a few specializations where Canada has special indigenous skills or technologies. The programs being funded are the Tokamak de Varennes, the Fusion Fuels Technology Project centered on tritium management, and high-power gas laser technology and associated diagnostic instrumentation

  1. Canadian Mathematical Congress

    CERN Document Server

    1977-01-01

    For two weeks in August, 1975 more than 140 mathematicians and other scientists gathered at the Universite de Sherbrooke. The occasion was the 15th Biennial Seminar of the Canadian Mathematical Congress, entitled Mathematics and the Life Sciences. Participants in this inter­ disciplinary gathering included researchers and graduate students in mathematics, seven different areas of biological science, physics, chemistry and medical science. Geographically, those present came from the United States and the United Kingdom as well as from academic departments and government agencies scattered across Canada. In choosing this particular interdisciplinary topic the programme committee had two chief objectives. These were to promote Canadian research in mathematical problems of the life sciences, and to encourage co-operation and exchanges between mathematical scientists" biologists and medical re­ searchers. To accomplish these objective the committee assembled a stim­ ulating programme of lectures and talks. Six ...

  2. Subglacial discharge at tidewater glaciers revealed by seismic tremor

    Science.gov (United States)

    Bartholomaus, Timothy C.; Amundson, Jason M.; Walter, Jacob I.; O'Neel, Shad; West, Michael E.; Larsen, Christopher F.

    2015-01-01

    Subglacial discharge influences glacier basal motion and erodes and redeposits sediment. At tidewater glacier termini, discharge drives submarine terminus melting, affects fjord circulation, and is a central component of proglacial marine ecosystems. However, our present inability to track subglacial discharge and its variability significantly hinders our understanding of these processes. Here we report observations of hourly to seasonal variations in 1.5–10 Hz seismic tremor that strongly correlate with subglacial discharge but not with basal motion, weather, or discrete icequakes. Our data demonstrate that vigorous discharge occurs from tidewater glaciers during summer, in spite of fast basal motion that could limit the formation of subglacial conduits, and then abates during winter. Furthermore, tremor observations and a melt model demonstrate that drainage efficiency of tidewater glaciers evolves seasonally. Glaciohydraulic tremor provides a means by which to quantify subglacial discharge variations and offers a promising window into otherwise obscured glacierized environments.

  3. Benchmarking and performance improvement at Rocky Flats Technology Site

    International Nuclear Information System (INIS)

    Elliott, C.; Doyle, G.; Featherman, W.L.

    1997-03-01

    The Rocky Flats Environmental Technology Site has initiated a major work process improvement campaign using the tools of formalized benchmarking and streamlining. This paper provides insights into some of the process improvement activities performed at Rocky Flats from November 1995 through December 1996. It reviews the background, motivation, methodology, results, and lessons learned from this ongoing effort. The paper also presents important gains realized through process analysis and improvement including significant cost savings, productivity improvements, and an enhanced understanding of site work processes

  4. Canadian Medicare: prognosis guarded.

    OpenAIRE

    Naylor, C D; Fooks, C; Williams, J I

    1995-01-01

    Beset by unprecedented fiscal pressures, Canadian medicare has reached a crossroads. The authors review the impact of recent cuts in federal transfer payments on provincial health care programs and offer seven suggestions to policymakers trying to accommodate these reductions. (1) Go slowly: public health care spending is no longer rising and few provinces have the necessary systems in place to manage major reductions. (2) Target reductions, rewarding quality and efficiency instead of making ...

  5. Canadian petroleum history bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Cass, D.

    2003-09-27

    The Petroleum History Bibliography includes a list of more than 2,000 publications that record the history of the Canadian petroleum industry. The list includes books, theses, films, audio tapes, published articles, company histories, biographies, autobiographies, fiction, poetry, humour, and an author index. It was created over a period of several years to help with projects at the Petroleum History Society. It is an ongoing piece of work, and as such, invites comments and additions.

  6. Tuberculosis in Aboriginal Canadians

    Directory of Open Access Journals (Sweden)

    Vernon H Hoeppner

    2000-01-01

    Full Text Available Endemic tuberculosis (TB was almost certainly present in Canadian aboriginal people (aboriginal Canadians denotes status Indians, Inuit, nonstatus Indians and metis as reported by Statistics Canada before the Old World traders arrived. However, the social changes that resulted from contact with these traders created the conditions that converted endemic TB into epidemic TB. The incidence of TB varied inversely with the time interval from this cultural collision, which began on the east coast in the 16th century and ended in the Northern Territories in the 20th century. This relatively recent epidemic explains why the disease is more frequent in aboriginal children than in Canadian-born nonaboriginal people. Treatment plans must account for the socioeconomic conditions and cultural characteristics of the aboriginal people, especially healing models and language. Prevention includes bacillus Calmette-Guerin vaccination and chemoprophylaxis, and must account for community conditions, such as rates of suicide, which have exceeded the rate of TB. The control of TB requires a centralized program with specifically directed funding. It must include a program that works in partnership with aboriginal communities.

  7. Canadian small wind market

    International Nuclear Information System (INIS)

    Moorhouse, E.

    2010-01-01

    This PowerPoint presentation discussed initiatives and strategies adopted by the Canadian Wind Energy Association (CanWEA) to support the development of Canada's small wind market. The general public has shown a significant interest in small wind projects of 300 kW. Studies have demonstrated that familiarity and comfort with small wind projects can help to ensure the successful implementation of larger wind projects. Small wind markets include residential, farming and commercial, and remote community applications. The results of CanWEA market survey show that the small wind market grew by 78 percent in 2008 over 2007, and again in 2009 by 32 percent over 2008. The average turbine size is 1 kW. A total of 11,000 turbines were purchased in 2007 and 2008. Global small wind market growth increased by 110 percent in 2008, and the average turbine size was 2.4 kW. Eighty-seven percent of the turbines made by Canadian mid-size wind turbine manufacturers are exported, and there is now a significant risk that Canada will lose its competitive advantage in small wind manufacturing as financial incentives have not been implemented. American and Canadian-based small wind manufacturers were listed, and small wind policies were reviewed. The presentation concluded with a set of recommendations for future incentives, educational programs and legislation. tabs., figs.

  8. Canadian ethane market overview

    Energy Technology Data Exchange (ETDEWEB)

    Stauft, T. [TransCanada Midstream, Calgary, AB (Canada)

    1999-07-01

    A review of the Canadian petrochemical industry, the supply and demand for ethane, and the longer-term outlook for ethane are presented. Recent projections of natural gas production by the National Energy Board are examined, along with the impact on ethane supply and demand by Alliance. It is suggested that reduced gas will flow past Cochrane and Empress, Alberta ethane and gas prices will increase relative to US Gulf Coast prices, and since expansion is based on ethane demand, the combined influence of these factors will be to delay the construction of new extraction capacity. Present capacity is considered sufficient to produce ethane for the current round of petrochemical plant expansions. Excess supplies will exist for the next few years, and Alberta ethane prices are likely to strengthen due to the tight supply/demand balance. The combination of the impact of the Alliance Pipeline project and the ultimate potential of the Western Canadian Sedimentary Basin are the major uncertainties. On the plus side, both the US and Canadian regulatory agencies appear to be moving away from regulating ethane, and towards allowing a competitive market to develop.

  9. Canadian ethane market overview

    International Nuclear Information System (INIS)

    Stauft, T.

    1999-01-01

    A review of the Canadian petrochemical industry, the supply and demand for ethane, and the longer-term outlook for ethane are presented. Recent projections of natural gas production by the National Energy Board are examined, along with the impact on ethane supply and demand by Alliance. It is suggested that reduced gas will flow past Cochrane and Empress, Alberta ethane and gas prices will increase relative to US Gulf Coast prices, and since expansion is based on ethane demand, the combined influence of these factors will be to delay the construction of new extraction capacity. Present capacity is considered sufficient to produce ethane for the current round of petrochemical plant expansions. Excess supplies will exist for the next few years, and Alberta ethane prices are likely to strengthen due to the tight supply/demand balance. The combination of the impact of the Alliance Pipeline project and the ultimate potential of the Western Canadian Sedimentary Basin are the major uncertainties. On the plus side, both the US and Canadian regulatory agencies appear to be moving away from regulating ethane, and towards allowing a competitive market to develop

  10. Tibetan Plateau glacier and hydrological change under stratospheric aerosol injection

    Science.gov (United States)

    Ji, D.

    2017-12-01

    As an important inland freshwater resource, mountain glaciers are highly related to human life, they provide water for many large rivers and play a very important role in regional water cycles. The response of mountain glaciers to future climate change is a topic of concern especially to the many people who rely on glacier-fed rivers for purposes such as irrigation. Geoengineering by stratospheric aerosol injection is a method of offsetting the global temperature rise from greenhouse gases. How the geoengineering by stratospheric aerosol injection affects the mass balance of mountain glaciers and adjacent river discharge is little understood. In this study, we use regional climate model WRF and catchment-based river model CaMa-Flood to study the impacts of stratospheric aerosol injection to Tibetan Plateau glacier mass balance and adjacent river discharge. To facilitate mountain glacier mass balance study, we improve the description of mountain glacier in the land surface scheme of WRF. The improvements include: (1) a fine mesh nested in WRF horizontal grid to match the highly non-uniform spatial distribution of the mountain glaciers, (2) revising the radiation flux at the glacier surface considering the surrounding terrain. We use the projections of five Earth system models for CMIP5 rcp45 and GeoMIP G4 scenarios to drive the WRF and CaMa-Flood models. The G4 scenario, which uses stratospheric aerosols to reduce the incoming shortwave while applying the rcp4.5 greenhouse gas forcing, starts stratospheric sulfate aerosol injection at a rate of 5 Tg per year over the period 2020-2069. The ensemble projections suggest relatively slower glacier mass loss rates and reduced river discharge at Tibetan Plateau and adjacent regions under geoengineering scenario by stratospheric aerosol injection.

  11. The energy balance on the surface of a tropical glacier tongue. Investigations on glacier Artesonraju, Cordillera Blanca, Perú.

    Science.gov (United States)

    Juen, I.; Mölg, T.; Wagnon, P.; Cullen, N. J.; Kaser, G.

    2006-12-01

    The Cordillera Blanca in Perú is situated in the Outer Tropics spanning from 8 to 10 ° South. Solar incidence and air temperature show only minor seasonal variations whereas precipitation occurs mainly from October to April. An energy balance station was installed on the tongue of glacier Artesonraju (4850 m a.s.l.) in March 2004. In this study each component of the energy balance on the glacier surface is analysed separately over a full year, covering one dry and one wet season. During the dry season glacier melt at the glacier tongue is app. 0.5 m we per month. In the wet season glacier melt is twice as much with 1 m we per month. This is due to higher energy fluxes and decreased sublimation during the wet season. With an energy balance model that has already been proved under tropical climate conditions (Mölg and Hardy, 2004) each energy flux is changed individually to evaluate the change in the amount of glacier melt. First results indicate that a change in humidity related variables affects glacier melt very differently in the dry and wet season, whereas a change in air temperature changes glacier melt more constantly throughout the year.

  12. KEPLER'S FIRST ROCKY PLANET: KEPLER-10b

    International Nuclear Information System (INIS)

    Batalha, Natalie M.; Borucki, William J.; Bryson, Stephen T.; Haas, Michael R.; Koch, David G.; Lissauer, Jack J.; Rowe, Jason F.; Buchhave, Lars A.; Fressin, Francois; Latham, David W.; Caldwell, Douglas A.; Jenkins, Jon M.; Christensen-Dalsgaard, Joergen; Kjeldsen, Hans; Ciardi, David; Dunham, Edward W.; Gautier, Thomas N. III; Gilliland, Ronald L.; Howell, Steve B.; Marcy, Geoffrey W.

    2011-01-01

    NASA's Kepler Mission uses transit photometry to determine the frequency of Earth-size planets in or near the habitable zone of Sun-like stars. The mission reached a milestone toward meeting that goal: the discovery of its first rocky planet, Kepler-10b. Two distinct sets of transit events were detected: (1) a 152 ± 4 ppm dimming lasting 1.811 ± 0.024 hr with ephemeris T [BJD] =2454964.57375 +0.00060 -0.00082 + N*0.837495 +0.000004 -0.000005 days and (2) a 376 ± 9 ppm dimming lasting 6.86 ± 0.07 hr with ephemeris T [BJD] =2454971.6761 +0.0020 -0.0023 + N*45.29485 +0.00065 -0.00076 days. Statistical tests on the photometric and pixel flux time series established the viability of the planet candidates triggering ground-based follow-up observations. Forty precision Doppler measurements were used to confirm that the short-period transit event is due to a planetary companion. The parent star is bright enough for asteroseismic analysis. Photometry was collected at 1 minute cadence for >4 months from which we detected 19 distinct pulsation frequencies. Modeling the frequencies resulted in precise knowledge of the fundamental stellar properties. Kepler-10 is a relatively old (11.9 ± 4.5 Gyr) but otherwise Sun-like main-sequence star with T eff = 5627 ± 44 K, M * = 0.895 ± 0.060 M sun , and R * = 1.056 ± 0.021 R sun . Physical models simultaneously fit to the transit light curves and the precision Doppler measurements yielded tight constraints on the properties of Kepler-10b that speak to its rocky composition: M P = 4.56 +1.17 -1.29 M + , R P = 1.416 +0.033 -0.036 R + , and ρ P = 8.8 +2.1 -2.9 g cm -3 . Kepler-10b is the smallest transiting exoplanet discovered to date.

  13. Dictionaries of Canadian English

    Directory of Open Access Journals (Sweden)

    John Considine

    2011-10-01

    Full Text Available

    Abstract: The lexicographical record of English in Canada began with wordlists of the late eighteenth, nineteenth, and early twentieth centuries. From the beginning of the twentieth century onwards, the general vocabulary of English in Canada has been represented in bilingual and monolingual dictionaries, often adapted from American or British dictionaries. In the 1950s, several important projects were initiated, resulting in the publication of general dictionaries of English in Canada, and of dictionaries of Canadianisms and of the vocabulary of particular regions of Can-ada. This article gives an overview of these dictionaries and of their reception, contextualizing them in the larger picture of the lexicography of Canada's other official language, French, and of a number of its non-official languages. It concludes by looking at the future of English-language lexicography in Canada, and by observing that although it has, at its best, reached a high degree of sophistication, there are still major opportunities waiting to be taken.

    Keywords: DICTIONARY, LEXICOGRAPHY, CANADIAN ENGLISH, CANADIANISMS, NATIONAL DICTIONARIES, CANADIAN FRENCH, CANADIAN FIRST NATIONS LAN-GUAGES, BILINGUAL DICTIONARIES, REGIONAL DICTIONARIES, UNFINISHED DICTIONARY PROJECTS

    Opsomming: Woordeboeke van Kanadese Engels. Die leksikografiese optekening van Engels in Kanada begin met woordelyste van die laat agtiende, neëntiende en vroeë twintigste eeue. Van die begin van die twintigste eeu af en verder, is die algemene woordeskat van Engels weergegee in tweetalige en eentalige woordeboeke, dikwels met wysiginge ontleen aan Ameri-kaanse en Britse woordeboeke. In die 1950's is verskeie belangrike projekte onderneem wat gelei het tot die publikasie van algemene woordeboeke van Engels in Kanada, en van woordeboeke van Kanadeïsmes en van die woordeskat van bepaalde streke van Kanada. Hierdie artikel gee 'n oorsig van dié woordeboeke, en van hul ontvangs, deur

  14. Geographic Names of Iceland's Glaciers: Historic and Modern

    Science.gov (United States)

    Sigurðsson, Oddur; Williams, Richard S.

    2008-01-01

    Climatic changes and resulting glacier fluctuations alter landscapes. In the past, such changes were noted by local residents who often documented them in historic annals; eventually, glacier variations were recorded on maps and scientific reports. In Iceland, 10 glacier place-names are to be found in Icelandic sagas, and one of Iceland's ice caps, Snaefellsjokull, appeared on maps of Iceland published in the 16th century. In the late 17th century, the first description of eight of Iceland's glaciers was written. Therefore, Iceland distinguishes itself in having a more than 300-year history of observations by Icelanders on its glaciers. A long-term collaboration between Oddur Sigurdsson and Richard S. Williams, Jr., led to the authorship of three books on the glaciers of Iceland. Much effort has been devoted to documenting historical glacier research and related nomenclature and to physical descriptions of Icelandic glaciers by Icelanders and other scientists from as far back as the Saga Age to recent (2008) times. The first book, Icelandic Ice Mountains, was published by the Icelandic Literary Society in 2004 in cooperation with the Icelandic Glaciological Society and the International Glaciological Society. Icelandic Ice Mountains was a glacier treatise written by Sveinn Palsson in 1795 and is the first English translation of this important scientific document. Icelandic Ice Mountains includes a Preface, including a summary of the history and facsimiles of page(s) from the original manuscript, a handwritten copy, and an 1815 manuscript (without maps and drawings) by Sveinn Palsson on the same subject which he wrote for Rev. Ebenezer Henderson; an Editor's Introduction; 82 figures, including facsimiles of Sveinn Palsson's original maps and perspective drawings, maps, and photographs to illustrate the text; a comprehensive Index of Geographic Place-Names and Other Names in the treatise; References, and 415 Endnotes. Professional Paper 1746 (this book) is the second

  15. Rock Glacier Response to Climate Change in the Argentinian Andes

    Science.gov (United States)

    Drewes, J.; Korup, O.; Moreiras, S.

    2017-12-01

    Rock glaciers are bodies of frozen debris and ice that move under the influence of gravity in permafrost areas. Rock glaciers may store a large amount of sediments and play an important role as prime movers of debris in the Andean sediment cascade. However, little is known about how much sediment and water rock glaciers may store at the mountain-belt scale, and the few existing estimates vary considerably. We address this question for the Argentinian Andes, for which a new glacial inventory containing more than 6500 rock glaciers gives us the opportunity to analyse their relevance within the sediment cascade. We examine the inventory for catchments in five sub-regions, i.e. the Desert Andes (22°-31°S); the Central Andes (31°-36°S); the Northern Andes of Patagonia (36°-45°S); the Southern Andes of Patagonia (45°-52°S); and Tierra del Fuego (52°-55°S), together with climate variables of the WorldClim datasets, and digital topographic data, to estimate how rock-glacier extents may change under different past and future climate scenarios. We observe for the northern Desert Andes that rock glacier toes are at 4000 to 5000 m a.s.l. and a mean annual temperature range of 3° and 8°C, though most rock glaciers are in areas with mean annual temperatures between -5 and 5°C, marking a distinct thermal niche. Rock glaciers are traditionally viewed as diagnostic of sporadic alpine permafrost and their toes are often near the annual mean 0°C isotherm. However, we find that only rock glaciers in the southern Desert Andes and Central Andes are located where annual mean temperature is -2°C. Future scenarios project an increase of > four degrees in these areas, which may further degrade ground ice and potentially change the rates at which rock glaciers advance. Where active rock glaciers become inactive their coarse material, which was formerly bound by ice, may be released into the sediment cascade, whereas accelerating or rapidly downwasting rock glaciers may either

  16. Contrasting medial moraine development at adjacent temperate, maritime glaciers: Fox and Franz Josef Glaciers, South Westland, New Zealand

    Science.gov (United States)

    Brook, Martin; Hagg, Wilfried; Winkler, Stefan

    2017-08-01

    Medial moraines form important pathways for sediment transportation in valley glaciers. Despite the existence of well-defined medial moraines on several glaciers in the New Zealand Southern Alps, medial moraines there have hitherto escaped attention. The evolving morphology and debris content of medial moraines on Franz Josef Glacier and Fox Glacier on the western flank of the Southern Alps is the focus of this study. These temperate maritime glaciers exhibit accumulation zones of multiple basins that feed narrow tongues flowing down steep valleys and terminate 400 m above sea level. The medial moraines at both glaciers become very prominent in the lower ablation zones, where the medial moraines widen, and develop steeper flanks coeval with an increase in relative relief. Medial moraine growth appears somewhat self-limiting in that relief and slope angle increase eventually lead to transport of debris away from the medial moraine by mass-movement-related processes. Despite similarities in overall morphologies, a key contrast in medial moraine formation exists between the two glaciers. At Fox Glacier, the medial moraine consists of angular rockfall-derived debris, folded to varying degrees along flow-parallel axes throughout the tongue. The debris originates above the ELA, coalesces at flow-unit boundaries, and takes a medium/high level transport pathway before subsequently emerging at point-sources aligned with gently dipping fold hinges near the snout. In contrast at Franz Josef Glacier, the medial moraine emerges farther down-glacier immediately below a prominent rock knob. Clasts show a mix of angular to rounded shapes representing high level transport and subglacially transported materials, the latter facies possibly also elevated by supraglacial routing of subglacial meltwater. Our observations confirm that a variety of different debris sources, transport pathways, and structural glaciological processes can interact to form medial moraines within New Zealand

  17. LHC Report: Rocky re-start

    CERN Multimedia

    Barbara Holzer for the LHC Team

    2012-01-01

    A rocky re-start with beam followed a successful machine development period and the first technical stop of 2012. Today, Friday 11 May, the machine began running again with 1380 bunches.   A short, two-day machine development period was successfully completed on 21-22 April. It focused on topics relevant for the 2012 physics beam operation. This was then followed by a five-day technical stop, the first of the year. The technical stop finished on time on Friday 26 April. The re-start with beam was somewhat tortuous and hampered by an unlucky succession of technical faults leading to extended periods of downtime. The planned intensity increase was put on hold for three days with the machine operating with 1092 bunches and a moderate bunch intensity of 1.3x1011 protons. This delivered a reasonable peak luminosity of 3.6x1033 cm-2s-1 to ATLAS and CMS. Higher than usual beam losses were observed in the ramp and squeeze, and time was required to investigate the causes and to implement mitigati...

  18. Elemental compositions of two extrasolar rocky planetesimals

    Energy Technology Data Exchange (ETDEWEB)

    Xu, S.; Jura, M.; Klein, B.; Zuckerman, B. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1562 (United States); Koester, D., E-mail: sxu@astro.ucla.edu, E-mail: jura@astro.ucla.edu, E-mail: kleinb@astro.ucla.edu, E-mail: ben@astro.ucla.edu, E-mail: koester@astrophysik.uni-kiel.de [Institut fur Theoretische Physik und Astrophysik, University of Kiel, D-24098 Kiel (Germany)

    2014-03-10

    We report Keck/HIRES and Hubble Space Telescope/COS spectroscopic studies of extrasolar rocky planetesimals accreted onto two hydrogen atmosphere white dwarfs, G29-38 and GD 133. In G29-38, eight elements are detected, including C, O, Mg, Si, Ca, Ti, Cr, and Fe while in GD 133, O, Si, Ca, and marginally Mg are seen. These two extrasolar planetesimals show a pattern of refractory enhancement and volatile depletion. For G29-38, the observed composition can be best interpreted as a blend of a chondritic object with some refractory-rich material, a result from post-nebular processing. Water is very depleted in the parent body accreted onto G29-38, based on the derived oxygen abundance. The inferred total mass accretion rate in GD 133 is the lowest of all known dusty white dwarfs, possibly due to non-steady state accretion. We continue to find that a variety of extrasolar planetesimals all resemble to zeroth order the elemental composition of bulk Earth.

  19. Rocky Flats Plant fluidized-bed incinerator

    International Nuclear Information System (INIS)

    Meile, L.J.; Meyer, F.G.; Johnson, A.J.; Ziegler, D.L.

    1982-01-01

    Laboratory and pilot-scale testing of a fluidized-bed incineration process for radioactive wastes led to the installation of an 82-kg/hr demonstration unit at Rocky Flats Plant in 1978. Design philosophy and criteria were formulated to fulfill the needs and objectives of an improved radwaste-incineration system. Unique process concepts include low-temperature (550 0 C), flameless, fluidized-bed combustion and catalytic afterburning; in-situ neutralization of acid gases; and dry off-gas cleanup. Detailed descriptions of the process and equipment are presented along with a summary of the equipment and process performance during a 2-1/2 year operational-testing period. Equipment modifications made during the test period are described. Operating personnel requirements for solid-waste burning are shown to be greater than those required for liquid-waste incineration; differences are discussed. Process-utility and raw-materials consumption rates for full-capacity operation are presented and explained. Improvements in equipment and operating procedures are recommended for any future installations. Process flow diagrams, an area floor plan, a process-control-system schematic, and equipment sketches are included

  20. The HARPS-N Rocky Planet Search

    DEFF Research Database (Denmark)

    Motalebi, F.; Udry, S.; Gillon, M.

    2015-01-01

    We know now from radial velocity surveys and transit space missions that planets only a few times more massive than our Earth are frequent around solar-type stars. Fundamental questions about their formation history, physical properties, internal structure, and atmosphere composition are, however......, still to be solved. We present here the detection of a system of four low-mass planets around the bright (V = 5.5) and close-by (6.5 pc) star HD 219134. This is the first result of the Rocky Planet Search programme with HARPS-N on the Telescopio Nazionale Galileo in La Palma. The inner planet orbits...... on a close-in, quasi-circular orbit with a period of 6.767 ± 0.004 days. The third planet in the system has a period of 46.66 ± 0.08 days and a minimum-mass of 8.94 ± 1.13 M⊕, at 0.233 ± 0.002 AU from the star. Its eccentricity is 0.46 ± 0.11. The period of this planet is close to the rotational period...

  1. Rocky Planet Formation: Quick and Neat

    Science.gov (United States)

    Kenyon, Scott J.; Najita, Joan R.; Bromley, Benjamin C.

    2016-11-01

    We reconsider the commonly held assumption that warm debris disks are tracers of terrestrial planet formation. The high occurrence rate inferred for Earth-mass planets around mature solar-type stars based on exoplanet surveys (˜20%) stands in stark contrast to the low incidence rate (≤2%-3%) of warm dusty debris around solar-type stars during the expected epoch of terrestrial planet assembly (˜10 Myr). If Earth-mass planets at au distances are a common outcome of the planet formation process, this discrepancy suggests that rocky planet formation occurs more quickly and/or is much neater than traditionally believed, leaving behind little in the way of a dust signature. Alternatively, the incidence rate of terrestrial planets has been overestimated, or some previously unrecognized physical mechanism removes warm dust efficiently from the terrestrial planet region. A promising removal mechanism is gas drag in a residual gaseous disk with a surface density ≳10-5 of the minimum-mass solar nebula.

  2. Commercial Decommissioning at DOE's Rocky Flats

    International Nuclear Information System (INIS)

    Freiboth, C.; Sandlin, N.; Schubert, A.; Hansen, S.

    2002-01-01

    Due in large part to the number of nuclear facilities that make up the DOE complex, DOE-EM work has historically been paperwork intensive and driven by extensive regulations. Requirements for non-nuclear facilities are often grouped with those of nuclear facilities, driving up costs. Kaiser-Hill was interested in applying a commercial model to demolition of these facilities and wanted to apply necessary and sufficient standards to the work activities, but avoid applying unnecessary requirements. Faced with demolishing hundreds of uncontaminated or non-radiologically contaminated facilities, Kaiser-Hill has developed a subcontracting strategy to drastically reduce the cost of demolishing these facilities at Rocky Flats. Aiming to tailor the demolition approach of such facilities to more closely follow commercial practices, Kaiser-Hill recently released a Request for Proposals (RFP) for the demolition of the site's former central administration facility. The RFP significantly reduced requirements for compliance with specific DOE directives. Instead, the RFP required subcontractors to comply with health and safety requirements commonly found in the demolition of similar facilities in a commercial setting. This resulted in a number of bids from companies who have normally not bid on DOE work previously and at a reduced cost over previous approaches. This paper will discuss the details of this subcontracting strategy

  3. The length of the world's glaciers - a new approach for the global calculation of center lines

    DEFF Research Database (Denmark)

    Machguth, Horst; Huss, M.

    2014-01-01

    length using an automated method that relies on glacier surface slope, distance to the glacier margins and a set of trade-off functions. The method is developed for East Greenland, evaluated for East Greenland as well as for Alaska and eventually applied to all similar to 200 000 glaciers around...... appear to be related to characteristics of topography and glacier mass balance. The present study adds glacier length as a key parameter to global glacier inventories. Global and regional scaling laws might prove beneficial in conceptual glacier models....

  4. Exploring the links between transient water inputs and glacier velocity in a small temperate glacier in southeastern Alaska

    Science.gov (United States)

    Heavner, M.; Habermann, M.; Hood, E. W.; Fatland, D. R.

    2009-12-01

    Glaciers along the Gulf of Alaska are thinning and retreating rapidly. An important control on the rate at which ice is being lost is basal motion because higher glacier velocities increase the rate at which ice is delivered to ablation zones. Recent research has focused on understanding the effects of sub-glacial water storage on glacier basal motion. In this study, we examined two seasons of the effect of hydrologic controls (from large rainfall events as well as a glacier lake outburst floods) on the velocity of the Lemon Creek Glacier in southeastern Alaska. Lemon Creek Glacier is a moderately sized (~16~km2) temperate glacier at the margin of the Juneau Icefield. An ice-marginal lake forms at the head of the glacier and catastrophically drains once or twice every melt season. We have instrumented the glacier with two meteorological stations: one at the head of the glacier near the ice-marginal lake and another several kilometers below the terminus. These stations measure temperature, relative humidity, precipitation, incoming solar radiation and wind speed and direction. Lake stage in the ice-marginal lake was monitored with a pressure transducer. In addition, Lemon Creek was instrumented with a water quality sonde at the location of a US Geological Survey gaging station approximately 3 km downstream from the glacier terminus. The sonde provides continuous measurements of water temperature, dissolved oxygen, turbidity and conductivity. Finally, multiple Trimble NetRS dual frequency, differential GPS units were deployed on the glacier along the centerline of the glacier. All of the instruments were run continuously from May-September 2008 and May-September 2009 and captured threee outburst floods associated with the ice-marginal lake drainage as well as several large (>3~cm) rainfall events associated with frontal storms off of the Gulf of Alaska in late summer. Taken together, these data allow us to test the hypothesis that water inputs which overwhelm

  5. Rocky desertification in Southwest China: Impacts, causes, and restoration

    Science.gov (United States)

    Jiang, Zhongcheng; Lian, Yanqing; Qin, Xiaoqun

    2014-05-01

    Rocky desertification, which is relatively less well known than desertification, refers to the processes and human activities that transform a karst area covered by vegetation and soil into a rocky landscape. It has occurred in various countries and regions, including the European Mediterranean and Dinaric Karst regions of the Balkan Peninsula, Southwest China on a large scale, and alarmingly, even in tropical rainforests such as Haiti and Barbados, and has had tremendous negative impacts to the environment and social and economic conditions at local and regional scales. The goal of this paper is to provide a thorough review of the impacts, causes, and restoration measures of rocky desertification based on decades of studies in the southwest karst area of China and reviews of studies in Europe and other parts of the world. The low soil formation rate and high permeability of carbonate rocks create a fragile and vulnerable environment that is susceptible to deforestation and soil erosion. Other natural processes related to hydrology and ecology could exacerbate rocky desertification. However, disturbances from a wide variety of human activities are ultimately responsible for rocky desertification wherever it has occurred. This review shows that reforestation can be successful in Southwest China and even in the Dinaric Karst region when the land, people, water, and other resources are managed cohesively. However, new challenges may arise as more frequent droughts and extreme floods induced by global climate change and variability may slow the recovery process or even expand rocky desertification. This review is intended to bring attention to this challenging issue and provide information needed to advance research and engineering practices to combat rocky desertification and to aid in sustainable development.

  6. Glaciers of Avacha group of volcanoes in Neoholocene

    Directory of Open Access Journals (Sweden)

    T. M. Manevich

    2016-01-01

    Full Text Available The study of moraines at the Avacha volcano group revealed that glaciers changes at all volcanoes within the group happened almost synchronously. Glacial deposits could be grouped into three generations, corresponding to three periods of glacier fluctuations in Neoholocene. The largest glaciation within the group occurred ~2000 years ago. Fragments of moraine, corresponding to that period were found only in the moraine complex of the Ditmar Glacier which was 15% larger then today at that time. The most of moraines at the Avacha volcano group were formed during the Little Ice Age, which in the studied region continued up to the first decades of XX centuries. The maximal advance of glaciers probably happened in XVII century. The moraine corresponding to that period was found at the Kozelsky Glacier valley. At present time the total area of glaciers which moraines were described and dated approaches 21.46  km2. The area of reconstructed moraines corresponding to the Little Ice Age is estimated to be 2.79 km2, therefore at that period the total glaciation area reaches 24,25 км2 exceeding the present area by 13%. It could be claimed that in general during the time past the Little Ice Age the glaciation nature and glacier types did not change sufficiently. The rate of glacier degradation at various parts of the group is different and depends mainly on exposition. At the valleys of four glaciers we found moraines formed in the middle of XX century. They may appear in 1941–1952 when the unfavorable weather conditions leaded to stable negative anomalies in accumulation have happened.

  7. Canadian heavy water production

    International Nuclear Information System (INIS)

    Dahlinger, A.; Lockerby, W.E.; Rae, H.K.

    1977-01-01

    The paper reviews Canadian experience in the production of heavy water, presents a long-term supply projection, relates this projection to the anticipated long-term electrical energy demand, and highlights principal areas for further improvement that form the bulk of the Canadian R and D programme on heavy water processes. Six Canadian heavy water plants with a total design capacity of 4000Mg/a are in operation or under construction. All use the Girdler-Sulphide (GS) process, which is based on deuterium exchange between water and hydrogen sulphide. Early operating problems have been overcome and the plants have demonstrated annual capacity factors in excess of 70%, with short-term production rates equal to design rates. Areas for further improvement are: to increase production rates by optimizing the control of foaming to give both higher sieve tray efficiency and higher flow rates, to reduce the incapacity due to deposition of pyrite (FeS 2 ) and sulphur (between 5% and 10%), and to improve process control and optimization of operating conditions by the application of mathematical simulations of the detailed deuterium profile throughout each plant. Other processes being studied, which look potentially attractive are the hydrogen-water exchange and the hydrogen-amine exchange. Even if they become successful competitors to the GS process, the latter is likely to remain the dominant production method for the next 10-20 years. This programme, when related to the long-term electricity demand, indicates that heavy water supply and demand are in reasonable balance and that the Candu programme will not be inhibited because of shortages of this commodity. (author)

  8. The Canadian safeguards program

    International Nuclear Information System (INIS)

    Zarecki, C.W.; Smith, R.M.

    1981-12-01

    In support of the Treaty on the Non-Proliferation of Nuclear Weapons Canada provides technical support to the International Atomic Energy Agency for the development of safeguards relevant to Canadian designed and built nuclear facilities. Some details of this program are discussed, including the philosophy and development of CANDU safeguards systems; the unique equipment developed for these systems; the provision of technical experts; training programs; liaison with other technical organizations; research and development; implementation of safeguards systems at various nuclear facilities; and the anticipated future direction of the safeguards program

  9. Canadian photovoltaic industry directory

    International Nuclear Information System (INIS)

    1998-01-01

    This directory has been prepared to help potential photovoltaic (PV) customers identify Canadian-based companies who can meet their needs, and to help product manufacturers and distributors identify potential new clients and/or partners within the PV industry for new and improved technologies. To assist the reader, an information matrix is provided that identifies the product and service types offered by each firm and its primary clients served. A list of companies by province or territory is also included. The main section lists companies in alphabetical order. Information presented for each includes address, contact person, prime activity, geographic area served, languages in which services are offered, and a brief company profile

  10. Distribution and transportation of mercury from glacier to lake in the Qiangyong Glacier Basin, southern Tibetan Plateau, China.

    Science.gov (United States)

    Sun, Shiwei; Kang, Shichang; Huang, Jie; Li, Chengding; Guo, Junming; Zhang, Qianggong; Sun, Xuejun; Tripathee, Lekhendra

    2016-06-01

    The Tibetan Plateau is home to the largest aggregate of glaciers outside the Polar Regions and is a source of fresh water to 1.4 billion people. Yet little is known about the transportation and cycling of Hg in high-elevation glacier basins on Tibetan Plateau. In this study, surface snow, glacier melting stream water and lake water samples were collected from the Qiangyong Glacier Basin. The spatiotemporal distribution and transportation of Hg from glacier to lake were investigated. Significant diurnal variations of dissolved Hg (DHg) concentrations were observed in the river water, with low concentrations in the morning (8:00am-14:00pm) and high concentrations in the afternoon (16:00pm-20:00pm). The DHg concentrations were exponentially correlated with runoff, which indicated that runoff was the dominant factor affecting DHg concentrations in the river water. Moreover, significant decreases of Hg were observed during transportation from glacier to lake. DHg adsorption onto particulates followed by the sedimentation of particulate-bound Hg (PHg) could be possible as an important Hg removal mechanism during the transportation process. Significant decreases in Hg concentrations were observed downstream of Xiao Qiangyong Lake, which indicated that the high-elevation lake system could significantly affect the distribution and transportation of Hg in the Qiangyong Glacier Basin. Copyright © 2016. Published by Elsevier B.V.

  11. High Artic Glaciers and Ice Caps Ice Mass Change from GRACE, Regional Climate Model Output and Altimetry.

    Science.gov (United States)

    Ciraci, E.; Velicogna, I.; Fettweis, X.; van den Broeke, M. R.

    2016-12-01

    The Arctic hosts more than the 75% of the ice covered regions outside from Greenland and Antarctica. Available observations show that increased atmospheric temperatures during the last century have contributed to a substantial glaciers retreat in all these regions. We use satellite gravimetry by the NASA's Gravity Recovery and Climate Experiment (GRACE), and apply a least square fit mascon approach to calculate time series of ice mass change for the period 2002-2016. Our estimates show that arctic glaciers have constantly contributed to the sea level rise during the entire observation period with a mass change of -170+/-20 Gt/yr equivalent to the 80% of the total ice mass change from the world Glacier and Ice Caps (GIC) excluding the Ice sheet peripheral GIC, which we calculated to be -215+/-32 GT/yr, with an acceleration of 9+/-4 Gt/yr2. The Canadian Archipelago is the main contributor to the total mass depletion with an ice mass trend of -73+/-9 Gt/yr and a significant acceleration of -7+/-3 Gt/yr2. The increasing mass loss is mainly determined by melting glaciers located in the northern part of the archipelago.In order to investigate the physical processes driving the observed ice mass loss we employ satellite altimetry and surface mass balance (SMB) estimates from Regional climate model outputs available for the same time period covered by the gravimetry data. We use elevation data from the NASA ICESat (2003-2009) and ESA CryoSat-2 (2010-2016) missions to estimate ice elevation changes. We compare GRACE ice mass estimates with time series of surface mass balance from the Regional Climate Model (RACMO-2) and the Modèle Atmosphérique Régional (MAR) and determine the portion of the total mass change explained by the SMB signal. We find that in Iceland and in the and the Canadian Archipelago the SMB signal explains most of the observed mass changes, suggesting that ice discharge may play a secondary role here. In other region, e.g. in Svalbar, the SMB signal

  12. Ice thickness measurements and volume estimates for glaciers in Norway

    Science.gov (United States)

    Andreassen, Liss M.; Huss, Matthias; Melvold, Kjetil; Elvehøy, Hallgeir; Winsvold, Solveig H.

