WorldWideScience

Sample records for analysis north america

  1. Industry analysis certification organisations in North America

    OpenAIRE

    Kulsky, William

    2006-01-01

    Manufacturers of electrical devices in North America have traditionally been regulatory bound to demonstrate that their products comply with all applicable national standards prior to distribution or use. The means and methods available to do so have substantially changed in the last two decades. The purpose of this paper is to analyze the approach the certification industry has adopted to accommodate change and to evaluate its ability to evolve and meet foreseeable trends. The analysis will ...

  2. Analysis of the Remote Access Market in North America

    OpenAIRE

    Björk, Mikael; Blanc, Dominique

    2012-01-01

    How can a small European technology company make it to the giant North American market? This thesis deals with how a new entrant with disruptive technologies and products in the remote access automation market could enter and develop a business in North America where this market barely exists. To address this problem, we have analyzed if the Porter Five Force framework together with the Blue Ocean concept is a viable approach to evaluate a company’s competitive edge, and what strategy to appl...

  3. 75 FR 17407 - Service Corporation International and Keystone North America Inc.; Analysis of Agreement...

    Science.gov (United States)

    2010-04-06

    ... Service Corporation International and Keystone North America Inc.; Analysis of Agreement Containing... any sensitive personal information, such as an individual's Social Security Number; date of birth... sensitive health information, such as medical records or other individually identifiable health...

  4. A Market Analysis for PVD Coating System of Aurora North America

    OpenAIRE

    Chen, Wen-Hao Arthur

    2012-01-01

    Aurora North America, a venture founded by Dr. Da-Yung Wang, endeavours to offer its coating products while providing low-cost, quality solutions to North American manufacturers who apply thin-films to their goods. The objective of this proposed research is to provide a comprehensive analysis of the market opportunities for Aurora. This paper seeks to identify markets that have yet to fully adopt Physical Vapor Deposition (PVD) technology, as well as their potential customers. Market trend of...

  5. Analysis of Long-Term Precipitation Sequencing Pattern Changes in North America

    Science.gov (United States)

    Roque, S.; Kumar, P.

    2015-12-01

    This study evaluates changes in long-term precipitation patterns in North America, focusing specifically on precipitation sequencing. Previous precipitation studies have explored changes in extreme precipitation events, intensity, and distribution, but sequencing changes and their effects are still largely not understood. Precipitation sequencing, or the overall temporal pattern of precipitation events, is a vital yet often overlooked part of developing long-term climate predictions; the assumption of long-term stationarity in climate variability, which suggests that past observed temporal patterns are likely to continue and can therefore be projected, weakens the robustness of climate models. Additionally, changes in sequencing could be a driver for fluctuations in the highly interconnected hydrologic cycle, meaning that tipping points and critical changes in the cycle could be better anticipated given a more complete picture of long-term temporal patterns. Analysis was based on precipitation data collected by the National Climatic Data Center for approximately 9000 stations in North America. Temporal patterns recorded at each station - the sequence of consecutive days with or without rain and the lengths of those increments - were reviewed and compared on a decadal and seasonal scale. Comparisons to date indicate that long-term precipitation patterns are non-stationary and therefore cannot be relied upon for long-term climate projections. It remains to be seen how exactly regional temporal patterns have fluctuated over time in North America, and results could provide interesting insight into observed hydrologic changes or serve to reinforce existing theories regarding regional hydrologic studies.

  6. Anaglyph, North America

    Science.gov (United States)

    2003-01-01

    This anaglyph (stereoscopic view) of North America was generated with data from the Shuttle Radar Topography Mission (SRTM). It is best viewed at or near full resolution with anaglyph glasses. For this broad view the resolution of the data was first reduced to 30 arcseconds (about 928 meters north-south and 736 meters east-west in central North America), matching the best previously existing global digital topographic data set called GTOPO30. The data were then resampled to a Mercator projection with approximately square pixels (about one kilometer, or 0.6 miles, on each side). Even at this decreased resolution the variety of landforms comprising the North American continent is readily apparent.Active tectonics (structural deformation of the Earth's crust) along and near the Pacific North American plate boundary creates the great topographic relief seen along the Pacific coast. Earth's crustal plates converge in southern Mexico and in the northwest United States, melting the crust and producing volcanic cones. Along the California coast, the plates are sliding laterally past each other, producing a pattern of slices within the San Andreas fault system. And, where the plates are diverging, the crust appears torn apart as one huge tear along the Gulf of California (northwest Mexico), and as the several fractures comprising the Basin and Range province (in and around Nevada).Across the Great Plains, erosional patterns dominate, with stream channels surrounding and penetrating the remnants of older smooth slopes east of the Rocky Mountains. This same erosion process is exposing the bedrock structural patterns of the Black Hills in South Dakota and the Ozark Mountains in Arkansas. Lateral erosion and sediment deposition by the Mississippi River has produced the flatlands of the lower Mississippi Valley and the Mississippi Delta.To the north, evidence of the glaciers of the last ice age is widely found, particularly east of the Canadian Rocky Mountains and around the

  7. Mosques in North America

    Directory of Open Access Journals (Sweden)

    Omar Khalidi

    2008-12-01

    Full Text Available The following article derived from an exhibit catalogue put together by Public Affairs Germany in the U.S. Embassy in Berlin and the U.S. Consulates in Frankfurt and Düsseldorf and accompanied Dr. Omar Khalidi’s photo exhibit “Mosques in America.” There are over 2,000 mosques in the United States, mostly housed in buildings originally built for other purposes. American mosques built in the last few decades, however, in the period in which Islam has begun to feel at home in the United States, are almost universally architect-designed.

  8. Full-Genome Analysis of Avian Influenza A(H5N1) Virus from a Human, North America, 2013

    OpenAIRE

    Pabbaraju, Kanti; Tellier, Raymond; Wong, Sallene; Li, Yan; Bastien, Nathalie; Tang, Julian W.; Drews, Steven J.; Jang, Yunho; Davis, C. Todd; Fonseca, Kevin; Tipples, Graham A

    2014-01-01

    Full-genome analysis was conducted on the first isolate of a highly pathogenic avian influenza A(H5N1) virus from a human in North America. The virus has a hemagglutinin gene of clade 2.3.2.1c and is a reassortant with an H9N2 subtype lineage polymerase basic 2 gene. No mutations conferring resistance to adamantanes or neuraminidase inhibitors were found.

  9. The Inland Penetration of Atmospheric Rivers over Western North America: A Lagrangian Analysis

    Science.gov (United States)

    Rutz, J. J.; Steenburgh, W. J.; Ralph, F. M.

    2014-12-01

    Although atmospheric rivers (ARs) typically weaken following landfall, those that penetrate inland can contribute to heavy precipitation and high-impact weather within the interior of western North America. In this paper, we examine the evolution of ARs over western North America using trajectories released at 950 and 700 hPa within cool-season ARs along the Pacific coast. These trajectories are classified as coastal decaying, inland penetrating, or interior penetrating based on whether they remain within an AR upon reaching selected transects over western North America. Interior-penetrating AR trajectories most frequently make landfall along the Oregon coast, but the greatest fraction of landfalling AR trajectories that eventually penetrate into the interior is found along the Baja Peninsula. In contrast, interior-penetrating trajectories rarely traverse the southern "high" Sierra. At landfall, interior-penetrating trajectories are associated with a more amplified flow pattern, more southwesterly (vs. westerly) flow along the Pacific coast, and larger water vapor transport (qu). The larger initial qu of interior-penetrating trajectories is due primarily to larger initial water vapor (q) and wind speed (u) for those initiated at 950 and 700 hPa, respectively. Inland- and interior-penetrating AR trajectories maintain large qu over the interior due partially to increases in u that offset decreases in q, particularly in the vicinity of topographical barriers. Therefore, synoptic conditions and trajectory pathways favoring larger initial qu at the coast, limited water vapor depletion by orographic precipitation, and increases in u over the interior are keys to differentiating interior-penetrating from coastal-decaying AR trajectories.

  10. Smoke injection heights from fires in North America: analysis of 5 years of satellite observations

    Directory of Open Access Journals (Sweden)

    M. Val Martin

    2009-09-01

    Full Text Available We analyze a multi-year record of aerosol smoke plume heights derived from observations over North America made by the Multi-angle Imaging SpectroRadiometer (MISR instrument on board the NASA Earth Observing System Terra satellite. We characterize the magnitude and variability of smoke plume heights for various biomes, and assess the contribution of local atmospheric and fire conditions to this variability. Plume heights are highly variable, ranging from a few hundred meters up to 5000 m above the terrain at the Terra overpass time (11:00–14:00 local time. The largest plumes are found over the boreal region (median values of ∼850 m height, 24 km length and 940 m thickness, whereas the smallest plumes are found over cropland and grassland fires in the contiguous US (median values of ∼530 m height, 12 km length and 550–640 m thickness. The analysis of plume heights in combination with assimilated meteorological observations from the NASA Goddard Earth Observing System indicates that a significant fraction (4–12% of plumes from fires are injected above the boundary layer (BL, consistent with earlier results for Alaska and the Yukon Territories during summer 2004. Most of the plumes located above the BL (>83% are trapped within stable atmospheric layers. We find a correlation between plume height and the MODerate resolution Imaging Spectroradiometer (MODIS fire radiative power (FRP thermal anomalies associated with each plume. Smoke plumes located in the free troposphere (FT exhibit larger FRP values (1620–1640 MW than those remaining within the BL (174–465 MW. Plumes located in the FT without a stable layer reach higher altitudes and are more spread-out vertically than those associated with distinct stable layers (2490 m height and 2790 m thickness versus 1880 m height and 1800 thickness. The MISR plume climatology exhibits a well-defined seasonal cycle of plume heights in boreal and temperate biomes, with greater heights during June

  11. Ammonia and hydrogen sulfide emissions from swine production facilities in North America: a meta-analysis.

    Science.gov (United States)

    Liu, Z; Powers, W; Murphy, J; Maghirang, R

    2014-04-01

    Literature on NH3 and H2S emissions from swine production facilities in North America was reviewed, and a meta-analysis was conducted on measured emissions data from swine houses and manure storage facilities as well as concentration data in the vicinity of swine production facilities. Results from more than 80 studies were compiled with results from the 11 swine sites in the National Air Emissions Monitoring Study (NAEMS). Data across studies were analyzed statistically using the MIXED procedures of SAS. The median emission rates from swine houses across various production stages and manure handling systems were 2.78 and 0.09 kg/yr per pig for NH3 and H2S, respectively. The median emission rates from swine storage facilities were 2.08 and 0.20 kg/yr per pig for NH3 and H2S, respectively. The size of swine farm that may trigger the need to report NH3 emissions under the Emergency Planning and Community Right-to-Know Act (EPCRA) is 3,410 pigs on the basis of the median NH3 emission rate (4.86 kg/yr per pig), but the threshold can be as low as 992 pigs on the basis of the 90th-percentile emission rates (16.71 kg/yr per pig). Swine hoop houses had significantly higher NH3 emission rate (14.80 kg/yr per pig) than other manure-handling systems (P pig, P = 0.03). Farrowing houses had the highest H2S emission rate (2.50 kg/yr per pig), followed by gestation houses, and finishing houses had the lowest H2S emission rate (P < 0.01). Regression models for NH3 and H2S emission rates were developed for finishing houses with deep pits, recharge pits, and lagoons. The NH3 emission rates increased with increasing air temperature, but effects of air temperature on H2S emission rates were not significant. The recharge interval of manure pits significantly affected H2S but not NH3 emission rates. The H2S emission rates were also influenced by the size of the operation. Although NH3 and H2S concentrations at the edge of swine houses or lagoons were often higher than corresponding

  12. A Comparative Analysis of Primary and Extreme Characteristics of Dry or Wet Status between Asia and North America

    Institute of Scientific and Technical Information of China (English)

    HUA Lijuan; MA Zhuguo; ZHONG Linhao

    2011-01-01

    In this study, the Palmer Drought Severity Index (PDSI) was used to analyze the average and extreme dry/wet states of Asia and North America from 1953 to 2003. The results indicate that the two continents underwent drying trends during this period. Compared with North America, Asia showed more severe drought trends. However, more significant and regular seasonal variation for drought was found in North America. The driest regions in Asia were located in the northern region of China, Mongolia, and eastern mid-Siberian plateau. Most regions in central North America were relatively wetter than other regions.The northern and southwestern regions of North America, as well as the Atlantic and Pacific coastal areas,experienced the most drought during this period. A sharp increase of the drought area and the number of extreme drought events took place from 1997 to 2003 in both Asia and North America. Severe drought events were more likely to occur during the summer on both continents. Asia had the most extreme drought events during July, but North America reached its highest drought frequency from June to September. In Asia, a persistent increasing trend of extreme drought emerged throughout the studied period. However,a more complex evolution of drought emerged in North America: a decreasing trend appeared before the mid-1960s and an increasing trend appeared after the late 1970s. A relatively steady dry/wet status was observed between the mid-1960s and the late 1970s. The role of exceptional, extreme drought events with respect to the La Nifia event was considered during 1997-2003.

  13. Developments in Impact Assessment in North America

    Science.gov (United States)

    Beginning with a background of recent global developments in this area, this presentation will focus on how global research has impacted North America and how North America is providing additional developments to address the issues of the global economy. Recent developments inc...

  14. Health outcomes among HIV-positive Latinos initiating antiretroviral therapy in North America versus Central and South America

    OpenAIRE

    Carina Cesar; Koethe, John R; Mark J Giganti; Peter Rebeiro; Althoff, Keri N; Sonia Napravnik; Angel Mayor; Beatriz Grinsztejn; Marcelo Wolff; Denis Padgett; Juan Sierra-Madero; Eduardo Gotuzzo; Sterling, Timothy R; James Willig; Julie Levison

    2016-01-01

    Introduction: Latinos living with HIV in the Americas share a common ethnic and cultural heritage. In North America, Latinos have a relatively high rate of new HIV infections but lower rates of engagement at all stages of the care continuum, whereas in Latin America antiretroviral therapy (ART) services continue to expand to meet treatment needs. In this analysis, we compare HIV treatment outcomes between Latinos receiving ART in North America versus Latin America. Methods: HIV-positive adult...

  15. North America and South America (NA-SA) neuropathy project.

    Science.gov (United States)

    Pasnoor, Mamatha; Nascimento, Osvaldo J M; Trivedi, Jaya; Wolfe, Gil I; Nations, Sharon; Herbelin, Laura; de Freitas, M G; Quintanilha, Giseli; Khan, Saud; Dimachkie, Mazen; Barohn, Richard

    2013-08-01

    Peripheral neuropathy is a common neurological disorder. There may be important differences and similarities in the diagnosis of peripheral neuropathy between North America (NA) and South America (SA). Neuromuscular databases were searched for neuropathy diagnosis at two North American sites, University of Kansas Medical Center and University of Texas Southwestern Medical Center, and one South American site, Federal Fluminense University in Brazil. All patients were included into one of the six major categories: immune-mediated, diabetic, hereditary, infectious/inflammatory, systemic/metabolic/toxic (not diabetic) and cryptogenic. A comparison of the number of patients in each category was made between North America and South America databases. Total number of cases in North America was 1090 and in South America was 1034 [immune-mediated: NA 215 (19.7%), SA 191 (18%); diabetic: NA 148 (13.5%), SA 236 (23%); hereditary: NA 292 (26.7%), SA 103 (10%); infectious/inflammatory: NA 53 (4.8%), SA 141 (14%); systemic/metabolic/toxic: NA 71 (6.5%), SA 124 (12%); cryptogenic: NA 311 (28.5%), SA 239 (23%)]. Some specific neuropathy comparisons were hereditary neuropathies [Charcot-Marie-Tooth (CMT) cases] in NA 246/292 (84.2%) and SA 60/103 (58%); familial amyloid neuropathy in SA 31/103 (30%) and none in NA. Among infectious neuropathies, cases of human T-lymphotropic virus type 1 (HTLV-1) neuropathy in SA were 36/141(25%), Chagas disease in SA were 13/141(9%) and none for either in NA; cases of neuropathy due to leprosy in NA were 26/53 (49%) and in SA were 39/141(28%). South American tertiary care centers are more likely to see patients with infectious, diabetic and hereditary disorders such as familial amyloid neuropathies. North American tertiary centers are more likely to see patients with CMT. Immune neuropathies and cryptogenic neuropathies were seen equally in North America and South America.

  16. Bathymetry of North America - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Bathymetry of North America map layer shows depth ranges using colors. The image was derived from the National Geophysical Data Center?s ETOPO2 elevation data,...

  17. Nighttime Lights of North America - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is an image of nighttime lights for North America, including the Caribbean and most of Mexico. The data were collected in 1996 and 1997 as part of...

  18. Molecular Analysis of an Allozyme Cline: Alcohol Dehydrogenase in Drosophila Melanogaster on the East Coast of North America

    OpenAIRE

    Berry, A.; Kreitman, M

    1993-01-01

    Clines may either be selectively maintained or be the by-product of nonadaptive processes related to population structure and history. Drosophila melanogaster populations on the east coast of North America show a latitudinal cline in the frequencies of two common electrophoretically distinguishable alleles at the alcohol dehydrogenase locus (Adh), designated Adh-S and Adh-F. This cline may either be adaptive or an artifact of a possible recent dual founding of North American D. melanogaster p...

  19. Adult Education Faculty and Programs in North America

    Science.gov (United States)

    Tisdell, Elizabeth J.; Wright, Robin Redmon; Taylor, Edward W.

    2016-01-01

    This article reports on the findings of a quantitative survey of North American adult education faculty and a textual analysis of websites of adult education graduate programs in North America conducted in the fall of 2013. This study examined background information about adult education faculty and programs; the nature of faculty work interests,…

  20. Forest Health Status in North America

    Directory of Open Access Journals (Sweden)

    Borys Tkacz

    2007-01-01

    Full Text Available The forests of North America provide a variety of benefits including water, recreation, wildlife habitat, timber, and other forest products. However, they continue to face many biotic and abiotic stressors including fires, native and invasive pests, fragmentation, and air pollution. Forest health specialists have been monitoring the health of forests for many years. This paper highlights some of the most damaging forest stressors affecting North American forests in recent years and provides some projections of future risks.

  1. Social support and anomie: a multilevel analysis of anomie in Europe and North America.

    Science.gov (United States)

    Liqun Cao; Ruohui Zhao; Ling Ren; Zhao, Jihong Solomon

    2010-08-01

    On the basis of the reasoning of social support theory, the authors examine the macro effect of social support on anomie at the individual level. Data from international surveys have documented wide variation in anomie across nations, but to what extent this variation among nations can be contributed to structural characteristics has not been explored before. Using hierarchical linear modeling techniques to sort out the effects of structural context and personal characteristics on anomie across 31 European and North American nations, the authors test the hypothesis that variation in social support at the national level is inversely related to individuals' sense of anomie. The study results support the hypothesis that structural characteristics of a nation, such as social support and population growth, influence individuals' sense of anomie. At the individual level, the results are consistent with Merton's predictions about anomie and the reasoning of social support theory. Policy implication is discussed within the limitations of data.

  2. Chinese Studies Librarianship in North America

    Institute of Scientific and Technical Information of China (English)

    Karen T. Wei

    2004-01-01

    Although American libraries had begun collecting Chinese language materials in the 19th century, notably the United States Library of Congress in 1869, Yale in 1878, Harvard in 1879, and Berkeley in 1896, East Asian studies librarianship in North America, including China studies librarianship, was not fully developed until the 1960s. There was no formal organization that represented the interest of Chinese studies librarians because there were few of them and most of them were China scholars rather than trained librarians. More than 100 years later, the number of Chinese studies librarians in North America has increased considerably,primarily in response to the demand in the field of China studies and more recently to the needs of immigrant population and the general public who has an interest in China.This paper traces the history and growth of Chinese studies librarianship in North America, documents the development of the professional organization that represents Chinese studies librarians, and examines the training programs that prepare them for their jobs. It also attempts to propose an international exchange forum aiming to bring together Chinese studies librarians in North America and librarians in China in sharing their experience and expertise to achieve the ultimate goal of serving the users.

  3. Rat Lungworm Expands into North America

    Centers for Disease Control (CDC) Podcasts

    2016-01-21

    Emily York, integrated pest management specialist at the Sam Noble Museum of Natural History, discusses the rat lungworm expansion in North America.  Created: 1/21/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 1/21/2016.

  4. Forest health conditions in North America

    International Nuclear Information System (INIS)

    Some of the greatest forest health impacts in North America are caused by invasive forest insects and pathogens (e.g., emerald ash borer and sudden oak death in the US), by severe outbreaks of native pests (e.g., mountain pine beetle in Canada), and fires exacerbated by changing climate. Ozone and N and S pollutants continue to impact the health of forests in several regions of North America. Long-term monitoring of forest health indicators has facilitated the assessment of forest health and sustainability in North America. By linking a nationwide network of forest health plots with the more extensive forest inventory, forest health experts in the US have evaluated current trends for major forest health indicators and developed assessments of future risks. Canada and Mexico currently lack nationwide networks of forest health plots. Development and expansion of these networks is critical to effective assessment of future forest health impacts. - The forests of North America continue to face many biotic and abiotic stressors including fragmentation, fires, native and invasive pests, and air pollution

  5. Exploring Advertising in Higher Education: An Empirical Analysis in North America, Europe, and Japan

    Science.gov (United States)

    Papadimitriou, Antigoni; Blanco Ramírez, Gerardo

    2015-01-01

    This empirical study explores higher education advertising campaigns displayed in five world cities: Boston, New York, Oslo, Tokyo, and Toronto. The study follows a mixed-methods research design relying on content analysis and multimodal semiotic analysis and employs a conceptual framework based on the knowledge triangle of education, research,…

  6. GHRSST Level 4 MUR North America Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced as a retrospective dataset at the JPL Physical...

  7. Gas deregulation in North America

    International Nuclear Information System (INIS)

    Contains Executive Summary and Chapters on: The North American gas industry; Upstream deregulation in the US and Canada; Retail regulation in the US and Canada; Customer choice in Pennsylvania and Ohio; Customer choice in Massachusetts; Deregulation legislation in Georgia; US pilot programme results; The Canadian experience; Market centres, hubs and storage; Marketers and trading companies; New roles for pipelines; Mergers and Joint ventures; Opportunities in Mexico; Conclusions - the pros and cons of deregulation. (Author)

  8. Uranium resources and geology of North America

    International Nuclear Information System (INIS)

    Since about the mid seventies, the International Atomic Energy Agency has held meetings on the geology and uranium resources of different geographic regions of the world. As a continuation of this series the Technical Committee Meeting on Uranium Resources and Geology of North America was held between 1-3 September 1987 in Saskatoon, Canada. The meeting took place in the University of Saskatchewan, hosted by the Department of Geological Sciences in cooperation with the Department of Energy, Mines and Resources Canada. Thirty-six technical papers were presented to a group of over 85 participants from seven countries. These papers provided an excellent coverage of uranium occurrences and deposits and their geological framework in Canada and the USA, with analogies from other parts of the world. North America, the region dealt with in this meeting, is of eminent significance for the world's uranium production and the nuclear industry. Total WOCA U-resources according to the classification developed by the IAEA and the Nuclear Energy Agency of OECD are periodically collected by these two organisations for their report on Uranium Resources, Production and Demand. Currently total WOCA known U resources recoverable at costs of less than $130/kg U or $50/lb U3O8) amount to 3.5 million t U, of which about 25% are located in North America, while the remainder is equally divided among Africa, Australia and the rest of WOCA (Asia, Europe, South America). Refs, figs and tabs

  9. North America Synoptic Weather Maps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Series of Synoptic Weather Maps. Maps contains a surface analysis comprised of plotted weather station observations, isobars indicating low and high-pressure...

  10. The EPR for North America

    International Nuclear Information System (INIS)

    As the supplier of 30 percent of the world's nuclear generating capacity, Framatome ANP, an AREVA and, Siemens company, has been a major contributor in the development of today's international fleet of nuclear power plants. Additionally, as a member of the AREVA global family of companies, Framatome ANP is a major element of the world's largest vertically integrated nuclear supplier. The EPR is the latest evolutionary pressurized water reactor design developed by Framatome ANP. The EPR benefits from the global operating experience of the international fleet of nuclear reactors. Framatome ANP is continuing to play a leadership role in the global renaissance of nuclear power. In December 2003, a Framatome ANP and Siemens consortium signed a firm price, turn-key contract with the Finnish utility TVO for an EPR to be constructed at the Olkiluoto site, In October 2004, it was announced that France would build its first EPR at the Flamanville site as a demonstration plant for a future series of advanced nuclear plants. In February 2005, Framatome ANP submitted a proposal for the supply of four EPR's in China which would be the beginning of a series of new construction in that country. Momentum is also building for new nuclear plants in Canada. Many reports in the past year, including those published by the Canadian Energy Research Institute, indicate that new electricity supplies will be required to meet the growing energy needs of Canada, especially in Ontario. The shutdown of approximately 7,000 MWe of coal-fired generation in Ontario by 2007 will further complicate the energy supply situation. Furthermore, various reports indicate as much as 24,000 MWe of new Canadian electricity generation could be required by 2020. Due to this developing potentially large electricity supply-demand imbalance, some industry officials believe the first North American order for a new nuclear plant will be placed in Canada. It is not surprising then that Framatome ANP is focusing on

  11. Fostering renewable electricity markets in North America

    International Nuclear Information System (INIS)

    This paper provided an overview of key market demand and supply drivers for the renewable electricity in Canada, the United States and Mexico. The aim of the paper was to assist North American governments in supporting the development of renewable electricity by addressing barriers that currently contribute to higher costs as well as challenges related to policy implementation. The paper outlined regulatory mandates and discussed issues related to voluntary purchases, and financial incentives. Current policy frameworks for renewable electricity were also examined. Opportunities for developing the renewable electricity market North America were explored. Wind power environmental standards were reviewed. Various green pricing schemes were discussed. The paper also included recommendations for the current electricity market as well as for members of the North American Agreement on Environmental Cooperation. 84 refs., 4 tabs., 7 figs

  12. North America and Asia Pacific LNG markets

    International Nuclear Information System (INIS)

    The liquefied natural gas (LNG) export opportunities in the Asia Pacific market were reviewed. Some of the differences that affect a North American LNG projects compared to more typical LNG projects were also outlined. The two main aspects of the LNG market in North America include the establishment of LNG import terminals on the east and southern coasts of the United States and the development of export oriented LNG projects. The Pac-Rim LNG project calls for initial delivery to South Korea of 4.0 MTPA by the end of 2000. A large LNG project has also been proposed for the year 2005 which would use Prudhoe Bay gas. Generally, in North America, there is little use for large scale LNG import projects because of the vast pipeline network that delivers gas reliably and at low cost anywhere in North America. However, LNG remains a good alternative for the Asia Pacific region because of the lack of a pipeline network. Also, Japan, Korea and Taiwan, the three main centers for LNG demand, have no domestic energy supplies and rely on imported energy sources. China is another major market opportunity for LNG. The Pac-Rim LNG project differs from others of its kind in that usually, an LNG project is based on the availability of large reservoirs of natural gas owned by state governments and involves production agreements with multi-national oil and gas companies. This scenario is simply not possible in Canada's deregulated environment. In contrast, the existence of upstream facilities, technical expertise, and low capital costs, hence reduced risks and time to develop an LNG project, gives Canada significant advantages. 3 tabs., 3 figs

  13. Fostering renewable energy markets in North America

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Jeremy [North American Comission for Environmental Cooperation (CEC), (United States)

    2007-06-15

    This presentation describes projects, programs and other issues addressed in order to promote renewable energy markets in North America. These are carried out by the North American Commission for Environmental Cooperation (CEC). In the first part of this presentation, there are going to be found some of the rules imposed by the North American Agreement on Environmental Cooperation (NAAEC). Then, it is shown the structure of the CEC as well as its programs, besides, there are presented the environment projects and the objectives along with their respective trades. There are described both benefits environmental and non-environmental. Also, there are shown the issues which the CEC is working in. And finally, it is shown a list mentioning the aspects that would change if: the expansion of the Mexico's Federal Commission of Electricity (CFE), happens, the grid-interconnected and the self supply of Renewable Electricity increase. [Spanish] En esta presentacion se describen los proyectos, los programas y otras cuestiones, cuyo objetivo es impulsar los mercados de energia renovable en America del Norte, realizadas por la North American Commission for Environmental Cooperation. En la primera parte, se encuentran algunas de las reglas impuestas por el Acuerdo de Cooperacion Ambiental de America del Norte (ACAAN). Enseguida, se muestra la estructura y los programas de la Comision para la Cooperacion Ambiental (CCA). Asimismo, se describen los proyectos ambientales, los objetivos junto con sus correspondientes tratados. Mas adelante, se explican tanto los beneficios ambientales como aquellos que no lo son. Igualmente, explican las cuestiones que podrian cambiar de: suceder la expansion de la Comision Federal de Electricidad (CFE), incrementarse el auto- suministro de la energia renovable y los sistemas interconectados.

  14. The thrust belts of Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Moulton, F.C.

    1993-08-01

    Most of the Basin and Range physiographic province of western North America is now believed to be part of the overthrust. The more obvious overthrust belt along the eastern edge of the Basin and Range Province is named the Sevier orogenic belt, where older rocks are observed thrust onto younger rocks. More detailed surface geological mapping, plus deep multiple-fold geophysical work and many oil and gas wildcat wells, have confirmed an east-vergent shortened and stacked sequence is present in many places in the Basin and Range. This western compressive deformed area in east central Nevada is now named the Elko orogenic belt by the U.S. Geological Survey. This older compressed Elko orogenic belt started forming approximately 250 m.y. ago when the North American plate started to move west as the Pangaea supercontinent started to fragment. The North American plate moved west under the sediments of the Miogeocline that were also moving west. Surface-formed highlands and oceanic island arcs on the west edge of the North American plate restricted the westward movement of the sediments in the Miogeocline, causing east-vergent ramp thrusts to form above the westward-moving North American plate. The flat, eastward-up-cutting thrust assemblages moved on the detachment surfaces.

  15. NOrth AMerica Soil (NOAM-SOIL) Database

    Science.gov (United States)

    Miller, D. A.; Waltman, S. W.; Geng, X.; James, D.; Hernandez, L.

    2009-05-01

    NOAM-SOIL is being created by combining the CONUS-SOIL database with pedon data and soil geographic data coverages from Canada and Mexico. Completion of the in-progress NOrth AMerica Soil (NOAM-SOIL) database will provide complete North America coverage comparable to CONUS. Canadian pedons, which number more than 500, have been painstakingly transcribed to a common format, from hardcopy, and key- entered. These data, along with map unit polygons from the 1:1,000,000 Soil Landscapes of Canada, will be used to create the required spatial data coverages. The Mexico data utilizes the INEGI 1:1,000,000 scale soil map that was digitized by U. S. Geological Survey EROS Data Center in the mid 1990's plus about 20,000 pedons. The pedon data were published on the reverse side of the paper 1:250,000 scale Soil Map of Mexico and key entered by USDA and georeferenced by Penn State to develop an attribute database that can be linked to the 1:1,000,000 scale Soil Map of Mexico based on taxonomic information and geographic proximity. The essential properties that will be included in the NOAM-SOIL data base are: layer thickness (depth to bedrock or reported soil depth); available water capacity; sand, silt, clay; rock fragment volume; and bulk density. For quality assurance purposes, Canadian and Mexican soil scientists will provide peer review of the work. The NOAM-SOIL project will provide a standard reference dataset of soil properties for use at 1km resolution by NACP modelers for all of North America. All data resources, including metadata and selected raw data, will be provided through the Penn State web site: Soil Information for Environmental Modeling and Ecosystem Management (www.soilinfo.psu.edu). Progress on database completion is reported.

  16. Browning boreal forests of western North America

    Science.gov (United States)

    Verbyla, David

    2011-12-01

    The GIMMS NDVI dataset has been widely used to document a 'browning trend' in North American boreal forests (Goetz et al 2005, Bunn et al 2007, Beck and Goetz 2011). However, there has been speculation (Alcaraz-Segura et al 2010) that this trend may be an artifact due to processing algorithms rather than an actual decline in vegetation activity. This conclusion was based primarily on the fact that GIMMS NDVI did not capture NDVI recovery within most burned areas in boreal Canada, while another dataset consistently showed post-fire increasing NDVI. I believe that the results of Alcaraz-Segura et al (2010) were due simply to different pixel sizes of the two datasets (64 km2 versus 1 km2 pixels). Similar results have been obtained from tundra areas greening in Alaska, with the results simply due to these pixel size differences (Stow et al 2007). Furthermore, recent studies have documented boreal browning trends based on NDVI from other sensors. Beck and Goetz (2011) have shown the boreal browning trend derived from a different sensor (MODIS) to be very similar to the boreal browning trend derived from the GIMMS NDVI dataset for the circumpolar boreal region. Parent and Verbyla (2010) found similar declining NDVI patterns based on NDVI from Landsat sensors and GIMMS NDVI in boreal Alaska. Zhang et al (2008) found a similar 'browning trend' in boreal North America based on a production efficiency model using an integrated AVHRR and MODIS dataset. The declining NDVI trend in areas of boreal North America is consistent with tree-ring studies (D'Arrigo et al 2004, McGuire et al 2010, Beck et al 2011). The decline in tree growth may be due to temperature-induced drought stress (Barber et al 2000) caused by higher evaporative demands in a warming climate (Lloyd and Fastie 2002). In a circumpolar boreal study, Lloyd and Bunn (2007) found that a negative relationship between temperature and tree-ring growth occurred more frequently in warmer parts of species' ranges

  17. Toxocariasis in North America: a systematic review.

    Directory of Open Access Journals (Sweden)

    Rachel M Lee

    2014-08-01

    Full Text Available Toxocariasis is an important neglected tropical disease that can manifest as visceral or ocular larva migrans, or covert toxocariasis. All three forms pose a public health problem and cause significant morbidity in areas of high prevalence. To determine the burden of toxocariasis in North America, we conducted a systematic review of the literature following PRISMA guidelines. We found 18 articles with original prevalence, incidence, or case data for toxocariasis. Prevalence estimates ranged from 0.6% in a Canadian Inuit community to 30.8% in Mexican children with asthma. Commonly cited risk factors included: African-American race, poverty, male sex, and pet ownership or environmental contamination by animal feces. Increased prevalence of Toxocara spp. infection was linked in a group of case control studies conducted in Mexico to several high risk groups including waste pickers, asthmatic children, and inpatient psychiatry patients. Further research is needed to determine the true current burden of toxocariasis in North America; however the prevalence estimates gathered in this review suggest that the burden of disease is significant.

  18. North America: US activity is unprecedented

    Energy Technology Data Exchange (ETDEWEB)

    1981-08-15

    For overall drilling activity in 1981, North America is expected to post a 20.9% increase over 1980 figures for a total of 90,347 wells. The growth is due solely to a 28.6% increase in US activity; Canada and Mexico show declines of 31.3% and 7.8%, respectively. Mid-year reports for the US included 36,776 wells, 7078 of them gas wells; of 7526 wildcats, 840 were gas-productive. The success rate for mid-year was 25.5%. The downturn in Canadian activity reflects the decrease in investments caused by the restructuring of the Canadian industry. Exploration is continuing, however, particularly in the east coast offshore region, the Beaufort Sea, and the Arctic Islands. The outlook in Mexico is highly promising: new fields are being discovered regularly in Campeche Bay, the Mesozoic region of Tabasco and Chiapas, the Sabinas Gulf region, and Chicontepec Paleocanyon. Since 1976, Petroleos Mexicanos has successfully reduced natural-gas flaring to less than 2% of production. Gas production increased by 22% in 1980, reaching 3.723 billion CF/day by December. Other drilling activity occurred in the West Indies and Caribbean Sea and parts of Central America.

  19. Socially Engaged Buddhist Nuns: Activism in Taiwan and North America

    Directory of Open Access Journals (Sweden)

    Karma Lekshe Tsomo

    2015-02-01

    Full Text Available The last decades of the twentieth century have been a time of new visibility and social activism for Buddhists in Taiwan and around the world. This paper compares the social engagement of nuns in the Chinese Buddhist tradition in Taiwan and North America. I would like to argue that whereas nuns in Taiwan have developed a variety of approaches to social involvement, their counterparts in the Chinese diaspora in North America have had to face a set of challenges specific to overseas Chinese communities in addition to Chinese Buddhist tradition. The article concludes with reflections on the prospects for nuns' social activism in Taiwan and North America in future years.

  20. Plutonium isotope ratio variations in North America

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, Robert E [Los Alamos National Laboratory; La Mont, Stephen P [Los Alamos National Laboratory; Eisele, William F [Los Alamos National Laboratory; Fresquez, Philip R [Los Alamos National Laboratory; Mc Naughton, Michael [Los Alamos National Laboratory; Whicker, Jeffrey J [Los Alamos National Laboratory

    2010-12-14

    Historically, approximately 12,000 TBq of plutonium was distributed throughout the global biosphere by thermo nuclear weapons testing. The resultant global plutonium fallout is a complex mixture whose {sup 240}Pu/{sup 239}Pu atom ratio is a function of the design and yield of the devices tested. The average {sup 240}Pu/{sup 239}Pu atom ratio in global fallout is 0.176 + 014. However, the {sup 240}Pu/{sup 239}Pu atom ratio at any location may differ significantly from 0.176. Plutonium has also been released by discharges and accidents associated with the commercial and weapons related nuclear industries. At many locations contributions from this plutonium significantly alters the {sup 240}Pu/{sup 239}Pu atom ratios from those observed in global fallout. We have measured the {sup 240}Pu/{sup 239}Pu atom ratios in environmental samples collected from many locations in North America. This presentation will summarize the analytical results from these measurements. Special emphasis will be placed on interpretation of the significance of the {sup 240}Pu/{sup 239}Pu atom ratios measured in environmental samples collected in the Arctic and in the western portions of the United States.

  1. Geographic distribution and dispersal of normapolles genera in North America

    Science.gov (United States)

    Tschudy, R.H.

    1981-01-01

    Normapolles pollen have been found in North America in Cretaceous and Lower Tertiary rocks from the eastern Atlantic Seaboard, the Mississippi embayment region and from the states and provinces from western North America as far north as the District of Mackenzie, Northwest Territories. Previous postulates relating to the Normapolles floral province (western Europe-eastern North America) were re-examined in the light of new finds of Normapolles genera in rocks from west of the Cretaceous epeiric seaway which separated the Normapolles province from the western North American Aquilapollenites province. A study of published occurrences of Normapolles genera and U.S. Geological Survey Denver Laboratory Normapolles records revealed that of the approximately 60 Normapolles genera recognized from western Europe, only 26 of these have been recognized from eastern North America. These data suggest that Normapolles-producing plants originated in western Europe and migrated to eastern North America prior to the opening of the north Atlantic seaway. Ten of these 26 genera also have been found in rocks from west of the Cretaceous epeiric seaway, suggesting that these genera were the only ones able to cross this barrier. At least six genera having Normapolles characteristics occur in eastern North America but have not yet been recorded from Europe. Two additional genera with Normapolles characteristics have been reported only from the Aquilapollenites province of western North America. Several discrepancies in the record need resolution, such as the latitudinal restriction of Thomsonipollis and Nudopollis to areas south 40??N latitude, the absence of records of Thomsonipollis east and north of central Georgia, and the absence of records of Kyandopollenites and Choanopollenites west of eastern Texas. These data show that the known boundaries of the Normapolles province are somewhat hazy and that firm conclusions regarding the geographic distribution and history of dispersal of

  2. Predictors of postherpetic neuralgia in patients with herpes zoster: a pooled analysis of prospective cohort studies from North and Latin America and Asia

    Directory of Open Access Journals (Sweden)

    Kosuke Kawai

    2015-05-01

    Conclusions: In addition to older age and severe acute pain, this study suggests that impaired physical and social functioning from acute zoster pain may play a role in the development of PHN in this prospective cohort study of HZ patients from North and Latin America and Asia.

  3. Analysis of the Emission Inventories and Model-Ready Emission Datasets of Europe and North America for Phase 2 of the AQMEII Project

    Science.gov (United States)

    This paper highlights the development of the emission inventories and emission processing for Europe (EU) and North America (NA) in the second phase of the Air Quality Model Evaluation International Initiative (AQMEII) project. The main purpose of the second phase of the AQMEII...

  4. Ice Age Geomorphology of North America

    Science.gov (United States)

    Wickert, A. D.; Anderson, R. S.; Mitrovica, J. X.; Picard, K.

    2012-12-01

    The Last Glacial Cycle in North America dramatically modified drainage patterns and geomorphology on a continental scale. As a consequence, the evolution of river systems holds information on the patterns of glaciation and isostatic response. This information can, in principle, be used to reconstruct the volumes of ice sheet sectors and eroded material by connecting the upstream ice sheets with stable isotope and other sedimentary records in offshore basins. Here we integrate this coupled geomorphic-hydrologic-glacial-sedimentary-paleoceanographic system to solve both the forward problem, how rivers evolve in response to Ice Age forcing, as well as the inverse problem, how fluvial systems record Quaternary history. The connections that define this system provide a link between climate and geomorphology that extends beyond the traditionally considered watershed-to-landscape scale by incorporating solid Earth deformations, large-scale shoreline migration, and the high amplitude changes in climate that drive the growth and decay of major ice sheets and water delivery to the bounding river systems. We address this continental scale problem using a valley-resolving drainage reconstruction that incorporates a realistic ice sheet history, a gravitationally self-consistent treatment of ice-age sea-level changes that includes shoreline migration, and precipitation and evapotranspiration retrodicted using general circulation model (GCM) runs. Drainage divides over the flat-lying North American interior migrate hundreds to thousands of kilometers in response to dynamic interactions between ice sheets and solid Earth response, and these changes coupled with post last glacial maximum (LGM) ice sheet melting drive high-amplitude variability in water and sediment discharge to the oceans. The Mackenzie River Delta records a sedimentary record produced by a highly non-eustatic sea level history and massive glacial sediment inputs routed along the axis that divided the Cordilleran

  5. Bathymetric Shaded Relief of North America - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Bathymetric Shaded Relief of North America map layer shows depth ranges using colors, with relief enhanced by shading. The image was derived from the National...

  6. A Bibliography of Italian Studies in North America

    Science.gov (United States)

    Cherubini, Jon C., Comp.

    1977-01-01

    This quarterly bibliography of Italian studies in North America includes books, bibliographies, and reviews of comparative literature studies, translations, and publications on art, music, philosophy, history, cinema, and sociology, which are closely related to literature. (SW)

  7. Topographic and Bathymetric Shaded Relief of North America - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Topographic and Bathymetric Shaded Relief of North America map layer shows depth and elevation ranges using colors, with relief enhanced by shading. The image...

  8. Grayscale North America Shaded Relief ? 1-Kilometer Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The grayscale North America shaded relief data were derived from the GTOPO30 elevation data. GTOPO30 is a global digital elevation model (DEM) with a horizontal...

  9. Imperiled Freshwater and Diadromous Fishes of North America

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — List of imperiled freshwater and diadromous fishes of North America as determined by the 2008 American Fisheries Society (AFS) Endangered Species Committee (ESC) on...

  10. Classification of Forest Fragmentation in North America - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of North America including the Caribbean and most of Mexico. The map layer is an excerpt from a global assessment of forest...

  11. The Hispanic Heritage of North America: Commemorating 500 Years

    Science.gov (United States)

    Cruz, Barbara C.

    2013-01-01

    In April 2013, Florida will commemorate Juan Ponce de Leon's historic voyage. Yet Ponce de Leon's arrival was, in several important ways, not just the beginning of Spain's presence in Florida, but in North America as a whole. Today, the historical Spanish influence on America is palpable--in culture, language, politics, and more. This year marks…

  12. Ancient DNA analysis of mid-holocene individuals from the Northwest Coast of North America reveals different evolutionary paths for mitogenomes.

    Directory of Open Access Journals (Sweden)

    Yinqiu Cui

    Full Text Available To gain a better understanding of North American population history, complete mitochondrial genomes (mitogenomes were generated from four ancient and three living individuals of the northern Northwest Coast of North America, specifically the north coast of British Columbia, Canada, current home to the indigenous Tsimshian, Haida, and Nisga'a. The mitogenomes of all individuals were previously unknown and assigned to new sub-haplogroup designations D4h3a7, A2ag and A2ah. The analysis of mitogenomes allows for more detailed analyses of presumed ancestor-descendant relationships than sequencing only the HVSI region of the mitochondrial genome, a more traditional approach in local population studies. The results of this study provide contrasting examples of the evolution of Native American mitogenomes. Those belonging to sub-haplogroups A2ag and A2ah exhibit temporal continuity in this region for 5000 years up until the present day. Of possible associative significance is that archaeologically identified house structures in this region maintain similar characteristics for this same period of time, demonstrating cultural continuity in residence patterns. The individual dated to 6000 years before present (BP exhibited a mitogenome belonging to sub-haplogroup D4h3a. This sub-haplogroup was earlier identified in the same general area at 10300 years BP on Prince of Wales Island, Alaska, and may have gone extinct, as it has not been observed in any living individuals of the Northwest Coast. The presented case studies demonstrate the different evolutionary paths of mitogenomes over time on the Northwest Coast.

  13. Height System Unification in North America

    Science.gov (United States)

    Sideris, Michael; Amjadiparvar, Babak

    2015-04-01

    GOCE has contributed important gravity information towards the definition and realization of the new North American height reference system. In addition to the new gravimetric geoid models based on GOCE, offsets of the classical levelling-based vertical datums in North America, namely CGVD28 in Canada and NAVD88 in the USA and Mexico, can be computed with respect to a global equipotential surface defined by means of a GOCE-based geoid. Although the two datums will eventually be replaced by a common and continent-wide vertical datum (and in fact the new Canadian height datum established in 2013 is already geoid based), their connection and unification is of great interest to the scientific and user communities. This study investigates the practical implementation of the geodetic boundary value problem (GBVP) approach as a rigorous method for unifying classical levelling-based vertical datums. The so-called indirect bias term, the effect of the GOCE geoid omission error, the effect of the systematic levelling datum errors and distortions, and the effect of the data errors on the datum unification are of great importance for the practical implementation of this approach. These factors are investigated numerically using the GNSS-levelling and tide gauge (TG) stations in Canada, the USA, Alaska, and Mexico. The results show that the indirect bias term can be omitted if a GOCE-based global geopotential model is used in geoid computation. This is significant because the omission of the indirect bias term simplifies the geoid computations as well as the linear system of equations for the estimation of datum offsets. Because of the existing systematic levelling errors and distortions in the Canadian and US levelling networks, the datum offsets are investigated in eight smaller regions along Canadian and US coastal areas instead of over the whole North American land mass. The effect of the omission error on the datum offsets decreases significantly in areas with good

  14. Tectonic history of the southeastern North America

    Energy Technology Data Exchange (ETDEWEB)

    Hatcher, R.D. Jr. (Univ. of Tennessee, Knoxville, TN (United States). Dept. of Geological Sciences Oak Ridge National Lab., TN (United States))

    1993-03-01

    The present-day configuration of the crust of southeastern North America (SENA) is the product of a lengthy history traceable through more than 1 billion yr. of geologic time. The Appalachians (AP) record complete Wilson cycles of opening and closing of several oceans from ca. 690 Ma to 245 M. The final event forming the AP was the collision of SENA with Gondwana to form the supercontinent Pangaea. The Ouachitas (OA) had a somewhat different history culminating with island-arc collision during the Pennsylvanian--before the final collision began in the AP. SENA faced the open lapetos ocean no earlier than the Early Cambrian. The AP and OA were built on an earlier margin formed by rifting of the Rodonia super-continent formed by construction of the 1.2 to 1.0 Ga Grenville orogen, and farther west, a crust formed by still earlier (1.3 and 1.8 Ga) events. Recent suggestions that part of the AP platform is in Argentina raises the possibility that a fragment was rifted from between the AP and OA during the early Paleozoic. The crust beneath the Mississippi Embayment is atypical of continental crust, and would have been rifted during the Neoproterozoic and early Paleozoic. The Argentine fragment may have been removed along a transform that was reactivated several times since. Northern Pangaea was rifted during the Late Triassic and Early Jurassic and SENA once again faced open ocean-the nascent present Atlantic (AT) when spreading began. The Gulf of Mexico (GOM) also opened then forming extensive salt deposits. The AT opened partly along the old suture, but produced a failed rift in GA and FL leaving a piece of Africa forming the crust beneath the Coastal Plain as far south as central FL. The overlying sediments record recurrent uplift and decay of the AP and OA, cooling of new AT oceanic crust, eustatic sea-level changes during the Mesozoic and Cenozoic, and uplift of the Rockies providing a new source of voluminous detritus that is still being deposited in the GOM.

  15. Geomorphic analysis of transient landscapes in the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American–Caribbean–Cocos plate boundary

    OpenAIRE

    L. Andreani; R. Gloaguen

    2016-01-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. We intend to characterize and understand the complex tectonic setting that produced an intricate pattern of landscapes using tectonic geomorphology, as well as available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landsc...

  16. Atlas of Relations Between Climatic Parameters and Distributions of Important Trees and Shrubs in North America - Ecoregions of North America

    Science.gov (United States)

    Thompson, Robert S.; Anderson, Katherine H.; Pelltier, Richard T.; Shafer, Sarah L.; Bartlein, Patrick J.

    2007-01-01

    Climate is the primary factor controlling the continental-scale distribution of plant species, although the relations between climatic parameters and species' ranges are only now beginning to be quantified. This volume examines the relations between climate and the distributions of (1) Kuchler's 'potential natural vegetation' categories for the 48 contiguous States of the United States of America, (2) Bailey's ecoregions of North America, and (3) World Wildlife Fund's ecoregions of North America. For these analyses, we employed a 25-kilometer equal-area grid of modern climatic and bioclimatic parameters for North America, coupled with presence-absence data for the occurrence of each ecoregion under the three classification systems under consideration. The resulting relations between climate and ecoregion distributions are presented in graphical and tabular form. Presentation of ecoregion-climate relations here is intended to be useful for a greater understanding of ecosystem evolution, ecosystem dynamics, and potential effects of future climate change on ecoregions.

  17. [CO2 Budget and Atmospheric Rectification (COBRA) Over North America

    Science.gov (United States)

    2004-01-01

    The purpose of the CO2 Budget and Rectification Airborne (COBRA) study was to assess terrestrial sources and sinks of carbon dioxide using an air-borne study. The study was designed to address the measurement gap between plot-scale direct flux measurements and background hemispheric-scale constraints and to refine techniques for measuring terrestrial fluxes at regional to continental scales. The initial funded effort (reported on here) was to involve two air-borne campaigns over North America, one in summer and one in winter. Measurements for COBRA (given the acronym C02BAR in the initial proposal) were conducted from the University of North Dakota Citation 11, a twin-engine jet aircraft capable of profiling from the surface to 12 km and cruising for up to 4 hours and 175m/s. Onboard instrumentation measured concentrations of CO2, CO, and H2O, and meteorological parameters at high rates. In addition, two separate flask sampling systems collected discrete samples for laboratory analysis of CO2,CO, CH4, N2O, SF6, H2, 13CO2, C18O16O,O2/N2, and Ar/N2. The project involved a collaboration between a number of institutions, including (but not limited to) Harvard, NOAA-CMDL, the University of North Dakota, and Scripps.

  18. Quantifying sources of black carbon in Western North America using observationally based analysis and an emission tagging technique in the Community Atmosphere Model

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2015-05-01

    Full Text Available The Community Atmosphere Model (CAM5, equipped with a technique to tag black carbon (BC emissions by source regions and types, has been employed to establish source-receptor relationships for atmospheric BC and its deposition to snow over Western North America. The CAM5 simulation was conducted with meteorological fields constrained by reanalysis for year 2013 when measurements of BC in both near-surface air and snow are available for model evaluation. We find that CAM5 has a significant low bias in predicted mixing ratios of BC in snow but only a small low bias in predicted atmospheric concentrations over the Northwest USA and West Canada. Even with a strong low bias in snow mixing ratios, radiative transfer calculations show that the BC-in-snow darkening effect is substantially larger than the BC dimming effect at the surface by atmospheric BC. Local sources contribute more to near-surface atmospheric BC and to deposition than distant sources, while the latter are more important in the middle and upper troposphere where wet removal is relatively weak. Fossil fuel (FF is the dominant source type for total column BC burden over the two regions. FF is also the dominant local source type for BC column burden, deposition, and near-surface BC, while for all distant source regions combined the contribution of biomass/biofuel (BB is larger than FF. An observationally based Positive Matrix Factorization (PMF analysis of the snow-impurity chemistry is conducted to quantitatively evaluate the CAM5 BC source-type attribution. While CAM5 is qualitatively consistent with the PMF analysis with respect to partitioning of BC originating from BB and FF emissions, it significantly underestimates the relative contribution of BB. In addition to a possible low bias in BB emissions used in the simulation, the model is likely missing a significant source of snow darkening from local soil found in the observations.

  19. GHRSST Level 4 RTO Terra MODIS-AMSRE Night North America Regional Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the JPL Physical...

  20. GHRSST Level 4 RTO Terra MODIS-AMSRE Day North America Regional Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the JPL Physical...

  1. GHRSST Level 4 RTO Aqua MODIS-AMSRE Night North America Regional Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the JPL Physical...

  2. GHRSST Level 4 RTO Aqua MODIS-AMSRE Day North America Regional Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the JPL Physical...

  3. Socially Engaged Buddhist Nuns: Activism in Taiwan and North America

    OpenAIRE

    Karma Lekshe Tsomo

    2015-01-01

    The last decades of the twentieth century have been a time of new visibility and social activism for Buddhists in Taiwan and around the world. This paper compares the social engagement of nuns in the Chinese Buddhist tradition in Taiwan and North America. I would like to argue that whereas nuns in Taiwan have developed a variety of approaches to social involvement, their counterparts in the Chinese diaspora in North America have had to face a set of challenges specific to overseas Chinese com...

  4. Computer codes for birds of North America

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Purpose of paper was to provide a more useful way to provide codes for all North American species, thus making the list useful for virtually all projects concerning...

  5. Fuyao Aims for North America Expansion

    Institute of Scientific and Technical Information of China (English)

    JESSY ZHANG

    2006-01-01

    @@ China's auto-part industry has grown powerful enough to shake the world. Most recently, the acquisition attempt by a Chinese autoglass maker on a North Americac project shocked competitors.Fuyao Glass, China's largest and the world's sixth largest autoglass maker, announced thatthey have now entered the final stage of acqtuiring the North American glass-making assets of Ford Motor Co. which has been struggling through a painful restructuring.

  6. Hydrogeology in North America: past and future

    Science.gov (United States)

    Narasimhan, T. N.

    2005-03-01

    This paper is a retrospective on the evolution of hydrogeology in North America over the past two centuries, and a brief speculation of its future. The history of hydrogeology is marked by developments in many different fields such as groundwater hydrology, soil mechanics, soil science, economic geology, petroleum engineering, structural geology, geochemistry, geophysics, marine geology, and more recently, ecology. The field has been enriched by the contributions of distinguished researchers from all these fields. At present, hydrogeology is in transition from a state of discovering new resources and exploiting them efficiently for maximum benefit, to one of judicious management of finite, interconnected resources that are vital for the sustenance of humans and other living things. The future of hydrogeology is likely to be dictated by the subtle balance with which the hydrological, erosional, and nutritional cycles function, and the decision of a technological society to either adapt to the constraints imposed by the balance, or to continue to exploit hydrogeological systems for maximum benefit. Although there is now a trend towards ecological and environmental awareness, human attitudes could change should large parts of the populated world be subjected to the stresses of droughts that last for many decades. Cet article est une rétrospective de l'évolution de l'hydrogéologie en Amérique du Nord sur les deux derniers siècles, et une brève évaluation de son futur. L'histoire de l'hydrogéologie est marquée par le développement de plusieurs techniques de terrain telles, l'hydrologie des eaux souterraines, la mécanique des sols, les sciences du sol, la géologie économique, l' ingénierie pétrolière, la géologie structurale, la géochimie, la géophysique, la géologie marine et plus récemment l'écologie. La science a été enrichie par la contribution de plusieurs chercheurs distingués, provenant de toutes ces branches. A présent, l

  7. Three-Level Mixed-Effects Logistic Regression Analysis Reveals Complex Epidemiology of Swine Rotaviruses in Diagnostic Samples from North America.

    Science.gov (United States)

    Homwong, Nitipong; Diaz, Andres; Rossow, Stephanie; Ciarlet, Max; Marthaler, Douglas

    2016-01-01

    Rotaviruses (RV) are important causes of diarrhea in animals, especially in domestic animals. Of the 9 RV species, rotavirus A, B, and C (RVA, RVB, and RVC, respectively) had been established as important causes of diarrhea in pigs. The Minnesota Veterinary Diagnostic Laboratory receives swine stool samples from North America to determine the etiologic agents of disease. Between November 2009 and October 2011, 7,508 samples from pigs with diarrhea were submitted to determine if enteric pathogens, including RV, were present in the samples. All samples were tested for RVA, RVB, and RVC by real time RT-PCR. The majority of the samples (82%) were positive for RVA, RVB, and/or RVC. To better understand the risk factors associated with RV infections in swine diagnostic samples, three-level mixed-effects logistic regression models (3L-MLMs) were used to estimate associations among RV species, age, and geographical variability within the major swine production regions in North America. The conditional odds ratios (cORs) for RVA and RVB detection were lower for 1-3 day old pigs when compared to any other age group. However, the cOR of RVC detection in 1-3 day old pigs was significantly higher (p 55 day old age groups. Furthermore, pigs in the 21-55 day old age group had statistically higher cORs of RV co-detection compared to 1-3 day old pigs (p epidemiology is complex, and RV species are associated with different age groups and vary by regions in North America. PMID:27145176

  8. Three-Level Mixed-Effects Logistic Regression Analysis Reveals Complex Epidemiology of Swine Rotaviruses in Diagnostic Samples from North America

    Science.gov (United States)

    Diaz, Andres; Rossow, Stephanie; Ciarlet, Max; Marthaler, Douglas

    2016-01-01

    Rotaviruses (RV) are important causes of diarrhea in animals, especially in domestic animals. Of the 9 RV species, rotavirus A, B, and C (RVA, RVB, and RVC, respectively) had been established as important causes of diarrhea in pigs. The Minnesota Veterinary Diagnostic Laboratory receives swine stool samples from North America to determine the etiologic agents of disease. Between November 2009 and October 2011, 7,508 samples from pigs with diarrhea were submitted to determine if enteric pathogens, including RV, were present in the samples. All samples were tested for RVA, RVB, and RVC by real time RT-PCR. The majority of the samples (82%) were positive for RVA, RVB, and/or RVC. To better understand the risk factors associated with RV infections in swine diagnostic samples, three-level mixed-effects logistic regression models (3L-MLMs) were used to estimate associations among RV species, age, and geographical variability within the major swine production regions in North America. The conditional odds ratios (cORs) for RVA and RVB detection were lower for 1–3 day old pigs when compared to any other age group. However, the cOR of RVC detection in 1–3 day old pigs was significantly higher (p 55 day old age groups. Furthermore, pigs in the 21–55 day old age group had statistically higher cORs of RV co-detection compared to 1–3 day old pigs (p epidemiology is complex, and RV species are associated with different age groups and vary by regions in North America. PMID:27145176

  9. Three-Level Mixed-Effects Logistic Regression Analysis Reveals Complex Epidemiology of Swine Rotaviruses in Diagnostic Samples from North America.

    Directory of Open Access Journals (Sweden)

    Nitipong Homwong

    Full Text Available Rotaviruses (RV are important causes of diarrhea in animals, especially in domestic animals. Of the 9 RV species, rotavirus A, B, and C (RVA, RVB, and RVC, respectively had been established as important causes of diarrhea in pigs. The Minnesota Veterinary Diagnostic Laboratory receives swine stool samples from North America to determine the etiologic agents of disease. Between November 2009 and October 2011, 7,508 samples from pigs with diarrhea were submitted to determine if enteric pathogens, including RV, were present in the samples. All samples were tested for RVA, RVB, and RVC by real time RT-PCR. The majority of the samples (82% were positive for RVA, RVB, and/or RVC. To better understand the risk factors associated with RV infections in swine diagnostic samples, three-level mixed-effects logistic regression models (3L-MLMs were used to estimate associations among RV species, age, and geographical variability within the major swine production regions in North America. The conditional odds ratios (cORs for RVA and RVB detection were lower for 1-3 day old pigs when compared to any other age group. However, the cOR of RVC detection in 1-3 day old pigs was significantly higher (p 55 day old age groups. Furthermore, pigs in the 21-55 day old age group had statistically higher cORs of RV co-detection compared to 1-3 day old pigs (p < 0.001. The 3L-MLMs indicated that RV status was more similar within states than among states or within each region. Our results indicated that 3L-MLMs are a powerful and adaptable tool to handle and analyze large-hierarchical datasets. In addition, our results indicated that, overall, swine RV epidemiology is complex, and RV species are associated with different age groups and vary by regions in North America.

  10. On cold spells in North America and storminess in western Europe

    Science.gov (United States)

    Messori, Gabriele; Caballero, Rodrigo; Gaetani, Marco

    2016-06-01

    We discuss the dynamical and statistical links between cold extremes over eastern North America and storminess over western Europe, with a focus on the midlatitude jet stream, the North Atlantic Oscillation (NAO) and the Pacific-North American Pattern (PNA). The analysis is performed on the European Centre for Medium-Range Weather Forecasts 20th Century Reanalysis. The large-scale circulation associated with the cold spells corresponds to advection of cold air from the Arctic region into North America and to a very zonal and intense North Atlantic jet, shifted persistently south of its climatological location. These features of the Atlantic jet are conducive to destructive windstorms and intense precipitation over a large part of southern and continental Europe and the British Isles. The cold spells are preceded by a negative NAO and followed by a positive PNA; however, we interpret the associated circulation anomalies as being distinct from these standard modes of climate variability.

  11. A metagenomic analysis of pandemic influenza A (2009 H1N1 infection in patients from North America.

    Directory of Open Access Journals (Sweden)

    Alexander L Greninger

    Full Text Available Although metagenomics has been previously employed for pathogen discovery, its cost and complexity have prevented its use as a practical front-line diagnostic for unknown infectious diseases. Here we demonstrate the utility of two metagenomics-based strategies, a pan-viral microarray (Virochip and deep sequencing, for the identification and characterization of 2009 pandemic H1N1 influenza A virus. Using nasopharyngeal swabs collected during the earliest stages of the pandemic in Mexico, Canada, and the United States (n = 17, the Virochip was able to detect a novel virus most closely related to swine influenza viruses without a priori information. Deep sequencing yielded reads corresponding to 2009 H1N1 influenza in each sample (percentage of aligned sequences corresponding to 2009 H1N1 ranging from 0.0011% to 10.9%, with up to 97% coverage of the influenza genome in one sample. Detection of 2009 H1N1 by deep sequencing was possible even at titers near the limits of detection for specific RT-PCR, and the percentage of sequence reads was linearly correlated with virus titer. Deep sequencing also provided insights into the upper respiratory microbiota and host gene expression in response to 2009 H1N1 infection. An unbiased analysis combining sequence data from all 17 outbreak samples revealed that 90% of the 2009 H1N1 genome could be assembled de novo without the use of any reference sequence, including assembly of several near full-length genomic segments. These results indicate that a streamlined metagenomics detection strategy can potentially replace the multiple conventional diagnostic tests required to investigate an outbreak of a novel pathogen, and provide a blueprint for comprehensive diagnosis of unexplained acute illnesses or outbreaks in clinical and public health settings.

  12. Cortinarius bovarius (Agaricales, a new species from western North America

    Directory of Open Access Journals (Sweden)

    Kare Liimatainen

    2013-05-01

    Full Text Available Cortinarius bovarius sp. nov., a conifer associated taxon growing on calcareous ground, is described from western North America. Phylogenetic relationships and species limits were investigated using rDNA ITS and nuclear rpb2 sequences, morphological and ecological data. The species belongs to section Bovini and its closest relative is European C. bovinus.

  13. Key Challenges to Collegiate Music Education Programs in North America

    Science.gov (United States)

    Jones, Patrick M.

    2012-01-01

    Higher education is the linchpin of music education in North America. It is primarily in collegiate institutions that music teachers are educated throughout the life cycles of their careers. This begins with preservice programs, typically at the baccalaureate level, and continues with in-service professional development and graduate degree…

  14. Aridland Springs in North America: Ecology and Conservation

    OpenAIRE

    Kate Smith

    2012-01-01

    Review of Aridland Springs in North America: Ecology and Conservation. Lawrence E. Stevens and Vicky J. Meretsky, editors. 2008. The University of Arizona Press and the Arizona‐SonoraDesert Museum, Tucson.Pp. 406, 4 black‐and‐white photos, 28 illustrations, 38 tables, 8 maps, bibliography.$75.00 (cloth). ISBN 978‐0‐8165‐2645‐1.

  15. Academic Talent Development in North America and Europe

    Science.gov (United States)

    Jarvin, Linda; Subotnik, Rena F.

    2015-01-01

    First we describe one particular model of talent development (Jarvin and Subotnik in The handbook of secondary gifted education. Prufrock Press, Waco, 2006) and situate it in perspective to other models developed in North America and Europe. We then discuss the implications of this view of giftedness on education and review related resources and…

  16. New digital magnetic anomaly database for North America

    Science.gov (United States)

    Finn, C.A.; Pilkington, M.; Cuevas, A.; Hernandez, I.; Urrutia, J.

    2001-01-01

    The Geological Survey of Canada (GSC), U.S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM) are compiling an upgraded digital magnetic anomaly database and map for North America. This trinational project is expected to be completed by late 2002.

  17. The Hermit Crabs (Crustacea Decapoda, Paguridea) of Northwestern North America

    NARCIS (Netherlands)

    Mclaughlin, P.A.

    1974-01-01

    A systematic study has been made of the Paguridea (exclusive of the Lithodidae) from northwestern North America. In addition to the redescriptions of all known species, two subgenera are herein raised to generic rank and a new genus is described. Several systematic problems have been resolved, and h

  18. The medicinal use of chocolate in early North America.

    Science.gov (United States)

    Pucciarelli, Deanna L; Grivetti, Louis E

    2008-10-01

    The medicinal use of chocolate has a long history in North America dating back to the 16th century. From Mesoamerican Codices and European Treatises scholars have determined that for hundreds of years the beverage called chocolate was administered to the sick and prescribed homeopathically to prevent illness. Yet, little scholarship exists that focuses on medicinal chocolate usage in early North America (18th-19th century). This paper examines medical practices during this era and associated medicinal norms with special attention given to chocolate/cocoa usage. Given the current scientific attention on the relationship between dark chocolate consumption and heart disease attenuation it is timely to investigate and chronicle America's medical forebears' understanding of, and practices related to, the medicinal use of chocolate. Indeed, there is a significant amount of literature to suggest that chocolate was used for wellness and to treat illness. PMID:18683818

  19. Preparation of mercury emissions inventory for eastern North America.

    Science.gov (United States)

    Walcek, Chris; De Santis, Steven; Gentile, Thomas

    2003-01-01

    Point and area inventories of anthropogenic mercury emissions documented by US and Canadian environmental agencies have been aggregated into a single archive for analysis and air pollution modeling work. For 5341 point sources and 1634 aggregated area sources, mercury emissions are apportioned among elemental gaseous [Hg(0)], reactive gaseous[Hg(II)], and particulate [Hg(p)] emissions using speciation factors derived from available monitoring measurements. According to this inventory, 4.82 x 10(5) mol of mercury were emitted in calendar year 1996 in the latitude range 24-51 degrees north, and longitude range 64-91 degrees west, which covers most of North America east of the Mississippi River. Using speciation factors consistent with past emission source studies, we find the relative emission proportions among Hg(0):Hg(II):Hg(p) species are 47:35:18. Maps of the various mercury species' emissions patterns are presented. Gridded emission patterns show local mercury emission extremes associated with individual cement production and municipal incineration facilities, and in contrast to past inventories, population centers do not stand out. Considerable uncertainties are still present in estimating emissions from large point sources, as are methods of apportioning emissions among various mercury species. PMID:12667765

  20. Projected hydrogen cost from methane reforming for North America 2015-2050

    International Nuclear Information System (INIS)

    The Hydrogen Futures Simulation Model (H2Sim) was used to project the cost for hydrogen at the point of sale to light duty vehicles for distributed, small-scale steam methane reforming. Projections cover the period from 2010-2050 in North America, and take into account assumptions about the quantity of recoverable natural gas remaining in North America. We conclude that there is a window for distributed reforming to play a positive role in supplying a H2 fuel infrastructure, but this window is closing rapidly. The analysis assumes that production from natural gas reserves in North America will peak sometime before 2050 and demand will cause the price to rise after the peak of production in a manner consistent with Hotelling's model. We consider three scenarios for when the peak occurs, and evaluate the impact on the cost of hydrogen fuel produced via distributed small scale reforming in these three scenarios. (authors)

  1. Late Cretaceous restructuring of terrestrial communities facilitated the end-Cretaceous mass extinction in North America

    Science.gov (United States)

    Mitchell, Jonathan S.; Roopnarine, Peter D.; Angielczyk, Kenneth D.

    2012-11-01

    The sudden environmental catastrophe in the wake of the end-Cretaceous asteroid impact had drastic effects that rippled through animal communities. To explore how these effects may have been exacerbated by prior ecological changes, we used a food-web model to simulate the effects of primary productivity disruptions, such as those predicted to result from an asteroid impact, on ten Campanian and seven Maastrichtian terrestrial localities in North America. Our analysis documents that a shift in trophic structure between Campanian and Maastrichtian communities in North America led Maastrichtian communities to experience more secondary extinction at lower levels of primary production shutdown and possess a lower collapse threshold than Campanian communities. Of particular note is the fact that changes in dinosaur richness had a negative impact on the robustness of Maastrichtian ecosystems against environmental perturbations. Therefore, earlier ecological restructuring may have exacerbated the impact and severity of the end-Cretaceous extinction, at least in North America.

  2. Lianas as invasive species in North America: Chapter 28

    Science.gov (United States)

    Leicht-Young, Stacey A.; Pavlovic, Noel B.

    2015-01-01

    Liana diversity is typically low in the temperate zones; however, the influx of non-native invasive liana species in North America has increased local diversity at the expense of native habitats and species. Some of the most illustrative studies of invasive lianas in temperate North America compared the biological traits of invasive lianas with native congeners or ecological analogs. The majority of these studies focused on two species, Celastrus orbiculatus (oriental bittersweet) and Lonicera japonica (Japanese honeysuckle). Temperate zone lianas generally have higher photosynthetic rates than other early successional species and their host trees. Invasive lianas are having an increasing impact on the dynamics and trajectories of North American plant communities. They often exhibit superior growth and survival compared to their native counterparts, and in some cases, invasive lianas may directly contribute to the decline of their native correlates.

  3. Geomorphic analysis of transient landscapes from the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American-Caribbean-Cocos plate boundary

    Science.gov (United States)

    Andreani, L.; Gloaguen, R.

    2015-09-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. The complex tectonic setting produced an intricate pattern of landscapes that we try to systemize using remote sensing tectonic geomorphology and available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landscapes in northern Central America. We also analyze the drainage network from the Sierra Madre de Chiapas and Maya Mountains in order to extract information about potential vertical displacements. Our results suggest that most of the landscapes of the Sierra Madre de Chiapas and Maya Mountains are in transient stage. Topographic profiles and morphometric maps highlight elevated relict surfaces that are characterized by a low amplitude relief. The river longitudinal profiles display upper reaches witnessing these relict landscapes while lower segments characterized by multiple knickpoints, that adjust to new base-level conditions. These results backed by published GPS and seismotectonic data allow us to refine and extend existing geodynamic models of the triple junction. Relict landscapes are delimited by faults and thus result from a tectonic control. The topography of the Sierra Madre de Chiapas evolved as the result of (1) the inland migration of deformation related to the coupling between the Chiapas Massif and the Cocos fore-arc sliver, and (2) the compression along the northern tip of the Central America Volcanic Arc. Although most of the shortening between the Cocos fore-arc sliver and the North American plate is accommodated within the Sierra de Chiapas and Sierra de los Cuchumatanes, a small part may be still transmitted to the Maya Mountains and the Belize margin through a "rigid" Petén basin.

  4. TRADE LIBERALIZATION AND INTERNATIONAL MERGER IN COURNOT INDUSTRIES: THE CASE OF BARLEY MALTING IN NORTH AMERICA

    OpenAIRE

    Buschena, David E.; Gray, Richard S.

    1998-01-01

    When free trade merges formally distinct non-competitive industries, welfare should increase. Additional incentives for mergers may reduce these gains from free trade. We show the importance of such arguments in an analysis of the malting barley industry in North America before and after the Canadian/U.S. free trade agreement.

  5. Cortinarius section Sanguinei in North America.

    Science.gov (United States)

    Niskanen, Tuula; Liimatainen, Kare; Ammirati, Joseph F; Hughes, Karen

    2013-01-01

    The North American species of Cortinarius section Sanguinei were studied using morphological characters and ITS and RPB2 sequence data. Several type collections also were examined. Four species were identified: C. harrisonii sp. nov, C. neosanguineus sp. nov., C. sanguineus and C. sierraensis comb. nov. Of these, C. sanguineus also occurs in Europe together with C. puniceus, a fifth member of the section. Typical features of these species include ± red, fairly small basidiomata, stipe basal mycelium often with yellow to reddish yellow tints, amygdaloid to ellipsoid spores, and aniline-red lamellar trama and pileipellis hyphae when mounted in KOH. Two other species with red lamellae C. marylandensis comb. nov. and C. smithii stat. nov. & nom. nov. also are discussed. PMID:22962360

  6. A magmatic probe of dynamic topography beneath western North America

    Science.gov (United States)

    Klöcking, M.; White, N. J.; Maclennan, J.

    2014-12-01

    A region centered on the Yellowstone hotspot and encompassing the Colorado Plateau sits at an elevation 2 km higher than the cratonic North America. This difference broadly coincides with tomographically observed variations in lithospheric thickness: ~120 km beneath western North America, ~240 km beneath the craton. Thermochronology of the Grand Canyon area, sedimentary flux to the Gulf of Mexico, and river profile inversion all suggest that regional uplift occurred in at least two separate stages. High resolution seismic tomographic models, using USArray data, have identified a ring of low velocity material beneath the edges of the Colorado Plateau. Magmatism coincides with these low velocity zones and shows distinct phases: an overall increase in volume around 40 Ma and a change from lithospheric to asthenospheric signatures around 5 Ma. Volcanism is also observed to migrate north-east with time. Here, we attempt to integrate these different observations with lithospheric thickness. A dynamic topography model of progressive lithospheric erosion over a hot mantle plume might account for uplift as well as the temporal and spatial distribution of magmatism across western North America. Thinning of the lithosphere around the edges of the Colorado Plateau in combination with the hotter mantle potential temperature of a plume could create isostatic and dynamic uplift as well as allowing for melt production. To test this model, we have analysed around 100 samples from volcanic centers across western North America by ICP-MS for rare earth elements (REE). Most of the samples are younger than 5 Ma, and all of them have previously been analysed by XRF. Using trace element ratios such as La/Yb and Nb/Y we assess depth of melting and melt fraction, respectively. In addition, we use REE inversion modelling to estimate melt fractions as a function of depth and temperature of melting. The results are compared to existing constraints on lithospheric thickness and mantle potential

  7. Health outcomes among HIV-positive Latinos initiating antiretroviral therapy in North America versus Central and South America

    Science.gov (United States)

    Cesar, Carina; Koethe, John R; Giganti, Mark J; Rebeiro, Peter; Althoff, Keri N; Napravnik, Sonia; Mayor, Angel; Grinsztejn, Beatriz; Wolff, Marcelo; Padgett, Denis; Sierra-Madero, Juan; Gotuzzo, Eduardo; Sterling, Timothy R; Willig, James; Levison, Julie; Kitahata, Mari; Rodriguez-Barradas, Maria C; Moore, Richard D; McGowan, Catherine; Shepherd, Bryan E; Cahn, Pedro

    2016-01-01

    Introduction Latinos living with HIV in the Americas share a common ethnic and cultural heritage. In North America, Latinos have a relatively high rate of new HIV infections but lower rates of engagement at all stages of the care continuum, whereas in Latin America antiretroviral therapy (ART) services continue to expand to meet treatment needs. In this analysis, we compare HIV treatment outcomes between Latinos receiving ART in North America versus Latin America. Methods HIV-positive adults initiating ART at Caribbean, Central and South America Network for HIV (CCASAnet) sites were compared to Latino patients (based on country of origin or ethnic identity) starting treatment at North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) sites in the United States and Canada between 2000 and 2011. Cox proportional hazards models compared mortality, treatment interruption, antiretroviral regimen change, virologic failure and loss to follow-up between cohorts. Results The study included 8400 CCASAnet and 2786 NA-ACCORD patients initiating ART. CCASAnet patients were younger (median 35 vs. 37 years), more likely to be female (27% vs. 20%) and had lower nadir CD4 count (median 148 vs. 195 cells/µL, p<0.001 for all). In multivariable analyses, CCASAnet patients had a higher risk of mortality after ART initiation (adjusted hazard ratio (AHR) 1.61; 95% confidence interval (CI): 1.32 to 1.96), particularly during the first year, but a lower hazard of treatment interruption (AHR: 0.46; 95% CI: 0.42 to 0.50), change to second-line ART (AHR: 0.56; 95% CI: 0.51 to 0.62) and virologic failure (AHR: 0.52; 95% CI: 0.48 to 0.57). Conclusions HIV-positive Latinos initiating ART in Latin America have greater continuity of treatment but are at higher risk of death than Latinos in North America. Factors underlying these differences, such as HIV testing, linkage and access to care, warrant further investigation. PMID:26996992

  8. Health outcomes among HIV-positive Latinos initiating antiretroviral therapy in North America versus Central and South America

    Directory of Open Access Journals (Sweden)

    Carina Cesar

    2016-03-01

    Full Text Available Introduction: Latinos living with HIV in the Americas share a common ethnic and cultural heritage. In North America, Latinos have a relatively high rate of new HIV infections but lower rates of engagement at all stages of the care continuum, whereas in Latin America antiretroviral therapy (ART services continue to expand to meet treatment needs. In this analysis, we compare HIV treatment outcomes between Latinos receiving ART in North America versus Latin America. Methods: HIV-positive adults initiating ART at Caribbean, Central and South America Network for HIV (CCASAnet sites were compared to Latino patients (based on country of origin or ethnic identity starting treatment at North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD sites in the United States and Canada between 2000 and 2011. Cox proportional hazards models compared mortality, treatment interruption, antiretroviral regimen change, virologic failure and loss to follow-up between cohorts. Results: The study included 8400 CCASAnet and 2786 NA-ACCORD patients initiating ART. CCASAnet patients were younger (median 35 vs. 37 years, more likely to be female (27% vs. 20% and had lower nadir CD4 count (median 148 vs. 195 cells/µL, p<0.001 for all. In multivariable analyses, CCASAnet patients had a higher risk of mortality after ART initiation (adjusted hazard ratio (AHR 1.61; 95% confidence interval (CI: 1.32 to 1.96, particularly during the first year, but a lower hazard of treatment interruption (AHR: 0.46; 95% CI: 0.42 to 0.50, change to second-line ART (AHR: 0.56; 95% CI: 0.51 to 0.62 and virologic failure (AHR: 0.52; 95% CI: 0.48 to 0.57. Conclusions: HIV-positive Latinos initiating ART in Latin America have greater continuity of treatment but are at higher risk of death than Latinos in North America. Factors underlying these differences, such as HIV testing, linkage and access to care, warrant further investigation.

  9. Diversity in shortjaw cisco (Coregonus zenithicus) in North America

    Science.gov (United States)

    Todd, T.N.; Steinhilber, M.

    2002-01-01

    Shortjaw cisco (Coregonus zenithicus) exhibit morphological variability across their geographic range in North America and could comprise more than one distinct morph or taxon. To investigate this, principal components analysis was applied to a data set that consisted of four variables from nine localities. All data were obtained from digital images of the specimens and the excised first gill arch. Confidence ellipses (95%) about the means of bivariate distributions of the principal components revealed that some populations were distinct from the others, but a continuity of overlap clouded understanding of pattern among the variation. Most populations had more and longer gillrakers than shortjaw cisco from George Lake (Manitoba) and Basswood Lake (Ontario) that had fewer and shorter gillrakers. This analysis supports the existence of a short- and few-rakered morph and a long- and many-rakered morph. However, most populations of shortjaw cisco from the Great Lakes across Canada to the Arctic share a similar morphology and likely represent a single, widespread species.

  10. Monarch butterfly migration and parasite transmission in eastern North America.

    Science.gov (United States)

    Bartel, Rebecca A; Oberhauser, Karen S; De Roode, Jacobus C; Altizer, Sonia M

    2011-02-01

    Seasonal migration occurs in many animal systems and is likely to influence interactions between animals and their parasites. Here, we focus on monarch butterflies (Danaus plexippus) and a protozoan parasite (Ophryocystis elektroscirrha) to investigate how host migration affects infectious disease processes. Previous work showed that parasite prevalence was lower among migratory than nonmigratory monarch populations; two explanations for this pattern are that (1) migration allows animals to periodically escape contaminated habitats (i.e., migratory escape), and (2) long-distance migration weeds out infected animals (i.e., migratory culling). We combined field-sampling and analysis of citizen science data to examine spatiotemporal trends of parasite prevalence and evaluate evidence for these two mechanisms. Analysis of within-breeding-season variation in eastern North America showed that parasite prevalence increased from early to late in the breeding season, consistent with the hypothesis of migratory escape. Prevalence was also positively related to monarch breeding activity, as indexed by larval density. Among adult monarchs captured at different points along the east coast fall migratory flyway, parasite prevalence declined as monarchs progressed southward, consistent with the hypothesis of migratory culling. Parasite prevalence was also lower among monarchs sampled at two overwintering sites in Mexico than among monarchs sampled during the summer breeding period. Collectively, these results indicate that seasonal migration can affect parasite transmission in wild animal populations, with implications for predicting disease risks for species with threatened migrations. PMID:21618914

  11. Emigrated neuroscientists from Berlin to North America.

    Science.gov (United States)

    Holdorff, Bernd

    2016-01-01

    The highest number of German scholars and physicians, forced by the National Socialist regime to emigrate for "race" or political reasons, were from Berlin. Language and medical exams were requested differently in their new host country-the United States-leading to a concentration of immigrants in the New York and Boston areas. Very early Emergency Committees in Aid of German Scholars and Physicians were established. Undergraduate students (like F. A. Freyhan, H. Lehmann, and H.-L. Teuber) from Berlin seemed to integrate easily, in contrast to colleagues of more advanced age. Some of the former chiefs and senior assistants of Berlin's neurological departments could achieve a successful resettlement (C. E. Benda, E. Haase, C. F. List, and F. Quadfasel) and some a minor degree of success (F. H. Lewy and K. Goldstein). A group of neuropsychiatrists from Bonhoeffer's staff at the Berlin Charité Hospital could rely on the forceful intercession of their former chief. The impact of the émigré colleagues on North American neuroscience is traced in some cases. Apart from the influential field of psychoanalysis, a more diffuse infiltration of German and European neuropsychiatry may be assumed. The contribution to the postwar blossoming of neuropsychology by the émigré neuroscientists K. Goldstein, F. Quadfasel, and H.-L. Teuber is demonstrated in this article.

  12. Emigrated neuroscientists from Berlin to North America.

    Science.gov (United States)

    Holdorff, Bernd

    2016-01-01

    The highest number of German scholars and physicians, forced by the National Socialist regime to emigrate for "race" or political reasons, were from Berlin. Language and medical exams were requested differently in their new host country-the United States-leading to a concentration of immigrants in the New York and Boston areas. Very early Emergency Committees in Aid of German Scholars and Physicians were established. Undergraduate students (like F. A. Freyhan, H. Lehmann, and H.-L. Teuber) from Berlin seemed to integrate easily, in contrast to colleagues of more advanced age. Some of the former chiefs and senior assistants of Berlin's neurological departments could achieve a successful resettlement (C. E. Benda, E. Haase, C. F. List, and F. Quadfasel) and some a minor degree of success (F. H. Lewy and K. Goldstein). A group of neuropsychiatrists from Bonhoeffer's staff at the Berlin Charité Hospital could rely on the forceful intercession of their former chief. The impact of the émigré colleagues on North American neuroscience is traced in some cases. Apart from the influential field of psychoanalysis, a more diffuse infiltration of German and European neuropsychiatry may be assumed. The contribution to the postwar blossoming of neuropsychology by the émigré neuroscientists K. Goldstein, F. Quadfasel, and H.-L. Teuber is demonstrated in this article. PMID:26853762

  13. Geomorphic analysis of transient landscapes in the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American-Caribbean-Cocos plate boundary

    Science.gov (United States)

    Andreani, L.; Gloaguen, R.

    2016-01-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. We intend to characterize and understand the complex tectonic setting that produced an intricate pattern of landscapes using tectonic geomorphology, as well as available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landscapes in northern Central America. We also analyze the drainage network from the Sierra Madre de Chiapas and Maya Mountains in order to extract information about potential vertical displacements. Our results suggest that most of the landscapes of the Sierra Madre de Chiapas and Maya Mountains are in a transient stage. Topographic profiles and morphometric maps highlight elevated relict surfaces that are characterized by a low-amplitude relief. The river longitudinal profiles display upper reaches witnessing these relict landscapes. Lower reaches adjust to new base-level conditions and are characterized by multiple knickpoints. These results backed by published GPS and seismotectonic data allow us to refine and extend existing geodynamic models of the triple junction. Relict landscapes are delimited by faults and thus result from a tectonic control. The topography of the Sierra Madre de Chiapas evolved as the result of (1) the inland migration of deformation related to the coupling between the Chiapas Massif and the Cocos forearc sliver and (2) the compression along the northern tip of the Central American volcanic arc. Although most of the shortening between the Cocos forearc sliver and the North American Plate is accommodated within the Sierra de Chiapas and Sierra de los Cuchumatanes, a small part may be still transmitted to the Maya Mountains and the Belize margin through a "rigid" Petén Basin.

  14. Natural gas pricing and contracting practices in North America

    International Nuclear Information System (INIS)

    Over the past 5 years the natural gas industry in North America has undergone substantial change as a result of the deregulated market. A comparison is provided of the key contract parameters in gas purchase contracts utilized by local distribution companies, industrial customers, cogenerators and marketers. Issues discussed include pricing mechanisms, indexed contracts, negotiated contracts, combinations, dispute resolution, supply, government regulation, industry structures, financial considerations, perception, geological influences, demand, transmission, storage, distribution, price trends and forecasts, Order 636 in the U.S., the evolution of North American market hubs, the futures market, and 'daisy chains' of connecting pipelines. 15 refs., 7 figs., 1 tab

  15. Strangers and neighbours: cross-border banking in North America

    Directory of Open Access Journals (Sweden)

    J.W. DEAN

    2013-12-01

    Full Text Available The paper is concerned with regulatory and competitive aspects of the mutual penetration by Canadian and U.S. banks of each other’s domestic markets. The authors assess the degree to which economic factors alone are responsible for the difference in growth rates between domestic and foreign banks in North America. They argue that regulation has not affected the growth of foreign banks in North America by addressing the question of reciprocity in banking regulations, before examining foreign banks in the U.S. and the manner in which they have been regulated. U.S. banks operating in Canada are then dealt with. Finally, the results of an empirical test of the proposition that the growth of cross-border banking is attributable to factors other than differential regulation is presented.

  16. Book review: Shorebirds of North America: the photographic guide

    Science.gov (United States)

    Peterjohn, Bruce G.

    2005-01-01

    As stated in the preface of this new guide, shorebirds are among our most engaging birds. Their ecology and behavior are the subjects of numerous ornithological studies, their identification can challenge the skills of the most serious birdwatchers, and people with a casual interest in birds are captivated by the antics of Sanderlings (Calidris alba) chasing waves along a beach. While some books provide a worldwide perspective on shorebird identification, this book is the first guide devoted solely to identifying every species occurring in North America. Its coverage is truly continental, extending from Alaska to Panama and including the West Indies.Review info: Shorebirds of North America: the photographic guide. By Dennis R. Paulson, 2005. ISBN: 0691102740, 384 pp.

  17. Social Pedagogy in North America: historical background and current developments

    Directory of Open Access Journals (Sweden)

    Daniel Schugurensky

    2015-12-01

    Full Text Available In North America, the use of the term ‘social pedagogy’ is a relatively new phenomenon, but social pedagogical practices have been used for a long time. The recent interest in the field of social pedagogy can be explained in part by the publication of an unprecedented volume of books and articles in English language, the creation of a new international journal, the simultaneous development of graduate programs in social pedagogy in the UK and the USA, and the establishment of a social pedagogy association that brings together academics and practitioners. In North America, social pedagogy thinking is influenced by the history of the field, by current social pedagogy theory and practice in other parts of the world, and by several traditions that connect education with social change. The paper discusses ten of them: indigenous education, progressive education, social movement learning, community development, public pedagogy, popular education, participatory action research, social economy, participatory democracy, and critical theory. 

  18. Phylogeography of infectious haematopoietic necrosis virus in North America

    DEFF Research Database (Denmark)

    Kurath, G.; Garver, K.A.; Troyer, R.M.;

    2003-01-01

    Infectious hematopoietic necrosis virus (IHNV) is a rhabdoviral pathogen that infects wild and cultured salmonid fish throughout the Pacific Northwest of North America. IHNV causes severe epidemics in young fish and can cause disease or occur asymptomatically in adults. In a broad survey of 323 I...... influencing IHNV evolution may have included ocean migration ranges of their salmonid host populations and anthropogenic effects associated with fish culture....

  19. Oral Rabies Vaccination in North America: Opportunities, Complexities, and Challenges

    OpenAIRE

    Dennis Slate; Timothy P Algeo; Kathleen M Nelson; Chipman, Richard B.; Dennis Donovan; Blanton, Jesse D.; Michael Niezgoda; Rupprecht, Charles E.

    2009-01-01

    Steps to facilitate inter-jurisdictional collaboration nationally and continentally have been critical for implementing and conducting coordinated wildlife rabies management programs that rely heavily on oral rabies vaccination (ORV). Formation of a national rabies management team has been pivotal for coordinated ORV programs in the United States of America. The signing of the North American Rabies Management Plan extended a collaborative framework for coordination of surveillance, control, a...

  20. Aridland Springs in North America: Ecology and Conservation

    Directory of Open Access Journals (Sweden)

    Kate Smith

    2012-03-01

    Full Text Available Review of Aridland Springs in North America: Ecology and Conservation. Lawrence E. Stevens and Vicky J. Meretsky, editors. 2008. The University of Arizona Press and the Arizona‐SonoraDesert Museum, Tucson.Pp. 406, 4 black‐and‐white photos, 28 illustrations, 38 tables, 8 maps, bibliography.$75.00 (cloth. ISBN 978‐0‐8165‐2645‐1.

  1. A refugee's perspective on their neurosurgical care in North America

    OpenAIRE

    C Michael Honey; Anujan Poologaindran; Maureen Mayhew; Laura Vander Steen; Christopher Charles Gillis

    2015-01-01

    Background: There is a growing population of refugees within North America and an increasing awareness of their unique medical requirements. These requirements include both a well-recognized need to understand the different pathologies that can present in these patients as well as the rarely described need to understand their unique perspective and how this can impact their medical care, especially for routine neurosurgical conditions. This paper highlights a refugee′s perspective toward the ...

  2. North America: Multiplying media in a dynamic landscape

    OpenAIRE

    Eid, Mahmoud; Buchanan, Carrie

    2005-01-01

    Perhaps no region on earth has been as affected by the dramatic pace and extent of media development since 1990 as North America, where most have ready access to new media, such as the Internet and the latest telecommunications devices, as well as the traditional newspapers, radio and television. Even traditional media have undergone profound change as convergence and cross–ownership brought them together in vast media conglomerates dominated by a handful of global corporations. Digitization ...

  3. US of tissue banking and transplantation in North America

    International Nuclear Information System (INIS)

    Tissue banking in North America began as surgical bone banking in individual hospitals and progressed to recovery of cadaveric tissues, initially by the United States Navy Tissue Bank and more recently to regional tissue banks throughout North America. The American Association of Tissue Banks was established in 1976 to develop standards for tissue banking and the eventual inspection and accreditation of tissue banks. The gathering of statistics of tissue banking practices was first undertaken in 1992, from accredited tissue banks. The most recent statistics were compiled in 1997 and will be reported at this conference.There are currently 63 accredited tissue banks in North America, 60 in the United States and three in Canada. Overall, tissue donation has increased by 48% during this 5 year reporting time. During the same period, the number of living surgical bone donors has decreased from nearly 3,000 to less than 500. This impact is largely due to the new regulations that have been implemented by the Food and Drug Administration (FDA). There were over 340,000 bone grafts distributed in 1996, an increase of 20% over 1992, 33% were not sterilized, 21% were sterilized using irradiation, and 45% were demineralized. Only 1% were processed using ethylene oxide as a sterilant, a decrease from 15% in 1992. The primary mode of preservation and storage is freeze-drying with 90% of the tissues falling into this category and the rest being frozen. The second largest number of grafts distributed were skin grafts. Total tissue grafts distributed including cornea was 445,417. In January 1998, the FDA Final Rule regarding regulation of tissue banking became effective. The elements of that Final Rule and new tissue banking rules the FDA has proposed will be discussed along with regulations recently published by the Health and Human Services Department relative to organ and tissue donor referrals. Tissue Banking in North America continues to evolve and has become more and more

  4. Clinical characteristics of Takotsubo cardiomyopathy in North America

    OpenAIRE

    Saeed Ahmed; Patompong Ungprasert; Supawat Ratanapo; Tanveer Hussain; Riesenfeld, Erik P.

    2013-01-01

    Background: Takotsubo cardiomyopathy (TC) or transient left ventricular apical ballooning syndrome is an acute cardiac syndrome characterized by transient wall motion abnormalities extending beyond a single epicardial vessel in the absence of significant obstructive coronary artery disease. Aim: This study was to describe the clinical characteristics of TC in North America. Materials and Methods: We identified 10 patients who met the Mayo Clinic criteria for TC using our Electronic Medical Re...

  5. Recent Rates of Forest Harvest and Conversion in North America

    Science.gov (United States)

    Masek, Jeffrey G.; Cohen, Warren B.; Leckie, Donald; Wulder, Michael A.; Vargas, Rodrigo; de Jong, Ben; Healey, Sean; Law, Beverly; Birdsey, Richard; Houghton, R. A.; Mildrexler, David; Goward, Samuel; Smith, W. Brad

    2011-01-01

    Incorporating ecological disturbance into biogeochemical models is critical for estimating current and future carbon stocks and fluxes. In particular, anthropogenic disturbances, such as forest conversion and wood harvest, strongly affect forest carbon dynamics within North America. This paper summarizes recent (2000.2008) rates of extraction, including both conversion and harvest, derived from national forest inventories for North America (the United States, Canada, and Mexico). During the 2000s, 6.1 million ha/yr were affected by harvest, another 1.0 million ha/yr were converted to other land uses through gross deforestation, and 0.4 million ha/yr were degraded. Thus about 1.0% of North America fs forests experienced some form of anthropogenic disturbance each year. However, due to harvest recovery, afforestation, and reforestation, the total forest area on the continent has been roughly stable during the decade. On average, about 110 m3 of roundwood volume was extracted per hectare harvested across the continent. Patterns of extraction vary among the three countries, with U.S. and Canadian activity dominated by partial and clear ]cut harvest, respectively, and activity in Mexico dominated by conversion (deforestation) for agriculture. Temporal trends in harvest and clearing may be affected by economic variables, technology, and forest policy decisions. While overall rates of extraction appear fairly stable in all three countries since the 1980s, harvest within the United States has shifted toward the southern United States and away from the Pacific Northwest.

  6. Uranium provinces of North America; their definition, distribution, and models

    Science.gov (United States)

    Finch, Warren Irvin

    1996-01-01

    Uranium resources in North America are principally in unconformity-related, quartz-pebble conglomerate, sandstone, volcanic, and phosphorite types of uranium deposits. Most are concentrated in separate, well-defined metallogenic provinces. Proterozoic quartz-pebble conglomerate and unconformity-related deposits are, respectively, in the Blind River?Elliot Lake (BRELUP) and the Athabasca Basin (ABUP) Uranium Provinces in Canada. Sandstone uranium deposits are of two principal subtypes, tabular and roll-front. Tabular sandstone uranium deposits are mainly in upper Paleozoic and Mesozoic rocks in the Colorado Plateau Uranium Province (CPUP). Roll-front sandstone uranium deposits are in Tertiary rocks of the Rocky Mountain and Intermontane Basins Uranium Province (RMIBUP), and in a narrow belt of Tertiary rocks that form the Gulf Coastal Uranium Province (GCUP) in south Texas and adjacent Mexico. Volcanic uranium deposits are concentrated in the Basin and Range Uranium Province (BRUP) stretching from the McDermitt caldera at the Oregon-Nevada border through the Marysvale district of Utah and Date Creek Basin in Arizona and south into the Sierra de Pe?a Blanca District, Chihuahua, Mexico. Uraniferous phosphorite occurs in Tertiary sediments in Florida, Georgia, and North and South Carolina and in the Lower Permian Phosphoria Formation in Idaho and adjacent States, but only in Florida has economic recovery been successful. The Florida Phosphorite Uranium Province (FPUP) has yielded large quantities of uranium as a byproduct of the production of phosphoric acid fertilizer. Economically recoverable quantities of copper, gold, molybdenum, nickel, silver, thorium, and vanadium occur with the uranium deposits in some provinces. Many major epochs of uranium mineralization occurred in North America. In the BRELUP, uranium minerals were concentrated in placers during the Early Proterozoic (2,500?2,250 Ma). In the ABUP, the unconformity-related deposits were most likely formed

  7. A revised estimate of Pacific-North America motion and implications for Western North America plate boundary zone tectonics

    Science.gov (United States)

    Demets, Charles; Gordon, Richard G.; Stein, Seth; Argus, Donald F.

    1987-01-01

    Marine magnetic profiles from the Gulf of Californa are studied in order to revise the estimate of Pacific-North America motion. It is found that since 3 Ma spreading has averaged 48 mm/yr, consistent with a new global plate motion model derived without any data. The present data suggest that strike-slip motion on faults west of the San Andreas is less than previously thought, reducing the San Andreas discrepancy with geodetic, seismological, and other geologic observations.

  8. Population size of snowy plovers breeding in North America

    Science.gov (United States)

    Thomas, Susan M.; Lyons, James E.; Andres, Brad A.; T-Smith, Elise Elliot; Palacios, Eduardo; Cavitt, John F.; Royle, J. Andrew; Fellows, Suzanne D.; Maty, Kendra; Howe, William H.; Mellink, Eric; Melvin, Stefani; Zimmerman, Tara

    2012-01-01

    Snowy Plovers (Charadrius nivosus) may be one of the rarest shorebirds in North America yet a comprehensive assessment of their abundance and distribution has not been completed. During 2007 and 2008, 557 discrete wetlands were surveyed and nine additional large wetland complexes sampled in México and the USA. From these surveys, a population of 23,555 (95% CI = 17,299 – 29,859) breeding Snowy Plovers was estimated. Combining the estimate with information from areas not surveyed, the total North American population was assessed at 25,869 (95% CI = 18,917 – 32,173). Approximately 42% of all breeding Snowy Plovers in North America resided at two sites (Great Salt Lake, Utah, and Salt Plains National Wildlife Refuge, Oklahoma), and 33% of all these were on wetlands in the Great Basin (including Great Salt Lake). Also, coastal habitats in central and southern Texas supported large numbers of breeding plovers. New breeding sites were discovered in interior deserts and highlands and along the Pacific coast of México; approximately 9% of the North American breeding population occurred in México. Because of uncertainties about effects of climate change and current stresses to breeding habitats, the species should be a management and conservation priority. Periodic monitoring should be undertaken at important sites to ensure high quality habitat is available to support the Snowy Plover population.

  9. Aphasia centers in North America: a survey.

    Science.gov (United States)

    Simmons-Mackie, Nina; Holland, Audrey L

    2011-08-01

    There is a growing trend toward dedicated programs designed to improve the lives of people with aphasia and their families. We are referring to these programs collectively as "aphasia centers." These programs purportedly differ from more traditional medically based aphasia rehabilitation. However, there is no directory of aphasia centers and no definition of what constitutes such a program. Therefore, an online survey was designed to identify and describe aphasia centers in the United States and Canada. A 37-question survey was posted online via SurveyMonkey. An introductory letter was distributed by electronic mail to a listserv and mailing lists of programs associated with aphasia. Potential respondents who considered themselves an aphasia center were asked to complete the survey. A total of 33 survey responses were analyzed, and descriptive data were compiled resulting in a description of the following aspects of aphasia centers: demographic information, mission, admission and discharge policies, assessment practices, program logistics, staffing patterns, marketing, funding, and services offered. In addition, a qualitative analysis of written text responses revealed the following key themes that appear to characterize the responding programs: services that differ from traditional aphasia rehabilitation; a sense of community; a holistic focus on quality of life, psychosocial well-being, participation, and social support; the centrality of group interaction; and variety/intensity of services. PMID:21968557

  10. 75 FR 51846 - BlueScope Buildings North America Including Workers Whose Unemployment Insurance (UI) Wages Are...

    Science.gov (United States)

    2010-08-23

    ...Scope Buildings North America had their wages reported through a separate unemployment insurance (UI... America, including workers whose unemployment insurance (UI) wages are reported through Buttler... Employment and Training Administration BlueScope Buildings North America Including Workers Whose...

  11. Terrane Stations: intra-oceanic subduction assembled western North America

    Science.gov (United States)

    Sigloch, K.; Mihalynuk, M. G.

    2012-12-01

    The western quarter of North America consists of accreted terranes, crustal blocks that were added to the margin in a series of collisions over the past 200 million years - but why? The most widely accepted explanation posits a scenario analogous to Andean subduction, with these terranes conveyed to the continental margin while the oceanic Farallon plate subducted under it. Yet purely Andean-style subduction under North America is questionable as a terrane delivery mechanism, since no comparable accretion sequence took place along the South American margin, and since North American terranes are of very varied provenance. We consider this geological question directly related to a geodynamical one: Why has it been so difficult to reconcile - even on the largest scale - the geometries and locations of slabs in the lower-mantle, as imaged by seismic tomography, with Cretaceous plate reconstructions of the North American west coast (unless anomalous mantle rheology or ad hoc shifts of absolute reference frame are invoked)? This problem was recognized soon after the discovery of the massive, lower-mantle "Farallon slabs" by Grand (1994), but has recently been aggravated by the discovery of additional, more westerly deep slabs (Sigloch et al. 2008), thanks to USArray. Not all of these slabs can be Farallon, unless very non-vertical and/or uneven slab sinking behavior is allowed for. As a joint solution, we offer a radical reinterpretation of paleogeography and test it quantitatively: The seas west of Cretaceous North America must have resembled today's western Pacific. The Farallon and two more plates subducted into the intra-oceanic trenches of a vast archipelago in the eastern Panthalassa (proto-Pacific) ocean, both from the east and the west. The trenches remained stationary throughout much of Jurassic and Cretaceous times, depositing the massive, near-vertical slab walls imaged in the lower mantle today. On their overriding plates, island arcs and subduction complexes

  12. North America carbon dioxide sources and sinks: magnitude, attribution, and uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    King, Anthony W.; Hayes, Daniel J.; Huntzinger, Deborah N.; West, Tristram O.; Post, W. M.

    2012-12-01

    North America is both a source and sink of atmospheric CO2. Sources, predominately fossil-fuel combustion in the United States along with contributions from deforestation in Mexico, add CO2 to the atmosphere. Most North America ecosystems, particularly regrowing forests in the United States, are sinks for atmospheric CO2. CO2 is removed from the atmosphere in photosynthesis, converted into biomass and stored as carbon in vegetation, soil and wood products. Fossil-fuel emissions dominate the North American source-sink balance. North America is a net source of atmospheric CO2 with ecosystem sinks balancing approximately 35% of fossil-fuel CO2 emissions from North America.