    2014-05-01

    Whereas glacier areas in many mountain regions around the world now are well surveyed using optical satellite sensors and available in digital inventories, measurements of ice thickness are sparse in comparison and a global dataset does not exist. Since the 1980s ice thickness measurements have been carried out by ground penetrating radar on many glaciers in Norway, often as part of contract work for hydropower companies with the aim to calculate hydrological divides of ice caps. Measurements have been conducted on numerous glaciers, covering the largest ice caps as well as a few smaller mountain glaciers. However, so far no ice volume estimate for Norway has been derived from these measurements. Here, we give an overview of ice thickness measurements in Norway, and use a distributed model to interpolate and extrapolate the data to provide an ice volume estimate of all glaciers in Norway. We also compare the results to various volume-area/thickness-scaling approaches using values from the literature as well as scaling constants we obtained from ice thickness measurements in Norway. Glacier outlines from a Landsat-derived inventory from 1999-2006 together with a national digital elevation model were used as input data for the ice volume calculations. The inventory covers all glaciers in mainland Norway and consists of 2534 glaciers (3143 glacier units) covering an area of 2692 km2 ± 81 km2. To calculate the ice thickness distribution of glaciers in Norway we used a distributed model which estimates surface mass balance distribution, calculates the volumetric balance flux and converts it into thickness using the flow law for ice. We calibrated this model with ice thickness data for Norway, mainly by adjusting the mass balance gradient. Model results generally agree well with the measured values, however, larger deviations were found for some glaciers. The total ice volume of Norway was estimated to be 275 km3 ± 30 km3. From the ice thickness data set we selected

  13. The Aysen Glacier Trail (AGT): Fostering leadership and personal growth towards understanding our place in the environment through experiential learning and scientific inquiry in northern Patagonia, Chile

    Science.gov (United States)

    Sincavage, R.; Chambers, F. B.; Leidich, J.

    2017-12-01

    The Colonia Glacier, a low elevation mid-latitude glacier, drains the lee side of the central division of the Northern Patagonian Ice Field (NPI). As such, it serves as a microcosm of conditions on the NPI as a whole. Glaciers of this type have experienced extreme variability in Holocene thickness and extent, making them excellent indicators of local and regional climate conditions. Glacial lake outburst floods (GLOFs) originating in the remote Cachet Basin, dammed by the Colonia Glacier, have increased in frequency from once every 10 years to 3 times annually since 2008. These flood events are important in that they 1.) directly impact the livelihoods of downstream residents, 2.) may be linked to the overall health of the Colonia Glacier and, to a larger extent, the NPI, 3.) provide a natural laboratory for studying the dynamics of large flood events, and 4.) have downcut the sediments sequestered in the upper basin, revealing a rich Holocene sedimentologic and climate record. With improved access to this remote region through local partners in recent years, outstanding opportunities for scientific discovery, education, and outreach exist in one of the most beautiful and least-studied glacial regions on Earth. We propose establishing an NSF REU site here to further develop the abundant educational and research opportunities in this spectacular locale. We envision students participating under the REU will receive a broad-based background in glaciology and sedimentology prior to the field experience, and then participate in basic field research led by the PIs into understanding recent and Holocene linkages between climate change and the glacio-fluvio geomorphology of the NPI. A pilot program of 13 U.S. and Chilean students with wide-ranging backgrounds and degree levels was conducted in the winter of 2015-16. A two week backcountry trek across rocky terrain, mountain streams, active glaciers, and proglacial lakes in this seldom-visited region immersed the students

  14. Seismic observations of subglacial water discharge from glacier-dammed lake drainage at Lemon Creek Glacier, Alaska

    Science.gov (United States)

    Labedz, C. R.; Bartholomaus, T. C.; Gimbert, F.; Amundson, J. M.; Vore, M. E.; Karplus, M. S.; Tsai, V. C.

    2017-12-01

    Subglacial water flow affects the dynamics of glaciers, influencing basal sliding, sediment transport, fracturing, and terminus dynamics. However, the difficulty of directly observing glacial hydrologic systems creates significant challenges in understanding such glacier behavior. Recently-developed descriptions of ground motion generated by subglacial water flow provide a promising basis for new and unique characterization of glacial hydrologic systems. Particularly, high-frequency ( 1.5-20 Hz) seismic tremor observed near glaciers has been shown to correlate with subglacial runoff. In addition, specific properties of subglacial water flow like water pressure, conduit size, sediment flux, and grain size can be inferred by examining hysteretic behavior over time between different parts of these signals. In this study, we observe the seismic signals generated by subglacial water flow using a high-density array of more than 100 nodes deployed for 10-25 days, and six broadband seismometers deployed for 80 days at Lemon Creek Glacier, Alaska. Specifically, we examine the 36-hour drainage of a glacier-dammed lake into subglacial conduits, comparing hydrologic metrics such as lake level, precipitation, and outlet stream flow rate to the power of seismic signals. Our node array captures this annually-significant hydraulic transient with sensors spaced approximately every 250 m over the majority of the 5.7 km long glacier. This and other lake drainage events provide natural experiments for exploring glaciohydraulic tremor, because the increased water flux through the glacier increases the power of the tremor and hosts the hysteretic behaviors described previously. Analysis of the tremor from events such as this can be extended to further understand subglacial runoff at Lemon Creek glacier and for glacier hydrology in general.

  15. On Realities of Canadian Multiculturalism

    Institute of Scientific and Technical Information of China (English)

    李梦辰

    2013-01-01

    Canada is a multicultural country which was mainly established by immigrants. Just because of that, Canadian govern⁃ment has carried out the policy of multiculturalism since1970s. However, it has encountered many problems such as policy con⁃flicts, national identity, democracy-inquiry and racial discrimination, etc. Hence the Canadian multiculturalism has been in a di⁃lemma.

  16. "Canadianizing" an American Communication Textbook.

    Science.gov (United States)

    Maclennan, Jennifer M.

    2000-01-01

    Presents a study on the process involved in the "Canadianization" of U.S. textbooks for the domestic market. Explores whether disciplinary values have been shaped by the United States in the field of communication. Focuses on the experience of developing the Canadian edition of the book "Public Speaking: Strategies for Success"…

  17. Engendering migrant health: Canadian perspectives

    National Research Council Canada - National Science Library

    Spitzer, Denise L

    2011-01-01

    ... these and other issues at the intersections of gender, immigration, and health in the lives of new Canadians. Situating their work within the context of Canadian policy and society, the contributors illuminate migrants' testimonies of struggle, resistance, and solidarity as they negotiate a place for themselves in a new country. Topics range fr...

  18. Canadian perspectives on food irradiation

    International Nuclear Information System (INIS)

    Kunstadt, P.

    1988-01-01

    Canada has been in the forefront of irradiation technology for some 30 years. Nearly 90 of the 140 irradiators used worldwide are Canadian-built, yet Canadian food processors have been very slow to use the technology. The food irradiation regulatory situation in Canada, the factors that influence it, and some significant non-regulatory developments are reviewed. (author)

  19. Canadian geologic isolation program

    International Nuclear Information System (INIS)

    Dyne, P.J.

    1976-01-01

    The Canadian geologic isolation program is directed at examining the potential of (1) salt deposits and (2) hard rock as repositories for radioactive wastes. It was felt essential from the inception that alternative host rocks be evaluated over a fairly large geographical area. The studies on salt deposits to date are based on existing geological information and have identified the areas that show some potential and merit further study. The factors considered include depth, thickness and purity of the deposit, overlying aquifers, and the potential for gas and oil exploration as well as potash recovery. The studies on hard rock are restricted to plutonic igneous rocks in the Ontario part of the Canadian Shield. Because geological information on their nature and extent is sparse, the study is limited to bodies that are well exposed and for which information is available.for which information is available. Field studies in the next two seasons are aimed at mapping the fault and joint patterns and defining the geologic controls on their development. In 1977 and 1978, two or three of the more favorable sites will be mapped in greater detail, and an exploratory drilling program will be established to determine the extent of fracturing at depth and the hydrology of these fractures. Conceptual designs of mined repositories in hard rock are also being made with the hope of identifying, at an early stage in this program, special problems in hard-rock repositories that may require development and study

  20. Hydro-chemical Characterization of Glacier Melt Water of Ponkar Glacier, Manang, Nepal.

    Science.gov (United States)

    Shrestha, R.; Sandeep, S.

    2017-12-01

    The study was carried out in Ponkar Glacier, representing Himalayan glacier of Nepal. The study aims in determining the physical-chemical properties of the glacier melt water. The sampling sites included moraine dammed, Ponkar Lake at 4100 m a.s.l to the downstream glaciated stream at 3580 m a.s.l. The water samples were collected from the seven different sites. Temperature was recorded by digital multi-thermometer on site. The samples were brought to the laboratory and the parameters were analyzed according to the APHA, AWWA and WEF standards. The glacier meltwater was slightly basic with pH 7.44 (±0.307). The meltwater was found to be in the range 30-60 which implies the water is moderately soft resulting value of concentration 36.429±8.664 mg CaCO3 L-1 and the electrical conductivity was found to be 47.14 (±11.18) µS/cm. The concentration of anion was in the order of HCO3 - > Cl- > SO42- > NO3- > TP-PO43- with the concentration 194.286±40.677, 55.707±30.265, 11.533±1.132 mgL-1, 1.00±0.7 mgL-1 and 0.514±0.32 mgL-1 respectively. Calcium carbonate weathering was found out to be the major source of dissolved ions in the region. The heavy metals were found in the order Al>Fe>Mn>Zn with concentration 1.34±0.648, 1.103±0.917, 0.08±0.028 and 0.023±0.004 mgL-1 respectively. The concentration of iron, manganese and zinc in some sites were below the detection limit. These results represent baseline data for the physical-chemical properties of the glacier meltwater

  1. Mendenhall Glacier Visitor Center vehicular and pedestrian traffic congestion study

    Science.gov (United States)

    2007-05-01

    The Mendenhall Glacier Visitor Center of Tongass National Forest in Juneau, Alaska is experiencing vehicular and pedestrian congestion. This study was initiated by the United States Forest Service, Alaska Region, in cooperation with Western Federal L...

  2. Glacier shrinkage and water resources in the Andes

    Science.gov (United States)

    Francou, Bernard; Coudrain, Anne

    For more than a century glaciers around the world have been melting as air temperatures rise due to a combination of natural processes and human activity. The disappearance of these glaciers can have wide-ranging effects, such as the creation of new natural hazards or changes in stream flow that could threaten water suppliesSome of the most dramatic melting has occurred in the Andes mountain range in South America. To highlight the climatic and glacial change in the Andes and to encourage the scientific community to strengthen the glacier observation network that stretches from Colombia to the Patagonian ice fields, the Instituto Nacional de Recursos Naturales (INRENA), Perú, and the Institute of Research and Development (IRD), France, recently organized the second Symposium on Mass Balance of Andean Glaciers in Huaráz,Perú.

  3. Glacier-influenced sedimentation on high-latitude continental margins

    National Research Council Canada - National Science Library

    Dowdeswell, J. A; Cofaigh, C. Ó

    2002-01-01

    This book examines the process and patterns of glacier-influenced sedimentation on high-latitude continental margins and the geophysical and geological signatures of the resulting sediments and landform...

  4. Discovering Chile's hidden water treasures – rock glaciers | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-05-30

    May 30, 2011 ... This means the research methods for investigating rock glaciers are ... group advising Chile's national environmental protection agency on ... Communities' perception of climate change risks in South America's Atlantic coasts.

  5. Rock glaciers, Fletschhorn Area, Valais, Switzerland, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a total amount of 74 rock glaciers which were investigated in the Fletschhorn Area in the southern Swiss Alps during the summer of 1995. The...

  6. Investigating cold based summit glaciers through direct access to the glacier base: a case study constraining the maximum age of Chli Titlis glacier, Switzerland

    Science.gov (United States)

    Bohleber, Pascal; Hoffmann, Helene; Kerch, Johanna; Sold, Leo; Fischer, Andrea

    2018-01-01

    Cold glaciers at the highest locations of the European Alps have been investigated by drilling ice cores to retrieve their stratigraphic climate records. Findings like the Oetztal ice man have demonstrated that small ice bodies at summit locations of comparatively lower altitudes may also contain old ice if locally frozen to the underlying bedrock. In this case, constraining the maximum age of their lowermost ice part may help to identify past periods with minimum ice extent in the Alps. However, with recent warming and consequent glacier mass loss, these sites may not preserve their unique climate information for much longer. Here we utilized an existing ice cave at Chli Titlis (3030 m), central Switzerland, to perform a case study for investigating the maximum age of cold-based summit glaciers in the Alps. The cave offers direct access to the glacier stratigraphy without the logistical effort required in ice core drilling. In addition, a pioneering exploration had already demonstrated stagnant cold ice conditions at Chli Titlis, albeit more than 25 years ago. Our englacial temperature measurements and the analysis of the isotopic and physical properties of ice blocks sampled at three locations within the ice cave show that cold ice still exists fairly unchanged today. State-of-the-art micro-radiocarbon analysis constrains the maximum age of the ice at Chli Titlis to about 5000 years before present. By this means, the approach presented here will contribute to a future systematic investigation of cold-based summit glaciers, also in the Eastern Alps.

  7. Neoglacial fluctuations of Deming Glacier, Mt. Baker, Washington USA.

    Science.gov (United States)

    Osborn, G.; Menounos, B.; Scott, K.; Clague, J. J.; Tucker, D.; Riedel, J.; Davis, P.

    2007-12-01

    Deming Glacier flows from the upper west slopes of Mt. Baker, a stratovolcano in the Cascade Range of Washington, USA. The north and south lateral moraines of Deming Glacier are composed of at least four tills separated by layers of detrital wood and sheared stumps in growth position. The stratigraphy records fluctuations of the glacier during the Holocene. The outer ten rings of an in situ stump from the middle wood layer, which is about 40 m below the north lateral moraine crest and 1.2 km downvalley from the present glacier terminus, yielded an age of 1750 ± 50~~ 14C yr BP [1810-1550 cal yr BP]. The stump revealed at least 300 rings and thus records a period of landscape stability and relatively restricted glaciation for several hundred years prior to ca. 1750 14C yr BP . Samples from the lowest wood layer also have been submitted for radiocarbon dating. Outer rings of detrital wood samples collected from two wood mats exposed in the south lateral moraine, 2.3 km downvalley of the glacier terminus, returned radiocarbon ages of 1600 ± 30~~ 14C yr BP [1550- 1410 cal yr BP] and 430 ± 30~~ 14C yr BP [AD 1420-1620]. These data indicate that Deming Glacier advanced over a vegetated moraine sometime after 1810 cal yr BP to a position less extensive that it achieved at the peak of the Little Ice Age. The glacier then receded before it began its final and most extensive Holocene advance after AD 1420. The older advance is correlative with the 'First Millennium AD' advance, recently recognized throughout western North America. The younger advance coincides with an advance of Mt. Baker's Easton Glacier [AD 1430-1630], and advances of many alpine glaciers elsewhere in western North America. Our data suggest that glaciers on Mt. Baker fluctuated in a similar manner to alpine glaciers in the Coast Mountains of British Columbia and in other mountain ranges of northwest North America during Neoglaciation.

  8. ROCKY PLANETESIMAL FORMATION VIA FLUFFY AGGREGATES OF NANOGRAINS

    Energy Technology Data Exchange (ETDEWEB)

    Arakawa, Sota; Nakamoto, Taishi, E-mail: arakawa.s.ac@m.titech.ac.jp [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Meguro, Tokyo 152-8551 (Japan)

    2016-12-01

    Several pieces of evidence suggest that silicate grains in primitive meteorites are not interstellar grains but condensates formed in the early solar system. Moreover, the size distribution of matrix grains in chondrites implies that these condensates might be formed as nanometer-sized grains. Therefore, we propose a novel scenario for rocky planetesimal formation in which nanometer-sized silicate grains are produced by evaporation and recondensation events in early solar nebula, and rocky planetesimals are formed via aggregation of these nanograins. We reveal that silicate nanograins can grow into rocky planetesimals via direct aggregation without catastrophic fragmentation and serious radial drift, and our results provide a suitable condition for protoplanet formation in our solar system.

  9. The rocky flats controversy on radionuclide soil action levels

    International Nuclear Information System (INIS)

    Earle, T.C.

    2004-01-01

    This report describes the Rocky Flats radionuclide soil action level controversy as a case study for the purpose of understanding the nature and value of stakeholder involvement in the management of radiological hazards. The report consists of three main sections. The first section outlines the Rocky Flats story, including the Cold War era, the post-Cold War era, and the transition between the two. This provides the context necessary to understand the radionuclide soil action level controversy, the main events of which are described in the second section. In the final section, the Rocky Flats case is briefly discussed within the framework of a general model of stakeholder involvement and the lessons learned from the case are identified. (author)

  10. Kawasaki disease following Rocky Mountain spotted fever: a case report

    Directory of Open Access Journals (Sweden)

    Bal Aswine K

    2009-07-01

    Full Text Available Abstract Introduction Kawasaki disease is an idiopathic acute systemic vasculitis of childhood. Although it simulates the clinical features of many infectious diseases, an infectious etiology has not been established. This is the first reported case of Kawasaki disease following Rocky Mountain spotted fever. Case presentation We report the case of a 4-year-old girl who presented with fever and petechial rash. Serology confirmed Rocky Mountain spotted fever. While being treated with intravenous doxycycline, she developed swelling of her hands and feet. She had the clinical features of Kawasaki disease which resolved after therapy with intravenous immune globulin (IVIG and aspirin. Conclusion This case report suggests that Kawasaki disease can occur concurrently or immediately after a rickettsial illness such as Rocky Mountain spotted fever, hypothesizing an antigen-driven immune response to a rickettsial antigen.

  11. Kawasaki disease following Rocky Mountain spotted fever: a case report.

    Science.gov (United States)

    Bal, Aswine K; Kairys, Steven W

    2009-07-06

    Kawasaki disease is an idiopathic acute systemic vasculitis of childhood. Although it simulates the clinical features of many infectious diseases, an infectious etiology has not been established. This is the first reported case of Kawasaki disease following Rocky Mountain spotted fever. We report the case of a 4-year-old girl who presented with fever and petechial rash. Serology confirmed Rocky Mountain spotted fever. While being treated with intravenous doxycycline, she developed swelling of her hands and feet. She had the clinical features of Kawasaki disease which resolved after therapy with intravenous immune globulin (IVIG) and aspirin. This case report suggests that Kawasaki disease can occur concurrently or immediately after a rickettsial illness such as Rocky Mountain spotted fever, hypothesizing an antigen-driven immune response to a rickettsial antigen.

  12. Canadian attitudes to nuclear power

    International Nuclear Information System (INIS)

    Davies, J.E.O.

    1977-01-01

    In the past ten years, public interest in nuclear power and its relationship to the environment has grown. Although most Canadians have accepted nuclear power as a means of generating electricity, there is significant opposition to its use. This opposition has effectively forced the Canadian nuclear industry to modify its behaviour to the public in the face of growing concern over the safety of nuclear power and related matters. The paper reviews Canadian experience concerning public acceptance of nuclear power, with special reference to the public information activities of the Canadian nuclear industry. Experience has shown the need for scientific social data that will permit the nuclear industry to involve the public in a rational examination of its concern about nuclear power. The Canadian Nuclear Association sponsored such studies in 1976 and the findings are discussed. They consisted of a national assessment of public attitudes, two regional studies and a study of Canadian policy-makers' views on nuclear energy. The social data obtained were of a base-line nature describing Canadian perceptions of and attitudes to nuclear power at that time. This research established that Canadian levels of knowledge about nuclear power are very low and that there are marked regional differences. Only 56% of the population have the minimum knowledge required to indicate that they know that nuclear power can be used to generate electricity. Nevertheless, 21% of informed Canadians oppose nuclear power primarily on the grounds that it is not safe. Radiation and waste management are seen to be major disadvantages. In perspective, Canadians are more concerned with inflation than with the energy supply. About half of all Canadians see the question of energy supplies as a future problem (within five years), not a present one. A more important aspect of energy is seen by the majority of Canadians to be some form of energy independence. The use of data from these studies is no easy

  13. Canadian beef quality audit.

    Science.gov (United States)

    Van Donkersgoed, J; Jewison, G; Mann, M; Cherry, B; Altwasser, B; Lower, R; Wiggins, K; Dejonge, R; Thorlakson, B; Moss, E; Mills, C; Grogan, H

    1997-01-01

    A study was conducted in 4 Canadian processing plants in 1995-96 to determine the prevalence of quality defects in Canadian cattle. One percent of the annual number of cattle processed in Canada were evaluated on the processing floor and 0.1% were graded in the cooler. Brands were observed on 37% and multiple brands on 6% of the cattle. Forty percent of the cattle had horns, 20% of which were scurs, 33% were stubs, 10% were tipped, and 37% were full length. Tag (mud and manure on the hide) was observed on 34% of the cattle. Bruises were found on 78% of the carcasses, 81% of which were minor in severity. Fifteen percent of the bruises were located on the round, 29% on the loin, 40% on the rib, 16% on the chuck, and 0.02% on the brisket. Grubs were observed in 0.02% of the steers, and injection sites were observed in 1.3% of whole hanging carcasses. Seventy percent of the livers were passed for human food and 14% for pet food; 16% were condemned. Approximately 71% of the liver condemnations were due to liver abscesses. Four percent of the heads, 6% of the tongues, and 0.2% of whole carcasses were condemned. The pregnancy rate in female cattle was approximately 6.7%. The average hot carcass weight was 357 kg (s = 40) in steers, 325 kg (s = 41) in heifers, 305 kg (s = 53) in cows, 388 kg (s = 62) in virgin bulls and 340 kg (s = 39) in mature bulls. The average ribeye area in all cattle was 84 cm2 (s = 12); range 29 cm2 to 128 cm2. Grade fat was highly variable and averaged 9 mm (s = 4) for steers and heifers, 6 mm (s = 6) for cows, 5 mm (s = 1) for virgin bulls, and 4 mm (s = 0.5) for mature bulls. The average lean meat yield was 59.7% in cattle (s = 3.4); range 39% to 67%. One percent of the carcasses were devoid of marbling, 1% were dark cutters, and 0.05% of the steer carcasses were staggy. Six percent of the carcasses had poor conformation, 3.7% were underfinished, and 0.7% were overfinished. Yellow fat was observed in 4% of the carcasses; 10% of carcasses were

  14. Rock glaciers in the Suntar‑Khayata Range

    Directory of Open Access Journals (Sweden)

    V. M. Lytkin

    2016-01-01

    Full Text Available The remote map‑making technique and results of field investigations made possible for the first time to reveal a great number of rock glaciers within the area of the Suntar‑Khayata Range (North‑East Asia. A total of 540 formations were identified. Among them, 47 rock glaciers were classified as corrie (cirque tongue‑shaped formations and 493 ones – as niche lobe‑shaped (single‑ and multi‑lobe rock glaciers. Occurrence of such formations is 8.4/100 km2, that is the largest in the North‑East Asia. The rock glaciers in this region are found within a range of true altitudes from 1297 up to 2402 m asl. The majority of active features, however, are confined to the interval between 1500 and 1900 m asl. Rock glaciers occur in the altitudinal range of 1297 to 2402 m asl. The majority of active features, however, are confined to the interval between 1500 and 1900 m asl, and the main part of active formations is located within the range of 1500‑2500 m. The frequency analysis of true altitudes of the rock‑glacier occurrence indicates that their formation can be caused by the hypsometry of the region relation to morphoclimatic zonality.

  15. Tropical New World Glacier Recession from the mid-1980s to the mid-2000s

    Science.gov (United States)

    Slayback, D. A.; Tucker, C. J.

    2010-12-01

    We report on the systematic retreat of all glaciers in the tropics of the New World from the mid-1980s to the mid-2000s. These glaciers comprise 99% of the world’s tropical glaciers and occur in Bolivia, Peru, Ecuador, Colombia, Venezuela, and Mexico. It was necessary to use a large quantity of Landsat satellite data (124 images), selecting multiple images for every glacier for both epochs, to minimize confusion of glacier area with snow. Change in glacier extent was combined with a digital elevation model (DEM) to provide information on the elevation and aspect of areas of glacier recession. Overall, we found glacier recession of approximately 30% over twenty years, declining from ~2500 km2 from the mid-1980s to ~1800 km2 in the mid-2000s. In addition, there was a strong association of glacier recession with elevation and aspect. We discuss these trends in relation to hypothesized climatic influences.

  16. Glaciers and hydrological changes in the Tien Shan: simulation and prediction

    International Nuclear Information System (INIS)

    Aizen, V B; Aizen, E M; Kuzmichonok, V A

    2007-01-01

    In this study, we estimated the current glacier state and forecast the potential impact of global and regional climate change on the glaciers and glacier runoff in the Tien Shan. General (G) and detailed (D) simulations were developed based on assessment of the Tien Shan glacier recession between 1943 and 2003 using an iterative stepwise increase in the equilibrium line altitude of 20 m. The G simulation was developed for 2777 grids each of which covered over 1000 km 2 of glacier surface and D for the 15 953 Tien Shan glaciers. Both simulations employed glacier morphometric characteristics derived from Digital Elevation Model based on remote sensing data, high resolution maps and in situ GPS validation. Simulated changes in glacier area demonstrated that a possible increase in air temperature of 1 deg. C at E-barLA must be compensated by a 100 mm increase in precipitation at the same altitude if Tien Shan glaciers are to be maintained in their current state. An increase in mean air temperature of 4 deg. C and precipitation of 1.1 times the current level could increase E-barLA by 570 m during the 21st century. Under these conditions, the number of glaciers, glacier covered area, glacier volume, and glacier runoff are predicted to be 94%, 69%, 75%, and 75% of current values. The maximum glacier runoff may reach as much as 1.25 times current levels while the minimum will likely equal zero

  17. The removal of plutonium contaminants from Rocky Flats Plant soil

    International Nuclear Information System (INIS)

    Sunderland, N.R.

    1987-01-01

    This research was undertaken to determine if the TRUclean process could effectively remove radioactive elements from soils other than derived coral. This is an interim report prior to the project report and discusses the outcome of the tests of the Rocky Flats Plant (RFP) soil. The soil tested contained plutonium particulates in the micron and submicron range. Volume reduction and activity removal were accomplished with an overall efficiency of greater than 90%. The TRUclean process is a very practical and economical solution to soil contamination problems at the Rocky Flats Plant

  18. Benchmarking and Performance Improvement at Rocky Flats Environmental Technology Site

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, C. [Kaiser-Hill Co., LLC, Golden, CO (United States)], Doyle, D. [USDOE Rocky Flats Office, Golden, CO (United States)], Featherman, W.D. [Project Performance Corp., Sterline, VA (United States)

    1997-12-31

    The Rocky Flats Environmental Technology Site (RFETS) has initiated a major work process improvement campaign using the tools of formalized benchmarking and streamlining. This paper provides insights into some of the process improvement activities performed at Rocky Flats from November 1995 through December 1996. It reviews the background, motivation, methodology, results, and lessons learned from this ongoing effort. The paper also presents important gains realized through process analysis and improvement including significant cost savings, productivity improvements, and an enhanced understanding of site work processes.

  19. Canadian wind energy program

    Energy Technology Data Exchange (ETDEWEB)

    Templin, R J; South, P

    1976-01-01

    Several aspects of recent work at the National Research Council of Canada on the development of vertical-axis turbines have been reviewed. Most of this work, during the past year or more, has been in support of the design of a 200 kW unit now being built for experimental operation on the Magdelen Islands in the Gulf of St. Lawrence. Results of small and large scale aeroelastic wind tunnel model experiments have confirmed that very large scale vertical-axis wind turbines are feasible, especially if designed for normal operation at constant rotational speed. A computer model of a simple mixed power system has indicated that substantial cost savings may be possible by using wind energy in Canadian east coast regions. 4 refs., 11 figs., 1 tab.

  20. Seasonal and altitudinal variations in snow algal communities on an Alaskan glacier (Gulkana glacier in the Alaska range)

    International Nuclear Information System (INIS)

    Takeuchi, Nozomu

    2013-01-01

    Snow and ice algae are cold tolerant algae growing on the surface of snow and ice, and they play an important role in the carbon cycles for glaciers and snowfields in the world. Seasonal and altitudinal variations in seven major taxa of algae (green algae and cyanobacteria) were investigated on the Gulkana glacier in Alaska at six different elevations from May to September in 2001. The snow algal communities and their biomasses changed over time and elevation. Snow algae were rarely observed on the glacier in May although air temperature had been above 0 ° C since the middle of the month and surface snow had melted. In June, algae appeared in the lower areas of the glacier, where the ablation ice surface was exposed. In August, the distribution of algae was extended to the upper parts of the glacier as the snow line was elevated. In September, the glacier surface was finally covered with new winter snow, which terminated algal growth in the season. Mean algal biomass of the study sites continuously increased and reached 6.3 × 10 μl m −2 in cell volume or 13 mg carbon m −2 in September. The algal community was dominated by Chlamydomonas nivalis on the snow surface, and by Ancylonema nordenskiöldii and Mesotaenium berggrenii on the ice surface throughout the melting season. Other algae were less abundant and appeared in only a limited area of the glacier. Results in this study suggest that algae on both snow and ice surfaces significantly contribute to the net production of organic carbon on the glacier and substantially affect surface albedo of the snow and ice during the melting season. (letter)

  1. Recent glacier mass balance and area changes in the Kangri Karpo Mountains from DEMs and glacier inventories

    Directory of Open Access Journals (Sweden)

    K. Wu

    2018-01-01

    Full Text Available Due to the influence of the Indian monsoon, the Kangri Karpo Mountains in the south-east of the Tibetan Plateau is in the most humid and one of the most important and concentrated regions containing maritime (temperate glaciers. Glacier mass loss in the Kangri Karpo is an important contributor to global mean sea level rise, and changes run-off distribution, increasing the risk of glacial-lake outburst floods (GLOFs. Because of its inaccessibility and high labour costs, information about the Kangri Karpo glaciers is still limited. Using geodetic methods based on digital elevation models (DEMs derived from 1980 topographic maps from the Shuttle Radar Topography Mission (SRTM (2000 and from TerraSAR-X/TanDEM-X (2014, this study has determined glacier elevation changes. Glacier area and length changes between 1980 and 2015 were derived from topographical maps and Landsat TM/ETM+/OLI images. Results show that the Kangri Karpo contained 1166 glaciers with an area of 2048.50 ± 48.65 km2 in 2015. Ice cover diminished by 679.51 ± 59.49 km2 (24.9 ± 2.2 % or 0.71 ± 0.06 % a−1 from 1980 to 2015, although nine glaciers advanced. A glacierized area of 788.28 km2, derived from DEM differencing, experienced a mean mass loss of 0.46 ± 0.08 m w.e. a−1 from 1980 to 2014. Shrinkage and mass loss accelerated significantly from 2000 to 2015 compared to 1980–2000, consistent with a warming climate.

  2. Recent glacier mass balance and area changes in the Kangri Karpo Mountains from DEMs and glacier inventories

    Science.gov (United States)

    Wu, Kunpeng; Liu, Shiyin; Jiang, Zongli; Xu, Junli; Wei, Junfeng; Guo, Wanqin

    2018-01-01

    Due to the influence of the Indian monsoon, the Kangri Karpo Mountains in the south-east of the Tibetan Plateau is in the most humid and one of the most important and concentrated regions containing maritime (temperate) glaciers. Glacier mass loss in the Kangri Karpo is an important contributor to global mean sea level rise, and changes run-off distribution, increasing the risk of glacial-lake outburst floods (GLOFs). Because of its inaccessibility and high labour costs, information about the Kangri Karpo glaciers is still limited. Using geodetic methods based on digital elevation models (DEMs) derived from 1980 topographic maps from the Shuttle Radar Topography Mission (SRTM) (2000) and from TerraSAR-X/TanDEM-X (2014), this study has determined glacier elevation changes. Glacier area and length changes between 1980 and 2015 were derived from topographical maps and Landsat TM/ETM+/OLI images. Results show that the Kangri Karpo contained 1166 glaciers with an area of 2048.50 ± 48.65 km2 in 2015. Ice cover diminished by 679.51 ± 59.49 km2 (24.9 ± 2.2 %) or 0.71 ± 0.06 % a-1 from 1980 to 2015, although nine glaciers advanced. A glacierized area of 788.28 km2, derived from DEM differencing, experienced a mean mass loss of 0.46 ± 0.08 m w.e. a-1 from 1980 to 2014. Shrinkage and mass loss accelerated significantly from 2000 to 2015 compared to 1980-2000, consistent with a warming climate.

  3. Dictionaries of Canadian English | Considine | Lexikos

    African Journals Online (AJOL)

    ... its best, reached a high degree of sophistication, there are still major opportunities waiting to be taken. keywords: dictionary, lexicography, canadian english, canadianisms, national dictionaries, canadian french, canadian first nations lan-guages, bilingual dictionaries, regional dictionaries, unfinished diction-ary projects ...

  4. Glacier dynamics over the last quarter of a century at Helheim, Kangerdlugssuaq and 14 other major Greenland outlet glaciers

    Directory of Open Access Journals (Sweden)

    S. L. Bevan

    2012-09-01

    Full Text Available The Greenland ice sheet is experiencing increasing rates of mass loss, the majority of which results from changes in discharge from tidewater glaciers. Both atmospheric and ocean drivers have been implicated in these dynamic changes, but understanding the nature of the response has been hampered by the lack of measurements of glacier flow rates predating the recent period of warming. Here, using Landsat-5 data from 1985 onwards, we extend back in time the record of surface velocities and ice-front position for 16 of Greenland's fastest-flowing tidewater glaciers, and compare these to more recent data from Landsat-7 and satellite-borne synthetic-aperture radar. Climate re-analysis data and sea surface temperatures from 1982 show that since 1995 most of Greenland and its surrounding oceans have experienced significant overall warming, and a switch to a warming trend. During the period from 1985 to 1995 when Greenland and the surrounding oceans were not warming, major tidewater outlet glaciers around Greenland, including Kangerdlugssuaq and Helheim, were dynamically stable. Since the mid-1990s, glacier discharge has consistently been both greater and more variable. Together, these observations support the hypothesis that recent dynamic change is a rapid response to climate forcing. Both air and ocean temperatures in this region are predicted to continue to warm, and will therefore likely drive further change in outlet glacier discharge.

  5. Bathymetry of Torssukatak fjord and one century of glacier stability

    Science.gov (United States)

    An, L.; Rignot, E. J.; Morlighem, M.

    2017-12-01

    Marine-terminating glaciers dominate the evolution of the Greenland Ice Sheet(GrIS) mass balance as they control 90% of the ice discharge into the ocean. Warm air temperatures thin the glaciers from the top to unground ice fronts from the bed. Warm oceans erode the submerged grounded ice, causing the grounding line to retreat. To interpret the recent and future evolution of two outlet glaciers, Sermeq Avangnardleq (AVA) and Sermeq Kujatdleq (KUJ) in central West Greenland, flowing into the ice-choked Torssukatak fjord (TOR), we need to know their ice thickness and bed topography and the fjord bathymetry. Here, we present a novel mapping of the glacier bed topography, ice thickness and sea floor bathymetry near the grounding line using high resolution airborne gravity data from AIRGrav collected in August 2012 with a helicopter platform, at 500 m spacing grid, 50 knots ground speed, 80 m ground clearance, with submilligal accuracy, i.e. higher than NASA Operation IceBridge (OIB)'s 5.2 km resolution, 290 knots, and 450 m clearance. We also employ MultiBeam Echo Sounding data (MBES) collected in the fjord since 2009. We had to wait until the summer of 2016, during Ocean Melting Greenland (OMG), to map the fjord bathymetry near the ice fronts for the first time. We constrain the 3D inversion of the gravity data with MBES in the fjord and a reconstruction of the glacier bed topography using mass conservation (MC) on land ice. The seamless topography obtained across the grounding line reveal the presence of a 300-m sill for AVA, which explains why this glacier has been stable for a century, despite changes in surface melt and ocean-induced melt and the presence of a deep fjord (800 m) in front of the glacier. For KUJ, we also reveal the presence of a wide sill (300 m depth) near the current ice front which explains its stability and the stranding of iceberg debris in front of the glacier. The results shed new light on the evolution of these glaciers and explain their

  6. Exploring the mobility of cryoconite on High-Arctic glaciers

    Science.gov (United States)

    Irvine-Fynn, T. D.; Hodson, A. J.; Bridge, J. W.; Langford, H.; Anesio, A.; Ohlanders, N.; Newton, S.

    2010-12-01

    There has been a growing awareness of the significance of biologically active dust (cryoconite) on the energy balance of, and nutrient cycling at glacier surfaces. Moreover, researchers have estimated the mass of biological material released from glacier ice to downstream environments and ecosystems, including the melt-out of cells from emergent ice in the ablation area. However, the processes, rates and mechanisms of cryoconite mobility and transport have not been fully explored. For many smaller valley glaciers in the High-Arctic, the climate dictates only a thin (~ 1m) layer of ice at the glacier surface is at the melting point during the summer months. This surface ice is commonly characterized by an increased porosity in response to incident energy and hydraulic conditions, and has been termed the “weathering crust”. The presence of cryoconite, with its higher radiation absorption, exacerbates the weathering crust development. Thus, crucially, the transport of cryoconite is not confined to simply a ‘smooth’ ice surface, but rather also includes mobility in the near-surface ice matrix. Here, we present initial results from investigations of cryoconite transport at Midtre Lovénbreen and Longyearbreen, two north-facing valley glaciers in Svalbard (Norway). Using time-lapse imagery, we explore the transport rates of cryoconite on a glacier surface and consider the associations between mobility and meteorological conditions. Results suggest some disparity between micro-, local- and plot-scale observations of cryoconite transport: the differences imply controlling influences of cryoconite volume, ice surface topography and ice structure. While to examine the relative volumes of cryoconite exported from the glacier surface by supraglacial streams we employ flow cytometry, using SYBR-Green-II staining to identify the biological component of the suspended load. Preliminary comparisons between shallow (1m) ice cores and in-stream concentrations suggest

  7. Mass balance model parameter transferability on a tropical glacier

    Science.gov (United States)

    Gurgiser, Wolfgang; Mölg, Thomas; Nicholson, Lindsey; Kaser, Georg

    2013-04-01

    The mass balance and melt water production of glaciers is of particular interest in the Peruvian Andes where glacier melt water has markedly increased water supply during the pronounced dry seasons in recent decades. However, the melt water contribution from glaciers is projected to decrease with appreciable negative impacts on the local society within the coming decades. Understanding mass balance processes on tropical glaciers is a prerequisite for modeling present and future glacier runoff. As a first step towards this aim we applied a process-based surface mass balance model in order to calculate observed ablation at two stakes in the ablation zone of Shallap Glacier (4800 m a.s.l., 9°S) in the Cordillera Blanca, Peru. Under the tropical climate, the snow line migrates very frequently across most of the ablation zone all year round causing large temporal and spatial variations of glacier surface conditions and related ablation. Consequently, pronounced differences between the two chosen stakes and the two years were observed. Hourly records of temperature, humidity, wind speed, short wave incoming radiation, and precipitation are available from an automatic weather station (AWS) on the moraine near the glacier for the hydrological years 2006/07 and 2007/08 while stake readings are available at intervals of between 14 to 64 days. To optimize model parameters, we used 1000 model simulations in which the most sensitive model parameters were varied randomly within their physically meaningful ranges. The modeled surface height change was evaluated against the two stake locations in the lower ablation zone (SH11, 4760m) and in the upper ablation zone (SH22, 4816m), respectively. The optimal parameter set for each point achieved good model skill but if we transfer the best parameter combination from one stake site to the other stake site model errors increases significantly. The same happens if we optimize the model parameters for each year individually and transfer

  8. Distributed ice thickness and glacier volume in southern South America

    Science.gov (United States)

    Carrivick, Jonathan L.; Davies, Bethan J.; James, William H. M.; Quincey, Duncan J.; Glasser, Neil F.

    2016-11-01

    South American glaciers, including those in Patagonia, presently contribute the largest amount of meltwater to sea level rise per unit glacier area in the world. Yet understanding of the mechanisms behind the associated glacier mass balance changes remains unquantified partly because models are hindered by a lack of knowledge of subglacial topography. This study applied a perfect-plasticity model along glacier centre-lines to derive a first-order estimate of ice thickness and then interpolated these thickness estimates across glacier areas. This produced the first complete coverage of distributed ice thickness, bed topography and volume for 617 glaciers between 41°S and 55°S and in 24 major glacier regions. Maximum modelled ice thicknesses reach 1631 m ± 179 m in the South Patagonian Icefield (SPI), 1315 m ± 145 m in the North Patagonian Icefield (NPI) and 936 m ± 103 m in Cordillera Darwin. The total modelled volume of ice is 1234.6 km3 ± 246.8 km3 for the NPI, 4326.6 km3 ± 865.2 km3 for the SPI and 151.9 km3 ± 30.38 km3 for Cordillera Darwin. The total volume was modelled to be 5955 km3 ± 1191 km3, which equates to 5458.3 Gt ± 1091.6 Gt ice and to 15.08 mm ± 3.01 mm sea level equivalent (SLE). However, a total area of 655 km2 contains ice below sea level and there are 282 individual overdeepenings with a mean depth of 38 m and a total volume if filled with water to the brim of 102 km3. Adjusting the potential SLE for the ice volume below sea level and for the maximum potential storage of meltwater in these overdeepenings produces a maximum potential sea level rise (SLR) of 14.71 mm ± 2.94 mm. We provide a calculation of the present ice volume per major river catchment and we discuss likely changes to southern South America glaciers in the future. The ice thickness and subglacial topography modelled by this study will facilitate future studies of ice dynamics and glacier isostatic adjustment, and will be important for projecting water resources and

  9. Simulating calving-front changes of Greenland’s marine-terminating glaciers

    DEFF Research Database (Denmark)

    Haubner, Konstanze

    glacier retreat to a certain degree and foremost define the variation of retreat rates. The thesis implies the importance of incorporating glacier-front dynamics into ice sheet models in order to match observations and verifies atmospheric and oceanic forcing as important triggers for glacier retreat...... UI outlet glaciers. The change in mass flux resulting from the prescribed glacier retreat contributes to 70% of UI’s mass change over the simulation periods. The residual mass change is due to surface mass balance. A second simulation on the fastest UI glacier (UI-1) reveals that frontal melt rates...

  10. The Canadian Dollar and the Dutch and Canadian Diseases

    Directory of Open Access Journals (Sweden)

    Serge Coulombe

    2013-10-01

    Full Text Available With the spectacular rise of the dollar, along with rising natural-resource prices during the first decade of the 21st century, Canadians heard a great deal about Dutch disease. Many politicians and pundits blamed the phenomenon — in which a country’s currency, inflated by rising commodity prices, renders manufacturing exports increasingly uncompetitive — for rising unemployment in the Canadian manufacturing industry. But a close look at what happened during that period reveals that the Dutch disease mechanism was only part of the story. The other part, and quantitatively the most important, is an affliction of an altogether different providence: Canadian disease. Canadian disease is the economic trouble that can be caused by Canada’s extraordinarily heavy reliance on the United States as a trading partner. As a consequence, a sudden depreciation of the U.S, dollar will deteriorate the competitiveness of Canadian manufacturing exporters. Such a phenomenon was at work during the “Great Appreciation” of the Canadian dollar between 2002 and 2008 — the largest such appreciation on record in this country. The depreciation of the U.S. dollar is a phenomenon that is independent of the resource boom and the resulting consequences on the Canadian economy cannot be endorsed to a Dutch disease. Almost 2/3 of the employment losses that are exchange rate related in the trade-exposed manufacturers in Canada during the 2002–2008 period could be attributed to the Canadian disease. The Canadian dollar is partly driven by commodity prices, and the appreciation of the Canadian dollar exerts a negative impact on manufacturing industries that are exposed to international competition. This phenomenon can be coined as a Dutch Affair. The Dutch Affair becomes a disease in the long run when the non-renewable resource is depleted and the manufacturing base is gone. New manufacturing activities might not reappear due to a variety of obstacles. In Canada

  11. Engendering migrant health: Canadian perspectives

    National Research Council Canada - National Science Library

    Spitzer, Denise L

    2011-01-01

    "Voluntary migrants to Canada are generally healthier than the average Canadian, but after ten years in the country they report poorer health and higher rates of chronic disease than those born here...

  12. Engendering migrant health: Canadian perspectives

    National Research Council Canada - National Science Library

    Spitzer, Denise L

    2011-01-01

    .... What contributes to this deterioration, and how can its effects be mitigated? Engendering Migrant Health brings together researchers from across Canada to address the intersections of gender, immigration, and health in the lives of new Canadians...

  13. The Canadian heavy water situation

    International Nuclear Information System (INIS)

    Dahlinger, A.

    The Canadian heavy water industry is analyzed. Supply and demand are predicted through 1985. Pricing is broken down into components. Backup R and D contributes greatly to process improvements. (E.C.B.)

  14. Canadian gas supply : an update

    International Nuclear Information System (INIS)

    Rochefort, T.

    1998-01-01

    An overview of the daily production from the Western Canada Sedimentary Basin (WCSB) from 1986 to 1997 was presented. This presentation also outlined Canadian production trends, Canadian reserves and resources, and supply challenges. Ultimate conventional marketable gas from the WCSB, the Scotian Shelf, the Beaufort Sea and Canada's Arctic region was estimated at 591 TCF. Issues regarding supply and demand of natural gas such as the impact of electricity restructuring on pricing, generation fuel mix, the capacity of the U.S. market to absorb Canadian heavy oil production, and the influence of the rate of technological advances on supply and demand were outlined. The overall conclusion confirmed the health and competitiveness of the Canadian upstream sector and expressed confidence that the WCSB can support rising levels of production to meet the expected continued market growth. tabs., figs

  15. Application of a minimal glacier model to Hansbreen, Svalbard

    Directory of Open Access Journals (Sweden)

    J. Oerlemans

    2011-01-01

    Full Text Available Hansbreen is a well studied tidewater glacier in the southwestern part of Svalbard, currently about 16 km long. Since the end of the 19th century it has been retreating over a distance of 2.7 km. In this paper the global dynamics of Hansbreen are studied with a minimal glacier model, in which the ice mechanics are strongly parameterised and a simple law for iceberg calving is used. The model is calibrated by reconstructing a climate history in such a way that observed and simulated glacier length match. In addition, the calving law is tuned to reproduce the observed mean calving flux for the period 2000–2008.

    Equilibrium states are studied for a wide range of values of the equilibrium line altitude. The dynamics of the glacier are strongly nonlinear. The height-mass balance feedback and the water depth-calving flux feedback give rise to cusp catastrophes in the system.

    For the present climatic conditions Hansbreen cannot survive. Depending on the imposed climate change scenario, in AD 2100 Hansbreen is predicted to have a length between 10 and 12 km. The corresponding decrease in ice volume (relative to the volume in AD 2000 is 45 to 65%.

    Finally the late-Holocene history of Hansbreen is considered. We quote evidence from dated peat samples that Hansbreen did not exist during the Holocene Climatic Optimum. We speculate that at the end of the mid-Holocene Climatic Optimum Hansbreen could advance because the glacier bed was at least 50 m higher than today, and because the tributary glaciers on the western side may have supplied a significant amount of mass to the main stream. The excavation of the overdeepening and the formation of the shoal at the glacier terminus probably took place during the Little Ice Age.

  16. Recent glacier retreat and climate trends in Cordillera Huaytapallana, Peru

    Science.gov (United States)

    López-Moreno, J. I.; Fontaneda, S.; Bazo, J.; Revuelto, J.; Azorin-Molina, C.; Valero-Garcés, B.; Morán-Tejeda, E.; Vicente-Serrano, S. M.; Zubieta, R.; Alejo-Cochachín, J.

    2014-01-01

    We analyzed 19 annual Landsat Thematic Mapper images from 1984 to 2011 to determine changes of the glaciated surface and snow line elevation in six mountain areas of the Cordillera Huaytapallana range in Peru. In contrast to other Peruvian mountains, glacier retreat in these mountains has been poorly documented, even though this is a heavily glaciated area. These glaciers are the main source of water for the surrounding lowlands, and melting of these glaciers has triggered several outburst floods. During the 28-year study period, there was a 55% decrease in the surface covered by glaciers and the snowline moved upward in different regions by 93 to 157 m. Moreover, several new lakes formed in the recently deglaciated areas. There was an increase in precipitation during the wet season (October-April) over the 28-year study period. The significant increase in maximum temperatures may be related to the significant glacier retreat in the study area. There were significant differences in the wet season temperatures during El Niño (warmer) and La Niña (colder) years. Although La Niña years were generally more humid than El Niño years, these differences were not statistically significant. Thus, glaciers tended to retreat at a high rate during El Niño years, but tended to be stable or increase during La Niña years, although there were some notable deviations from this general pattern. Climate simulations for 2021 to 2050, based on the most optimistic assumptions of greenhouse gas concentrations, forecast a continuation of climate warming at the same rate as documented here. Such changes in temperature might lead to a critical situation for the glaciers of the Cordillera Huaytapallana, and may significantly impact the water resources, ecology, and natural hazards of the surrounding areas.

  17. Reconstruction of Equilibrium Line Altitudes of Nevado Coropuna Glaciers (Southern Peru) from the Late Pleistocene to the present

    Science.gov (United States)

    Úbeda, J.; Palacios, D.; Vázquez, L.

    2009-04-01

    automatic functions within the GIS operating environment. To reconstruct the ELAs of the glaciers, the Area x Altitude Balance Ratio (AABR) method was used. This method is extensively described in Osmaston (2005). To determine the rates of deglaciation, variations observed for 2007 in surface areas and ELAs against their values in 1986, 1955 and the Little Ice Age (LIA) were used as geoindicators. Establishing deglaciation rates has allowed forecasts to be made as to when the complete disappearance of ice mass could occur for three future scenarios, considering the hypothetical reproduction in each scenario of the rates of deglaciation observed since 1986 (Scenario 1), 1955 (Scenario 2) and the LIA (Scenario 3). To determine the chronology of the last maximum advance of the glaciers and the last volcanic manifestations, samples were taken from moraine blocks and glaciated rocky thresholds, and also from lava ejected during the last eruption, in the eastern sector of the complex. Due to their recent external appearance, since they have been channeled by glacial valleys and have been affected by ice masses only at the head, these lavas had been dated as Holocene. Absolute dating was performed using cosmogenic methods (Cl36). As a result of applying the proposed method, glacial system surface areas have been estimated for 2007 (47 km2), 1986 (54 km2) and 1955 (56 km2), implying a reduction of ~18% in 52 years. The process appears to have speeded up in the last decades (~13% in only 21 years). Surfaces were also estimated and ELAs reconstructed for the NE and SE groups in 2007, 1986, 1955, the Little Ice Age and during the last maximum advance. Glaciers from the NE group show an area during all periods (2.3, 2.7, 2.9, 3.3 and 30 km2) smaller than SE group glaciers (8.1, 9.9, 10.3, 11.9 and 66.5 km2). An individual analysis of glaciers in the NE and SE groups in 2007 shows a reduction in surface area two to four times greater than that observed between 1955 and 1986. ELAs are

  18. Rocky Flats Cleanup Agreement implementation successes and challenges

    International Nuclear Information System (INIS)

    Shelton, D.C.

    1997-01-01

    On July 19, 1996 the US Department of Energy (DOE), State of Colorado (CDPHE), and US Environmental Protection Agency (EPA) entered into an agreement called the Rocky Flats Cleanup Agreement (RFCA) for the cleanup and closure of the Rocky Flats Environmental Technology Site (RFETS or Rocky Flats). Major elements of the agreement include: an Integrated Site-Wide Baseline; up to twelve significant enforceable milestones per year; agreed upon soil and water action levels and standards for cleanup; open space as the likely foreseeable land use; the plutonium and TRU waste removed by 2015; streamlined regulatory process; agreement with the Defense Nuclear Facilities Safety Board (DNFSB) to coordinate activities; and a risk reduction focus. Successful implementation of RFCA requires a substantial effort by the parties to change their way of thinking about RFETS and meet the deliverables and commitments. Substantial progress toward Site closure through the implementation of RFCA has been accomplished in the short time since the signing, yet much remains to be done. Much can be learned from the Rocky Flats experience by other facilities in similar situations

  19. Rocky Flats Plant Site Environmental Report for 1992

    International Nuclear Information System (INIS)

    Cirrincione, D.A.; Erdmann, N.L.

    1992-01-01

    The Rocky Rats Plant Site Environmental Report provides summary information on the plant's environmental monitoring programs and the results recorded during 1992. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population

  20. Public involvement in cleanup - the Rocky Flats experience

    International Nuclear Information System (INIS)

    Paukert, J.; Pennock, S.; Schassburger, R.

    1992-01-01

    The U.S. Department of Energy's Rocky Flats Plant recently completed and implemented the Rocky Flats Plant Community Relations Plan for public involvement in environmental restoration of the site. The plan was developed in cooperation with the plant's regulators, the U.S. Environmental Protection Agency and the Colorado Department of Health. In addition, citizens near the plant played a significant role in shaping the document through extensive community interviews and public comment. The result of these cooperative efforts is a plan that meets and exceeds the applicable federal and state community relations requirements for a cleanup program. In fact, the U.S. Environmental Protection Agency has used the Rocky Flats Plant Community Relations Plants a model for similar plans at other federal facilities. Plan development, however, is only the starting point for an effective community relations effort. The Rocky Flats Plant and the public will face many challenges together as we implement the plan and build a partnership for addressing environmental cleanup issues. (author)

  1. Progress towards a lightning ignition model for the Northern Rockies

    Science.gov (United States)

    Paul Sopko; Don Latham

    2010-01-01

    We are in the process of constructing a lightning ignition model specific to the Northern Rockies using fire occurrence, lightning strike, ecoregion, and historical weather, NFDRS (National Fire Danger Rating System), lightning efficiency and lightning "possibility" data. Daily grids for each of these categories were reconstructed for the 2003 fire season (...

  2. Biological impacts of oil pollution: rocky shores. V. 7

    International Nuclear Information System (INIS)

    1997-01-01

    Most people with access to the sea have at one time enjoyed looking into rockpools and searching for crabs under boulders. Rocky shores have a great deal of fascination for people and they are the closest that many of them will get to the mysteries below the low tide mark. They are found, in some form, on most of the world's coasts and their ecology has been the subject of many books, reports and scientific papers. Rocky shores encompass a variety of intertidal habitats and have a range of vulnerabilities to oil. While some areas are quickly and easily cleaned by natural forces others can trap oil in sensitive sub-habitats which may then be damaged and take many years to recover. Furthermore, rocky shores have an importance in the wider context of marine ecosystems and some provide important local fisheries resources, tourism and amenities. This report describes the factors that make some rocky shores more sensitive to oil spills than others and considers the most appropriate methods of clean-up. Case histories are used to illustrate the effects of spills and spill clean-up, as well as typical recovery rates. (UK)

  3. Rocky Mountain Research Station invasive species visionary white paper

    Science.gov (United States)

    D. E. Pearson; M. Kim; J. Butler

    2011-01-01

    Invasive species represent one of the single greatest threats to natural ecosystems and the services they provide. Effectively addressing the invasive species problem requires management that is based on sound research. We provide an overview of recent and ongoing invasive species research conducted by Rocky Mountain Research Station scientists in the Intermountain...

  4. Adsorption study for uranium in Rocky Flats groundwater

    International Nuclear Information System (INIS)

    Laul, J.C.; Rupert, M.C.; Harris, M.J.; Duran, A.

    1995-01-01

    Six adsorbents were studied to determine their effectiveness in removing uranium in Rocky Flats groundwater. The bench column and batch (Kd) tests showed that uranium can be removed (>99.9%) by four adsorbents. Bone Charcoal (R1O22); F-1 Alumina (granular activated alumina); BIOFIX (immobilized biological agent); SOPBPLUS (mixed metal oxide); Filtrasorb 300 (granular activated carbon); and Zeolite (clinoptilolite)

  5. Field guide to diseases & insects of the Rocky Mountain Region

    Science.gov (United States)

    Forest Health Protection. Rocky Mountain Region

    2010-01-01

    This field guide is a forest management tool for field identification of biotic and abiotic agents that damage native trees in Colorado, Kansas, Nebraska, South Dakota, and Wyoming, which constitute the USDA Forest Service's Rocky Mountain Region. The guide focuses only on tree diseases and forest insects that have significant economic, ecological, and/ or...

  6. Rocky Flats Plant Site Environmental Report for 1992

    Energy Technology Data Exchange (ETDEWEB)

    Cirrincione, D.A.; Erdmann, N.L. [eds.

    1992-12-31

    The Rocky Rats Plant Site Environmental Report provides summary information on the plant`s environmental monitoring programs and the results recorded during 1992. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population.

  7. Immune Thrombocytopenia as a Consequence of Rocky Mountain Spotted Fever.

    Science.gov (United States)

    Baldeo, Cherisse; Seegobin, Karan; Zuberi, Lara

    2017-01-01

    Primary immune thrombocytopenia (ITP) - also called idiopathic thrombocytopenic purpura or immune thrombocytopenic purpura - is an acquired thrombocytopenia caused by autoantibodies against platelet antigens. It is one of the more common causes of thrombocytopenia in otherwise asymptomatic adults. Rocky Mountain spotted fever (RMSF) is a potentially lethal, but curable, tick-borne disease. We present a case of ITP that was triggered by RMSF.

  8. Natural phenomena risk assessment at Rocky Flats Plant

    International Nuclear Information System (INIS)

    Foppe, T.L.

    1985-01-01

    A realistic approach is currently being used at the Rocky Flats Plant to assess the risks of natural phenomena events. The methodology addresses frequency of occurrence estimates, damage stress on the facility and vital equipment, material-at-risk, release fractions and source terms, leakpath, dispersion and dosimetric models, risk curves, and an uncertainty analysis. 28 references, 1 figure

  9. Aquatic Resources of Rocky Mountain Arsenal Adams County, Colorado

    Science.gov (United States)

    1989-09-01

    Consequently, temperatures rise and oxygen levels fall. Primary producers in these stretches shift from periphyton to phytoplankton (suspended algae ...trees and have rocky substrates. Primary production in these cold- water and coolwater reaches is generally limited to periphyton (attached algae ...Adams County. Biotic components investigated included phytoplankton , zooplankton, aquatic macrophytes, benthic macroinvertebrates, fish eggs and

  10. Erratum: Vascular epiphyte vegetation in rocky savannas of southeastern Brazil

    Czech Academy of Sciences Publication Activity Database

    Alves, R. J. V.; Kolbek, Jiří; Becker, J.

    2009-01-01

    Roč. 27, č. 4 (2009), s. 351-352 ISSN 0107-055X Institutional research plan: CEZ:AV0Z60050516 Keywords : epiphytes * Brazil * rocky savannas Subject RIV: EF - Botanics Impact factor: 0.868, year: 2009

  11. Rocky Planetary Debris Around Young WDs

    Science.gov (United States)

    Gaensicke, B.

    2014-04-01

    , the low C/Si ratio demonstrates that the planetary material is of rocky nature. * None of the 9 systems where we measure the C/O ratio shows evidence for carbon-dominated chemistry, implying that "carbon planets" are not common. * In the most polluted white dwarfs, we measure the debris abundances of up to 11 elements, enabling a detailed comparison between the chemistry of exo-planetary material with that of solar system meteorites. We find that the exo-planetary debris shares many characteristics of solar-system material, i.e. a wide spread in the relative abundances of Mg, Fe, Si, and O, a constant Al/Ca ratio, and evidence for differentiation in the form of Fe over-abundances All of the above is suggestive that thermal and collisional processing of planetary material in those systems might have been similar to that in the solar system.

  12. Canadian perspectives on food irradiation

    International Nuclear Information System (INIS)

    Kunstadt, P.

    1990-01-01

    Canada has been in the forefront of irradiation technology for over 30 years. Some 83 of the 147 irradiators used worldwide are Canadian-built, yet Canadian food processors have been very slow to use the technology. This paper is an update on the food irradiation regulatory situation in Canada and the factors that influence it. It also reviews some significant non-regulatory developments. (author)

  13. Sensitivity of very small glaciers in the Swiss Alps to future climate change

    Directory of Open Access Journals (Sweden)

    Matthias eHuss

    2016-04-01

    Full Text Available Very small glaciers (<0.5 km2 account for more than 80% of the total number of glaciers in mid- to low-latitude mountain ranges. Although their total area and volume is small compared to larger glaciers, they are a relevant component of the cryosphere, contributing to landscape formation, local hydrology and sea-level rise. Worldwide glacier monitoring mostly focuses on medium-sized to large glaciers leaving us with a limited understanding of the response of dwarf glaciers to climate change. In this study, we present a comprehensive modeling framework to assess past and future changes of very small glaciers at the mountain-range scale. Among other processes our model accounts for snow redistribution, changes in glacier geometry and the time-varying effect of supraglacial debris. It computes the mass balance distribution, the englacial temperature regime and proglacial runoff. The evolution of 1,133 individual glaciers in the Swiss Alps is modeled in detail until 2060 based on new distributed data sets. Our results indicate that 52% of all very small glaciers in Switzerland will completely disappear within the next 25 years. However, a few avalanche-fed glaciers at low elevation might be able to survive even substantial atmospheric warming. We find highly variable sensitivities of very small glaciers to air temperature change, with gently-sloping, low-elevation, and debris-covered glaciers being most sensitive.

  14. Study on comprehensive planning of rocky desertification in karst area of Chongqing

    Science.gov (United States)

    Zang, Yajun

    2017-11-01

    Chongqing is a key area for comprehensive treatment of rocky desertification in karst areas of china. Strengthening the comprehensive management of karst rocky desertification area, for the maintenance of ecological safety of Three Gorges Reservoir area, expanding the karst rocky desertification area people survival and development space, and improving the regional ecological conditions, have important practical significance to the construction of ecological civilization and building a harmonious society. Based on the investigation, analysis and arrangement of the data in the rocky desertification area, the paper puts forward the corresponding measures and phased targets for the treatment of the Rocky Desertification in the karst areas of Chongqing.

  15. Estimating the snow water equivalent on a glacierized high elevation site (Forni Glacier, Italy)

    Science.gov (United States)

    Senese, Antonella; Maugeri, Maurizio; Meraldi, Eraldo; Verza, Gian Pietro; Azzoni, Roberto Sergio; Compostella, Chiara; Diolaiuti, Guglielmina

    2018-04-01

    We present and compare 11 years of snow data (snow depth and snow water equivalent, SWE) measured by an automatic weather station (AWS) and corroborated by data from field campaigns on the Forni Glacier in Italy. The aim of the analysis is to estimate the SWE of new snowfall and the annual SWE peak based on the average density of the new snow at the site (corresponding to the snowfall during the standard observation period of 24 h) and automated snow depth measurements. The results indicate that the daily SR50 sonic ranger measurements and the available snow pit data can be used to estimate the mean new snow density value at the site, with an error of ±6 kg m-3. Once the new snow density is known, the sonic ranger makes it possible to derive SWE values with an RMSE of 45 mm water equivalent (if compared with snow pillow measurements), which turns out to be about 8 % of the total SWE yearly average. Therefore, the methodology we present is interesting for remote locations such as glaciers or high alpine regions, as it makes it possible to estimate the total SWE using a relatively inexpensive, low-power, low-maintenance, and reliable instrument such as the sonic ranger.

  16. Rapid response of alpine timberline vegetation to the Younger Dryas climate oscillation in the Colorado Rocky Mountains, USA

    International Nuclear Information System (INIS)

    Reasoner, M.A.; Jodry, M.A.

    2000-01-01

    Paleobotanical records from two high-altitude (>3,300 m) sites in Colorado show a clear and immediate response to the Younger Dryas climate oscillation. The Black Mountain Lake and Sky Pond records indicate that alpine timberline migrated upslope to near-modern elevations during the late Bolling-Allerod (13.6--12.9 ka). Subsequent declines in arboreal pollen percentages and accumulation rates during the Younger Dryas interval (12.9--11.7 ka) reflect a downslope displacement of the alpine timberline ecotone of 60--120 m in elevation. This change translates to a cooling of summer temperature by ∼0.4--0.9 C and is consistent with proposed Younger Dryas advances of alpine glaciers in the Rocky Mountains to positions close to Little Ice Age maxima. Alpine timberline readvanced upslope to elevations above both sites between 11.7 and 11.4 ka. The concomitant response of temperature-sensitive alpine timberline vegetation in Colorado and late-glacial changes in North Atlantic thermohaline circulating implicates a rapid, widespread atmospheric transmission of the Younger Dryas climate oscillation

  17. Rapid response of alpine timberline vegetation to the Younger Dryas climate oscillation in the Colorado Rocky Mountains, USA

    Energy Technology Data Exchange (ETDEWEB)

    Reasoner, M.A.; Jodry, M.A.

    2000-01-01

    Paleobotanical records from two high-altitude (>3,300 m) sites in Colorado show a clear and immediate response to the Younger Dryas climate oscillation. The Black Mountain Lake and Sky Pond records indicate that alpine timberline migrated upslope to near-modern elevations during the late Bolling-Allerod (13.6--12.9 ka). Subsequent declines in arboreal pollen percentages and accumulation rates during the Younger Dryas interval (12.9--11.7 ka) reflect a downslope displacement of the alpine timberline ecotone of 60--120 m in elevation. This change translates to a cooling of summer temperature by {approximately}0.4--0.9 C and is consistent with proposed Younger Dryas advances of alpine glaciers in the Rocky Mountains to positions close to Little Ice Age maxima. Alpine timberline readvanced upslope to elevations above both sites between 11.7 and 11.4 ka. The concomitant response of temperature-sensitive alpine timberline vegetation in Colorado and late-glacial changes in North Atlantic thermohaline circulating implicates a rapid, widespread atmospheric transmission of the Younger Dryas climate oscillation.

  18. The challenge and future of rocky desertification control in karst areas in southwest China

    Science.gov (United States)

    Zhang, J. Y.; Dai, M. H.; Wang, L. C.; Zeng, C. F.; Su, W. C.

    2016-01-01

    Karst rocky desertification occurs after vegetation deteriorates as a result of intensive land use, which leads to severe water loss and soil erosion and exposes basement rocks, creating a rocky landscape. Karst rocky desertification is found in humid areas in southwest China, the region most seriously affected by rocky desertification in the world. In order to promote ecological restoration and help peasants out of poverty, the Chinese government carried out the first phase of a rocky desertification control project from 2006 to 2015, which initially contained the expansion of rocky desertification. Currently, the Chinese government is prepared to implement the second phase of the rocky desertification control project, and therefore it is essential to summarise the lessons learned over the last 10 years of the first phase. In this paper, we analyse the driving social and economic factors behind rocky desertification, summarise the scientific research on rocky desertification in the region, and finally identify the main problems facing rocky desertification control. In addition, we put forward several policy suggestions that take into account the perspective of local peasants, scientific research, and China's economic development and urbanisation process. These suggestions include promoting the non-agriculturalization of household livelihoods, improving ecological compensation, strengthening the evaluation of rocky desertification control and dynamic monitoring, and strengthening research on key ecological function recovery technologies and supporting technologies.

  19. Latest Pleistocene and Holocene Glacier Fluctuations in southernmost Patagonia

    Science.gov (United States)

    Menounos, B.; Maurer, M.; Clague, J. J.; osborn, G.; Ponce, F.; Davis, P. T.; Rabassa, J.; Coronato, A.; Marr, R.

    2011-12-01

    Summer insolation has been proposed to explain long-term glacier fluctuations during the Holocene. If correct, the record of glacier fluctuations at high latitudes in the Southern Hemisphere should differ from that in the Northern Hemisphere. Testing this insolation hypothesis has been hampered by dating uncertainties of many Holocene glacier chronologies from Patagonia. We report on our ongoing research aimed at developing a regional glacier chronology at the southern end of the Andes north and west of Ushuaia, Argentina. We have found evidence for an advance of cirque glaciers at the end of the Pleistocene; one or locally two closely spaced moraines extend up to 2 km beyond Little Ice Age moraines. Radiocarbon dating of terrestrial macrofossils recovered from basal sediments behind two of these moraines yielded ages of 10,320 ± 25 and 10,330 ± 30 14C yr BP. These moraines may record glacier advances coeval with the Antarctic Cold Reversal; surface exposure dating of these moraines is currently in progress to test this hypothesis. We find no evidence of Holocene moraines older than 6800 14C yr BP, based on the distribution of Hudson tephra of that age. At some sites, there is evidence for an early Neoglacial advance of glaciers slightly beyond (Peru. We have documented multiple wood mats with stumps in growth position separated by till units in a 100 m section of the northeast lateral moraine at Stoppani Glacier (54.78 S, 68.98 W), 50 km west of Ushuaia. Ten radiocarbon ages on these wood mats range in age from 3510 ± 15 to 135 ± 15 14C yr BP. The mats decrease in age up-section; many overlap with published age ranges for Neoglacial advances in western Canada. Taken together, these data: a) do not support the summer insolation hypothesis for Holocene glacier fluctuations in southernmost Patagonia; b) confirm paleobotanical evidence for a warm, dry early Holocene; and c) suggest that many Neoglacial advances in southernmost Patagonia and western North America

  20. Elevation Changes of Ice Caps in the Canadian Arctic Archipelago

    Science.gov (United States)

    Abdalati, W.; Krabill, W.; Frederick, E.; Manizade, S.; Martin, C.; Sonntag, J.; Swift, R.; Thomas, R.; Yungel, J.; Koerner, R.

    2004-01-01

    Precise repeat airborne laser surveys were conducted over the major ice caps in the Canadian Arctic Archipelago in the spring of 1995 and 2000 in order to measure elevation changes in the region. Our measurements reveal thinning at lower elevations (below 1600 m) on most of the ice caps and glaciers, but either very little change or thickening at higher elevations in the ice cap accumulation zones. Recent increases in precipitation in the area can account for the slight thickening where it was observed, but not for the thinning at lower elevations. For the northern ice caps on the Queen Elizabeth Islands, thinning was generally less than 0.5 m/yr , which is consistent with what would be expected from the warm temperature anomalies in the region for the 5-year period between surveys and appears to be a continuation of a trend that began in the mid 1980s. Further south, however, on the Barnes and Penny ice caps on Baffin Island, this thinning was much more pronounced at over 1 m/yr in the lower elevations. Here temperature anomalies were very small, and the thinning at low elevations far exceeds any associated enhanced ablation. The observations on Barnes, and perhaps Penny are consistent with the idea that the observed thinning is part of a much longer term deglaciation, as has been previously suggested for Barnes Ice Cap. Based on the regional relationships between elevation and elevation-change in our data, the 1995-2000 mass balance for the region is estimated to be 25 cu km/yr of ice, which corresponds to a sea level increase of 0.064 mm/ yr . This places it among the more significant sources of eustatic sea level rise, though not as substantial as Greenland ice sheet, Alaskan glaciers, or the Patagonian ice fields.

  1. Canadian leadership in energy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-15

    Canada's energy is complex and an important resource as it fuels and funds the economy. The unique character of Canada's energy production and consumption provides strength to the country. The purpose of this booklet was to highlight Canada's energy production and consumption and to demonstrate Canada's rank globally with other major global energy players. The document also presented information on the value of Canada's energy exports, Canada's relationship with the United States, and Canada's energy-related carbon dioxide emissions. Specifically, the document discussed Canada's energy in a global context; the value of Canada's energy exports; domestic value of energy; Canada's unique energy mix; Canada's electricity mix; Canada's carbon dioxide emissions; energy strategies; and the importance of energy to Canadians. It was concluded that there are 14 federal, provincial and territorial jurisdictions managing their respective energy resources. All of these regions, with the exception of Saskatchewan have produced an energy strategy document or a climate change action plan focusing on 8 areas of action, notably awareness; benefit; efficiency; development; diversification; electricity; and emissions. refs., tabs., figs.

  2. Canadian programme overview

    International Nuclear Information System (INIS)

    Fluke, R.J.

    1997-01-01

    In a severe accident, hydrogen is released into containment. When it is well mixed, the hydrogen mixture is nonflammable because there is sufficient dilution by the large containment volume. This is the desired end point. However, the release may occur into smaller compartments of containment, stratification may occur, and local pockets of flammable mixtures may arise if hydrogen is released faster than processes that mix and disperse it. Long term hydrogen generation from water radiolysis must also be considered. Hydrogen mitigation and control strategies adopted or considered in Canada include fanforced mixing, glow plug igniters, recombiners, venting through filters, or combinations of these. The Canadian hydrogen programme is focussed on understanding hydrogen combustion behaviour and providing the data needed to demonstrate the adequacy of hydrogen mitigation and control strategies. The programme includes both experimental and modelling components of hydrogen combustion and distribution. Experiments include mixing tests, deflagration tests, diffusion flames, transition from deflagration to detonation, and testing the performance of igniters and recombiners. Modelling is focussing on the GOTHIC code as an industry standard. Detailed three dimensional modelling of gas mixing and combustion are underway, and a code validation matrix is being assembled for validation exercises. Significant progress has been made, highlights from which are being presented at this workshop. (author)

  3. Canadian fuel development program

    International Nuclear Information System (INIS)

    Gacesa, M.; Young, E.G.

    1992-11-01

    CANDU power reactor fuel has demonstrated an enviable operational record. More than 99.9% of the bundles irradiated have provided defect-free service. Defect excursions are responsible for the majority of reported defects. In some cases research and development effort is necessary to resolve these problems. In addition, development initiatives are also directed at improvements of the current design or reduction of fueling cost. The majority of the funding for this effort has been provided by COG (CANDU Owners' Group) over the past 10 to 15 years. This paper contains an overview of some key fuel technology programs within COG. The CANDU reactor is unique among the world's power reactors in its flexibility and its ability to use a number of different fuel cycles. An active program of analysis and development, to demonstrate the viability of different fuel cycles in CANDU, has been funded by AECL in parallel with the work on the natural uranium cycle. Market forces and advances in technology have obliged us to reassess and refocus some parts of our effort in this area, and significant success has been achieved in integrating all the Canadian efforts in this area. This paper contains a brief summary of some key components of the advanced fuel cycle program. (Author) 4 figs., tab., 18 refs

  4. Canadian leadership in energy

    International Nuclear Information System (INIS)

    2010-09-01

    Canada's energy is complex and an important resource as it fuels and funds the economy. The unique character of Canada's energy production and consumption provides strength to the country. The purpose of this booklet was to highlight Canada's energy production and consumption and to demonstrate Canada's rank globally with other major global energy players. The document also presented information on the value of Canada's energy exports, Canada's relationship with the United States, and Canada's energy-related carbon dioxide emissions. Specifically, the document discussed Canada's energy in a global context; the value of Canada's energy exports; domestic value of energy; Canada's unique energy mix; Canada's electricity mix; Canada's carbon dioxide emissions; energy strategies; and the importance of energy to Canadians. It was concluded that there are 14 federal, provincial and territorial jurisdictions managing their respective energy resources. All of these regions, with the exception of Saskatchewan have produced an energy strategy document or a climate change action plan focusing on 8 areas of action, notably awareness; benefit; efficiency; development; diversification; electricity; and emissions. refs., tabs., figs.

  5. Changing Hydrology in Glacier-fed High Altitude Andean Peatbogs

    Science.gov (United States)

    Slayback, D. A.; Yager, K.; Baraer, M.; Mohr, K. I.; Argollo, J.; Wigmore, O.; Meneses, R. I.; Mark, B. G.

    2012-12-01

    Montane peatbogs in the glacierized Andean highlands of Peru and Bolivia provide critical forage for camelids (llama and alpaca) in regionally extensive pastoral agriculture systems. During the long dry season, these wetlands often provide the only available green forage. A key question for the future of these peatbog systems, and the livelihoods they support, is the impact of climate change and glacier recession on their hydrology, and thus forage production. We have already documented substantial regional glacier recession, of, on average, approximately 30% of surface area over the past two decades. As glaciers begin to retreat under climate change, there is initially a period of increased meltwater outflow, culminating in a period of "peak water", and followed by a continual decline in outflows. Based on previous work, we know that some glaciers in the region have already passed peak water conditions, and are now declining. To better understand the impacts of these processes on peatbog hydrology and productivity, we have begun collecting a variety of surface data at several study sites in both Bolivia and Peru. These include precipitation, stream flow, water levels, water chemistry and isotope analyses, and peatbog biodiversity and biomass. These measurements will be used in conjunction with a regional model driven by satellite data to predict likely future impacts. We will present the results from these initial surface measurements, and an overview of satellite datasets to be used in the regional model.

  6. Technical note: Representing glacier geometry changes in a semi-distributed hydrological model

    Directory of Open Access Journals (Sweden)

    J. Seibert

    2018-04-01

    Full Text Available Glaciers play an important role in high-mountain hydrology. While changing glacier areas are considered of highest importance for the understanding of future changes in runoff, glaciers are often only poorly represented in hydrological models. Most importantly, the direct coupling between the simulated glacier mass balances and changing glacier areas needs feasible solutions. The use of a complex glacier model is often not possible due to data and computational limitations. The Δh parameterization is a simple approach to consider the spatial variation of glacier thickness and area changes. Here, we describe a conceptual implementation of the Δh parameterization in the semi-distributed hydrological model HBV-light, which also allows for the representation of glacier advance phases and for comparison between the different versions of the implementation. The coupled glacio-hydrological simulation approach, which could also be implemented in many other semi-distributed hydrological models, is illustrated based on an example application.

  7. Health practices of Canadian physicians.

    Science.gov (United States)

    Frank, Erica; Segura, Carolina

    2009-08-01

    To study the health and health practices of Canadian physicians, which can often influence patient health. Mailed survey. Canada. A random sample of 8100 Canadian physicians; 7934 were found to be eligible and 3213 responded (40.5% response rate). Factors that influence health, such as consumption of fruits and vegetables, amount of exercise and alcohol consumption, smoking status, body mass idex, and participation in preventive health screening measures, as well as work-life balance and emotional stability. Canadian physicians are healthy. More than 90% reported being in good to excellent health, and only 5% reported that poor physical or mental health made it difficult to handle their workload more than half the time in the previous month (although a quarter had reduced work activity because of long-term health conditions). Eight percent were obese, 3% currently smoked cigarettes, and 1% typically consumed 5 drinks or more on days when they drank alcohol. Physicians averaged 4.7 hours of exercise per week and ate fruits and vegetables 4.8 times a day. Their personal screening practices were largely compliant with Canadian Task Force on Preventive Health Care recommendations. They averaged 38 hours per week on patient care and 11 hours on other professional activities. Fifty-seven percent agreed that they had a good work-life balance, and 11% disagreed with the statement "If I can, I work when I am ill." Compared with self-reports from the general Canadian population, Canadian physicians, like American physicians, seem to be healthy and to have generally healthy behaviour. There is, however, room for improvement in physicians' personal and professional well-being, and improving their personal health practices could be an efficient and beneficent way to improve the health of all Canadians.