  13. Causes of decadal climate variability over the North Pacific and North America

    International Nuclear Information System (INIS)

    The cause of decadal climate variability over the North Pacific and North America is investigated by analyzing data from a multi-decadal integration with a state of the art coupled ocean-atmosphere model and observations. About one third of the low-frequency climate variability in the region of interest can be attributed to a cycle involving unstable air-sea interactions between the subtropical gyre circulation in the North Pacific and the Aleutian low pressure system. The existence of this cycle provides a basis for long-range climate forecasting over the western United States at decadal time scales. (orig.)

  14. Echinococcus multilocularis in North America: the great unknown

    Directory of Open Access Journals (Sweden)

    Massolo Alessandro

    2014-01-01

    Full Text Available Over the last decade, studies have begun to shed light on the distribution and genetic characterization of Echinococcus multilocularis, the causative agent of alveolar echinococcosis (AE, in North America. Recent findings indicate that the parasite is likely expanding its range in the central region of the United States and Canada and that invasions of European strains might have occurred. In our review, we present the available data on E. multilocularis infections in wild and domestic animals and humans in North America and emphasize the lack of knowledge on the distribution of the parasite in wild and domestic hosts. Furthermore, we stress the need to better understand the complexity of host communities and their roles in shaping the transmission and distribution of the parasite. We hypothesize that a lack of knowledge about AE by North American physicians might result in the misdiagnosis of cases and an underestimation of disease incidence. The endemic presence of the parasite in urban areas and a recent human case in Alberta, Canada, suggest that the scientific community may need to reconsider the local public health risks, re-assess past cases that might have been overlooked and increase surveillance efforts to identify new cases of human AE.

  15. Automotive Mg Research and Development in North America

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, Joseph A. [U.S. Department of Energy; Jackman, Jennifer [CANMET - Materials Technology Laboratory, Natural Resources of Canada; Li, Naiyi [Ford Motor Company; Osborne, Richard J. [General Motors Corporation; Powell, Bob R. [General Motors Corporation; Sklad, Philip S [ORNL

    2006-01-01

    Expanding world economic prosperity and probable peaking of conventional petroleum production in the coming decades require efforts to increase the efficiency of, and the development of alternatives to, petroleum-based fuels used in automotive transportation. North America has been aggressively pursuing both approaches for over ten years. Mainly as a result of lower prices due to global sourcing, magnesium has recently emerged as a serious candidate for lightweighting, and thus increasing the fuel efficiency of, automotive transportation. Automotive vehicles produced in North America currently use more Mg than vehicles produced elsewhere in the world, but the amounts per vehicle are very small in comparison to other materials such as steel, aluminum and plastics. The reasons, besides price, are primarily a less-developed state of technology for Mg in automotive transportation applications and lack of familiarity by the vehicle manufacturers with the material. This paper reviews some publicly-known, recent, present and future North American research and development activities in Mg for automotive applications.

  16. Catalogue of Geadephaga (Coleoptera: Adephaga of America, north of Mexico

    Directory of Open Access Journals (Sweden)

    Yves Bousquet

    2012-11-01

    Full Text Available All scientific names of Trachypachidae, Rhysodidae, and Carabidae (including cicindelines recorded from America north of Mexico are catalogued. Available species-group names are listed in their original combinations with the author(s, year of publication, page citation, type locality, location of the name-bearing type, and etymology for many patronymic names. In addition, the reference in which a given species-group name is first synonymized is recorded for invalid taxa. Genus-group names are listed with the author(s, year of publication, page citation, type species with way of fixation, and etymology for most. The reference in which a given genus-group name is first synonymized is recorded for many invalid taxa. Family-group names are listed with the author(s, year of publication, page citation, and type genus. The geographical distribution of all species-group taxa is briefly summarized and their state and province records are indicated.One new genus-group taxon, Randallius new subgenus (type species: Chlaenius purpuricollis Randall, 1838, one new replacement name, Pterostichus amadeus new name for Pterostichus vexatus Bousquet, 1985, and three changes in precedence, Ellipsoptera rubicunda (Harris, 1911 for Ellipsoptera marutha (Dow, 1911, Badister micans LeConte, 1844 for Badister ocularis Casey, 1920, and Agonum deplanatum Ménétriés, 1843 for Agonum fallianum (Leng, 1919, are proposed. Five new genus-group synonymies and 65 new species-group synonymies, one new species-group status, and 12 new combinations (see Appendix 5 are established.The work also includes a discussion of the notable private North American carabid collections, a synopsis of all extant world geadephagan tribes and subfamilies, a brief faunistic assessment of the fauna, a list of valid species-group taxa, a list of North American fossil Geadephaga (Appendix 1, a list of North American Geadephaga larvae described or illustrated (Appendix 2, a list of Geadephaga species

  17. 77 FR 62535 - Hydro Aluminum North America, Inc., Midwest Region, Including On-Site Leased Workers From...

    Science.gov (United States)

    2012-10-15

    ... Employment and Training Administration Hydro Aluminum North America, Inc., Midwest Region, Including On- Site Leased Workers From Employment Group, Aerotek, and Manpower, Kalamazoo, Michigan; Hydro Aluminum North... and former workers of Hydro Aluminum North America, Inc., Kalamazoo, Michigan. The subject...

  18. North-South precipitation patterns in western North America on interannual-to-decadal timescales

    Science.gov (United States)

    Dettinger, M.D.; Cayan, D.R.; Diaz, Henry F.; Meko, D.M.

    1998-01-01

    The overall amount of precipitation deposited along the West Coast and western cordillera of North America from 25??to 55??N varies from year to year, and superimposed on this domain-average variability are varying north-south contrasts on timescales from at least interannual to interdecadal. In order to better understand the north-south precipitation contrasts, their interannual and decadal variations are studied in terms of how much they affect overall precipitation amounts and how they are related to large-scale climatic patterns. Spatial empirical orthogonal functions (EOFs) and spatial moments (domain average, central latitude, and latitudinal spread) of zonally averaged precipitation anomalies along the westernmost parts of North America are analyzed, and each is correlated with global sea level pressure (SLP) and sea surface temperature series, on interannual (defined here as 3-7 yr) and decadal (>7 yr) timescales. The interannual band considered here corresponds to timescales that are particularly strong in tropical climate variations and thus is expected to contain much precipitation variability that is related to El Nino-Southern Oscillation; the decadal scale is defined so as to capture the whole range of long-term climatic variations affecting western North America. Zonal EOFs of the interannual and decadal filtered versions of the zonal-precipitation series are remarkably similar. At both timescales, two leading EOFs describe 1) a north-south seesaw of precipitation pivoting near 40??N and 2) variations in precipitation near 40??N, respectively. The amount of overall precipitation variability is only about 10% of the mean and is largely determined by precipitation variations around 40??-45??N and most consistently influenced by nearby circulation patterns; in this sense, domain-average precipitation is closely related to the second EOF. The central latitude and latitudinal spread of precipitation distributions are strongly influenced by precipitation

  19. 75 FR 52981 - Bluescope Buildings North America, Including Workers Whose Unemployment Insurance (UI) Wages Are...

    Science.gov (United States)

    2010-08-30

    ... Unemployment Insurance (UI) Wages Are Reported Through Butler Manufacturing Company, Laurinburg, NC; Amended...Scope Buildings North America had their wages reported through a separate unemployment insurance (UI... America, including workers whose unemployment insurance (UI) wages are reported through...

  20. Renewable energy in North America: Moving toward a richer mix

    Energy Technology Data Exchange (ETDEWEB)

    Cobey, Cathy

    2010-09-15

    A follow-up to our January study with Economist Intelligence Unit, Renewable energy in North America. The update will further our call to action for a concerted group effort by energy suppliers, corporate consumers and government. 1. Introduction - State of the industry, progress made to replace carbon-based fossil fuels with alternative energy - Barriers - Pressure from public and government 2. Recent progress - Examine existing government incentive programs - International commitments - Examine the role of energy suppliers, corporate consumers and government 3. Call to Action - Creating an environment that encourages both supply and demand of renewable energy.

  1. Borderlands : Comparing Border Security in North America and Europe

    OpenAIRE

    Brunet-Jailly, Emmanuel

    2007-01-01

    Border security has been high on public-policy agendas in Europe and North America since the September 11, 2001 attacks on the World Trade Centre in New York City and on the headquarters of the American military in Washington DC. Governments are now confronted with managing secure borders, a policy objective that in this era of increased free trade and globalization must compete with intense cross-border flows of people and goods. Border-security policies must enable security personnel to ide...

  2. PAGES-Powell North America 2k database

    Science.gov (United States)

    McKay, N.

    2014-12-01

    Syntheses of paleoclimate data in North America are essential for understanding long-term spatiotemporal variability in climate and for properly assessing risk on decadal and longer timescales. Existing reconstructions of the past 2,000 years rely almost exclusively on tree-ring records, which can underestimate low-frequency variability and rarely extend beyond the last millennium. Meanwhile, many records from the full spectrum of paleoclimate archives are available and hold the potential of enhancing our understanding of past climate across North America over the past 2000 years. The second phase of the Past Global Changes (PAGES) North America 2k project began in 2014, with a primary goal of assembling these disparate paleoclimate records into a unified database. This effort is currently supported by the USGS Powell Center together with PAGES. Its success requires grassroots support from the community of researchers developing and interpreting paleoclimatic evidence relevant to the past 2000 years. Most likely, fewer than half of the published records appropriate for this database are publicly archived, and far fewer include the data needed to quantify geochronologic uncertainty, or to concisely describe how best to interpret the data in context of a large-scale paleoclimatic synthesis. The current version of the database includes records that (1) have been published in a peer-reviewed journal (including evidence of the record's relationship to climate), (2) cover a substantial portion of the past 2000 yr (>300 yr for annual records, >500 yr for lower frequency records) at relatively high resolution (<50 yr/observation), and (3) have reasonably small and quantifiable age uncertainty. Presently, the database includes records from boreholes, ice cores, lake and marine sediments, speleothems, and tree rings. This poster presentation will display the site locations and basic metadata of the records currently in the database. We invite anyone with interest in

  3. Bat white-nose syndrome in North America

    Science.gov (United States)

    Blehert, David S.; Lorch, Jeffrey M.; Ballmann, Anne E.; Cryan, Paul M.; Meteyer, Carol U.

    2011-01-01

    * The newly described fungus, Geomyces destructans, causes an invasive skin infection in bats and is the likely agent of white-nose syndrome (WNS). * With immune system functions and body temperatures reduced during hibernation, bats may be unusually susceptible to a pathogenic fungus such as G. destructans. * WNS was first observed in a popular show cave near Albany, New York, leading some investigators to suspect that a visitor inadvertently introduced G. destructans at this site, triggering a wider WNS outbreak in North America. * Biologists trying to manage WNS within North American bat populations face major challenges, including the variety of susceptible host species, incredible dispersal capabilities of bats, difficulties in treating such populations, and persistence of the pathogen in their vulnerable underground habitats.

  4. Rapid Middle Eocene temperature change in western North America

    Science.gov (United States)

    Methner, Katharina; Mulch, Andreas; Fiebig, Jens; Wacker, Ulrike; Gerdes, Axel; Graham, Stephan A.; Chamberlain, C. Page

    2016-09-01

    Eocene hyperthermals are among the most enigmatic phenomena of Cenozoic climate dynamics. These hyperthermals represent temperature extremes superimposed on an already warm Eocene climate and dramatically affected the marine and terrestrial biosphere, yet our knowledge of temperature and rainfall in continental interiors is still rather limited. We present stable isotope (δ18O) and clumped isotope temperature (Δ47) records from a middle Eocene (41 to 40 Ma) high-elevation mammal fossil locality in the North American continental interior (Montana, USA). Δ47 paleotemperatures of soil carbonates delineate a rapid +9/-11 °C temperature excursion in the paleosol record. Δ47 temperatures progressively increase from 23 °C ± 3 °C to peak temperatures of 32 °C ± 3 °C and subsequently drop by 11 °C. This hyperthermal event in the middle Eocene is accompanied by low δ18O values and reduced pedogenic carbonate concentrations in paleosols. Based on laser ablation U/Pb geochronology of paleosol carbonates in combination with magnetostratigraphy, biostratigraphy, stable isotope, and Δ47 evidence, we suggest that this pronounced warming event reflects the Middle Eocene Climatic Optimum (MECO) in western North America. The terrestrial expression of northern hemisphere MECO in western North America appears to be characterized by warmer and wetter (sub-humid) conditions, compared to the post-MECO phase. Large and rapid shifts in δ18O values of precipitation and pedogenic CaCO3 contents parallel temperature changes, indicating the profound impact of the MECO on atmospheric circulation and rainfall patterns in the western North American continental interior during this transient warming event.

  5. Retrospective analysis of organophosphate flame retardants in herring gull eggs and relation to the aquatic food web in the Laurentian Great Lakes of North America.

    Science.gov (United States)

    Greaves, Alana K; Letcher, Robert J; Chen, Da; McGoldrick, Daryl J; Gauthier, Lewis T; Backus, Sean M

    2016-10-01

    With the phase-out and regulation of some flame retardant chemicals, the production and usage of organophosphate triester flame retardants (OPFRs) has increased in recent years. In the present study, 14 OPFRs (either chlorinated, brominated or non-halogenated) were analyzed in egg pools of 10-13 individual herring gull eggs from five colonial nesting sites for 11 years spanning 1990-2010, (for a total of n=55 egg pools) in the Laurentian Great Lakes of North America (Chantry Island, Fighting Island, Agawa Rocks, Toronto Harbour and Gull Island). OPFR profiles varied slightly between colony sites and collection years. For all five sites tris(2-chloroisopropyl) phosphate (TCIPP), tris(2-chloroethyl) phosphate (TCEP) and tris(2-butoxyethyl) phosphate (TBOEP) were detected, while triphenyl phosphate (TPHP) was only quantifiable in eggs from Chantry Island and Gull Island collected in 2008 and 2010. For the 2010 egg pools, the ΣOPFR concentrations were generally low and ranged from 2.02 to 6.69 ng/g wet weight (ww). ΣOPFR concentrations in 2010 were significantly higher (pgull fish prey) and lake trout from western Lake Erie and Ontario, only contained TBOEP at low to sub ng/g ww concentrations. These results demonstrate that low to sub-ppb concentrations of at least three OPFRs, TCIPP, TCEP and TBOEP, have been persistent in herring gull eggs from the Great Lakes for at least the past 20 years, probably bioaccumulate mainly via the fish diet, and are transferred to the eggs of exposed herring gulls. PMID:27322497

  6. Preadaptation and post-introduction evolution facilitate the invasion of Phragmites australis in North America

    Science.gov (United States)

    Guo, Wen-Yong; Lambertini, Carla; Nguyen, Loc Xuan; Li, Xiu-Zhen; Brix, Hans

    2014-01-01

    Compared with non-invasive species, invasive plant species may benefit from certain advantageous traits, for example, higher photosynthesis capacity and resource/energy-use efficiency. These traits can be preadapted prior to introduction, but can also be acquired through evolution following introduction to the new range. Disentangling the origins of these advantageous traits is a fundamental and emerging question in invasion ecology. We conducted a multiple comparative experiment under identical environmental condition with the invasive haplotype M lineage of the wetland grass Phragmites australis and compared the ecophysiological traits of this invasive haplotype M in North America with those of the European ancestor and the conspecific North American native haplotype E lineage, P. australis ssp. americanus. The invasive haplotype M differed significantly from the native North American conspecific haplotype E in several ecophysiological and morphological traits, and the European haplotype M had a more efficient photosynthetic apparatus than the native North American P. australis ssp. americanus. Within the haplotype M lineage, the introduced North American P. australis exhibited different biomass allocation patterns and resource/energy-use strategies compared to its European ancestor group. A discriminant analysis of principal components separated the haplotype M and the haplotype E lineages completely along the first canonical axis, highly related to photosynthetic gas-exchange parameters, photosynthetic energy-use efficiency and payback time. The second canonical axis, highly related to photosynthetic nitrogen use efficiency and construction costs, significantly separated the introduced P. australis in North America from its European ancestor. Synthesis. We conclude that the European P. australis lineage was preadapted to be invasive prior to its introduction, and that the invasion in North America is further stimulated by rapid post-introduction evolution in

  7. Drought-induced vegetation stress in southwestern North America

    International Nuclear Information System (INIS)

    Trends towards earlier greenup and increased average greenness have been widely reported in both humid and dry ecosystems. By analyzing NOAA (National Oceanic and Atmospheric Administration) AVHRR (Advanced Very High Resolution Radiometer) data from 1982 to 2007, we report complex trends in both the growing season amplitude and seasonally integrated vegetation greenness in southwestern North America and further highlight regions consistently experiencing drought stress. In particular, greenness measurements from 1982 to 2007 show an increasing trend in grasslands but a decreasing trend in shrublands. However, vegetation greenness in this period has experienced a strong cycle, increasing from 1982 to 1993 but decreasing from 1993 to 2007. The significant decrease during the last decade has reduced vegetation greenness by 6% in shrublands and 13% in grasslands (16% and 21%, respectively, in the severe drought years). The greenness cycle correlates to both annual precipitation and dry season length derived from NOAA North America Regional Reanalysis data. If drought events continue as predicted by climate models, they will exacerbate ecosystem degradation and reduce carbon uptake.

  8. Mental Health Problems in Primary Care: Progress in North America

    Directory of Open Access Journals (Sweden)

    Kathryn M. Magruder

    2007-03-01

    Full Text Available Background and Objectives: Research in the last decade has acknowledged that primary care plays a pivotal role in the delivery of mental health services. The aim of this paper is to review major accomplishments, emerging trends, and continuing gaps concerning mental health problems in primary care in North America. Methods: Literature from North America was reviewed and synthesized. Results: Major accomplishments include: the development and adoption of a number of clinical guidelines specifically for mental health conditions in primary care, the acceptance of the chronic care model as a framework for treating depression in primary care, and the clear adoption of pharmacologic approaches as the predominant mode for treating depression and anxiety. Emerging trends include: the use of non-physician facilitators as care managers in the treatment of depression in primary care, increasing use of technology in the assessment and treatment of mental health conditions in primary care, and dissemination and implementation of integrated mental health treatment approaches. Lingering issues include: the difficulty in moving beyond problem identification and initiation of treatment to sustaining evidence-based treatments, agreement on a common metric to evaluate outcomes, and the stigma still associated with mental illness. Conclusion: Though there now exists a solid and growing evidence base for the delivery of mental health services in primary care, there are still significant challenges which must be overcome in order to make further advances.

  9. Conservation of native Pacific trout diversity in western North America

    Science.gov (United States)

    Penaluna, Brooke E.; Abadía-Cardoso, Alicia; Dunham, Jason; García de León, Francisco J; Gresswell, Robert E.; Luna, Arturo Ruiz; Taylor, Eric B.; Shepard, Bradley B.; Al-Chokhachy, Robert K.; Muhlfeld, Clint C.; Bestgen, Kevin R.; Rogers, Kevin H.; Escalante, Marco A; Keeley, Ernest R; Temple, Gabriel; Williams, Jack E.; Matthews, Kathleen; Pierce, Ron; Mayden, Richard L.; Kovach, Ryan; Garza, John Carlos; Fausch, Kurt D.

    2016-01-01

    Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review the state of knowledge on these important issues, focusing on Pacific trout in the genus Oncorhynchus. Although most research on salmonid fishes emphasizes Pacific salmon, we focus on Pacific trout because they share a common evolutionary history, and many taxa in western North America have not been formally described, particularly in the southern extent of their ranges. Research in recent decades has led to the revision of many hypotheses concerning the origin and diversification of Pacific trout throughout their range. Although there has been significant success at addressing past threats to Pacific trout, contemporary and future threats represented by nonnative species, land and water use activities, and climate change pose challenges and uncertainties. Ultimately, conservation of Pacific trout depends on how well these issues are understood and addressed, and on solutions that allow these species to coexist with a growing scope of human influences.

  10. Parasites of freshwater fishes in North America: why so neglected?

    Science.gov (United States)

    Scholz, Tomáš; Choudhury, Anindo

    2014-02-01

    Fish parasitology has a long tradition in North America and numerous parasitologists have contributed considerably to the current knowledge of the diversity and biology of protistan and metazoan parasites of freshwater fishes. The Journal of Parasitology has been essential in disseminating this knowledge and remains a significant contributor to our understanding of fish parasites in North America as well as more broadly at the international level. However, with a few exceptions, the importance of fish parasites has decreased during the last decades, which is reflected in the considerable decline of funding and corresponding decrease of attention paid to these parasites in Canada and the United States of America. After the 'golden age' in the second half of the 20th Century, fish parasitology in Canada and the United States went in a new direction, driven by technology and a shift in priorities. In contrast, fish parasitology in Mexico has undergone rapid development since the early 1990s, partly due to extensive international collaboration and governmental funding. A critical review of the current data on the parasites of freshwater fishes in North America has revealed considerable gaps in the knowledge of their species composition, host specificity, life cycles, evolution, phylogeography, and relationships with their fish hosts. As to the key question, "Why so neglected?" this is probably because: (1) fish parasites are not in the forefront due to their lesser economic importance; (2) there is little funding for this kind of research, especially if a practical application is not immediately apparent; and (3) of shifting interests and a shortage of key personalities to train a new generation (they switched to marine habitats or other fields). Some of the opportunities for future research are outlined, such as climate change and cryptic species diversity. A significant problem challenging future research seems to be the loss of trained and experienced fish

  11. North America's Midcontinent Rift: when Rift MET Lip

    Science.gov (United States)

    Stein, C. A.; Stein, S. A.; Kley, J.; Keller, G. R., Jr.; Bollmann, T. A.; Wolin, E.; Zhang, H.; Frederiksen, A. W.; Ola, K.; Wysession, M. E.; Wiens, D.; Alequabi, G.; Waite, G. P.; Blavascunas, E.; Engelmann, C. A.; Flesch, L. M.; Rooney, T. O.; Moucha, R.; Brown, E.

    2015-12-01

    Rifts are segmented linear depressions, filled with sedimentary and igneous rocks, that form by extension and often evolve into plate boundaries. Flood basalts, a class of Large Igneous Provinces (LIPs), are broad regions of extensive volcanism due to sublithospheric processes. Typical rifts are not filled with flood basalts, and typical flood basalts are not associated with significant crustal extension and faulting. North America's Midcontinent Rift (MCR) is an unusual combination. Its 3000-km length formed as part of the 1.1 Ga rifting of Amazonia (Precambrian NE South America) from Laurentia (Precambrian North America) and became inactive once seafloor spreading was established, but contains an enormous volume of igneous rocks. MCR volcanics are significantly thicker than other flood basalts, due to deposition in a narrow rift rather than a broad region, giving a rift geometry but a LIP's magma volume. Structural modeling of seismic reflection data shows an initial rift phase where flood basalts filled a fault-controlled extending basin, and a postrift phase where volcanics and sediments were deposited in a thermally subsiding basin without associated faulting. The crust thinned during rifting and rethickened during the postrift phase and later compression, yielding the present thicker crust. The coincidence of a rift and LIP yielded the world's largest deposit of native copper. This combination arose when a new rift associated with continental breakup interacted with a mantle plume or anomalously hot or fertile upper mantle. Integration of diverse data types and models will give insight into questions including how the magma source was related to the rifting, how their interaction operated over a long period of rapid plate motion, why the lithospheric mantle below the MCR differs only slightly from its surroundings, how and why extension, volcanism, and compression varied along the rift arms, and how successful seafloor spreading ended the rift phase. Papers

  12. Factors affecting expanded electricity trade in North America

    Energy Technology Data Exchange (ETDEWEB)

    Hill, L.J.

    1994-01-01

    The authors explore factors that affect electricity trade between enterprises in the US and Canada and the US and Mexico. They look to those underlying policy and institutional factors that affect the relative costs of producing electricity in the three countries. In particular, they consider six factors that appear to have a significant impact on electricity trade in North America: differences in the types of economic regulation of power leading to differences in cost recovery for wholesale and retail power and wheeling charges; changing regulatory attitudes, placing more emphasis on demand-side management and environmental concerns; differences in energy and economic policies; differences in national and subnational environmental policies; changing organization of electric power industries which may foster uncertainty, change historical relationships, and provide other potentially important sources of power for distribution utilities; and differences in the ability of enterprises to gain access to electric power markets because of restrictions placed on transmission access. In Section 2, the authors discuss the regulation of electricity trade in North America and provide an overview of the recent trading experience for electricity between Canada and the US and between Mexico and the US, including the volume of that trade over the past decade and existing transmission capacity between regions of the three countries. In Section 3, they look at the benefits that accrue to trading counties and what those benefits are likely to be for the three countries. The discussion in Section 4 centers on the relevant provisions of the Canada Free Trade Agreement and the proposed North American Free Trade Agreement. In Section 5, they set the stage for the discussion of policy and institutional differences presented in Section 6 by outlining differences in the organization of the electric power sectors of Canada, the US, and Mexico. The study is synthesized in Section 7.

  13. Pollution transport across the Pacific and its impact on North America

    International Nuclear Information System (INIS)

    Full text: We present a study about the transport of pollution across the Pacific and how this long-range transport impacts the atmospheric composition over North America both on a regional and a local scale. Our focus is on spring 2006 when the NASA INTEX-B campaign (Intercontinental Chemical Transport Experiment) took place. The extensive set of aircraft and ground based field observations form the basis for the analysis together with satellite observations from the MOPITT and MODIS instruments and model simulations with the global MOZART-4 model and the regional WRF-Chem model. Model tracers are used to examine the contributions of different regions to pollution levels over the Pacific and to estimate the ozone production from anthropogenic NOx sources in Asia to ozone loadings over the Pacific and North America. We acknowledge the INTEX-B team for providing the measurements. (author)

  14. North Pacific seasonality and the glaciation of North America 2.7 million years ago

    OpenAIRE

    Haug, G. H.; Ganopolski, A.; Sigman, D. M.; Rosell-Mele, A.; G. E. A. Swann; R. Tiedemann; S. L. Jaccard; J. Bollmann; Maslin, M. A.; Leng, M. J.; Eglinton, G.;  ,

    2005-01-01

    In the context of gradual Cenozoic cooling, the timing of the onset of significant Northern Hemisphere glaciation 2.7 million years ago is consistent with Milankovitch’s orbital theory, which posited that ice sheets grow when polar summertime insolation and temperature are low. However, the role of moisture supply in the initiation of large Northern Hemisphere ice sheets has remained unclear. The subarctic Pacific Ocean represents a significant source of water vapour to boreal North America, ...

  15. First Report of the Stable North America Reference Frame (SNARF) Working Group

    Science.gov (United States)

    Blewitt, G.; Bennett, R. A.; Calais, E.; Herring, T. A.; Larson, K. M.; Miller, M. M.; Sella, G.; Snay, R. A.; Tamisiea, M. E.

    2004-05-01

    We report on the first SNARF Workshop funded by NSF EarthScope, held on Jan 27, 2004. The initial SNARF Working Group membership was approved by the UNAVCO Board and is charged with producing a standard reference frame (for studies in North America) and specifying standard procedures to realize such a frame to meet the needs of EarthScope and the UNAVCO community. SNARF is an official IAG working group under the North America Reference Frame (NAREF) sub-commission. There is also a public service element to these activities in that one objective is for SNARF to become part of the definition of the legal reference frame used in the USA and Canada (NAD83), a natural spin-off demanded by society's increasingly sophisticated needs following on the heels of scientific progress. Through the first workshop, the SNARF WG has already begun to address the pressing needs for a North America-fixed reference frame that is stable at the sub-millimeter level, and what is involved in defining a frame with such stability. Velocity solutions from GPS networks covering the North America-Pacific plate boundary (including the Plate Boundary Observatory under construction) are most naturally expressed with respect to the stable interiors of either the North America or Pacific plates. As well as providing a common frame by which to compare results from different analysis groups, such a system makes it easier to interpret the data in terms of where the total budget of relative plate motion is accomodated, and how deep plate boundary dynamics penetrate into the plate interior. Defining a stable frame at the sub-millimeter level requires adequate characterization of kinematics at that level across a sufficiently broad expanse of what may be termed the "plate interior," which deforms due to GIA and other mantle processes, coupled with lithospheric heterogeneity. A dynamically defined velocity datum (as opposed to a purely kinematic choice) is preferable to add interpretive value to site

  16. Statiscal Downscaling of a surface wind field over northeastern North America: annual to centennial variability.

    Science.gov (United States)

    Lucio-Eceiza, Etor E.; Fidel González-Rouco, J.; Navarro, Jorge; García-Bustamante, Elena; Beltrami, Hugo

    2016-04-01

    The region of North Eastern North America is located in a privileged geographical position that allows for interesting relationships between various large-scale circulation modes and the seasonal surface wind. This is a region where the large-scale configurations foster the transit of tropical cyclonic events during the summer season and even more intense extratropical cyclones during winter. In this work we present a statistical downscaling method based on Canonical Correlation Analysis (CCA) that exploits the relationships among the main modes of circulation over the North Atlantic and Pacific Sectors and the behaviour of surface wind. The statistical technique has been implemented with predictor variables (mean sea level pressure and geopotential height at different levels) provided by all the reanalysis products available to date. The regional scale data consist of a set of 526 sites distributed over North Eastern North America that span over a period of about 60 years (1953-2010). These data have been previously subjected to an exhaustive quality control process, height standardization and wind direction homogenization. Several decades of observations allow for the study of intra to multidecadal variability. Also, the sensitivity of the downscaling methodology to the selection of a systematic sampling of model parameter values has been explored. The statistical relationship obtained by this method also allows for the reconstruction of the regional wind behaviour back to the mid 19th century through various 20th century reanalysis and instrumental sea level pressure datasets.

  17. The physical demands of electrical utilities work in North America.

    Science.gov (United States)

    Meade, Robert D; Lauzon, Martin; Poirier, Martin P; Flouris, Andreas D; Kenny, Glen P

    2016-01-01

    We assessed the physical demands associated with electrical utilities work in North America and how they influence the level of thermal and cardiovascular strain experienced. Three common job categories were monitored as they are normally performed in thirty-two electrical utility workers: (i) Ground Work (n = 11), (ii) Bucket Work (n = 9), and (iii) Manual Pole Work (n = 12). Video analysis was performed to determine the proportion of the work monitoring period (duration: 187 ± 104 min) spent at different levels of physical effort (i.e., rest as well as light, moderate and heavy effort). Core and skin temperatures as well as heart rate were measured continuously. On average, workers spent 35.9 ± 15.9, 36.8 ± 17.8, 24.7 ± 12.8, and 2.6 ± 3.3% of the work period at rest and performing work classified as light, moderate, and heavy physical effort, respectively. Moreover, a greater proportion of the work period was spent performing heavy work in Ground Work (1.6 ± 1.4%) relative to Bucket Work (0.0 ± 0.0%; Pwork job (both P≤0.03). Furthermore, the proportion of time spent during work classified as heavy physical effort was positively correlated to the mean (r = 0.51, Pwork period as well as the mean heart rate response (presented as a percentage of heart rate reserve; r = 0.40, P = 0.03). Finally, mean and peak core temperatures and mean heart rate responses increased from the first to the second half of the work shift; however, no differences in the proportion of the work spent at the different intensity classifications were observed. We show that Manual Pole Work is associated with greater levels of physical effort compared to Ground or Bucket Work. Moreover, we suggest that the proportion of time spent performing work classified as heavy physical exertion is related to the level of thermal and cardiovascular strain experienced and that workers may not be employing self-pacing as a strategy to manage their level of physiological strain.

  18. Developments in Ground-Motion Modeling in Eastern North America

    Science.gov (United States)

    Atkinson, G. M.; Boore, D. M.

    2012-12-01

    Recent well-recorded earthquakes in Eastern North America (ENA) have led us to re-evaluate concepts that have been "standard fare" in the development of ground-motion prediction equations (GMPEs) for ENA for decades, including all published GMPEs that are used in current practice (e.g. Atkinson and Boore, 2011, 2006, 1995; Pezeshk et al., 2011; Campbell, 2003; Toro et al., 1997, etc.). Assumptions common to all ENA GMPEs that may not be true include the following. (1) Typical ENA stress drops, in the context of a Brune model representation of the source spectrum, are in the range of 150-300 bars, with the exception of occasional high-stress events like the 1988 Saguenay earthquake. (2) Attenuation of ground motions can be modeled with a frequency-independent geometric spreading function, either bilinear or trilinear in shape (e.g. Street and Turcotte, 1975; Herrmann and Kijko, 1983; Atkinson and Mereu, 1992; Atkinson, 2004; Boatwright and Seekins, 2011), and an associated frequency-dependent anelastic attenuation term related to the regional Quality factor. The use of a bilinear or trilinear form models the transition from geometric spreading of body waves at close distances to slower surface-wave-type spreading at regional distances. We use ground-motion recordings from recent ENA events to re-examine these basic tenets of GMPE development, in light of constraints on the problem provided at low frequencies by seismic moment, and at high frequencies by stresses inferred from Empirical Greens Function (EGF) analysis. We find strong evidence, in both ground-motion data and from the constraints, that geometric attenuation may be frequency dependent. Moreover, EGF stress drops may be very high (>500 bars) - but they do not lead to particularly large high-frequency ground motions, at least at distances for which we have observations. More complex models of ENA source and attenuation processes appear to be required in order to reconcile our growing ground-motion database

  19. Cross-continental patterns in the timing of southward Peregrine Falcon migration in North America

    NARCIS (Netherlands)

    Worcester, R.; Ydenberg, R.C.

    2008-01-01

    We analyzed the timing of southward migration of Peregrine Falcons (Falco peregrinus) across North America, based on passage data compiled by the Hawk Migration Association of North America, supplemented with two other similar datasets collected by individual observers at sites in western Canada. Th

  20. 76 FR 35249 - Allianz Life Insurance Company of North America, et al; Notice of Application

    Science.gov (United States)

    2011-06-16

    ... COMMISSION Allianz Life Insurance Company of North America, et al; Notice of Application June 10, 2011... Section 17(b) of the Act from Section 17(a) of the Act. Applicants: Allianz Life Insurance Company of North America (``Allianz Life'') and Allianz Life Insurance Company of New York (``Allianz...

  1. 78 FR 76408 - BMW of North America, LLC, Grant of Petition for Decision of Inconsequential Noncompliance

    Science.gov (United States)

    2013-12-17

    ... Register (77 FR 63415). One comment was received from Anne K. Mayer which supported granting BMW's petition... National Highway Traffic Safety Administration BMW of North America, LLC, Grant of Petition for Decision of... Transportation (DOT). ACTION: Grant of Petition. SUMMARY: BMW North America, LLC,\\1\\ a subsidiary of BMW...

  2. An atypical biotype I Actinobacillus pleuropneumoniae serotype 13 is present in North America

    DEFF Research Database (Denmark)

    Perry, Malcolm B.; Angen, Øystein; MacLean, Leann L.;

    2012-01-01

    Atypical Actinobacillus pleuropneumoniae serotype 13 strains present in North America are described here for the first time. Different from serotype 13 strains described in Europe, North America strains are biotype I and antigenically related to both, serotypes 13 and 10. Chemical and structural...

  3. Recent trends in gas contracting in North America

    International Nuclear Information System (INIS)

    An overview of recent business trends impacting upon natural gas contracting in North America is provided. Among the trends examined are supply and demand, natural gas prices, access to the U.S. market, gas sales contracts, electronic gas sales, retail level marketing, the growing popularity of 'one-stop shopping', and standardization of contracts. Overall, supplies appear to be adequate for now, demand is growing, prices are volatile, short-term contracts are more popular than long-term ones, electronic commerce combined with one-stop shopping marketing at the retail level is growing, and standardization of spot and short-term gas sales contracts is slowly being accepted by industry as a means to to improve the efficiency of the market. 12 refs

  4. Optimizing Large Scale Carbon Fluxes for North America

    Science.gov (United States)

    Schuh, A. E.; Denning, A. S.; Corbin, K. D.; Ulliasz, M.; Parazoo, N. C.

    2008-12-01

    We combine the SiB3 biosphere model with the RAMS mesoscale meteorology model and associated Lagrangian particle dispersion model (LPDM) and use CO2 observations from a 8-tower network in 2004 to correct a priori ecosystem respiration (ER) and gross primary productivity (GPP) fluxes for a domain consisting of most of North America. Results are presented as weekly corrections to ER and GPP for 2004. A sink is recovered from the inversion but is smaller than expected due to the limited constraint imposed by the sampling footprint of the 8-tower observing network. The sensitivities of the inversion to independently derived boundary conditions, different fossil fuel sources, and various parameters in the inversion are analyzed and discussed.

  5. The paradigm of grizzly bear restoration in North America

    Science.gov (United States)

    Schwartz, C. C.; Maehr, David S.; Noss, Reed F.; Larkin, J.L.

    2002-01-01

    Grizzly bear restoration and recovery is a controversial, highly politicized process. By 1959, when the Craigheads began their pioneering work on Yellowstone grizzly bears, the species had been reduced to a remnant of its historic range. Prior to the colonization of North America by Europeans, the grizzly lived in relatively pristine habitats with aboriginal Native Americans. As civilization expanded, humans changed the face of the landscape, converting grizzly bear habitat to farms and ranches. People killed grizzlies to protect livestock and eliminate a perceived threat to human safety. In concert, habitat loss and direct human-caused mortality had effectively eliminated the grizzly from 95 percent of its historic range in the conterminous United States by the 1920s (Servheen 1989). Grizzly bear numbers had been reduced nearly 98 percent by 1975 when the species was listed as threatened under the Endangered Species Act (ESA) (USFWS 1993).

  6. Reducing inequities in colorectal cancer screening in North America

    Directory of Open Access Journals (Sweden)

    Kathleen M Decker

    2014-01-01

    Full Text Available Colorectal cancer (CRC is an important cause of mortality and morbidity in North America. Screening using a fecal occult blood test, flexible sigmoidoscopy, or colonoscopy reduces CRC mortality through the detection and treatment of precancerous polyps and early stage CRC. Although CRC screening participation has increased in recent years, large inequities still exist. Minorities, new immigrants, and those with lower levels of education or income are much less likely to be screened. This review provides an overview of the commonly used tests for CRC screening, disparities in CRC screening, and promising methods at the individual, provider, and system levels to reduce these disparities. Overall, to achieve high CRC participation rates and reduce the burden of CRC in the population, a multi-faceted approach that uses strategies at all levels to reduce CRC screening disparities is urgently required.

  7. Palm harvest impacts in north-western South America

    DEFF Research Database (Denmark)

    Balslev, Henrik

    2011-01-01

    Tropical forests harbor thousands of useful plants that are harvested and used in subsistence economies or traded in local, regional or international markets. The effect on the ecosystem is little known, and the forests resilience is badly understood. Palms are the most useful group of plants...... in tropical American forests. This paper introduces a cross-disciplinary study of the effects of harvesting palm products from the tropical forests in north-western South America. The size of the resource is estimated through palm community studies in the different forest formations that determines the number...... for subsistence purposes Quantitative ethno-botanical research in different forest types have identified thousands of different ways of using palms for food, construction, tool-making, etc. Although most palms are used by the person harvesting them, many are sold on local markets as fruits, fiber, tools...

  8. Missourian (early Late Pennsylvanian) climate in Midcontinent North America

    Energy Technology Data Exchange (ETDEWEB)

    Schutter, S.R.; Heckel, P.H.

    1985-06-01

    The abrupt decrease in mineable coals from Desmoinesian to Missourian rocks in Midcontinent North America has been related by several lines of evidence to the probability that Missourian climate became at least seasonally drier than Desmoinesian climate. This represents a transition from the equatorial Desmoinesian rainforest climate to the arid Permian climate, as North America moved northward from the equator. This change is reflected in the progression of evaporites from western Colorado in the Desmoinesian to Kansas in the Permian. Direct climatic evidence from soils in two Missourian shales deposited at low stands of sea-level includes caliche horizons, incompletely leached mixed-layer clays. Less direct climatic evidence includes the greater proportion of marine limestone deposited at intermediate sea-level stands in the Missourian than in the Desmoinesian part of the sequence, in conjunction with the greater abundance and thickness of oolite and shore-line facies in Missourian limestones than in Desmoinesian counterparts. This probably reflects increasing dryness of the climate, which would have led to decreased detrital influx and increased salinity as rainfall and runoff diminished. Indirect climatic evidence in offshore black phosphatic shales deposited at highest sea-level stands involves possible seasonality in organic and phosphatic laminations, related to periodicity of upwelling in the tropical trade-wide belt under the strong monsoonal influence of Pangaea. Mid-continent Missourian climates probably ranged from tropical monsoon to tropical savanna or hot steppe, all having wet-dry seasonality. The coincident extinctions of conodont, brachiopod, and other marine genera as well as the loss of swamp lycopods at the end of the Desmoinesian suggest the possibility that a greater than usual drop in sea level affected both realms at this time, while the climate was becoming drier. 91 references.

  9. BTU convergence spawning gas market opportunities in North America

    International Nuclear Information System (INIS)

    The so-called BTU convergence of US electric power and natural gas sectors is spawning a boom in market opportunities in the US Northeast that ensures the region will be North America's fastest growing gas market. That's the view of Catherine Good Abbott, CEO of Columbia Gas Transmission Corp., who told a Ziff Energy conference in Calgary that US Northeast gas demand is expected to increase to almost 10 bcfd in 2000 and more than 12 bcfd in 2010 from about 8 bcfd in 1995 and only 3 bcfd in 1985. The fastest growth will be in the US Northeast's electrical sector, where demand for gas is expected to double to 4 bcfd in 2010 from about 2 bcfd in 1995. In other presentations at the Ziff Energy conference, speakers voiced concerns about the complexity and speed of the BTU convergence phenomenon and offered assurances about the adequacy of gas supplies in North American to meet demand growth propelled by the BTU convergence boom. The paper discusses the gas demand being driven by power utilities, the BTU convergence outlook, electric power demand, Canadian production and supply, and the US overview

  10. Nested-grid simulation of mercury over North America

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2012-01-01

    Full Text Available We have developed a new high-resolution (1/2° latitude by 2/3° longitude nested-grid mercury (Hg simulation over North America employing the GEOS-Chem global chemical transport model. Emissions, chemistry, deposition, and meteorology are self-consistent between the global and nested domains. Compared to the global model (4° latitude by 5° longitude, the nested model shows improved skill at capturing the high spatial and temporal variability of Hg wet deposition over North America observed by the Mercury Deposition Network (MDN in 2008–2009. The nested simulation resolves features such as land/ocean contrast and higher deposition due to orographic precipitation, and predicts more efficient convective rain scavenging of Hg over the southeast United States. However, the nested model overestimates Hg wet deposition over the Ohio River Valley region (ORV by 27%. We modify anthropogenic emission speciation profiles in the US EPA National Emission Inventory (NEI to account for the rapid in-plume reduction of reactive to elemental Hg (IPR simulation. This leads to a decrease in the model bias to +3% over the ORV region. Over the contiguous US, the correlation coefficient (r between MDN observations and our IPR simulation increases from 0.63 to 0.78. The IPR nested simulation generally reproduces the seasonal cycle in surface concentrations of speciated Hg from the Atmospheric Mercury Network (AMNet and Canadian Atmospheric Mercury Network (CAMNet. In the IPR simulation, annual mean reactive gaseous and particulate-bound Hg are within 80% and 10% of observations, respectively. In contrast, the simulation with unmodified anthropogenic Hg speciation profiles overestimates these observations by factors of 2 to 4. The nested model shows improved skill at capturing the horizontal variability of Hg observed over California during the ARCTAS aircraft campaign. We find that North American anthropogenic emissions account for 10–22% of Hg wet

  11. Phylogenetic analysis of spring virema of carp virus reveals distinct subgroups with common origins for recent isolates in North America and the UK.

    Science.gov (United States)

    Miller, O; Fuller, F J; Gebreyes, W A; Lewbart, G A; Shchelkunov, I S; Shivappa, R B; Joiner, C; Woolford, G; Stone, D M; Dixon, P F; Raley, M E; Levine, J F

    2007-07-16

    Genetic relationships between 35 spring viremia of carp virus (SVCV) genogroup Ia isolates were determined based on the nucleotide sequences of the phosphoprotein (P) gene and glycoprotein (G) genes. Phylogenetic analysis based on P gene sequences revealed 2 distinct subgroups within SVCV genogroup Ia, designated SVCV Iai and Iaii, and suggests at least 2 independent introductions of the virus into the USA in 2002. Combined P- and G-sequence data support the emergence of SVCV in Illinois, USA, and in Lake Ontario, Canada, from the initial outbreak in Wisconsin, USA, and demonstrate a close genetic link to viruses isolated during routine import checks on fish brought into the UK from Asia. The data also showed a genetic link between SVCV isolations made in Missouri and Washington, USA, in 2004 and the earlier isolation made in North Carolina, USA, in 2002. However, based on the close relationship to a 2004 UK isolate, the data suggest than the Washington isolate represents a third introduction into the US from a common source, rather than a reemergence from the 2002 isolate. There was strong phylogenetic support for an Asian origin for 9 of 16 UK viruses isolated either from imported fish, or shown to have been in direct contact with fish imported from Asia. In one case, there was 100% nucleotide identity in the G-gene with a virus isolated in China.

  12. 75 FR 20390 - Robert Bosch LLC, Including On-Site Leased Workers From Bosch Management Services North America...

    Science.gov (United States)

    2010-04-19

    ... Management Services North America, South Haven Community Hospital, Huffmaster Inc., and Williamson Employment... Management Services North America, South Haven Community Hospital, Huffmaster Inc., and Williamson Employment..., including on-site leased workers of Bosch Management Services North America, South Haven Community...

  13. Uranium production capability: North America, Australia, Asia and Africa

    International Nuclear Information System (INIS)

    With the apparent need for additional primary uranium supply, the paper discusses necessary preconditions for mine construction and then reviews the supply potential in North America, Australia, Africa and Asia. Canadian uranium supply will increase from 12 000 t U to over 16 000 t U by 2011 with the commencement of production at the Cigar Lake mine and the eventual mining of the Midwest Lake deposit. Canadian production levels will then begin a slow and steady decline from 2014 onwards as existing economic deposits become exhausted. Production in the United States of America will continue to be dominated by in situ leech mines but certain conventional mines will provide some additional production. Total US production may reach 4000 t U by 2010. Future Australian production levels are clouded in uncertainty. Restrictive Government policies are once again having an impact on uranium prices. A potential tripling of production at Olympic Dam, however, will have a dramatic impact on uranium supplies if a decision to expand production is indeed made. Depending upon market forces, Government and corporate decisions, uranium production in Australia could vary from as little as 4500 t U to as much as 22 000 t U by 2020. After 30 years of production, Phase 1 mining at the Roessing mine in Namibia is nearly complete and the mine is now faced with a series of difficult decisions in order to remain in operation beyond 2009. Steady output from existing mines in Niger is expected for at least a further ten years, and additional mining opportunities have been identified. Other potential African production sources are also discussed. Mongolia has the potential to become a new modest sized producer, depending upon the outcome of further studies. Production levels in India and China are expected to increase modestly in order to help satisfy domestic needs. (author)

  14. Predicting Pleistocene climate from vegetation in North America

    Science.gov (United States)

    Loehle, C.

    2007-02-01

    Climates at the Last Glacial Maximum have been inferred from fossil pollen assemblages, but these inferred climates are colder for eastern North America than those produced by climate simulations. It has been suggested that low CO2 levels could account for this discrepancy. In this study biogeographic evidence is used to test the CO2 effect model. The recolonization of glaciated zones in eastern North America following the last ice age produced distinct biogeographic patterns. It has been assumed that a wide zone south of the ice was tundra or boreal parkland (Boreal-Parkland Zone or BPZ), which would have been recolonized from southern refugia as the ice melted, but the patterns in this zone differ from those in the glaciated zone, which creates a major biogeographic anomaly. In the glacial zone, there are few endemics but in the BPZ there are many across multiple taxa. In the glacial zone, there are the expected gradients of genetic diversity with distance from the ice-free zone, but no evidence of this is found in the BPZ. Many races and related species exist in the BPZ which would have merged or hybridized if confined to the same refugia. Evidence for distinct southern refugia for most temperate species is lacking. Extinctions of temperate flora were rare. The interpretation of spruce as a boreal climate indicator may be mistaken over much of the region if the spruce was actually an extinct temperate species. All of these anomalies call into question the concept that climates in the zone south of the ice were extremely cold or that temperate species had to migrate far to the south. An alternate hypothesis is that low CO2 levels gave an advantage to pine and spruce, which are the dominant trees in the BPZ, and to herbaceous species over trees, which also fits the observed pattern. Thus climate reconstruction from pollen data is probably biased and needs to incorporate CO2 effects. Most temperate species could have survived across their current ranges at lower

  15. Status of woodland caribou in western north America

    Directory of Open Access Journals (Sweden)

    E. Janet Edmonds

    1991-10-01

    Full Text Available A review of current population size and trends of woodland caribou (Rangifer tarandus caribou in seven jurisdictions in western North America shows a wide range of situations. A total maximum population estimate of woodland caribou west of the Ontario/Manitoba border is 61 090. Of 44 herds or populations described in this review: 14 are stable; two are stable to slightly decreasing; four are decreasing; four are increasing; and 22 are of unknown status. Caribou are classified as a threatened species in Alberta and as an endangered species in Washington/Idaho. The decline of caribou in North America following settlement (Bergerud, 1974 has continued along the southern edge of woodland caribou distribution. Direct loss of habitat to logging, mines and dams continued throughout the I960s, 1970s and 1980s. The secondary effects of these habitat changes, (i.e. increased roads leading to increased hunting and poaching, and increased early succession habitat leading to increased alternate prey/predator densities has led in some cases to the total loss or decreased size of local herds. Three ecotypes of woodland caribou are described and their relative distribution delineated. These ecotypes live under different environmental conditions and require different inventory and management approaches. Woodland caribou herds in northern B.C., Yukon and N.W.T. generally are of good numbers and viable (stable or increasing, and management primarily is directed at regulating human harvest and natural predation to prevent, herd declines. Land use activities such as logging or energy development are not extensive. Managers in southern caribou ranges stress the need for a better understanding of caribou population stability within mixed prey/predator regimes; how habitat changes (eg. through logging affect these regimes; and how to develop effective land use guidelines for resource extraction that can sustian caribou populations and maintain resource industries

  16. Magnitude and Carbon Consequences of Forest Management in North America

    Science.gov (United States)

    Masek, J.; Kurz, W.; de Jong, B. H.