  8. Numerical Modeling of Large-Scale Rocky Coastline Evolution

    Science.gov (United States)

    Limber, P.; Murray, A. B.; Littlewood, R.; Valvo, L.

    2008-12-01

    Seventy-five percent of the world's ocean coastline is rocky. On large scales (i.e. greater than a kilometer), many intertwined processes drive rocky coastline evolution, including coastal erosion and sediment transport, tectonics, antecedent topography, and variations in sea cliff lithology. In areas such as California, an additional aspect of rocky coastline evolution involves submarine canyons that cut across the continental shelf and extend into the nearshore zone. These types of canyons intercept alongshore sediment transport and flush sand to abyssal depths during periodic turbidity currents, thereby delineating coastal sediment transport pathways and affecting shoreline evolution over large spatial and time scales. How tectonic, sediment transport, and canyon processes interact with inherited topographic and lithologic settings to shape rocky coastlines remains an unanswered, and largely unexplored, question. We will present numerical model results of rocky coastline evolution that starts with an immature fractal coastline. The initial shape is modified by headland erosion, wave-driven alongshore sediment transport, and submarine canyon placement. Our previous model results have shown that, as expected, an initial sediment-free irregularly shaped rocky coastline with homogeneous lithology will undergo smoothing in response to wave attack; headlands erode and mobile sediment is swept into bays, forming isolated pocket beaches. As this diffusive process continues, pocket beaches coalesce, and a continuous sediment transport pathway results. However, when a randomly placed submarine canyon is introduced to the system as a sediment sink, the end results are wholly different: sediment cover is reduced, which in turn increases weathering and erosion rates and causes the entire shoreline to move landward more rapidly. The canyon's alongshore position also affects coastline morphology. When placed offshore of a headland, the submarine canyon captures local sediment

  9. Rockfalls and glacier contraction: Cirque de Troumouse

    Directory of Open Access Journals (Sweden)

    Gellatly, Anne F.

    1994-12-01

    Full Text Available The incidence of rockfalls within the Cirque de Troumouse appears to have been triggered by ice wastage and the resultant geomorphological pattern of rockfall deposits affords an insight into the migration of headwall weathering zones. Observations of the rockfall deposits indicate clear geological controls which maybe directly related to the exposure of the headwall zone during phases of glacier wastage

    [es] Las caldas de piedras en el Circo de Troumouse parecen haber sido desencadenadas por la acción del hielo, y el modelo geomorfológico de depósitos de bloques resultante proporciona una idea sobre la migración de las zonas de meteorización en las paredes. Las observaciones de tales depósitos indican la existencia de claros controles geológicos que pueden relacionarse directamente con la exposición de la pared durante las fases de fusión glaciar.
    [fr] Les chutes des pierres dans le cirque de Troumouse paraissent avoir été déclenchées par l'action de la glace, et le modèle géomorphologique des dépôts de blocs résultant donne une idée de la migration des zones de météorisation dans les parois. Les observations de ces dépôts indiquent l'existence de contrôles géologiques très clairs qui peuvent être directement liés à l'exposition de la paroi durant les phases de fusion glaciaire.

  10. Impacts of glacier recession and declining meltwater on mountain societies

    DEFF Research Database (Denmark)

    Carey, Mark; Molden, Olivia C.; Rasmussen, Mattias Borg

    2017-01-01

    . It identifies four main areas of existing research: (1) socioeconomic impacts; (2) hydropower; (3) agriculture, irrigation, and food security; and (4) cultural impacts. The article also suggests paths forward for social sciences, humanities, and natural sciences research that could more accurately detect......, including irrigation, agriculture, hydropower, potable water, livelihoods, recreation, spirituality, and demography. Unfortunately, research focusing on the human impacts of glacier runoff variability in mountain regions remains limited, and studies often rely on assumptions rather than concrete evidence...... about the effects of shrinking glaciers on mountain hydrology and societies. This article provides a systematic review of international research on human impacts of glacier meltwater variability in mountain ranges worldwide, including the Andes, Alps, greater Himalayan region, Cascades, and Alaska...

  11. Natural and artificial radioactivity in the Svalbard glaciers

    International Nuclear Information System (INIS)

    Pinglot, J.F.; Pourchet, M.

    1994-01-01

    Natural and artificial radioactivity in the snow of 10 Svalbard glaciers has been measured from 31 ice core samples, drilled between 1981 and 1993. Of these ice cores, seven exhibit the well-known level arising from the fallout of the 1961-62 atmospheric thermonuclear tests. The second level, due to the Chernobyl accident (26 April 1986), has been detected in all the studied glaciers; the maximum 137 Cs fallout reaches 22 Bq kg -1 and shows a high variability. The natural radioactivity, mostly due to 210 Pb, shows an in-depth variation which is not governed by its half-life (22.2 years). These measurements serve many glaciological purposes: absolute dating of the snow layers; air-snow transfer and fallout studies; the determination of mean annual mass balances in the accumulation area of glaciers and their associated spatio-temporal variations. (author)

  12. Supraglacial Ponds Regulate Runoff From Himalayan Debris-Covered Glaciers

    Science.gov (United States)

    Irvine-Fynn, Tristram D. L.; Porter, Philip R.; Rowan, Ann V.; Quincey, Duncan J.; Gibson, Morgan J.; Bridge, Jonathan W.; Watson, C. Scott; Hubbard, Alun; Glasser, Neil F.

    2017-12-01

    Meltwater and runoff from glaciers in High Mountain Asia is a vital freshwater resource for one-fifth of the Earth's population. Between 13% and 36% of the region's glacierized areas exhibit surface debris cover and associated supraglacial ponds whose hydrological buffering roles remain unconstrained. We present a high-resolution meltwater hydrograph from the extensively debris-covered Khumbu Glacier, Nepal, spanning a 7 month period in 2014. Supraglacial ponds and accompanying debris cover modulate proglacial discharge by acting as transient and evolving reservoirs. Diurnally, the supraglacial pond system may store >23% of observed mean daily discharge, with mean recession constants ranging from 31 to 108 h. Given projections of increased debris cover and supraglacial pond extent across High Mountain Asia, we conclude that runoff regimes may become progressively buffered by the presence of supraglacial reservoirs. Incorporation of these processes is critical to improve predictions of the region's freshwater resource availability and cascading environmental effects downstream.

  13. Ecological responses to experimental glacier-runoff reduction in alpine rivers

    DEFF Research Database (Denmark)

    Cauvy-Fraunié, Sophie; Andino, Patricio; Espinosa, Rodrigo

    2016-01-01

    Glacier retreat is a worldwide phenomenon with important consequences for the hydrological cycle and downstream ecosystem structure and functioning. To determine the effects of glacier retreat on aquatic communities, we conducted a 4-year flow manipulation in a tropical glacier-fed stream. Compared...

  14. Mapping tide-water glacier dynamics in east Greenland using landsat data

    Science.gov (United States)

    Dwyer, John L.

    1995-01-01

    Landsat multispectral scanner and thematic mapper images were co-registered For the Kangerdlugssuaq Fjord region in East Greenland and were used to map glacier drainage-basin areas, changes in the positions of tide-water glacier termini and to estimate surface velocities of the larger tide-water glaciers. Statistics were compiled to document distance and area changes to glacier termini. The methodologies developed in this study are broadly applicable to the investigation of tide-water glaciers in other areas. The number of images available for consecutive years and the accuracy with which images are co-registered are key factors that influence the degree to which regional glacier dynamics can be characterized using remotely sensed data.Three domains of glacier state were interpreted: net increase in terminus area in the southern part of the study area, net loss of terminus area for glaciers in upper Kangerdlugssuaq Fjord and a slight loss of glacier terminus area northward from Ryberg Fjord. Local increases in the concentrations of drifting icebergs in the fjords coincide with the observed extension of glacier termini positions Ice-surface velocity estimates were derived for several glaciers using automated image cross-correlation techniques The velocity determined for Kangerdlugssuaq Gletscher is approximately 5.0 km a−1 and that for Kong Christian IV Gletscher is 0.9 km a−1. The continuous presence of icebergs and brash ice in front of these glaciers indicates sustained rates of ice-front calving.

  15. Midlatitude Forcing Mechanisms for Glacier Mass Balance Investigated Using General Circulation Models

    NARCIS (Netherlands)

    Reichert, B.K.; Bengtsson, L.; Oerlemans, J.

    2001-01-01

    A process-oriented modeling approach is applied in order to simulate glacier mass balance for individual glaciers using statistically downscaled general circulation models (GCMs). Glacier-specific seasonal sensitivity characteristics based on a mass balance model of intermediate complexity are used

  16. Observed thinning of Totten Glacier is linked to coastal polynya variability

    NARCIS (Netherlands)

    Khazendar, A.; Schodlok, M.P.; Fenty, I.; Ligtenberg, S.R.M.; Rignot, Eric; van den Broeke, M.R.

    2013-01-01

    Analysis of ICESat-1 data (2003–2008) shows significant surface lowering of Totten Glacier, the glacier discharging the largest volume of ice in East Antarctica, and less change on nearby Moscow University Glacier. After accounting for firn compaction anomalies, the thinning appears to coincide with

  17. Pond dynamics and supraglacial-englacial connectivity on debris-covered Lirung Glacier

    NARCIS (Netherlands)

    Miles, Evan Stewart; Steiner, Jakob|info:eu-repo/dai/nl/119338653; Willis, Ian C.; Buri, Pascal; Immerzeel, Walter Willem|info:eu-repo/dai/nl/290472113; Chesnokova, Anna; Pellicciotti, Francesca

    The hydrological systems of heavily-downwasted debris-covered glaciers differ from clean-ice glaciers due to the hummocky surface and debris mantle of such glaciers, leading to a relatively limited understanding of drainage pathways. Supraglacial ponds represent sinks within the discontinuous

  18. Rising river flows throughout the twenty-first century in two Himalayan glacierized watersheds

    NARCIS (Netherlands)

    Immerzeel, W.W.|info:eu-repo/dai/nl/290472113; Pelliciotti, F.; Bierkens, M.F.P.|info:eu-repo/dai/nl/125022794

    2013-01-01

    Greater Himalayan glaciers are retreating and losing mass at rates comparable to glaciers in other regions of the world1–5 . Assessments of future changes and their associated hydrological impacts are scarce, oversimplify glacier dynamics or include a limited number of climate models6–9 . Here, we

  19. Holocene glacier variability: three case studies using an intermediate-complexity climate model

    NARCIS (Netherlands)

    Weber, S.L.; Oerlemans, J.

    2003-01-01

    Synthetic glacier length records are generated for the Holocene epoch using a process-based glacier model coupled to the intermediate-complexity climate model ECBilt. The glacier model consists of a massbalance component and an ice-flow component. The climate model is forced by the insolation change

  20. What influences climate and glacier change in southwestern China?

    Science.gov (United States)

    Yasunari, Teppei J.

    2011-12-01

    The subject of climate change in the Tibetan Plateau (TP) and Himalayas has taken on increasing importance because of the availability of water resources from their mountain glaciers (Immerzeel et al 2010). Many of the glaciers over these regions have been retreating, while some are advancing and stable (Yao et al 2004, Scherler et al 2011). Other studies report that some glaciers in the Himalayas show acceleration of their shrinkage (e.g., Fujita and Nuimura 2011). However, the causes of glacier melting are still difficult to grasp because of the complexity of climatic change and its influence on glacier issues. Despite this, it is vital that we pursue further study to enable future predictions of glacier changes. The paper entitled 'Climate and glacier change in southwestern China during the past several decades' by Li et al (2011) provided carefully analyzed, quality controlled, long-term data on atmospheric temperature and precipitation during the period 1961-2008. The data were obtained from 111 Chinese stations. The researchers performed systematic analyses of temperature and precipitation over the whole southwestern Chinese domain. They discussed those changes in terms of other meteorological components such as atmospheric circulation patterns, radiation and altitude difference, and then showed how these factors could contribute to climate and glacier changes in the region. Air temperature and precipitation are strongly associated with glacier mass balance because of heat balance and the addition of mass when it snows. Temperature warming trends over many places in southwestern China were unequivocally dominant in all seasons and at higher altitudes. This indicates that the heat contribution to the glaciers has been increasing. On the other hand, precipitation has a wider variability in time and space. It is more difficult to clearly understand the effect of precipitation on the climate and glacier melting characteristics in the whole of southwestern China

  1. Estimating Velocities of Glaciers Using Sentinel-1 SAR Imagery

    Science.gov (United States)

    Gens, R.; Arnoult, K., Jr.; Friedl, P.; Vijay, S.; Braun, M.; Meyer, F. J.; Gracheva, V.; Hogenson, K.

    2017-12-01

    In an international collaborative effort, software has been developed to estimate the velocities of glaciers by using Sentinel-1 Synthetic Aperture Radar (SAR) imagery. The technique, initially designed by the University of Erlangen-Nuremberg (FAU), has been previously used to quantify spatial and temporal variabilities in the velocities of surging glaciers in the Pakistan Karakoram. The software estimates surface velocities by first co-registering image pairs to sub-pixel precision and then by estimating local offsets based on cross-correlation. The Alaska Satellite Facility (ASF) at the University of Alaska Fairbanks (UAF) has modified the software to make it more robust and also capable of migration into the Amazon Cloud. Additionally, ASF has implemented a prototype that offers the glacier tracking processing flow as a subscription service as part of its Hybrid Pluggable Processing Pipeline (HyP3). Since the software is co-located with ASF's cloud-based Sentinel-1 archive, processing of large data volumes is now more efficient and cost effective. Velocity maps are estimated for Single Look Complex (SLC) SAR image pairs and a digital elevation model (DEM) of the local topography. A time series of these velocity maps then allows the long-term monitoring of these glaciers. Due to the all-weather capabilities and the dense coverage of Sentinel-1 data, the results are complementary to optically generated ones. Together with the products from the Global Land Ice Velocity Extraction project (GoLIVE) derived from Landsat 8 data, glacier speeds can be monitored more comprehensively. Examples from Sentinel-1 SAR-derived results are presented along with optical results for the same glaciers.

  2. Glacier seismology: eavesdropping on the ice-bed interface

    Science.gov (United States)

    Walter, F.; Röösli, C.

    2015-12-01

    Glacier sliding plays a central role in ice dynamics. A number of remote sensing and deep drilling initiatives have therefore focused on the ice-bed interface. Although these techniques have provided valuable insights into bed properties, they do not supply theorists with data of sufficient temporal and spatial resolution to rigorously test mathematical sliding laws. As an alternative, passive seismic techniques have gained popularity in glacier monitoring. Analysis of glacier-related seismic sources ('icequakes') has become a useful technique to study inaccessible regions of the cryosphere, including the ice-bed interface. Seismic monitoring networks on the polar ice sheets have shown that ice sliding is not only a smooth process involving viscous deformation and regelation of basal ice layers. Instead, ice streams exhibit sudden slip episodes over their beds and intermittent phases of partial or complete stagnation. Here we discuss new and recently published discoveries of basal seismic sources beneath various glacial bodies. We revisit basal seismicity of hard-bedded Alpine glaciers, which is not the result of pure stick-slip motion. Sudden changes in seismicity suggest that the local configuration of the subglacial drainage system undergoes changes on sub daily time scales. Accordingly, such observations place constraints on basal resistance and sliding of hard-bedded glaciers. In contrast, certain clusters of stick-slip dislocations associated with micro seismicity beneath the Greenland ice sheet undergo diurnal variations in magnitudes and inter event times. This is best explained with a soft till bed, which hosts the shear dislocations and whose strength varies in response to changes in subglacial water pressure. These results suggest that analysis of basal icequakes is well suited for characterizing glacier and ice sheet beds. Future studies should address the relative importance between "smooth" and seismogenic sliding in different glacial environments.

  3. Canadian perspectives in evaluating transparency

    International Nuclear Information System (INIS)

    Herwig, L.

    2007-01-01

    The Canadian Nuclear Safety Commission's mission is to regulate the use of nuclear energy and materials to protect the health, safety, and security of Canadians and the environment, as well as to respect Canada's international commitments on the peaceful use of nuclear energy. In 2001, the CNSC established a vision to be one of the best nuclear regulators in the world and established four strategic priorities of effectiveness, transparency, excellence in staff, and efficiency. While fulfilling a very comprehensive mandate, the CNSC operates with a. very clear vision of its clientele - the Canadian people. That commitment guides every employee and every action of the CNSC and ensures a firm commitment to transparency. The presentation will begin with a brief overview of the worldwide context of transparency and transparency measurement, with a look at what lessons can be learned from other organizations and initiatives. It will look broadly at the Canadian context and the government framework that establishes transparency, including the keystone legislation of the Access to Information Act. The presentation will then focus on the Canadian Nuclear Safety Commission. The CNSC is firmly committed to putting additional measures in place to ensure transparency, which is being done concurrently with an overall organisational performance measurement system. It is within this framework that the presentation will address the transparency efforts at the CNSC as well transparency measurement activities. And, finally, the presentation will look at future directions for transparency and its measurement at the CNSC. (author)

  4. Snow chemistry of high altitude glaciers in the French Alps

    OpenAIRE

    MAUPETIT, FRANÇOIS; DELMAS, ROBERT J.

    2011-01-01

    Snow samples were collected as snowcores in the accumulation zone of four high altitude glaciers (2980–3540 m.a.s.l.) from each of the 4 highest mountain areas of the French Alps, during 3 consecutive years: 1989, 1990 and 1991. Sampling was performed in spring (∼ May), before the onset of late spring–summer percolation. The accumulated snow therefore reflects winter and spring conditions. A complementary sampling of fresh-snow was performed on an event basis, on one of the studied glaciers, ...

  5. Southern Alaska Glaciers: Spatial and Temporal Variations in Ice Volume

    Science.gov (United States)

    Sauber, J.; Molnia, B. F.; Lutchke, S.; Rowlands, D.; Harding, D.; Carabajal, C.; Hurtado, J. M.; Spade, G.

    2004-01-01

    Although temperate mountain glaciers comprise less than 1% of the glacier-covered area on Earth, they are important because they appear to be melting rapidly under present climatic conditions and, therefore, make significant contributions to rising sea level. In this study, we use ICESat observations made in the last 1.5 years of southern Alaska glaciers to estimate ice elevation profiles, ice surface slopes and roughness, and bi-annual and/or annual ice elevation changes. We report initial results from the near coastal region between Yakutat Bay and Cape Suckling that includes the Malaspina and Bering Glaciers. We show and interpret ice elevations changes across the lower reaches of the Bagley Ice Valley for the period between October 2003 and May 2004. In addition, we use off-nadir pointing observations to reference tracks over the Bering and Malaspina Glaciers in order to estimate annual ice elevation change. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Shuttle Radar Topography Mission (SRTM) derived DEMs are used to estimate across track regional slopes between ICESat data acquisitions. Although the distribution and quantity of ICESat elevation profiles with multiple, exact repeat data is currently limited in Alaska, individual ICESat data tracks, provide an accurate reference surface for comparison to other elevation data (e.g. ASTER and SRTM X- and C-band derived DEMs). Specifically we report the elevation change over the Malaspina Glacier's piedmont lobe between a DEM derived from SRTM C-band data acquired in Feb. 2000 and ICESat Laser #2b data from Feb.-March 2004. We also report use of ICESat elevation data to enhance ASTER derived absolute DEMs. Mountain glaciers generally have rougher surfaces and steeper regional slopes than the ice sheets for which the ICESat design was optimized. Therefore, rather than averaging ICESat observations over large regions or relying on crossovers, we are working with well-located ICESat

  6. Revisited Inventory of Glaciers on Axel Heiberg Island, Nunavut

    Science.gov (United States)

    Thomson, L.; Osinski, G.

    2009-05-01

    As documented in the IPCC's Climate Change 2007 report, the high latitude regions of the Northern Hemisphere are experiencing the highest rates of warming. Given that 35% of the global glacial ice exists within the Arctic Archipelago, this region provides an excellent laboratory for monitoring the anticipated degree of glacial recession [1]. Evidence of arctic warming through negative mass balance trends has been detected in several studies already [e.g., 2]. Here, we show the importance and value of historical records in the task of monitoring glacial retreat. A highly detailed inventory developed by S. Ommanney in 1969 [3], has been revisited and transformed into digital format for the purposes of integration with modern inventories. The Ommanney inventory covers the entirety of Axel Heiberg Island , NU, and includes details often lacking in present day inventories, including orientations (accumulation and ablation zones), elevations (highest, lowest, elevation of the snowline, and the mean elevations of both the accumulation and ablation areas), length (of the ablation area, exposed ice, and of the total glacier including debris cover), area (of the ablation area, exposed ice, and of the total glacier), accumulation area ratio (AAR), depth, volume, and a six digit code which gives qualitative details on glacier attributes. This report is one of the most thorough and comprehensive glacier inventory report ever published in Canada. More recent inventories used for comparison include the glacier extents created by the National Topographic System based on photography from 1980-1987, as well as extents developed by Dr. Luke Copland for the Global Land Ice Measurements from Space (GLIMS) database using 1999-2000 satellite imagery. Our preliminary results show that approximately 90% of ice bodies under 0.2km on Axel Heiberg Island have disappeared entirely in the 40 year period of interest. The issue of glacier definition will be discussed as a possible cause of these

  7. Pathways of warm water to the Northeast Greenland outlet glaciers

    Science.gov (United States)

    Schaffer, Janin; Timmermann, Ralph; Kanzow, Torsten; Arndt, Jan Erik; Mayer, Christoph; Schauer, Ursula

    2015-04-01

    The ocean plays an important role in modulating the mass balance of the Greenland Ice Sheet by delivering heat to the marine-terminating outlet glaciers surrounding the Greenland coast. The warming and accumulation of Atlantic Water in the subpolar North Atlantic has been suggested to be a potential driver of the glaciers' retreat over the last decades. The shelf regions thus play a critical role for the transport of Atlantic Water towards the glaciers, but also for the transfer of freshwater towards the deep ocean. A key region for the mass balance of the Greenland Ice Sheet is the Northeast Greenland Ice Stream. This large ice stream drains the second-largest basin of the Greenland Ice Sheet and feeds three outlet glaciers. The largest one is Nioghalvfjerdsfjorden (79°N-Glacier) featuring an 80 km long floating ice tongue. Both the ocean circulation on the continental shelf off Northeast Greenland and the circulation in the cavity below the ice tongue are weakly constrained so far. In order to study the relevant processes of glacier-ocean interaction we combine observations and model work. Here we focus on historic and recent hydrographic observations and on the complex bathymetry in the Northeast Greenland shelf region, which is thought to steer the flux of warm Atlantic water onto the continental shelf and into the sub-ice cavity beneath the 79°N-Glacier. We present a new global topography data set, RTopo-2, which includes the most recent surveys on the Northeast Greenland continental shelf and provides a detailed bathymetry for all around Greenland. In addition, RTopo-2 contains ice and bedrock surface topographies for Greenland and Antarctica. Based on the updated ocean bathymetry and a variety of hydrographic observations we show the water mass distribution on the continental shelf off Northeast Greenland. These maps enable us to discuss possible supply pathways of warm modified Atlantic waters on the continental shelf and thus potential ways of heat

  8. Dynamic interactions between glacier and glacial lake in the Bhutan Himalaya

    Science.gov (United States)

    Tsutaki, S.; Fujita, K.; Yamaguchi, S.; Sakai, A.; Nuimura, T.; Komori, J.; Takenaka, S.; Tshering, P.

    2012-04-01

    A number of supraglacial lakes formed on the termini of debris-covered glaciers in the Bhutan Himalaya as a result of glacier retreat due to climate change. The terminal part of the lake-terminating glaciers flow faster than that of the land-terminating glaciers because the basal ice motion is enhanced by high subglacial water pressure generated by lake water. Increased ice flux caused by the accelerated glacier flow could be dissipated through the calving process which reduced the glacier thickness. It is important to understand the interaction between lake formation and glacier dynamics. Although glacier flow velocity has been measured by remote-sensing analysis in several regions of the Himalayas, glacier thinning rates have not been observed by neither in-situ nor remote-sensing approaches. The lack of field data raises limitation to interpretations for glacier dynamics. We investigate the influence of the presence/absence of glacial lakes on glacier dynamics and changes in surface elevation. We study two debris-covered glaciers in the Lunana region, the Bhutan Himalaya. Thorthormi Glacier is a land-terminating glacier with some supraglacial lakes while Lugge Glacier is a lake-terminating glaciers. We surveyed the surface elevation of debris-covered areas of the two glaciers in 2004 and 2011 by a differential GPS. Change in surface elevation of the lake-terminating Lugge Glacier (-5.4--2.4 m yr-1) was much more negative than that of the land-terminating Thorthormi Glacier (-3.3-0.6 m yr-1). Surface flow speed of the Thorthormi Glacier measured during 2002-2004 was faster in the upper reaches (~90 m yr-1) and reduced toward the downstream (40 m yr-1). In contrast, the surface flow speed at the Lugge Glacier measured in the same periods was 40-55 m yr-1 and the greatest at the lower most part. Observed spatial distribution of surface flow velocity at both glaciers were evaluated by a two-dimensional numerical flow model. Calculated emergence velocities are 1

  9. Water, ice, and meteorological measurements at South Cascade glacier, Washington, balance year 2003

    Science.gov (United States)

    Bidlake, William R.; Josberger, Edward G.; Savoca, Mark E.

    2005-01-01

    Winter snow accumulation and summer snow and ice ablation were measured at South Cascade Glacier, Washington, to estimate glacier mass-balance quantities for balance year 2003. The 2003 glacier-average maximum winter snow balance was 2.66 meters water equivalent, which was about equal to the average of such balances for the glacier since balance year 1959. The 2003 glacier summer balance (-4.76 meters water equivalent) was the most negative reported for the glacier, and the 2003 net balance (-2.10 meters water equivalent), was the second-most negative reported. The glacier 2003 annual (water year) balance was -1.89 meters water equivalent. The area of the glacier near the end of the balance year was 1.89 square kilometers, a decrease of 0.03 square kilometer from the previous year. The equilibrium-line altitude was higher than any part of the glacier; however, because snow remained along part of one side of the upper glacier, the accumulation-area ratio was 0.07. During September 13, 2002-September 13, 2003, the glacier terminus retreated at a rate of about 15 meters per year. Average speed of surface ice, computed using a series of vertical aerial photographs dating back to 2001, ranged from 2.2 to 21.8 meters per year. Runoff from the subbasin containing the glacier and from an adjacent non-glacierized basin was gaged during part of water year 2003. Air temperature, precipitation, atmospheric water-vapor pressure, wind speed, and incoming solar radiation were measured at selected locations on and near the glacier. Summer 2003 at the glacier was among the warmest for which data are available.

  10. Polymer solidification of mixed wastes at the Rocky Flats Plant

    International Nuclear Information System (INIS)

    Faucette, A.M.; Logsdon, B.W.; Lucerna, J.J.; Yudnich, R.J.

    1994-01-01

    The Rocky Flats Plant is pursuing polymer solidification as a viable treatment option for several mixed waste streams that are subject to land disposal restrictions within the Resource Conservation and Recovery Act provisions. Tests completed to date using both surrogate and actual wastes indicate that polyethylene microencapsulation is a viable treatment option for several mixed wastes at the Rocky Flats Plant, including nitrate salts, sludges, and secondary wastes such as ash. Treatability studies conducted on actual salt waste demonstrated that the process is capable of producing waste forms that comply with all applicable regulatory criteria, including the Toxicity Characteristic Leaching Procedure. Tests have also been conducted to evaluate the feasibility of macroencapsulating certain debris wastes in polymers. Several methods and plastics have been tested for macroencapsulation, including post-consumer recycle and regrind polyethylene

  11. Implementing DOE guidance for hazards assessments at Rocky Flats Plant

    International Nuclear Information System (INIS)

    Zimmerman, G.A.

    1993-01-01

    Hazards Assessments are performed for a variety of activities and facilities at Rocky Flats Plant. Prior to 1991, there was no guidance for performing Hazards Assessments. Each organization that performed Hazards Assessments used its own methodology with no attempt at standardization. In 1991, DOE published guidelines for the performance of Hazards Assessments for Emergency Planning (DOE-EPG-5500.1, ''Guidance for a Hazards Assessment Methodology''). Subsequently, in 1992, DOE published a standard for the performance of Hazards Assessments (DOE-STD-1027-92, ''Hazard Categorization and Accident Analysis, Techniques for Compliance with DOE Order 5480.23, Nuclear Safety Analysis Reports''). Although these documents are a step in the direction of standardization, there remains a great deal of interpretation and subjective implementation in the performance of Hazards Assessments. Rocky Flats Plant has initiated efforts to develop a uniform and standard process to be used for Hazards Assessments

  12. Actinide solution processing at the Rocky Flats Environmental Technology Site

    International Nuclear Information System (INIS)

    1995-04-01

    The Department of Energy (DOE) has prepared an Environmental Assessment (EA), DOE/EA-1039, for radioactive solution removal and processing at Rocky Flats Environmental Technology Site, Golden, Colorado. The proposal for solution removal and processing is in response to independent safety assessments and an agreement with the State of Colorado to remove mixed residues at Rocky Flats and reduce the risk of future accidents. Monthly public meetings were held during the scoping and preparation of the EA. The scope of the EA included evaluations of alternative methods and locations of solution processing. A comment period from February 20, 1995 through March 21, 1995 was provided to the public and the State of Colorado to offer written comment on the EA. Comments were received from the State of Colorado and the U.S. Environmental Protection Agency. A response to the agency comments is included in the Final EA

  13. Facility overview for commercial application of selected Rocky Flats facilities

    International Nuclear Information System (INIS)

    1996-11-01

    The purpose of this Facility Overview is to support the Rocky Flats Local Impacts Initiative's Request for Interest, to solicit interest from commercial corporations for utilizing buildings 865 and 883, and the equipment contained within each building, for a commercial venture. In the following sections, this document describes the Rocky Flats Site, the buildings available for lease, the equipment within these buildings, the site services available to a tenant, the human resources available to support operations in buildings 865 and 883, and the environmental condition of the buildings and property. In addition, a brief description is provided of the work performed to date to explore the potential products that might be manufactured in Buildings 865 and 883, and the markets for these products

  14. Chernobyl - a Canadian technical perspective

    International Nuclear Information System (INIS)

    Howieson, J.Q.; Snell, V.G.

    1987-01-01

    In this report we present the design review done to date in Canada by AECL. From the Canadian point of view it covers: 1) relevant information on the Chernobyl design and the accident, both as presented by the Soviets at the Post-Accident Review Meeting (PARM) held in Vienna from August 25-29, 1986, and as deduced from publicly available Soviet documentation; and 2) details of AECL's technical review of the CANDU PHWR (Pressurized Heavy Water Reactor) against the background of the Chernobyl accident, and implications of the Chernobyl accident. Reviews of operational aspects are underway by the Canadian electrical utilities and a review by the Canadian regulatory agency (the Atomic Energy Control Board) is near completion

  15. Responsible Canadian energy progress report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The Canadian Association of Petroleum Producers (CAPP) represents oil and gas companies throughout Canada; its members produce over 90% of Canada's natural gas and crude oil output. The aim of the Association is to improve the economics of the Canadian upstream petroleum sector in an environmentally and socially responsible way. The aim of this Responsible Canadian Energy report is to present the performance data of CAPP's members for the year 2009. Data, trends, and performance analyses are provided throughout the document. This analysis makes it possible to determine where progress has been made and where performance improvement is necessary. It also presents success stories and best practices so that other companies can learn from them how to improve their own performance. This paper provides useful information on the performance of the upstream petroleum industry in Canada and highlights where the focus should be for further improvement in its performance.

  16. Political Socialization Research and Canadian Studies

    Science.gov (United States)

    Tomkins, George S.

    1977-01-01

    Presents a review of the burgeoning field of Canadian political socialization research as it applies to children and youth, and considers some implications of recent findings for the Canadian studies curriculum. (Editor)

  17. Research Awards: Canadian Partnerships Program Deadline: 12 ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Jean-Claude Dumais

    2012-09-12

    Sep 12, 2012 ... IDRC's Canadian Partnerships (CP) Program offers a Research ... For this, they may consider quantitative and qualitative methods, case studies, ... What types of processes do Canadian organizations use to learn about their ...

  18. Quantitative respirator man-testing at Rocky Flats

    International Nuclear Information System (INIS)

    Leigh, J.D.

    The dioctyl phthalate quantitative respirator man-testing method used at Rocky Flats is outlined. Using this method, 93 persons trained to use self contained breathing equipment were tested with eight respiratory protective devices. Test results obtained with the seven devices using high efficiency particulate filters are compared to the results obtained with the self contained breathing equipment. Also comparison is made for these results to test results for 1667 other employees

  19. Restoration of genetic connectivity among Northern Rockies wolf populations.

    Science.gov (United States)

    Hebblewhite, Mark; Musiani, Marco; Mills, L Scott

    2010-10-01

    Probably no conservation genetics issue is currently more controversial than the question of whether grey wolves (Canis lupus) in the Northern Rockies have recovered to genetically effective levels. Following the dispersal-based recolonization of Northwestern Montana from Canada, and reintroductions to Yellowstone and Central Idaho, wolves have vastly exceeded population recovery goals of 300 wolves distributed in at least 10 breeding pairs in each of Wyoming, Idaho and Montana. With >1700 wolves currently, efforts to delist wolves from endangered status have become mired in legal battles over the distinct population segment (DPS) clause of the Endangered Species Act (ESA), and whether subpopulations within the DPS were genetically isolated. An earlier study by vonHoldt et al. (2008) suggested Yellowstone National Park wolves were indeed isolated and was used against delisting in 2008. Since then, wolves were temporarily delisted, and a first controversial hunting season occurred in fall of 2009. Yet, concerns over the genetic recovery of wolves in the Northern Rockies remain, and upcoming District court rulings in the summer of 2010 will probably include consideration of gene flow between subpopulations. In this issue of Molecular Ecology, vonHoldt et al. (2010) conduct the largest analysis of gene flow and population structure of the Northern Rockies wolves to date. Using an impressive sampling design and novel analytic methods, vonHoldt et al. (2010) show substantial levels of gene flow between three identified subpopulations of wolves within the Northern Rockies, clarifying previous analyses and convincingly showing genetic recovery. © 2010 Blackwell Publishing Ltd.

  20. Rocky Flats Plant Site Environmental Report: 1993 Highlights

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    The Rocky Flats Plant Site Environmental Report provides summary information on the plant`s environmental monitoring programs and the results recorded during 1993. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population. This section provides an overview of these topics and summarizes more comprehensive discussions found in the main text of this annual report.

  1. Properties of vitrified rocky flats TRUW with different waste loadings

    International Nuclear Information System (INIS)

    Eddy, T.L.; Sears, J.W.; Grandy, J.D.; Miley, D.V.; Erickson, A.W.; Farnsworth, R.N.; Larsen, E.D.

    1994-01-01

    Leach rates, phase structures, and mechanical properties of simulated Rocky Flats Plant 1st and 2nd slate sludge vitrified in an arc melter are described as a function of waste to soil fraction and method of devitrification to produce the glass-ceramic waste form. Volatile, hazardous, and transuranic (TRU) surrogate metals were added to assess dissolution effects. Zirconia and titania were also added to confirm their ability as transuranic-surrogate getters

  2. Impacts and effects of ocean warming on intertidal rocky habitats

    OpenAIRE

    Hawkins, Stephen J.; Evans, A J; Firth, L B; Genner, Martin J; Herbert, R J H; Adams, L C; Moore, P J; Mieszkowska, N; Thompson, R.C.; Burrows, M.T.; Fenberg, P.B.

    2016-01-01

    • Intertidal rocky habitats comprise over 50% of the shorelines of the world, supporting a diversity of marine life and providing extensive ecosystem services worth in the region of US$ 5-10 trillion per year. • They are valuable indicators of the impacts of climate change on the wider marine environment and ecosystems. • Changes in species distributions, abundance and phenology have already been observed around the world in response to recent rapid climate change. • Species-level responses w...

  3. Reseeding of mussels on denuded rocky shores: preliminary studies ...

    African Journals Online (AJOL)

    A method is developed to establish clumps of mussels Perna perna in denuded areas on high-energy rocky shores on the south-east coast of South Africa. A total of 20 small (20–30 mm total length) mussels is placed under a 30 cm half-section of perforated PVC drainage pipe bolted to the rock surface. The pipe is left in ...

  4. Quantitative respirator man-testing at Rocky Flats

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, J. D.

    1978-01-01

    The dioctyl phthalate quantitative respirator man-testing method used at Rocky Flats is outlined. Using this method, 93 persons trained to use self contained breathing equipment were tested with eight respiratory protective devices. Test results obtained with the seven devices using high efficiency particulate filters are compared to the results obtained with the self contained breathing equipment. Also comparison is made for these results to test results for 1667 other employees.

  5. Rocky Flats Plant Site Environmental Report: 1993 Highlights

    International Nuclear Information System (INIS)

    1993-01-01

    The Rocky Flats Plant Site Environmental Report provides summary information on the plant's environmental monitoring programs and the results recorded during 1993. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population. This section provides an overview of these topics and summarizes more comprehensive discussions found in the main text of this annual report

  6. Immune Thrombocytopenia as a Consequence of Rocky Mountain Spotted Fever

    OpenAIRE

    Baldeo, Cherisse; Seegobin, Karan; Zuberi, Lara

    2017-01-01

    Primary immune thrombocytopenia (ITP) – also called idiopathic thrombocytopenic purpura or immune thrombocytopenic purpura – is an acquired thrombocytopenia caused by autoantibodies against platelet antigens. It is one of the more common causes of thrombocytopenia in otherwise asymptomatic adults. Rocky Mountain spotted fever (RMSF) is a potentially lethal, but curable, tick-borne disease. We present a case of ITP that was triggered by RMSF.

  7. Immune Thrombocytopenia as a Consequence of Rocky Mountain Spotted Fever

    Directory of Open Access Journals (Sweden)

    Cherisse Baldeo

    2017-10-01

    Full Text Available Primary immune thrombocytopenia (ITP – also called idiopathic thrombocytopenic purpura or immune thrombocytopenic purpura – is an acquired thrombocytopenia caused by autoantibodies against platelet antigens. It is one of the more common causes of thrombocytopenia in otherwise asymptomatic adults. Rocky Mountain spotted fever (RMSF is a potentially lethal, but curable, tick-borne disease. We present a case of ITP that was triggered by RMSF.