    2009-12-01

    The carbon balance of forests depends on the type, frequency and severity of recent disturbances (carbon source) and the rate of recovery from past disturbance (carbon sink). Harvest and land cover conversion represent significant forest disturbance agents over much of North America. For example, pine forests in the southeastern US are typically harvested at ~20 year intervals, and may occupy about half the regional landscape, resulting in regional landscape turnover rates of 2-3% per year. Inventory data are the primary source for quantifying information on harvest and conversion in the U.S., Mexico, and Canada. Recent inventory data from these countries indicate timber production of 424 million cu m, 163 million cu m, and 7 million cu m, respectively, with significant year-to-year variability associated with wood products demand and timber price. Areas affected by harvest activity vary as well, with 3.97 Mha (million hectares) and 1.04 Mha affected by harvest in the US and Canada, respectively. Forest cover conversion (deforestation) is thought to be relatively minor in the US and Canada, but recent estimates suggest that forest and woodland cover in Mexico declined by 300-500 Kha/yr during the 1990’s. Recently, satellite remote sensing data products on forest change have been generated that complement the traditional inventory approach. These products are particularly useful for “wall-to-wall” estimates of forest conversion and tracking small disturbances. The type and severity of disturbance cannot be easily determined using satellite observations, however, and therefore some care must be taken to reconcile these products with ground-based data. In this talk we review available resources for characterizing “carbon relevant” information on the magnitude (area, type of activity) of forest management in North America, and attempt a first-order comparison between remote sensing and inventory estimates. We also discuss strategies that might be employed to

  17. Shaded Relief with Height as Color, North America

    Science.gov (United States)

    2003-01-01

    This image of North America was generated with data from the Shuttle Radar Topography Mission (SRTM). For this broad view the resolution of the data was first reduced to 30 arcseconds (about 928 meters north-south and 736 meters east-west in central North America), matching the best previously existing global digital topographic data set called GTOPO30. The data were then resampled to a Mercator projection with approximately square pixels (about one kilometer, or 0.6 miles, on each side). Even at this decreased resolution the variety of landforms comprising the North American continent is readily apparent.Active tectonics (structural deformation of the Earth's crust) along and near the Pacific -- North American plate boundary creates the great topographic relief seen along the Pacific coast. Earth's crustal plates converge in southern Mexico and in the northwest United States, melting the crust and producing volcanic cones. Along the California coast, the plates are sliding laterally past each other, producing a pattern of slices within the San Andreas fault system. And, where the plates are diverging, the crust appears torn apart as one huge tear along the Gulf of California (northwest Mexico), and as the several fractures comprising the Basin and Range province (in and around Nevada).Across the Great Plains, erosional patterns dominate, with streams channels surrounding and penetrating the remnants of older smooth slopes east of the Rocky Mountains. This same erosion process is exposing the bedrock structural patterns of the Black Hills in South Dakota and the Ozark Mountains in Arkansas. Lateral erosion and sediment deposition by the Mississippi River has produced the flatlands of the lower Mississippi Valley and the Mississippi Delta.To the north, evidence of the glaciers of the last ice age is widely found, particularly east of the Canadian Rocky Mountains and around the Great Lakes. From northeastern British Columbia, across Alberta, Saskatchewan, and

  18. Molecular characterization of H1N1 influenza A viruses from human cases in North America

    Institute of Scientific and Technical Information of China (English)

    WU Bin; WANG ChengMin; DONG GuoYing; LUO Jing; ZHAO BaoHua; HE HongXuan

    2009-01-01

    Subtypes of H1N1 influenza virus can be found in humans in North America,while they are also associated with the infection of swine.Characterization of the genotypes of viral strains in human populations is important to understand the source and distribution of viral strains.Genomic and protein sequences of 10 isolates of the 2009 outbreak of influenza A (H1N1) virus in North America were obtained from GenBank database.To characterize the genotypes of these viruses,phylogenetic trees of genes PB2,PB1,PA,HA,NP,NA,NS and M were constructed by Phylip3.67 program and N-Linked glycosylation sites of HA,NA,PB2,NS1 and M2 proteins were analyzed online by NetNGIyc1.0 program.Phylogenetic analysis indicated that these isolates are virtually identical but may be recombinant viruses because their genomic fragments come from different viruses.The isolates also contain a characteristic lowly pathogenic amino acid motif at their HA cleavage sites (IPSIQSR↓GL),and an E residue at position 627 of the PB2 protein which shows its high affinity to humans.The homologous model of M proteins showed that the viruses had obtained the ability of anti-amantadine due to the mutation at the drug-sensitive site,while sequence analysis of NA proteins indicated that the viruses are still susceptible to the neuraminidase inhibitor drug (i.e.oseltamivir and zanamivir) because no mutations have been observed.Our results strongly suggested that the viruses responsible for the 2009 outbreaks of influenza A (H1N1) virus have the ability to cross species barriers to infect human and mammalian animals based on molecular analysis.These findings may further facilitate the therapy and prevention of possible transmission from North America to other countries.

  19. Climate directly influences Eocene mammal faunal dynamics in North America.

    Science.gov (United States)

    Woodburne, Michael O; Gunnell, Gregg F; Stucky, Richard K

    2009-08-11

    The modern effect of climate on plants and animals is well documented. Some have cautioned against assigning climate a direct role in Cenozoic land mammal faunal changes. We illustrate 3 episodes of significant mammalian reorganization in the Eocene of North America that are considered direct responses to dramatic climatic events. The first episode occurred during the Paleocene-Eocene Thermal Maximum (PETM), beginning the Eocene (55.8 Ma), and earliest Wasatchian North American Land Mammal Age (NALMA). The PETM documents a short (<170 k.y.) global temperature increase of approximately 5 degrees C and a substantial increase in first appearances of mammals traced to climate-induced immigration. A 4-m.y. period of climatic and evolutionary stasis then ensued. The second climate episode, the late early Eocene Climatic Optimum (EECO, 53-50 Ma), is marked by a temperature increase to the highest prolonged Cenozoic ocean temperature and a similarly distinctive continental interior mean annual temperature (MAT) of 23 degrees C. This MAT increase [and of mean annual precipitation (MAP) to 150 cm/y) promoted a major increase in floral diversity and habitat complexity under temporally unique, moist, paratropical conditions. Subsequent climatic deterioration in a third interval, from 50 to 47 Ma, resulted in major faunal diversity loss at both continental and local scales. In this Bridgerian Crash, relative abundance shifted from very diverse, evenly represented, communities to those dominated by the condylarth Hyopsodus. Rather than being "optimum," the EECO began the greatest episode of faunal turnover of the first 15 m.y. of the Cenozoic. PMID:19666605

  20. School and community relations in North America: Creative tensions

    Science.gov (United States)

    Loughran, E.; Reed, H. B.

    1980-09-01

    School and community relations in North America reflect creative tensions between the conserving forces of schooling and the changing forces of community. During crisis periods community development needs may modify the school's focus on individual learner growth, but generally schools use the community to extend and enrich the traditional modes. School and community interactions are chiefly characterized by such settings as community schools, community education, adult education, home and school (PTA) associations, work-study programs, curriculum-community resource programs. Recent social forces are creating heightened tensions: cultural pluralism, reduced resources, Third World influences, international conflicts, personal alienation, population concerns, energy problems, community power issues. These forces are gradually shifting school and community concepts towards ones of education and community. Education goes well beyond schooling, including all agencies having an organized influence on community development: libraries, voluntary groups, unions, business, human service agencies, government units, as well as schools. This shift requires research to develop nonformal concepts and practices, along with formal pedagogy, to increase the positive impacts of educational networks on community, as well as individual, development. These new directions have not yet significantly modified the traditional meaning of school and community relations.

  1. In the spotlight: New hydro development in North America

    International Nuclear Information System (INIS)

    1992 was a year of progress for many segments of the hydropower industry as developers worked to bring new projects on line. This industry overview features several of these projects and offers a preview of 1993 activity. The only operating privately owned hydroelectric project in Texas. The largest hydro plant in the province of Manitoba. The world's largest submersible hydroturbine-generator. These projects and others-completed and placed in service in 1992-can claim a special place in the history books. For each of the 31 hydro projects in North America that began operating in 1992, there's a unique story to tell. Each called upon the time, talent, commitment, ingenuity, and perseverance of those involved in their development. In aggregate, these projects contribute nearly 3,800 MW of clean, renewable electrical capacity that can be used efficiently and cost-effectively to help meet the power demands of customers in the US and Canada. Utilities, state agencies, municipalities, and independent power developers played roles in developing new hydro in 1992. We offer a sampling of their work to illustrate progress made in the past year

  2. Energy balances for Europe and North America 1970-2000

    International Nuclear Information System (INIS)

    This publication is based on the ECE Energy Data Bank collected by the Senior Advisers to ECE Governments on Energy, supplemented by other official data available to the secretariat. The Energy Data Base contains energy balances from 1960 to 1985 for the market economy countries of western Europe and North America and from 1965 to 1985 for the centrally planned economy countries of eastern Europe. During the first session of the Senior Advisers to ECE Governments on Energy held in 1979, countries decided to circulate a questionnaire on Selected Energy Issues covering the years 1973, 1978, 1980, 1985, 1990 and 2000 (ECE/ENERGY/2, para. 29). While the methodology for establishing the balances has been mutually agreed, the assumptions underlying each country's forecast are not necessarily comparable. At their fifth session held from 23 to 27 September 1985, the Senior Advisers to ECE Governments on Energy agreed to issue a second questionnaire to collect revised projections for the years 1990 and 2000 (ECE/ENERGY/11, para. 50(b)). Information received served as benchmarks to construct a time series from 1970 to 1985. Commodities listed include solid fossil fuels, petroleum fuels, gaseous fuels both natural and derived, nuclear energy, hydro- and geothermal energy, electricity, steam and hot water, energy derived from non-conventional energy sources (solar, wind, wave, tidal, etc.)

  3. Ecosystem biophysical memory in the southwestern North America climate system

    International Nuclear Information System (INIS)

    To elucidate the potential role of vegetation to act as a memory source in the southwestern North America climate system, we explore correlation structures of remotely sensed vegetation dynamics with precipitation, temperature and teleconnection indices over 1982–2006 for six ecoregions. We found that lagged correlations between vegetation dynamics and climate variables are modulated by the dominance of monsoonal or Mediterranean regimes and ecosystem-specific physiological processes. Subtropical and tropical ecosystems exhibit a one month lag positive correlation with precipitation, a zero- to one-month lag negative correlation with temperature, and modest negative effects of sea surface temperature (SST). Mountain forests have a zero month lag negative correlation with precipitation, a zero–one month lag negative correlation with temperature, and no significant correlation with SSTs. Deserts show a strong one–four month lag positive correlation with precipitation, a low zero–two month lag negative correlation with temperature, and a high four–eight month lag positive correlation with SSTs. The ecoregion-specific biophysical memories identified offer an opportunity to improve the predictability of land–atmosphere interactions and vegetation feedbacks onto climate. (letter)

  4. The first vineyard concert hall in North America

    Science.gov (United States)

    Jaffe, Christopher; Rivera, Carlos

    2002-11-01

    The first vineyard or surround concert hall designed and built in the Western Hemisphere is the Sala Nezahualcoyotl in Mexico City. The Hall was completed in 1976 and is part of the Cultural Center at the Universidad Nacional Autonoma de Mexico. The hall was named after a Toltec poet, architect, and musician who lived in the 15th century and was the Renaissance man of his day. In order to provide the familiar traditional sound of the rectangular (shoebox) European Hall, the acoustic designers set the criteria for reverberation times through the frequency spectrum and the Initial Time Delay Gap at every seat in the house to match the measurements taken at the Grosser Musik vereinssaal in Vienna and Boston Symphony Hall. In this paper we discuss the techniques used to create the traditional sound in a vineyard hall and the reaction of musicians and audiences to the completed facility. The Sala was the model for Suntory Hall in Japan which in turn spawned a number of vineyard halls in Japan. Most recently, the vineyard style seems to be appealing to more and more symphonic organizations in Europe and North America.

  5. Surface electric fields for North America during historical geomagnetic storms

    Science.gov (United States)

    Wei, Lisa H.; Homeier, Nicole; Gannon, Jennifer L.

    2013-08-01

    To better understand the impact of geomagnetic disturbances on the electric grid, we recreate surface electric fields from two historical geomagnetic storms—the 1989 "Quebec" storm and the 2003 "Halloween" storms. Using the Spherical Elementary Current Systems method, we interpolate sparsely distributed magnetometer data across North America. We find good agreement between the measured and interpolated data, with larger RMS deviations at higher latitudes corresponding to larger magnetic field variations. The interpolated magnetic field data are combined with surface impedances for 25 unique physiographic regions from the United States Geological Survey and literature to estimate the horizontal, orthogonal surface electric fields in 1 min time steps. The induced horizontal electric field strongly depends on the local surface impedance, resulting in surprisingly strong electric field amplitudes along the Atlantic and Gulf Coast. The relative peak electric field amplitude of each physiographic region, normalized to the value in the Interior Plains region, varies by a factor of 2 for different input magnetic field time series. The order of peak electric field amplitudes (largest to smallest), however, does not depend much on the input. These results suggest that regions at lower magnetic latitudes with high ground resistivities are also at risk from the effect of geomagnetically induced currents. The historical electric field time series are useful for estimating the flow of the induced currents through long transmission lines to study power flow and grid stability during geomagnetic disturbances.

  6. Surface electric fields for North America during historical geomagnetic storms

    Science.gov (United States)

    Wei, Lisa H.; Homeier, Nichole; Gannon, Jennifer L.

    2013-01-01

    To better understand the impact of geomagnetic disturbances on the electric grid, we recreate surface electric fields from two historical geomagnetic storms—the 1989 “Quebec” storm and the 2003 “Halloween” storms. Using the Spherical Elementary Current Systems method, we interpolate sparsely distributed magnetometer data across North America. We find good agreement between the measured and interpolated data, with larger RMS deviations at higher latitudes corresponding to larger magnetic field variations. The interpolated magnetic field data are combined with surface impedances for 25 unique physiographic regions from the United States Geological Survey and literature to estimate the horizontal, orthogonal surface electric fields in 1 min time steps. The induced horizontal electric field strongly depends on the local surface impedance, resulting in surprisingly strong electric field amplitudes along the Atlantic and Gulf Coast. The relative peak electric field amplitude of each physiographic region, normalized to the value in the Interior Plains region, varies by a factor of 2 for different input magnetic field time series. The order of peak electric field amplitudes (largest to smallest), however, does not depend much on the input. These results suggest that regions at lower magnetic latitudes with high ground resistivities are also at risk from the effect of geomagnetically induced currents. The historical electric field time series are useful for estimating the flow of the induced currents through long transmission lines to study power flow and grid stability during geomagnetic disturbances.

  7. Boettger stoneware from North America and Europe; are they authentic

    International Nuclear Information System (INIS)

    In the early 18th century, Johann Friedrich Boettger, an alchemist recently arrived in Dresden, was assigned to ceramic experimentation under the orders of Augustus the Strong, Elector of Saxony and King of Poland. The Elector and his advisors hoped to discover the secret of making hard paste porcelain like the wares imported into Europe from China and Japan. In 1706-1707, Boettger produced his first ceramic body, a red stoneware similar to the wares produced in Yixing, China. The first objects were made following the forms of chinese prototypes or European metalwork of the period. Recently, the authenticity of a number of 'Boettger' objects in various museums and private collections in North America and Europe has been questioned. To aide in resolving these questions several non-destructive analytical techniques have been employed, the most important being PIXE. This report is on an initial study of 25 objects with 16 elements from Al to Zr and Pb being analysed. The results strongly suggest three different groupings, one of objects from the Meissen factory during the 20th century, one from the work of Boettger himself early in the 18th century and one from an as yet unknown time period and site. The first two groups were previously identified by one of the authors (C.N.)

  8. Can coyotes affect deer populations in Southeastern North America?

    Energy Technology Data Exchange (ETDEWEB)

    Kilgo, J., C.; Ray, H., Scott; Ruth, Charles; Miller, Karl, V.

    2010-07-01

    ABSTRACT The coyote (Canis latrans) is a recent addition to the fauna of eastern North America, and in many areas coyote populations have been established for only a decade or two. Although coyotes are known predators of white-tailed deer (Odocoileus virginianus) in their historic range, effects this new predator may have on eastern deer populations have received little attention. We speculated that in the southeastern United States, coyotes may be affecting deer recruitment, and we present 5 lines of evidence that suggest this possibility. First, the statewide deer population in South Carolina has declined coincident with the establishment and increase in the coyote population. Second, data sets from the Savannah River Site (SRS) in South Carolina indicate a new mortality source affecting the deer population concurrent with the increase in coyotes. Third, an index of deer recruitment at SRS declined during the period of increase in coyotes. Fourth, food habits data from SRS indicate that fawns are an important food item for coyotes during summer. Finally, recent research from Alabama documented significant coyote predation on fawns there. Although this evidence does not establish cause and effect between coyotes and observed declines in deer recruitment, we argue that additional research should proactively address this topic in the region. We identified several important questions on the nature of the deer–coyote relationship in the East.

  9. Managing weather and climate risks to agriculture in North America, Central America and the Caribbean

    Directory of Open Access Journals (Sweden)

    Harlan D. Shannon

    2015-12-01

    Full Text Available In recent decades, numerous weather- and climate-related natural disasters have impacted North America, Central America, and the Caribbean, repeatedly demonstrating how vulnerable local agriculture is to extreme episodic events. Given this recent history, and expectations that the frequency and intensity of some episodic events will increase with climate change, it is becoming increasingly important for farmers to proactively manage weather and climate risks to agriculture to protect their livelihoods. Some farmers in this region already apply various strategies to help reduce weather and climate risks and uncertainties, including farming in multiple locations, diversifying crops and varieties, seeking alternative sources of income, and purchasing crop insurance. Such efforts often help farmers maintain a more stable income while also protecting and preserving the productivity of the land. Other farmers, however, have failed to implement basic risk management strategies despite the clear benefits. Reasons for these failures can be attributed to inadequate farmer education and training, a lack of tools to help facilitate the practical application of risk management concepts, and poor communications between the agrometeorological and farming communities. The agrometeorological community can help overcome these obstacles by building upon existing efforts that have successfully educated farmers about weather and climate risks to agriculture and have equipped farmers with the data, tools, and applications necessary to manage these risks. Farmer input is critical to preparing effective educational and training materials and developing user-friendly risk management tools. The agrometeorological community should solicit input from farmers regularly to ensure that farmers are obtaining the information necessary to effectively manage weather and climate risks to agriculture.

  10. A synthesis of ENSO effects on drylands in Australia, North America and South America

    Directory of Open Access Journals (Sweden)

    M. Holmgren

    2006-01-01

    Full Text Available Fundamentally, El Niño Southern Oscillation (ENSO is a climatic and oceanographic phenomenon, but it has profound effects on terrestrial ecosystems. Although the ecological effects of ENSO are becoming increasingly known from a wide range of terrestrial ecosystems (Holmgren et al., 2001, their impacts have been more intensively studied in arid and semiarid systems. In this brief communication, we summarize the main conclusions of a recent symposium on the effects of ENSO in these ecosystems, which was convened as part of the First Alexander von Humboldt International Conference on the El Niño Phenomenon and its Global Impact, in Guayaquil, Ecuador, from 16–20 May 2005. Participants in the symposium shared results and perspectives from research conducted in North and South America and Australia, regions where the ecological effects of ENSO have been studied in depth. Although the reports covered a wide array of organisms and ecological systems (Fig. 1, a recurring theme was the strong increase in rainfall associated with ENSO events in dry ecosystems (during the El Niño phase of the oscillation in the Americas and the La Niña phase in Australia. Because inter-annual variability in precipitation is such a strong determinant of productivity in arid and semiarid ecosystems, increased ENSO rainfall is crucial for plant recruitment, productivity and diversity in these ecosystems. Several long-term studies show that this pulse in primary productivity causes a subsequent increase in herbivores, followed by an increase in carnivores, with consequences for changes in ecosystem structure and functioning that can be quite complex.

  11. A synthesis of ENSO effects on drylands in Australia, North America and South America

    Science.gov (United States)

    Holmgren, M.; Stapp, P.; Dickman, C. R.; Gracia, C.; Graham, S.; Gutiérrez, J. R.; Hice, C.; Jaksic, F.; Kelt, D. A.; Letnic, M.; Lima, M.; López, B. C.; Meserve, P. L.; Milstead, W. B.; Polis, G. A.; Previtali, M. A.; Richter, M.; Sabaté, S.; Squeo, F. A.

    2006-01-01

    Fundamentally, El Niño Southern Oscillation (ENSO) is a climatic and oceanographic phenomenon, but it has profound effects on terrestrial ecosystems. Although the ecological effects of ENSO are becoming increasingly known from a wide range of terrestrial ecosystems (Holmgren et al., 2001), their impacts have been more intensively studied in arid and semiarid systems. In this brief communication, we summarize the main conclusions of a recent symposium on the effects of ENSO in these ecosystems, which was convened as part of the First Alexander von Humboldt International Conference on the El Niño Phenomenon and its Global Impact, in Guayaquil, Ecuador, from 16-20 May 2005. Participants in the symposium shared results and perspectives from research conducted in North and South America and Australia, regions where the ecological effects of ENSO have been studied in depth. Although the reports covered a wide array of organisms and ecological systems (Fig. 1), a recurring theme was the strong increase in rainfall associated with ENSO events in dry ecosystems (during the El Niño phase of the oscillation in the Americas and the La Niña phase in Australia). Because inter-annual variability in precipitation is such a strong determinant of productivity in arid and semiarid ecosystems, increased ENSO rainfall is crucial for plant recruitment, productivity and diversity in these ecosystems. Several long-term studies show that this pulse in primary productivity causes a subsequent increase in herbivores, followed by an increase in carnivores, with consequences for changes in ecosystem structure and functioning that can be quite complex.

  12. USGS Small-scale Dataset - Bathymetry of North America 200506 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Bathymetry of North America map layer shows depth ranges using colors. The image was derived from the National Geophysical Data Center's ETOPO2 elevation data,...

  13. USGS Small-scale Dataset - Bathymetric Shaded Relief of North America 200509 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Bathymetric Shaded Relief of North America map layer shows depth ranges using colors, with relief enhanced by shading. The image was derived from the National...

  14. Notes on Clavarioid fungi—IX. Addendum to Clavulinopsis in North America

    NARCIS (Netherlands)

    Petersen, Ronald H.

    1971-01-01

    This paper constitutes an addendum to a previous paper by the author on the genus Clavulinopsis in North America. One new species is described, Clavulinopsis subaustralis Petersen, and one new combination made, Clavulinopsis laeticolor f. coccineo-basalis (Joss.) Petersen.

  15. Color North America Shaded Relief – 1-Kilometer Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The North America Shaded Relief data were derived from the GTOPO30 elevation data. GTOPO30 is a global digital elevation model (DEM) with a horizontal grid spacing...

  16. Eelgrass (Zostera marina) Microsatellite DNA Data; Pacific Coast of North America, 2000-2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set contains genetic information collected from eelgrass (Zostera marina) populations along the Pacific coast of North America from Alaska to Baha...

  17. STUDIES ON RARE AND POORLY KNOWN LEECHES (ANNELIDA: HIRUDINEA: GLOSSIPHONIIDAE) IN EASTERN NORTH AMERICA

    Science.gov (United States)

    Three taxa within the leech family Glossiphoniidae, Actinobdella inequiannulata, Placobdella hollensis, and Theromyzon spp., though widespread in eastern North America, remain poorly known with respect to their biology and systematics. All three taxa have been collected in New E...

  18. 78 FR 14778 - Application to Export Electric Energy; Shell Energy North America (US), L.P.

    Science.gov (United States)

    2013-03-07

    ...Shell Energy North America (US), L.P. (Shell Energy) has applied to renew its authority to transmit electric energy from the United States to Mexico pursuant to section 202(e) of the Federal Power...

  19. 78 FR 14779 - Application to Export Electric Energy; Shell Energy North America (US), L.P.

    Science.gov (United States)

    2013-03-07

    ...Shell Energy North America (US), L.P. (Shell Energy) has applied to renew its authority to transmit electric energy from the United States to Canada pursuant to section 202(e) of the Federal Power...

  20. Corporate responsibility reporting of the largest forest industry companies in North America

    OpenAIRE

    Li, Ning

    2009-01-01

    Forest products marketing This exploratory study aims to analyze the CR reporting by eleven largest forest products companies in North America. Both annual reports and sustainability reports produced in year 2006 by eleven largest forest products companies in North America were chosen for this very study. To ensure the comparability of the results, the study adopts the similar variables in operationalizations by Routto (2008), who studied the CR reporting of European forest products compan...

  1. Emerging Themes in Residential Child and Youth Care Practice in North America

    OpenAIRE

    Garfat, Thom

    2003-01-01

    Child and Youth Care practice in North America is, as it should be, in constant evolution. A review of the literature, conversations about practice and participation in the activities of the field reveal certain treads or themes which reft.ect the state of the field at this particular point in time. This paper identifies and reft.ects on some of those that seem most relevant to contemporary Child and Youth Care practice in North America.

  2. Necrotizing Fasciitis Caused by Hypermucoviscous Klebsiella pneumoniae in a Filipino Female in North America

    OpenAIRE

    Ng, Daniel; Frazee, Brad

    2014-01-01

    Necrotizing fasciitis caused by Klebsiella pneumoniae has been described in Southeast Asia, but has only recently begun to emerge in North America. The hypermucoviscous strain of K. pneumoniae is a particularly virulent strain known to cause devastatingly invasive infections, including necrotizing fasciitis. Here we present the first known case of necrotizing fasciitis caused by hypermucoviscous K. pneumoniae in North America. [West J Emerg Med. 2015;16(1):–0.

  3. North America's net terrestrial carbon exchange with the atmosphere 1990–2009

    Directory of Open Access Journals (Sweden)

    A. W. King

    2014-07-01

    Full Text Available Scientific understanding of the global carbon cycle is required for developing national and international policy to mitigate fossil-fuel CO2 emissions by managing terrestrial carbon uptake. Toward that understanding and as a contribution to the REgional Carbon Cycle Assessment and Processes (RECCAP project, this paper provides a synthesis of net land–atmosphere CO2 exchange for North America over the period (1990–2009. This synthesis is based on results from three different methods: atmospheric inversion, inventory-based methods and terrestrial biosphere modeling. All methods indicate that the North America land surface was a sink for atmospheric CO2, with a net transfer from atmosphere to land. Estimates ranged from −890 to −280 Tg C yr−1, where the atmospheric inversion estimate forms the lower bound of that range (a larger land-sink and the inventory-based estimate the upper (a smaller land sink. Integrating across estimates, "best" estimates (i.e., measures of central tendency are −472 ± 281 Tg C yr−1 based on the mean and standard deviation of the distribution and −360 Tg C yr−1 (with an interquartile range of −496 to −337 based on the median. Considering both the fossil-fuel emissions source and the land sink, our analysis shows that North America was, however, a net contributor to the growth of CO2 in the atmosphere in the late 20th and early 21st century. The continent's CO2 source to sink ratio for this time period was likely in the range of 4 : 1 to 3 : 1.

  4. Past climate change and plant evolution in Western North America: a case study in Rosaceae.

    Directory of Open Access Journals (Sweden)

    Mats Töpel

    Full Text Available Species in the ivesioid clade of Potentilla (Rosaceae are endemic to western North America, an area that underwent widespread aridification during the global temperature decrease following the Mid-Miocene Climatic Optimum. Several morphological features interpreted as adaptations to drought are found in the clade, and many species occupy extremely dry habitats. Recent phylogenetic analyses have shown that the sister group of this clade is Potentilla section Rivales, a group with distinct moist habitat preferences. This has led to the hypothesis that the ivesioids (genera Ivesia, Horkelia and Horkeliella diversified in response to the late Tertiary aridification of western North America. We used phyloclimatic modeling and a fossil-calibrated dated phylogeny of the family Rosaceae to investigate the evolution of the ivesioid clade. We have combined occurrence- and climate data from extant species, and used ancestral state reconstruction to model past climate preferences. These models have been projected into paleo-climatic scenarios in order to identify areas where the ivesioids may have occurred. Our analysis suggests a split between the ivesioids and Potentilla sect. Rivales around Late Oligocene/Early Miocene (∼23 million years ago, Ma, and that the ivesioids then diversified at a time when summer drought started to appear in the region. The clade is inferred to have originated on the western slopes of the Rocky Mountains from where a westward range expansion to the Sierra Nevada and the coast of California took place between ∼12-2 Ma. Our results support the idea that climatic changes in southwestern North America have played an important role in the evolution of the local flora, by means of in situ adaptation followed by diversification.

  5. Mercury and methylmercury in aquatic sediment across western North America

    Science.gov (United States)

    Fleck, Jacob; Marvin-DiPasquale, Mark C.; Eagles-Smith, Collin A.; Ackerman, Joshua T.; Lutz, Michelle A; Tate, Michael T.; Alpers, Charles N.; Hall, Britt D.; Krabbenhoft, David P.; Eckley, Chris S.

    2016-01-01

    Large-scale assessments are valuable in identifying primary factors controlling total mercury (THg) and monomethyl mercury (MeHg) concentrations, and distribution in aquatic ecosystems. Bed sediment THg and MeHg concentrations were compiled for > 16,000 samples collected from aquatic habitats throughout the West between 1965 and 2013. The influence of aquatic feature type (canals, estuaries, lakes, and streams), and environmental setting (agriculture, forest, open-water, range, wetland, and urban) on THg and MeHg concentrations was examined. THg concentrations were highest in lake (29.3 ± 6.5 μg kg− 1) and canal (28.6 ± 6.9 μg kg− 1) sites, and lowest in stream (20.7 ± 4.6 μg kg− 1) and estuarine (23.6 ± 5.6 μg kg− 1) sites, which was partially a result of differences in grain size related to hydrologic gradients. By environmental setting, open-water (36.8 ± 2.2 μg kg− 1) and forested (32.0 ± 2.7 μg kg− 1) sites generally had the highest THg concentrations, followed by wetland sites (28.9 ± 1.7 μg kg− 1), rangeland (25.5 ± 1.5 μg kg− 1), agriculture (23.4 ± 2.0 μg kg− 1), and urban (22.7 ± 2.1 μg kg− 1) sites. MeHg concentrations also were highest in lakes (0.55 ± 0.05 μg kg− 1) and canals (0.54 ± 0.11 μg kg− 1), but, in contrast to THg, MeHg concentrations were lowest in open-water sites (0.22 ± 0.03 μg kg− 1). The median percent MeHg (relative to THg) for the western region was 0.7%, indicating an overall low methylation efficiency; however, a significant subset of data (n > 100) had percentages that represent elevated methylation efficiency (> 6%). MeHg concentrations were weakly correlated with THg (r2 = 0.25) across western North America. Overall, these results highlight the large spatial variability in sediment THg and MeHg concentrations throughout western North America and underscore the important roles that landscape and land

  6. Economics issues - nuclear power generation in North America

    International Nuclear Information System (INIS)

    The structure of the US utility industry is in transition. Political, social, and economic factors are contributing to a rapid shift from a monopoly structure (captive markets, cost-plus prices, negotiated rate of return on capital) to a highly competitive one (choices for customers, prices determined by the market place, earnings based on market price less cost). The rate of change has been accelerating. For example, what just two years ago would have been thought of as highly unlikely -- competition for the individual electric customer -- is now part of the plan in California and other states. In our view, technology is at the root of many of these structural changes with more to come. Yet another round of technological change is afoot, involving even more efficient gas turbines, new methods of utilizing transmission lines, distributed generation, and new opportunities for electricity use and service. It can be argued that the restructuring of the marketplace reflects, in some measure, anticipation for these advances. For the foreseeable future, nuclear energy will continue to play a significant role in the generating grid of North America. However, new nuclear generation will be held to standards of competition that are dictated by market forces, and by advances in competing technologies for base load generation. It is important to understand these forces, and devise a response which ensures that nuclear energy will continue to provide a viable, competitive, and environmentally superior option for generating electricity in the 21st century. The EPRI Nuclear Power program is focused on achieving these goals. (author)

  7. Proterozoic history of the midcontinent region of North America

    Science.gov (United States)

    Bickford, M. E.; van, W. R.; Zietz, Isidore

    1986-06-01

    Age and petrographic data from the buried basement of the midcontinent region of North America, integrated with information from exposed rocks and magnetic- and gravity-anomaly maps, allow much of the Proterozoic history of the region to be assembled. The Superior craton may be traced into the subsurface on the basis of characteristic magnetic patterns and limited age data. The region between the Superior craton and the Wyoming craton to the west is evidently underlain by southerly extension of the Trans-Hudson orogen of Canada. The Penokean orogen formed on the southern margin of the Superior craton 1890 1830 Ma, but is not inferred west of northwestern Iowa in the subsurface. Between 1780 and 1720 Ma, a major orogen developed along the southern margin of the continent and is exposed in Arizona and Colorado. These rocks are volcanogenic and, for the most part, juvenile additions to the crust; they can be traced beneath the plains as far as eastern Kansas and Nebraska. Another orogen formed farther to the south about 1700 1630 Ma and is exposed in southern Arizona and New Mexico; rocks of this age and type have beer, traced as far east as central Missouri but may extend as far as central Michigan. A major geophysical feature of the midcontinent is a system of northwest-trending magnetic and gravity anomalies in Missouri, Kansas, and Nebraska; the origin of these is not currently understood. The tectonic history of the midcontinent between 1480 and 1340 Ma was dominated by extensional formation of two widespread granite-rhyolite terranes that evidently were formed from, and overlie, the orogenic provinces. The older, formed 1450 1480 Ma, underlies the eastern midcontinent, whereas the younger, formed 1340 1400 Ma, underlies the southwestern midcontinent. The latest Proterozoic events were the formation of the midcontinent rift system and the collisional Grenville and Llano provinces about 1100 Ma.

  8. Knowledge exchange for climate adaptation planning in western North America

    Science.gov (United States)

    Garfin, Gregg; Orr, Barron

    2015-04-01

    In western North America, the combination of sustained drought, rapid ecosystem changes, and land use changes associated with urban population growth has motivated concern among ecosystem managers about the implications of future climate changes for the landscapes which they manage. Through literature review, surveys, and workshop discussions, we assess the process of moving from concern, to planning, to action, with an emphasis on questions, such as: What are the roles of boundary organizations in facilitating knowledge exchange? Which practices lead to effective interactions between scientists, decision-makers, and knowledge brokers? While there is no "one size fits all" science communication method, the co-production of science and policy by research scientists, science translators, and decision-makers, as co-equals, is a resource intensive, but effective practice for moving adaptation planning forward. Constructive approaches make use of alliances with early adopters and opinion leaders, and make strong communication links between predictions, impacts and solutions. Resource managers need information on the basics of regional climate variability and global climate change, region-specific projections of climate changes and impacts, frank discussion of uncertainties, and opportunities for candid exploration of these topics with peers and subject experts. Research scientists play critical roles in adaptation planning discussions, because they assist resource managers in clarifying the cascade of interactions leading to potential impacts and, importantly, because decision-makers want to hear the information straight from the scientists conducting the research, which bolsters credibility. We find that uncertainty, formerly a topic to avoided, forms the foundation for constructive progress in adaptation planning. Candid exploration of the array of uncertainties, including those due to modeling, institutional, policy and economic factors, with practitioners, science

  9. Predicting grizzly bear density in western North America.

    Directory of Open Access Journals (Sweden)

    Garth Mowat

    Full Text Available Conservation of grizzly bears (Ursus arctos is often controversial and the disagreement often is focused on the estimates of density used to calculate allowable kill. Many recent estimates of grizzly bear density are now available but field-based estimates will never be available for more than a small portion of hunted populations. Current methods of predicting density in areas of management interest are subjective and untested. Objective methods have been proposed, but these statistical models are so dependent on results from individual study areas that the models do not generalize well. We built regression models to relate grizzly bear density to ultimate measures of ecosystem productivity and mortality for interior and coastal ecosystems in North America. We used 90 measures of grizzly bear density in interior ecosystems, of which 14 were currently known to be unoccupied by grizzly bears. In coastal areas, we used 17 measures of density including 2 unoccupied areas. Our best model for coastal areas included a negative relationship with tree cover and positive relationships with the proportion of salmon in the diet and topographic ruggedness, which was correlated with precipitation. Our best interior model included 3 variables that indexed terrestrial productivity, 1 describing vegetation cover, 2 indices of human use of the landscape and, an index of topographic ruggedness. We used our models to predict current population sizes across Canada and present these as alternatives to current population estimates. Our models predict fewer grizzly bears in British Columbia but more bears in Canada than in the latest status review. These predictions can be used to assess population status, set limits for total human-caused mortality, and for conservation planning, but because our predictions are static, they cannot be used to assess population trend.

  10. Predicting grizzly bear density in western North America.

    Science.gov (United States)

    Mowat, Garth; Heard, Douglas C; Schwarz, Carl J

    2013-01-01

    Conservation of grizzly bears (Ursus arctos) is often controversial and the disagreement often is focused on the estimates of density used to calculate allowable kill. Many recent estimates of grizzly bear density are now available but field-based estimates will never be available for more than a small portion of hunted populations. Current methods of predicting density in areas of management interest are subjective and untested. Objective methods have been proposed, but these statistical models are so dependent on results from individual study areas that the models do not generalize well. We built regression models to relate grizzly bear density to ultimate measures of ecosystem productivity and mortality for interior and coastal ecosystems in North America. We used 90 measures of grizzly bear density in interior ecosystems, of which 14 were currently known to be unoccupied by grizzly bears. In coastal areas, we used 17 measures of density including 2 unoccupied areas. Our best model for coastal areas included a negative relationship with tree cover and positive relationships with the proportion of salmon in the diet and topographic ruggedness, which was correlated with precipitation. Our best interior model included 3 variables that indexed terrestrial productivity, 1 describing vegetation cover, 2 indices of human use of the landscape and, an index of topographic ruggedness. We used our models to predict current population sizes across Canada and present these as alternatives to current population estimates. Our models predict fewer grizzly bears in British Columbia but more bears in Canada than in the latest status review. These predictions can be used to assess population status, set limits for total human-caused mortality, and for conservation planning, but because our predictions are static, they cannot be used to assess population trend.

  11. Oral rabies vaccination in north america: opportunities, complexities, and challenges.

    Directory of Open Access Journals (Sweden)

    Dennis Slate

    Full Text Available Steps to facilitate inter-jurisdictional collaboration nationally and continentally have been critical for implementing and conducting coordinated wildlife rabies management programs that rely heavily on oral rabies vaccination (ORV. Formation of a national rabies management team has been pivotal for coordinated ORV programs in the United States of America. The signing of the North American Rabies Management Plan extended a collaborative framework for coordination of surveillance, control, and research in border areas among Canada, Mexico, and the US. Advances in enhanced surveillance have facilitated sampling of greater scope and intensity near ORV zones for improved rabies management decision-making in real time. The value of enhanced surveillance as a complement to public health surveillance was best illustrated in Ohio during 2007, where 19 rabies cases were detected that were critical for the formulation of focused contingency actions for controlling rabies in this strategically key area. Diverse complexities and challenges are commonplace when applying ORV to control rabies in wild meso-carnivores. Nevertheless, intervention has resulted in notable successes, including the elimination of an arctic fox (Vulpes lagopus rabies virus variant in most of southern Ontario, Canada, with ancillary benefits of elimination extending into Quebec and the northeastern US. Progress continues with ORV toward preventing the spread and working toward elimination of a unique variant of gray fox (Urocyon cinereoargenteus rabies in west central Texas. Elimination of rabies in coyotes (Canis latrans through ORV contributed to the US being declared free of canine rabies in 2007. Raccoon (Procyon lotor rabies control continues to present the greatest challenges among meso-carnivore rabies reservoirs, yet to date intervention has prevented this variant from gaining a broad geographic foothold beyond ORV zones designed to prevent its spread from the eastern US

  12. The later evolution of modern sport in Latin America: the North American influence.

    Science.gov (United States)

    Arbena, J L

    2001-01-01

    American impact on modern sports in Latin America overlaps geographically and chronologically with the European, especially British, impact. Principally baseball in the Caribbean basin, more recently basketball and volleyball across the hemisphere and occasionally American football in more limited areas illustrate a north-to-south movement executed by businessmen, educators, missionaries, military personnel, returning travelers (often students), sports entrepreneurs and television. Often initially supported by promoters of development within Latin America, this transfer has altered local recreational patterns and attracted Latin athletes to pursue careers in North America, provoking accusations of cultural imperialism and exploitation. PMID:18592684

  13. Characterization of low-pathogenicity H5N1 avian influenza viruses from North America

    Science.gov (United States)

    Spackman, Erica; Swayne, David E.; Suarez, David L.; Senne, Dennis A.; Pedersen, Janice C.; Killian, Mary Lea; Pasick, John; Handel, Katherine; Somanathan Pillai, Smitha; Lee, Chang-Won; Stallknecht, David; Slemons, Richard; Ip, Hon S.; Deliberto, Tom

    2007-01-01

    Wild-bird surveillance in North America for avian influenza (AI) viruses with a goal of early identification of the Asian H5N1 highly pathogenic AI virus has identified at least six low-pathogenicity H5N1 AI viruses between 2004 and 2006. The hemagglutinin (HA) and neuraminidase (NA) genes from all 6 H5N1 viruses and an additional 38 North American wild-bird-origin H5 subtype and 28 N1 subtype viruses were sequenced and compared with sequences available in GenBank by phylogenetic analysis. Both HA and NA were phylogenetically distinct from those for viruses from outside of North America and from those for viruses recovered from mammals. Four of the H5N1 AI viruses were characterized as low pathogenicity by standard in vivo pathotyping tests. One of the H5N1 viruses, A/MuteSwan/MI/451072-2/06, was shown to replicate to low titers in chickens, turkeys, and ducks. However, transmission of A/MuteSwan/MI/451072-2/06 was more efficient among ducks than among chickens or turkeys based on virus shed. The 50% chicken infectious dose for A/MuteSwan/MI/451072-2/06 and three other wild-waterfowl-origin H5 viruses were also determined and were between 105.3 and 107.5 50% egg infective doses. Finally, seven H5 viruses representing different phylogenetic clades were evaluated for their antigenic relatedness by hemagglutination inhibition assay, showing that the antigenic relatedness was largely associated with geographic origin. Overall, the data support the conclusion that North American H5 wild-bird-origin AI viruses are low-pathogenicity wild-bird-adapted viruses and are antigenically and genetically distinct from the highly pathogenic Asian H5N1 virus lineage.

  14. Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America

    Science.gov (United States)

    The book “Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America” summarizes published research in soil science and agronomy from various field experiments conducted in the soil-climatic/agro-ecological regions of the Northern Great Plains of North America....

  15. Genetic characterisation of Toxoplasma gondii in wildlife from North America revealed widespread and high prevalence of the fourth clonal type

    Science.gov (United States)

    Dubey, J.P.; Velmurugan, G.V.; Ragendran, C.; Yabsley, M.J.; Thomas, N.J.; Beckmen, K.B.; Sinnett, D.; Ruid, D.; Hart, J.; Fair, P.A.; McFee, W.E.; Shearn-Bochsler, V.; Kwok, O.C.H.; Ferreira, L.R.; Choudhary, S.; Faria, E.B.; Zhou, H.; Felix, T.A.; Su, C.

    2011-01-01

    Little is known of the genetic diversity of Toxoplasma gondii circulating in wildlife. In the present study wild animals, from the USA were examined for T. gondii infection. Tissues of naturally exposed animals were bioassayed in mice for isolation of viable parasites. Viable T. gondii was isolated from 31 animals including, to our knowledge for the first time, from a bald eagle (Haliaeetus leucocephalus), five gray wolves (Canis lupus), a woodrat (Neotoma micropus), and five Arctic foxes (Alopex lagopus). Additionally, 66 T. gondii isolates obtained previously, but not genetically characterised, were revived in mice. Toxoplasma gondii DNA isolated from these 97 samples (31+66) was characterised using 11 PCR-restriction fragment length polymorphism (RFLP) markers (SAG1, 5'- and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico). A total of 95 isolates were successfully genotyped. In addition to clonal Types II, and III, 12 different genotypes were found. These genotype data were combined with 74 T. gondii isolates previously characterised from wildlife from North America and a composite data set of 169 isolates comprised 22 genotypes, including clonal Types II, III and 20 atypical genotypes. Phylogenetic network analysis showed limited diversity with dominance of a recently designated fourth clonal type (Type 12) in North America, followed by the Type II and III lineages. These three major lineages together accounted for 85% of strains in North America. The Type 12 lineage includes previously identified Type A and X strains from sea otters. This study revealed that the Type 12 lineage accounts for 46.7% (79/169) of isolates and is dominant in wildlife of North America. No clonal Type I strain was identified among these wildlife isolates. These results suggest that T. gondii strains in wildlife from North America have limited diversity, with the occurrence of only a few major clonal types.

  16. Quantifying River Widths of North America from Satellite Imagery

    Science.gov (United States)

    Allen, G. H.; Pavelsky, T.; Miller, Z.

    2013-12-01

    River width is a fundamental predictor variable in many hydrologic, geomorphic, and biogeochemical models, yet current large-scale models rely on theoretical hydraulic geometry relationships that do not fully capture natural variability in river form. Here we present the first high-resolution dataset of long-term mean width of North American rivers wider than 30 m. The dataset contains 7.93 million georeferenced width measurements derived from Landsat TM and ETM+ imagery that were acquired when rivers were most likely to be at mean discharge. We built the dataset by developing an automated procedure that selects and downloads raw imagery, creates cloud-free normalized difference water index images, histogram balances and mosaics them together, and produces a water mask using a dynamic water-land threshold technique. We then visually inspected and corrected the mask for errors and used RivWidth software to calculate river width at each river centerline pixel. We validated our dataset using >1000 United States Geological Survey and Water Survey of Canada in situ gauge station measurements. Error analysis shows a robust relationship between the remotely sensed widths and in situ gauge measurements with an r 2 = 0.86 (Spearman's = 0.81) and a mean absolute error of 27.5 m. We find that North American river widths lie on logarithmic frequency curve with some notable exceptions at widths SWOT) satellite mission.

  17. Transpacific transport of ozone pollution and the effect of recent Asian emission increases on air quality in North America: an integrated analysis using satellite, aircraft, ozonesonde, and surface observations

    Directory of Open Access Journals (Sweden)

    L. Zhang

    2008-10-01

    Full Text Available We use an ensemble of aircraft, satellite, sonde, and surface observations for April–May 2006 (NASA/INTEX-B aircraft campaign to better understand the mechanisms for transpacific ozone pollution and its implications for North American air quality. The observations are interpreted with a global 3-D chemical transport model (GEOS-Chem. OMI NO2 satellite observations constrain Asian anthropogenic NOx emissions and indicate a factor of 2 increase from 2000 to 2006 in China. Satellite observations of CO from AIRS and TES indicate two major events of Asian transpacific pollution during INTEX-B. Correlation between TES CO and ozone observations shows evidence for transpacific ozone pollution. The semi-permanent Pacific High and Aleutian Low cause splitting of transpacific pollution plumes over the Northeast Pacific. The northern branch circulates around the Aleutian Low and has little impact on North America. The southern branch circulates around the Pacific High and some of that air impacts western North America. Both aircraft measurements and model results show sustained ozone production driven by peroxyacetylnitrate (PAN decomposition in the southern branch, roughly doubling the transpacific influence from ozone produced in the Asian boundary layer. Model simulation of ozone observations at Mt. Bachelor Observatory in Oregon (2.7 km altitude indicates a mean Asian ozone pollution contribution of 9±3 ppbv to the mean observed concentration of 54 ppbv, reflecting mostly an enhancement in background ozone rather than episodic Asian plumes. Asian pollution enhanced surface ozone concentrations by 5–7 ppbv over western North America in spring 2006. The 2000–2006 rise in Asian anthropogenic emissions increased this influence by 1–2 ppbv.

  18. Transpacific transport of ozone pollution and the effect of recent Asian emission increases on air quality in North America: an integrated analysis using satellite, aircraft, ozonesonde, and surface observations

    Directory of Open Access Journals (Sweden)

    L. Zhang

    2008-04-01

    Full Text Available We use an ensemble of aircraft, satellite, sonde, and surface observations for April–May 2006 (NASA/INTEX-B aircraft campaign to better understand the mechanisms for transpacific ozone pollution and its implications for North American air quality. The observations are interpreted with a global 3-D chemical transport model (GEOS-Chem. OMI NO2 satellite observations constrain Asian anthropogenic NOx emissions and indicate a factor of 2 increase from 2000 to 2006 in China. Satellite observations of CO from AIRS and TES indicate two major events of Asian transpacific pollution during INTEX-B. Correlation between TES CO and ozone observations shows evidence for transpacific ozone pollution. The semi-permanent Pacific High and Aleutian Low cause splitting of transpacific pollution plumes over the Northeast Pacific. The northern branch circulates around the Aleutian Low and has little impact on North America. The southern branch circulates around the Pacific High and impacts western North America. Both aircraft measurements and model results show sustained ozone production driven by peroxyacetylnitrate (PAN decomposition in the southern branch, roughly doubling the transpacific influence from ozone produced in the Asian boundary layer. Model simulation of ozone observations at Mt. Bachelor Observatory in Oregon (2.7 km altitude indicates a mean Asian ozone pollution contribution of 9±3 ppbv to the mean observed concentration of 54 ppbv, reflecting mostly an enhancement in background ozone rather than episodic Asian plumes. Asian pollution enhanced surface ozone concentrations by 5–7 ppbv over western North America in spring 2006. The 2000–2006 rise in Asian anthropogenic emissions increased the influence by 1–2 ppbv.

  19. North American Water Program (NAWP): A Vision to Address North America's Freshwater Sustainability Challenges

    Science.gov (United States)

    Belvedere, D. R.; Houser, P. R.; Schiffer, R. A.; Entin, J. K.

    2013-12-01

    Dramatically changing climates has had an indelible impact on North America's water crisis; the rapid melting of glaciers has profound implications for the sustainability of Canada's rivers. However, projective increases in water demand from increasing population, industrial energy, and agriculture needs may have four times more impact on the water supply-demand imbalance than climate change. Reliable prediction of hydrologic change and extremes is of critical importance for policy and decision makers to adapt to these future water challenges. However, the models that we use to understand and forecast water availability, flooding, and drought are simply not up to the task of addressing our most pressing societal issues and national security. We need a decisive and coordinative effort to systematically improve water cycle prediction skill, coupled with reliable methodologies to translate those predictions into actionable water supply and quality information to support sustainable water management - this is a primary motivation for the proposed North American Water Program (NAWP). To decisively address these challenges, we recommend that NAWP coalesce an interdisciplinary, international and interagency effort to make significant contributions to continental-to-decision-scale hydroclimate science and solutions. By entraining, integrating and coordinating the vast array of interdisciplinary observationable and prediction resources available, NAWP will significantly advance skill in predicting, assessing, and managing variability and changes in North American water resources, as an integral part of the global climate system. We adopt three challenges to organize NAWP efforts. The first deals with developing a scientific basis and tools for mitigating and adapting to changes in the water supply-demand balance. The second challenge is benchmarking; to use incomplete and uncertain observations to assess water storage and quality dynamics, and to characterize the

  20. Lithospheric Signature of Paleorifts in Cratonal Europe and North America

    Science.gov (United States)

    Keller, G. R.; Stephenson, R. A.; Mickus, K. L.

    2002-12-01

    Southwestern North America and Central Europe share many aspects of their Neoproterozoic and Phanerozoic tectonic evolution. In particular, the break-up of late Precambrian supercontinent created the continental blocks called Laurentia and Baltica. Passive margins developed during and after the rifting that formed these continents, and these margins were deformed by Paleozoic orogenies (Appalachian-Ouachita; Caledonian-Variscan respectively). Our group has studied the Ouachita orogeny that affected southern Laurentia for many years and has recently had the opportunity to study Central Europe by participating in several large seismic experiments. The results of the POLONAISE' 97 experiment delineated the rifted margin of Baltica, and we interpret it to be quite similar to crustal models we have developed for the Ouachita margin. For example, the Holy Cross Mountains in southern Poland exposed a crustal block that is similar to the Devil's River uplift in west Texas. The Polish basin contains a thick pre-Permian section similar to that observed along the Ouachita orogenic belt that is overlain by a Permian and younger sequence that is analogous to the Gulf Coast sequence. Both the Variscan orogeny in Central Europe and the Ouachita orogeny appear to be the result of soft collisions that have left the pre-orogenic rifted margins largely intact. In terms of continental tectonics, rifts that do not succeed in breaking a continent apart are sometimes referred to as having "failed". These failed rifts usually are the sites of post-rift sedimentation that contain important records of continental evolution and prolific petroleum resources. During the past 15 years, a number of studies have shown that the modification of the lithosphere (most evidence is actually for the crust) in failed rifts takes on many forms, is highly variable, and is often very substantial. Although semantic arguments are seldom productive, these results call into question any perception that these

  1. Meta-analysis of the effects of laidlomycin propionate, fed alone or in combination with chlortetracycline, compared with monensin sodium, fed alone or in combination with tylosin, on growth performance, health, and carcass outcomes in finishing steers in North America.