  8. Rocky Mountain spotted fever acquired in Florida, 1973-83.

    Science.gov (United States)

    Sacks, J J; Janowski, H T

    1985-01-01

    From 1973 to 1983, 49 Florida residents were reported with confirmed Rocky Mountain spotted fever (RMSF), 25 of whom were considered to have had Florida-acquired disease. Although there was no history of tick exposure for six of these 25 persons, all had contact with dogs or outdoor activities during the incubation period. The tick vectors of RMSF are widely distributed throughout Florida. We conclude that RMSF, although rare in Florida, can be acquired in the state. PMID:4061716

  9. DOE awards first economic conversion project at Rocky Flats

    International Nuclear Information System (INIS)

    Lobsenz, G.

    1993-01-01

    In the first economic conversion project at an Energy Department weapons facility, a Colorado company this week was given permission to refurbish four buildings at DOE's Rocky Flats plant to recycle slightly radioactive scrap metal. DOE, acting in conjunction with the Environmental Protection Agency and Colorado authorities, announced Tuesday it had given the go-ahead to Manufacturing Sciences Corp. of Golden, Colorado, to proceed with planning for the project

  10. Treatment of pond sludge at the Rocky Flats Plant

    International Nuclear Information System (INIS)

    Wienand, J.; Tyler, R.; Baldwin, C.

    1992-01-01

    The treatment of low-level radioactive/hazardous materials sludges from five inactive solar evaporation settling ponds at the Rocky Flats Plant is discussed. The paper presents information on the following topics: history of the ponds; previous pond cleanout activities; current approach to the problem with respect to water management, sludge management, regulatory actions, and disposal; and future processing technology needs in the areas of polymer solidification, microwave solidification, joule-heated glass melters, and advanced technology incineration

  11. Litigation Technical Support and Services, Rocky Mountain Arsenal

    Science.gov (United States)

    1989-05-01

    34 d V) W C > - d) 4- -~ 0 - - .4 ..- di L *..L 3~1 3-~ v mi a- a t - --- w- Vdi 4 - ý 0 -4 0 m~ -j m0 m’ .- us 0 Ill i to -v .4 I 4 1 t A ~ 3Ul t -4...2060. Marlow, D. J. 1979g, November 8. Pest control report, October 1979. Rocky Mountain Arsenal. Microfilm RMA182, Franes 2048 -2053 Marlow, D. J

  12. Photogrammetry on glaciers: Old and new knowledge

    Science.gov (United States)

    Pfeffer, W. T.; Welty, E.; O'Neel, S.

    2014-12-01

    In the past few decades terrestrial photogrammetry has become a widely used tool for glaciological research, brought about in part by the proliferation of high-quality, low-cost digital cameras, dramatic increases in image-processing power of computers, and very innovative progress in image processing, much of which has come from computer vision research and from the computer gaming industry. At present, glaciologists have developed their capacity to gather images much further than their ability to process them. Many researchers have accumulated vast inventories of imagery, but have no efficient means to extract the data they desire from them. In many cases these are single-image time series where the processing limitation lies in the paucity of methods to obtain 3-dimension object space information from measurements in the 2-dimensional image space; in other cases camera pairs have been operated but no automated means is in hand for conventional stereometric analysis of many thousands of image pairs. Often the processing task is further complicated by weak camera geometry or ground control distribution, either of which will compromise the quality of 3-dimensional object space solutions. Solutions exist for many of these problems, found sometimes among the latest computer vision results, and sometimes buried in decades-old pre-digital terrestrial photogrammetric literature. Other problems, particularly those arising from poorly constrained or underdetermined camera and ground control geometry, may be unsolvable. Small-scale, ground-based photography and photogrammetry of glaciers has grown over the past few decades in an organic and disorganized fashion, with much duplication of effort and little coordination or sharing of knowledge among researchers. Given the utility of terrestrial photogrammetry, its low cost (if properly developed and implemented), and the substantial value of the information to be had from it, some further effort to share knowledge and methods

  13. Sudden increase in tidal response linked to calving and acceleration at a large Greenland outlet glacier

    DEFF Research Database (Denmark)

    de Juan, Julia; Elósegui, Pedro; Nettles, Meredith

    2010-01-01

    strongly with the step-like increases in glacier speed and longitudinal strain rate associated with glacial earthquakes. The enhanced response to the ocean tides may be explained by a temporary disruption of the subglacial drainage system and a concomitant reduction of the friction at the ice......Large calving events at Greenland's largest outlet glaciers are associated with glacial earthquakes and near-instantaneous increases in glacier flow speed. At some glaciers and ice streams, flow is also modulated in a regular way by ocean tidal forcing at the terminus. At Helheim Glacier, analysis...

  14. Ethno-linguistic peculiarities of French Canadian and English ...

    African Journals Online (AJOL)

    When English Canadian and French Canadian phraseology is compared, the greater role of religion in the French Canadian community is evident, rather than in English Canadian; the influence of the Canadian variant of the English language on the Canadian variant of French is clearly expressed. With all the differences, ...

  15. Transnational archives: the Canadian case

    Directory of Open Access Journals (Sweden)

    Julia Creet

    2011-05-01

    Full Text Available This paper is a brief overview of the concept of the transnational archive as a counterpoint to the idea that a national archive is necessarily a locus of a static idea of nation. The Canadian national archives is used as a case study of an archives that was transnational in its inception, and one that has continued to change in its mandate and materials as a response to patterns in migration and changing notions of multiculturalism as a Canadian federal policy. It introduces the most recent formation of the transnational archive and its denizens: the genealogical archive inhabited by family historians.

  16. Canadian attitudes to nuclear power

    International Nuclear Information System (INIS)

    Davies, J.E.O.; Dobson, J.K.; Baril, R.G.

    1977-05-01

    A national assessment was made of public attitudes towards nuclear power, along with regional studies of the Maritimes and mid-western Canada and a study of Canadian policy-makers' views on nuclear energy. Public levels of knowledge about nuclear power are very low and there are marked regional differences. Opposition centers on questions of safety and is hard to mollify due to irrational fear and low institutional credibility. Canadians rate inflation as a higher priority problem than energy and see energy shortages as a future problem (within 5 years) and energy independence as a high priority policy. (E.C.B.)

  17. Issues in Canadian LLRW management

    International Nuclear Information System (INIS)

    Charlesworth, D.H.

    1988-01-01

    Some of the issues which are of concern in Canada are similar to those being discussed in the US because Canadian low-level radioactive waste (LLRW) production is similar in quantity and characteristics to that which will be handled by some state compacts. This paper gives a Canadian viewpoint of: the choice between interim storage and permanent disposal; the importance of considering inadvertent intrusion; the role of waste categorization and stability; and the concerns in assessing disposal performance. The discussion is related to Atomic Energy of Canada Limited's LLRW disposal program, and its approach to resolving these issues

  18. The rocky flats controversy on radionuclide soil action levels

    International Nuclear Information System (INIS)

    Earle, T.C.

    2004-01-01

    An account of the Rocky Flats radionuclide soil action level controversy is presented as: a case study for the purpose of understanding the nature and value of stakeholder involvement in the management of radiological hazards. The report consists of three main sections. The first section outlines the Rocky Flats story, including the Cold War era, which was characterised by secrecy and distrust, the post-Cold War era, in which trust and co-operation between risk managers and the public began to develop. This contrast between these two historical periods provides the context necessary to understand the radionuclide soil action level controversy, the main events of which are described in the second section. In the final section, the Rocky Flats case is briefly discussed within the framework of a general model of stakeholder involvement and the lessons learned from the case are identified: (1) without a basis in shared values, collaborative public involvement in the management of radiological hazards is not possible; (2) given a basis in shared values, collaborative public involvement can lead to improved solutions to the management of radiological hazards; and (3) risk managers should therefore seek to understand the values of public stakeholders and to identify ways, through stakeholder involvement, that those values can be incorporated in management practice. (author)

  19. Mortality among plutonium and other workers at Rocky Flats

    International Nuclear Information System (INIS)

    Wilkinson, G.S.; Acquavella, J.F.; Reyes, M.; Tietjen, G.L.; Wiggs, L.d.; Voelz, G.L.

    1985-01-01

    A detailed study of mortality and radiation exposure for Rocky Flats workers was reported at the Sixteenth Mid-Year Topical Symposium of the Health Physics Society in January 1983. Significantly fewer deaths were found than were expected due to all causes, all malignant neoplasms, lung cancer, and cancer of the digestive organs. No bone cancers were observed and cancers commonly associated with radiation exposure were not more frequent than expected. Significantly more deaths than expected were observed for two causes, cancer of the prostate and benign and unspecified neoplasms. Further investigation revealed that the deaths from benign and unspecified neoplasms all involved intracranial tumors. A case control study found no association between these brain tumors and exposure to radiation, including plutonium depositions or type of occupation. The excess deaths from intracranial tumors remain unexplained but do not appear to be associated with employment at Rocky Flats. Relative risks among Rocky Flats workers with cumulative plutonium depositions of 2 nCi or more did not indicate a significantly greater risk of death among workers exposed to plutonium than among unexposed workers. Similar results were found for workers with cumulative radiation exposure of at least 1 rem. 2 references, 3 tables

  20. Rocky flats closure project - lessons learned in worker stakeholder engagement

    Energy Technology Data Exchange (ETDEWEB)

    Sweeney, Laura [Des Moines Area Community College, Ankeny, Iowa (United States); Mazur, Robert E. [Iowa State University, Ames, Iowa (United States); Edelson, Martin [Ames Laboratory-USDOE (Retired), Ames, Iowa (United States)

    2013-07-01

    The Rocky Flats Environmental Technology Site (EPA Superfund site near Denver, Colorado) produced plutonium components for nuclear weapons for the U.S. defense program. The facility shut down in 1989 and clean up began in 1992. To ensure safe remediation of inactive nuclear sites, site owners have begun to consult stakeholders more widely in recent years. The closure of Rocky Flats aimed to set the standard for stakeholder involvement in doing the work safely, complying with regulations/standards, in a cost-effective manner. We have studied, using ethnographic methods, the extent to which workers at Rocky Flats were involved in communication and decision making strategies. Our results point out that workers can have perceptions of the site remediation process that differ from management and even other workers and that a significant number of workers questioned the commitment by management to engage the worker as stakeholder. The most effective remediation efforts should involve careful consideration of the insights and observations of all workers, particularly those who face immediate and high-level health and safety risks. (authors)

  1. [Rocky Mountain spotted fever in an American tourist].

    Science.gov (United States)

    de Pender, A M G; Bauer, A G C; van Genderen, P J J

    2005-04-02

    In a 28-year-old male American tourist who presented in the hospital with fever, cold shivers, headache, nausea, myalgia and arthralgia, Rocky Mountain spotted fever was suspected, partly because he came from an endemic region (the state of Georgia). The patient was treated with doxycycline, 100 mg b.i.d.; 9 days after the first appearance of the symptoms, the diagnosis was confirmed by the report of a positive antibody titre against Rickettsia rickettsii. The patient did not have exanthema. He was discharged in good general condition after two weeks of treatment. Rocky Mountain spotted fever, caused by the Gram-negative bacterium R. rickettsii, is a serious rickettsiosis. The disease is seen only sporadically in the Netherlands because the ticks in the Netherlands do not carry the bacterium. The travel history is still not a standard component of the anamnesis and is therefore often forgotten. This can lead to under-diagnosis and delayed treatment of diseases that were formerly limited to the continent. The early recognition and treatment of Rocky Mountain spotted fever is important since delayed treatment is associated with a clear increase in both morbidity and mortality.

  2. Rocky Mountain spotted fever in Mexico: past, present, and future.

    Science.gov (United States)

    Álvarez-Hernández, Gerardo; Roldán, Jesús Felipe González; Milan, Néstor Saúl Hernández; Lash, R Ryan; Behravesh, Casey Barton; Paddock, Christopher D

    2017-06-01

    Rocky Mountain spotted fever, a tick-borne zoonosis caused by Rickettsia rickettsii, is among the most lethal of all infectious diseases in the Americas. In Mexico, the disease was first described during the early 1940s by scientists who carefully documented specific environmental determinants responsible for devastating outbreaks in several communities in the states of Sinaloa, Sonora, Durango, and Coahuila. These investigators also described the pivotal roles of domesticated dogs and Rhipicephalus sanguineus sensu lato (brown dog ticks) as drivers of epidemic levels of Rocky Mountain spotted fever. After several decades of quiescence, the disease re-emerged in Sonora and Baja California during the early 21st century, driven by the same environmental circumstances that perpetuated outbreaks in Mexico during the 1940s. This Review explores the history of Rocky Mountain spotted fever in Mexico, current epidemiology, and the multiple clinical, economic, and social challenges that must be considered in the control and prevention of this life-threatening illness. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Rocky flats closure project - lessons learned in worker stakeholder engagement

    International Nuclear Information System (INIS)

    Sweeney, Laura; Mazur, Robert E.; Edelson, Martin

    2013-01-01

    The Rocky Flats Environmental Technology Site (EPA Superfund site near Denver, Colorado) produced plutonium components for nuclear weapons for the U.S. defense program. The facility shut down in 1989 and clean up began in 1992. To ensure safe remediation of inactive nuclear sites, site owners have begun to consult stakeholders more widely in recent years. The closure of Rocky Flats aimed to set the standard for stakeholder involvement in doing the work safely, complying with regulations/standards, in a cost-effective manner. We have studied, using ethnographic methods, the extent to which workers at Rocky Flats were involved in communication and decision making strategies. Our results point out that workers can have perceptions of the site remediation process that differ from management and even other workers and that a significant number of workers questioned the commitment by management to engage the worker as stakeholder. The most effective remediation efforts should involve careful consideration of the insights and observations of all workers, particularly those who face immediate and high-level health and safety risks. (authors)

  4. Map of mixed prairie grassland vegetation, Rocky Flats, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Clark, S J.V.; Webber, P J; Komarkova, V; Weber, W A

    1980-01-01

    A color vegetation map at the scale of 1:12,000 of the area surrounding the Rocky Flats, Rockwell International Plant near Boulder, Colorado, provides a permanent record of baseline data which can be used to monitor changes in both vegetation and environment and thus to contribute to future land management and land-use policies. Sixteen mapping units based on species composition were identified, and characterized by two 10-m/sup 2/ vegetation stands each. These were grouped into prairie, pasture, and valley side on the basis of their species composition. Both the mapping units and these major groups were later confirmed by agglomerative clustering analysis of the 32 vegetation stands on the basis of species composition. A modified Bray and Curtis ordination was used to determine the environmental factor complexes controlling the distribution of vegetation at Rocky flats. Recommendations are made for future policies of environmental management and predictions of the response to environmental change of the present vegetation at the Rocky Flats site.

  5. Financial outlook for the Canadian gas industry

    International Nuclear Information System (INIS)

    Friedenberg, B.

    1995-01-01

    The financial outlook for the Canadian gas industry depends on the outlook for gas prices at Canadian producing basins, the cost of producing in Canada and the volume of production of Canadian natural gas. Price, cost and volume determine the health of the Canadian industry. Industry's costs are the basis of the supply (volume) offered on the market and price is determined by the interaction of supply and demand. (author)

  6. Canadian International Food Security Research Fund (CIFSRF ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Canadian International Food Security Research Fund (CIFSRF). The Canadian International Food Security Research Fund (CIFS-RF) is a collaborative program of the Canadian International Development Agency (CIDA) and IDRC valued at CA $61 654 707 (CIDA: CA $50 000 000; IDRC: CA $11 654 707). The program ...

  7. Storage and release of organic carbon from glaciers and ice sheets

    Science.gov (United States)

    Hood, Eran; Battin, Tom J.; Fellman, Jason; O'Neel, Shad; Spencer, Robert G. M.

    2015-02-01

    Polar ice sheets and mountain glaciers, which cover roughly 11% of the Earth's land surface, store organic carbon from local and distant sources and then release it to downstream environments. Climate-driven changes to glacier runoff are expected to be larger than climate impacts on other components of the hydrological cycle, and may represent an important flux of organic carbon. A compilation of published data on dissolved organic carbon from glaciers across five continents reveals that mountain and polar glaciers represent a quantitatively important store of organic carbon. The Antarctic Ice Sheet is the repository of most of the roughly 6 petagrams (Pg) of organic carbon stored in glacier ice, but the annual release of glacier organic carbon is dominated by mountain glaciers in the case of dissolved organic carbon and the Greenland Ice Sheet in the case of particulate organic carbon. Climate change contributes to these fluxes: approximately 13% of the annual flux of glacier dissolved organic carbon is a result of glacier mass loss. These losses are expected to accelerate, leading to a cumulative loss of roughly 15 teragrams (Tg) of glacial dissolved organic carbon by 2050 due to climate change -- equivalent to about half of the annual flux of dissolved organic carbon from the Amazon River. Thus, glaciers constitute a key link between terrestrial and aquatic carbon fluxes, and will be of increasing importance in land-to-ocean fluxes of organic carbon in glacierized regions.

  8. Storage and release of organic carbon from glaciers and ice sheets

    Science.gov (United States)

    Hood, Eran; Battin, Tom J.; Fellman, Jason; O'Neel, Shad; Spencer, Robert G. M.

    2015-01-01

    Polar ice sheets and mountain glaciers, which cover roughly 11% of the Earth's land surface, store organic carbon from local and distant sources and then release it to downstream environments. Climate-driven changes to glacier runoff are expected to be larger than climate impacts on other components of the hydrological cycle, and may represent an important flux of organic carbon. A compilation of published data on dissolved organic carbon from glaciers across five continents reveals that mountain and polar glaciers represent a quantitatively important store of organic carbon. The Antarctic Ice Sheet is the repository of most of the roughly 6 petagrams (Pg) of organic carbon stored in glacier ice, but the annual release of glacier organic carbon is dominated by mountain glaciers in the case of dissolved organic carbon and the Greenland Ice Sheet in the case of particulate organic carbon. Climate change contributes to these fluxes: approximately 13% of the annual flux of glacier dissolved organic carbon is a result of glacier mass loss. These losses are expected to accelerate, leading to a cumulative loss of roughly 15 teragrams (Tg) of glacial dissolved organic carbon by 2050 due to climate change — equivalent to about half of the annual flux of dissolved organic carbon from the Amazon River. Thus, glaciers constitute a key link between terrestrial and aquatic carbon fluxes, and will be of increasing importance in land-to-ocean fluxes of organic carbon in glacierized regions.

  9. Accessing the inaccessible: making (successful) field observations at tidewater glacier termini

    Science.gov (United States)

    Kienholz, C.; Amundson, J. M.; Jackson, R. H.; Motyka, R. J.; Nash, J. D.; Sutherland, D.

    2017-12-01

    Glaciers terminating in ocean water (tidewater glaciers) show complex dynamic behavior driven predominantly by processes at the ice-ocean interface (sedimentation, erosion, iceberg calving, submarine melting). A quantitative understanding of these processes is required, for example, to better assess tidewater glaciers' fate in our rapidly warming environment. Lacking observations close to glacier termini, due to unpredictable risks from calving, hamper this understanding. In an effort to remedy this lack of knowledge, we initiated a large field-based effort at LeConte Glacier, southeast Alaska, in 2016. LeConte Glacier is a regional analog for many tidewater glaciers, but better accessible and observable and thus an ideal target for our multi-disciplinary effort. Our ongoing campaigns comprise measurements from novel autonomous vessels (temperature, salinity and current) in the immediate proximity of the glacier terminus and additional surveys (including multibeam bathymetry) from boats and moorings in the proglacial fjord. These measurements are complemented by iceberg and glacier velocity measurements from time lapse cameras and a portable radar interferometer situated above LeConte Bay. GPS-based velocity observations and melt measurements are conducted on the glacier. These measurements provide necessary input for process-based understanding and numerical modeling of the glacier and fjord systems. In the presentation, we discuss promising initial results and lessons learned from the campaign.

  10. Climatic Drivers of Tropical Andean Glacier Recession, c1987 - c2006

    Science.gov (United States)

    Slayback, D. A.; Tucker, C. J.

    2011-12-01

    We report on the climatic trends associated with glacier recession in the tropical Andes from the mid-1980s to the mid-2000s. These glaciers comprise 99% of the world's tropical glaciers and occur in Bolivia, Peru, Ecuador, Colombia, and Venezuela. We previously reported on our comprehensive analysis of Landsat imagery of these glaciers, which indicated an overall recession of approximately 30% in glacierized area between c1987 and c2006, or a drop from ~2500 km2 to ~1800 km2 in total glacier area. In the current work, we have examined trends in temperature, cloud cover, and precipitation and compared these trends with those in glacier recession. For temperature and cloud cover, we use the MERRA reanalysis datasets (Modern Era Retrospective-Analysis for Research and Applications) produced by the NASA Goddard's GMAO (Global Modeling and Assimilation Office), which are based on satellite observations. For precipitation, we use the GPCP (Glocal Precipitation Climatology Project) datasets, which are based on both ground and satellite observations. We find that over the glacierized zones, the only significant trends are those in temperature, which show increases of up to 0.5 degree C per decade over some glacierized areas. Trends in cloud cover and precipitation are not generally significant. We discuss these trends in relation to glacier recession trends for each of the major glacierized areas of the tropical Andes.

  11. Changes of glacier, glacier-fed rivers and lakes in Altai Tavan Bogd National Park, Western Mongolia, based on multispectral satellite data from 1990 to 2017

    Science.gov (United States)

    Batsaikhan, B.; Lkhamjav, O.; Batsaikhan, N.

    2017-12-01

    Impacts on glaciers and water resource management have been altering through climate changes in Mongolia territory characterized by dry and semi-arid climate with low precipitation. Melting glaciers are early indicators of climate change unlike the response of the forests which is slower and takes place over a long period of time. Mountain glaciers are important environmental components of local, regional, and global hydrological cycles. The study calculates an overview of changes for glacier, glacier-fed rivers and lakes in Altai Tavan Bogd mountain, the Western Mongolia, based on the indexes of multispectral data and the methods typically applied in glacier studies. Were utilized an integrated approach of Normalized Difference Snow Index (NDSI) and Normalized Difference Water Index (NDWI) to combine Landsat, MODIS imagery and digital elevation model, to identify glacier cover are and quantify water storage change in lakes, and compared that with and climate parameters including precipitation, land surface temperature, evaporation, moisture. Our results show that melts of glacier at the study area has contributed to significantly increase of water storage of lakes in valley of The Altai Tavan Bogd mountain. There is hydrologic connection that lake basin is directly fed by glacier meltwater.

  12. Glacialmorphological reconstruction of glacier advances and glacial lake outburst floods at the Cachapoal glacier in the Dry Central Andes of Chile (34°S)

    Science.gov (United States)

    Iturrizaga, Lasafam; Charrier, Reynaldo

    2013-04-01

    Throughout the Andes Mountain range of South America a general trend of glacier shrinkage has taken place in the last century. Only a few glaciers have shown a rather non-continuous trend of glacier retreat and temporally advanced or even surged during the mid-19th to 20th century. One of the earliest assumed glacier surges has occurred in the upper Cachapoal catchment area at the homonymous glacier. In climatic respect the Cachapoal glacier is located in the transition zone from the most southern part of the Dry Central Andes of Chile to the more humid zone of the Wet Andes. The region is affected mainly by winter precipitation deriving from the Westerlies. The debris-covered, 12 km-long Cachapoal glacier represents one of the largest valley glaciers in the Central Andes. It is an avalanche-fed glacier with an almost 1500 m-high head wall in its upper catchment area flowing down from Picos del Barroso (5180 m) and terminates at an elevation of 2630 m a.s.l. with a bifurcated glacier tongue. A large moraine complex, almost 2 km in length and 500 m in width, separates the two glacier lobes. During times of advanced glacier tongue positions the Ríos Molina and Cachapoal may be have blocked independently at two distinct localities which are situated about 2300 m apart from each other. A blockage with temporal lake formation has occurred at least in the years 1848, 1955 and 1981 (cf. Plagemann 1887, Peña 1981), from which the rupture of the earliest glacier barrier has been the most devastating. This event is locally reminded as "la gran avenida en seco" in the historical record. Geomorphological evidence of the past historical and modern glacier expansions is given in the proglacial area by a fresh dead-ice hummocky topography and glacial trimlines at the valley flanks. More down valley broad outwash plains and boulder clusters indicate past high energy floods produced by glacier lake outbursts. Regarding the small size of the catchment area of the Río Molina

  13. Glaciers in South Tyrol 1850 - 2006: application of Airborne Laser Scanner data, orthophotos and historical maps for the acquisition of recent and the reconstruction of past glacier extents

    International Nuclear Information System (INIS)

    Knoll, C. C.

    2009-01-01

    In the densely populated high mountain areas of the Alps, glaciers are an important part of the cultural and natural landscape. During the warm summer months they are among the most important freshwater resources for economy sectors such as agriculture or industry, an important component for the tourism industry and of great significance for the production of energy from hydropower. However, they also constitute a potential cause of natural hazards. Due to their direct linkage to temperature and precipitation, glaciers are characterized as one of the best natural climate indicators. For that reason, mountain glaciers have become a key symbol for the ongoing discussion about climate, climate changes and the resulting consequences because their reactions can easily be observed and visualized. The main objective of this doctoral thesis is to contribute to a better understanding of the regional South Tyrolean glacier development through a reconstruction and analysis of the glacier changes that have occurred since the climax of the Little Ice Age at around 1850. Glacier inventories, fieldwork and GIS-assisted reconstructions of historical and calculation of recent glacier topographies are used to depict, analyze and visualize the changes of the South Tyrolean glaciers between the maximum extent of approximately 1850 and the inventories of 1997 and 2006. In a comparison of recent, highly accurate glacier topographies mapped with ALS-methods (Airborne Laser Scanner) with a reconstruction of the Little Ice Age maximum South Tyrolean glaciers were detected to have lost 183.2 km 2 or 66% of their glacier cover in approximately the last 150 years. This comparison also showed a loss in glacier volume of 9 km 3 between 1850 and 2006, which corresponds to a mean ice thickness change of -49 m. These drastic losses in the glacier covered area and volume, which are mainly visible on the glacier tongues of large valley glaciers like Langtauferer- and Suldenferner, clearly show

  14. Climate, glacier mass balance and runoff (1993-2005) for the Mittivakkat Glacier catchment, Ammassalik Island, SE Greenland, and in a long term perspective (1898-1993)

    DEFF Research Database (Denmark)

    Mernild, Sebastian H.; Kane, D.L.; Hansen, Birger

    2008-01-01

    temperatures (MAAT) occur in the coastal area, indicating an approximately 20-d shorter thawing period. The higher lying glacier area, in contrast, experiences an increasing MAAT, an approximately 40-d longer thawing period and a 60-d longer snow-free period. The Mittivakkat Glacier net mass balance has been...... almost continuously negative, corresponding to an average loss of glacier volume of 0.4% yr-1. The total catchment runoff is averaging 1973±281 mm w.eq. yr-1, and around 30% of the runoff is explained by glacier net loss. Over the 106 years (1898-2004) MAAT has, on average, increased significantly...

  15. Changing drainage patterns within South Cascade Glacier, Washington, USA, 1964-1992

    Science.gov (United States)

    Fountain, A.G.; Vaughn, B.H.

    1995-01-01

    The theoretical patterns of water drainage are presented for South Cascade Glacier for four different years between 1964 and 1992, during which the glacier was thinning and receding. The theoretical pattern compares well, in a broad sense, with the flow pattern determined from tracer injections in 1986 and 1987. Differences between the patterns may result from the routing of surface meltwater in crevasses prior to entering the body of the glacier. The changing drainage pattern was caused by glacier thinning. The migration of a drainage divide eventually rerouted most of the surface meltwater from the main stream that drained the glacier in 1987 to another, formerly smaller, stream by 1992. On the basis of projected glacier thinning between 1992 and 1999, we predict that the drainage divide will continue to migrate across the glacier.

  16. Glacier protection laws: Potential conflicts in managing glacial hazards and adapting to climate change.

    Science.gov (United States)

    Anacona, Pablo Iribarren; Kinney, Josie; Schaefer, Marius; Harrison, Stephan; Wilson, Ryan; Segovia, Alexis; Mazzorana, Bruno; Guerra, Felipe; Farías, David; Reynolds, John M; Glasser, Neil F

    2018-03-13

    The environmental, socioeconomic and cultural significance of glaciers has motivated several countries to regulate activities on glaciers and glacierized surroundings. However, laws written to specifically protect mountain glaciers have only recently been considered within national political agendas. Glacier Protection Laws (GPLs) originate in countries where mining has damaged glaciers and have been adopted with the aim of protecting the cryosphere from harmful activities. Here, we analyze GPLs in Argentina (approved) and Chile (under discussion) to identify potential environmental conflicts arising from law restrictions and omissions. We conclude that GPLs overlook the dynamics of glaciers and could prevent or delay actions needed to mitigate glacial hazards (e.g. artificial drainage of glacial lakes) thus placing populations at risk. Furthermore, GPL restrictions could hinder strategies (e.g. use of glacial lakes as reservoirs) to mitigate adverse impacts of climate change. Arguably, more flexible GPLs are needed to protect us from the changing cryosphere.

  17. Dendrochronology and late Holocene history of Bering piedmont glacier, Alaska

    Science.gov (United States)

    Wiles, G.C.; Post, A.; Muller, E.H.; Molnia, B.F.

    1999-01-01

    Fluctuations of the piedmont lobe of Bering Glacier and its sublobe Steller Glacier over the past two millennia are reconstructed using 34 radiocarbon dates and tree-ring data from 16 sites across the glaciers' forelands. The general sequence of glacial activity is consistent with well-dated fluctuations of tidewater and land-terminating glaciers elsewhere along the Gulf of Alaska. Extensive forested areas along 25 km of the Bering ice margin were inundated by glacio-lacustrine and glacio-fluvial sediments during a probable ice advance shortly before 500 cal yr A.D. Regrowth of forests followed the retreating ice as early as the 7th century A.D., with frequent interruptions of tree growth due to outwash aggradation. Forests overrun by ice and buried in outwash indicate readvance about 1080 cal yr A.D. Retreat followed, with ice-free conditions maintained along the distal portions of the forefield until the early 17th century after which the ice advanced to within a few kilometers of its outer Neoglacial moraine. Ice reached this position after the mid-17th century and prior to 200 yr ago. Since the early 20th century, glacial retreat has been punctuated by periodic surges. The record from forests overrun by the nonsurging Steller Lobe shows that this western ice margin was advancing by 1250 A.D., reaching near its outer moraine after 1420 cal yr A.D. Since the late 19th century, the lobe has dominantly retreated.

  18. Reconstruction of specific mass balance for glaciers in Western ...

    Indian Academy of Sciences (India)

    Seasonal sensitivity characteristics (SSCs) were developed for Naradu, Shaune Garang, Gor Garang and Gara glaciers, Western Himalaya to quantify the changes in mean specific mass balance using monthly temperature and precipitation perturbations. The temperature sensitivities were observed high during summer ...

  19. Landmark Study Reveals Antarctic Glacier's Long History of Retreat

    OpenAIRE

    Kuska, Dale M.

    2016-01-01

    Faculty Showcase Archive Article Approved for public release; distribution is unlimited. A major study, released in late November in the journal “Nature,” reveals the history of retreat of the massive Pine Island Glacier (PIG) in western Antarctica, widely considered one of the largest contributors to global sea-level rise.

  20. Reconstruction of specific mass balance for glaciers in Western ...

    Indian Academy of Sciences (India)

    Vinay Kumar Gaddam

    2017-06-12

    Jun 12, 2017 ... temperatures and precipitation estimates of ERA 20CM ensemble climate reanalysis datasets to reconstruct the specific mass balance for a period of 110 years, between 1900 and 2010. Mass balance estimates suggest that the Shaune Garang, Gor-Garang and Gara glaciers have experienced both ...

  1. A glacier runoff extension to the Precipitation Runoff Modeling System

    Science.gov (United States)

    Van Beusekom, Ashley E.; Viger, Roland

    2016-01-01

    A module to simulate glacier runoff, PRMSglacier, was added to PRMS (Precipitation Runoff Modeling System), a distributed-parameter, physical-process hydrological simulation code. The extension does not require extensive on-glacier measurements or computational expense but still relies on physical principles over empirical relations as much as is feasible while maintaining model usability. PRMSglacier is validated on two basins in Alaska, Wolverine, and Gulkana Glacier basin, which have been studied since 1966 and have a substantial amount of data with which to test model performance over a long period of time covering a wide range of climatic and hydrologic conditions. When error in field measurements is considered, the Nash-Sutcliffe efficiencies of streamflow are 0.87 and 0.86, the absolute bias fractions of the winter mass balance simulations are 0.10 and 0.08, and the absolute bias fractions of the summer mass balances are 0.01 and 0.03, all computed over 42 years for the Wolverine and Gulkana Glacier basins, respectively. Without taking into account measurement error, the values are still within the range achieved by the more computationally expensive codes tested over shorter time periods.

  2. Melting glaciers signal climate change in Bolivia | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-05-13

    May 13, 2011 ... Melting glaciers signal climate change in Bolivia ... Global warming is occurring faster at high altitudes, causing the ... and how the local environment was going to change in years to come. ... New economic opportunities and better transportation to markets in La Paz have brought migrants to the area.

  3. Modelling the dynamics and boundary processes of Svalbard glaciers

    NARCIS (Netherlands)

    van Pelt, W.J.J.

    2014-01-01

    The focus of this thesis is on improving our understanding of surface and basal processes in the context of glaciers in Svalbard. At the surface, interactions with the atmosphere and underlying snow determine the surface mass balance. A coupled model is applied to Nordenskiöldbreen, a tidewater

  4. Traileka Glacier X-Stack. Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Borkar, Shekhar [Intel Federal LLC, Fairfax, VA (United States)

    2015-09-01

    The XStack Traleika Glacier (XSTG) project was a three-year research award for exploring a revolutionary exascale-class machine software framework. The XSTG program, including Intel, UC San Diego, Pacific Northwest National Lab, UIUC, Rice University, Reservoir Labs, ET International, and U. Delaware, had major accomplishments, insights, and products resulting from this three-year effort.

  5. Glaciers et évolution climatique dans les Andes boliviennes. Glacier de Zongo et glacier de Chacaltaya Cordillère Royale, 16°S

    Directory of Open Access Journals (Sweden)

    1995-01-01

    Full Text Available SEDIMENTOLOGY OF THE HUANCANE FORMATION (NEOCOMIAN OF THE CUSCO REGION AND ITS RELATION TO SEA LEVEL VARIATIONS. The Huancane formation (Neocomian of the Cusco region is mainly composed of quartz sandstones which are deposited in fluvial environments. The facies recognized are organized in a vertical sequence: fluvial sheet sandstones, oxidized or eroded surface, the shale facies of alluvial plain and unusual limestone facies of possible marine origin. These vertical facies sequences show that eustatic sea level variations controlled the fluvial sedimentation. The rivers came from the NE and were fed by the erosion of the Brazilian Shield. The sedimentation developed above the boundary of the SW edge of the Eastern basin, and the Cusco-Puno Swell which had locale horst and grabens inherited from pre-neocomian relief. GLACIARES Y EVOLUCIÓN CLIMÁTICA EN LOS ANDES BOLIVIANOS GLACIAR DE ZONGO Y GLACIAR DE CHACALTAYA, CORDILLERA REAL, 16°S. Por su sensibilidad y su plazo de respuesta breve, el glaciar es de un gran interés para analizar la evolución y la variabilidad actuales del clima entre los trópicos. Se presentan los métodos de determinación del balance de masas y del balance hidrológico, con una frecuencia de mediciones mensual. Los resultados recogidos durante tres años (1991-1994 muestran una grande variabilidad. Ésta es controlada sobre todo por la extensión del periodo de precipitaciones en medio de la temporada cálida que dura más o menos 6 meses. Los eventos ENSO (El Niño Southern Oscillation son asociados a balances netamente negativos, lo que es demostrado por la respuesta del glaciar al episodio de 1991-1992 y por la reconstrucción de los balances efectuados en base a los datos hidrológicos durante los dos últimos decenios. El retroceso acelerado de los glaciares tropicales desde los años 1980 es vinculado a la vez a una sucesión de eventos ENSO y al recalentamiento atmosférico. GLACIERS AND CLIMATIC EVOLUTION IN

  6. Assessing Glacier Hazards At Ghiacciaio Del Belvedere, Macugnaga, Italian Alps

    Science.gov (United States)

    Haeberli, W.; Chiarle, M.; Mortara, G.; Mazza, A.

    The uppermost section of the Valle Anzasca behind and above the community of Macugnaga in the Italian Alps is one of the most spectacular high-mountain land- scapes in Europe, with gigantic rock walls and numerous steep hanging glaciers. Its main glacier, Ghiacciaio del Belvedere at the foot of the huge Monte Rosa east face, is a heavily debris-covered glacier flowing on a thick sediment bed. Problems with floods, avalanches and debris flows from this ice body have been known for extended time periods. Most recently, however, the evolution of this highly dynamic environ- ment has become more dramatic. An outburst of Lago delle Locce, an ice-dammed lake at the confluenec of the tributary Ghiacciaio delle Locce with Ghiacciaio del Belvedere, caused heavy damage in 1979 and necessitated site investigation and con- struction work to be done for flood protection. The intermittent glacier growth ten- dency in the 1970es induced strong bulging of the glacier surface and, in places, caused the glacier tongue to override historical morains and to destroy newly-grown forest stands. A surge-type flow acceleration started in the lower parts of the Monte- Rosa east face during summer 2000, leading to strong crevassing and deformation of Ghiacciaio del Belvedere and extreme bulging of its orographic right margin. High water pressure and accelerated movement lasted into winter 2001/2002: the ice now started overriding the LIA moraine near Rifugio Zamboni of the CAI. In addition but rather independently, a most active detachment zone for rock falls and debris flows developed for several years now in the east face of Monte Rosa, somewhat more to the south of the accelerated glacier movement and at an altitude where relatively warm permafrost must be expected. Besides the scientific interest in these phenomena, the growing hazard potential to the local infrastructure must be considered seriously. Es- pecially potentials for the destabilization of large rock and ice masses in the

  7. Inspection of Alpine glaciers with cosmic-ray muon radiography

    Science.gov (United States)

    Nishiyama, Ryuichi; Ariga, Akitaka; Ariga, Tomoko; Ereditato, Antonio; Lechmann, Alessandro; Mair, David; Scampoli, Paola; Schlunegger, Fritz; Vladymyrov, Mykhailo

    2016-04-01

    Radiography using cosmic-ray muons represents a challenging method for probing the bedrock topography beneath Alpine glaciers. We present the current status of our feasibility study at Eiger glacier, situated on the western flank of the Eiger in the Jungfrau region, Central Swiss Alps. The muon radiography is a technique that has been recently developed to investigate the internal density profiles of geoscientific targets. It is based on the measurement of the absorption of the cosmic-ray muons inside a material. Because the energy spectrum of cosmic-ray muons and the energy dependence of muon range have been studied well during the past years, the attenuation of the muon flux can be used to derive the column density, i.e. the density integrated along the muon trajectories, of geoscientific targets. This technique has recently been applied for non-invasive inspection of volcanoes, nuclear reactors, seismic faults, caves and etc. The greatest advantage of the method in the field of glacier studies is that it yields a unique solution of the density underneath a glacier without any assumption of physical properties inside the target. Large density contrasts, as expected between glacier ice (˜ 1.0g/cm3) and bedrock (˜ 2.5g/cm3), would allow us to elucidate the shape of the bedrock in high resolution. Accordingly, this technology will provide for the first time information on the bedrock surface beneath a steep and non-accessible Alpine glacier, in a complementary way with respect to other exploration methods (drilling, ground penetrating radar, seismic survey, gravity explorations and etc.). Our first aim is to demonstrate the feasibility of the method through a case study at the Eiger glacier, situated in the Central Swiss Alps. The Eiger glacier straddles the western flank of the Eiger between 3700 and 2300 m above sea level (a.s.l.). The glacier has shortened by about 150 m during the past 30 years in response to the ongoing global warming, causing a concern for

  8. Increased Melting of Glaciers during Cotopaxi volcano awakening in 2015

    Science.gov (United States)

    Ramon, Patricio; Vallejo, Silvia; Almeida, Marco; Gomez, Juan Pablo; Caceres, Bolivar

    2016-04-01

    Cotopaxi (5897 m), located about 50 km south of Quito (Ecuador), is one of the most active volcanoes in the Andes and its historical eruptions have caused a great impact on the population by the generation of lahars along its three main drainages (N, S, E). Starting on April 2015 the seismic monitoring networks and the SO2 gas detection network in May 2015 showed a significant increase from their background values, in June a geodetic instrument located in the NE flank started to record inflation; all this indicated the beginning of a new period of unrest. On August 14, five small phreatic explosions occurred, accompanied by large gas and ash emissions, ash falls were reported to the W of the volcano and to the S of Quito capital city. Three new episodes of ash and gas emissions occurred afterwards and towards the end of November 2015, the different monitoring parameters indicated a progressive reduction in the activity of the volcano. Since August 18 almost weekly overflights were made in order to conduct thermal (FLIR camera), visual and SO2 gas monitoring. Towards the end of August thermal measurements showed for the first time the presence of new thermal anomalies (13.5 to 16.3 °C) located in the crevices of the N glaciers, at the same time fumarolic gases were observed coming out from those fractures. On a flight made on September 3, the presence of water coming out from the basal fronts of the northern glaciers was clearly observed and the formation of narrow streams of water running downslope, while it was evident the appearance of countless new crevices in the majority of glacier ends, but also new cracks and rockslides on the upper flanks. All this led to the conclusion that an abnormal process was producing the melting of the glaciers around the volcano. Starting on September it was possible to observe the presence of small secondary lahars descending several streams and we estimated that many of them are due to increased glacier melting. Later

  9. Some notes on the behaviour of tropical glaciers

    Directory of Open Access Journals (Sweden)

    1995-01-01

    Full Text Available QUELQUES OBSERVATIONS SUR LE COMPORTEMENT DES GLACIERS TROPICAUX. Le fait qu’il soit possible sous les Tropiques de tirer des conclusions quasi immédiates sur le climat à partir des fluctuations des glaciers, en raison du caractère relativement homogène des masses d’air, rend les recherches glaciologiques dans ces régions particulièrement importantes. Une des caractéristiques du climat tropical est l’absence de variations thermiques saisonnières significatives. En tenant compte de ce fait, on évoque la relation climat-glacier sous deux de ses aspects : a la sensibilité de la ligne d’équilibre (ELA aux variations climatiques, et b la réponse correspondante des langues glaciaires. On discute de ces aspects par comparaison avec les conditions rencontrées dans les Alpes. La discussion est fondée sur un modèle de gradient vertical du bilan de masse (VGB. Comparée avec les glaciers des latitudes moyennes, la ELA réagit généralement de façon moins sensible, mais cependant plus fortement à un changement de température. Les langues, comme les petits glaciers réagissent de façon sensible à une ablation croissante. Les réponses à des influences dynamiques à long terme sont peu significatives. OBSERVACIONES SOBRE EL COMPORTAMIENTO DE LOS GLACIARES TROPICALES. El hecho de que se pueda llegar en los Trópicos a una conclusión casi inmediata sobre la evolución climática a partir de las fluctuaciones glaciares, debido al carácter relativamente homogéneo de las masas de aire, confiere a los estudios glaciológicos en esas regiones una grande importancia. Una de las características del clima tropical es la ausencia de variación térmica estacional significativa. Bajo este aspecto general, se trata de dos aspectos de la relación clima-glaciar: a la sensibilidad de la altitud de la línea de equilibrio glaciar (ELA a cambios climáticos y b la reacción correspondiente de las lenguas glaciares. Ambos aspectos son discutidos

  10. Methods for Automating Analysis of Glacier Morphology for Regional Modelling: Centerlines, Extensions, and Elevation Bands

    Science.gov (United States)

    Viger, R. J.; Van Beusekom, A. E.

    2016-12-01

    The treatment of glaciers in modeling requires information about their shape and extent. This presentation discusses new methods and their application in a new glacier-capable variant of the USGS PRMS model, a physically-based, spatially distributed daily time-step model designed to simulate the runoff and evolution of glaciers through time. In addition to developing parameters describing PRMS land surfaces (hydrologic response units, HRUs), several of the analyses and products are likely of interest to cryospheric science community in general. The first method is a (fully automated) variation of logic previously presented in the literature for definition of the glacier centerline. Given that the surface of a glacier might be convex, using traditional topographic analyses based on a DEM to trace a path down the glacier is not reliable. Instead a path is derived based on a cost function. Although only a single path is presented in our results, the method can be easily modified to delineate a branched network of centerlines for each glacier. The second method extends the glacier terminus downslope by an arbitrary distance, according to local surface topography. This product is can be used to explore possible, if unlikely, scenarios under which glacier area grows. More usefully, this method can be used to approximate glacier extents from previous years without needing historical imagery. The final method presents an approach for segmenting the glacier into altitude-based HRUs. Successful integration of this information with traditional approaches for discretizing the non-glacierized portions of a basin requires several additional steps. These include synthesizing the glacier centerline network with one developed with a traditional DEM analysis, ensuring that flow can be routed under and beyond glaciers to a basin outlet. Results are presented based on analysis of the Copper River Basin, Alaska.

  11. Measuring past glacier fluctuations from historic photographs geolocated using Structure from Motion

    Science.gov (United States)

    Vargo, L.; Anderson, B.; Horgan, H. J.; Mackintosh, A.; Lorrey, A.; Thornton, M.

    2017-12-01

    Quantifying glacier fluctuations is important for understanding how the cryosphere responds to climate variability and change. Photographs of past ice extents have become iconic images of climate change, but until now incorporating these images into quantitative estimates of glacier change has been problematic. We present a new method to quantitatively measure past glacier fluctuations from historic images. The method uses a large set of modern geolocated photographs and Structure from Motion (SfM) to calculate the camera parameters for the historic images, including the location from which they were taken. We initially apply this method to a small maritime New Zealand glacier (Brewster Glacier, 44°S, 2 km2), and quantify annual equilibrium line altitudes (ELAs) and length changes from historic oblique aerial photographs (1981 - 2017). Results show that Brewster has retreated 364 ± 12 m since 1981 and, using independent field measurements of terminus positions (2005 - 2014), we show that this SfM-derived length record accurately captures glacier change. We calculate the uncertainties associated with this method using known coordinates of bedrock features surrounding the glacier. Mean uncertainties in the ELA and length records are 7 m and 11 m, respectively. In addition to Brewster, 49 other New Zealand glaciers have been monitored by aerial photographs since 1978. However, the length records for these glaciers only include years of relative advance or retreat, and no length changes have been quantified. We will ultimately apply this method to all 50 glaciers, expanding the database of New Zealand glacier fluctuations that until now included only a few glaciers. This method can be further applied to any glacier with historic images, and can be used to measure past changes in glacier width, area, and surface elevation in addition to ELA and length.

  12. Nuclear regulation - the Canadian approach

    International Nuclear Information System (INIS)

    Jennekens, J.

    1981-09-01

    Although the Atomic Energy Control Board was established 35 years ago the basic philosophy of nuclear regulation in Canada and the underlying principles of the regulatory process remain essentially unchanged. This paper outlines the Canadian approach to nuclear regulation and explains in practical terms how the principles of regulation are applied. (author)

  13. Canadian Government Electronic Information Policy.

    Science.gov (United States)

    Nilsen, Kirsti

    1993-01-01

    Examines development and evolution of Canadian government information policy in response to issues of preservation of data, information industry involvement in government data development and marketing, role of Crown copyright, and public access to government information in electronic formats. Six key information policy instruments are also…

  14. Engendering migrant health: Canadian perspectives

    National Research Council Canada - National Science Library

    Spitzer, Denise L

    2011-01-01

    .... Focusing on the context of Canadian policy and society, the contributors illuminate migrants' testimonies of struggle, resistance, and solidarity as they negotiate a place for themselves in a new country. Topics range from the difficulties of Francophone refugees and the changing roles of fathers, to the experiences of queer newcomers and the importance of social unity to communal and individual health."--pub. desc.

  15. Canadian Postcolonialism: Recovering British Roots

    Science.gov (United States)

    Doughty, Howard A.

    2005-01-01

    The field of Postcolonial Studies is one of the academic fashions that has arisen in an attempt to amend or replace radical theories of social power since the alleged discrediting of Marxism. The Canadian case is more ambiguous. Postcolonialism, already an essentially contested concept, is especially conflicted where Canada is concerned. Canada…

  16. Earth's Climate History from Glaciers and Ice Cores

    Science.gov (United States)

    Thompson, Lonnie

    2013-03-01

    Glaciers serve both as recorders and early indicators of climate change. Over the past 35 years our research team has recovered climatic and environmental histories from ice cores drilled in both Polar Regions and from low to mid-latitude, high-elevation ice fields. Those ice core -derived proxy records extending back 25,000 years have made it possible to compare glacial stage conditions in the Tropics with those in the Polar Regions. High-resolution records of δ18O (in part a temperature proxy) demonstrate that the current warming at high elevations in the mid- to lower latitudes is unprecedented for the last two millennia, although at many sites the early Holocene was warmer than today. Remarkable similarities between changes in the highland and coastal cultures of Peru and regional climate variability, especially precipitation, imply a strong connection between prehistoric human activities and regional climate. Ice cores retrieved from shrinking glaciers around the world confirm their continuous existence for periods ranging from hundreds to thousands of years, suggesting that current climatological conditions in those regions today are different from those under which these ice fields originated and have been sustained. The ongoing widespread melting of high-elevation glaciers and ice caps, particularly in low to middle latitudes, provides strong evidence that a large-scale, pervasive and, in some cases, rapid change in Earth's climate system is underway. Observations of glacier shrinkage during the 20th and 21st century girdle the globe from the South American Andes, the Himalayas, Kilimanjaro (Tanzania, Africa) and glaciers near Puncak Jaya, Indonesia (New Guinea). The history and fate of these ice caps, told through the adventure, beauty and the scientific evidence from some of world's most remote mountain tops, provide a global perspective for contemporary climate. NSF Paleoclimate Program

  17. Spatial and temporal variations in glacier hydrology on Storglaciaeren, Sweden

    International Nuclear Information System (INIS)

    Jansson, Peter; Naeslund, Jens-Ove

    2009-06-01

    The aim of the current research project was to provide a framework of real conditions within which to interpret theory and extrapolate likely conditions beneath a future ice sheet over Fennoscandia. The purpose of this report is to summarize the experimental work on glacier hydrology and basal hydraulic conditions performed on Storglaciaeren, northern Sweden, during the years 1990-2006. Surface fed subglacial hydrological systems are extremely dynamic because the input rates of rain and temperature-controlled surface melt fluctuate, and the geometry of flow paths is constantly changing due to ice deformation which tends to open and close the flow paths. The hydrological system of a glacier is quite unusual because since liquid water flows through conduits made of its solid phase (ice). Understanding the expected dynamic range of a glacier's hydrological system is best studied by in situ measurements. The processes studied on Storglaciaeren can be expected to apply to ice sheet scale, albeit on different spatial scales. Since Storglaciaeren is a polythermal glacier with a large fraction of ice below freezing and at the melting point and with a surface-fed hydrological system of conduits and tunnels, results apply to the lower elevation regions where the surface is composed of ice (ablation zone) rather than composed of snow (accumulation zone) found at higher elevations of the glaciers and ice sheets, Therefore, our results apply to the ablation zone of the past Fennoscandian Ice Sheet. In this report we discuss the measurements made to assess the subglacial conditions that provide a potential analogue for conditions under the Fennoscandian Ice Sheet. For this purpose field work was performed on from 2003 to 2006 yielding subglacial water pressure measurements. We have included a large quantity of unpublished data from Storglaciaeren from different research projects conducted since 1990. Together these data provide a picture of the temporal and spatial water

  18. Spatial and temporal variations in glacier hydrology on Storglaciaeren, Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Peter (Dept. of Physical Geography and Quaternary Geology, Stockholm Univ., Stockholm (Sweden)); Naeslund, Jens-Ove (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden))

    2009-06-15

    The aim of the current research project was to provide a framework of real conditions within which to interpret theory and extrapolate likely conditions beneath a future ice sheet over Fennoscandia. The purpose of this report is to summarize the experimental work on glacier hydrology and basal hydraulic conditions performed on Storglaciaeren, northern Sweden, during the years 1990-2006. Surface fed subglacial hydrological systems are extremely dynamic because the input rates of rain and temperature-controlled surface melt fluctuate, and the geometry of flow paths is constantly changing due to ice deformation which tends to open and close the flow paths. The hydrological system of a glacier is quite unusual because since liquid water flows through conduits made of its solid phase (ice). Understanding the expected dynamic range of a glacier's hydrological system is best studied by in situ measurements. The processes studied on Storglaciaeren can be expected to apply to ice sheet scale, albeit on different spatial scales. Since Storglaciaeren is a polythermal glacier with a large fraction of ice below freezing and at the melting point and with a surface-fed hydrological system of conduits and tunnels, results apply to the lower elevation regions where the surface is composed of ice (ablation zone) rather than composed of snow (accumulation zone) found at higher elevations of the glaciers and ice sheets, Therefore, our results apply to the ablation zone of the past Fennoscandian Ice Sheet. In this report we discuss the measurements made to assess the subglacial conditions that provide a potential analogue for conditions under the Fennoscandian Ice Sheet. For this purpose field work was performed on from 2003 to 2006 yielding subglacial water pressure measurements. We have included a large quantity of unpublished data from Storglaciaeren from different research projects conducted since 1990. Together these data provide a picture of the temporal and spatial water

  19. Modeled and measured glacier change and related glaciological, hydrological, and meteorological conditions at South Cascade Glacier, Washington, balance and water years 2006 and 2007

    Science.gov (United States)

    Bidlake, William R.; Josberger, Edward G.; Savoca, Mark E.

    2010-01-01

    Winter snow accumulation and summer snow and ice ablation were measured at South Cascade Glacier, Washington, to estimate glacier mass balance quantities for balance years 2006 and 2007. Mass balances were computed with assistance from a new model that was based on the works of other glacier researchers. The model, which was developed for mass balance practitioners, coupled selected meteorological and glaciological data to systematically estimate daily mass balance at selected glacier sites. The North Cascade Range in the vicinity of South Cascade Glacier accumulated approximately average to above average winter snow packs during 2006 and 2007. Correspondingly, the balance years 2006 and 2007 maximum winter snow mass balances of South Cascade Glacier, 2.61 and 3.41 meters water equivalent, respectively, were approximately equal to or more positive (larger) than the average of such balances since 1959. The 2006 glacier summer balance, -4.20 meters water equivalent, was among the four most negative since 1959. The 2007 glacier summer balance, -3.63 meters water equivalent, was among the 14 most negative since 1959. The glacier continued to lose mass during 2006 and 2007, as it commonly has since 1953, but the loss was much smaller during 2007 than during 2006. The 2006 glacier net balance, -1.59 meters water equivalent, was 1.02 meters water equivalent more negative (smaller) than the average during 1953-2005. The 2007 glacier net balance, -0.22 meters water equivalent, was 0.37 meters water equivalent less negative (larger) than the average during 1953-2006. The 2006 accumulation area ratio was less than 0.10, owing to isolated patches of accumulated snow that endured the 2006 summer season. The 2006 equilibrium line altitude was higher than the glacier. The 2007 accumulation area ratio and equilibrium line altitude were 0.60 and 1,880 meters, respectively. Accompanying the glacier mass losses were retreat of the terminus and reduction of total glacier area. The

  20. The effect of a small creek valley on drainage flows in the Rocky Flats region

    International Nuclear Information System (INIS)

    Porch, W.

    1996-01-01

    Regional scale circulation and mountain-plain interactions and effects on boundary layer development are important for understanding the fate of an atmospheric release from Rocky Flats, Colorado. Numerical modeling of Front Range topographic effects near Rocky Flats have shown that though the Front Range dominates large scale flow features, small-scale terrain features near Rocky Flats are important to local transport during nighttime drainage flow conditions. Rocky Flats has been the focus of interest for the Department of Energy's Atmospheric Studies in Complex Terrain (ASCOT) program

  1. The Neoglacial landscape and human history of Glacier Bay, Glacier Bay National Park and Preserve, southeast Alaska, USA

    Science.gov (United States)

    Connor, C.; Streveler, G.; Post, A.; Monteith, D.; Howell, W.

    2009-01-01

    The Neoglacial landscape of the Huna Tlingit homeland in Glacier Bay is recreated through new interpretations of the lower Bay's fjordal geomorphology, late Quaternary geology and its ethnographic landscape. Geological interpretation is enhanced by 38 radiocarbon dates compiled from published and unpublished sources, as well as 15 newly dated samples. Neoglacial changes in ice positions, outwash and lake extents are reconstructed for c. 5500?????"200 cal. yr ago, and portrayed as a set of three landscapes at 1600?????"1000, 500?????"300 and 300?????"200 cal. yr ago. This history reveals episodic ice advance towards the Bay mouth, transforming it from a fjordal seascape into a terrestrial environment dominated by glacier outwash sediments and ice-marginal lake features. This extensive outwash plain was building in lower Glacier Bay by at least 1600 cal. yr ago, and had filled the lower bay by 500 cal. yr ago. The geologic landscape evokes the human-described landscape found in the ethnographic literature. Neoglacial climate and landscape dynamism created difficult but endurable environmental conditions for the Huna Tlingit people living there. Choosing to cope with environmental hardship was perhaps preferable to the more severely deteriorating conditions outside of the Bay as well as conflicts with competing groups. The central portion of the outwash plain persisted until it was overridden by ice moving into Icy Strait between AD 1724?????"1794. This final ice advance was very abrupt after a prolonged still-stand, evicting the Huna Tlingit from their Glacier Bay homeland. ?? 2009 SAGE Publications.

  2. Liquid fuels from Canadian coals

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, G. W.

    1979-06-15

    In Canadian energy planning, the central issue of security of supply must be addressed by developing flexible energy systems that make the best possible use of available resources. For liquid fuel production, oil sands and heavy oil currently appear more attractive than coal or biomass as alternatives to conventional crude oil, but the magnitude of their economic advantage is uncertain. The existence of large resources of oil sands, heavy oils, natural gas and low-sulfur coals in Western Canada creates a unique opportunity for Canadians to optimize the yield from these resources and develop new technology. Many variations on the three basic liquefaction routes - hydroliquefaction, pyrolysis and synthesis - are under investigation around the world, and the technology is advancing rapidly. Each process has merit under certain circumstances. Surface-mineable subbituminous and lignite coals of Alberta and Saskatchewan appear to offer the best combination of favorable properties, deposit size and mining cost, but other deposits in Alberta, Nova Scotia and British Columbia should not be ruled out. The research effort in Canada is small by world standards, but it is unlikely that technology could be imported that is ideally suited to Canadian conditions. Importing technology is undesirable: innovation or process modification to suit Canadian coals and markets is preferred; coprocessing of coal liquids with bitumen or heavy oils would be a uniquely Canadian, exportable technology. The cost of synthetic crude from coal in Canada is uncertain, estimates ranging from $113 to $220/m/sup 3/ ($18 to $35/bbl). Existing economic evaluations vary widely depending on assumptions, and can be misleading. Product quality is an important consideration.

  3. Bacteria at glacier surfaces: microbial community structures in debris covered glaciers and cryoconites in the Italian Alps

    Science.gov (United States)

    Azzoni, Roberto; Franzetti, Andrea; Ambrosini, Roberto; D'Agata, Carlo; Senese, Antonella; Minora, Umberto; Tagliaferri, Ilario; Diolaiuti, Guglielmina

    2014-05-01

    Supraglacial debris has an important role in the glacier energy budget and has strong influence on the glacial ecosystem. Sediment derives generally from rock inputs from nesting rockwalls and are abundant and continuous at the surface of debris-covered glaciers (i.e. DCGs; glaciers where the ablation area is mainly covered by rock debris) and sparse and fine on debris-free glaciers (DFGs). Recently, evidence for significant tongue darkening on retreating debris-free glaciers has been drawing increasing attention. Fine particles, the cryoconite, are locally abundant and may form cryoconite holes that are water-filled depressions on the surface of DFGs that form when a thin layer of cryoconite is heated by the sun and melts the underlying ice. There is increasing evidence that cryoconite holes also host highly diverse microbial communities and can significantly contribute to global carbon cycle. However, there is almost no study on microbial communities of the debris cover of DCGs and there is a lack of data from the temporal evolution of the microbial communities in the cryoconites. To fill these gaps in our knowledge we characterized the supraglacial debris of two Italian DCGs and we investigated the temporal evolution of microbial communities on cryoconite holes in DFG. We used the Illumina technology to analyse the V5 and V6 hypervariable regions of the bacterial 16S rRNA gene amplified from samples collected distances from the terminus of two DCGs (Miage and Belvedere Glaciers - Western Italian Alps). Heterotrophic taxa dominated bacterial communities, whose structure changed during downwards debris transport. Organic carbon of these recently exposed substrates therefore is probably provided more by allochthonous deposition of organic matter than by primary production by autotrophic organisms. We used ARISA fingerprinting and quantitative PCR to describe the structure and the evolution of the microbial communities and to estimate the number of the total

  4. Hydrology, microbiology and carbon cycling at a high Arctic polythermal glacier, (John Evans Glacier, Ellesmere Island, Canada)

    Science.gov (United States)

    Skidmore, Mark Leslie

    Analysis of the hydrology, hydrochemistry and microbiology at polythermal John Evans Glacier and geochemical and isotopic data from Haut Glacier d'Arolla demonstrates that certain subglacial chemical weathering processes are microbially mediated. Subglacial drainage is likely an annual occurrence beneath John Evans Glacier and solute rich subglacial waters indicate over winter storage at the glacier bed. Subglacial microbial populations are also present, and are viable under simulated near in situ conditions at 0.3°C. This suggests that temperate subglacial environments at a polythermal glacier, which are isolated by cold ice above and around them, provide a viable habitat for life where basal water and organic carbon are present throughout the year. Thus, a subglacial microbial ecosystem based upon legacy carbon, (from old soils or surface inputs) rather than primary production may exist, where redox processes are a key component, and seasonal anoxia may occur. The existence of anoxic environments is supported by the presence of strictly anaerobic bacteria (sulphate reducing bacteria and methanogens) in the basal sediments---which are viable in culture at 4°C---and also argues that these bacteria are not washed in with oxygenated surface meltwaters, but are present in the subglacial environment. During the summer meltseason there is a large input of surficial waters to the subglacial system and water residence times are drastically reduced. Hence, kinetic weathering processes dominate, resulting in light delta 13C-DIC (dissolved inorganic carbon) in glacial runoff, as verified by experimental work on CaCO3 and John Evans Glacier sediments. The experiments demonstrate kinetic bedrock fractionation (KBF) during carbonate hydrolysis and that kinetic fractionation of CO2 (KFC) is proportional to the rate of CO2 draw down during the carbonation of carbonates. This results in significantly depleted delta13C-DIC values (≤-16 ‰) relative to the bedrock carbonate

  5. Hydrologic controls on radiogenic Sr in meltwater from an alpine glacier system: Athabasca Glacier, Canada

    International Nuclear Information System (INIS)

    Arendt, C.A.; Stevenson, E.I.; Aciego, S.M.

    2016-01-01

    Filtered subglacial meltwater samples were collected daily during the onset of melt (May) and peak melt (July) over the 2011 melt season at the Athabasca Glacier (Alberta, Canada) and analyzed for strontium-87/strontium-86 ("8"7Sr/"8"6Sr) isotopic composition to infer the evolution of subglacial weathering processes. Both the underlying bedrock composition and subglacial water–rock interaction time are the primary influences on meltwater "8"7Sr/"8"6Sr. The Athabasca Glacier is situated atop Middle Cambrian carbonate bedrock that also contains silicate minerals. The length of time that subglacial meltwater interacts with the underlying bedrock and substrate is a predominant determining factor in solute concentration. Over the course of the melt season, increasing trends in Ca/K and Ca/Mg correspond to overall decreasing trends in "8"7Sr/"8"6Sr, which indicate a shift in weathering processes from the presence of silicate weathering to primarily carbonate weathering. Early in the melt season, rates of carbonate dissolution slow as meltwater approaches saturation with respect to calcite and dolomite, corresponding to an increase in silicate weathering that includes Sr-rich silicate minerals, and an increase in meltwater "8"7Sr/"8"6Sr. However, carbonate minerals are preferentially weathered in unsaturated waters. During the warmest part of a melt season the discharged meltwater is under saturated, causing an increase in carbonate weathering and a decrease in the radiogenic Sr signal. Likewise, larger fraction contributions of meltwater from glacial ice corresponds to lower "8"7Sr/"8"6Sr values, as the meltwater has lower water–rock interaction times in the subglacial system. These results indicate that although weathering of Sr-containing silicate minerals occurs in carbonate dominated glaciated terrains, the continual contribution of new meltwater permits the carbonate weathering signal to dominate. - Highlights: • Glacial meltwater "8"7Sr/"8"6Sr used to

  6. Post-Little Landscape and Glacier Change in Glacier Bay National Park: Documenting More than a Century of Variability with Repeat Photography

    Science.gov (United States)

    Molnia, B. F.; Karpilo, R. D.; Pranger, H. S.

    2004-12-01

    Historical photographs, many dating from the late-19th century are being used to document landscape and glacier change in the Glacier Bay area. More than 350 pre-1980 photographs that show the Glacier Bay landscape and glacier termini positions have been acquired by the authors. Beginning in 2003, approximately 150 of the sites from which historical photographs had been made were revisited. At each site, elevation and latitude and longitude were recorded using WAAS-enabled GPS. Compass bearings to photographic targets were also determined. Finally, using the historical photographs as a composition guide, new photographs were exposed using digital imaging and film cameras. In the laboratory, 21st century images and photographs were compared with corresponding historical photographs to determine, and to better understand rates, timing, and mechanics of Glacier Bay landscape evolution, as well as to clarify the response of specific glaciers to changing climate and environment. The comparisons clearly document rapid vegetative succession throughout the bay; continued retreat of larger glaciers in the East Arm of the bay; a complex pattern of readvance and retreat of the larger glaciers in the West Arm of the bay, coupled with short-term fluctuations of its smaller glaciers; transitions from tidewater termini to stagnant, debris-covered termini; fiord sedimentation and erosion; development of outwash and talus features; and many other dramatic changes. As might be expected, 100-year-plus photo comparisons show significant changes throughout the Glacier Bay landscape, especially at the southern ends of East and West Arms. Surprisingly, recent changes, occurring since the late-1970s were equally dramatic, especially documenting the rapid thinning and retreat of glaciers in upper Muir Inlet.

  7. Do morphometric parameters and geological conditions determine chemistry of glacier surface ice? Spatial distribution of contaminants present in the surface ice of Spitsbergen glaciers (European Arctic).

    Science.gov (United States)

    Lehmann, Sara; Gajek, Grzegorz; Chmiel, Stanisław; Polkowska, Żaneta

    2016-12-01

    The chemism of the glaciers is strongly determined by long-distance transport of chemical substances and their wet and dry deposition on the glacier surface. This paper concerns spatial distribution of metals, ions, and dissolved organic carbon, as well as the differentiation of physicochemical parameters (pH, electrical conductivity) determined in ice surface samples collected from four Arctic glaciers during the summer season in 2012. The studied glaciers represent three different morphological types: ground based (Blomlibreen and Scottbreen), tidewater which evolved to ground based (Renardbreen), and typical tidewater glacier (Recherchebreen). All of the glaciers are functioning as a glacial system and hence are subject to the same physical processes (melting, freezing) and the process of ice flowing resulting from the cross-impact force of gravity and topographic conditions. According to this hypothesis, the article discusses the correlation between morphometric parameters, changes in mass balance, geological characteristics of the glaciers and the spatial distribution of analytes on the surface of ice. A strong correlation (r = 0.63) is recorded between the aspect of glaciers and values of pH and ions, whereas dissolved organic carbon (DOC) depends on the minimum elevation of glaciers (r = 0.55) and most probably also on the development of the accumulation area. The obtained results suggest that although certain morphometric parameters largely determine the spatial distribution of analytes, also the geology of the bed of glaciers strongly affects the chemism of the surface ice of glaciers in the phase of strong recession.

  8. Effect of Topography on Subglacial Discharge and Submarine Melting During Tidewater Glacier Retreat

    Science.gov (United States)

    Amundson, J. M.; Carroll, D.

    2018-01-01

    To first order, subglacial discharge depends on climate, which determines precipitation fluxes and glacier mass balance, and the rate of glacier volume change. For tidewater glaciers, large and rapid changes in glacier volume can occur independent of climate change due to strong glacier dynamic feedbacks. Using an idealized tidewater glacier model, we show that these feedbacks produce secular variations in subglacial discharge that are influenced by subglacial topography. Retreat along retrograde bed slopes (into deep water) results in rapid surface lowering and coincident increases in subglacial discharge. Consequently, submarine melting of glacier termini, which depends on subglacial discharge and ocean thermal forcing, also increases during retreat into deep water. Both subglacial discharge and submarine melting subsequently decrease as glacier termini retreat out of deep water and approach new steady state equilibria. In our simulations, subglacial discharge reached peaks that were 6-17% higher than preretreat values, with the highest values occurring during retreat from narrow sills, and submarine melting increased by 14% for unstratified fjords and 51% for highly stratified fjords. Our results therefore indicate that submarine melting acts in concert with iceberg calving to cause tidewater glacier termini to be unstable on retrograde beds. The full impact of submarine melting on tidewater glacier stability remains uncertain, however, due to poor understanding of the coupling between submarine melting and iceberg calving.

  9. Estimation of Shie Glacier Surface Movement Using Offset Tracking Technique with Cosmo-Skymed Images

    Science.gov (United States)

    Wang, Q.; Zhou, W.; Fan, J.; Yuan, W.; Li, H.; Sousa, J. J.; Guo, Z.

    2017-09-01

    Movement is one of the most important characteristics of glaciers which can cause serious natural disasters. For this reason, monitoring this massive blocks is a crucial task. Synthetic Aperture Radar (SAR) can operate all day in any weather conditions and the images acquired by SAR contain intensity and phase information, which are irreplaceable advantages in monitoring the surface movement of glaciers. Moreover, a variety of techniques like DInSAR and offset tracking, based on the information of SAR images, could be applied to measure the movement. Sangwang lake, a glacial lake in the Himalayas, has great potentially danger of outburst. Shie glacier is situated at the upstream of the Sangwang lake. Hence, it is significant to monitor Shie glacier surface movement to assess the risk of outburst. In this paper, 6 high resolution COSMO-SkyMed images spanning from August to December, 2016 are applied with offset tracking technique to estimate the surface movement of Shie glacier. The maximum velocity of Shie glacier surface movement is 51 cm/d, which was observed at the end of glacier tongue, and the velocity is correlated with the change of elevation. Moreover, the glacier surface movement in summer is faster than in winter and the velocity decreases as the local temperature decreases. Based on the above conclusions, the glacier may break off at the end of tongue in the near future. The movement results extracted in this paper also illustrate the advantages of high resolution SAR images in monitoring the surface movement of small glaciers.

  10. Measurement of glacier velocity at Pik Lenin, Tajikistan, by feature tracking

    Science.gov (United States)

    Kumari, S.; Ghosh, S. K.; Buchroithner, M. F.

    2014-11-01

    Glaciers, especially in mountain area are sensitive indicators of climate fluctuations and also contribute to present rates of sea level rise. In Central Asia, these glaciers are the primary resource for fresh water. Understanding the seasonal behavior of these glaciers would help to make efficient use of the available water reservoir. Different methods have been employed to study glacier displacements in past. The conventional survey techniques are very cost-intensive and highly depend on accessibility to high mountain glaciers also directs us to look for new ways to study these areas. Here remote sensing comes in handy with freely available data and a good coverage with high spatial and temporal resolution. Optical satellite imagery, available free can be effectively used for research purpose. The glacier in this region fed lake Karakul (380 km2), the largest Lake in Tajikistan. The objective is to study the displacement tendency of the Glacier in Pik Lenin area using Landsat 7 dataset. Normalized cross correlation algorithm has been implemented via CIAS to estimate the motion of glacier surface. A number of combination of reference block and search area size were tested for 30 m resolution dataset. As a result the specifications: reference block size of 15 pixels and search area size of 10 pixels was found out as the best set of parameters and considered for further processing. The study derives a reliable set of data depicting the velocities in the glacier which after post processing shows peak velocity of 121 m/y of the glacier.

  11. Glacier Monitoring and Capacity Building: Important Ingredients for Sustainable Mountain Development

    Directory of Open Access Journals (Sweden)

    Samuel U. Nussbaumer

    2017-02-01

    Full Text Available Glacier observation data from major mountain regions of the world are key to improving our understanding of glacier changes: they deliver fundamental baseline information for climatological, hydrological, and hazard assessments. In many mountain ecosystems, as well as in the adjacent lowlands, glaciers play a crucial role in freshwater provision and regulation. This article first presents the state of the art on glacier monitoring and related strategies within the framework of the Global Terrestrial Network for Glaciers (GTN-G. Both in situ measurements of changes in glacier mass, volume, and length as well as remotely sensed data on glacier extents and changes over entire mountain ranges provide clear indications of climate change. Based on experiences from capacity-building activities undertaken in the Tropical Andes and Central Asia over the past years, we also review the state of the art on institutional capacity in these regions and make further recommendations for sustainable mountain development. The examples from Peru, Ecuador, Colombia, and Kyrgyzstan demonstrate that a sound understanding of measurement techniques and of the purpose of measurements is necessary for successful glacier monitoring. In addition, establishing durable institutions, capacity-building programs, and related funding is necessary to ensure that glacier monitoring is sustainable and maintained in the long term. Therefore, strengthening regional cooperation, collaborating with local scientists and institutions, and enhancing knowledge sharing and dialogue are envisaged within the GTN-G. Finally, glacier monitoring enhances the resilience of the populations that depend on water resources from glacierized mountains or that are affected by hazards related to glacier changes. We therefore suggest that glacier monitoring be included in the development of sustainable adaptation strategies in regions with glaciated mountains.

  12. The retreat of the world's mountain glaciers during recent decades; Le retrait des glaciers de montagne dans le monde au cours des dernieres decennies

    Energy Technology Data Exchange (ETDEWEB)

    Francou, B. [Institut de Recherche pour le Developpement (IRD), Mission de Quito, Equateur - LTHE, 38 - Grenoble (France); Vincent, Ch. [Centre National de la Recherche Scientifique (CNRS), UJF, LGGE, 38 - Grenoble (France)

    2009-08-15

    Glaciers have become essential tools for measuring changes in the global environment. Here, we analyze glacier evolution during the last few decades and we wonder whether the observed retreat remains in the range of glacier fluctuations since the mid-Holocene. The main fluctuations experienced by glaciers during the last millenniums, and particularly during the Little Ice Age (-1300 A.D. to {approx}1860 A.D.), are presented succinctly. The recent 1960-2005 period, well documented both by ground and remote sensing observations, shows important disparities between different massifs concerning the timing and the magnitude of glacier fluctuations, which depend on regional climatic conditions. The links between glacier mass balance evolution and climate is clear when approached from an energy balance but the variables commonly considered are only temperature and precipitation. The strong correlation existing between these variables and the mass balance evolution makes it possible to simulate glaciers in the future in function of distinct climatic scenarios. Modeling glacier retreat for the 21. century is an important goal because it will allow the impacts on water resource and sea level to be assessed. (authors)

  13. Bed-Deformation Experiments Beneath a Temperate Glacier

    Science.gov (United States)

    Iverson, N. R.; Hooyer, T. S.; Fischer, U. H.; Cohen, D.; Jackson, M.; Moore, P. L.; Lappegard, G.; Kohler, J.

    2002-12-01

    Fast flow of glaciers and genesis of glacial landforms are commonly attributed to shear deformation of subglacial sediment. Although models of this process abound, data gathered subglacially on the kinematics and mechanics of such deformation are difficult to interpret. Major difficulties stem from the necessity of either measuring deformation near glacier margins, where conditions may be abnormal, or at the bottoms of boreholes, where the scope of instrumentation is limited, drilling disturbs sediment, and local boundary conditions are poorly known. A different approach is possible at the Svartisen Subglacial Laboratory, where tunnels melted in the ice provide temporary human access to the bed of Engabreen, a temperate outlet glacier of the Svartisen Ice Cap in Norway. A trough (2 m x 1.5 m x 0.5 m deep) was blasted in the rock bed, where the glacier is 220 m thick and sliding at 0.1-0.2 m/d. During two spring field seasons, this trough was filled with 2.5 tons of simulated till. Instruments in the till recorded shear (tiltmeters), volume change, total normal stress, and pore-water pressure as ice moved across the till surface. Pore pressure was brought to near the total normal stress by feeding water to the base of the till with a high-pressure pump, operated in a rock tunnel 4 m below the bed surface. Results illustrate some fundamental aspects of bed deformation. Permanent shear deformation requires low effective normal stress and hence high pore-water pressure, owing to the frictional nature of till. Shear strain generally increases upward in the bed toward the glacier sole, consistent with previous measurements beneath thinner ice at glacier margins. At low effective normal stresses, ice sometimes decouples from underlying till. Overall, bed deformation accounts for 10-35 % of basal motion, although this range excludes shear in the uppermost 0.05 m of till where shear was not measured. Pump tests with durations ranging from seconds to hours highlight the need

  14. Cascading effects of ocean acidification in a rocky subtidal community.

    Directory of Open Access Journals (Sweden)

    Valentina Asnaghi

    Full Text Available Temperate marine rocky habitats may be alternatively characterized by well vegetated macroalgal assemblages or barren grounds, as a consequence of direct and indirect human impacts (e.g. overfishing and grazing pressure by herbivorous organisms. In future scenarios of ocean acidification, calcifying organisms are expected to be less competitive: among these two key elements of the rocky subtidal food web, coralline algae and sea urchins. In order to highlight how the effects of increased pCO2 on individual calcifying species will be exacerbated by interactions with other trophic levels, we performed an experiment simultaneously testing ocean acidification effects on primary producers (calcifying and non-calcifying algae and their grazers (sea urchins. Artificial communities, composed by juveniles of the sea urchin Paracentrotus lividus and calcifying (Corallina elongata and non-calcifying (Cystoseira amentacea var stricta, Dictyota dichotoma macroalgae, were subjected to pCO2 levels of 390, 550, 750 and 1000 µatm in the laboratory. Our study highlighted a direct pCO2 effect on coralline algae and on sea urchin defense from predation (test robustness. There was no direct effect on the non-calcifying macroalgae. More interestingly, we highlighted diet-mediated effects on test robustness and on the Aristotle's lantern size. In a future scenario of ocean acidification a decrease of sea urchins' density is expected, due to lower defense from predation, as a direct consequence of pH decrease, and to a reduced availability of calcifying macroalgae, important component of urchins' diet. The effects of ocean acidification may therefore be contrasting on well vegetated macroalgal assemblages and barren grounds: in the absence of other human impacts, a decrease of biodiversity can be predicted in vegetated macroalgal assemblages, whereas a lower density of sea urchin could help the recovery of shallow subtidal rocky areas affected by overfishing from

  15. Cascading effects of ocean acidification in a rocky subtidal community.

    Science.gov (United States)

    Asnaghi, Valentina; Chiantore, Mariachiara; Mangialajo, Luisa; Gazeau, Frédéric; Francour, Patrice; Alliouane, Samir; Gattuso, Jean-Pierre

    2013-01-01

    Temperate marine rocky habitats may be alternatively characterized by well vegetated macroalgal assemblages or barren grounds, as a consequence of direct and indirect human impacts (e.g. overfishing) and grazing pressure by herbivorous organisms. In future scenarios of ocean acidification, calcifying organisms are expected to be less competitive: among these two key elements of the rocky subtidal food web, coralline algae and sea urchins. In order to highlight how the effects of increased pCO2 on individual calcifying species will be exacerbated by interactions with other trophic levels, we performed an experiment simultaneously testing ocean acidification effects on primary producers (calcifying and non-calcifying algae) and their grazers (sea urchins). Artificial communities, composed by juveniles of the sea urchin Paracentrotus lividus and calcifying (Corallina elongata) and non-calcifying (Cystoseira amentacea var stricta, Dictyota dichotoma) macroalgae, were subjected to pCO2 levels of 390, 550, 750 and 1000 µatm in the laboratory. Our study highlighted a direct pCO2 effect on coralline algae and on sea urchin defense from predation (test robustness). There was no direct effect on the non-calcifying macroalgae. More interestingly, we highlighted diet-mediated effects on test robustness and on the Aristotle's lantern size. In a future scenario of ocean acidification a decrease of sea urchins' density is expected, due to lower defense from predation, as a direct consequence of pH decrease, and to a reduced availability of calcifying macroalgae, important component of urchins' diet. The effects of ocean acidification may therefore be contrasting on well vegetated macroalgal assemblages and barren grounds: in the absence of other human impacts, a decrease of biodiversity can be predicted in vegetated macroalgal assemblages, whereas a lower density of sea urchin could help the recovery of shallow subtidal rocky areas affected by overfishing from barren grounds to

  16. Rocky Flats Neutron Detector Testing at Valduc, France

    International Nuclear Information System (INIS)

    Kim, S.S.; Dulik, G.M.