    Science.gov (United States)

    Cernicchiaro, N; Corbin, M; Quinn, M; Prouty, F; Branine, M; Renter, D G

    2016-04-01

    The objective of this research was to use data from multiple studies to comprehensively quantify the effects of feeding 1) laidlomycin propionate (LP), alone and/or in combination with chlortetracycline, compared with 2) monensin sodium (MS), alone and/or in combination with tylosin, at commercially approved dosages, on ADG, DMI, feed efficiency (FE), mortality, and carcass characteristics (HCW and liver abscesses). A secondary objective was to explore potential sources of heterogeneity among the comparative effectiveness studies. A systematic review of peer-reviewed literature and industry reports was used to identify studies that included direct comparisons of these treatments in finishing steers in North America. Random-effects meta-analysis models of performance, carcass, and health-related outcomes were fitted with extracted data, consisting of a total of 17 data sets comprising a total of 135 pens and 13,603 steers. Results showed that pens of steers fed LP had increased ADG (live and carcass adjusted), DMI, and HCW compared with those fed monensin ( 0.05) were identified for FE or for health-related outcomes (overall and cause-specific mortality). There was a substantial amount of heterogeneity in outcomes among studies, and when pen size and type of production setting were included in mixed-effects meta-regression models, they accounted for only a small proportion of the between-study heterogeneity found in the meta-analysis models. Therefore, caution should be exercised when interpreting summary estimates in the presence of substantial heterogeneity. However, these results provide comprehensive information on the comparative effects of different ionophores across multiple studies and multiple years, states, and production settings. These unique results can enable quantitative and informed decisions by potential end users of these feed additives that are widely used in the U.S. beef industry for reducing the costs of beef production through enhanced cattle

  2. Sex difference in blood pressure among South Asian diaspora in Europe and North America and the role of BMI: a meta-analysis

    NARCIS (Netherlands)

    J.S.L. de Munter; C. Agyemang; I.G. van Valkengoed; R. Bhopal; K. Stronks

    2011-01-01

    It is unclear whether the sex difference that is known to occur in blood pressure (BP) is similar in some South Asian populations. This study presents a meta-analysis of the sex difference in BP, hypertension and the role of body mass index (BMI) in South Asian diaspora compared with populations of

  3. North America's net terrestrial CO2 exchange with the atmosphere 1990-2009

    Science.gov (United States)

    King, A. W.; Andres, R. J.; Davis, K. J.; Hafer, M.; Hayes, D. J.; Huntzinger, D. N.; de Jong, B.; Kurz, W. A.; McGuire, A. D.; Vargas, R.; Wei, Y.; West, T. O.; Woodall, C. W.

    2015-01-01

    Scientific understanding of the global carbon cycle is required for developing national and international policy to mitigate fossil fuel CO2 emissions by managing terrestrial carbon uptake. Toward that understanding and as a contribution to the REgional Carbon Cycle Assessment and Processes (RECCAP) project, this paper provides a synthesis of net land-atmosphere CO2 exchange for North America (Canada, United States, and Mexico) over the period 1990-2009. Only CO2 is considered, not methane or other greenhouse gases. This synthesis is based on results from three different methods: atmospheric inversion, inventory-based methods and terrestrial biosphere modeling. All methods indicate that the North American land surface was a sink for atmospheric CO2, with a net transfer from atmosphere to land. Estimates ranged from -890 to -280 Tg C yr-1, where the mean of atmospheric inversion estimates forms the lower bound of that range (a larger land sink) and the inventory-based estimate using the production approach the upper (a smaller land sink). This relatively large range is due in part to differences in how the approaches represent trade, fire and other disturbances and which ecosystems they include. Integrating across estimates, "best" estimates (i.e., measures of central tendency) are -472 ± 281 Tg C yr-1 based on the mean and standard deviation of the distribution and -360 Tg C yr-1 (with an interquartile range of -496 to -337) based on the median. Considering both the fossil fuel emissions source and the land sink, our analysis shows that North America was, however, a net contributor to the growth of CO2 in the atmosphere in the late 20th and early 21st century. With North America's mean annual fossil fuel CO2 emissions for the period 1990-2009 equal to 1720 Tg C yr-1 and assuming the estimate of -472 Tg C yr-1 as an approximation of the true terrestrial CO2 sink, the continent's source : sink ratio for this time period was 1720:472, or nearly 4:1.

  4. North America's net terrestrial CO2 exchange with the atmosphere 1990–2009

    Science.gov (United States)

    King, A.W.; Andres, R.J.; Davis, K.J.; Hafer, M.; Hayes, D.J.; Huntzinger, Deborah N.; de Jong, Bernardus; Kurz, W.A.; McGuire, Anthony; Vargas, Rodrigo I.; Wei, Y.; West, Tristram O.; Woodall, Christopher W.

    2015-01-01

    Scientific understanding of the global carbon cycle is required for developing national and international policy to mitigate fossil fuel CO2 emissions by managing terrestrial carbon uptake. Toward that understanding and as a contribution to the REgional Carbon Cycle Assessment and Processes (RECCAP) project, this paper provides a synthesis of net land–atmosphere CO2 exchange for North America (Canada, United States, and Mexico) over the period 1990–2009. Only CO2 is considered, not methane or other greenhouse gases. This synthesis is based on results from three different methods: atmospheric inversion, inventory-based methods and terrestrial biosphere modeling. All methods indicate that the North American land surface was a sink for atmospheric CO2, with a net transfer from atmosphere to land. Estimates ranged from −890 to −280 Tg C yr−1, where the mean of atmospheric inversion estimates forms the lower bound of that range (a larger land sink) and the inventory-based estimate using the production approach the upper (a smaller land sink). This relatively large range is due in part to differences in how the approaches represent trade, fire and other disturbances and which ecosystems they include. Integrating across estimates, "best" estimates (i.e., measures of central tendency) are −472 ± 281 Tg C yr−1 based on the mean and standard deviation of the distribution and −360 Tg C yr−1 (with an interquartile range of −496 to −337) based on the median. Considering both the fossil fuel emissions source and the land sink, our analysis shows that North America was, however, a net contributor to the growth of CO2 in the atmosphere in the late 20th and early 21st century. With North America's mean annual fossil fuel CO2 emissions for the period 1990–2009 equal to 1720 Tg C yr−1 and assuming the estimate of −472 Tg C yr−1 as an approximation of the true terrestrial CO2 sink, the continent's source : sink ratio for this time period was

  5. Genomic and Evolutionary Analysis of Two Salmonella enterica Serovar Kentucky Sequence Types Isolated from Bovine and Poultry Sources in North America

    Science.gov (United States)

    Haley, Bradd J.; Kim, Seon Woo; Pettengill, James; Luo, Yan; Karns, Jeffrey S.; Van Kessel, Jo Ann S.

    2016-01-01

    Salmonella enterica subsp. enterica serovar Kentucky is frequently isolated from healthy poultry and dairy cows and is occasionally isolated from people with clinical disease. A genomic analysis of 119 isolates collected in the United States from dairy cows, ground beef, poultry and poultry products, and human clinical cases was conducted. Results of the analysis demonstrated that the majority of poultry and bovine-associated S. Kentucky were sequence type (ST) 152. Several bovine-associated (n = 3) and food product isolates (n = 3) collected from the United States and the majority of human clinical isolates were ST198, a sequence type that is frequently isolated from poultry and occasionally from human clinical cases in Northern Africa, Europe and Southeast Asia. A phylogenetic analysis indicated that both STs are more closely related to other Salmonella serovars than they are to each other. Additionally, there was strong evidence of an evolutionary divergence between the poultry-associated and bovine-associated ST152 isolates that was due to polymorphisms in four core genome genes. The ST198 isolates recovered from dairy farms in the United States were phylogenetically distinct from those collected from human clinical cases with 66 core genome SNPs differentiating the two groups, but more isolates are needed to determine the significance of this distinction. Identification of S. Kentucky ST198 from dairy animals in the United States suggests that the presence of this pathogen should be monitored in food-producing animals. PMID:27695032

  6. A Ceratopsian Dinosaur from the Lower Cretaceous of Western North America, and the Biogeography of Neoceratopsia.

    Directory of Open Access Journals (Sweden)

    Andrew A Farke

    Full Text Available The fossil record for neoceratopsian (horned dinosaurs in the Lower Cretaceous of North America primarily comprises isolated teeth and postcrania of limited taxonomic resolution, hampering previous efforts to reconstruct the early evolution of this group in North America. An associated cranium and lower jaw from the Cloverly Formation (?middle-late Albian, between 104 and 109 million years old of southern Montana is designated as the holotype for Aquilops americanus gen. et sp. nov. Aquilops americanus is distinguished by several autapomorphies, including a strongly hooked rostral bone with a midline boss and an elongate and sharply pointed antorbital fossa. The skull in the only known specimen is comparatively small, measuring 84 mm between the tips of the rostral and jugal. The taxon is interpreted as a basal neoceratopsian closely related to Early Cretaceous Asian taxa, such as Liaoceratops and Auroraceratops. Biogeographically, A. americanus probably originated via a dispersal from Asia into North America; the exact route of this dispersal is ambiguous, although a Beringian rather than European route seems more likely in light of the absence of ceratopsians in the Early Cretaceous of Europe. Other amniote clades show similar biogeographic patterns, supporting an intercontinental migratory event between Asia and North America during the late Early Cretaceous. The temporal and geographic distribution of Upper Cretaceous neoceratopsians (leptoceratopsids and ceratopsoids suggests at least intermittent connections between North America and Asia through the early Late Cretaceous, likely followed by an interval of isolation and finally reconnection during the latest Cretaceous.

  7. First detection of bat white-nose syndrome in western North America

    Science.gov (United States)

    Lorch, Jeffrey M.; Palmer, Jonathan M.; Lindner, Daniel L.; Ballmann, Anne; George, Kyle; Griffin, Kathryn M.; Knowles, Susan N.; Huckabee, John R; Haman, Katherine H; Anderson, Christopher D.; Becker, Penny A; Buchanan, Joseph B.; Foster, Jeffrey T.; Blehert, David

    2016-01-01

    White-nose syndrome (WNS) is an emerging fungal disease of bats caused byPseudogymnoascus destructans. Since it was first detected near Albany, NY, in 2006, the fungus has spread across eastern North America, killing unprecedented numbers of hibernating bats. The devastating impacts of WNS on Nearctic bat species are attributed to the likely introduction ofP. destructans from Eurasia to naive host populations in eastern North America. Since 2006, the disease has spread in a gradual wavelike pattern consistent with introduction of the pathogen at a single location. Here, we describe the first detection of P. destructans in western North America in a little brown bat (Myotis lucifugus) from near Seattle, WA, far from the previously recognized geographic distribution of the fungus. Whole-genome sequencing and phylogenetic analyses indicated that the isolate of P. destructans from Washington grouped with other isolates of a presumed clonal lineage from the eastern United States. Thus, the occurrence of P. destructans in Washington does not likely represent a novel introduction of the fungus from Eurasia, and the lack of intensive surveillance in the western United States makes it difficult to interpret whether the occurrence of P. destructans in the Pacific Northwest is disjunct from that in eastern North America. Although there is uncertainty surrounding the impacts of WNS in the Pacific Northwest, the presence of the pathogen in western North America could have major consequences for bat conservation.

  8. Climate change in our backyards: the reshuffling of North America's winter bird communities.

    Science.gov (United States)

    Princé, Karine; Zuckerberg, Benjamin

    2015-02-01

    Much of the recent changes in North American climate have occurred during the winter months, and as result, overwintering birds represent important sentinels of anthropogenic climate change. While there is mounting evidence that bird populations are responding to a warming climate (e.g., poleward shifts) questions remain as to whether these species-specific responses are resulting in community-wide changes. Here, we test the hypothesis that a changing winter climate should favor the formation of winter bird communities dominated by warm-adapted species. To do this, we quantified changes in community composition using a functional index--the Community Temperature Index (CTI)--which measures the balance between low- and high-temperature dwelling species in a community. Using data from Project FeederWatch, an international citizen science program, we quantified spatiotemporal changes in winter bird communities (n = 38 bird species) across eastern North America and tested the influence of changes in winter minimum temperature over a 22-year period. We implemented a jackknife analysis to identify those species most influential in driving changes at the community level and the population dynamics (e.g., extinction or colonization) responsible for these community changes. Since 1990, we found that the winter bird community structure has changed with communities increasingly composed of warm-adapted species. This reshuffling of winter bird communities was strongest in southerly latitudes and driven primarily by local increases in abundance and regional patterns of colonization by southerly birds. CTI tracked patterns of changing winter temperature at different temporal scales ranging from 1 to 35 years. We conclude that a shifting winter climate has provided an opportunity for smaller, southerly distributed species to colonize new regions and promote the formation of unique winter bird assemblages throughout eastern North America. PMID:25322929

  9. Spatiotemporal Patterns in Nest Box Occupancy by Tree Swallows Across North America

    Directory of Open Access Journals (Sweden)

    David Vleck

    2012-06-01

    Full Text Available Data from the North American Breeding Bird Survey (BBS suggest that populations of aerial insectivorous birds are declining, particularly in northeastern regions of the continent, and particularly since the mid-1980s. Species that use nest boxes, such as Tree Swallows (Tachycineta bicolor, may provide researchers with large data sets that better reveal finer-scale geographical patterns in population trends. We analyzed trends in occupancy rates for ca. 40,000 Tree Swallow nest-box-years from 16 sites across North America. The earliest site has been studied intensively since 1969 and the latest site since 2004. Nest box occupancy rates declined significantly at five of six (83% sites east of -78° W longitude, whereas occupancy rates increased significantly at four of ten sites (40% west of -78° W longitude. Decreasing box occupancy trends from the northeast were broadly consistent with aspects of a previous analysis of BBS data for Tree Swallows, but our finding of instances of increases in other parts of the continent are novel. Several questions remain, particularly with respect to causes of these broad-scale geographic changes in population densities of Tree Swallows. The broad geographic patterns are consistent with a hypothesis of widespread changes in climate on wintering, migratory, or breeding areas that in turn may differentially affect populations of aerial insects, but other explanations are possible. It is also unclear whether these changes in occupancy rates reflect an increase or decrease in overall populations of Tree Swallows. Regardless, important conservation steps will be to unravel causes of changing populations of aerial insectivores in North America.

  10. Standing and Travelling Wave Contributions to the Persistent Ridge-Trough Over North America During Winter 2013/14

    Science.gov (United States)

    Watt-Meyer, O.; Kushner, P. J.

    2015-12-01

    The winter season over North America during 2013/14 was dominated by a persistent ridge-trough that brought warm and dry conditions to the southwestern U.S., and markedly cold temperatures to central and eastern North America [Wang et al., 2014; Hartmann, 2015]. In addition, several cold air outbreaks occurred during the winter season, the strongest of which was around 7 January 2014 and led to minimum daily temperature records being set at many weather stations including Atlanta, Austin, Chicago and New York [Screen et al., in press]. This study uses a novel decomposition of wave variability into standing and travelling components [Watt-Meyer and Kushner, 2015] to diagnose the anomalous circulation of the 2013/14 winter season. This spectral decomposition is an improvement on previous methods because it explicitly accounts for the covariance between standing and travelling waves, and because the real-space components of the signal can be easily reconstructed. An index representing the ridge-trough dipole is computed using mid-tropospheric heights and shown to be well correlated with surface temperatures over central and eastern North America. The contributions to this dipole index from standing waves, westward travelling waves, and eastward travelling waves are calculated. The analysis demonstrates that the cold air outbreak of 7 January 2014 was driven by a synoptic wave of record breaking amplitude intensifying a persistent background amplification of the typical ridge-trough structure seen during North American winter.

  11. Quality Control Methodology Of A Surface Wind Observational Database In North Eastern North America

    Science.gov (United States)

    Lucio-Eceiza, Etor E.; Fidel González-Rouco, J.; Navarro, Jorge; Conte, Jorge; Beltrami, Hugo

    2016-04-01

    This work summarizes the design and application of a Quality Control (QC) procedure for an observational surface wind database located in North Eastern North America. The database consists of 526 sites (486 land stations and 40 buoys) with varying resolutions of hourly, 3 hourly and 6 hourly data, compiled from three different source institutions with uneven measurement units and changing measuring procedures, instrumentation and heights. The records span from 1953 to 2010. The QC process is composed of different phases focused either on problems related with the providing source institutions or measurement errors. The first phases deal with problems often related with data recording and management: (1) compilation stage dealing with the detection of typographical errors, decoding problems, site displacements and unification of institutional practices; (2) detection of erroneous data sequence duplications within a station or among different ones; (3) detection of errors related with physically unrealistic data measurements. The last phases are focused on instrumental errors: (4) problems related with low variability, placing particular emphasis on the detection of unrealistic low wind speed records with the help of regional references; (5) high variability related erroneous records; (6) standardization of wind speed record biases due to changing measurement heights, detection of wind speed biases on week to monthly timescales, and homogenization of wind direction records. As a result, around 1.7% of wind speed records and 0.4% of wind direction records have been deleted, making a combined total of 1.9% of removed records. Additionally, around 15.9% wind speed records and 2.4% of wind direction data have been also corrected.

  12. Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean

    Science.gov (United States)

    Alerstam; Gudmundsson

    1999-12-22

    Bird migration and orientation at high latitudes are of special interest because of the difficulties associated with different compass systems in polar areas and because of the considerable differences between flight routes conforming to loxodromes (rhumblines) or orthodromes (great circle routes). Regular and widespread east-north-east migration of birds from the northern tundra of Siberia towards North America across the Arctic Ocean (without landmark influences) were recorded by ship-based tracking radar studies in July and August. Field observations indicated that waders, including species such as Phalaropusfulicarius and Calidris melanotos, dominated, but also terns and skuas may have been involved. Analysis of flight directions in relation to the wind showed that these movements are not caused by wind drift. Assuming possible orientation principles based on celestial or geomagnetic cues, different flight trajectories across the Arctic Ocean were calculated: geographical loxodromes, sun compass routes, magnetic loxodromes and magnetoclinic routes. The probabilities of these four alternatives are evaluated on the basis of both the availability of required orientation cues and the predicted flight paths. This evaluation supports orientation along sun compass routes. Because of the longitudinal time displacement sun compass routes show gradually changing compass courses in close agreement with orthodromes. It is suggested that an important migration link between Siberia and North American stopover sites 1000-2500km apart across the Arctic Ocean has evolved based on sun compass orientation along orthodrome-like routes. PMID:10693821

  13. Phylogeny of Cirsium spp. in North America: Host Specificity Does Not Follow Phylogeny

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    Tracey A. Bodo Slotta

    2012-10-01

    Full Text Available Weedy invasive Cirsium spp. are widespread in temperate regions of North America and some of their biological control agents have attacked native Cirsium spp. A phylogenetic tree was developed from DNA sequences for the internal transcribed spacer and external transcribed spacer regions from native and non-native Great Plains Cirsium spp. and other thistles to determine if host specificity follows phylogeny. The monophyly of Cirsium spp. and Carduus within the tribe Cardinae was confirmed with native North American and European lineages of the Cirsium spp. examined. We did not detect interspecific hybridization between the introduced invasive and the native North American Cirsium spp. Selected host-biological control agent interactions were mapped onto the phylogenic tree derived by maximum likelihood analysis to examine the co-occurrence of known hosts with biological control agents. Within Cirsium-Cardueae, the insect biological control agents do not associate with host phylogenetic lines. Thus, more comprehensive testing of species in host-specificity trials, rather than relying on a single representative of a given clade may be necessary; because the assumption that host-specificity follows phylogeny does not necessarily hold. Since the assumption does not always hold, it will also be important to evaluate ecological factors to provide better cues for host specificity.

  14. The climate of North America during the past 2,000 years reconstructed from pollen data

    Science.gov (United States)

    Ladd, Matthew; Viau, Andre; Gajewski, Konrad

    2013-04-01

    The temperature of the warmest month was reconstructed for the past 2,000 years using almost 750 pollen sites from the North American Pollen Database. The modern analogue technique (MAT)implemented using MATTOOLS was used to quantify paleoclimates using a modern pollen database with over 4,800 calibration sites from across North America. Across North America, both the Medieval Warm Period (MWP) and Little Ice Age (LIA) were cooler than the present (1961-1990 AD, and the MWP was warmer than the LIA over at least three ecoregions in North America. Regional time series from the forest-tundra, boreal, conifer-hardwood forest show positive anomalies up to 0.6 °C during the MWP and up to -0.3 °C during the LIA. The reconstructions from the Southwestern United States, arctic, prairie and mountain vegetation ecoregions are less reliable due to fewer available data. These reconstructed anomalies during the MWP and LIA are significant deviations from the long-term neoglacial cooling. There is evidence for a poleward shift of the summer Subtropical High Pressure system in the North Atlantic during the MWP. This reconstruction provides important insight into the climate for large regions of North America during the MWP which is precisely where data and reconstructions are needed to better understand the geographical extent of the climate anomalies of this time period. These pollen-based reconstructions are comparable to those based on tree-rings.

  15. Video analysis of the escape flight of Pileated Woodpecker Dryocopus pileatus: does the Ivory-billed Woodpecker Campephilus principalis persist in continental North America?

    Directory of Open Access Journals (Sweden)

    Collinson J Martin

    2007-03-01

    Full Text Available Abstract Background The apparent rediscovery of the Ivory-billed Woodpecker Campephilus principalis in Arkansas, USA, previously feared extinct, was supported by video evidence of a single bird in flight (Fitzpatrick et al, Science 2005, 308:1460–1462. Plumage patterns and wingbeat frequency of the putative Ivory-billed Woodpecker were said to be incompatible with the only possible confusion species native to the area, the Pileated Woodpecker Dryocopus pileatus. Results New video analysis of Pileated Woodpeckers in escape flights comparable to that of the putative Ivory-billed Woodpecker filmed in Arkansas shows that Pileated Woodpeckers can display a wingbeat frequency equivalent to that of the Arkansas bird during escape flight. The critical frames from the Arkansas video that were used to identify the bird as an Ivory-billed Woodpecker are shown to be equally, or more, compatible with the Pileated Woodpecker. Conclusion The identification of the bird filmed in Arkansas in April 2004 as an Ivory-billed Woodpecker is best regarded as unsafe. The similarities between the Arkansas bird and known Pileated Woodpeckers suggest that it was most likely a Pileated Woodpecker.

  16. Climate-driven trends in the occurrence of major floods across North America and Europe

    Science.gov (United States)

    Hodgkins, Glenn A.; Whitfield, Paul H.; Burn, Donald H.; Hannaford, Jamie; Renard, Benjamin; Stahl, Kerstin; Fleig, Anne K.; Madsen, Henrik; Mediero, Luis; Korhonen, Johanna; Murphy, Conor; Crochet, Philippe; Wilson, Donna

    2016-04-01

    long-term variability in the number of major floods, annual exceedances of 25-, 50-, and 100-year floods during the last 50 - 80 years are estimated for all study gauges across North America and Europe, and for smaller groups of gauges defined by catchment size, location, climate, flood threshold, and period of record. Trends are computed using logistic regression techniques, supported by a suite of methods used to test the assumptions used in the analysis. We also analyse relationships between major flood occurrence and atmosphere/ocean indices (the AMO, NAO, PDO and SOI). Our analysis finds no compelling evidence for consistent changes over time in major-flood occurrence across North America and Europe, indicating that generalizations about major-flood occurrence trends across large domains or a diversity of catchment types are ungrounded. There are in fact more significant relationships between major-flood occurrence and the AMO than between flood occurrence and time. Flood occurrence overall (based on data from all 1204 gauges in our study) increased from 1961 to 2010 but not significantly, driven primarily by European increases. Non-significant increases were also found overall from 1931 to 2010 (322 gauges) but driven primarily by North American increases. Flood occurrence increased and decreased (including some significant changes) for the various sub-groups of gauges. Overall this study demonstrates that past changes in major-flood occurrence are highly complex and future changes will be likewise. International hydrologic networks containing minimally altered catchments will play a key role in understanding these complexities.

  17. The Younger Dryas ET Impact Theory and Terminal Pleistocene Mammalian Extinctions in North America

    Science.gov (United States)

    Erlandson, J. M.; Kennett, D. J.; Kennett, J.; Braje, T.; Culleton, B.

    2007-05-01

    Despite decades of intensive study and debate, no consensus has been reached on what caused the extinction of North America's mammalian megafauna at the end of the Pleistocene. In a scholarly standoff, prominent scientists have shown that neither "human overkill" or "climate change" models adequately account for the patterns found in the paleontological and archaeological records of North America. The Younger Dryas ET Impact theory may dramatically alter this debate, adding a catastrophic trigger to help explain the rapid extinction of many large mammals about 12,900 years ago. New data suggest that an extraterrestrial impact focused in northern and eastern North America may have devastated the megafauna through: (1) direct mortality caused by the impacts shock wave, debris, and massive wildfires; (2) dramatic reduction of terrestrial food supplies, rapid climatic change, and ecological reorganization; and (3) coup-de-grace effects of surviving human populations rapidly expanding after the impact.

  18. Molecular evolution of epizootic hemorrhagic disease viruses in North America based on historical isolates using motif fingerprints.

    Science.gov (United States)

    Wilson, W C; Ruder, M G; Jasperson, D; Smith, T P L; Naraghi-Arani, P; Lenhoff, R; Stallknecht, D E; Valdivia-Granda, W A; Sheoran, D

    2016-08-01

    Epizootic hemorrhagic disease virus (EHDV) is an orbivirus of the Reoviridae family that has significant impact on wild and captive white-tailed deer. Although closely related to bluetongue virus that can cause disease in sheep and cattle, North American EHDV historically has not been associated with disease in cattle or sheep. Severe disease in cattle has been reported with other EHDV strains from East Asia and the Middle East. To understand the potential role of viral genetics in the epidemiology of epizootic hemorrhagic disease, a molecular characterization of North American EHDV strains from 1955 to 2012 was conducted via conventional phylogenetic analysis and a new classification approach using motif fingerprint patterns. Overall, this study indicates that the genetic make-up of EHDV populations in North America have slowly evolved over time. The data also suggested limited reassortment events between serotypes 1 and 2 and introduces a new analysis tool for more detailed sequence pattern analysis. PMID:27107856

  19. New elmisaurine specimens from North America and their relationship to the Mongolian Elmisaurus rarus

    Directory of Open Access Journals (Sweden)

    Gregory F. Funston

    2016-02-01

    Full Text Available New specimens from Canada confirm the presence of elmisaurines in North America and shed light on the relationship of Leptorhynchos elegans to Mongolian forms. These specimens have hindlimb elements previously unknown from elmisaurines in the Dinosaur Park Formation, including tibiae and pedal phalanges. Metatarsal anatomy is sufficiently different to merit a generic distinction from Elmisaurus rarus, and both can be distinguished from Caenagnathus collinsi Sternberg, 1940 and Chirostenotes pergracilis. Differences between these taxa include body size, degree of coossification of the tarsometatarsus, and development of cruciate ridges of the third metatarsal. Histological analysis confirms that these differences are not correlated with ontogenetic age of the specimens. The results support the informal separation of caenagnathids based on metatarsal structure, and allow comments on paleobiological differences between caenagnathids and oviraptorids.

  20. Composition and uses of anaerobic digestion derived biogas from wastewater treatment facilities in North America.

    Science.gov (United States)

    Lackey, Jillian C; Peppley, B; Champagne, P; Maier, A

    2015-08-01

    A study was conducted to determine the current knowledge of biogas production and its use at municipal wastewater treatment plants (WWTPs) across North America. Information was provided by municipal WWTPs across Canada and the US. It was determined that hydrogen sulfide (H2S) and silicon (Si) compounds had sufficient variability to be of concern. The only biogas production trend that could be identified was a possible seasonal relationship with sludge input and biogas production. Secondary analysis was performed to observe trends in biogas usage in urban areas larger than 150,000 in the US and 50,000 in Canada; 66% of facilities had anaerobic digestion systems and, of those, only 35% had an energy recovery system. Climatic, population, and socio-political influences on the trends were considered. The primary conclusion was that more data is required to perform significant analyses on biogas production and composition variation.

  1. High-resolution Neogene and Quaternary estimates of Nubia-Eurasia-North America Plate motion

    Science.gov (United States)

    DeMets, C.; Iaffaldano, G.; Merkouriev, S.

    2015-10-01

    Reconstructions of the history of convergence between the Nubia and Eurasia plates constitute an important part of a broader framework for understanding deformation in the Mediterranean region and the closing of the Mediterranean Basin. Herein, we combine high-resolution reconstructions of Eurasia-North America and Nubia-North America Plate motions to determine rotations that describe Nubia-Eurasia Plate motion at ˜1 Myr intervals for the past 20 Myr. We apply trans-dimensional hierarchical Bayesian inference to the Eurasia-North America and Nubia-North America rotation sequences in order to reduce noise in the newly estimated Nubia-Eurasia rotations. The noise-reduced rotation sequences for the Eurasia-North America and Nubia-North America Plate pairs describe remarkably similar kinematic histories since 20 Ma, consisting of relatively steady seafloor spreading from 20 to 8 Ma, ˜20 per cent opening-rate slowdowns at 8-6.5 Ma, and steady plate motion from ˜7 Ma to the present. Our newly estimated Nubia-Eurasia rotations predict that convergence across the central Mediterranean Sea slowed by ˜50 per cent and rotated anticlockwise after ˜25 Ma until 13 Ma. Motion since 13 Ma has remained relatively steady. An absence of evidence for a significant change in motion immediately before or during the Messinian Salinity Crisis at 6.3-5.6 Ma argues against a change in plate motion as its causative factor. The detachment of the Arabian Peninsula from Africa at 30-24 Ma may have triggered the convergence rate slowdown before 13 Ma; however, published reconstructions of Nubia-Eurasia motion for times before 20 Ma are too widely spaced to determine with confidence whether the two are correlated. A significant discrepancy between our new estimates of Nubia-Eurasia motion during the past few Myr and geodetic estimates calls for further investigation.

  2. Economic integration in North America: Formal, Informal and Spatial Aspects.

    OpenAIRE

    Proulx, P.P.

    1996-01-01

    An exemination of a series of indicators of economic integration in the western hemisphere (Canada-USA-Latin America) indicates that it is proceeding under the influence of formal trade agreements and informal forces including technological change, multinational firm rationalization and location strategies, etc.

  3. Summertime atmosphere-ocean preconditionings for the Bering Sea ice retreat and the following severe winters in North America

    Science.gov (United States)

    Nakanowatari, Takuya; Inoue, Jun; Sato, Kazutoshi; Kikuchi, Takashi

    2015-09-01

    Atmospheric responses to sea ice retreat in the Bering Sea have been linked to recent extreme winters in North America. We investigate the leading factor for the interannual variability of Bering sea ice area (SIA) in early winter (November-December), using canonical correlation analysis based on seasonally resolved atmosphere and ocean data for 1980-2014. We found that the 3-month leading (August-September) geopotential height at 500 hPa (Z500) in the Northern Hemisphere explains 29% of SIA variability. The spatial pattern of Z500 for positive (negative) sea ice anomalies is associated with negative (positive) anomalies over the Gulf of Alaska related to the Pacific transition (PT) pattern. The heat budget analysis indicates that summertime atmospheric conditions influence SIA through the ocean temperature anomalies of the Alaskan Coastal Current forced by atmospheric turbulent heat fluxes. The PT pattern highly correlates with convective precipitation in the western subtropical Pacific, implying that weakened subtropical forcing is the likely cause for the recent extreme winters in North America. Our results present a major factor for interannual variability in the Bering SIA, and further would contribute to the improvement of forecasting winter climate in North America.

  4. Gravity anomalies, plate tectonics and the lateral growth of Precambrian North America

    International Nuclear Information System (INIS)

    The widespread gravity coverage of North America provides a picture of the gross structural fabric of the continent via the trends of gravity anomalies. The structural picture so obtained reveals a mosaic of gravity trend domains, many of which correlate closely with structural provinces and orogenic terranes. The gravity trend map, interpreted in the light of plate-tectonic theory, thus provides a new perspective for examining the mode of assembly and growth of North America. Suture zones, palaeosubduction directions, and perhaps, contrasting tectonic histories may be identified using gravity patterns

  5. The southern edge of cratonic North America: Evidence from new magnetic satellite observations

    DEFF Research Database (Denmark)

    Purucker, M.; Mandea, M.; Hulot, G.;

    2002-01-01

    A global model is developed for both induced and remanent magnetizations in the terrestrial lithosphere. The model is compared with, and well-described by, Ørsted satellite observations. Interpretation of the observations over North America suggests that the large total field anomalies, associated...... with spherical harmonic degrees 15-26 and centered over Kentucky and the south-central United States, are the manifestations of the magnetic edges of the southern boundaries of cratonic North America. The techniques and models developed here may be of use in defining other cratonic boundaries....

  6. The southern edge of cratonic North America: Evidence from new satellite magnetometer observations

    DEFF Research Database (Denmark)

    Purucker, M.; Langlais, B.; Olsen, Nils;

    2002-01-01

    [1] A global model is developed for both induced and remanent magnetizations in the terrestrial lithosphere. The model is compared with, and well-described by, Orsted satellite observations. Interpretation of the observations over North America suggests that the large total field anomalies......, associated with spherical harmonic degrees 15-26 and centered over Kentucky and the south-central United States, are the manifestations of the magnetic edges of the southern boundaries of cratonic North America. The techniques and models developed here may be of use in defining other cratonic boundaries....

  7. Gravity anomalies, plate tectonics and the lateral growth of Precambrian North America

    Science.gov (United States)

    Thomas, M. D.; Grieve, R. A. F.; Sharpton, V. L.

    1988-01-01

    The widespread gravity coverage of North America provides a picture of the gross structural fabric of the continent via the trends of gravity anomalies. The structural picture so obtained reveals a mosaic of gravity trend domains, many of which correlate closely with structural provinces and orogenic terranes. The gravity trend map, interpreted in the light of plate-tectonic theory, thus provides a new perspective for examining the mode of assembly and growth of North America. Suture zones, palaeosubduction directions, and perhaps, contrasting tectonic histories may be identified using gravity patterns.

  8. Wind Powering America: The Next Steps in North Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Banks, Jennifer L. [North Carolina Solar Center; Scanlin, Dennis [Appalachian State University; Quinlan, Paul [North Carolina Sustainable Energy Association

    2013-06-18

    The goal of this project is to apply the WPA’s proactive outreach strategy to the problem of educating the public about the likely transmission infrastructure developments concomitant to the significant development of wind energy resources in North Carolina. Given the lead time to develop significant new transmission infrastructure (5-10 years), it is critical to begin this outreach work today, so that wind resources can be developed to adequately meet the 20% by 2030 goal in the mid- to long-term (10-20 years). The project team planned to develop a transmission infrastructure outreach campaign for North Carolina by: (1) convening a utility interest group (UIG) of the North Carolina Wind Working Group (NC WWG) consisting of electric utilities in the state and the Southeast; and (2) expanding outreach to local and state government officials in North Carolina.

  9. The Banded Elm Bark Beetle, Scolytus schevyrewi Semenov (Coleoptera, Curculionidae, Scolytinae in North America: a taxonomic review and modifications to the Wood (1982 key to the species of Scolytus Geoffroy in North and Central America

    Directory of Open Access Journals (Sweden)

    James LaBonte

    2010-09-01

    Full Text Available In 2003, an Asian bark beetle, Scolytus schevyrewi Semenov (Coleoptera: Curculionidae: Scolytinae, the banded elm bark beetle, was detected for the first time in North America. This paper modifies the Wood (1982 key to the species of Scolytus Geoffroy to enable identification of S. schevyrewi in North and Central America. Variation of diagnostic characters in S. schevyrewi is discussed.

  10. The Banded Elm Bark Beetle, Scolytus schevyrewi Semenov (Coleoptera, Curculionidae, Scolytinae) in North America: a taxonomic review and modifications to the Wood (1982) key to the species of Scolytus Geoffroy in North and Central America

    OpenAIRE

    James LaBonte

    2010-01-01

    Abstract In 2003, an Asian bark beetle, Scolytus schevyrewi Semenov (Coleoptera: Curculionidae: Scolytinae), the banded elm bark beetle, was detected for the first time in North America. This paper modifies the Wood (1982) key to the species of Scolytus Geoffroy to enable identification of Scolytus schevyrewi in North and Central America. Variation of diagnostic characters in Scolytus schevyrewi is discussed.

  11. Northeastern North America as a potential refugium for boreal forests in a warming climate.

    Science.gov (United States)

    D'Orangeville, L; Duchesne, L; Houle, D; Kneeshaw, D; Côté, B; Pederson, N

    2016-06-17

    High precipitation in boreal northeastern North America could help forests withstand the expected temperature-driven increase in evaporative demand, but definitive evidence is lacking. Using a network of tree-ring collections from 16,450 stands across 583,000 km(2) of boreal forests in Québec, Canada, we observe a latitudinal shift in the correlation of black spruce growth with temperature and reduced precipitation, from negative south of 49°N to largely positive to the north of that latitude. Our results suggest that the positive effect of a warmer climate on growth rates and growing season length north of 49°N outweighs the potential negative effect of lower water availability. Unlike the central and western portions of the continent's boreal forest, northeastern North America may act as a climatic refugium in a warmer climate.

  12. Ancient Analogs of ENSO-Like Moisture Anomaly Patterns Across North America

    Science.gov (United States)

    Stahle, D. W.; Burnette, D. J.; Cook, E. R.

    2014-12-01

    A tripole-like structure tends to develop in the latitudinal distribution of seasonal drought and wetness across North America during El Nino and La Nina extremes. Composite maps of instrumental and tree-ring reconstructed moisture indices during El Nino extremes nearly mirror the teleconnected moisture patterns during La Nina extremes, but the signs of the regional anomalies are reversed. During El Nino events wetness tends to prevail over the southwestern U.S. and northern Mexico, simultaneously with drought over Central America and the Pacific Northwest. Map congruence analysis was used to measure the similarity between the composite moisture anomaly map during 10 El Nino extremes and the continent-wide pattern of tree-ring reconstructed moisture during each year from 1400 to 2005. Map congruence was also computed using the composite moisture anomalies during La Nina extremes as the target (ENSO extremes defined using the extended Multivariate ENSO Index). The two congruence time series (El Nino vs La Nina-like) are far from the perfect inverse of one another (r = -0.36; p < 0.001; 1400-1979), but sub-decadal smoothing reveals interesting episodes of continental scale structure in the moisture field that may have arisen from multi-year cool and warm ENSO extremes over the past 600-years.

  13. An animated tectonic reconstruction of southwestern North America since 36 Ma

    OpenAIRE

    McQuarrie, Nadine; Wernicke, Brian P.

    2005-01-01

    We present tectonic reconstructions and an accompanying animation of deformation across the North America–Pacific plate boundary since 36 Ma. Intraplate deformation of southwestern North America was obtained through synthesis of kinematic data (amount, timing, and direction of displacement) along three main transects through the northern (40°N), central (36°N– 37°N), and southern (34°N) portions of the Basin and Range province. We combined these transects with...

  14. Common Ancestry of Borrelia burgdorferi Sensu Lato Strains from North America and Europe

    OpenAIRE

    Postic, D; Ras, N. Marti; Lane, R S; Humair, P.-F.; Wittenbrink, M. M.; Baranton, G

    1999-01-01

    Ten atypical European Borrelia burgdorferi sensu lato (Borrelia spp.) strains were genetically characterized, and the diversity was compared to that encountered among related Borrelia spp. from North America. Phylogenetic analyses of a limited region of the genome and of the whole genome extend existing knowledge about borrelial diversity reported earlier in Europe and the United States. Our results accord with the evidence that North American and European strains may have a common ancestry.

  15. Spatiotemporal patterns of mercury accumulation in lake sediments of western North America

    Science.gov (United States)

    Drevnick, Paul; Cooke, Colin A.; Barraza, Daniella; Blais, Jules M.; Coale, Kenneth; Cumming, Brian F.; Curtis, Chris; Das, Biplob; Donahue, William F.; Eagles-Smith, Collin A.; Engstrom, Daniel R.; Fitzgerald, William F.; Furl, Chad V.; Gray, John R.; Hall, Roland I.; Jackson, Togwell A.; Laird, Kathleen R.; Lockhart, W. Lyle; Macdonald, Robie W.; Mast, M. Alisa; Mathieu, Callie; Muir, Derek C.G.; Outridge, Peter; Reinemann, Scott; Rothenberg, Sarah E.; Ruiz-Fernandex, Ana Carolina; St. Louis, V.L.; Sanders, Rhea; Sanei, Hamed; Skierszkan, Elliott; Van Metre, Peter C.; Veverica, Timothy; Wiklund, Johan A.; Wolfe, Brent B.

    2016-01-01

    For the Western North America Mercury Synthesis, we compiled mercury records from 165 dated sediment cores from 138 natural lakes across western North America. Lake sediments are accepted as faithful recorders of historical mercury accumulation rates, and regional and sub-regional temporal and spatial trends were analyzed with descriptive and inferential statistics. Mercury accumulation rates in sediments have increased, on average, four times (4×) from 1850 to 2000 and continue to increase by approximately 0.2 μg/m2 per year. Lakes with the greatest increases were influenced by the Flin Flon smelter, followed by lakes directly affected by mining and wastewater discharges. Of lakes not directly affected by point sources, there is a clear separation in mercury accumulation rates between lakes with no/little watershed development and lakes with extensive watershed development for agricultural and/or residential purposes. Lakes in the latter group exhibited a sharp increase in mercury accumulation rates with human settlement, stabilizing after 1950 at five times (5×) 1850 rates. Mercury accumulation rates in lakes with no/little watershed development were controlled primarily by relative watershed size prior to 1850, and since have exhibited modest increases (in absolute terms and compared to that described above) associated with (regional and global) industrialization. A sub-regional analysis highlighted that in the ecoregion Northwestern Forest Mountains, <1% of mercury deposited to watersheds is delivered to lakes. Research is warranted to understand whether mountainous watersheds act as permanent sinks for mercury or if export of “legacy” mercury (deposited in years past) will delay recovery when/if emissions reductions are achieved.

  16. Prioritizing Zoonotic Diseases: Differences in Perspectives Between Human and Animal Health Professionals in North America.

    Science.gov (United States)

    Ng, V; Sargeant, J M

    2016-05-01

    Zoonoses pose a significant burden of illness in North America. Zoonoses represent an additional threat to public health because the natural reservoirs are often animals, particularly wildlife, thus eluding control efforts such as quarantine, vaccination and social distancing. As there are limited resources available, it is necessary to prioritize diseases in order to allocate resources to those posing the greatest public health threat. Many studies have attempted to prioritize zoonoses, but challenges exist. This study uses a quantitative approach, conjoint analysis (CA), to overcome some limitations of traditional disease prioritization exercises. We used CA to conduct a zoonoses prioritization study involving a range of human and animal health professionals across North America; these included epidemiologists, public health practitioners, research scientists, physicians, veterinarians, laboratory technicians and nurses. A total of 699 human health professionals (HHP) and 585 animal health professionals (AHP) participated in this study. We used CA to prioritize 62 zoonotic diseases using 21 criteria. Our findings suggest CA can be used to produce reasonable criteria scores for disease prioritization. The fitted models were satisfactory for both groups with a slightly better fit for AHP compared to HHP (84.4% certainty fit versus 83.6%). Human-related criteria were more influential for HHP in their decision to prioritize zoonoses, while animal-related criteria were more influential for AHP resulting in different disease priority lists. While the differences were not statistically significant, a difference of one or two ranks could be considered important for some individuals. A potential solution to address the varying opinions is discussed. The scientific framework for disease prioritization presented can be revised on a regular basis by updating disease criteria to reflect diseases as they evolve over time; such a framework is of value allowing diseases of

  17. A quantitative approach to the prioritization of zoonotic diseases in North America: a health professionals' perspective.

    Directory of Open Access Journals (Sweden)

    Victoria Ng

    Full Text Available BACKGROUND: Currently, zoonoses account for 58% to 61% of all communicable diseases causing illness in humans globally and up to 75% of emerging human pathogens. Although the impact of zoonoses on animal health and public health in North America is significant, there has been no published research involving health professionals on the prioritization of zoonoses in this region. METHODOLOGY/PRINCIPAL FINDINGS: We used conjoint analysis (CA, a well-established quantitative method in market research, to identify the relative importance of 21 key characteristics of zoonotic diseases for their prioritization in Canada and the US. Relative importance weights from the CA were used to develop a point-scoring system to derive a recommended list of zoonoses for prioritization in Canada and the US. Study participants with a background in epidemiology, public health, medical sciences, veterinary sciences and infectious disease research were recruited to complete the online survey (707 from Canada and 764 from the US. Hierarchical Bayes models were fitted to the survey data to derive CA-weighted scores for disease criteria. Scores were applied to 62 zoonotic diseases to rank diseases in order of priority. CONCLUSIONS/SIGNIFICANCE: We present the first zoonoses prioritization exercise involving health professionals in North America. Our previous study indicated individuals with no prior knowledge in infectious diseases were capable of producing meaningful results with acceptable model fits (79.4%. This study suggests health professionals with some knowledge in infectious diseases were capable of producing meaningful results with better-fitted models than the general public (83.7% and 84.2%. Despite more similarities in demographics and model fit between the combined public and combined professional groups, there was more uniformity across priority lists between the Canadian public and Canadian professionals and between the US public and US professionals. Our

  18. 75 FR 64306 - Shell Energy North America (US), LP; Notice of Institution of Proceeding and Refund Effective Date

    Science.gov (United States)

    2010-10-19

    ... Energy Regulatory Commission Shell Energy North America (US), LP; Notice of Institution of Proceeding and... U.S.C. 824e (2005), concerning the justness and reasonableness of Shell Energy North America (US), LP's market- based rate authority in the Central and Southwest balancing authority area. Shell...

  19. 75 FR 76037 - HAVI Logistics, North America a Subsidiary of HAVI Group, LP Including On-Site Leased Workers of...

    Science.gov (United States)

    2010-12-07

    ..., Bloomingdale, Illinois. The Notice was published in the Federal Register on September 21, 2010 (75 FR 57516... Employment and Training Administration HAVI Logistics, North America a Subsidiary of HAVI Group, LP Including... Logistics, North America, Lisle, IL; Amended Certification Regarding Eligibility To Apply for...

  20. 76 FR 16447 - Lafarge North America, Inc., a Subsidiary of Lafarge, Including On-Site Leased Workers From...

    Science.gov (United States)

    2011-03-23

    ... December 13, 2010 (75 FR 77668). At the request of the State agency, the Department reviewed the... Employment and Training Administration Lafarge North America, Inc., a Subsidiary of Lafarge, Including On..., applicable to workers of Lafarge North America, Inc., a subsidiary of Lafarge, Seattle, Washington....

  1. 77 FR 37956 - BMW of North America, LLC, a Subsidiary of BMW AG; Receipt of Petition for Decision of...

    Science.gov (United States)

    2012-06-25

    ... Register published on April 11, 2000, (65 FR 19477-78). The petition, supporting materials, and all... National Highway Traffic Safety Administration BMW of North America, LLC, a Subsidiary of BMW AG; Receipt... Administration, DOT. ACTION: Receipt of Petition. SUMMARY: BMW of North America, LLC,\\1\\ a subsidiary of BMW...

  2. 77 FR 63415 - BMW of North America, LLC, a Subsidiary of BMW AG, Receipt of Petition for Decision of...

    Science.gov (United States)

    2012-10-16

    ... Statement is available for review in the Federal Register published on April 11, 2000, (65 FR 19477-78). The... National Highway Traffic Safety Administration BMW of North America, LLC, a Subsidiary of BMW AG, Receipt... Administration, DOT. ACTION: Receipt of petition. SUMMARY: BMW North America, LLC,\\1\\ a subsidiary of BMW...

  3. 77 FR 56700 - BMW of North America, LLC, a Subsidiary of BMW AG, Receipt of Petition for Decision of...

    Science.gov (United States)

    2012-09-13

    ... Statement is available for review in the Federal Register published on April 11, 2000, (65 FR 19477-78). The... National Highway Traffic Safety Administration BMW of North America, LLC, a Subsidiary of BMW AG, Receipt... Administration, DOT. ACTION: Receipt of petition. SUMMARY: BMW of North America, LLC (BMW),\\1\\ a subsidiary...

  4. 78 FR 21189 - Petition for Exemption From the Vehicle Theft Prevention Standard; BMW of North America, LLC

    Science.gov (United States)

    2013-04-09

    ... the agency (58 FR 44872, dated August 25, 1993), NHTSA's review of the theft data for 10 General... Standard; BMW of North America, LLC AGENCY: National Highway Traffic Safety Administration (NHTSA... full the BMW of North America, LLC (BMW) petition for exemption of the X4 vehicle line in...

  5. 78 FR 43964 - BMW of North America, LLC, a Subsidiary of BMW AG, Grant of Petition for Decision of...

    Science.gov (United States)

    2013-07-22

    ... Register (77 FR 37956.) No comments were received. To view the petition and all supporting documents log... National Highway Traffic Safety Administration BMW of North America, LLC, a Subsidiary of BMW AG, Grant of... Administration, DOT. ACTION: Grant of petition. SUMMARY: BMW of North America, LLC \\1\\ a subsidiary of BMW...

  6. 78 FR 38799 - BMW of North America, LLC, a Subsidiary of BMW AG, Grant of Petition for Decision of...

    Science.gov (United States)

    2013-06-27

    ... a 30-day public comment period, on September 13, 2012 in the Federal Register (77 FR 56700). No... National Highway Traffic Safety Administration BMW of North America, LLC, a Subsidiary of BMW AG, Grant of... Administration, DOT. ACTION: Grant of Petition. SUMMARY: BMW of North America, LLC (BMW) \\1\\, a subsidiary of...

  7. 77 FR 39689 - Application To Export Electric Energy; IPR-GDF SUEZ Energy Marketing North America, Inc.

    Science.gov (United States)

    2012-07-05

    ... Application To Export Electric Energy; IPR-GDF SUEZ Energy Marketing North America, Inc. AGENCY: Office of... Marketing North America, Inc. (GSEMNA) has applied for authority to transmit electric energy from the United... by email to Christopher.Lawrence@hq.doe.gov . SUPPLEMENTARY INFORMATION: Exports of electricity...

  8. The Spanish Borderlands of North America: A Historiography.

    Science.gov (United States)

    Weber, David J.

    2000-01-01

    Provides an historiographic overview of the North American Spanish borderlands, focusing on changes and various topics, such as defending or attacking missionaries. Addresses what teachers can do who are in search of a point of entry into the borderlands literature. (CMK)

  9. Patterns of widespread decline in North America bumble bees

    Science.gov (United States)

    Declining abundance and range shifts of bumble bee (Bombus) species have been observed in Europe and Asia. However, the status of North America’s bumble bee species has been largely unstudied. Recent reports based on local or regional observations suggest that parallel declines are taking place in N...

  10. Science and Management of the Introduced Seagrass Zostera japonica in North America

    Science.gov (United States)

    Healthy seagrass is considered a prime indicator of estuarine ecosystem function. On the Pacific coast of North America, at least two congeners of Zostera occur: native Zostera marina, and introduced, Z. japonica. Z. japonica is considered “invasive” and therefore, ecologically...

  11. Temporal dynamics of woodpecker predation on the invasive emerald ash borer (Agrilus planipennis) in North America

    Science.gov (United States)

    Woodpeckers (Picidae) are among the most prevalent natural enemies attacking the invasive emerald ash borer (EAB), Agrilus planipennis Fairmaire, in North America, but there can be considerable variation in the levels of EAB predation on ash trees (Oleaceae: Fraxinus) within and between sites as wel...

  12. Thermal constraints on the emerald ash borer invasion of North America

    Science.gov (United States)

    DeSantis, R.; Moser, W. K.; Gormanson, D. D.; Bartlett, M. G.

    2012-12-01

    Emerald ash borer (Agrilus planipennis Fairmaire; EAB), a non-native invasive beetle, has caused substantial damage to green (Fraxinus pennsylvanica Marsh.), white (Fraxinus americana L.), and black ash (Fraxinus nigra Marsh.), the major ash species of North America. In the absence of effective methods for controlling or eradicating the beetle, EAB continues to spread unimpeded across North America. Evidence indicates the mortality rate for EAB-infested trees near the epicenter of the infestation in southeast Michigan exceeds 99 percent for the major ash species. One possible climatic limitation on the spread of the infestation is suggested by recent work indicating that beetles cannot survive exposure to temperatures below -35.3 degrees Celsius. We considered whether this thermal constraint will limit the spread and distribution of EAB in North America. Historical climatic data for the United States and Canada were employed along with thermal models of the conditions beneath likely winter snowpack and beneath tree bark to predict the potential geographic distribution of the invasion. Results suggested the thermal mortality constraint will not lead to the protection of ash stands across most of North America. However, recent work indicates the majority of beetles cannot survive exposure to temperatures below -30 degrees Celsius. Along with our results, this suggests thermal constraints near the northern and western edges of the ranges of ash might limit EAB survival to some extent, thereby reducing the EAB population, the likelihood of EAB infestation, and subsequent ash mortality.

  13. Standards and Guidelines of the Reading Recovery [TM] Council of North America. Third Edition: Fall 1998.

    Science.gov (United States)

    Reading Recovery Council of North America, Columbus, OH.

    This booklet outlines the Reading Recovery Council of North America's (RRCNA) standards and guidelines for those who are responsible for the establishment and maintenance of effective Reading Recovery and/or "Descubriendo La Lectura" sites. The standards are deemed essential for assuring quality services to children and effective implementation of…

  14. North America's Native Peoples: A Social Justice and Trauma Counseling Approach

    Science.gov (United States)

    Turner, Sherri L.; Pope, Mark

    2009-01-01

    This article understands North America's indigenous peoples in the context of social justice. The authors discuss the role of legislation in shaping cultural contexts of indigenous people and influencing mental health issues in Native American communities. Trauma counseling with Native Americans is explored.

  15. Effects of Nitrogen Deposition on Greenhouse-Gas Fluxes for Forests and Grasslands of North America

    Science.gov (United States)

    Human activities have substantially elevated the atmospheric deposition of reactive nitrogen (N) onto terrestrial ecosystems of North America. Some of this N can stimulate carbon (C) storage in terrestrial ecosystems, but the fertilization effect of added N can be diminished by e...

  16. 78 FR 48909 - SGS North America, Inc. (formerly SGS U.S. Testing Company, Inc.)

    Science.gov (United States)

    2013-08-12

    ... Occupational Safety and Health Administration SGS North America, Inc. (formerly SGS U.S. Testing Company, Inc.) AGENCY: Occupational Safety and Health Administration (OSHA), Labor. ACTION: Notice. SUMMARY: This notice announces the Occupational Safety and Health Administration's final decision expanding the recognition...

  17. Insects of sunflower in the northern Great Plains of North America

    Science.gov (United States)

    The ancestors of cultivated sunflower, Helianthus annuus L., are native to North America and approximately 13 of the 51 species in the genus Helianthus are reported to occur in Canada. Sunflower was introduced to Spain in the early 1500s, gradually spread across the European continent, and was then ...

  18. History of the invasion of the anther smut pathogen on Silene latifolia in North America

    NARCIS (Netherlands)

    Fontaine, Michael C; Gladieux, Pierre; Hood, Michael E; Giraud, Tatiana

    2013-01-01

    Understanding the routes of pathogen introduction contributes greatly to efforts to protect against future disease emergence. Here, we investigated the history of the invasion in North America by the fungal pathogen Microbotryum lychnidis-dioicae, which causes the anther smut disease on the white ca

  19. 75 FR 57911 - Application to Export Electric Energy; EDF Trading North America, LLC

    Science.gov (United States)

    2010-09-23

    ... Application to Export Electric Energy; EDF Trading North America, LLC AGENCY: Office of Electricity Delivery... (EDF) has applied for authority to transmit electric energy from the United States to Mexico pursuant... application from EDF for authority to transmit electric energy from the United States to Mexico for five...

  20. 75 FR 26202 - Application To Export Electric Energy; EDF Trading North America, LLC

    Science.gov (United States)

    2010-05-11

    ... Application To Export Electric Energy; EDF Trading North America, LLC AGENCY: Office of Electricity Delivery... (EDF) has applied for authority to transmit electric energy from the United States to Canada pursuant... application from EDF for authority to transmit electric energy from the United States to Canada as a...

  1. Genetic distinctions between autoimmune hepatitis in Italy and North America

    Institute of Scientific and Technical Information of China (English)

    Paolo Muratori; Marco Lenzi; Francesco B. Bianchi; Albert J. Czaja; Luigi Muratori; Georgios Pappas; Silvana Maccariello; Fabio Cassani; Alessandro Granito; Rodolfo Ferrari; Vilma Mantovani

    2005-01-01

    AIM: Our goals were to analyze the known genetic predispositions for autoimmune hepatitis (AIH) in AIH Italian population and to compare them with North American counterparts.METHODS: Human leukocyte antigens (HLA) B8, C7, DR3,DR4, DR7, DR11, DR13, DQ2 and the B8-DR3-DQ2phenotype were determined by microlymphocytotoxicity and polymerase chain reaction in 74 Italian patients (57with type 1 and 17 with type 2 AIH) and 149 North American patients with type 1 AIH, and in adequate controls.RESULTS: B8-DR3-DQ2 occurred more frequently in Italian patients with type 1 AIH than in Italian controls (30% vs 7%, P<0.0001), but less frequently than in North American counterparts (30% vs48%, P = 0.02). DR4 occurred less frequently in Italian patients with type 1 AIH (23% vs43%,P= 0.01) and in controls (16% vs34%, P= 0.0003) than in North American counterparts. No differences were found in alleles' frequency between type 1 and type 2Italian AIH patients. DR11 had a frequency lower in type 1 Italian AIH patients than controls (17% vs35%, P= 0.01).CONCLUSION: HLA DR4 is not associated with AIH in Italy. The known HLA risk factors for ATH occur similarly in Italian patients with type 1 and type 2 AIH, and they are less frequent than in North American patients. B8-DR3-DQ2 is the predominant phenotype of type 1 AIH also in Italy, and HLA DR11 may be a regionally distinctive protective factor against type 1 AIH.

  2. First Detection of Bat White-Nose Syndrome in Western North America.

    Science.gov (United States)

    Lorch, Jeffrey M; Palmer, Jonathan M; Lindner, Daniel L; Ballmann, Anne E; George, Kyle G; Griffin, Kathryn; Knowles, Susan; Huckabee, John R; Haman, Katherine H; Anderson, Christopher D; Becker, Penny A; Buchanan, Joseph B; Foster, Jeffrey T; Blehert, David S

    2016-01-01

    White-nose syndrome (WNS) is an emerging fungal disease of bats caused by Pseudogymnoascus destructans. Since it was first detected near Albany, NY, in 2006, the fungus has spread across eastern North America, killing unprecedented numbers of hibernating bats. The devastating impacts of WNS on Nearctic bat species are attributed to the likely introduction of P. destructans from Eurasia to naive host populations in eastern North America. Since 2006, the disease has spread in a gradual wavelike pattern consistent with introduction of the pathogen at a single location. Here, we describe the first detection of P. destructans in western North America in a little brown bat (Myotis lucifugus) from near Seattle, WA, far from the previously recognized geographic distribution of the fungus. Whole-genome sequencing and phylogenetic analyses indicated that the isolate of P. destructans from Washington grouped with other isolates of a presumed clonal lineage from the eastern United States. Thus, the occurrence of P. destructans in Washington does not likely represent a novel introduction of the fungus from Eurasia, and the lack of intensive surveillance in the western United States makes it difficult to interpret whether the occurrence of P. destructans in the Pacific Northwest is disjunct from that in eastern North America. Although there is uncertainty surrounding the impacts of WNS in the Pacific Northwest, the presence of the pathogen in western North America could have major consequences for bat conservation. IMPORTANCE White-nose syndrome (WNS) represents one of the most consequential wildlife diseases of modern times. Since it was first documented in New York in 2006, the disease has killed millions of bats and threatens several formerly abundant species with extirpation or extinction. The spread of WNS in eastern North America has been relatively gradual, inducing optimism that disease mitigation strategies could be established in time to conserve bats susceptible

  3. Genotypic variation and mixtures of Lyme Borrelia in Ixodes ticks from North America and Europe.

    Directory of Open Access Journals (Sweden)

    Chris D Crowder

    Full Text Available BACKGROUND: Lyme disease, caused by various species of Borrelia, is transmitted by Ixodes ticks in North America and Europe. Studies have shown the genotype of Borrelia burgdorferi sensu stricto (s.s. or the species of B. burgdorferi sensu lato (s.l. affects the ability of the bacteria to cause local or disseminated infection in humans. METHODOLOGY/PRINCIPAL FINDINGS: We used a multilocus PCR electrospray mass spectrometry assay to determine the species and genotype Borrelia from ticks collected in New York, Connecticut, Indiana, Southern Germany, and California and characterized isolates from parts of the United States and Europe. These analyses identified 53 distinct genotypes of B. burgdorferi sensu stricto with higher resolution than ospC typing. Genotypes of other members of the B. burgdorferi sensu lato complex were also identified and genotyped including B. afzelii, B. garinii, B. lusitaniae, B. spielmanii, and B. valaisiana. While each site in North America had genotypes unique to that location, we found genotypes shared between individual regions and two genotypes found across the United States. Significant B. burgdorferi s.s. genotypic diversity was observed between North America and Europe: only 6.6% of US genotypes (3 of 45 were found in Europe and 27% of the European genotypes (3 of 11 were observed in the US. Interestingly, 39% of adult Ixodes scapularis ticks from North America were infected with more than one genotype of B. burgdorferi s.s. and 22.2% of Ixodes ricinus ticks from Germany were infected with more than one genotype of B. burgdorferi s.l. CONCLUSIONS/SIGNIFICANCE: The presence of multiple Borrelia genotypes in ticks increases the probability that a person will be infected with more than one genotype of B. burgdorferi, potentially increasing the risks of disseminated Lyme disease. Our study indicates that the genotypic diversity of Borrelia in ticks in both North America and Europe is higher then previously reported

  4. Historical atmospheric mercury emissions and depositions in North America compared to mercury accumulations in sedimentary records

    Science.gov (United States)

    Pirrone, Nicola; Allegrini, Ivo; Keeler, Gerald J.; Nriagu, Jerome O.; Rossmann, Ronald; Robbins, John A.

    Gold and silver production in North America (included United States, Canada and Mexico) released a large amount of mercury to the atmosphere until well into this century when mercury (Hg) amalgamation was replaced by cyanide concentration. Since then, emissions from industries have been the dominant anthropogenic sources of atmospheric Hg in North America as a whole. Past Hg emissions from gold and silver extractions in North America during the 1800s do not show a clear evidence of atmospheric deposition occurred at the coring sites considered in this study. Estimated atmospheric emissions of Hg in North America peaked in 1879 (at about 1708 t yr -1) and 1920 (at about 940 t yr -1), primarily due to Hg emissions from gold and silver mining. After the Great Economic Depression (1929) Hg emissions peaked again in the 1947 (274 t yr -1), in 1970 (325 t yr -1) and in 1989 (330 t yr -1) as result of increased Hg emissions from industrial sources, though improvements in the emissions control technology in United States and Canada have been substantial. Estimates of total atmospheric deposition fluxes of Hg to water and terrestrial receptors were in the range of 14.3-19.8 μg m -2 yr -1 in North America as a whole, and averaged 135 μg m -2 yr -1 (global background + local emissions) in the Great Lakes. These values were in good agreement with recent estimates reported in literature. The comparison of atmospheric Hg deposition fluxes with Hg accumulation rates in sediment cores suggests that atmospheric deposition was the major source of Hg entering the lakes system at coring sites, however, important contributions to Lake Ontario sediment cores sites from 1940 to 1970 were likely originated from local point sources (i.e. direct discharges).

  5. A New Fishfly Species (Megaloptera: Corydalidae: Neohermes Banks) Discovered from North America by a Systematic Revision, with Phylogenetic and Biogeographic Implications.

    Science.gov (United States)

    Liu, Xingyue; Winterton, Shaun L

    2016-01-01

    The taxonomy of Megaloptera from the Nearctic region is fairly well known and their faunal diversity has been largely surveyed, even in relatively remote regions. However, the evolutionary history of Nearctic Megaloptera is still poorly known with phylogenetic and biogeographic studies lacking. In this paper, we report a new fishfly species of the endemic North American genus Neohermes Banks, 1908, increasing the total number known of species to six. This new species (Neohermes inexpectatus sp. nov.) is currently known to occur only in California (USA) and is apparently confined to the Northern Coastal Range. The new species resembles the three Neohermes species from eastern North America based on the relatively small body size and the presence of female gonostyli 9. However, our phylogenetic analysis using adult morphological data recovered the new species as the sister species to the remaining Neohermes, which includes two species from western North America and three from eastern North America. According to the present interspecific phylogeny of Neohermes, with reconstructed ancestral areas, the initial divergence within the genus was found to take place in western North America, with a subsequent eastward dispersal. This likely lead to the modern distribution of Neohermes in eastern North America with the closure of the Mid-Continental Seaway, which separated western and eastern North America in the Mid-Late Cretaceous (100-80 MYA) and finally disappeared at the end of the Cretaceous (70 MYA). The uplift of the Cordilleran System probably accounted for the divergence between the eastern and two western Neohermes species. PMID:26886194

  6. A New Fishfly Species (Megaloptera: Corydalidae: Neohermes Banks Discovered from North America by a Systematic Revision, with Phylogenetic and Biogeographic Implications.

    Directory of Open Access Journals (Sweden)

    Xingyue Liu

    Full Text Available The taxonomy of Megaloptera from the Nearctic region is fairly well known and their faunal diversity has been largely surveyed, even in relatively remote regions. However, the evolutionary history of Nearctic Megaloptera is still poorly known with phylogenetic and biogeographic studies lacking. In this paper, we report a new fishfly species of the endemic North American genus Neohermes Banks, 1908, increasing the total number known of species to six. This new species (Neohermes inexpectatus sp. nov. is currently known to occur only in California (USA and is apparently confined to the Northern Coastal Range. The new species resembles the three Neohermes species from eastern North America based on the relatively small body size and the presence of female gonostyli 9. However, our phylogenetic analysis using adult morphological data recovered the new species as the sister species to the remaining Neohermes, which includes two species from western North America and three from eastern North America. According to the present interspecific phylogeny of Neohermes, with reconstructed ancestral areas, the initial divergence within the genus was found to take place in western North America, with a subsequent eastward dispersal. This likely lead to the modern distribution of Neohermes in eastern North America with the closure of the Mid-Continental Seaway, which separated western and eastern North America in the Mid-Late Cretaceous (100-80 MYA and finally disappeared at the end of the Cretaceous (70 MYA. The uplift of the Cordilleran System probably accounted for the divergence between the eastern and two western Neohermes species.

  7. The role of emergency medicine physicians in trauma care in North America: evolution of a specialty

    Directory of Open Access Journals (Sweden)

    Grossman Michael D

    2009-08-01

    Full Text Available Abstract The role of Emergency Medicine Physicians (EMP in the care of trauma patients in North America has evolved since the advent of the specialty in the late 1980's. The evolution of this role in the context of the overall demands of the specialty and accreditation requirements of North American trauma centers will be discussed. Limited available data published in the literature examining the role of EMP's in trauma care will be reviewed with respect to its implications for an expanded role for EMPs in trauma care. Two training models currently in the early stages of development have been proposed to address needs for increased manpower in trauma and the critical care of trauma patients. The available information regarding these models will be reviewed along with the implications for improving the care of trauma patients in both Europe and North America.

  8. Test of the invasive pathogen hypothesis of bumble bee decline in North America.

    Science.gov (United States)

    Cameron, Sydney A; Lim, Haw Chuan; Lozier, Jeffrey D; Duennes, Michelle A; Thorp, Robbin

    2016-04-19

    Emergent fungal diseases are critical factors in global biodiversity declines. The fungal pathogenNosema bombiwas recently found to be widespread in declining species of North American bumble bees (Bombus), with circumstantial evidence suggesting an exotic introduction from Europe. This interpretation has been hampered by a lack of knowledge of global genetic variation, geographic origin, and changing prevalence patterns ofN. bombiin declining North American populations. Thus, the temporal and spatial emergence ofN. bombiand its potential role in bumble bee decline remain speculative. We analyzeNosemaprevalence and genetic variation in the United States and Europe from 1980, before an alleged introduction in the early 1990s, to 2011, extractingNosemaDNA fromBombusnatural history collection specimens from across this time period.Nosema bombiprevalence increased significantly from low detectable frequency in the 1980s to significantly higher frequency in the mid- to late-1990s, corresponding to a period of reported massive infectious outbreak ofN. bombiin commercial bumble bee rearing stocks in North America. Despite the increased frequency, we find no conclusive evidence of an exoticN. bombiorigin based on genetic analysis of globalNosemapopulations; the widespreadNosemastrain found currently in declining United States bumble bees was present in the United States before commercial colony trade. Notably, the USN. bombiis not detectably different from that found predominantly throughout Western Europe, with both regions characterized by low genetic diversity compared with high levels of diversity found in Asia, where commercial bee breeding activities are low or nonexistent. PMID:27044096

  9. Present-Day 3D Velocity Field of Eastern North America Based on Continuous GPS Observations

    Science.gov (United States)

    Goudarzi, Mohammad Ali; Cocard, Marc; Santerre, Rock

    2016-07-01

    The Saint Lawrence River valley in eastern Canada was studied using observations of continuously operating GPS (CGPS) stations. The area is one of the most seismically active regions in eastern North America characterized by many earthquakes, which is also subject to an ongoing glacial isostatic adjustment. We present the current three-dimensional velocity field of eastern North America obtained from more than 14 years (9 years on average) of data at 112 CGPS stations. Bernese GNSS and GITSA software were used for CGPS data processing and position time series analysis, respectively. The results show the counterclockwise rotation of the North American plate in the No-Net-Rotation model with the average of 16.8 ± 0.7 mm/year constrained to ITRF 2008. We also present an ongoing uplift model for the study region based on the present-day CGPS observations. The model shows uplift all over eastern Canada with the maximum rate of 13.7 ± 1.2 mm/year and subsidence to the south mainly over northern USA with a typical rate of -1 to -2 mm/year and the minimum value of -2.7 ± 1.4 mm/year. We compared our model with the rate of radial displacements from the ICE-5G model. Both models agree within 0.02 mm/year at the best stations; however, our model shows a systematic spatial tilt compared to ICE-5G. The misfits between two models amount to the maximum relative subsidence of -6.1 ± 1.1 mm/year to the east and maximum relative uplift of 5.9 ± 2.7 mm/year to the west. The intraplate horizontal velocities are radially outward from the centers of maximum uplift and are inward to the centers of maximum subsidence with the typical velocity of 1-1.6 ± 0.4 mm/year that is in agreement with the ICE-5G model to the first order.

  10. Present-Day 3D Velocity Field of Eastern North America Based on Continuous GPS Observations

    Science.gov (United States)

    Goudarzi, Mohammad Ali; Cocard, Marc; Santerre, Rock

    2016-03-01

    The Saint Lawrence River valley in eastern Canada was studied using observations of continuously operating GPS (CGPS) stations. The area is one of the most seismically active regions in eastern North America characterized by many earthquakes, which is also subject to an ongoing glacial isostatic adjustment. We present the current three-dimensional velocity field of eastern North America obtained from more than 14 years (9 years on average) of data at 112 CGPS stations. Bernese GNSS and GITSA software were used for CGPS data processing and position time series analysis, respectively. The results show the counterclockwise rotation of the North American plate in the No-Net-Rotation model with the average of 16.8 ± 0.7 mm/year constrained to ITRF 2008. We also present an ongoing uplift model for the study region based on the present-day CGPS observations. The model shows uplift all over eastern Canada with the maximum rate of 13.7 ± 1.2 mm/year and subsidence to the south mainly over northern USA with a typical rate of -1 to -2 mm/year and the minimum value of -2.7 ± 1.4 mm/year. We compared our model with the rate of radial displacements from the ICE-5G model. Both models agree within 0.02 mm/year at the best stations; however, our model shows a systematic spatial tilt compared to ICE-5G. The misfits between two models amount to the maximum relative subsidence of -6.1 ± 1.1 mm/year to the east and maximum relative uplift of 5.9 ± 2.7 mm/year to the west. The intraplate horizontal velocities are radially outward from the centers of maximum uplift and are inward to the centers of maximum subsidence with the typical velocity of 1-1.6 ± 0.4 mm/year that is in agreement with the ICE-5G model to the first order.

  11. The Role of Soil Water and Land Feedbacks in Decadal Drought in Western North America

    Science.gov (United States)

    Langford, S.; Chikamoto, Y.; Noone, D. C.

    2013-12-01

    Western North America is susceptible to severe impacts of megadroughts, as evidenced by tree-core or lake sediment records. Future predictions suggest that this region will become more arid, with further consequences for water resources. Understanding the mechanisms of drought variability and persistence in western North America is critical for the eventual development of effective forecasting methods. The ocean is expected to be the main source of decadal memory in the system as the atmosphere varies on a much shorter timescale. The ocean's role in driving the low-frequency variability of the system is potentially predictable. However, low-frequency precipitation anomalies in western North America can occur in the absence of ocean feedbacks. Sea surface temperature anomalies in the north Pacific Ocean only account for around 20 per cent of the low-frequency winter precipitation in California in the CMIP5 historical runs. This is not sufficient to use the skill of global coupled models in predicting ocean conditions ahead of time to successfully forecast the possibility of long-term drought in western North America. Megadroughts therefore may be generated by unpredictable atmospheric noise, or persisted by other sources of low-frequency variability such as land processes and feedbacks. Snowpack in western North America is a crucial water resource for the surrounding communities, storing the winter precipitation for use later in the year. Likewise, soil moisture integrates the precipitation signal; the time scale depends on the depth and characteristics of the soil. Water storage and related variables are more predictable on longer timescales than precipitation, as measured by anomaly correlation for hindcasts compared to a 'perfect model' control run with CESM1.0.3. The importance of antecedent land conditions in persisting megadroughts in western North America is explored with ensemble simulations of CESM1.0.3, where the atmosphere is perturbed at the initiation

  12. Patterns of admixture and population structure in native populations of Northwest North America.

    Directory of Open Access Journals (Sweden)

    Paul Verdu

    2014-08-01

    Full Text Available The initial contact of European populations with indigenous populations of the Americas produced diverse admixture processes across North, Central, and South America. Recent studies have examined the genetic structure of indigenous populations of Latin America and the Caribbean and their admixed descendants, reporting on the genomic impact of the history of admixture with colonizing populations of European and African ancestry. However, relatively little genomic research has been conducted on admixture in indigenous North American populations. In this study, we analyze genomic data at 475,109 single-nucleotide polymorphisms sampled in indigenous peoples of the Pacific Northwest in British Columbia and Southeast Alaska, populations with a well-documented history of contact with European and Asian traders, fishermen, and contract laborers. We find that the indigenous populations of the Pacific Northwest have higher gene diversity than Latin American indigenous populations. Among the Pacific Northwest populations, interior groups provide more evidence for East Asian admixture, whereas coastal groups have higher levels of European admixture. In contrast with many Latin American indigenous populations, the variance of admixture is high in each of the Pacific Northwest indigenous populations, as expected for recent and ongoing admixture processes. The results reveal some similarities but notable differences between admixture patterns in the Pacific Northwest and those in Latin America, contributing to a more detailed understanding of the genomic consequences of European colonization events throughout the Americas.

  13. 1987 wet deposition temporal and spatial patterns in North America

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.C.; Olsen, A.R.

    1990-03-01

    The focus of this report is on North American wet deposition temporal patterns from 1979 to 1987 and spatial patterns for 1987. The report investigates the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Data are from the Acid Deposition System (ADS) for the statistical reporting of North American deposition data which includes the National Atmospheric Deposition Program/National Trends Network (NADP/NTN), the MAP3S precipitation chemistry network, the Utility Acid Precipitation Study Program (UAPSP), the Canadian Precipitation Monitoring Network (CAPMoN), and the daily and 4-weekly Acidic Precipitation in Ontario Study (APIOS-D and APIOS-C). Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1987 annual, winter, and summer periods. The temporal pattern analyses use a subset of 39 sites over a 9-year (1979--1987) period and an expanded subset of 140 sites with greater spatial coverage over a 6-year (1982--1987) period. 68 refs., 15 figs., 15 tabs.

  14. The Megophthalmidia (Diptera, Mycetophilidae) of North America including eight new species.

    Science.gov (United States)

    Kerr, Peter H

    2014-01-01

    Megophthalmidia Dziedzicki is a small leiine genus (Mycetophilidae) with seven species described from the Neotropics and ten species from the Palearctic region. Two species of Megophthalmidia have been reported for North America. Recent collecting of Mycetophilidae in California and Arizona, however, shows current North American diversity of Megophthalmidia is at least on par to other regions of the world. Eight new species of Megophthalmidia are described here, increasing the number of Nearctic Megophthalmidia species to nine. Included is a particularly atypical member of the genus, M. saskia sp. n., which expands the genus concept of Megophthalmidia. Of the two species previously recorded for North America, only one actually belongs in the genus. Megophthalmidia occidentalis Johannsen, is fully described and illustrated. The other named species, M. marceda (Sherman) is illustrated and transferred to the genus Ectrepesthoneura Enderlein. A lectotype is designated for this species. A key to the species of Megophthalmidia of North America is provided. The biology of these flies is not yet known. Three of the new Megophthalmidia species - M. lenimenta, M. misericordia, and M. radiata - are only known to occur within small protected areas within the California State Park and UC Natural Reserve systems. PMID:24693214

  15. A mid to late Holocene cryptotephra framework from eastern North America

    Science.gov (United States)

    Mackay, Helen; Hughes, Paul D. M.; Jensen, Britta J. L.; Langdon, Pete G.; Pyne-O'Donnell, Sean D. F.; Plunkett, Gill; Froese, Duane G.; Coulter, Sarah; Gardner, James E.

    2016-01-01

    Holocene cryptotephras of Alaskan and Pacific Northwestern origin have recently been detected ca. 7000 km away on the east coast of North America. This study extends the emerging North American tephrochronological framework by geochemically characterising seventeen cryptotephra layers from four newly explored peatlands. All detected tephras were deposited during the late Holocene, with no horizons present in the peat between ca. 3000-5000 years ago. The prevalence of the Alaskan White River Ash eastern lobe (AD 847 ± 1) is confirmed across the eastern seaboard from Newfoundland to Maine and a regional depositional pattern from Mount St Helens Set W (AD 1479-1482) is presented. The first occurrences of four additional cryptotephras in eastern North America are described, three of which may originate from source regions in Mexico, Kamchatka (Russia) and Hokkaido (Japan). The possibility of such tephras reaching eastern North America presents the opportunity to link palaeo-archives from the tropics and eastern Asia with those from the western Atlantic seaboard, aiding inter-regional comparisons of proxy-climatic records.

  16. The Megophthalmidia (Diptera, Mycetophilidae of North America including eight new species

    Directory of Open Access Journals (Sweden)

    Peter Kerr

    2014-03-01

    Full Text Available Megophthalmidia Dziedzicki is a small leiine genus (Mycetophilidae with seven species described from the Neotropics and ten species from the Palearctic region. Two species of Megophthalmidia have been reported for North America. Recent collecting of Mycetophilidae in California and Arizona, however, shows current North American diversity of Megophthalmidia is at least on par to other regions of the world. Eight new species of Megophthalmidia are described here, increasing the number of Nearctic Megophthalmidia species to nine. Included is a particularly atypical member of the genus, M. saskia sp. n., which expands the genus concept of Megophthalmidia. Of the two species previously recorded for North America, only one actually belongs in the genus. Megophthalmidia occidentalis Johannsen, is fully described and illustrated. The other named species, M. marceda (Sherman is illustrated and transferred to the genus Ectrepesthoneura Enderlein. A lectotype is designated for this species. A key to the species of Megophthalmidia of North America is provided. The biology of these flies is not yet known. Three of the new Megophthalmidia species – M. lenimenta, M. misericordia, and M. radiata – are only known to occur within small protected areas within the California State Park and UC Natural Reserve systems.

  17. Distribution of Xiphinema americanum and Related Species in North America.

    Science.gov (United States)

    Robbins, R T

    1993-09-01

    All species of the Xiphinema americanum-group and their synonyms are listed. The North American species reported are listed by state or province. Among these species, X. rivesi has the most widely reported distribution. Six species (X. diffusum, X. floridae, X. laevistriatum, X. luci, X. shell, and X. tarjanense) have been reported from only Florida. The reports of X. pachtaicum, X. sheri, and X. luci did not include morphometrics and need to be confirmed; X. brevicolle from California was identified before Lamberti and Bleve-Zacheo described 15 new species in 1979 and similarly needs to be confirmed. Because of the proliferation of species in this group, reports of X. americanum (sensu stricto) before 1979 are questionable. Extraction techniques for longidorids are discussed.

  18. Book review: Ducks, geese, and swans of North America

    Science.gov (United States)

    Wilson, Robert E.

    2016-01-01

    As pointed out in the book’s introduction by Richard McCabe, very few books deserve being called a classic. First published in 1942, the various editions of Ducks, Geese, and Swans of North America—authored by Francis K. Kortright (1942), Frank C. Bellrose (1976, 1981), and this new edition by Guy Baldassarre (2014)—are deservedly placed in that category among the waterfowl literature. This book has been a valuable resource for the scientific community and waterfowl enthusiasts, and I was excited to learn that a new version has been published. As expected, this new edition did not disappoint and is a remarkable volume in terms of incorporating current research into each species account in a way that does not overwhelm either professional or amateur readers.

  19. Population trends of grassland birds in North America are linked to the prevalence of an agricultural epizootic in Europe.

    Science.gov (United States)

    Nocera, Joseph J; Koslowsky, Hannah M

    2011-03-22

    Globalization of trade has dramatic socioeconomic effects, and, intuitively, significant ecological effects should follow. However, few quantitative examples exist of the interrelationship of globalization, socioeconomics, and ecological patterns. We present a striking illustration of a cascade in which bovine spongiform encephalopathy (BSE; "mad cow disease") outbreaks in Europe exerted pressure on global beef markets, subsequently affecting North American hayfields and grassland bird populations. We examined competing models, which linked the prevalence of BSE in five focal countries, volume of beef exports to those countries from North America, and the amount of hayfield harvested and the abundance of grassland birds in North America. We found that (i) imports from North America increased 1 y after BSE outbreaks; (ii) probably because fewer cattle remained, the hay harvest in North America was reduced 2 y after the outbreak; (iii) the reduced hay harvest yielded a positive response in grassland bird populations 3 y after the outbreak. PMID:21383197

  20. Powering Up: Assessing the growing municipal energy resilience building efforts in North America

    Science.gov (United States)

    Schimmelfing, Kara

    Energy related shortages and price volatilities can impact all levels of society. With coming fossil fuel depletion related to peak oil, it is expected these shortages and volatilities will increase in frequency, duration, and intensity. Resilience building is a strategy to minimize the effects of these events by modifying systems so they are less impacted and/or recover more quickly from disruptive events. Resilience building is being used, particularly at the municipal scale, to prepare for these coming energy related changes. These municipal efforts have only been in existence for five to ten years, and full implementation is still in progress. Little evaluation has been done of these municipal efforts to date, particularly in North America. Despite this, it is important to begin to assess the effectiveness of these efforts now. As a result, future efforts can be redirected to address weak areas and that lessons learned by vanguard communities can be applied in other communities attempting to build energy resilience in the future. This thesis involved the creation of a hybrid framework to evaluate municipal energy resilience building efforts. The framework drew primarily from planning process and factors identified as important to build resilience in social-ecological systems. It consisted of the following categories to group resilience building efforts: Economy, Resource Systems & Infrastructure, Public Awareness, Social Services, Transportation, Built Environment, and Natural Environment. Within these categories the following process steps should be observed: Context, Goals, Needs, Processes, and Outcomes. This framework was then tested through application to four case-study communities (Bloomington, IN, Hamilton, ON, Oakland, CA, Victoria, BC) currently pursuing energy resilience building efforts in North America. This qualitative research involved document analysis primarily of municipal documents related to energy planning efforts. Supplementary interviews

  1. Managing Current Complexity: Critical Energy Infrastructure Failures in North America

    Directory of Open Access Journals (Sweden)

    Colin MacDonald

    2012-04-01

    Full Text Available

    This paper applies the competing theories of High Reliability Organizations (HRO and Normal Accidents Theory (NAT, two competing views of risk management in highly-complex and tightly-coupled systems, in analyzing the 1998 Ice Storm and the 2003 Blackout to examine vulnerabilities in North America’s critical energy infrastructure (CEI. Inferences are then made by highlighting the similarities and differences in the two cases, which are then used to draw lessons for public managers regarding the protection of CEIs.

     

    As CEIs are highly-complex and tightly-coupled systems, failures stemming from complex and uncertain risks are inevitable. There is an increasingly low tolerance for failure in energy infrastructure because society’s critical infrastructures have become increasingly interdependent. Public managers must regulate CEIs in order to ensure an emphasis is placed on safety and security while also finding ways to reduce unnecessary complexities. It is through the adoption of such measures that public managers will aid in minimizing the cascading effects of inevitable failures.

     

  2. 1988 Wet deposition temporal and spatial patterns in North America

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.C.; Olsen, A.R.; Bittner, E.A.

    1992-03-01

    The focus of this report is on North American wet deposition temporal patterns from 1979 to 1988 and spatial patterns for 1988. It is the third in a series of reports that investigate the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1988 annual, winter, and summer periods. Temporal pattern analyses use a subset of 35 sites over a 10-year (1979--1988) period and an expanded subset of 137 sites, with greater spatial coverage, over a 7-year (1982--1988) period. The 10-year period represents the longest period with wet deposition monitoring data available that has a sufficient number of sites with data of known quality to allow a descriptive summary of annual temporal patterns. Sen's median trend estimate and Kendall's seasonal tau (KST) test are calculated for each ion species concentration and deposition at each site in both subsets.

  3. 1988 Wet deposition temporal and spatial patterns in North America

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.C.; Olsen, A.R.; Bittner, E.A.

    1992-03-01

    The focus of this report is on North American wet deposition temporal patterns from 1979 to 1988 and spatial patterns for 1988. It is the third in a series of reports that investigate the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1988 annual, winter, and summer periods. Temporal pattern analyses use a subset of 35 sites over a 10-year (1979--1988) period and an expanded subset of 137 sites, with greater spatial coverage, over a 7-year (1982--1988) period. The 10-year period represents the longest period with wet deposition monitoring data available that has a sufficient number of sites with data of known quality to allow a descriptive summary of annual temporal patterns. Sen`s median trend estimate and Kendall`s seasonal tau (KST) test are calculated for each ion species concentration and deposition at each site in both subsets.

  4. The industrial applications of shape memory alloys in North America

    International Nuclear Information System (INIS)

    Literature in the recent past on shape memory effect alloys dwelt principally on the physical metallurgy, crystallography and kinetics of the shape memory phenomenon. By contrast, we now have books and conference proceedings devoted to the engineering aspects of SMAs, their technology and application. The dominant role SMAs now play in the field of medical and orthodontic devices is well documented and will be reviewed by others in this conference. In this paper we will discuss the commercial applications for shape memory alloy devices in the North American market; applications which are in many cases also produced in European countries and Japan. The early success of shape memory alloy couplings for joining tubing and pipe in the late 1960's was not followed by other large volume applications until the advent of shape memory eyeglass frames, brassiere underwires and cellular phone antennas. Many other applications have now evolved into mature markets and these will be reviewed. In addition to the many commercial applications cited, there are a number of other fields in which shape memory alloys are destined to play a major role; these include smart materials and adaptive structures, MEMS devices, infrastructure systems and electrical power generation and distribution. These applications are being developed with private and government funding and will also be briefly discussed. (orig.)

  5. Selection of motors for end customer use and installation in North America

    Energy Technology Data Exchange (ETDEWEB)

    Malinowski, J. [Baldor Electric Co., Fort Smith, AR (United States)

    2005-07-01

    This paper will discuss the challenge of equipment builders wishing to export machinery to the North American market where NEMA standards are preferred. Although IEC motors and reducers are available in North America, end users prefer motors and gear reducers with NEMA characteristics and efficiency levels. Replacement IEC motors and gearmotors are available in North America, however they are not as readily available from distributors as NEMA motors. End users also favor separate C-face gear reducers rather than integral gearmotors. Use of readily available NEMA motors reduces plant downtime and cost when a motor fails. There is also a perception that NEMA motors are more robust and provide more temporary overload capability than IEC motors. NEMA premium registered efficiency levels tested using IEEE 112 and CSA 390 test methods are also favored by North American end users. Because of differences in test methods, IEEE and CSA efficiencies cannot be compared with IEC efficiencies due to the differences in test methods. The energy policy act defines the test methods and minimum efficiencies for motors sold in the United States. Motors with metric dimensions 1 - 200 HP must meet EPAct requirements. There is a market for NEMA motors outside of the United States for those manufacturers building equipment for use in the North American market. (orig.)

  6. The Mesozoic rift basins of eastern North America: Potential reservoir or Explorationist's folly

    Energy Technology Data Exchange (ETDEWEB)

    Pyron, A.

    1991-08-01

    Mesozoic rift basins are found on the East Coast of North America from Georgia to Nova Scotia. The basins formed as a result of extensional activity associated with the breakup of Pangaea. The internal geometry of the basins includes a depositional sequence ranging from coarse fanglomerates to fine-grained siltstones and argillites. Since these Mesozoic rift basins were first studied, they have not been considered to be likely spots for hydrocarbon accumulations. Recently, geologists have reconsidered these Mesozoic basins and have developed a more synergistic approach that suggests that many of these rift basins might be suitable targets for exploration. By analogy, these Mesozoic basins are correlative to similar basins in northwestern Africa, where significant reserved of oil and natural gas have been developed. The similarity between the productive basins in northwestern Africa and the Mesozoic basins of North America and their proximity to major markets provides sufficient rationale to further investigate these basins.

  7. Millennial-scale variability during the last glacial in vegetation records from North America

    Science.gov (United States)

    Jiménez-Moreno, Gonzalo; Anderson, R. Scott; Desprat, S.; Grigg, L.D.; Grimm, E.C.; Heusser, L.E.; Jacobs, Brian F.; Lopez-Martinez, C.; Whitlock, C.L.; Willard, D.A.

    2010-01-01

    High-resolution pollen records from North America show that terrestrial environments were affected by Dansgaard-Oeschger (D-O) and Heinrich climate variability during the last glacial. In the western, more mountainous regions, these climate changes are generally observed in the pollen records as altitudinal movements of climate-sensitive plant species, whereas in the southeast, they are recorded as latitudinal shifts in vegetation. Heinrich (HS) and Greenland (GS) stadials are generally correlated with cold and dry climate and Greenland interstadials (GI) with warm-wet phases. The pollen records from North America confirm that vegetation responds rapidly to millennial-scale climate variability, although the difficulties in establishing independent age models for the pollen records make determination of the absolute phasing of the records to surface temperatures in Greenland somewhat uncertain. ?? 2009 Elsevier Ltd.

  8. Extraterrestrial Markers Found at Clovis Sites Across North America

    Science.gov (United States)

    West, A.; Firestone, R. B.; Kennett, J. P.; Becker, L.

    2007-05-01

    We present evidence for an extraterrestrial (ET) impact event with Earth at about 12.9 ka, which, we hypothesize, caused abrupt environmental changes that contributed to Younger Dryas (YD) cooling, major ecological reorganization, broad-scale extinctions, and the rapid human behavioral shifts evident at the end of the Clovis Period. Terminal Clovis-age sites in North American are marked by a thin, discrete layer, the YD boundary layer (YDB) with varying peak abundances of an array or ET markers, including magnetic grains, microspherules, carbon spherules, soot, fullerenes with ET helium, and iridium. We will present data from a number of well- known Clovis sites and other locations in support of the YD impact event. Gainey, north of Detroit, Michigan, is a PaleoAmerican campsite that was located a few tens of kilometers from the southern margin of the Laurentide Ice Sheet at 12.9 ka. Gainey gave its name to the distinctive fluted point style found there, and Gainey sediments contained some of the highest abundances of YDB markers found, suggesting that the YD impact was centered nearby. Murray Springs, near Sierra Vista, Arizona is one of the best known Clovis mammoth kill-sites. A distinctive carbonaceous layer, called a "black mat" and thought to be of algal origin, drapes conformably over the mammoth bones (Haynes and Huckell, 2007). A thin layer (about 2 mm), the YDB, containing Younger Dryas impact event markers, lies at the base of the black mat and immediately overlies the mammoth bones and Clovis artifacts. Blackwater Draw, New Mexico is southwest of the town of Clovis, which gave its name to the type of projectile points first found there. It was a PaleoAmerican hunting site on the bank of a spring-fed waterhole, and the black mat drapes over bones of butchered mammoths and Clovis artifacts. Topper, located on a high bank of the Savannah River near Allendale, South Carolina, was a Clovis-age flint quarry containing thousands of artifacts. YDB markers occur

  9. A Tragedy of Democracy: Japanese Confinement in North America

    Directory of Open Access Journals (Sweden)

    Greg Robinson

    2010-03-01

    Full Text Available

    The confinement of some 120,000 Japanese Americans during World War II, often called the Japanese American internment, has been described as the worst official civil rights violation of modern U. S. history. Greg Robinson not only offers a bold new understanding of these events but also studies them within a larger time frame and from a transnational perspective. Drawing on newly discovered material, Robinson provides a backstory of confinement that reveals for the first time the extent of the American government's surveillance of Japanese communities in the years leading up to war and the construction of what officials termed "concentration camps" for enemy aliens. He also considers the aftermath of confinement, including the place of Japanese Americans in postwar civil rights struggles, the long movement by former camp inmates for redress, and the continuing role of the camps as touchstones for nationwide commemoration and debate. Most remarkably, A Tragedy of Democracy is the first book to analyze official policy toward West Coast Japanese Americans within a North American context. Robinson studies confinement on the mainland alongside events in wartime Hawaii, where fears of Japanese Americans justified Army dictatorship, suspension of the Constitution, and the imposition of military tribunals. He similarly reads the treatment of Japanese Americans against Canada's confinement of 22,000 citizens and residents of Japanese ancestry from British Columbia. A Tragedy of Democracy recounts the expulsion of almost 5,000 Japanese from Mexico's Pacific Coast and the poignant story of the Japanese Latin Americans who were kidnapped from their homes and interned in the United States. Approaching Japanese confinement as a continental and international phenomenon, Robinson offers a truly kaleidoscopic understanding of its genesis and outcomes.

  10. A Tragedy of Democracy: Japanese Confinement in North America

    Directory of Open Access Journals (Sweden)

    Greg Robinson

    2010-03-01

    Full Text Available The confinement of some 120,000 Japanese Americans during World War II, often called the Japanese American internment, has been described as the worst official civil rights violation of modern U. S. history. Greg Robinson not only offers a bold new understanding of these events but also studies them within a larger time frame and from a transnational perspective. Drawing on newly discovered material, Robinson provides a backstory of confinement that reveals for the first time the extent of the American government's surveillance of Japanese communities in the years leading up to war and the construction of what officials termed "concentration camps" for enemy aliens. He also considers the aftermath of confinement, including the place of Japanese Americans in postwar civil rights struggles, the long movement by former camp inmates for redress, and the continuing role of the camps as touchstones for nationwide commemoration and debate. Most remarkably, A Tragedy of Democracy is the first book to analyze official policy toward West Coast Japanese Americans within a North American context. Robinson studies confinement on the mainland alongside events in wartime Hawaii, where fears of Japanese Americans justified Army dictatorship, suspension of the Constitution, and the imposition of military tribunals. He similarly reads the treatment of Japanese Americans against Canada's confinement of 22,000 citizens and residents of Japanese ancestry from British Columbia. A Tragedy of Democracy recounts the expulsion of almost 5,000 Japanese from Mexico's Pacific Coast and the poignant story of the Japanese Latin Americans who were kidnapped from their homes and interned in the United States. Approaching Japanese confinement as a continental and international phenomenon, Robinson offers a truly kaleidoscopic understanding of its genesis and outcomes.

  11. Towards a high resolution inventory of anthropogenic deformation in North America using InSAR

    Science.gov (United States)

    Pritchard, M. E.; Lohman, R. B.; Taylor, H.; Semple, A.; Valentino, B.

    2015-12-01

    Anthropogenic surface deformation is important to measure for several reasons -- 1) it could be a hazard to infrastructure; 2) it could contaminate precise measurements of other types of deformation (e.g., magmatic or tectonic); and 3) the deformation can provide otherwise inaccessible information about the subsurface as we measure the Earth's response to known pumping, surface change, or mining activity. While there are studies at individual sites in North America that demonstrate these three types of studies, we lack a continental synoptic view of anthropogenic deformation and its significance. To fill this gap, we use satellite Interferometric Synthetic Aperture Radar (InSAR) data to image ground deformation across the continent with a spatial resolution of 1 km/pixel or better using results from the literature as well as new analysis of more than 5000 interferograms from the ERS, Envisat, and ALOS satellites, which collectively span 1992-2011. Our compilation is not complete in terms of spatially or temporal coverage nor is it uniform in quality over the region -- certainly we have missed some areas of deformation. Most of the data analyzed is in the western US, but ALOS observations east of the Rocky Mountains are of good quality even in vegetated and snowy areas and we document mining subsidence greater than several cm per year in NY, PA, and WV. We catalog more than 200 anthropogenic deformation signals, including about 45 that are not previously reported. The majority of these deformation sources can be attributed to groundwater extraction (66%), 8% to geothermal activity, 13% to hydrocarbon extraction, 11% to mining activity, and 2% to other sources such as lake loading. In a few areas, the source of deformation is not yet determined. As expected, most deformation is time dependent and so continuous monitoring is needed. In some areas, comparisonbetween pumping records and surface deformation reveals some suprises. For example, at the East Mesa Geothermal

  12. Genome-wide patterns of latitudinal differentiation among populations of Drosophila melanogaster from North America

    OpenAIRE

    Fabian, Daniel K; Kapun, Martin; Nolte, Viola; Kofler, Robert; Schmidt, Paul S; Schlötterer, Christian; Flatt, Thomas

    2012-01-01

    Abstract Understanding the genetic underpinnings of adaptive change is a fundamental but largely unresolved problem in evolutionary biology. Drosophila melanogaster, an ancestrally tropical insect that has spread to temperate regions and become cosmopolitan, offers a powerful opportunity for identifying the molecular polymorphisms underlying clinal adaptation. Here, we use genome-wide next-generation sequencing of DNA pools ('pool-seq') from three populations collected along the North America...

  13. Feminist Music Therapists in North America: Their Lives and Their Practices

    OpenAIRE

    Sandra L. Curtis

    2015-01-01

    This survey study investigated the lives and practices of those in North America who self-identify as feminist music therapists. Earlier reports from this survey studied: 1) the experiences of music therapists, with a comparison of men, women, and their 1990 counterparts (Curtis, 2013d); 2) the experiences of music therapists who self-identify as community music therapists (Curtis, 2015); and 3) the experiences of music therapists in Canada as they compare with their U.S. counterparts (Curtis...

  14. Associations of desire for change in sexual life amongst female medical students in North America

    OpenAIRE

    Shindel, AW; Breyer, BN; Smith, JF

    2012-01-01

    We analyzed associations of dissatisfaction with sexual life and desire for change in female medical students. Students enrolled in medical schools in North America between February and July 2008 were invited to participate in an internet-based survey of sexual function. The principle outcome measure was a single item question on sexual life satisfaction and desire for change. Women who reported dissatisfaction and desire for change were classified as 'sexually bothered'. The survey also asse...

  15. Petitioning process for irradiated foods and animal feeds in North America

    International Nuclear Information System (INIS)

    The lack of sufficient regulatory approvals continues to delay the commercial application of food irradiation in several countries. Often, the regulatory approval process itself appears too challenging and approvals are not even requested. The objective of this paper is to review petition requirements so that researchers and companies in other countries will be able to prepare petitions requesting approval for the import and sale of irradiated foods into North America. (author)

  16. Disruption of ecosystem processes in western North America by invasive species

    OpenAIRE

    Dukes, Jeffrey S.; Mooney, Harold A.

    2004-01-01

    Many ecosystems of western North America have been dramatically changed by non-native species. Here, we review ecological impacts of 56 plant, animal, fungus, and protist species that were brought to this region by humans. We discuss characteristics of invasive species that can lead to major ecosystem impacts, and explore how invasive species alter many different attributes of ecosystems. Specifically, we include examples of invasive species that affect geomorphology, fire regimes, hydrology,...

  17. Competition Between Sports Leagues: Theory and Evidence on Rival League Formation in North America

    OpenAIRE

    Che, X.; Humphreys, B. R.

    2012-01-01

    We analyze the formation of rival leagues and deterrence by incumbent leagues in professional team sports, which is one of the least studied forms of competition in sports. We first survey the economic history of professional sport leagues in North America and develop stylized facts about rival league formation. We then develop a game-theoretical model to explain some of these interesting stylized facts, showing that if the bargaining power of the incumbent league is sufficiently small—i.e., ...

  18. Tracking multi-generational colonization of the breeding grounds by monarch butterflies in eastern North America

    OpenAIRE

    Flockhart, D. T. Tyler; Wassenaar, Leonard I.; Martin, Tara G.; Keith A. Hobson; Wunder, Michael B.; Norris, D. Ryan

    2013-01-01

    Insect migration may involve movements over multiple breeding generations at continental scales, resulting in formidable challenges to their conservation and management. Using distribution models generated from citizen scientist occurrence data and stable-carbon and -hydrogen isotope measurements, we tracked multi-generational colonization of the breeding grounds of monarch butterflies (Danaus plexippus) in eastern North America. We found that monarch breeding occurrence was best modelled wit...

  19. Psychobiography Training in Psychology in North America: Mapping the Field and Charting a Course

    OpenAIRE

    Ponterotto, Joseph G.; Reynolds, Jason D.; Samantha Morel; Linda Cheung

    2015-01-01

    Psychobiography holds an important position in the history of psychology, yet little is known about the status of psychobiographical training and dissertation research in psychology departments. This brief report identified psychobiography courses throughout North America and content analyzed a sample of 65 psychobiography dissertations to discern the theories and methods that have most commonly anchored this research. Results identified few psychology courses specifically in psychobiography,...

  20. Central Wind Forecasting Programs in North America by Regional Transmission Organizations and Electric Utilities: Revised Edition

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J.; Porter, K.

    2011-03-01

    The report and accompanying table addresses the implementation of central wind power forecasting by electric utilities and regional transmission organizations in North America. The first part of the table focuses on electric utilities and regional transmission organizations that have central wind power forecasting in place; the second part focuses on electric utilities and regional transmission organizations that plan to adopt central wind power forecasting in 2010. This is an update of the December 2009 report, NREL/SR-550-46763.

  1. Natural and Human-induced Disturbances and Their Impacts on Forest Carbon Budgets in North America

    Science.gov (United States)

    Pan, Y.; Birdsey, R.; Chen, J. M.; McCullough, K.; Zhang, F.

    2014-12-01

    Natural and human-induced disturbances have profound impacts on forest carbon dynamics, and may cause the greatest uncertainty in estimating forest carbon budgets. In North America, three countries show very different forest disturbance patterns: Canadian forests are dominated by natural disturbances such as wildfires and insect outbreaks; forests of Mexico are more affected by human-induced land disturbances such as land-use change; while US forests are equally affected by human-induced and natural disturbances. As human-induced disturbances are closely linked to socioeconomic factors, natural disturbances are usually viewed as a natural process in forests and have equilibrium impacts on forests over the long run. However, with climate change and related changes in natural disturbance regimes in terms of frequency, intensity and scale, there are now fundamental changes in the nature of the impact of natural disturbances on forest carbon dynamics and even greater uncertainty about forest carbon budgets and feedbacks to the atmosphere and climate. In this study, we synthesize disturbance information for North America based on existing remote-sensing products, ground-based observations and modeling studies, evaluating impacts of disturbances on forest carbon budgets that are relevant to disturbance types, scales, frequency and intensity. The work represents the initial step of a more ambitious project tackling this research challenge for North America that crosses a broad climate gradient and diverse socioeconomic entities. The goal is to ultimately improve the estimates of forest carbon budgets and their potential for climate mitigation under changing environments.