    2011-01-01

    Recent program requirements of the US Department of Energy/NNSA have led to a need for a criticality accident alarm system to be installed at a newly activated facility. The Criticality Safety Group of the Lawrence Livermore National Laboratory (LLNL) was able to recover and store for possible future use approximately 200 neutron criticality detectors and 20 master alarm panels from the former Rocky Flats Plant in Golden, Colorado when the plant was closed. The Criticality Safety Group participated in a facility analysis and evaluation, the engineering design and review process, as well as the refurbishment, testing, and recalibration of the Rocky Flats criticality alarm system equipment to be used in the new facility. In order to demonstrate the functionality and survivability of the neutron detectors to the effects of an actual criticality accident, neutron detector testing was performed at the French CEA Valduc SILENE reactor from October 7 to October 19, 2010. The neutron detectors were exposed to three criticality events or pulses generated by the SILENE reactor. The first excursion was performed with a bare or unshielded reactor, and the second excursion was made with a lead shielded/reflected reactor, and the third excursion with a polyethylene reflected core. These tests of the Rocky Flats neutron detectors were performed as a part of the 2010 Criticality Accident Alarm System Benchmark Measurements at the SILENE Reactor. The principal investigators for this series of experiments were Thomas M. Miller and John C. Wagner of the Oak Ridge National Laboratory, with Nicolas Authier and Nathalie Baclet of CEA Valduc. Several other organizations were also represented, including the Y-12 National Security Complex, Lawrence Livermore National Laboratory, Los Alamos National Laboratory, CEA Saclay, and Babcock International Group.

  17. Dry calving processes at the ice cliff of an antarctic local glacier: the study case of Strandline Glacier (Northern Victoria Land, Antarctica)

    Science.gov (United States)

    Smiraglia, C.; Motta, M.; Vassena, G.; Diolaiuti, G.

    2003-04-01

    In Antartic coastal area, where the ice sheet and the large outlet glaciers do not reach the sea and where some rugged mountain chains are often present, many small glaciers can be found. They are the so called local or alpine type glaciers, which have their terminus ground-based such as the real alpine glaciers and rarely reach the main valley floors. They are practically isolated and independent from the supply flowing down from the plateau and their mass balance is mainly controlled by sublimation and aeolic erosion and accumulation. The glaciers closer to the coast are submitted to the melting as well, and when the terminus is cliff-shaped they are also affected by dry calving. The most known and studied Antarctic local glaciers are placed in the Dry Valleys region (Chinn, 1985), but this kind of glaciers is also diffused all along the Northern Victoria Land coastal region (Chinn and others, 1989). Since the first Italian Antarctic expedition (1985), many studies have been carried out on this type of glaciers, which can be usefull for detailed mass balance evaluations and for obtaining information about the effects of the present climatic dynamics on the Antarctic coastal environment (Baroni and Orombelli, 1987; Baroni and others, 1995; Meneghel, 1999; Vassena and others., 2001). The Strandline Glacier (74 41 S; 164 07 E), in particular is a small alpine glacier (0,79 kmq) on the coast of Terra Nova Bay, Northern Victoria Land; it is a cold glacier where accumulation and ablation basins are mainly controlled by wind processes. Its terminus forms in the central part a grounded ice cliff about 30 m high, about 130 m far from the sea. On that glacier mass balance, surface velocity and calving rate were measured. During the southern summer season 2000-2001 many topographycal profiles of the ice cliff were surveyed by using both classical topographical and glaciological methods (total station and stakes) and GPS technique. It was so possible to detect the short term

  18. The 2016 gigantic twin glacier collapses in Tibet: towards an improved understanding of large glacier instabilities and their potential links to climate change

    Science.gov (United States)

    Gilbert, Adrien; Leinss, Silvan; Evans, Steve; Tian, Lide; Kääb, Andreas; Kargel, Jeffrey; Gimbert, Florent; Chao, Wei-An; Gascoin, Simon; Bueler, Yves; Berthier, Etienne; Yao, Tandong; Huggel, Christian; Farinotti, Daniel; Brun, Fanny; Guo, Wanqin; Leonard, Gregory

    2017-04-01

    In northwestern Tibet (34.0°N, 82.2°E) near lake Aru Co, the entire ablation area of an unnamed glacier (Aru-1) suddenly collapsed on 17 July 2016 and transformed into a mass flow that ran out over a distance of over 8 km, killing nine people and hundreds of cattle. Remarkably, a second glacier detachment with similar characteristics (Aru-2) took place 2.6 km south of the July event on 21 September 2016. These two events are unique in several aspects: their massive volumes (66 and 83 Mm3 respectively), the low slope angles ( 200 km h-1) and their close timing within two months. The only similar event currently documented is the 2002 Kolka Glacier mass flow (Caucasus Mountains). The uncommon occurrence of such large glacier failures suggest that such events require very specific conditions that could be linked to glacier thermal regime, bedrock lithology and morphology, geothermal activity or a particular climate setting. Using field and remote sensing observations, retrospective climate analysis, mass balance and thermo-mechanical modeling of the two glaciers in Tibet, we investigate the processes involved in the twin collapses. It appears that both, mostly cold-based glaciers, started to surge about 7-8 years ago, possibly in response to a long period of positive mass balance (1995-2005) followed by a sustained increase of melt water delivery to the glacier bed in the polythermal lower accumulation zone (1995-2016). Inversion of friction conditions at the base of the glacier constrained by surface elevation change rate for both glaciers shows a zone of very low basal friction progressively migrating downward until the final collapse. We interpret this to be the signature of the presence of high-pressure water dammed at the bed by the glacier's frozen periphery and toe. Large areas of low friction at the bed led to high shear stresses along the frozen side walls as evident in surface ice cracking patterns observed on satellite imagery. This process progressively

  19. Plutonium dissolution from Rocky Flats Plant incinerator ash

    International Nuclear Information System (INIS)

    Delegard, C.H.

    1985-06-01

    Rockwell Hanford Operations (Rockwell) soon will commence recovery of plutonium from Rocky Flats Plant incinerator ash. In preparation for this processing, Rockwell undertook literature and laboratory studies to identify, select and optimize plutonium dissolution methods for treating the ash. Ash reburning, followed by dissolution in nitric acid containing calcium fluoride, was selected as the processing method for the ash. Recommended values of process parameters were identified. Using the selected process, 99.5% plutonium recovery was achieved, leaving about 12.7 wt % heel residue for an equal weight composite of the three ashes tested. 15 refs., 26 figs

  20. Thermal Structure and Mantle Dynamics of Rocky Exoplanets

    Science.gov (United States)

    Wagner, F. W.; Tosi, N.; Hussmann, H.; Sohl, F.

    2011-12-01

    The confirmed detections of CoRoT-7b and Kepler-10b reveal that rocky exoplanets exist. Moreover, recent theoretical studies suggest that small planets beyond the Solar System are indeed common and many of them will be discovered by increasingly precise observational surveys in the years ahead. The knowledge about the interior structure and thermal state of exoplanet interiors provides crucial theoretical input not only for classification and characterization of individual planetary bodies, but also to better understand the origin and evolution of the Solar System and the Earth in general. These developments and considerations have motivated us to address several questions concerning thermal structure and interior dynamics of terrestrial exoplanets. In the present study, depth-dependent structural models of solid exoplanet interiors have been constructed in conjunction with a mixing length approach to calculate self-consistently the radial distribution of temperature and heat flux. Furthermore, 2-D convection simulations using the compressible anelastic approximation have been carried through to examine the effect of thermodynamic quantities (e.g., thermal expansivity) on mantle convection pattern within rocky planets more massive than the Earth. In comparison to parameterized convection models, our calculated results predict generally hotter planetary interiors, which are mainly attributed to a viscosity-regulating feedback mechanism involving temperature and pressure. We find that density and thermal conductivity increase with depth by a factor of two to three, however, thermal expansivity decreases by more than an order of magnitude across the mantle for planets as massive as CoRoT-7b or Kepler-10b. The specific heat capacity is observed to stay almost constant over an extended region of the lower mantle. The planform of mantle convection is strongly modified in the presence of depth-dependent thermodynamic quantities with hot upwellings (plumes) rising across

  1. The Rocky Flats Environmental Technology Site beryllium characterization project

    International Nuclear Information System (INIS)

    Morrell, D.M.; Miller, J.R.; Allen, D.F.

    1999-01-01

    A site beryllium characterization project was completed at the Rocky Flats Environmental Technology Site (RFETS) in 1997. Information from historical reviews, previous sampling surveys, and a new sampling survey were used to establish a more comprehensive understanding of the locations and levels of beryllium contamination in 35 buildings. A feature of the sampling strategy was to test if process knowledge was a good predictor of where beryllium contamination could be found. Results revealed that this technique was effective at identifying where surface contamination levels might exceed the RFETS smear control level but that it was not effective in identifying where low concentrations of beryllium might be found

  2. Recovery of plutonium from incinerator ash at Rocky Flats

    International Nuclear Information System (INIS)

    Johnson, T.C.

    1976-01-01

    Incineration of combustible materials highly contaminated with plutonium produces a residue of incinerator ash. Recovery of plutonium from incinerator ash residues at Rocky Flats is accomplished by a continuous leaching operation with nitric acid containing fluoride ion. Special equipment used in the leaching operation consists of a screw feeder, air-lift dissolvers, filters, solids dryer, and vapor collection system. Each equipment item is described in detail. The average dissolution efficiency of plutonium experienced with the process was 68% on the first pass, 74% on the second pass, and 64% on each subsequent pass. Total-solids dissolution efficiencies averaged 47% on the first pass and about 25% on each subsequent pass

  3. [Rocky mountain spotted fever: report of two cases].

    Science.gov (United States)

    Martínez-Medina, Miguel Angel; Padilla-Zamudio, Guillermo; Solís-Gallardo, Lilia Patricia; Guevara-Tovar, Marcela

    2005-01-01

    Rocky Mountain spotted fever (RMSF) is an acute febrile illness caused by infection with Ricketsia Rickettsii, characterized by the presence of petechial rash. Even though the etiology, clinical characteristics and availability of effective antibiotics are known, RMSF related deaths have a prevalence of 4%. In its early stages RMFS can resemble many others infectious conditions and the diagnosis can be difficult. The present paper reports two patients with RMSF; these cases underscore the importance of prompt diagnosis and appropriate antimicrobial therapy, and consider RMSF as a differential diagnosis in any patient who develops fever and rash in an endemic area.

  4. The prospects for Canadian uranium

    International Nuclear Information System (INIS)

    Salaff, S.

    1983-07-01

    The 1980s have seen a decline in markets for uranium concentrate, largely as a result of falling estimates for reactor fuel requirements and rising inventories. Spot market prices fell to $44 in September 1982, but have since risen back to $60. World production also fell in 1982 and is not expected to increase significantly before 1990. Some opportunities exist for Canadian producers with new low-cost deposits to replace high-cost producers in Canada and other countries, particularly the United States. There will be strong competition between Canadian producers as well as from Australia. Australia's reserves are somewhat larger than Canada's, although the reported ore grades tend to be lower than those of Saskatchewan

  5. Ice thickness profile surveying with ground penetrating radar at Artesonraju Glacier, Peru

    Science.gov (United States)

    Chisolm, Rachel; Rabatel, Antoine; McKinney, Daene; Condom, Thomas; Cochacin, Alejo; Davila Roller, Luzmilla

    2014-05-01

    Tropical glaciers are an essential component of the water resource systems in the mountainous regions where they are located, and a warming climate has resulted in the accelerated retreat of Andean glaciers in recent decades. The shrinkage of Andean glaciers influences the flood risk for communities living downstream as new glacial lakes have begun to form at the termini of some glaciers. As these lakes continue to grow in area and volume, they pose an increasing risk of glacial lake outburst floods (GLOFs). Ice thickness measurements have been a key missing link in studying the tropical glaciers in Peru and how climate change is likely to impact glacial melt and the growth of glacial lakes. Ground penetrating radar (GPR) has rarely been applied to glaciers in Peru to measure ice thickness, and these measurements can tell us a lot about how a warming climate will affect glaciers in terms of thickness changes. In the upper Paron Valley (Cordillera Blanca, Peru), an emerging lake has begun to form at the terminus of the Artesonraju Glacier, and this lake has key features, including overhanging ice and loose rock likely to create slides, that could trigger a catastrophic GLOF if the lake continues to grow. Because the glacier mass balance and lake mass balance are closely linked, ice thickness measurements and measurements of the bed slope of the Artesonraju Glacier and underlying bedrock can give us an idea of how the lake is likely to evolve in the coming decades. This study presents GPR data taken in July 2013 at the Artesonraju Glacier as part of a collaboration between the Unidad de Glaciologia y Recursos Hidricos (UGRH) of Peru, the Institut de Recherche pour le Développement (IRD) of France and the University of Texas at Austin (UT) of the United States of America. Two different GPR units belonging to UGRH and UT were used for subsurface imaging to create ice thickness profiles and to characterize the total volume of ice in the glacier. A common midpoint

  6. Air temperature, radiation budget and area changes of Quisoquipina glacier in the Cordillera Vilcanota (Peru)

    Science.gov (United States)

    Suarez, Wilson; Macedo, Nicolás; Montoya, Nilton; Arias, Sandro; Schauwecker, Simone; Huggel, Christian; Rohrer, Mario; Condom, Thomas

    2015-04-01

    The Peruvian Andes host about 71% of all tropical glaciers. Although several studies have focused on glaciers of the largest glaciered mountain range (Cordillera Blanca), other regions have received little attention to date. In 2011, a new program has been initiated with the aim of monitoring glaciers in the centre and south of Peru. The monitoring program is managed by the Servicio Nacional de Meteorología e Hidrología del Perú (SENAMHI) and it is a joint project together with the Universidad San Antonio Abad de Cusco (UNSAAC) and the Autoridad Nacional del Agua (ANA). In Southern Peru, the Quisoquipina glacier has been selected due to its representativeness for glaciers in the Cordillera Vilcanota considering area, length and orientation. The Cordillera Vilcanota is the second largest mountain range in Peru with a glaciated area of approximately 279 km2 in 2009. Melt water from glaciers in this region is partly used for hydropower in the dry season and for animal breeding during the entire year. Using Landsat 5 images, we could estimate that the area of Quisoquipina glacier has decreased by approximately 11% from 3.66 km2 in 1990 to 3.26 km2 in 2010. This strong decrease is comparable to observations of other tropical glaciers. In 2011, a meteorological station has been installed on the glacier at 5180 m asl., measuring air temperature, wind speed, relative humidity, net short and longwave radiation and atmospheric pressure. Here, we present a first analysis of air temperature and the radiation budget at the Quisoquipina glacier for the first three years of measurements. Additionally, we compare the results from Quisoquipina glacier to results obtained by the Institut de recherche pour le développement (IRD) for Zongo glacier (Bolivia) and Antizana glacier (Ecuador). For both, Quisoquipina and Zongo glacier, net shortwave radiation may be the most important energy source, thus indicating the important role of albedo in the energy balance of the glacier

  7. Copernicus Big Data and Google Earth Engine for Glacier Surface Velocity Field Monitoring: Feasibility Demonstration on San Rafael and San Quintin Glaciers

    Science.gov (United States)

    Di Tullio, M.; Nocchi, F.; Camplani, A.; Emanuelli, N.; Nascetti, A.; Crespi, M.

    2018-04-01

    The glaciers are a natural global resource and one of the principal climate change indicator at global and local scale, being influenced by temperature and snow precipitation changes. Among the parameters used for glacier monitoring, the surface velocity is a key element, since it is connected to glaciers changes (mass balance, hydro balance, glaciers stability, landscape erosion). The leading idea of this work is to continuously retrieve glaciers surface velocity using free ESA Sentinel-1 SAR imagery and exploiting the potentialities of the Google Earth Engine (GEE) platform. GEE has been recently released by Google as a platform for petabyte-scale scientific analysis and visualization of geospatial datasets. The algorithm of SAR off-set tracking developed at the Geodesy and Geomatics Division of the University of Rome La Sapienza has been integrated in a cloud based platform that automatically processes large stacks of Sentinel-1 data to retrieve glacier surface velocity field time series. We processed about 600 Sentinel-1 image pairs to obtain a continuous time series of velocity field measurements over 3 years from January 2015 to January 2018 for two wide glaciers located in the Northern Patagonian Ice Field (NPIF), the San Rafael and the San Quintin glaciers. Several results related to these relevant glaciers also validated with respect already available and renown software (i.e. ESA SNAP, CIAS) and with respect optical sensor measurements (i.e. LANDSAT8), highlight the potential of the Big Data analysis to automatically monitor glacier surface velocity fields at global scale, exploiting the synergy between GEE and Sentinel-1 imagery.

  8. Rainfall as primary driver of discharge and solute export from rock glaciers: The Col d'Olen Rock Glacier in the NW Italian Alps.

    Science.gov (United States)

    Colombo, Nicola; Gruber, Stephan; Martin, Maria; Malandrino, Mery; Magnani, Andrea; Godone, Danilo; Freppaz, Michele; Fratianni, Simona; Salerno, Franco

    2018-10-15

    Three hypotheses exist to explain how meteorological variables drive the amount and concentration of solute-enriched water from rock glaciers: (1) Warm periods cause increased subsurface ice melt, which releases solutes; (2) rain periods and the melt of long-lasting snow enhance dilution of rock-glacier outflows; and (3) percolation of rain through rock glaciers facilitates the export of solutes, causing an opposite effect as that described in hypothesis (2). This lack of detailed understanding likely exists because suitable studies of meteorological variables, hydrologic processes and chemical characteristics of water bodies downstream from rock glaciers are unavailable. In this study, a rock-glacier pond in the North-Western Italian Alps was studied on a weekly basis for the ice-free seasons 2014 and 2015 by observing the meteorological variables (air temperature, snowmelt, rainfall) assumed to drive the export of solute-enriched waters from the rock glacier and the hydrochemical response of the pond (water temperature as a proxy of rock-glacier discharge, stable water isotopes, major ions and selected trace elements). An intra-seasonal pattern of increasing solute export associated with higher rock-glacier discharge was found. Specifically, rainfall, after the winter snowpack depletion and prolonged periods of atmospheric temperature above 0 °C, was found to be the primary driver of solute export from the rock glacier during the ice-free season. This occurs likely through the flushing of isotopically- and geochemically-enriched icemelt, causing concomitant increases in the rock-glacier discharge and the solute export (SO 4 2- , Mg 2+ , Ca 2+ , Ni, Mn, Co). Moreover, flushing of microbially-active sediments can cause increases in NO 3 - export. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Canadian wind energy industry directory

    International Nuclear Information System (INIS)

    1996-01-01

    The companies and organizations involved, either directly or indirectly, in the wind energy industry in Canada, are listed in this directory. Some U.S. and international companies which are active or interested in Canadian industry activities are also listed. The first section of the directory is an alphabetical listing which includes corporate descriptions, company logos, addresses, phone and fax numbers, e-mail addresses and contact names. The second section contains 54 categories of products and services associated with the industry

  10. Canadian Petroleum Association statistical handbook

    International Nuclear Information System (INIS)

    1992-04-01

    Statistical data are presented for the Canadian oil and gas industry for 1991, with some historical and background data included. Tables are provided on land sales and holdings, drilling completions, reserves, production, inventories, production capacity, cash expenditures, value of sales, prices, consumption, sales, refinery capacity and utilization, refinery yields, pipelines, imports and exports, National Energy Board licenses and orders, electricity generation capacity, and supply and disposal of electric energy. 112 tabs

  11. Exporting the Canadian licensing program

    International Nuclear Information System (INIS)

    Whelan, D.J.

    1981-06-01

    This paper deals with the problems of an overseas regulatory agency in licensing a Canadian-supplied nuclear plant which is referenced to a plant in Canada. Firstly, the general problems associated with the use of a reference plant are discussed. This is followed by a discussion of specific problems which arise from the licensing practices in Canada. The paper concludes with recommendations to simplify the task of demonstrating the licensability of an overseas CANDU plant

  12. Canadian accelerator breeder system development

    International Nuclear Information System (INIS)

    Schriber, S.O.

    1982-11-01

    A shortage of fissile material at a reasonable price is expected to occur in the early part of the twenty-first century. Converting fertile material to fissile material by electronuclar methods is an option that can extend th world's resources of fissionable material, supplying fuel for nuclear power stations. This paper presents the rationale for electronuclear breeders and describes the Canadian development program for an accelerator breeder facility that could produce 1 Mg of fissile material per year

  13. A history of forest entomology in the Intermountain and Rocky Mountain areas, 1901 to 1982

    Science.gov (United States)

    Malcolm M. Furniss

    2007-01-01

    This account spans the time from A.D. Hopkins' trip to the Black Hills, SD, in 1901 to my retirement in 1982. The focus is on personnel and the work of the Division of Forest Insect Investigations, USDA, and the Forest Service experiment stations in the Rocky Mountain and Intermountain areas. Information for the Intermountain and Northern Rocky Mountain station...

  14. 76 FR 9350 - Patient Safety Organizations: Voluntary Delisting From Rocky Mountain Patient Safety Organization

    Science.gov (United States)

    2011-02-17

    ... Organizations: Voluntary Delisting From Rocky Mountain Patient Safety Organization AGENCY: Agency for Healthcare... Organization: AHRQ has accepted a notification of voluntary relinquishment from Rocky Mountain Patient Safety Organization, a component entity of Colorado Hospital Association, of its status as a Patient Safety...

  15. 78 FR 70033 - Encana Marketing (USA) Inc. v. Rockies Express Pipeline LLC; Notice of Complaint

    Science.gov (United States)

    2013-11-22

    ... Marketing (USA) Inc. v. Rockies Express Pipeline LLC; Notice of Complaint Take notice that on November 15... Commission (Commission), 18 CFR 385.206, Encana Marketing (USA) Inc. (Encana Marketing or Complainant), filed... Rockies Express has unlawfully denied Encana Marketing's request to make changes to the primary delivery...

  16. Cascading effects of fire exclusion in the Rocky Mountain ecosystems: a literature review

    Science.gov (United States)

    Robert E. Keane; Kevin C. Ryan; Tom T. Veblen; Craig D. Allen; Jessie Logan; Brad Hawkes

    2002-01-01

    The health of many Rocky Mountain ecosystems is in decline because of the policy of excluding fire in the management of these ecosystems. Fire exclusion has actually made it more difficult to fight fires, and this poses greater risks to the people who fight fires and for those who live in and around Rocky Mountain forests and rangelands. This paper discusses the extent...

  17. Vascular plant flora of the alpine zone in the southern Rocky Mountains, U.S.A

    Science.gov (United States)

    James F. Fowler; B. E. Nelson; Ronald L. Hartman

    2014-01-01

    Field detection of changes in occurrence, distribution, or abundance of alpine plant species is predicated on knowledge of which species are in specific locations. The alpine zone of the Southern Rocky Mountain Region has been systematically inventoried by the staff and floristics graduate students from the Rocky Mountain Herbarium over the last 27 years. It is...

  18. Co-Infection of Rickettsia rickettsii and Streptococcus pyogenes: Is Fatal Rocky Mountain Spotted Fever Underdiagnosed?

    Science.gov (United States)

    Raczniak, Gregory A.; Kato, Cecilia; Chung, Ida H.; Austin, Amy; McQuiston, Jennifer H.; Weis, Erica; Levy, Craig; Carvalho, Maria da Gloria S.; Mitchell, Audrey; Bjork, Adam; Regan, Joanna J.

    2014-01-01

    Rocky Mountain spotted fever, a tick-borne disease caused by Rickettsia rickettsii, is challenging to diagnose and rapidly fatal if not treated. We describe a decedent who was co-infected with group A β-hemolytic streptococcus and R. rickettsii. Fatal cases of Rocky Mountain spotted fever may be underreported because they present as difficult to diagnose co-infections. PMID:25331804

  19. Inverse vertical migration and feeding in glacier lanternfish (Benthosema glaciale)

    KAUST Repository

    Dypvik, Eivind

    2011-11-08

    A bottom-mounted upward-facing 38-kHz echo sounder was deployed at ~400 m and cabled to shore in Masfjorden (~60 52?N, ~5 24?E), Norway. The scattering layers seen during autumn (September-October) 2008 were identified by trawling. Glacier lanternfish (Benthosema glaciale) were mainly distributed below ~200 m and displayed three different diel behavioral strategies: normal diel vertical migration (NDVM), inverse DVM (IDVM) and no DVM (NoDVM). The IDVM group was the focus of this study. It consisted of 2-year and older individuals migrating to ~200-270 m during the daytime, while descending back to deeper than ~270 m during the night. Stomach content analysis revealed increased feeding during the daytime on overwintering Calanus sp. We conclude that visually searching glacier lanternfish performing IDVM benefit from the faint daytime light in mid-waters when preying on overwintering Calanus sp. 2011 The Author(s).

  20. Investigating the Equatorial Gaps in Snowball Earth Sea Glaciers

    Science.gov (United States)

    Spaulding-Astudillo, F.; Ashkenazy, Y.; Tziperman, E.; Abbot, D. S.

    2017-12-01

    The way photosynthetic life survived the Neoproterozoic Snowball Earth events is still a matter of debate that has deep implications for planetary habitability. One option is that gaps in thick, semi-global ice coverage (sea glaciers) could be maintained at the equator by ocean-ice-atmosphere dynamics. We investigate this idea by modifying a global ocean-thick-marine-ice model developed for modeling Neoproterozoic Snowball Events to account for gaps in thick ice and interactions with atmospheric dynamics. Our hypothesis is that in the parameter regime that allows for sea glacier flow, ice flow will make gaps in the thick ice, and therefore an open ocean solution, less likely. This would suggest that oases in thick ice are a more viable survival mechanism for photosynthetic life during a Snowball Earth event.

  1. New eyes in the sky measure glaciers and ice sheets

    Science.gov (United States)

    Kieffer, Hugh; Kargel, Jeffrey S.; Barry, Roger G.; Bindschadler, Robert; Bishop, Michael P.; MacKinnon, David; Ohmura, Atsumu; Raup, Bruce; Antoninetti, Massimo; Bamber, Jonathan; Braun, Mattias; Brown, Ian; Cohen, Denis; Copland, Luke; DueHagen, Jon; Engeset, Rune V.; Fitzharris, Blair; Fujita, Koji; Haeberli, Wilfried; Hagen, Jon Oue; Hall, Dorothy; Hoelzle, Martin; Johansson, Maria; Kaab, Andi; Koenig, Max; Konovalov, Vladimir; Maisch, Max; Paul, Frank; Rau, Frank; Reeh, Niels; Rignot, Eric; Rivera, Andres; De Ruyter de Wildt, Martiyn; Scambos, Ted; Schaper, Jesko; Scharfen, Greg; Shroder, Jack; Solomina, Olga; Thompson, David; van der Veen, Kees; Wohlleben, Trudy; Young, Neal

    2000-01-01

    The mapping and measurement of glaciers and their changes are useful in predicting sea-level and regional water supply, studying hazards and climate change [Haeberli et al., 1998],and in the hydropower industry Existing inventories cover only about 67,000 of the world's estimated 160,000 glaciers and are based on data collected over 50 years or more [e.g.,Haeberli et al., 1998]. The data available have proven that small ice bodies are disappearing at an accelerating rate and that the Antarctic ice sheet and its fringing ice shelves are undergoing unexpected, rapid change. According to many glaciologists, much larger fluctuations in land ice—with vast implications for society—are possible in the coming decades and centuries due to natural and anthropogenic climate change [Oppenheimer, 1998].

  2. Providing cleaner air to Canadians

    International Nuclear Information System (INIS)

    2001-02-01

    This booklet is designed to explain salient aspects of the Ozone Annex, negotiated and signed recently by Canada and the United States, in a joint effort to improve air quality in North America. By significantly reducing the transboundary flows of air pollutants that cause smog, the Ozone Annex will benefit some 16 million people in central and eastern Canada and provide an example for a future round of negotiations to address concerns of the millions of Canadians and Americans who live in the border area between British Columbia and Washington State. The brochure provide summaries of the Canadian and American commitments, focusing on transportation, monitoring and reporting. The Ozone Annex complements other air quality initiatives by the Government of Canada enacted under the Environmental Protection Act, 1999. These measures include regulations to reduce sulphur content to 30 parts per million by Jan 1, 2005; proposing to restrict toxic particulate matter (PM) to less than 10 microns; establishing daily smog forecasts in the Maritimes and committing to a national program built upon existing smog advisories and forecasts in Quebec, Ontario and British Columbia; and investing in more clean air research through the newly created Canadian Foundation for Climate and Atmospheric Sciences

  3. Canadian fusion fuels technology project

    International Nuclear Information System (INIS)

    1986-01-01

    The Canadian Fusion Fuels Technology Project was launched in 1982 to coordinate Canada's provision of fusion fuels technology to international fusion power development programs. The project has a mandate to extend and adapt existing Canadian tritium technologies for use in international fusion power development programs. 1985-86 represents the fourth year of the first five-year term of the Canadian Fusion Fuels Technology Project (CFFTP). This reporting period coincides with an increasing trend in global fusion R and D to direct more effort towards the management of tritium. This has resulted in an increased linking of CFFTP activities and objectives with those of facilities abroad. In this way there has been a continuing achievement resulting from CFFTP efforts to have cooperative R and D and service activities with organizations abroad. All of this is aided by the cooperative international atmosphere within the fusion community. This report summarizes our past year and provides some highlights of the upcoming year 1986/87, which is the final year of the first five-year phase of the program. AECL (representing the Federal Government), the Ministry of Energy (representing Ontario) and Ontario Hydro, have given formal indication of their intent to continue with a second five-year program. Plans for the second phase will continue to emphasize tritium technology and remote handling

  4. Mercury in Canadian crude oil

    International Nuclear Information System (INIS)

    Hollebone, B.P.

    2005-01-01

    Estimates for average mercury concentrations in crude oil range widely from 10 ng/g of oil to 3,500 ng/g of oil. With such a broad range of estimates, it is difficult to determine the contributions of the petroleum sector to the total budget of mercury emissions. In response to concerns that the combustion of petroleum products may be a major source of air-borne mercury pollution, Environment Canada and the Canadian Petroleum Products Institute has undertaken a survey of the average total mercury concentration in crude oil processed in Canadian refineries. In order to calculate the potential upper limit of total mercury in all refined products, samples of more than 30 different types of crude oil collected from refineries were measured for their concentration of mercury as it enters into a refinery before processing. High temperature combustion, cold vapour atomic absorption and cold vapour atomic fluorescence were the techniques used to quantify mercury in the samples. The results of the study provide information on the total mass of mercury present in crude oil processed in Canada each year. Results can be used to determine the impact of vehicle exhaust emissions to the overall Canadian mercury emission budget. 17 refs., 2 tabs., 2 figs

  5. Reliability issues : a Canadian perspective

    International Nuclear Information System (INIS)

    Konow, H.

    2004-01-01

    A Canadian perspective of power reliability issues was presented. Reliability depends on adequacy of supply and a framework for standards. The challenges facing the electric power industry include new demand, plant replacement and exports. It is expected that demand will by 670 TWh by 2020, with 205 TWh coming from new plants. Canada will require an investment of $150 billion to meet this demand and the need is comparable in the United States. As trade grows, the challenge becomes a continental issue and investment in the bi-national transmission grid will be essential. The 5 point plan of the Canadian Electricity Association is to: (1) establish an investment climate to ensure future electricity supply, (2) move government and industry towards smart and effective regulation, (3) work to ensure a sustainable future for the next generation, (4) foster innovation and accelerate skills development, and (5) build on the strengths of an integrated North American system to maximize opportunity for Canadians. The CEA's 7 measures that enhance North American reliability were listed with emphasis on its support for a self-governing international organization for developing and enforcing mandatory reliability standards. CEA also supports the creation of a binational Electric Reliability Organization (ERO) to identify and solve reliability issues in the context of a bi-national grid. tabs., figs

  6. Passive seismic monitoring of the Bering Glacier during its last surge event

    Science.gov (United States)

    Zhan, Z.

    2017-12-01

    The physical causes behind glacier surges are still unclear. Numerous evidences suggest that they probably involve changes in glacier basal conditions, such as switch of basal water system from concentrated large tunnels to a distributed "layer" as "connected cavities". However, most remote sensing approaches can not penetrate to the base to monitor such changes continuously. Here we apply seismic interferometry using ambient noise to monitor glacier seismic structures, especially to detect possible signatures of the hypothesized high-pressure water "layer". As an example, we derive an 11-year long history of seismic structure of the Bering Glacier, Alaska, covering its latest surge event. We observe substantial drops of Rayleigh and Love wavespeeds across the glacier during the surge event, potentially caused by changes in crevasse density, glacier thickness, and basal conditions.

  7. A GIS tool for two-dimensional glacier-terminus change tracking

    Science.gov (United States)

    Urbanski, Jacek Andrzej

    2018-02-01

    This paper presents a Glacier Termini Tracking (GTT) toolbox for the two-dimensional analysis of glacier-terminus position changes. The input consists of a vector layer with several termini lines relating to the same glacier at different times. The output layers allow analyses to be conducted of glacier-terminus retreats, changes in retreats over time and along the ice face, and glacier-terminus fluctuations over time. The application of three tools from the toolbox is demonstrated via the analysis of eight glacier-terminus retreats and fluctuations at the Hornsund fjord in south Svalbard. It is proposed that this toolbox may also be useful in the study of other line features that change over time, like coastlines and rivers. The toolbox has been coded in Python and runs via ArcGIS.

  8. Boundary layer models for calving marine outlet glaciers

    Directory of Open Access Journals (Sweden)

    C. Schoof

    2017-10-01

    Full Text Available We consider the flow of marine-terminating outlet glaciers that are laterally confined in a channel of prescribed width. In that case, the drag exerted by the channel side walls on a floating ice shelf can reduce extensional stress at the grounding line. If ice flux through the grounding line increases with both ice thickness and extensional stress, then a longer shelf can reduce ice flux by decreasing extensional stress. Consequently, calving has an effect on flux through the grounding line by regulating the length of the shelf. In the absence of a shelf, it plays a similar role by controlling the above-flotation height of the calving cliff. Using two calving laws, one due to Nick et al. (2010 based on a model for crevasse propagation due to hydrofracture and the other simply asserting that calving occurs where the glacier ice becomes afloat, we pose and analyse a flowline model for a marine-terminating glacier by two methods: direct numerical solution and matched asymptotic expansions. The latter leads to a boundary layer formulation that predicts flux through the grounding line as a function of depth to bedrock, channel width, basal drag coefficient, and a calving parameter. By contrast with unbuttressed marine ice sheets, we find that flux can decrease with increasing depth to bedrock at the grounding line, reversing the usual stability criterion for steady grounding line location. Stable steady states can then have grounding lines located on retrograde slopes. We show how this anomalous behaviour relates to the strength of lateral versus basal drag on the grounded portion of the glacier and to the specifics of the calving law used.

  9. Enhanced ASTER DEMs for Decadal Measurements of Glacier Elevation Changes

    Science.gov (United States)

    Girod, L.; Nuth, C.; Kääb, A.

    2016-12-01

    Elevation change data is critical to the understanding of a number of geophysical processes, including glaciers through the measurement their volume change. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) system on-board the Terra (EOS AM-1) satellite has been a unique source of systematic stereoscopic images covering the whole globe at 15m resolution and at a consistent quality for over 15 years. While satellite stereo sensors with significantly improved radiometric and spatial resolution are available today, the potential of ASTER data lies in its long consistent time series that is unrivaled, though not fully exploited for change analysis due to lack of data accuracy and precision. ASTER data are strongly affected by attitude jitter, mainly of approximately 4 and 30 km wavelength, and improving the generation of ASTER DEMs requires removal of this effect. We developed MMASTER, an improved method for ASTER DEM generation and implemented it in the open source photogrammetric library and software suite MicMac. The method relies on the computation of a rational polynomial coefficients (RPC) model and the detection and correction of cross-track sensor jitter in order to compute DEMs. Our sensor modeling does not require ground control points and thus potentially allows for automatic processing of large data volumes. When compared to ground truth data, we have assessed a ±5m accuracy in DEM differencing when using our processing method, improved from the ±30m when using the AST14DMO DEM product. We demonstrate and discuss this improved ASTER DEM quality for a number of glaciers in Greenland (See figure attached), Alaska, and Svalbard. The quality of our measurements promises to further unlock the underused potential of ASTER DEMs for glacier volume change time series on a global scale. The data produced by our method will thus help to better understand the response of glaciers to climate change and their influence on runoff and sea level.