  2. Mitochondrial DNA and prehistoric settlements: native migrations on the western edge of North America.

    Science.gov (United States)

    Eshleman, Jason A; Malhi, Ripan S; Johnson, John R; Kaestle, Frederika A; Lorenz, Joseph; Smith, David Glenn

    2004-02-01

    We analyzed previously reported mtDNA haplogroup frequencies of 577 individuals and hypervariable segment 1 (HVS1) sequences of 265 individuals from Native American tribes in western North America to test hypotheses regarding the settlement of this region. These data were analyzed to determine whether Hokan and Penutian, two hypothesized ancient linguistic stocks, represent biological units as a result of shared ancestry within these respective groups. Although the pattern of mtDNA variation suggests regional continuity and although gene flow between populations has contributed much to the genetic landscape of western North America, some evidence supports the existence of both the Hokan and Penutian phyla. In addition, a comparison between coastal and inland populations along the west coast of North America suggests an ancient coastal migration to the New World. Similarly high levels of haplogroup A among coastal populations in the Northwest and along the California coast as well as shared HVS1 sequences indicate that early migrants to the New World settled along the coast with little gene flow into the interior valleys.

  3. Recent advances in the compilation of holocene relative Sea-level database in North America

    Science.gov (United States)

    Horton, B.; Vacchi, M.; Engelhart, S. E.; Nikitina, D.

    2015-12-01

    Reconstruction of relative sea level (RSL) has implications for investigation of crustal movements, calibration of earth rheology models and the reconstruction of ice sheets. In recent years, efforts were made to create RSL databases following a standardized methodology. These regional databases provided a framework for developing our understanding of the primary mechanisms of RSL change since the Last Glacial Maximum and a long-term baseline against which to gauge changes in sea-level during the 20th century and forecasts for the 21st. Here we present two quality-controlled Holocene RSL database compiled for North America. Along the Pacific coast of North America (British Columbia, Canada to California, USA), our re-evaluation of sea-level indicators from geological and archaeological investigations yield 841 RSL data-points mainly from salt and freshwater wetlands or adjacent estuarine sediment as well as from isolation basin. Along the Atlantic coast of North America (Hudson Bay, Canada to South Carolina, USA), we are currently compiling a database including more than 2000 RSL data-points from isolation basin, salt and freshwater wetlands, beach ridges and intratidal deposits. We outline the difficulties and solutions we made to compile databases in such different depostional environment. We address complex tectonics and the framework to compare such large variability of RSL data-point. We discuss the implications of our results for the glacio-isostatic adjustment (GIA) models in the two studied regions.

  4. Forced genital cutting in North America: feminist theory and nursing considerations.

    Science.gov (United States)

    Antinuk, Kira

    2013-09-01

    This article will examine forced nontherapeutic genital cutting (FNGC) through the lens of feminist theory and in relation to the concept of social justice in nursing. I will address the underlying assumptions of feminism and how they apply to the two currently legal forms of FNGC in North America: male infant circumcision and intersex infant/child genital cutting. Through a literature review and critical analysis of these practices, I will illustrate the challenges they present when considering the role of nurses in promoting social justice. If feminism asserts that bodily integrity, autonomy, and fundamental human rights are essential components of gender equality, it follows that these must be afforded to all genders without discrimination. Historically, there have been few feminists who have made this connection, yet a growing and diverse movement of people is challenging the frameworks in which we consider genital cutting in our society. Nurses are positioned well to be at the forefront of this cause and have a clear ethical duty to advocate for the elimination of all forms of FNGC.

  5. Space-Based Ornithology - Studying Bird Migration and Environmental Change in North America

    Science.gov (United States)

    Smith, James A.; Deppe, Jill L.

    2008-01-01

    Natural fluctuations in the availability of critical stopover sites coupled with anthropogenic destruction of wetlands, land-use change, and anticipated losses due to climate change present migratory birds with a formidable challenge. Space based technology in concert with bird migration modeling and geographical information analysis yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At the NASA Goddard Space Flight Center, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. We use an individual-based bird biophysical migration model, driven by remotely sensed land surface data, climate and hydrologic data, and biological field observations to study migratory bird responses to environmental change in North America. Simulation allows us to study bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. We illustrate our approach by simulating the spring migration of pectoral sandpipers from the Gulf of Mexico to Alaska. Mean stopover length and trajectory patterns are consistent with field observations.

  6. Space-based ornithology: studying bird migration and environmental change in North America

    Science.gov (United States)

    Smith, James A.; Deppe, Jill L.

    2008-10-01

    Natural fluctuations in the availability of critical stopover sites coupled with anthropogenic destruction of wetlands, land-use change, and anticipated losses due to climate change present migratory birds with a formidable challenge. Space based technology in concert with bird migration modeling and geographical information analysis yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At the NASA Goddard Space Flight Center, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. We use an individual-based bird biophysical migration model, driven by remotely sensed land surface data, climate and hydrologic data, and biological field observations to study migratory bird responses to environmental change in North America. Simulation allows us to study bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. We illustrate our approach by simulating the spring migration of pectoral sandpipers from the Gulf of Mexico to Alaska. Mean stopover length and trajectory patterns are consistent with field observations.

  7. Forced genital cutting in North America: feminist theory and nursing considerations.

    Science.gov (United States)

    Antinuk, Kira

    2013-09-01

    This article will examine forced nontherapeutic genital cutting (FNGC) through the lens of feminist theory and in relation to the concept of social justice in nursing. I will address the underlying assumptions of feminism and how they apply to the two currently legal forms of FNGC in North America: male infant circumcision and intersex infant/child genital cutting. Through a literature review and critical analysis of these practices, I will illustrate the challenges they present when considering the role of nurses in promoting social justice. If feminism asserts that bodily integrity, autonomy, and fundamental human rights are essential components of gender equality, it follows that these must be afforded to all genders without discrimination. Historically, there have been few feminists who have made this connection, yet a growing and diverse movement of people is challenging the frameworks in which we consider genital cutting in our society. Nurses are positioned well to be at the forefront of this cause and have a clear ethical duty to advocate for the elimination of all forms of FNGC. PMID:24030105

  8. USGS Small-scale Dataset - Topographic and Bathymetric Shaded Relief of North America 200509 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Topographic and Bathymetric Shaded Relief of North America map layer shows depth and elevation ranges using colors, with relief enhanced by shading. The image...

  9. USGS Small-scale Dataset - Grayscale North America Shaded Relief - 1-Kilometer Resolution 200509 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The grayscale North America shaded relief data were derived from the GTOPO30 elevation data. GTOPO30 is a global digital elevation model (DEM) with a horizontal...

  10. USGS Small-scale Dataset - Color North America Shaded Relief - 1-Kilometer Resolution 200304 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The North America Shaded Relief data were derived from the GTOPO30 elevation data. GTOPO30 is a global digital elevation model (DEM) with a horizontal grid spacing...

  11. Effects of Temperature, Salinity and Seed Age on Induction of Zostera japonica Germination in North America, USA

    Science.gov (United States)

    Seagrasses can colonize unstructured mudflats either through clonal growth or seed germination and survival. Zostera japonica is an introduced seagrass in North America that has rapidly colonized mudflats along the Pacific Coast, leading to active management of the species. Gro...

  12. Deriving long-term sea level variations at tide gauge stations in Atlantic North America

    Science.gov (United States)

    Ince, E. S.; Sideris, M. G.; Rangelova, E.

    2009-05-01

    Tide gauge recording is an indispensable geodetic tool to study local sea level variations in coastal areas and mean sea level trends on a global scale. Combined with satellite altimetry sea surface heights or GNSS- derived ellipsoidal heights, tide gauge records have been used for deriving estimates of vertical crustal motion elsewhere. The objective of our paper is to study the capabilities of the method of singular spectrum analysis, which is generically related to empirical orthogonal functions/principal component analysis technique, to derive local long-term and secular sea level trends. This method allows one to extract any anomalous sea level signals, which is difficult to achieve by the conventional harmonic analysis. We use a set of tide gauge stations in Atlantic Canada and the USA extracted from the monthly PSMSL data base. To create continuous time series, we fill all time gaps by interpolating the main periodic and trend components of the sea level signal using the least squares harmonic analysis. We analyze all tide gauge time series simultaneously through singular value decomposition of the time-lagged series combined in a data trajectory matrix. This enables us to extract and separate the main modes of variability of the local sea level and to study only the long-term spatio-temporal patterns in the sea level variations. Our preliminary results show that the length of the tide gauge time series and the relative contribution of the signals to the total sea level variance are the two crucial factors that may preclude the separation of the local secular sea level fall or rise from any decadal sea level variability. The outcome of our study will be useful for combined satellite altimetry/TG/GRACE studies of sea level changes in the coastal areas, studies of vertical crustal motion due to postglacial rebound in the region, as well as the definition and realization of a dynamic reference surface for orthometric heights in North America.

  13. Identification of Knowledge Gaps Regarding Healthcare Workers' Exposure to Antineoplastic Drugs: Review of Literature, North America versus Europe

    OpenAIRE

    Hon, Chun-Yip; Barzan, Cris; Astrakianakis, George

    2014-01-01

    We have been examining the issue of healthcare workers' exposure to antineoplastic drugs for nearly a decade and have observed that there appears to be more publications on the subject matter originating from Europe than from North America. The concern is that findings from Europe may not be generalizable to North America because of differences in handling practices, regulatory requirements, and training. Our objective was to perform a literature review to confirm our observation and, in turn...

  14. Active Pacific North America Plate boundary tectonics as evidenced by seismicity in the oceanic lithosphere offshore Baja California, Mexico

    Science.gov (United States)

    Hauksson, Egill; Kanamori, Hiroo; Stock, Joann; Cormier, Marie-Helene; Legg, Mark

    2014-03-01

    Pacific Ocean crust west of southwest North America was formed by Cenozoic seafloor spreading between the large Pacific Plate and smaller microplates. The eastern limit of this seafloor, the continent-ocean boundary, is the fossil trench along which the microplates subducted and were mostly destroyed in Miocene time. The Pacific-North America Plate boundary motion today is concentrated on continental fault systems well to the east, and this region of oceanic crust is generally thought to be within the rigid Pacific Plate. Yet, the 2012 December 14 Mw 6.3 earthquake that occurred about 275 km west of Ensenada, Baja California, Mexico, is evidence for continued tectonism in this oceanic part of the Pacific Plate. The preferred main shock centroid depth of 20 km was located close to the bottom of the seismogenic thickness of the young oceanic lithosphere. The focal mechanism, derived from both teleseismic P-wave inversion and W-phase analysis of the main shock waveforms, and the 12 aftershocks of M ˜3-4 are consistent with normal faulting on northeast striking nodal planes, which align with surface mapped extensional tectonic trends such as volcanic features in the region. Previous Global Positioning System (GPS) measurements on offshore islands in the California Continental Borderland had detected some distributed Pacific and North America relative plate motion strain that could extend into the epicentral region. The release of this lithospheric strain along existing zones of weakness is a more likely cause of this seismicity than current thermal contraction of the oceanic lithosphere or volcanism. The main shock caused weak to moderate ground shaking in the coastal zones of southern California, USA, and Baja California, Mexico, but the tsunami was negligible.

  15. What Controls Space-Time Patterns of Magmatism in Western North America: Plate Tectonics, Delamination, or Convection?

    Science.gov (United States)

    Glazner, A. F.

    2007-05-01

    Mesozoic and Cenozoic magmatism in western North America is commonly explained by shallowing and steepening of subduction along the west coast of North America, and progressive destruction of the subduction system by development of the San Andreas transform fault system. This hypothesis makes several specific predictions about space-time patterns of magmatism, including eastward and westward sweeps, development of slab-window magmatism, and progressive northward extinction of an ancestral Cascade arc. However, analysis of space-time patterns using the NAVDAT database indicates that these predicted patterns are curiously obscure in the magmatic record, although other unexplained patterns are strong. Animation of about 29,000 Cenozoic U.S. points from NAVDAT (www.navdat.org) demonstrates that: (1) calc- alkaline, intermediate volcanism is poorly linked to the subduction system; (2) there is little evidence for slab- window magmatism; (3) there was no ancestral Cascade arc south of Oregon until ca. 10 Ma; (4) magmatism shifted from primarily silicic to dominantly basaltic throughout the Miocene; and (5) magmatism was clearly migratory in several directions in ways that cannot be explained by plate-tectonic processes, at length scales ranging from 1000s to 10s of km. Space-time patterns that cannot be readily linked to plate-tectonic control include: (1) a silicic sweep from Montana into Nevada from 50 to 20 Ma; (2) a clockwise sweep around the Colorado Plateau from New Mexico to southern Nevada from about 30 to 15 Ma; (3) a burst of magmatism at about 16 Ma in northern Nevada, followed by outward sweeps to Yellowstone, Oregon, and the Sierra Nevada; (4) progressive encroachment of basaltic magmatism onto the Colorado Plateau, and (5) several local migrations, including from Phoenix north onto the Colorado Plateau and from the San Francisco Bay area north to the Geysers geothermal field. These migrations typically occurred at 20-50 mm/yr. Possible origins include

  16. Reconstructing Hydrologic Variability in Southwestern North America Using Speleothem Proxies and Precipitation Isotopes from California

    Science.gov (United States)

    McCabe-Glynn, Staryl

    Precipitation in southwestern North America has exhibited significant natural variability over the past few thousand years. This variability has been attributed to sea surface temperature regimes in the Pacific and Atlantic oceans, and to the attendant shifts in atmospheric circulation patterns. In particular, decadal variability in the North Pacific has influenced precipitation in this region during the twentieth century, but links to earlier droughts and pluvials are unclear. Here I assess these links using delta18 O measurements from a speleothem from southern California that spans AD 854-- 2007. I show that variations in the oxygen isotopes of the speleothem correlate to sea surface temperatures in the Kuroshio Extension region of the North Pacific, which affect the atmospheric trajectory and isotopic composition of moisture reaching the study site. Interpreting our speleothem data as a record of sea surface temperatures in the Kuroshio Extension, I find a strong 22-year periodicity, suggesting a persistent solar influence on North Pacific decadal variability. A comparison with tree-ring records of precipitation during the past millennium shows that some droughts occurred during periods of warmth in the Kuroshio Extension, similar to the instrumental record. However, other droughts did not and instead were likely influenced by other factors. The carbon isotope record indicates drier conditions are associated with higher delta13C values and may be a suitable proxy for reconstructing past drought variability. More research is needed to determine the controls on trace element concentrations. Finally, I find a significant increase in sea surface temperature variability over the past 150 years, which may reflect an influence of greenhouse gas concentrations on variability in the North Pacific. While drought is a common feature of climate in this region, most climate models also project extreme precipitation events to increase in frequency and severity because the

  17. Projected future distributions of vectors of Trypanosoma cruzi in North America under climate change scenarios.

    Directory of Open Access Journals (Sweden)

    Miroslava Garza

    2014-05-01

    Full Text Available BACKGROUND: Chagas disease kills approximately 45 thousand people annually and affects 10 million people in Latin America and the southern United States. The parasite that causes the disease, Trypanosoma cruzi, can be transmitted by insects of the family Reduviidae, subfamily Triatominae. Any study that attempts to evaluate risk for Chagas disease must focus on the ecology and biogeography of these vectors. Expected distributional shifts of vector species due to climate change are likely to alter spatial patterns of risk of Chagas disease, presumably through northward expansion of high risk areas in North America. METHODOLOGY/PRINCIPAL FINDINGS: We forecast the future (2050 distributions in North America of Triatoma gerstaeckeri and T. sanguisuga, two of the most common triatomine species and important vectors of Trypanosoma cruzi in the southern United States. Our aim was to analyze how climate change might affect the future shift of Chagas disease in North America using a maximum entropy algorithm to predict changes in suitable habitat based on vector occurrence points and predictive environmental variables. Projections based on three different general circulation models (CCCMA, CSIRO, and HADCM3 and two IPCC scenarios (A2 and B2 were analyzed. Twenty models were developed for each case and evaluated via cross-validation. The final model averages result from all twenty of these models. All models had AUC >0.90, which indicates that the models are robust. Our results predict a potential northern shift in the distribution of T. gerstaeckeri and a northern and southern distributional shift of T. sanguisuga from its current range due to climate change. CONCLUSIONS/SIGNIFICANCE: The results of this study provide baseline information for monitoring the northward shift of potential risk from Chagas disease in the face of climate change.

  18. Extreme conditions over Europe and North America: role of the Atlantic Multidecadal Variability

    Science.gov (United States)

    Ruprich-Robert, Yohan; Msadek, Rym; Delworth, Tom

    2016-04-01

    The Atlantic Multidecadal Variability (AMV) is the result and possibly the source of marked modulations of the climate over many areas of the globe. For instance, the relatively warm and dry climate of North America throughout the 30-yr interval of 1931-60, during which the Dust Bowl and the 1950's drought occurred, has been linked to the concomitant warm phase of the AMV. During this period relative warm and wet conditions prevailed over Europe. After 1960, the Atlantic began to cool, and for almost three decades the North American climate turned wetter and cooler whereas Europe experienced cooler and dryer conditions. However, the shortness of the historical observations compared to the AMV period suggested by longer proxy (~60-80yr) does not allow to firmly conclude on the causal effect of the AMV. We use a model approach to isolate the causal role of the AMV on the occurrence of extreme events over Europe and North America. We present experiments based on two GFDL global climate models, a low resolution version, CM2.1 and a higher resolution model for the atmospheric component, FLOR. In both model experiments sea surface temperatures in the North Atlantic sector are restored to the observed AMV pattern, while the other basins are left fully coupled. In order to explore and robustly isolate the AMV impacts on extreme events, we use large ensemble simulations (100 members for CM2.1 and 50 for FLOR) that we run for 20 years. We find that a positive phase of the AMV increases the frequency of occurrence of drought over North America and of extremely cold/warm conditions over Northern/Central Europe during winter/summer. Interestingly, we find that the AMV impacts on these extreme conditions are modulated by the Pacific response to the AMV itself. Members that develop a weak Pacific response show more extreme events over Europe whereas those that develop a strong Pacific response show more extreme events over North America.

  19. The evolution of electricity demand in northeastern North America

    Energy Technology Data Exchange (ETDEWEB)

    Labonte, A.; Lafrance, G.; Swiprenant, J.P

    1990-01-01

    Exploratory scenarios concerning the long-term evolution of electricity demand in the residential, commercial and industrial sectors of the northeastern United States and eastern Canada are presented. The factors affecting the evolution of electricity demand are also compared across regions. The analysis is based on the use of MEDEQ, a model developed by INRS-Energie and the Ministry of Energy and Resources of Quebec. The results show that the market for Quebec's electricity production is substantial. The growth rate of electricity demand should continue to be positive in all of the regions under study. Overall this growth will generate an additional demand for electricity of about 215 TWh per year by 2006, which can be divided among three main markets of approximately the same size: Quebec, Ontario, and the northeastern States. Any increase in the share of electricity in Quebec must overcome the fact that electricity is already the most important source of energy in the province. Since the share of electricity is much further away from any saturation point in other regions, it seems reasonable to conclude that these other regions offer good prospects for market expansion for Quebec electricity, especially if electricity prices become more competitive. All of the results confirm the hypothesis that the development of Quebec's remaining hydroelectric power potential is not limited by demand. 13 refs., 8 tabs

  20. Outlook for ethylene industry worldwide and in North America: Positioning Canada

    International Nuclear Information System (INIS)

    The current state of the Alberta and world petrochemical marketplace is reviewed, including the attributes needed to stay competitive, the place of Alberta in this picture, and the outlook for the future. As part of this review, the demand for ethylene in the various regions of the world is analyzed and projected ten years forward. Largest growth is forecast for the Far East with a lower growth rate, but still significant increases in volume in North America and Europe. Recent structural developments in the industry are analyzed, including the emergence of formidable competitors from resource-rich regions of the Middle East, and the factors responsible for assuring success in competing, i.e. net feedstock cost, or the difference between the cost of the feedstock less co-product credits. As far as Alberta is concerned, the primary opportunities lie mostly in North America with some opportunities in the Far East, although facing stiff competition there from Middle East producers in Far Eastern markets. Rail transportation to port and ocean shipping to reach these markets are also high. Filling the recently increased pipeline capacity will continue to be a challenge to producers, as will the ethane content of future gas supplies relative to the past. The implications of the Alliance Pipeline and the construction of the Aux Sable gas plant and fractionator in the Chicago area are as yet unclear, but all factors taken together indicate that olefins production in Alberta will continue to be competitive in North American markets, although less so than in the past. Further expansion of the industry in Alberta is unlikely; indeed, any growth of the industry is likely to be exported to the United States. Strong competition from resource-rich areas outside of North America, higher ethane costs and high transportation costs to reach these markets will be the important challenges if Alberta's competitive position in world markets is to be sustained

  1. Avian mercury exposure and toxicological risk across western North America: A synthesis

    Science.gov (United States)

    Ackerman, Josh; Eagles-Smith, Collin A.; Herzog, Mark; Hartman, Christopher; Peterson, Sarah; Evers, David C.; Jackson, Allyson K.; Elliott, John E.; Vander Pol, Stacy S.; Bryan, Colleen E.

    2016-01-01

    Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total, 29219 original bird mercury concentrations from 225 species were compiled, and an additional 1712 mean mercury concentrations, representing 19998 individuals and 176 species, from 200 publications were obtained. To make mercury data comparable across bird tissues, published equations of tissue mercury correlations were used to convert all mercury concentrations into blood-equivalent mercury concentrations. Blood-equivalent mercury concentrations differed among species, foraging guilds, habitat types, locations, and ecoregions. Piscivores and carnivores exhibited the greatest mercury concentrations, whereas herbivores and granivores exhibited the lowest mercury concentrations. Bird mercury concentrations were greatest in ocean and salt marsh habitats and lowest in terrestrial habitats. Bird mercury concentrations were above toxicity benchmarks in many areas throughout western North America, and multiple hotspots were identified. Additionally, published toxicity benchmarks established in multiple tissues were summarized and translated into a common blood-equivalent mercury concentration. Overall, 66% of birds sampled in western North American exceeded a blood-equivalent mercury concentration of 0.2 μg/g wet weight (ww; above background levels), which is the lowest-observed effect level, 28% exceeded 1.0 μg/g ww (moderate risk), 8% exceeded 3.0 μg/g ww (high risk), and 4% exceeded 4.0 μg/g ww (severe risk). Mercury monitoring programs should sample bird tissues, such as adult blood and eggs, that are most-easily translated into tissues with well-developed toxicity benchmarks and that

  2. Palinspastic restoration of NAVDat and implications for the origin of magmatism in southwestern North America

    Science.gov (United States)

    McQuarrie, Nadine; Oskin, Michael

    2010-10-01

    Simultaneous palinspastic restoration of deformation and volcanism illuminates relationships between magmatism and tectonics in western North America. Using ArcGIS, we retrodeformed the NAVDat (North American Volcanic Database, navdat.geongrid.org) using the western North America reconstruction of McQuarrie and Wernicke (2005). From these data sets we quantitatively compare rates of magmatism and deformation and evaluate the age, composition, and migration of Cenozoic volcanism from 36 Ma to present. These relationships are shown in a series of palinspastic maps as well as animations that highlight migrating extension and volcanism with time. Western North America is grouped into eight different regions with distinct relationships between strain and volcanism to evaluate competing hypotheses regarding the relationship of extension to continental magmatism. A first-order observation from this study is that magmatism throughout the Basin and Range appears to be primarily driven by plate boundary effects, notably subducting and foundering slabs as well as slab windows. Exceptions include the Yellowstone hotspot system along the northern border of our study area and late-stage (<8 Ma) passive, extension-related asthenospheric upwelling along the eastern and western margins of the Basin and Range. The palinspastic reconstructions presented here highlight that the classic, high-angle, Basin and Range faulting that comprises most of the physiographic Basin and Range Province commenced during a magmatic lull. More broadly, with the exception of the Rio Grande rift we find that pulses of magmatism lag the onset of extension. These observations largely contradict the active rifting model where magmatism triggers Basin and Range extension.

  3. Summertime influence of Asian pollution in the free troposphere over North America

    Science.gov (United States)

    Liang, Q.; Jaeglé, L.; Hudman, R. C.; Turquety, S.; Jacob, D. J.; Avery, M. A.; Browell, E. V.; Sachse, G. W.; Blake, D. R.; Brune, W.; Ren, X.; Cohen, R. C.; Dibb, J. E.; Fried, A.; Fuelberg, H.; Porter, M.; Heikes, B. G.; Huey, G.; Singh, H. B.; Wennberg, P. O.

    2007-06-01

    We analyze aircraft observations obtained during INTEX-A (1 July to 14 August 2004) to examine the summertime influence of Asian pollution in the free troposphere over North America. By applying correlation analysis and principal component analysis (PCA) to the observations between 6 and 12 km, we find dominant influences from recent convection and lightning (13% of observations), Asia (7%), the lower stratosphere (7%), and boreal forest fires (2%), with the remaining 71% assigned to background. Asian air masses are marked by high levels of CO, O3, HCN, PAN, C2H2, C6H6, methanol, and SO42-. The partitioning of NOy species in the Asian plumes is dominated by PAN (˜600 pptv), with varying NOx/HNO3 ratios in individual plumes, consistent with individual transit times of 3-9 days. Export of Asian pollution occurred in warm conveyor belts of midlatitude cyclones, deep convection, and in typhoons. Compared to Asian outflow measurements during spring, INTEX-A observations display lower levels of anthropogenic pollutants (CO, C3H8, C2H6, C6H6) due to shorter summer lifetimes; higher levels of biogenic tracers (methanol and acetone) because of a more active biosphere; and higher levels of PAN, NOx, HNO3, and O3 reflecting active photochemistry, possibly enhanced by efficient NOy export and lightning. The high ΔO3/ΔCO ratio (0.76 mol/mol) in Asian plumes during INTEX-A is due to strong photochemical production and, in some cases, mixing with stratospheric air along isentropic surfaces. The GEOS-Chem global model captures the timing and location of the Asian plumes. However, it significantly underestimates the magnitude of observed enhancements in CO, O3, PAN and NOx.

  4. Summertime Influence of Asian Pollution in the Free Troposphere over North America

    Science.gov (United States)

    Liang, Q.; Jaegle, Lyatt; Hudman, Rynda C.; Turquety, Solene; Jacob, Daniel J.; Avery, Melody A.; Blake, Donald R.; Browell, Edward V.; Sachse, Glen W.; Brune, W. H.; Ren, Xinrong; Clarke, A.; Cohen, R.; Dibb, Jack; Fried, Alan; Fuelberg, Henry; Porter, M.; Heikes, Brian; Huey, Greg; Singh, H. B.; Wennberg, Paul

    2007-01-01

    We analyze aircraft observations obtained during INTEX-A (1 July 14 - August 2004) to examine the summertime influence of Asian pollution in the free troposphere over North America. By applying correlation analysis and Principal Component Analysis (PCA) to the observations between 6-12 km, we find dominant influences from recent convection and lightning (13 percent of observations), Asia (7 percent), the lower stratosphere (7 percent), and boreal forest fires (2 percent), with the remaining 71 percent assigned to background. Asian airmasses are marked by high levels of CO, O3, HCN, PAN, acetylene, benzene, methanol, and SO4(2-). The partitioning of reactive nitrogen species in the Asian plumes is dominated by peroxyacetyl nitrate (PAN) (approximately 600 pptv), with varying NO(x)/HNO3 ratios in individual plumes consistent with different plumes ages ranging from 3 to 9 days. Export of Asian pollution in warm conveyor belts of mid-latitude cyclones, deep convection, and lifting in typhoons all contributed to the five major Asian pollution plumes. Compared to past measurement campaigns of Asian outflow during spring, INTEX-A observations display unique characteristics: lower levels of anthropogenic pollutants (CO, propane, ethane, benzene) due to their shorter summer lifetimes; higher levels of biogenic tracers (methanol and acetone) because of a more active biosphere; as well as higher levels of PAN, NO(x), HNO3, and O3 (more active photochemistry possibly enhanced by injection of lightning NO(x)). The high delta O3/delta CO ratio (0.76 mol mol(exp -1)) of Asian plumes during INTEX-A is due to a combination of strong photochemical production and mixing with stratospheric air along isentropic surfaces. The GEOS-Chem global chemical transport model captures the timing and location of the Asian plumes remarkably well. However, it significantly underestimates the magnitude of the enhancements.

  5. 76 FR 51468 - BMW of North America, LLC, a subsidiary of BMW AG, Receipt of Petition for Decision of...

    Science.gov (United States)

    2011-08-18

    ..., (65 FR 19477-78). The petition, supporting materials, and all comments received before the close of... National Highway Traffic Safety Administration BMW of North America, LLC, a subsidiary of BMW AG, Receipt... Administration, DOT. ACTION: Receipt of Petition for Inconsequential Noncompliance. SUMMARY: BMW of North...

  6. First report of Taenia arctos (Cestoda: Taeniidae) from grizzly (Ursus arctos horribilis) and black bears (Ursus americanus) in North America.

    Science.gov (United States)

    Catalano, Stefano; Lejeune, Manigandan; Verocai, Guilherme G; Duignan, Pádraig J

    2014-04-01

    The cestode Taenia arctos was found at necropsy in the small intestine of a grizzly (Ursus arctos horribilis) and a black bear (Ursus americanus) from Kananaskis Country in southwestern Alberta, Canada. The autolysis of the tapeworm specimens precluded detailed morphological characterization of the parasites but molecular analysis based on mitochondrial DNA cytochrome c oxidase subunit 1 gene confirmed their identity as T. arctos. This is the first report of T. arctos from definitive hosts in North America. Its detection in Canadian grizzly and black bears further supports the Holarctic distribution of this tapeworm species and its specificity for ursids as final hosts. Previously, T. arctos was unambiguously described at its adult stage in brown bears (Ursus arctos arctos) from Finland, and as larval stages in Eurasian elk (Alces alces) from Finland and moose (Alces americanus) from Alaska, USA. Given the morphological similarity between T. arctos and other Taenia species, the present study underlines the potential for misidentification of tapeworm taxa in previous parasitological reports from bears and moose across North America. The biogeographical history of both definitive and intermediate hosts in the Holarctic suggests an ancient interaction between U. arctos, Alces spp., and T. arctos, and a relatively recent host-switching event in U. americanus.

  7. Extra-regional residence time as a correlate of plant invasiveness: European archaeophytes in North America.

    Science.gov (United States)

    La Sorte, Frank A; Pysek, Petr

    2009-09-01

    Human activities have degraded biogeographical barriers to dispersal resulting in the spread and naturalization of increasing numbers of nonnative invasive species. One correlate of invasiveness within a region is residence time or time since introduction. Plant species that were introduced into Europe prior to AD 1500 (European archaeophytes) that were subsequently introduced into North America provide a unique opportunity to examine the effect of extra-regional residence time (i.e., residence time that occurred in a nonnative region before a species was introduced into a new region). Here, we examine how nonnative species with extensive extra-regional residence times have affected beta diversity among states in the contiguous United States of America based on an analysis of occupancy and distance decay of similarity. State floras contained an average of 3106 +/- 922 species (mean +/- SD) with 2318 +/- 757 species classified as native, 180 +/- 43 species as European archaeophyte, and 608 -236 species as other exotic with no European archaeophyte association. For European archaeophytes, 42% were identified as noxious weeds in the United States with 8% identified as agricultural and 14% as natural-area weeds (20%, 2%, and 13% for other exotics, respectively). In strong contrast to natives and other exotics, European archaeophytes were more widespread and presented weaker distance-decay patterns. Thus, European archaeophytes were more likely to become noxious weeds, particularly within agricultural areas, and were associated with significant losses in beta diversity. We suggest that this outcome is a consequence of extra-regional residence time, which allowed for the selection of species or the evolution of traits that favored the colonization of arable habitats associated with early agricultural activities in Europe, habitats that are widespread, resource rich, and uniformly distributed in the United States. Our findings suggest that a long-term trajectory can be

  8. Chronic lead exposure is epidemic in obligate scavenger populations in eastern North America.

    Science.gov (United States)

    Behmke, Shannon; Fallon, Jesse; Duerr, Adam E; Lehner, Andreas; Buchweitz, John; Katzner, Todd

    2015-06-01

    Lead is a prominent and highly toxic contaminant with important impacts to wildlife. To understand the degree to which wildlife populations are chronically exposed, we quantified lead levels within American black vultures (Coragyps atratus; BLVU) and turkey vultures (Cathartes aura; TUVU), two species that are useful as environmental sentinels in eastern North America. Every individual sampled (n=108) had bone lead levels indicative of chronic exposure to anthropogenic lead (BLVU: x¯=36.99 ± 55.21 mg Pb/kg tissue (±SD); TUVU: x¯=23.02 ± 18.77 mg/kg). Only a few showed evidence of recent lead exposure (BLVU liver: x¯=0.78 ± 0.93 mg/kg; TUVU liver: x¯=0.55 ± 0.34 mg/kg). Isotopic ratios suggested multiple potential sources of lead including ammunition, gasoline, coal-fired power plants, and zinc smelting. Black and turkey vultures range across eastern North America, from Quebec to Florida and individuals may traverse thousands of kilometers annually. The extent to which vultures are exposed suggests that anthropogenic lead permeates eastern North American ecosystems to a previously unrecognized degree. Discovery of an epidemic of chronic lead exposure in such widespread and common species and the failure of soft-tissue sampling to diagnose this pattern has dramatic implications for understanding modern wildlife and human health concerns. PMID:25795925

  9. Thermal state of permafrost in North America: A contribution to the international polar year

    Science.gov (United States)

    Smith, S.L.; Romanovsky, V.E.; Lewkowicz, A.G.; Burn, C.R.; Allard, M.; Clow, G.D.; Yoshikawa, K.; Throop, J.

    2010-01-01

    A snapshot of the thermal state of permafrost in northern North America during the International Polar Year (IPY) was developed using ground temperature data collected from 350 boreholes. More than half these were established during IPY to enhance the network in sparsely monitored regions. The measurement sites span a diverse range of ecoclimatic and geological conditions across the continent and are at various elevations within the Cordillera. The ground temperatures within the discontinuous permafrost zone are generally above -3°C, and range down to -15°C in the continuous zone. Ground temperature envelopes vary according to substrate, with shallow depths of zero annual amplitude for peat and mineral soils, and much greater depths for bedrock. New monitoring sites in the mountains of southern and central Yukon suggest that permafrost may be limited in extent. In concert with regional air temperatures, permafrost has generally been warming across North America for the past several decades, as indicated by measurements from the western Arctic since the 1970s and from parts of eastern Canada since the early 1990s. The rates of ground warming have been variable, but are generally greater north of the treeline. Latent heat effects in the southern discontinuous zone dominate the permafrost thermal regime close to 0°C and allow permafrost to persist under a warming climate. Consequently, the spatial diversity of permafrost thermal conditions is decreasing over time.

  10. Handymen, Hippies and Healing: Social Transformation through the DIY Movement (1940s to 1970s) in North America

    OpenAIRE

    Smith, Cathy D

    2014-01-01

    This paper explores the relation between the ‘DIY’ (‘do-it-yourself’) movement and ‘DIY architecture’, and the notion of social transformation, in examples of DIY manuals and discourse of North America drawn from the 1940s to the 1970s. The DIY movement emerged as a significant phenomenon in North America of the 1950s, where it was associated with a mainstream audience and a residential market. By the 1960s, the DIY approach was embraced by the North American counterculture as a self-sustaini...

  11. Abatement of atmospheric emissions in North America: Progress to date and promise for the future

    International Nuclear Information System (INIS)

    Much progress has been made in acidic rain abatement in North America. This progress is examined with a focus on man-made emissions of sulfur dioxide and nitrogen oxides that contribute to acidic deposition. A review of US historical trends of SO2 and nitrogen oxides emissions since 1900 and projections of future emissions through the end of this century shoe emissions of SO2 decreasing from a peak in 1970 of 29 Tg/yr to about 26 Tg/yr, but nitrogen oxides emissions continuing an upward trend to about 25 Tg/yr. In Canada, SO2, NO and NO2 emissions are less than 20% of those in the US, and the trends are similar, with SO2 showing future decreases and NO and NO2 continuing to increase. Future industry in North America is expected to emit much lower levels of SO2, NO, and NO2. Technology is also available to limit nitrogen oxides emissions from future motor vehicles. Recent acidic deposition legislation in the US Congress to reduce electric utility and industrial emissions of SO2 by 9 to 13 Tg/yr is reviewed. The estimates of the cost to implement the proposals range from $2 billion to $23 billion over a 5-year period. Retrofitting existing utility and industrial boilers for maximum SO2, NO, and NO2 reduction carries the highest price tag. Several environmental policy options are explored for preventing emission increases and also promoting decreases in future emissions of SO2, NO, and NO2 in North America. Focus on nitrogen oxides emissions may be critical because population growth could cause significant increases in NO and NO2 from motor vehicle use

  12. A 1,200-year perspective of 21st century drought in southwestern North America.

    Science.gov (United States)

    Woodhouse, Connie A; Meko, David M; MacDonald, Glen M; Stahle, Dave W; Cook, Edward R

    2010-12-14

    A key feature of anticipated 21st century droughts in Southwest North America is the concurrence of elevated temperatures and increased aridity. Instrumental records and paleoclimatic evidence for past prolonged drought in the Southwest that coincide with elevated temperatures can be assessed to provide insights on temperature-drought relations and to develop worst-case scenarios for the future. In particular, during the medieval period, ∼AD 900-1300, the Northern Hemisphere experienced temperatures warmer than all but the most recent decades. Paleoclimatic and model data indicate increased temperatures in western North America of approximately 1 °C over the long-term mean. This was a period of extensive and persistent aridity over western North America. Paleoclimatic evidence suggests drought in the mid-12th century far exceeded the severity, duration, and extent of subsequent droughts. The driest decade of this drought was anomalously warm, though not as warm as the late 20th and early 21st centuries. The convergence of prolonged warming and arid conditions suggests the mid-12th century may serve as a conservative analogue for severe droughts that might occur in the future. The severity, extent, and persistence of the 12th century drought that occurred under natural climate variability, have important implications for water resource management. The causes of past and future drought will not be identical but warm droughts, inferred from paleoclimatic records, demonstrate the plausibility of extensive, severe droughts, provide a long-term perspective on the ongoing drought conditions in the Southwest, and suggest the need for regional sustainability planning for the future.

  13. Outflows, dusty cores, and a burst of star formation in the North America and Pelican nebulae

    Energy Technology Data Exchange (ETDEWEB)

    Bally, John [Department of Astrophysical and Planetary Sciences, University of Colorado, UCB 389, Boulder, CO 80309 (United States); Ginsburg, Adam [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching bei Munchen (Germany); Probst, Ron [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Reipurth, Bo [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii at Manoa, 640 North A' ohoku Place, Hilo, HI 96720 (United States); Shirley, Yancy L. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Stringfellow, Guy S., E-mail: John.Bally@colorado.edu, E-mail: aginsburg@eso.org, E-mail: probst@noao.edu, E-mail: reipurth@ifa.hawaii.edu, E-mail: yshirley@as.arizona.edu, E-mail: Guy.Stringfellow@colorado.edu [Center for Astrophysics and Space Astronomy, University of Colorado, UCB 389, Boulder, CO 80309 (United States)

    2014-12-01

    We present observations of near-infrared 2.12 μm molecular hydrogen outflows emerging from 1.1 mm dust continuum clumps in the North America and Pelican Nebula (NAP) complex selected from the Bolocam Galactic Plane Survey (BGPS). Hundreds of individual shocks powered by over 50 outflows from young stars are identified, indicating that the dusty molecular clumps surrounding the NGC 7000/IC 5070/W80 H II region are among the most active sites of ongoing star formation in the solar vicinity. A spectacular X-shaped outflow, MHO 3400, emerges from a young star system embedded in a dense clump more than a parsec from the ionization front associated with the Pelican Nebula (IC 5070). Suspected to be a binary, the source drives a pair of outflows with orientations differing by 80°. Each flow exhibits S-shaped symmetry and multiple shocks indicating a pulsed and precessing jet. The 'Gulf of Mexico', located south of the North America Nebula (NGC 7000), contains a dense cluster of molecular hydrogen objects (MHOs), Herbig-Haro (HH) objects, and over 300 young stellar objects (YSOs), indicating a recent burst of star formation. The largest outflow detected thus far in the North America and Pelican Nebula complex, the 1.6 parsec long MHO 3417 flow, emerges from a 500 M {sub ☉} BGPS clump and may be powered by a forming massive star. Several prominent outflows such as MHO 3427 appear to be powered by highly embedded YSOs only visible at λ > 70 μm. An 'activity index' formed by dividing the number of shocks by the mass of the cloud containing their source stars is used to estimate the relative evolutionary states of Bolocam clumps. Outflows can be used as indicators of the evolutionary state of clumps detected in millimeter and submillimeter dust continuum surveys.

  14. Map service: Database of the Geologic Map of North America- Adapted from the Map by J.C. Reed, Jr. and others (2005)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer contains geologic unit boundaries for the area depicted in the Geologic Map of North America, published by the Geological Society of America in 2005...

  15. Historical changes in the annual number of large floods in North America and Europe

    Science.gov (United States)

    Hodgkins, G. A.; Whitfield, P. H.; Hannaford, J.; Burn, D. H.; Renard, B.; Stahl, K.; Fleig, A.; Madsen, H.; Mediero, L.; Korhonen, J.; Murphy, C.; Crochet, P.; Wilson, D.

    2013-12-01

    Many studies have analyzed historical changes in low magnitude floods, such as the annual peak flow, at a national or regional scale. However, the river basins used have often been influenced by human alterations such as reservoir regulation or urbanization. No known studies have analyzed changes in large floods (greater than 25-year return period) at a continental scale for minimally impacted basins. To fill this research gap, this study analyzed flood flows from reference hydrologic networks (RHNs) or RHN-like gauges in North America (United States and Canada) and Europe (United Kingdom, Ireland, France, Spain, Germany, Switzerland, Austria, Iceland, Norway, Denmark, Sweden, and Finland). RHNs are formally defined networks in several countries that comprise gauging stations with a natural or near-natural flow regime and provide good quality data. Selected RHN-like gauges were included following a major effort to ensure RHN-like status through consultation with local experts. Peak flows with recurrence intervals of 25, 50, and 100 years were estimated using consistent methods for over 1200 study gauges, and peak flows at each gauge that exceeded these flood thresholds in the last 40-100 years were compiled. Continental and regional trends over time in the annual number of large floods, with regions differentiated by type of hydrological regime (pluvial, nival, mixed), are being computed and will be presented at AGU. The unique dataset used for this study is an example of successful international collaboration on hydro-climatic data exchange, which is potentially a step towards establishing RHN or RHN-like networks on a global scale. Analysis of flows from such networks would make a valuable contribution to the understanding of historical global hydrological change and would help inform expected future hydrologic changes.

  16. Avian influenza at both ends of a migratory flyway: characterizing viral genomic diversity to optimize surveillance plans for North America

    Science.gov (United States)

    Pearce, John M.; Ramey, Andrew M.; Flint, Paul L.; Koehler, Anson V.; Fleskes, Joseph P.; Franson, J. Christian; Hall, Jeffrey S.; Derksen, Dirk V.; Ip, Hon S.

    2009-01-01

    Although continental populations of avian influenza viruses are genetically distinct, transcontinental reassortment in low pathogenic avian influenza (LPAI) viruses has been detected in migratory birds. Thus, genomic analyses of LPAI viruses could serve as an approach to prioritize species and regions targeted by North American surveillance activities for foreign origin highly pathogenic avian influenza (HPAI). To assess the applicability of this approach, we conducted a phylogenetic and population genetic analysis of 68 viral genomes isolated from the northern pintail (Anas acuta) at opposite ends of the Pacific migratory flyway in North America. We found limited evidence for Asian LPAI lineages on wintering areas used by northern pintails in California in contrast to a higher frequency on breeding locales of Alaska. Our results indicate that the number of Asian LPAI lineages observed in Alaskan northern pintails, and the nucleotide composition of LPAI lineages, is not maintained through fall migration. Accordingly, our data indicate that surveillance of Pacific Flyway northern pintails to detect foreign avian influenza viruses would be most effective in Alaska. North American surveillance plans could be optimized through an analysis of LPAI genomics from species that demonstrate evolutionary linkages with European or Asian lineages and in regions that have overlapping migratory flyways with areas of HPAI outbreaks.

  17. Problemi di comunicazione interculturale tra Italiani e parlanti di italiano in Nord America (Intercultural Communication Problems Between Italians and Speakers of Italian in North America).

    Science.gov (United States)

    Balboni, Paolo E.

    2001-01-01

    Examines intercultural communication between Italians and speakers of Italian in North America. Argues intercultural communicative competence comprises three elements: deep cultural values or "mental software"; non-verbal means of communication; and language. Offers advice to teachers of Italian who want to help their students develop…

  18. The status of UV/EB curable product in North America: 1998-1999

    International Nuclear Information System (INIS)

    This author has previously reported survey results showing that the use of UV/EB materials has grown at a compound rate of about 10% per annum over the last decade. Together, with about 130 members of RadTech International North America, representing 90 organizations, we have updated and assessed the growth and activities of the industry. The panelists represent a cross section of end users, raw material and equipment suppliers, as well as formulators and consultants. Using a modified Delphi process with five separate survey rounds, a reasonable assessment was made of the advantages, disadvantages, growth rate and growth opportunities of this exciting technology

  19. On plate tectonics and the geologic evolution of southwestern North America

    Science.gov (United States)

    Ward, P.L.

    1991-01-01

    Very rapid subduction of the Farallon plate under southwestern North America between 60 and 40 Ma was accompanied by a relatively low volume of magmatism throughout the southwestern United States and northern Mexico. Between 40 and 20 Ma, when subduction slowed significantly and in one area may have even stopped, magmatism became widespread and voluminous from Nevada and Utah to central Mexico. This correlation of rapid subduction with a relatively low volume of magmatism can be explained by the observation that subduction-related andesitic arc volcanism, often formed in a Laramide-style compressional regime, is relatively low volume compared to continental volcanism. -from Author

  20. Phylodynamics of HIV-1 from a Phase III AIDS vaccine trial in North America

    OpenAIRE

    Perez-Losada, M.; Jobes, D. V.; Sinangil, F.; Crandall, K. A.; Posada, D; Berman, P.W.

    2010-01-01

    In 2003, a phase III placebo-controlled trial (VAX004) of a candidate HIV-1 vaccine (AIDSVAX B/B) was completed in 5,403 volunteers at high risk for HIV-1 infection from North America and the Netherlands. A total of 368 individuals became infected with HIV-1 during the trial. The envelope glycoprotein gene (gp120) from the HIV-1 subtype B viruses infecting 349 patients was sequenced from clinical samples taken as close as possible to the time of diagnosis, rendering a final data set of 1,047 ...

  1. Monarch butterflies cross the Appalachians from the west to recolonize the east coast of North America

    OpenAIRE

    Miller, Nathan G.; Wassenaar, Leonard I.; Keith A. Hobson; Norris, D. Ryan

    2010-01-01

    Each spring, millions of monarch butterflies (Danaus plexippus) migrate from overwintering sites in Mexico to recolonize eastern North America. However, few monarchs are found along the east coast of the USA until mid-summer. Brower (Brower, L. P. 1996 J. Exp. Biol. 199, 93–103.) proposed that east coast recolonization is accomplished by individuals migrating from the west over the Appalachians, but to date no evidence exists to support this hypothesis. We used hydrogen (δD) and carbon (δ13C)...

  2. Variation in cardiac glycoside content of monarch butterflies from natural populations in eastern North America.

    Science.gov (United States)

    Brower, L P; McEvoy, P B; Williamson, K L; Flannery, M A

    1972-08-01

    A new spectrophotometric assay has been used to determine the gross concentration of cardiac glycoside in individual monarch butterflies. Adults sampled during the fall migration in four areas of eastern North America exhibited a wide variation in cardiac glycoside concentration. The correlation between spectrophotometrically measured concentrations and emetic dose determinations supports the existence of a broad palatability spectrum in wild monarch butterflies. The cardiac gylcoside concentration is greater in females than in males and is independent of the dry weight of the butterflies; contrary to prediction, both the concentration mean and variance decrease southward. The defensive advantage of incorporating cardiac glycosides may be balanced by detrimental effects on individual viability. PMID:5043141

  3. Attribution of spatial and temporal variations in terrestrial methane flux over North America

    Directory of Open Access Journals (Sweden)

    X. F. Xu

    2010-07-01

    Full Text Available The attribution of spatial and temporal variations in terrestrial methane (CH4 flux is essential for assessing and mitigating CH4 emission from terrestrial ecosystems. In this study, we used a process-based model, the Dynamic Land Ecosystem Model (DLEM, in conjunction with spatial data of six major environmental factors to attribute the spatial and temporal variations in the terrestrial methane (CH4 flux over North America from 1979 to 2008 to six individual factors and their interaction. Over the past three decades, our simulation indicates that global change factors accumulatively contributed 43.05 Tg CH4-C (1 Tg = 1012 g emission over North America, among which ozone (O3 pollution led to a reduced CH4 emission by 2.69 Tg CH4-C, all other factors including climate variability, nitrogen (N deposition, rising atmospheric carbon dioxide (CO2, N fertilization, and land conversion increased terrestrial CH4 emissions by 40.37 Tg CH4-C, 0.42 Tg CH4-C, 6.95 Tg CH4-C, 0.11 Tg CH4-C, and 3.70 Tg CH4-C, respectively, and interaction between/among these global change factors led to a decline of CH4 emission by 5.80 Tg CH4-C. Climatic variability dominated the inter-annual variations in terrestrial CH4 fluxes at both continental and country levels. The relative importance of each environmental factor in determining the magnitude of methane flux shows substantially spatial variation across North America. This factorial attribution of CH4 fluxes over the North America might benefit policy makers who would like to curb climate warming by reducing CH4 emission.

  4. A regional high-resolution carbon flux inversion of North America for 2004

    Directory of Open Access Journals (Sweden)

    A. E. Schuh

    2009-11-01

    Full Text Available Resolving the discrepancies between NEE estimates based upon (1 ground studies and (2 atmospheric inversion results, demands increasingly sophisticated techniques. In this paper we present a high-resolution inversion based upon a regional meteorology model (RAMS and an underlying biosphere (SiB3 model, both running on an identical 40 km grid over most of North America. Previous papers have utilized inversion regions formed by collapsing biome-similar grid cells into large aggregated regions. The effect of this is that the NEE correction imposed on forested regions on the east coast of the United States might be the same as that imposed on forests on the west coast of the United States while, in reality, there likely exist subtle differences in the two areas, both natural and anthropogenic. Our current inversion framework utilizes a combination of previously employed inversion techniques while allowing carbon flux corrections to be biome independent. Temporally and spatially high-resolution results utilizing biome-independent corrections provide insight into carbon dynamics in North America. In particular, we analyze hourly CO2 mixing ratio data from a sparse network of eight towers in North America for 2004. A prior estimate of carbon fluxes due to gross primary productivity (GPP and ecosystem respiration (ER is constructed from the SiB3 biosphere model on a 40 km grid. A combination of transport from the RAMS and the parameterized chemical transport model (PCTM models is used to forge a connection between upwind biosphere fluxes and downwind observed CO2 mixing ratio data. A Kalman filter procedure is used to estimate weekly corrections to biosphere fluxes based upon observed CO2. RMSE-weighted annual NEE estimates, over an ensemble of potential inversion parameter sets, show a mean estimate 0.57 Pg/yr sink in North America. We perform the inversion with two independently derived boundary inflow

  5. A regional high-resolution carbon flux inversion of North America for 2004

    Science.gov (United States)

    Schuh, A. E.; Denning, A. S.; Corbin, K. D.; Baker, I. T.; Uliasz, M.; Parazoo, N.; Andrews, A. E.; Worthy, D. E. J.