  10. Extraction of Rocky Desertification from Disp Imagery: a Case Study of Liupanshui, Guizhou, China

    Science.gov (United States)

    Zhou, G.; Wu, Z.; Wang, W.; Shi, Y.; Mao, G.; Huang, Y.; Jia, B.; Gao, G.; Chen, P.

    2017-09-01

    Karst rocky desertification is a typical type of land degradation in Guizhou Province, China. It causes great ecological and economical implications to the local people. This paper utilized the declassified intelligence satellite photography (DISP) of 1960s to extract the karst rocky desertification area to analyze the early situation of karst rocky desertification in Liupanshui, Guizhou, China. Due to the lack of ground control points and parameters of the satellite, a polynomial orthographic correction model with considering altitude difference correction is proposed for orthorectification of DISP imagery. With the proposed model, the 96 DISP images from four missions are orthorectified. The images are assembled into a seamless image map of the karst area of Guizhou, China. The assembled image map is produced to thematic map of karst rocky desertification by visual interpretation in Liupanshui city. With the assembled image map, extraction of rocky desertification is conducted.

  11. EXTRACTION OF ROCKY DESERTIFICATION FROM DISP IMAGERY: A CASE STUDY OF LIUPANSHUI, GUIZHOU, CHINA

    Directory of Open Access Journals (Sweden)

    G. Zhou

    2017-09-01

    Full Text Available Karst rocky desertification is a typical type of land degradation in Guizhou Province, China. It causes great ecological and economical implications to the local people. This paper utilized the declassified intelligence satellite photography (DISP of 1960s to extract the karst rocky desertification area to analyze the early situation of karst rocky desertification in Liupanshui, Guizhou, China. Due to the lack of ground control points and parameters of the satellite, a polynomial orthographic correction model with considering altitude difference correction is proposed for orthorectification of DISP imagery. With the proposed model, the 96 DISP images from four missions are orthorectified. The images are assembled into a seamless image map of the karst area of Guizhou, China. The assembled image map is produced to thematic map of karst rocky desertification by visual interpretation in Liupanshui city. With the assembled image map, extraction of rocky desertification is conducted.

  12. Surge dynamics on Bering Glacier, Alaska, in 2008–2011

    Directory of Open Access Journals (Sweden)

    M. Braun

    2012-11-01

    Full Text Available A surge cycle of the Bering Glacier system, Alaska, is examined using observations of surface velocity obtained using synthetic aperture radar (SAR offset tracking, and elevation data obtained from the University of Alaska Fairbanks LiDAR altimetry program. After 13 yr of quiescence, the Bering Glacier system began to surge in May 2008 and had two stages of accelerated flow. During the first stage, flow accelerated progressively for at least 10 months and reached peak observed velocities of ~ 7 m d−1. The second stage likely began in 2010. By 2011 velocities exceeded 9 m d−1 or ~ 18 times quiescent velocities. Fast flow continued into July 2011. Surface morphology indicated slowing by fall 2011; however, it is not entirely clear if the surge is yet over. The quiescent phase was characterized by small-scale acceleration events that increased driving stresses up to 70%. When the surge initiated, synchronous acceleration occurred throughout much of the glacier length. Results suggest that downstream propagation of the surge is closely linked to the evolution of the driving stress during the surge, because driving stress appears to be tied to the amount of resistive stress provided by the bed. In contrast, upstream acceleration and upstream surge propagation is not dependent on driving stress evolution.

  13. Glacier Snowline Determination from Terrestrial Laser Scanning Intensity Data

    Directory of Open Access Journals (Sweden)

    Hannah Prantl

    2017-07-01

    Full Text Available Accurately identifying the extent of surface snow cover on glaciers is important for extrapolating end of year mass balance measurements, constraining the glacier surface radiative energy balance and evaluating model simulations of snow cover. Here, we use auxiliary information from Riegl VZ-6000 Terrestrial Laser Scanner (TLS return signals to accurately map the snow cover over a glacier throughout an ablation season. Three classification systems were compared, and we find that supervised classification based on TLS signal intensity alone is outperformed by a rule-based classification employing intensity, surface roughness and an associated optical image, which achieves classification accuracy of 68–100%. The TLS intensity signal shows no meaningful relationship with surface or bulk snow density. Finally, we have also compared our Snow Line Altitude (SLA derived from TLS with SLA derived from the model output, as well as one Landsat image. The results of the model output track the SLA from TLS well, however with a positive bias. In contrast, automatic Landsat-derived SLA slightly underestimates the SLA from TLS. To conclude, we demonstrate that the snow cover extent can be mapped successfully using TLS, although the snow mass remains elusive.

  14. Assessing streamflow sensitivity to variations in glacier mass balance

    Science.gov (United States)

    O'Neel, Shad; Hood, Eran; Arendt, Anthony; Sass, Louis

    2014-01-01

    The mountains ringing the Gulf of Alaska (GOA) receive upwards of 4–8 m yr−1 of precipitation (Simpson et al.2005; Weingartner et al. 2005; O’Neel 2012), much of which runs off into productive coastal waters. The alpine landscape is heavily glacierized, and storage and turnover of water by glaciers substantially influences the regional surface water balance (Neal et al. 2010). In turn, the land-to-ocean flux of freshwater impacts the biogeochemistry, physical oceanography, freshwater and marine ecology of the downstream components of the GOA ecosystem (e.g., Royer et al. 2001; Hood and Scott 2008). In this way, the links between terrestrial and ocean ecosystems along the GOA have widespread impacts on regional socioeconomic issues including water and hydropower resources, fish populations, and sea level change (Dorava and Milner 2000; Royer and Grosch 2006; Cherry et al. 2010; Gardner et al. 2013). Moreover, predicting future changes in physical, chemical and biological processes in near-shore ecosystems along the GOA hinges, in part, on developing a robust understanding of water storage and transfer by glaciers through streams to the ocean.

  15. Retreat of Stephenson Glacier, Heard Island, from Remote Sensing and Field Observations

    Science.gov (United States)

    Mitchell, W.; Schmieder, R.

    2017-12-01

    Heard Island (Australian sub-Antarctic territory, 53 S, 73.5 E) is a volcanic island mantled in glaciers, and a UNESCO World Heritage Site both for its geology and ecology. Lying to the south of the Antarctic Convergence, the changes in response to climate seen on Heard Island are likely to be a bellwether for areas further south. Beginning in 1999, American satellites (Landsat 7, EO-1, and Landsat 8) have produced images of the island on a roughly weekly basis. Although the island is often shrouded in clouds, clear images of at least portions of the island are plentiful enough to create a nearly-annual record of the toe of Stephenson Glacier. During this period, Stephenson Glacier retreated by nearly 5 km, and lost 50% of its area. As a result of this retreat, a portion of the glacier now could be classified as a separate glacier. Additionally, in 2016, terrestrial photographs of Stephenson Glacier were taken during a three-week expedition to Heard Island, which accessed the Stephenson Glacier area by boat via the proglacial Stephenson Lagoon. During that work, sonar indicated some depths in the lagoon exceeding 100 m. Much of the loss in glacier length and area occurred during the mid- and late-2000s, with retreat rates slowing toward 2017. At this time, the glacier has retreated so that the main toe is not far from the base of a tall ice falls, while another toe—perhaps now a separate glacier—is land-based. This type of retreat pattern, fast over water and slower on land, is typical of other tidewater glaciers. Further monitoring of Stephenson Glacier and other glaciers on Heard Island will continue using Landsat 8.

  16. Instruments and Methods: A Low-Cost Glacier-Mapping System

    DEFF Research Database (Denmark)

    Christensen, Erik Lintz; Reeh, Niels; Forsberg, René

    2000-01-01

    the capability of acquiring accurate data on location and ice-surface elevation, and adequate-quality data on ice thickness. The system has been applied successfully in mapping the Nioghalvfjerdsfjorden glacier, northeast Greenland, in spite of the difficult conditions with melting water on the glacier surface....... The measurements from the floating part of the glacier have been evaluated by comparison of radar data with laser-altimeter and in situ measurements....

  17. Review article: Hydrological modeling in glacierized catchments of central Asia – status and challenges

    OpenAIRE

    Y. Chen; W. Li; G. Fang; Z. Li

    2017-01-01

    Meltwater from glacierized catchments is one of the most important water supplies in central Asia. Therefore, the effects of climate change on glaciers and snow cover will have increasingly significant consequences for runoff. Hydrological modeling has become an indispensable research approach to water resources management in large glacierized river basins, but there is a lack of focus in the modeling of glacial discharge. This paper reviews the status of hydrological modeli...

  18. Comparison of tropical and subtropical glacier surface energy balance in Africa and South America

    Science.gov (United States)

    Nicholson, L.; Prinz, R.; Kinnard, C.; Mölg, T.; Winkler, M.; Kaser, G.

    2010-05-01

    Tropical glaciers exist only at high altitude, and meteorological and surface energy balance studies of these glaciers can tell us much about the conditions and changes occurring in the mid troposphere. Understanding the surface energy balance and resultant mass balance regime of tropical glaciers is prerequisite to predicting glacier evolution, and future meltwater contributions to local hydrological resources, in response to future climate scenarios. Tropical glacier mass balance variability is strongly linked to precipitation and, via this, to multi-annual climate oscillations such as ENSO and IOZM, so it is useful to understand what role these differing regional influences play in comparison to the similarities imposed by the overarching tropical climate conditions and seasonality. New surface energy balance and mass balance data is available from Lewis glacier (Kenya, 0°09' S; 37°18' E), and here we use an energy and mass balance model to determine the surface energy flux characteristics at this site through a wet and dry season. Results are compared with those from Kersten glacier (Tanzania, 3°04' S; 37°21' E) to understand how conditions at these two glaciers compare and thus what coherent and contrasting climatic information glaciological records from these two sites can be expected to deliver. Meteorological data available from glacier stations on Antizana (Ecuador, 0°25' S; 78°09' W), Artesonraju (Peru, 8°28' S; 77°38' W) Zongo (Bolivia, 16°39' S; 67°47' W) and Guanaco (Chile, 29°20' S; 70°00' W) glaciers in South America offer the opportunity to examine how the surface fluxes and seasonal variability of the energy balance compares to those of the African glaciers. We include the extra-tropical Chilean example for comparison with the similarly high altitude, cold ice of Kersten glacier.

  19. Historical glacier outlines from digitized topographic maps of the Swiss Alps

    Science.gov (United States)

    Freudiger, Daphné; Mennekes, David; Seibert, Jan; Weiler, Markus

    2018-04-01

    Since the end of the Little Ice Age around 1850, the total glacier area of the central European Alps has considerably decreased. In order to understand the changes in glacier coverage at various scales and to model past and future streamflow accurately, long-term and large-scale datasets of glacier outlines are needed. To fill the gap between the morphologically reconstructed glacier outlines from the moraine extent corresponding to the time period around 1850 and the first complete dataset of glacier areas in the Swiss Alps from aerial photographs in 1973, glacier areas from 80 sheets of a historical topographic map (the Siegfried map) were manually digitized for the publication years 1878-1918 (further called first period, with most sheets being published around 1900) and 1917-1944 (further called second period, with most sheets being published around 1935). The accuracy of the digitized glacier areas was then assessed through a two-step validation process: the data were (1) visually and (2) quantitatively compared to glacier area datasets of the years 1850, 1973, 2003, and 2010, which were derived from different sources, at the large scale, basin scale, and locally. The validation showed that at least 70 % of the digitized glaciers were comparable to the outlines from the other datasets and were therefore plausible. Furthermore, the inaccuracy of the manual digitization was found to be less than 5 %. The presented datasets of glacier outlines for the first and second periods are a valuable source of information for long-term glacier mass balance or hydrological modelling in glacierized basins. The uncertainty of the historical topographic maps should be considered during the interpretation of the results. The datasets can be downloaded from the FreiDok plus data repository (https://freidok.uni-freiburg.de/data/15008" target="_blank">https://freidok.uni-freiburg.de/data/15008, https://doi.org/10.6094/UNIFR/15008" target="_blank">https://doi.org/10.6094/UNIFR

  20. Terricolous Lichens in the Glacier Forefield of the Pasterze (Eastern Alps, Carinthia, Austria)

    Science.gov (United States)

    Bilovitz, Peter O.; Wallner, Anja; Tutzer, Veronika; Nascimbene, Juri; Mayrhofer, Helmut

    2016-01-01

    Summary The investigation of lichens on soil, plant debris and terricolous mosses in the glacier forefield of the Pasterze yielded 35 lichen species. Placidiopsis oreades Breuss (Verrucariales) is new to Austria. Three sampling sites were established at increasing distance from the glacier, in order to compare species diversity, abundance and composition within the forefield and with four other glacier forefields of the Eastern Alps. PMID:26877565

  1. IceTrendr: a linear time-series approach to monitoring glacier environments using Landsat

    Science.gov (United States)

    Nelson, P.; Kennedy, R. E.; Nolin, A. W.; Hughes, J. M.; Braaten, J.

    2017-12-01

    Arctic glaciers in Alaska and Canada have experienced some of the greatest ice mass loss of any region in recent decades. A challenge to understanding these changing ecosystems, however, is developing globally-consistent, multi-decadal monitoring of glacier ice. We present a toolset and approach that captures, labels, and maps glacier change for use in climate science, hydrology, and Earth science education using Landsat Time Series (LTS). The core step is "temporal segmentation," wherein a yearly LTS is cleaned using pre-processing steps, converted to a snow/ice index, and then simplified into the salient shape of the change trajectory ("temporal signature") using linear segmentation. Such signatures can be characterized as simple `stable' or `transition of glacier ice to rock' to more complex multi-year changes like `transition of glacier ice to debris-covered glacier ice to open water to bare rock to vegetation'. This pilot study demonstrates the potential for interactively mapping, visualizing, and labeling glacier changes. What is truly innovative is that IceTrendr not only maps the changes but also uses expert knowledge to label the changes and such labels can be applied to other glaciers exhibiting statistically similar temporal signatures. Our key findings are that the IceTrendr concept and software can provide important functionality for glaciologists and educators interested in studying glacier changes during the Landsat TM timeframe (1984-present). Issues of concern with using dense Landsat time-series approaches for glacier monitoring include many missing images during the period 1984-1995 and that automated cloud mask are challenged and require the user to manually identify cloud-free images. IceTrendr is much more than just a simple "then and now" approach to glacier mapping. This process is a means of integrating the power of computing, remote sensing, and expert knowledge to "tell the story" of glacier changes.

  2. Dust Allergens within Rural Northern Rocky Mountain Residences.

    Science.gov (United States)

    Weiler, Emily; Semmens, Erin; Noonan, Curtis; Cady, Carol; Ward, Tony

    2015-01-23

    To date, few studies have characterized allergens within residences located in rural areas of the northern Rocky Mountain region. In this study, we collected dust samples from 57 homes located throughout western Montana and northern Idaho. Dust samples were collected and later analyzed for dust mite allergens Der f 1 and Der p 1 , Group 2 mite allergens ( Der p 2 and Der f 2 ), domestic feline ( Fel d 1 ), and canine ( Can f 1 ). Indoor temperature and humidity levels were also measured during the sampling program, as were basic characteristics of each home. Dog (96%) and cat (82%) allergens were the most prevalent allergens found in these homes (even when a feline or canine did not reside in the home). Results also revealed the presence of dust mites. Seven percent (7%) of homes tested positive for Der p 1 , 19% of homes were positive for Der f 1 , and 5% of homes were positive for the Group 2 mite allergens. Indoor relative humidity averaged 27.0 ± 7.6% within the homes. Overall, humidity was not significantly associated with dust mite presence, nor was any of the other measured home characteristics. This study provides a descriptive assessment of indoor allergen presence (including dust mites) in rural areas of the northern Rocky Mountains, and provides new information to assist regional patients with reducing allergen exposure using in-home intervention strategies.

  3. ROCKY EXTRASOLAR PLANETARY COMPOSITIONS DERIVED FROM EXTERNALLY POLLUTED WHITE DWARFS

    International Nuclear Information System (INIS)

    Klein, B.; Jura, M.; Zuckerman, B.; Koester, D.

    2011-01-01

    We report Keck High Resolution Echelle Spectrometer data and model atmosphere analysis of two helium-dominated white dwarfs, PG1225–079 and HS2253+8023, whose heavy pollutions most likely derive from the accretion of terrestrial-type planet(esimal)s. For each system, the minimum accreted mass is ∼10 22 g, that of a large asteroid. In PG1225–079, Mg, Cr, Mn, Fe, and Ni have abundance ratios similar to bulk Earth values, while we measure four refractory elements, Ca, Sc, Ti, and V, all at a factor of ∼2-3 higher abundance than in the bulk Earth. For HS2253+8023 the swallowed material was compositionally similar to bulk Earth in being more than 85% by mass in the major element species, O, Mg, Si, and Fe, and with abundances in the distinctive proportions of mineral oxides—compelling evidence for an origin in a rocky parent body. Including previous studies we now know of four heavily polluted white dwarfs where the measured oxygen and hydrogen are consistent with the view that the parents' bodies formed with little ice, interior to any snow line in their nebular environments. The growing handful of polluted white dwarf systems with comprehensive abundance measurements form a baseline for characterizing rocky exoplanet compositions that can be compared with bulk Earth.

  4. Whole-community facilitation regulates biodiversity on Patagonian rocky shores.

    Directory of Open Access Journals (Sweden)

    Brian R Silliman

    Full Text Available Understanding the factors that generate and maintain biodiversity is a central goal in ecology. While positive species interactions (i.e., facilitation have historically been underemphasized in ecological research, they are increasingly recognized as playing important roles in the evolution and maintenance of biodiversity. Dominant habitat-forming species (foundation species buffer environmental conditions and can therefore facilitate myriad associated species. Theory predicts that facilitation will be the dominant community-structuring force under harsh environmental conditions, where organisms depend on shelter for survival and predation is diminished. Wind-swept, arid Patagonian rocky shores are one of the most desiccating intertidal rocky shores ever studied, providing an opportunity to test this theory and elucidate the context-dependency of facilitation.Surveys across 2100 km of southern Argentinean coastline and experimental manipulations both supported theoretical predictions, with 43 out of 46 species in the animal assemblage obligated to living within the matrices of mussels for protection from potentially lethal desiccation stress and predators having no detectable impact on diversity.These results provide the first experimental support of long-standing theoretical predictions and reveal that in extreme climates, maintenance of whole-community diversity can be maintained by positive interactions that ameliorate physical stress. These findings have important conservation implications and emphasize that preserving foundation species should be a priority in remediating the biodiversity consequences of global climate change.

  5. Stabilization of mixed waste - Rocky Flats solar ponds

    International Nuclear Information System (INIS)

    Bittner, T.A.; Mathew, S.A.; Henderson, W.C.

    1993-01-01

    Among the wastes that require disposal as part of the Department of Energy's (DOE's) Environmental Restoration Program are large amounts of contaminated sludge and inorganic wastes. Halliburton NUS Corporation was awarded a contract by EG ampersand G Rocky Flats in March 1991 to stabilize mixed waste sludge contained in five solar evaporator ponds and to reprocess billets of solidified waste called Pondcrete and Saltcrete at DOE's Rocky Flats Plant. The scope of the project consists of waste characterization and treatability studies for process development, followed by design, construction and operation of various process trains to remediate different waste forms ranging from solid Pondcrete/Saltcrete blocks to aqueous brine solutions. One of the significant advances made was the development of a durable and certifiable stabilization formulation capable of treating concentrated nitrate solution wastes. The project uses high-volume grout mixing and pumping technologies with process control techniques that accommodate the heterogeneity of the wastes. To comply with all relevant environmental regulations and to provide a safe working atmosphere for plant personnel, Halliburton NUS designed process trains such that all emissions were eliminated during the remediation process. Personnel protection equipment requirements have been downgraded due to safeguards incorporated in the design. The technical and regulatory issues that were encountered would be typical of stabilization efforts underway at other DOE sites. Thus the lessons learned and concepts developed can be expected to have widespread application

  6. Land disposal restriction (LDR) waste management strategy at Rocky Flats

    International Nuclear Information System (INIS)

    Tyler, R.W.; Anderson, S.A.; Rising, T.L.

    1993-01-01

    The Rocky Flats Plant (RFP) is a government-owned, contractor-operated facility which is a part of the nationwide DOE nuclear weapons production complex. Rocky Flats has accumulated (and will continue to generate) a substantial quantity of mixed waste subject to regulation under the land disposal restrictions (LDR) of the Resource Conservation and Recovery Act (RCRA). These waste streams include low level mixed waste and transuranic mixed waste which are LDR primarily due to solvent and heavy metal contamination. DOE and EPA have entered into a Federal Facility Compliance Agreement (FFCA) which requires actions to be taken to ensure the accurate identification, safe storage and minimization of LDR mixed wastes prior to their ultimate treatment and/or disposal. As required by the FFCA, DOE has prepared a Comprehensive Treatment and Management Plant (CTMP) which describes the strategy and commitments for bringing LDR wastes at RFP into compliance with applicable regulations. This strategy includes waste characterization and reclassification, utilization of existing commercial and DOE treatment capacity, as well as, the development and implementation of treatment systems (and other management systems) for the purpose of achieving LDR regulatory compliance and ultimate waste disposal. This paper will give an overview of this strategy including a description of the major waste streams being addressed, the regulatory drivers, and plans and status of ongoing treatment systems technology development and implementation efforts

  7. Adult Onset Still's Disease and Rocky Mountain Spotted Fever

    Directory of Open Access Journals (Sweden)

    Paul Persad

    2010-01-01

    Full Text Available Adult Still's Disease was first described in 1971 by Bywaters in fourteen adult female patients who presented with symptoms indistinguishable from that of classic childhood Still's Disease (Bywaters, 1971. George Still in 1896 first recognized this triad of quotidian (daily fevers, evanescent rash, and arthritis in children with what later became known as juvenile inflammatory arthritis (Still, 1990. Adult Onset Still's Disease (AOSD is an inflammatory condition of unknown etiology characterized by an evanescent rash, quotidian fevers, and arthralgias. Numerous infectious agents have been associated with its presentation. This case is to our knowledge the first presentation of AOSD in the setting of Rocky Mountain Spotted Fever. Although numerous infectious agents have been suggested, the etiology of this disorder remains elusive. Nevertheless, infection may in fact play a role in triggering the onset of symptoms in those with this disorder. Our case presentation is, to our knowledge, the first case of Adult Onset Still's Disease associated with Rocky Mountain spotted fever (RMSF.

  8. Validation of KENO-based criticality calculations at Rocky Flats

    International Nuclear Information System (INIS)

    Felsher, P.D.; McKamy, J.N.; Monahan, S.P.

    1992-01-01

    In the absence of experimental data, it is necessary to rely on computer-based computational methods in evaluating the criticality condition of a nuclear system. The validity of the computer codes is established in a two-part procedure as outlined in ANSI/ANS 8.1. The first step, usually the responsibility of the code developer, involves verification that the algorithmic structure of the code is performing the intended mathematical operations correctly. The second step involves an assessment of the code's ability to realistically portray the governing physical processes in question. This is accomplished by determining the code's bias, or systematic error, through a comparison of computational results to accepted values obtained experimentally. In this paper, the authors discuss the validation process for KENO and the Hansen-Roach cross sections in use at EG and G Rocky Flats. The validation process at Rocky Flats consists of both global and local techniques. The global validation resulted in a maximum k eff limit of 0.95 for the limiting-accident scanarios of a criticality evaluation

  9. Circumscribing campo rupestre – megadiverse Brazilian rocky montane savanas

    Directory of Open Access Journals (Sweden)

    RJV. Alves

    Full Text Available Currently campo rupestre (CR is a name accepted and used internationally by botanists, zoologists, and other naturalists, usually applied to a very specific ecosystem, despite the lack of a consensual published circumscription. We present a tentative geographic circumscription of the term, combining data on climate, geology, geomorphology, soil, flora, fauna and vegetation. The circumscription of campo rupestre proposed herein is based on the following premises: (1 the classification of vegetation is not an exact science, and it is difficult to attain a high degree of consensus to the circumscription of vegetation names; (2 despite this, vegetation classification is useful for conservation and management. It is thus desirable to circumscribe vegetation types with the greatest attainable precision; (3 there is a need to preserve all montane and rocky vegetation types, regardless of classification, biome, etc; (4 the CRs are formed by a complex mosaic of vegetation types including rock-dwelling, psammophilous, aquatic, epiphytic, and penumbral plant communities. Campos rupestres stricto sensu are a Neotropical, azonal vegetation complex endemic to Brazil, forming a mosaic of rocky mountaintop “archipelagos” inserted within a matrix of zonal vegetation, mainly in the Cerrado and Caatinga provinces of the Brazilian Shield (southeastern, northeastern and central-western regions, occurring mainly above 900 m asl. up to altitudes exceeding 2000 m, having measured annual precipitation between 800 and 1500 mm, and an arid season of two to five months.

  10. Circumscribing campo rupestre - megadiverse Brazilian rocky montane savanas.

    Science.gov (United States)

    Alves, R J V; Silva, N G; Oliveira, J A; Medeiros, D

    2014-05-01

    Currently campo rupestre (CR) is a name accepted and used internationally by botanists, zoologists, and other naturalists, usually applied to a very specific ecosystem, despite the lack of a consensual published circumscription. We present a tentative geographic circumscription of the term, combining data on climate, geology, geomorphology, soil, flora, fauna and vegetation. The circumscription of campo rupestre proposed herein is based on the following premises: (1) the classification of vegetation is not an exact science, and it is difficult to attain a high degree of consensus to the circumscription of vegetation names; (2) despite this, vegetation classification is useful for conservation and management. It is thus desirable to circumscribe vegetation types with the greatest attainable precision; (3) there is a need to preserve all montane and rocky vegetation types, regardless of classification, biome, etc; (4) the CRs are formed by a complex mosaic of vegetation types including rock-dwelling, psammophilous, aquatic, epiphytic, and penumbral plant communities. Campos rupestres stricto sensu are a Neotropical, azonal vegetation complex endemic to Brazil, forming a mosaic of rocky mountaintop "archipelagos" inserted within a matrix of zonal vegetation, mainly in the Cerrado and Caatinga provinces of the Brazilian Shield (southeastern, northeastern and central-western regions), occurring mainly above 900 m asl. up to altitudes exceeding 2000 m, having measured annual precipitation between 800 and 1500 mm, and an arid season of two to five months.

  11. Conference summaries. Canadian Nuclear Association 29. annual conference; Canadian Nuclear Society 10. annual conference

    International Nuclear Information System (INIS)

    1989-01-01

    Separate abstracts were prepared for 15 papers from the twenty-ninth Annual Conference of the Canadian Nuclear Association. Abstracts were also prepared for the 102 papers from the tenth Annual Conference of the Canadian Nuclear Society

  12. Conference summaries. Canadian Nuclear Association 29. annual conference; Canadian Nuclear Society 10. annual conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-12-31

    Separate abstracts were prepared for 15 papers from the twenty-ninth Annual Conference of the Canadian Nuclear Association. Abstracts were also prepared for the 102 papers from the tenth Annual Conference of the Canadian Nuclear Society.

  13. Glacier Mass Changes of Lake-Terminating Grey and Tyndall Glaciers at the Southern Patagonia Icefield Derived From Geodetic Observations and Energy and Mass Balance Modeling

    Directory of Open Access Journals (Sweden)

    Stephanie S. Weidemann

    2018-06-01

    Full Text Available In this study we demonstrate how energy and mass fluxes vary in space and time for Grey and Tyndall glaciers at the Southern Patagonia Icefield (SPI. Despite the overall glacier retreat of most Patagonian glaciers, a recent increase in mass loss has been observed, but individual glaciers respond differently in terms of spatial and temporal changes. In this context, the detailed investigation of the effect of mass balance processes on recent glacier response to climate forcing still needs refinement. We therefore quantify surface energy-fluxes and climatic mass balance of the two neighboring glaciers, Grey and Tyndall. The COupled Snow and Ice energy and MAss balance model COSIMA is applied to assess recent surface energy and climatic mass balance variability with a high temporal and spatial resolution for a 16-year period between April 2000 and March 2016. The model is driven by downscaled 6-hourly atmospheric data derived from ERA-Interim reanalysis and MODIS/Terra Snow Cover and validated against ablation measurements made in single years. High resolution precipitation fields are determined by using an analytical orographic precipitation model. Frontal ablation is estimated as residual of climatic mass balance and geodetic mass balance derived from TanDEM-X/SRTM between 2000 and 2014. We simulate a positive glacier-wide mean annual climatic mass balance of +1.02 ± 0.52 m w.e. a−1 for Grey Glacier and of +0.68 ± 0.54 m w.e. a−1 for Tyndall Glacier between 2000 and 2014. Climatic mass balance results show a high year to year variability. Comparing climatic mass balance results with previous studies underlines the high uncertainty in climatic mass balance modeling with respect to accumulation on the SPI. Due to the lack of observations accumulation estimates differ from previous studies based on the methodological approaches. Mean annual ice loss by frontal ablation is estimated to be 2.07 ± 0.70 m w.e. a−1 for Grey Glacier and 3.26 ± 0

  14. Rock glaciers Gruben, Muragl and Murtel, Switzerland: Area-wide flow fields, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — Besides their thermal and mechanical properties, rock glaciers are essentially defined by their kinematics. Knowledge of the permafrost flow field provides important...

  15. Optical Remote Sensing of Glacier Characteristics: A Review with Focus on the Himalaya

    Science.gov (United States)

    Racoviteanu, Adina E.; Williams, Mark W.; Barry, Roger G.

    2008-01-01

    The increased availability of remote sensing platforms with appropriate spatial and temporal resolution, global coverage and low financial costs allows for fast, semi-automated, and cost-effective estimates of changes in glacier parameters over large areas. Remote sensing approaches allow for regular monitoring of the properties of alpine glaciers such as ice extent, terminus position, volume and surface elevation, from which glacier mass balance can be inferred. Such methods are particularly useful in remote areas with limited field-based glaciological measurements. This paper reviews advances in the use of visible and infrared remote sensing combined with field methods for estimating glacier parameters, with emphasis on volume/area changes and glacier mass balance. The focus is on the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor and its applicability for monitoring Himalayan glaciers. The methods reviewed are: volumetric changes inferred from digital elevation models (DEMs), glacier delineation algorithms from multi-spectral analysis, changes in glacier area at decadal time scales, and AAR/ELA methods used to calculate yearly mass balances. The current limitations and on-going challenges in using remote sensing for mapping characteristics of mountain glaciers also discussed, specifically in the context of the Himalaya. PMID:27879883

  16. Water, Ice, and Meteorological Measurements at South Cascade Glacier, Washington, Balance Years 2004 and 2005

    Science.gov (United States)

    Bidlake, William R.; Josberger, Edward G.; Savoca, Mark E.

    2007-01-01

    Winter snow accumulation and summer snow and ice ablation were measured at South Cascade Glacier, Washington, to estimate glacier mass-balance quantities for balance years 2004 and 2005. The North Cascade Range in the vicinity of South Cascade Glacier accumulated smaller than normal winter snowpacks during water years 2004 and 2005. Correspondingly, the balance years 2004 and 2005 maximum winter snow balances of South Cascade Glacier, 2.08 and 1.97 meters water equivalent, respectively, were smaller than the average of such balances since 1959. The 2004 glacier summer balance (-3.73 meters water equivalent) was the eleventh most negative during 1959 to 2005 and the 2005 glacier summer balance (-4.42 meters water equivalent) was the third most negative. The relatively small winter snow balances and unusually negative summer balances of 2004 and 2005 led to an overall loss of glacier mass. The 2004 and 2005 glacier net balances, -1.65 and -2.45 meters water equivalent, respectively, were the seventh and second most negative during 1953 to 2005. For both balance years, the accumulation area ratio was less than 0.05 and the equilibrium line altitude was higher than the glacier. The unusually negative 2004 and 2005 glacier net balances, combined with a negative balance previously reported for 2003, resulted in a cumulative 3-year net balance of -6.20 meters water equivalent. No equal or greater 3-year mass loss has occurred previously during the more than 4 decades of U.S. Geological Survey mass-balance measurements at South Cascade Glacier. Accompanying the glacier mass losses were retreat of the terminus and reduction of total glacier area. The terminus retreated at a rate of about 17 meters per year during balance year 2004 and 15 meters per year during balance year 2005. Glacier area near the end of balance years 2004 and 2005 was 1.82 and 1.75 square kilometers, respectively. Runoff from the basin containing the glacier and from an adjacent nonglacierized basin was

  17. Glacier beds that will be exposed in the future: How will geomorphologic and hydrologic processes develop?

    Science.gov (United States)

    Linsbauer, Andreas; Paul, Frank; Haeberli, Wilfried

    2014-05-01

    The rapid shrinkage of glaciers in the Alps has widespread impacts on relief development and hydrology. Slope failures, collapse of lateral moraines, loose debris in glacier fore-fields, new lakes and changing river beds are among the most visible impacts. They already require increased attention by tourists, monitoring by local authorities and mitigation measures (e.g. www.gletschersee.ch). A view into potential future developments (after glaciers have disappeared) is thus of high interest. With recently developed models that reconstruct glacier bed topography from easily available datasets (e.g. glacier outlines and a DEM) over entire mountain ranges, potential developments of the landscape and hydrology can be quantitatively determined. The modelled glacier beds - though they must be seen as a rough first order approximation only - also allows the investigation of a wide range of glaciological relations and dependencies that have been widely applied but were never investigated for a large sample of glaciers so far. A key reason is that information on glacier thickness distribution and total ice volume is sparse and that the future development of glaciers can only be modelled realistically when a glacier bed is available. Hence, with the glacier beds now available there is a larger number of geomorphological, glaciological and hydrological studies ahead of us. This presentation is providing an overview on the lessons learned about glaciers and their future development from the modelled glacier beds, the expected changes in hydrology (e.g. decreasing glacier volume and formation of new lakes) and potential impacts from the altered geomorphology (e.g. debuttressing of rock walls). In particular the flat tongues of larger valley glaciers are rather thick and leave oversteepened lateral moraines or rock walls behind, towering above overdeepenings in the glacier bed that might be filled with water. It is thus expected that the hazard potential will further increase in

  18. Studies of Bagley Icefield during surge and Black Rapids Glacier, Alaska, using spaceborne SAR interferometry

    Science.gov (United States)

    Fatland, Dennis Robert

    1998-12-01

    This thesis presents studies of two temperate valley glaciers---Bering Glacier in the Chugach-St.Elias Mountains, South Central Alaska, and Black Rapids Glacier in the Alaska Range, Interior Alaska---using differential spaceborne radar interferometry. The first study was centered on the 1993--95 surge of Bering Glacier and the resultant ice dynamics on its accumulation area, the Bagley Icefield. The second study site was chosen for purposes of comparison of the interferometry results with conventional field measurements, particularly camera survey data and airborne laser altimetry. A comprehensive suite of software was written to interferometrically process synthetic aperture radar (SAR) data in order to derive estimates of surface elevation and surface velocity on these subject glaciers. In addition to these results, the data revealed unexpected but fairly common concentric rings called 'phase bull's-eyes', image features typically 0.5 to 4 km in diameter located over the central part of various glaciers. These bull's-eyes led to a hypothetical model in which they were interpreted to indicate transitory instances of high subglacial water pressure that locally lift the glacier from its bed by several centimeters. This model is associated with previous findings about the nature of glacier bed hydrology and glacier surging. In addition to the dynamical analysis presented herein, this work is submitted as a contribution to the ongoing development of spaceborne radar interferometry as a glaciological tool.

  19. The new Inventory of Italian Glaciers: Present knowledge, applied methods and preliminary results

    Science.gov (United States)

    Smiraglia, Claudio; Diolaiuti, Guglielmina; D'Agata, Carlo; Maragno, Davide; Baroni, Carlo; Mortara, Gianni; Perotti, Luigi; Bondesan, Aldino; Salvatore, Cristina; Vagliasindi, Marco; Vuillermoz, Elisa

    2013-04-01

    A new Glacier Inventory is an indispensable requirement in Italy due to the importance of evaluating the present glacier coverage and the recent changes driven by climate. Furthermore Alpine glaciers represent a not negligible water and touristic resource then to manage and promote them is needed to know their distribution, size and features. The first Italian Glacier Inventory dates back to 1959-1962. It was compiled by the Italian Glaciological Committee (CGI) in cooperation with the National Research Council (CNR); this first inventory was mainly based on field data coupled with photographs (acquired on the field) and high resolution maps. The Italian glaciation resulted to be spread into 754 ice bodies which altogether were covering 525 km2. Moreover in the Eighties a new inventory was compiled to insert Italian data into the World Glacier Inventory (WGI); aerial photos taken at the end of the Seventies (and in some cases affected by a high and not negligible snow coverage) were used as the main source of data. No other national inventory were compiled after that period. Nevertheless during the last decade the largest part of the Italian Alpine regions have produced regional and local glacier inventories which in several cases are also available and queried through web sites and web GIS application. The actual need is now to obtain a complete, homogeneous and contemporary picture of the Italian Glaciation which encompasses the already available regional and local data and all the new updated information coming from new sources of data (e.g.: orthophotos, satellite imagines, etc..). The challenge was accepted by the University of Milan, the EvK2CNR Committee and the Italian Glaciological Committee who, with the sponsorship of Levissima Spa, are presently working to compile the new updated Italian Glacier Inventory. The first project step is to produce a unique homogeneous glacier database including glacier boundary and surface area and the main fundamental

  20. Mechanism of the 2016 giant twin glacier collapse in Aru range, Tibet

    Science.gov (United States)

    Gilbert, A.; Leinss, S.; Kääb, A.; Kargel, J. S.; Yao, T.; Gascoin, S.; Leonard, G. J.; Berthier, E.; Karki, A.

    2017-12-01

    In northwestern Tibet (34.0°N, 82.2°E) near lake Aru Co, the entire ablation area of two unnamed glaciers (Aru-1 and Aru-2) suddenly collapsed on 17 July 2016 and 21 September 2016 and transformed into a mass flow that ran out over a distance of over several km, killing nine people. These two events are unique and defined a new kind of glacier behavior almost never observed before. The only similar event currently documented is the 2002 Kolka Glacier mass flow (Caucasus Mountains). Using remote sensing observations and 3D thermo-mechanical modeling of the two glaciers, we reconstructed glacier thermal regime, thickness, basal friction evolution and ice damaging state prior to the collapse. We show that frictional change leading to the collapse occurred in the temperate areas of a polythermal structure that is likely close to equilibrium with the local climate. The collapses were driven by a fast and sustained friction change in the temperate part of the glacier for which the glacier shape was not able to adjust due to the cold-based parts providing strong resisting force to sliding. This led to high stresses on the cold margins of the glacier where ice deformation became partially accommodated by fracturing until the final collapse occurred. Field investigations reveal that those two glaciers are flowing on a soft and fine-grained sedimentary lithology prone to landslide activity in the presence of water. This suggests that fast friction change in the temperate part of the glacier is linked to shear strength weakening in the sediment and till underneath the glacier in response to increasing water pore pressure at the glacier base. The Kolka Glacier mass flow also occurred on pyroclastic rocks well known for their landslide activities. This suggests that the three gigantic glacier collapses documented to date involve specific bedrock lithology where failure is driven by shear strength weakening in the glacier till in a landslide-like process. Contrary to a