    2010-05-01

    Resolving the discrepancies between NEE estimates based upon (1) ground studies and (2) atmospheric inversion results, demands increasingly sophisticated techniques. In this paper we present a high-resolution inversion based upon a regional meteorology model (RAMS) and an underlying biosphere (SiB3) model, both running on an identical 40 km grid over most of North America. Current operational systems like CarbonTracker as well as many previous global inversions including the Transcom suite of inversions have utilized inversion regions formed by collapsing biome-similar grid cells into larger aggregated regions. An extreme example of this might be where corrections to NEE imposed on forested regions on the east coast of the United States might be the same as that imposed on forests on the west coast of the United States while, in reality, there likely exist subtle differences in the two areas, both natural and anthropogenic. Our current inversion framework utilizes a combination of previously employed inversion techniques while allowing carbon flux corrections to be biome independent. Temporally and spatially high-resolution results utilizing biome-independent corrections provide insight into carbon dynamics in North America. In particular, we analyze hourly CO2 mixing ratio data from a sparse network of eight towers in North America for 2004. A prior estimate of carbon fluxes due to Gross Primary Productivity (GPP) and Ecosystem Respiration (ER) is constructed from the SiB3 biosphere model on a 40 km grid. A combination of transport from the RAMS and the Parameterized Chemical Transport Model (PCTM) models is used to forge a connection between upwind biosphere fluxes and downwind observed CO2 mixing ratio data. A Kalman filter procedure is used to estimate weekly corrections to biosphere fluxes based upon observed CO2. RMSE-weighted annual NEE estimates, over an ensemble of potential inversion parameter sets, show a mean estimate 0.57 Pg/yr sink in North America

  6. A regional high-resolution carbon flux inversion of North America for 2004

    Directory of Open Access Journals (Sweden)

    A. E. Schuh

    2010-05-01

    Full Text Available Resolving the discrepancies between NEE estimates based upon (1 ground studies and (2 atmospheric inversion results, demands increasingly sophisticated techniques. In this paper we present a high-resolution inversion based upon a regional meteorology model (RAMS and an underlying biosphere (SiB3 model, both running on an identical 40 km grid over most of North America. Current operational systems like CarbonTracker as well as many previous global inversions including the Transcom suite of inversions have utilized inversion regions formed by collapsing biome-similar grid cells into larger aggregated regions. An extreme example of this might be where corrections to NEE imposed on forested regions on the east coast of the United States might be the same as that imposed on forests on the west coast of the United States while, in reality, there likely exist subtle differences in the two areas, both natural and anthropogenic. Our current inversion framework utilizes a combination of previously employed inversion techniques while allowing carbon flux corrections to be biome independent. Temporally and spatially high-resolution results utilizing biome-independent corrections provide insight into carbon dynamics in North America. In particular, we analyze hourly CO2 mixing ratio data from a sparse network of eight towers in North America for 2004. A prior estimate of carbon fluxes due to Gross Primary Productivity (GPP and Ecosystem Respiration (ER is constructed from the SiB3 biosphere model on a 40 km grid. A combination of transport from the RAMS and the Parameterized Chemical Transport Model (PCTM models is used to forge a connection between upwind biosphere fluxes and downwind observed CO2 mixing ratio data. A Kalman filter procedure is used to estimate weekly corrections to biosphere fluxes based upon observed CO2. RMSE-weighted annual NEE estimates, over an ensemble of potential inversion parameter sets, show a

  7. Summer precipitation anomalies in Asia and North America induced by Eurasian non-monsoon land heating versus ENSO

    Science.gov (United States)

    Zhao, Ping; Wang, Bin; Liu, Jiping; Zhou, Xiuji; Chen, Junming; Nan, Sulan; Liu, Ge; Xiao, Dong

    2016-02-01

    When floods ravage Asian monsoon regions in summer, megadroughts often attack extratropical North America, which feature an intercontinental contrasting precipitation anomaly between Asia and North America. However, the characteristics of the contrasting Asian-North American (CANA) precipitation anomalies and associated mechanisms have not been investigated specifically. In this article, we firmly establish this summer CANA pattern, providing evidence for a significant effect of the land surface thermal forcing over Eurasian non-monsoon regions on the CANA precipitation anomalies by observations and numerical experiments. We show that the origin of the CANA precipitation anomalies and associated anomalous anticyclones over the subtropical North Pacific and Atlantic has a deeper root in Eurasian non-monsoon land surface heating than in North American land surface heating. The ocean forcing from the ENSO is secondary and tends to be confined in the tropics. Our results have strong implications to interpretation of the feedback of global warming on hydrological cycle over Asia and North America. Under the projected global warming due to the anthropogenic forcing, the prominent surface warming over Eurasian non-monsoon regions is a robust feature which, through the mechanism discussed here, would favor a precipitation increase over Asian monsoon regions and a precipitation decrease over extratropical North America.

  8. Summer precipitation anomalies in Asia and North America induced by Eurasian non-monsoon land heating versus ENSO.

    Science.gov (United States)

    Zhao, Ping; Wang, Bin; Liu, Jiping; Zhou, Xiuji; Chen, Junming; Nan, Sulan; Liu, Ge; Xiao, Dong

    2016-01-01

    When floods ravage Asian monsoon regions in summer, megadroughts often attack extratropical North America, which feature an intercontinental contrasting precipitation anomaly between Asia and North America. However, the characteristics of the contrasting Asian-North American (CANA) precipitation anomalies and associated mechanisms have not been investigated specifically. In this article, we firmly establish this summer CANA pattern, providing evidence for a significant effect of the land surface thermal forcing over Eurasian non-monsoon regions on the CANA precipitation anomalies by observations and numerical experiments. We show that the origin of the CANA precipitation anomalies and associated anomalous anticyclones over the subtropical North Pacific and Atlantic has a deeper root in Eurasian non-monsoon land surface heating than in North American land surface heating. The ocean forcing from the ENSO is secondary and tends to be confined in the tropics. Our results have strong implications to interpretation of the feedback of global warming on hydrological cycle over Asia and North America. Under the projected global warming due to the anthropogenic forcing, the prominent surface warming over Eurasian non-monsoon regions is a robust feature which, through the mechanism discussed here, would favor a precipitation increase over Asian monsoon regions and a precipitation decrease over extratropical North America. PMID:26916258

  9. Cryptococcus gattii: An Emerging Cause of Fungal Disease in North America

    Directory of Open Access Journals (Sweden)

    Ashwin Dixit

    2009-01-01

    Full Text Available During the latter half of the twentieth century, fungal pathogens such as Cryptococcus neoformans were increasingly recognized as a significant threat to the health of immune compromised populations throughout the world. Until recently, the closely related species C. gattii was considered to be a low-level endemic pathogen that was confined to tropical regions such as Australia. Since 1999, C. gattii has emerged in the Pacific Northwest region of North America and has been responsible for a large disease epidemic among generally healthy individuals. The changing epidemiology of C. gattii infection is likely to be a consequence of alterations in fungal ecology and biology and illustrates its potential to cause serious human disease. This review summarizes selected biological and clinical aspects of C. gattii that are particularly relevant to the recent North American outbreak and compares these to the Australian and South American experience.

  10. Normalization references for Europe and North America for application with USEtox™ characterization factors

    DEFF Research Database (Denmark)

    Laurent, Alexis; Lautier, Anne; Rosenbaum, Ralph K.;

    2011-01-01

    Purpose: In life cycle impact assessment, normalization can be a very effective tool for the life cycle assessment practitioner to interpret results and put them into perspective. The paper presents normalization references for the recently developed USEtox™ model, which aims at calculating...... globally applicable characterization factors. Normalization references for Europe and North America are determined, and guidance for expansions to other geographical regions is provided. Materials and methods The base years of the European and North American inventories are 2004 and 2002/2008, respectively......, a similar coverage of substances was obtained for both regions with relatively high representation of metals and a number of organic compounds, mainly consisting of non-methane volatile organic compounds and pesticides. The two inventory sets were eventually characterized with the characterization factors...

  11. Dynamical and thermodynamical modulations of future changes in landfalling atmospheric rivers over North America

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yang; Lu, Jian; Leung, Lai-Yung R.; Yang, Qing; Hagos, Samson M.; Qian, Yun

    2015-09-12

    This study examines the changes of landfalling atmospheric rivers (ARs) over the west coast of North America in response to future warming using model outputs from the Coupled Model Intercomparison Project phase 5 (CMIP5). The result reveals a strikingly large magnitude of increase of AR days by the end of the 21st century in the RCP8.5 climate change scenario, with fractional increases ranging between ~50% and 600%, depending on the seasons and the landfall locations. These increases are predominantly controlled by the super-Clausius-Clapeyron rate of increase of atmospheric water vapor with warming, while changes of winds that transport moisture in the ARs, or dynamical effect, mostly counter the thermodynamical effect of increasing water vapor, limiting the increase of AR events in the future. The consistent negative effect of wind changes on AR days during spring and fall can be further linked to the robust poleward shift of the subtropical jet in the North Pacific basin.

  12. Molecular identification of sand flies (Diptera: Psychodidae) in eastern North America by using PCR-RFLP.

    Science.gov (United States)

    Minter, Logan M; Yu, Tian; Florin, David A; Nukmal, Nismah; Brown, Grayson C; Zhou, Xuguo

    2013-07-01

    Sand flies (Diptera: Psychodidae) are small blood-feeding dipterans that are primary vectors of numerous human and livestock pathogens. Effective surveillance programs with accurate identification tools are critical in development and implementation of modern integrated pest management programs. Although morphological keys are available for North American species, identification can still be challenging owing to the nature of sample preparation and incompatibility with molecular or biochemical-based pathology assays. Further, the potential for introduction of Old World or other exotic species is not accounted for by current keys. Herein, we present the development and validation of a restriction fragment-length polymorphism-based molecular identification method. Specifically, cytochrome c oxidase subunit I, a mitochondrial DNA marker, was used to distinguish two species of adult sand flies indigenous to eastern North America with two exotic species not yet known to occur in the United States.

  13. A continental scale model for dissolved silica mobilization in North America

    Science.gov (United States)

    Jansen, N.; Lauerwald, R.; Hartmann, J.; Dürr, H. H.; Loos, S.; Kempe, S.; Middelkoop, H.

    2009-04-01

    flux (Bluth and Kump, 1994; Hartmann et al., 2009). Only in relation to some lithological classes, temperature and terrain slope constitute significant predictors. An influence of land cover, soil properties or other predictors is not observed. This is partly attributed to geodata resolution and classification. Lithological classes "Basic Volcanics and Pyroclastics" and "Basic and Intermediate Plutonics" show the highest DSi yields, with respect to a given discharge. The lithological class "Siliciclastic Sedimentary Rocks" is characterized by the lowest DSi yield. The model explains 89% of the DSi yield variance; the average yield of catchments employed in model calibration is 4.32 t SiO2 km-2a-1, somewhat above the global average yield of 3.3 t SiO2 km-2a-1 (Dürr et al., 2009). The model quantifies DSi fluxes from the terrestrial into the continental aquatic systems. This helps to estimate DSi retention within fluvial systems (Lauerwald et al., submitted) and improves understanding of this part of the silicon cycle. References: Bluth, G.J.S., and Kump, L.R., 1994, Lithologic and Climatologic Controls of River Chemistry: Geochimica Cosmochimica Acta, 58, 2341-2359. Dürr, H.H., Meybeck, M., Hartmann, J., Laruelle, G.G., and Roubeix, V., 2009, Global Spatial distribution of natural riverine silica inputs to the coastal zone: Biogeosciences, (in review), bgd-2008-0173. Hartmann, J., Jansen, N., Dürr, H.H., Harashima, A., Okubo, K., and Kempe, S., 2009, Predicting riverine dissolved silica fluxes into coastal zones from a hyperactive region and analysis of their first order controls: International Journal of Earth Sciences, (DOI 10.1007/s00531-008-0381-5). Lauerwald, R., Jansen N., Hartmann, J., Dürr, H.H., Loos, S., Kempe, S., Middelkoop, H., submitted, Modeling dissolved silica retention in the limnic system of North America. (Submitted to this session).

  14. Late Paleozoic deformation of interior North America: The greater Ancestral Rocky Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Hongzhuan [Massachusetts Inst. of Technology, Cambridge, MA (United States)]|[Univ. of Texas at Dallas, Richardson, TX (United States); Royden, L.; Burchfiel, C. [Massachusetts Inst. of Technology, Cambridge, MA (United States); Schuepbach, M. [MAXUS Energy Co., Dallas, TX (United States)

    1996-09-01

    Late Paleozoic deformation within interior North America has produced a series of north-northwest- to northwest-trending elongate basins that cover much of Oklahoma, Texas, New Mexico, Colorado, and Utah. Each basin thickens asymmetrically toward an adjacent region of coeval basement uplift from which it is separated by synsedimentary faults with great vertical relief. The remarkable coincidence in timing, geometry, and apparent structural style throughout the region of late Paleozoic deformation strongly suggests that these paired regions of basin subsidence and basement uplift form a unified system of regional deformation, the greater Ancestral Rocky Mountains. Over this region, basin subsidence and basement uplift were approximately synchronous, beginning in the Chesterian-Morrowan, continuing through the Pennsylvanian, and ending in the Wolfcampian (although minor post-Wolfcampian deformation occurs locally). The basement uplifts show evidence for folding and faulting in the Pennsylvanian and Early Permian. Reverse faults and thrust faults have been drilled over many of the uplifts, but only in the Anadarko region has thrusting of the basement uplifts over the adjacent basin been clearly documented. Extensive basement-involved thrusting also occurs along the margins of the Delaware and Midland basins, and suggests that the entire greater Ancestral Rocky Mountains region probably formed as the result of northeast-southwest-directed-intraplate shortening. Deformation within the greater Ancestral Rocky Mountains was coeval with late Paleozoic subduction along much of the North American plate margin, and has traditionally been related to emplacement of thrust sheets within the Ouachita-Marathon orogenic belt. The nature, timing, and orientation of events along the Ouachita-Marathon belt make it difficult to drive the deformation of the greater Ancestral Rocky Mountains by emplacement of the Ouachita-Marathon belt along the southern margin of North America.

  15. Genetic structure of avian influenza viruses from ducks of the Atlantic flyway of North America.

    Directory of Open Access Journals (Sweden)

    Yanyan Huang

    Full Text Available Wild birds, including waterfowl such as ducks, are reservoir hosts of influenza A viruses. Despite the increased number of avian influenza virus (AIV genome sequences available, our understanding of AIV genetic structure and transmission through space and time in waterfowl in North America is still limited. In particular, AIVs in ducks of the Atlantic flyway of North America have not been thoroughly investigated. To begin to address this gap, we analyzed 109 AIV genome sequences from ducks in the Atlantic flyway to determine their genetic structure and to document the extent of gene flow in the context of sequences from other locations and other avian and mammalian host groups. The analyses included 25 AIVs from ducks from Newfoundland, Canada, from 2008-2011 and 84 available reference duck AIVs from the Atlantic flyway from 2006-2011. A vast diversity of viral genes and genomes was identified in the 109 viruses. The genetic structure differed amongst the 8 viral segments with predominant single lineages found for the PB2, PB1 and M segments, increased diversity found for the PA, NP and NS segments (2, 3 and 3 lineages, respectively, and the highest diversity found for the HA and NA segments (12 and 9 lineages, respectively. Identification of inter-hemispheric transmissions was rare with only 2% of the genes of Eurasian origin. Virus transmission between ducks and other bird groups was investigated, with 57.3% of the genes having highly similar (≥99% nucleotide identity genes detected in birds other than ducks. Transmission between North American flyways has been frequent and 75.8% of the genes were highly similar to genes found in other North American flyways. However, the duck AIV genes did display spatial distribution bias, which was demonstrated by the different population sizes of specific viral genes in one or two neighbouring flyways compared to more distant flyways.

  16. A new troodontid theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous Western Interior Basin of North America.

    Directory of Open Access Journals (Sweden)

    Lindsay E Zanno

    Full Text Available BACKGROUND: Troodontids are a predominantly small-bodied group of feathered theropod dinosaurs notable for their close evolutionary relationship with Avialae. Despite a diverse Asian representation with remarkable growth in recent years, the North American record of the clade remains poor, with only one controversial species--Troodon formosus--presently known from substantial skeletal remains. METHODOLOGY/PRINCIPAL FINDINGS: Here we report a gracile new troodontid theropod--Talos sampsoni gen. et sp. nov.--from the Upper Cretaceous Kaiparowits Formation, Utah, USA, representing one of the most complete troodontid skeletons described from North America to date. Histological assessment of the holotype specimen indicates that the adult body size of Talos was notably smaller than that of the contemporary genus Troodon. Phylogenetic analysis recovers Talos as a member of a derived, latest Cretaceous subclade, minimally containing Troodon, Saurornithoides, and Zanabazar. MicroCT scans reveal extreme pathological remodeling on pedal phalanx II-1 of the holotype specimen likely resulting from physical trauma and subsequent infectious processes. CONCLUSION/SIGNIFICANCE: Talos sampsoni adds to the singularity of the Kaiparowits Formation dinosaur fauna, which is represented by at least 10 previously unrecognized species including the recently named ceratopsids Utahceratops and Kosmoceratops, the hadrosaurine Gryposaurus monumentensis, the tyrannosaurid Teratophoneus, and the oviraptorosaurian Hagryphus. The presence of a distinct troodontid taxon in the Kaiparowits Formation supports the hypothesis that late Campanian dinosaurs of the Western Interior Basin exhibited restricted geographic ranges and suggests that the taxonomic diversity of Late Cretaceous troodontids from North America is currently underestimated. An apparent traumatic injury to the foot of Talos with evidence of subsequent healing sheds new light on the paleobiology of deinonychosaurians

  17. Wing Color of Monarch Butterflies (Danaus plexippus) in Eastern North America across Life Stages: Migrants Are “Redder” than Breeding and Overwintering Stages

    OpenAIRE

    Davis, Andrew K.

    2009-01-01

    Monarch butterflies are famous among insects for their unique migration in eastern North America to overwinter sites in Mexico and their bright orange wing color, which has an aposematic function. While capturing migrating monarchs in northeast Georgia, USA, I noticed that many appeared to have unusually deep orange wings. I initiated the current study to compare wing hues (obtained using image analysis of scanned wings) of migrants (captured in 2005 and 2008) to samples of breeding and over...

  18. Herbarium specimens reveal the footprint of climate change on flowering trends across north-central North America.

    Science.gov (United States)

    Calinger, Kellen M; Queenborough, Simon; Curtis, Peter S

    2013-08-01

    Shifting flowering phenology with rising temperatures is occurring worldwide, but the rarity of co-occurring long-term observational and temperature records has hindered the evaluation of phenological responsiveness in many species and across large spatial scales. We used herbarium specimens combined with historic temperature data to examine the impact of climate change on flowering trends in 141 species collected across 116,000 km(2) in north-central North America. On average, date of maximum flowering advanced 2.4 days °C(-1), although species-specific responses varied from - 13.5 to + 7.3 days °C(-1). Plant functional types exhibited distinct patterns of phenological responsiveness with significant differences between native and introduced species, among flowering seasons, and between wind- and biotically pollinated species. This study is the first to assess large-scale patterns of phenological responsiveness with broad species representation and is an important step towards understanding current and future impacts of climate change on species performance and biodiversity. PMID:23786499

  19. An exploration of common reed (Phragmites australis bioenergy potential in North America

    Directory of Open Access Journals (Sweden)

    R. Vaičekonytė

    2014-10-01

    Full Text Available In North America, reed (Phragmites australis is typically considered to be a weed although it provides important ecosystem services. Small, sparse, patchy or mixed reedbeds are more suitable as habitat for many species than extensive dense reedbeds, whose habitat functions can be enhanced by the selective removal of biomass. We propose that above-ground reed biomass could be harvested for bioenergy, at the same time improving habitat for biodiversity by thinning or fragmenting the more extensive reedbeds. Biofuel pellets manufactured from reeds harvested at Montréal (Canada had moisture content 6.4 %, energy content 16.9 kJ g-1 (dry mass, ash content 3.44 %, and chloride content 1962 ppm. Thus, reed as a material for fuel pellet manufacture is similar to switchgrass (Panicum virgatum, which is commonly cultivated for that purpose and requires higher inputs than harvested wild reed. We discuss these findings in the context of environmental considerations and conclude that the bioenergy potential of reed could most expediently be realised in North America by combining material harvested from the widespread spontaneously occurring reedbeds with organic waste from other sources to create mixed biofuels. However, reeds with high levels of chlorine, sulphur or metals should not be burned to avoid air pollution or equipment damage unless these problems are mitigated by means of appropriate season of harvest, equipment, combustion regime, or use of a mixed feedstock.

  20. The Northern Path of Asian Dust Transport from the Gobi Desert to North America

    Institute of Scientific and Technical Information of China (English)

    CHEN Ke-Yi

    2010-01-01

    The aerosol index(AI)of the Total Ozone Mapping Spectrometer(TOMS)satellite data(1979-2001)was analyzed to reveal the climatological long-distance path of dust transport from Asia to North America.The AI in the west coast of the United States is highly correlated with that in the Gobi desert.Additionally,from the TOMS satellite images,it can be seen that very strong plumes advect from Asia to the west coast of North America in typical dust storm cases.When applying the sourcereceptor relationship to detect the northern dust transport path between the Gobi source region and the west coast of the United States receptor region,it is evident that the dust plume can be transported northward beyond 60°N from its source region and that it takes 5 to 6 days to reach the west coast of the United States.The cross correlation technique shown in this work is a useful tool that can be applied in other regions to give useful insights into relationships between major dust sources and downwind receptor locations by using remotely sensed dust observations.

  1. Sunflower domestication alleles support single domestication center in eastern North America.

    Science.gov (United States)

    Blackman, Benjamin K; Scascitelli, Moira; Kane, Nolan C; Luton, Harry H; Rasmussen, David A; Bye, Robert A; Lentz, David L; Rieseberg, Loren H

    2011-08-23

    Phylogenetic analyses of genes with demonstrated involvement in evolutionary transitions can be an important means of resolving conflicting hypotheses about evolutionary history or process. In sunflower, two genes have previously been shown to have experienced selective sweeps during its early domestication. In the present study, we identified a third candidate early domestication gene and conducted haplotype analyses of all three genes to address a recent, controversial hypothesis about the origin of cultivated sunflower. Although the scientific consensus had long been that sunflower was domesticated once in eastern North America, the discovery of pre-Columbian sunflower remains at archaeological sites in Mexico led to the proposal of a second domestication center in southern Mexico. Previous molecular studies with neutral markers were consistent with the former hypothesis. However, only two indigenous Mexican cultivars were included in these studies, and their provenance and genetic purity have been questioned. Therefore, we sequenced regions of the three candidate domestication genes containing SNPs diagnostic for domestication from large, newly collected samples of Mexican sunflower landraces and Mexican wild populations from a broad geographic range. The new germplasm also was genotyped for 12 microsatellite loci. Our evidence from multiple evolutionarily important loci and from neutral markers supports a single domestication event for extant cultivated sunflower in eastern North America.

  2. Post-Clovis survival of American Mastodon in the southern Great Lakes Region of North America

    Science.gov (United States)

    Woodman, Neal; Beavan Athfield, Nancy

    2009-11-01

    The end of the Pleistocene in North America was marked by a wave of extinctions of large mammals, with the last known appearances of many species falling between ca. 11,000-10,000 14C yr BP. Temporally, this period overlaps with the Clovis Paleoindian cultural complex (11,190-10,530 14C yr BP) and with sudden climatic changes that define the beginning of the Younger Dryas chronozone (ca. 11,000-10,000 14C yr BP), both of which have been considered as potential proximal causes of this extinction event. Radiocarbon dating of enamel and filtered bone collagen from an extinct American Mastodon ( Mammut americanum) from northern Indiana, USA, by accelerator mass spectrometer yielded direct dates of 10,055 ± 40 14C yr BP and 10,032 ± 40 14C yr BP, indicating that the animal survived beyond the Clovis time period and into the late Younger Dryas. Although the late survival of this species in mid-continental North America does not remove either humans or climatic change as contributing causes for the late Pleistocene extinctions, neither Clovis hunters nor the climatic perturbations initiating the Younger Dryas chronozone were immediately responsible for driving mastodons to extinction.

  3. Warming shifts `worming': effects of experimental warming on invasive earthworms in northern North America

    Science.gov (United States)

    Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A.; Rice, Karen; Rich, Roy; Reich, Peter B.

    2014-11-01

    Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration.

  4. Hydrologic effects of land and water management in North America and Asia: 1700–1992

    Directory of Open Access Journals (Sweden)

    I. Haddeland

    2006-09-01

    Full Text Available The hydrologic effects of land use changes, dams, and irrigation in North America and Asia over the past 300 years are studied using a macroscale hydrologic model. The simulation results indicate that the expansion of croplands over the last three centuries has resulted in 2.5 and 6 percent increases in annual runoff volumes for North America and Asia, respectively, and that these increases in runoff to some extent have been compensated by increased evapotranspiration caused by irrigation practices. Averaged over the year and the continental scale, the accumulated anthropogenic impacts on surface water fluxes are hence relatively minor. However, for some regions within the continents human activities have altered hydrologic regimes profoundly. Reservoir operations and irrigation practices in the western part of USA and Mexico have resulted in a 25 percent decrease in streamflow in June, and a 9 percent decrease in annual runoff volumes reaching the Pacific Ocean. In the area in South East Asia draining to the Pacific Ocean, land use changes have caused an increase in runoff volumes throughout the year, and the average annual increase in runoff is 12 percent.

  5. Constraints from observations and modeling on atmosphere–surface exchange of mercury in eastern North America

    Directory of Open Access Journals (Sweden)

    Shaojie Song

    2016-04-01

    Full Text Available Abstract Atmosphere–surface exchange of mercury, although a critical component of its global cycle, is currently poorly constrained. Here we use the GEOS-Chem chemical transport model to interpret atmospheric Hg0 (gaseous elemental mercury data collected during the 2013 summer Nitrogen, Oxidants, Mercury and Aerosol Distributions, Sources and Sinks (NOMADSS aircraft campaign as well as ground- and ship-based observations in terms of their constraints on the atmosphere–surface exchange of Hg0 over eastern North America. Model–observation comparison suggests that the Northwest Atlantic may be a net source of Hg0, with high evasion fluxes in summer (our best sensitivity simulation shows an average oceanic Hg0 flux of 3.3 ng m-2 h-1 over the Northwest Atlantic, while the terrestrial ecosystem in the summer of the eastern United States is likely a net sink of Hg0 (our best sensitivity simulation shows an average terrestrial Hg0 flux of -0.6 ng m-2 h-1 over the eastern United States. The inferred high Hg0 fluxes from the Northwest Atlantic may result from high wet deposition fluxes of oxidized Hg, which are in turn related to high precipitation rates in this region. We also find that increasing simulated terrestrial fluxes of Hg0 in spring compared to other seasons can better reproduce observed seasonal variability of Hg0 concentration at ground-based sites in eastern North America.

  6. Tracking multi-generational colonization of the breeding grounds by monarch butterflies in eastern North America.

    Science.gov (United States)

    Flockhart, D T Tyler; Wassenaar, Leonard I; Martin, Tara G; Hobson, Keith A; Wunder, Michael B; Norris, D Ryan

    2013-10-01

    Insect migration may involve movements over multiple breeding generations at continental scales, resulting in formidable challenges to their conservation and management. Using distribution models generated from citizen scientist occurrence data and stable-carbon and -hydrogen isotope measurements, we tracked multi-generational colonization of the breeding grounds of monarch butterflies (Danaus plexippus) in eastern North America. We found that monarch breeding occurrence was best modelled with geographical and climatic variables resulting in an annual breeding distribution of greater than 12 million km(2) that encompassed 99% occurrence probability. Combining occurrence models with stable isotope measurements to estimate natal origin, we show that butterflies which overwintered in Mexico came from a wide breeding distribution, including southern portions of the range. There was a clear northward progression of monarchs over successive generations from May until August when reproductive butterflies began to change direction and moved south. Fifth-generation individuals breeding in Texas in the late summer/autumn tended to originate from northern breeding areas rather than regions further south. Although the Midwest was the most productive area during the breeding season, monarchs that re-colonized the Midwest were produced largely in Texas, suggesting that conserving breeding habitat in the Midwest alone is insufficient to ensure long-term persistence of the monarch butterfly population in eastern North America. PMID:23926146

  7. Red brome (Bromus rubens subsp. madritensis) in North America: Possible modes for early introductions, subsequent spread

    Science.gov (United States)

    Salo, L.F.

    2005-01-01

    Although invasions by exotic plants have increased dramatically as human travel and commerce have increased, few have been comprehensively described. Understanding the patterns of invasive species spread over space and time will help guide management activities and policy. Tracing the earliest appearances of an exotic plant reveals likely sites of introduction, paving the way for genetic studies to quantify founder events and identify potential source populations. Red brome (Bromus madritensis subsp. rubens) is a Mediterranean winter annual grass that has invaded even relatively undisturbed areas of western North America, where it threatens native plant communities. This study used herbarium records and contemporary published accounts to trace the early introductions and subsequent spread of red brome in western North America. The results challenge the most frequently cited sources describing the early history of this grass and suggest three possible modes for early introductions: the California Gold Rush and Central Valley wheat, southern California shipping, and northern California sheep. Subsequent periods of most rapid spread into new areas, from 1930 to 1942, and of greatest spread into new regions, during the past 50 years, coincide with warm Pacific Decadal Oscillation regimes, which are linked to increased winter precipitation in the southwestern USA and northern Mexico. Global environmental change, including increased atmospheric CO2 levels and N deposition, may be contributing to the success of red brome, relative to native species.

  8. Biomass enables the transition to a carbon-negative power system across western North America

    Science.gov (United States)

    Sanchez, Daniel L.; Nelson, James H.; Johnston, Josiah; Mileva, Ana; Kammen, Daniel M.

    2015-03-01

    Sustainable biomass can play a transformative role in the transition to a decarbonized economy, with potential applications in electricity, heat, chemicals and transportation fuels. Deploying bioenergy with carbon capture and sequestration (BECCS) results in a net reduction in atmospheric carbon. BECCS may be one of the few cost-effective carbon-negative opportunities available should anthropogenic climate change be worse than anticipated or emissions reductions in other sectors prove particularly difficult. Previous work, primarily using integrated assessment models, has identified the critical role of BECCS in long-term (pre- or post-2100 time frames) climate change mitigation, but has not investigated the role of BECCS in power systems in detail, or in aggressive time frames, even though commercial-scale facilities are starting to be deployed in the transportation sector. Here, we explore the economic and deployment implications for BECCS in the electricity system of western North America under aggressive (pre-2050) time frames and carbon emissions limitations, with rich technology representation and physical constraints. We show that BECCS, combined with aggressive renewable deployment and fossil-fuel emission reductions, can enable a carbon-negative power system in western North America by 2050 with up to 145% emissions reduction from 1990 levels. In most scenarios, the offsets produced by BECCS are found to be more valuable to the power system than the electricity it provides. Advanced biomass power generation employs similar system design to advanced coal technology, enabling a transition strategy to low-carbon energy.

  9. The Contribution of Soils to North America's Current and Future Climate

    Science.gov (United States)

    Mayes, M. A.; Reed, S.; Thornton, P. E.; Lajtha, K.; Bailey, V. L.; Shrestha, G.; Jastrow, J. D.; Torn, M. S.

    2015-12-01

    This presentation will cover key aspects of the terrestrial soil carbon cycle in North America and the US for the upcoming State of the Carbon Cycle Report (SOCCRII). SOCCRII seeks to summarize how natural processes and human interactions affect the global carbon cycle, how socio-economic trends affect greenhouse gas concentrations in the atmosphere, and how ecosystems are influenced by and respond to greenhouse gas emissions, management decisions, and concomitant climate effects. Here, we will summarize the contemporary understanding of carbon stocks, fluxes, and drivers in the soil ecosystem compartment. We will highlight recent advances in modeling the magnitude of soil carbon stocks and fluxes, as well as the importance of remaining uncertainties in predicting soil carbon cycling and its relationship with climate. Attention will be given to the role of uncertainties in predicting future fluxes from soils, and how those uncertainties vary by region and ecosystem. We will also address how climate feedbacks and management decisions can enhance or minimize future climatic effects based on current understanding and observations, and will highlight select research needs to improve our understanding of the balance of carbon in soils in North America.

  10. Infectious disease in cervids of North America: data, models, and management challenges.

    Science.gov (United States)

    Conner, Mary Margaret; Ebinger, Michael Ryan; Blanchong, Julie Anne; Cross, Paul Chafee

    2008-01-01

    Over the past two decades there has been a steady increase in the study and management of wildlife diseases. This trend has been driven by the perception of an increase in emerging zoonotic diseases and the recognition that wildlife can be a critical factor for controlling infectious diseases in domestic animals. Cervids are of recent concern because, as a group, they present a number of unique challenges. Their close ecological and phylogenetic relationship to livestock species places them at risk for receiving infections from, and reinfecting livestock. In addition, cervids are an important resource; revenue from hunting and viewing contribute substantially to agency budgets and local economies. A comprehensive coverage of infectious diseases in cervids is well beyond the scope of this chapter. In North America alone there are a number of infectious diseases that can potentially impact cervid populations, but for most of these, management is not feasible or the diseases are only a potential or future concern. We focus this chapter on three diseases that are of major management concern and the center of most disease research for cervids in North America: bovine tuberculosis, chronic wasting disease, and brucellosis. We discuss the available data and recent advances in modeling and management of these diseases.

  11. Post-Clovis survival of American Mastodon in the southern Great Lakes Region of North America

    Science.gov (United States)

    Woodman, N.; Beavan, Athfield N.

    2009-01-01

    The end of the Pleistocene in North America was marked by a wave of extinctions of large mammals, with the last known appearances of many species falling between ca. 11,000-10,000??14C yr BP. Temporally, this period overlaps with the Clovis Paleoindian cultural complex (11,190-10,530??14C yr BP) and with sudden climatic changes that define the beginning of the Younger Dryas chronozone (ca. 11,000-10,000??14C yr BP), both of which have been considered as potential proximal causes of this extinction event. Radiocarbon dating of enamel and filtered bone collagen from an extinct American Mastodon (Mammut americanum) from northern Indiana, USA, by accelerator mass spectrometer yielded direct dates of 10,055 ?? 40??14C yr BP and 10,032 ?? 40??14C yr BP, indicating that the animal survived beyond the Clovis time period and into the late Younger Dryas. Although the late survival of this species in mid-continental North America does not remove either humans or climatic change as contributing causes for the late Pleistocene extinctions, neither Clovis hunters nor the climatic perturbations initiating the Younger Dryas chronozone were immediately responsible for driving mastodons to extinction. ?? 2009 University of Washington.

  12. Infectious disease in cervids of North America: data, models, and management challenges.

    Science.gov (United States)

    Conner, Mary Margaret; Ebinger, Michael Ryan; Blanchong, Julie Anne; Cross, Paul Chafee

    2008-01-01

    Over the past two decades there has been a steady increase in the study and management of wildlife diseases. This trend has been driven by the perception of an increase in emerging zoonotic diseases and the recognition that wildlife can be a critical factor for controlling infectious diseases in domestic animals. Cervids are of recent concern because, as a group, they present a number of unique challenges. Their close ecological and phylogenetic relationship to livestock species places them at risk for receiving infections from, and reinfecting livestock. In addition, cervids are an important resource; revenue from hunting and viewing contribute substantially to agency budgets and local economies. A comprehensive coverage of infectious diseases in cervids is well beyond the scope of this chapter. In North America alone there are a number of infectious diseases that can potentially impact cervid populations, but for most of these, management is not feasible or the diseases are only a potential or future concern. We focus this chapter on three diseases that are of major management concern and the center of most disease research for cervids in North America: bovine tuberculosis, chronic wasting disease, and brucellosis. We discuss the available data and recent advances in modeling and management of these diseases. PMID:18566093

  13. Multifactor controls on terrestrial N2O flux over North America from 1979 through 2010

    Directory of Open Access Journals (Sweden)

    C. Q. Lu

    2012-04-01

    Full Text Available Nitrous oxide (N2O is a potent greenhouse gas which also contributes to the depletion of stratospheric ozone (O3. However, the magnitude and underlying mechanisms for the spatiotemporal variations in the terrestrial sources of N2O are still far from certain. Using a process-based ecosystem model (DLEM – the Dynamic Land Ecosystem Model driven by multiple global change factors, including climate variability, nitrogen (N deposition, rising atmospheric carbon dioxide (CO2, tropospheric O3 pollution, N fertilizer application, and land conversion, this study examined the spatial and temporal variations in terrestrial N2O flux over North America and further attributed these variations to various driving factors. From 1979 to 2010, the North America cumulatively emitted 53.9 ± 0.9 Tg N2O-N (1 Tg = 1012 g, of which global change factors contributed 2.4 ± 0.9 Tg N2O-N, and baseline emission contributed 51.5 ± 0.6 Tg N2O-N. Climate variability, N deposition, O3 pollution, N fertilizer application, and land conversion increased N2O emission while the elevated atmospheric CO2 posed opposite effect at continental level; the interactive effect among multiple factors enhanced N2O emission over the past 32 yr. N input, including N fertilizer application in cropland and N deposition, and multi-factor interaction dominated the increases in N2O emission at continental level. At country level, N fertilizer application and multi-factor interaction made large contribution to N2O emission increase in the United States of America (USA. The climate variability dominated the increase in N2O emission from Canada. N inputs and multiple factors interaction made large contribution to the increases in N2O emission from Mexico. Central and southeastern parts of the North America – including central Canada, central USA, southeastern USA, and all of Mexico – experienced increases in N2O emission from 1979 to 2010. The fact that climate variability and multi

  14. Identifying important breast cancer control strategies in Asia, Latin America and the Middle East/North Africa

    Directory of Open Access Journals (Sweden)

    Niessen Louis W

    2011-09-01

    Full Text Available Abstract Background Breast cancer is the most frequent cause of cancer death in women worldwide, but global disparities in breast cancer control persist, due to a lack of a comprehensive breast cancer control strategy in many countries. Objectives To identify and compare the need for breast cancer control strategies in Asia, Latin America and the Middle East/North Africa and to develop a common framework to guide the development of national breast cancer control strategies. Methods Data were derived from open-ended, semi-structured interviews conducted in 2007 with 221 clinicians, policy makers, and patient advocates; stratified across Asia (n = 97, Latin America (n = 46, the Middle East/North Africa (ME/NA (n = 39 and Australia and Canada (n = 39. Respondents were identified using purposive and snowballing sampling. Interpretation of the data utilized interpretive phenomenological analysis where transcripts and field notes were coded and analyzed and common themes were identified. Analysis of regional variation was conducted based on the frequency of discussion and the writing of the manuscript followed the RATS guidelines. Results Analysis revealed four major themes that form the foundation for developing national breast cancer control strategies: 1 building capacity; 2 developing evidence; 3 removing barriers; and 4 promoting advocacy - each specified across five sub-ordinate dimensions. The propensity to discuss most dimensions was similar across regions, but managing advocacy was discussed more frequently (p = 0.004 and organized advocacy was discussed less frequently (p Conclusions This unique research identified common themes for the development of breast cancer control strategies, grounded in the experience of local practitioners, policy makers and advocacy leaders across diverse regions. Future research should be aimed at gathering a wider array of experiences, including those of patients.

  15. Large-scale hydrological changes in North America and Scandinavia from GRACE

    Science.gov (United States)

    Steffen, Holger; Wang, Hansheng; Jia, Lulu; Wu, Patrick; Jiang, Liming; Hsu, Houtse; Xiang, Longwei; Wang, Zhiyong; Hu, Bo

    2013-04-01

    The Gravity Recovery and Climate Experiment (GRACE) satellite mission has proven to be an invaluable tool in monitoring hydrological changes. Due to the fact that GRACE detects combined mass changes from different sources, dedicated hydrological studies, however, have been mainly limited to areas where the GRACE signal is assumed to be solely related to hydrology or where other overlapping processes can be removed as accurately as possible. In North America and northern Europe, the dominating glacial isostatic adjustment (GIA) signal is shadowing water storage changes. Here, modeled GIA data are used for removal, but model imperfections contaminate the hydrology signal. With a new separation approach we are able to self-determine the hydrological contribution in North America and northern Europe from GRACE and GPS data (Wang et al., 2012). The separation of the hydrological signal is not GIA model dependent and thus provides a clear picture of water storage changes in those areas free of the usually large remnant GIA contributions. From August 2002 to March 2011, the derived mass increase in central North America is about 43.0±5.0 Gt/yr. This is about three quarter of all water falling down Niagara Falls every year. Average groundwater variations from wells in Alberta and central Saskatchewan are in very good agreement to our result and show a significant increase from the year 2002 on. Before that year, there is a significant drop in water levels beginning in 1999/2000, which is related to a drought in the Canadian Prairies during these years. The increase from about 2003 on can be interpreted as the recovery of the water storage after the drought. As the GRACE observation period begins during that time, GRACE exactly observes this recovery in form of a significant mass increase. Changes in water levels from tide gauges for the Great Lakes and groundwater wells in the Lower Peninsula of Michigan also agree to our findings. At the southern tip of the Scandinavian

  16. Campanian Climatic Change: Isotopic Evidence from Far East, North America, North Atlantic and Western Europe

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Paleoclimatic settings have been reconstructed for the Campanian using original oxygenisotopic analyses of well-preserved molluskan and foraminifera shells from Russian Far East,Hokkaido, USA, Belgium and some DSDP holes (95, 98, 102, 390A, and 392A) in North Atlantic. Early Early Campanian climatic optimum has been recognized from data on high bottom shelf water paleotemperatures in middle latitudes of both the western circum-Pacific (to 24.2℃) and the eastern circum-Pacific (to 26.4℃) areas and high bottom shallow water paleotemperatures in high latitudes of the Koryak Upland (22.4-25.5℃), which agrees with the data on the Campanian Barykovskaya flora in high latitudes (Golovneva and Herman, 1998) and Jonker flora and its equivalents in middle latitudes. Judging from the data on comparatively high bottom shallow water paleotemperature values in high latitudes, South Alaska (19.4℃) and the Koryak Upland (22.4-25.5℃), we also expect Latest Campanian temperature maximum, which has not been confirmed, however, for low and middle latitudes by neither of isotopic nor paleobotanic data now. Main climatic tendency during the Campanian (with the exception of Latest Campanian) has been learned from isotopic composition of Campanian aragonitic ammonoid shells from the Hokkaido-South Sakhalin (Krilyon) marine basin.In contrary to Huber's et al. (2002) assumption, we expect warm greenhouse conditions during the most part of the Campanian.

  17. Elastic thickness estimates at north east passive margin of North America and its implications

    Indian Academy of Sciences (India)

    R T Ratheesh Kumar; Tanmay K Maji; Suresh Ch Kandpal; D Sengupta; Rajesh R Nair

    2011-06-01

    Global estimates of the elastic thickness (Te) of the structure of passive continental margins show wide and varying results owing to the use of different methodologies. Earlier estimates of the elastic thickness of the North Atlantic passive continental margins that used flexural modelling yielded a Te value of ∼20–100 km. Here, we compare these estimates with the Te value obtained using orthonormalized Hermite multitaper recovered isostatic coherence functions. We discuss how Te is correlated with heat flow distribution and depth of necking. The E–W segment in the southern study region comprising Nova Scotia and the Southern Grand Banks show low Te values, while the zones comprising the NE–SW zones, viz., Western Greenland, Labrador, Orphan Basin and the Northern Grand Bank show comparatively high Te values. As expected, Te broadly reflects the depth of the 200–400°C isotherm below the weak surface sediment layer at the time of loading, and at the margins most of the loading occurred during rifting. We infer that these low Te measurements indicate Te frozen into the lithosphere. This could be due to the passive nature of the margin when the loads were emplaced during the continental break-up process at high temperature gradients.

  18. Palinspastic restoration of NAVDat and its implications for the origins of magmatism in western North America

    Science.gov (United States)

    McQuarrie, N.; Oskin, M.

    2008-12-01

    Simultaneous palinspastic restoration of deformation and volcanism illuminates relationships between magmatism and tectonics in western North America. Using ArcGIS and custom software, we retrodeformed the NAVDat (North American Volcanic Database, navdat.geongrid.org) using the western North America reconstruction of McQuarrie and Wernicke (2005). We compare this data to strain rates calculated over a 50 km-grid forward-deformed from 36 Ma to present. With the deformed grid and palinspastically restored volcanic dataset we quantitatively compare rates of magmatism and deformation and evaluate the age, location, and migration of Cenozoic volcanic arcs. These relationships are shown in a series of palinspastic maps as well as an animation highlighting migrating extension and volcanism with time. We group western North America into 8 different regions with distinct relationships between strain and volcanism. In the northern Basin and Range, southern Arizona and Rio Grande rift areas, a peak in andesitic compositions reflects arc volcanism that preceded significant extension by 5-10 m.y. In the northern Basin and Range, southwestward migration of volcanism in conjunction with westward expansion of the continental margin strongly supports the contention that extension was driven by slab rollback. Southern Arizona and the Colorado River extensional corridor (CEC) have a remarkably similar migration of extension and volcanism that occurred ~10 m.y. later than in the northern Basin and Range. The migration of volcanism from southern Arizona to the CEC and Mojave Desert has been argued to reflect northwestward migration of the volcanic arc from 30 to 15 Ma. However, we note that by 20 Ma both the CEC and the Mojave region directly overlie the slab window in the Farallon plate. In this region extension peaks with or immediately after volcanism and suggests thermal failure of the lithosphere above a growing slab window. At the latitude of Death Valley there is a strong

  19. Multilocus phylogeography and population structure of common eiders breeding in North America and Scandinavia

    Science.gov (United States)

    Sonsthagen, Sarah A.; Talbot, Sandra L.; Scribner, Kim T.; McCracken, Kevin G.

    2014-01-01

    Aim:  Glacial refugia during the Pleistocene had major impacts on the levels and spatial apportionment of genetic diversity of species in northern latitude ecosystems. We characterized patterns of population subdivision, and tested hypotheses associated with locations of potential Pleistocene refugia and the relative contribution of these refugia to the post-glacial colonization of North America and Scandinavia by common eiders (Somateria mollissima). Specifically, we evaluated localities hypothesized as ice-free areas or glacial refugia for other Arctic vertebrates, including Beringia, the High Arctic Canadian Archipelago, Newfoundland Bank, Spitsbergen Bank and north-west Norway. Location: Alaska, Canada, Norway and Sweden. Methods: Molecular data from 12 microsatellite loci, the mitochondrial DNA (mtDNA) control region, and two nuclear introns were collected and analysed for 15 populations of common eiders (n = 716) breeding throughout North America and Scandinavia. Population genetic structure, historical population fluctuations and gene flow were inferred using F-statistics, analyses of molecular variance, and multilocus coalescent analyses. Results: Significant inter-population variation in allelic and haplotypic frequencies were observed (nuclear DNA FST = 0.004–0.290; mtDNA ΦST = 0.051–0.927). Whereas spatial differentiation in nuclear genes was concordant with subspecific designations, geographic proximity was more predictive of inter-population variance in mitochondrial DNA haplotype frequency. Inferences of historical population demography were consistent with restriction of common eiders to four geographic areas during the Last Glacial Maximum: Belcher Islands, Newfoundland Bank, northern Alaska and Svalbard. Three of these areas coincide with previously identified glacial refugia: Newfoundland Bank, Beringia and Spitsbergen Bank. Gene-flow and clustering analyses indicated that the Beringian refugium contributed little to common eider post

  20. Low-accommodation detrital apron alongside a basement uplift, Pennsylvanian of Midcontinent North America

    Science.gov (United States)

    Joeckel, R. M.; Nicklen, B. L.; Carlson, M. P.

    2007-04-01

    The northern end of the 650-km-long Nemaha Uplift (Nebraska and Kansas, USA) is an important example of basin-margin sedimentation in the North American Midcontinent. An apron of coarse, basal Pennsylvanian arkosic clastic sediments (BPC) was deposited on the flanks of the uplift while marine cyclothems were encroaching from the east. Small-scale fining-upward intervals, many with demonstrably erosional bases, dominate the BPC and are interpreted as overridingly fluvial in origin. Weak paleosols, desiccation cracks, and reddened intervals in the BPC record episodic subaerial exposure. Multiple, burrowed horizons and heterolithic strata of probable tidal origin and rare marine fossils also indicate episodic marine influence. The BPC appear to have been deposited as a thin apron of coalesced, alluvial fans and fan deltas. Deposition of the BPC occurred during the waning of uplift and subsequent quiescence. The comparative thinness and large-scale packaging of the BPC are compatible with the controlling effects of relict relief, regional subsidence, and eustasy, rather than ongoing, major vertical displacements along active faults. A strong autocyclic influence on sedimentation is evidenced by stacked fining-upward intervals of poorly-sorted conglomerates, sandstones, and sandy mudstones. Correlations demonstrate that the accumulation of the BPC took place over more than seven major sea-level cycles, beginning in Cherokee Group times (middle Moscovian/middle Pennsylvanian) and ending only when the eroded uplift was inundated and buried by marine cyclothems. On the basis of local correlations with marine cyclothems, and using black phosphatic shales (so-called "core shales" of Heckel, P.H., 1986. Sea-level surve for Pennsylvanian eustatic marine transgressive-regressive depositional cycles along Midcontinent outcrop belt, North America: Geology 14, 330-334., Heckel, P.H., 1994. Evaluation of evidence for glacio-eustatic control over marine Pennsylvanian cyclothems in

  1. GPS and Relative Sea-level Constraints on Glacial Isostatic Adjustment in North America

    Science.gov (United States)

    James, T. S.; Simon, K.; Henton, J. A.; Craymer, M.

    2015-12-01

    Recently, new GIA models have been developed for the Innuitian Ice Sheet and for the north-central portion of the Laurentide Ice Sheet (Simon, 2014; Simon et al., 2015). This new combined model, herein called Innu-Laur15, was developed from the ICE-5G model and load adjustments were made to improve the fit to relative sea-level observations and to GPS-constrained vertical crustal motion in the Canadian Arctic Archipelago and around Hudson Bay. Here, the predictions of Innu-Laur15 are compared to observations and other GIA models over an extended region comprising much of North America east of the Rocky Mountains. GIA predictions are made using compressible Maxwell Earth models with gravitationally self-consistent ocean loading, changing coastlines, and ocean-water inundation where marine ice retreats or floats. For this study, GPS time series are the NA12 solution (Blewitt et al., 2013) downloaded from http://geodesy.unr.edu/NGLStationPages/GlobalStationList and fit with a linear trend, annual and semi-annual terms, and offsets as indicated by station logs and by inspection of the time series. For example, a comparison of GPS observations of vertical crustal motion from the NA12 solution at 360 sites gives root-mean-square (RMS) residuals of 3.2 mm/yr (null hypothesis), 1.8 mm/yr (Innu-Laur15), and 2.9 mm/yr (ICE-5G) for the VM5a Earth model. Preliminary comparisons with other Earth models give similar patterns where Innu-Laur15 provides a better fit than ICE-5G. Further adjustments to the Innu-Laur15 ice sheet history could improve the fit to GPS rates in other regions of North America.

  2. Waterspout outbreaks over areas of Europe and North America: Environment and predictability

    Science.gov (United States)

    Sioutas, Michalis; Szilagyi, Wade; Keul, Alexander

    2013-04-01

    Waterspout outbreak occurrences are examined for the areas of the Aegean and Ionian Seas, Eastern Mediterranean, the Baltic Sea in Northern Europe and the Great Lakes of North America. Notable outbreaks included a series of 13 waterspouts on September 5, 2002, and 25 plus waterspouts on September 21, 2006 off the Cretan north coast in the Aegean Sea. Two outbreak days with 10 waterspouts each, occurred on August 11 and 13, 2006 over the Baltic Sea. During the fall of 2003 an outbreak produced about 66 waterspouts during a week over the Great Lakes of North America. A preliminary climatology of waterspout outbreak occurrences showed August as the most active month for the Baltic Sea and the Great Lakes and September for the Aegean and Ionian Seas; a feature primary related to the warmest sea surface temperatures during these months. Synoptic data indicated that a closed low (CLOSED) type pattern prevailed during waterspout outbreaks over the Baltic and the Aegean and Ionian Seas and a longwave (LW) type over the Great Lakes. Thermodynamic, wind and moisture data indicated a marginally unstable environment for most waterspout outbreaks. A steep thermal gradient between the water surface and lowest layers proved to be a primary factor for Great Lakes waterspout outbreak occurrences. For the Baltic Sea, the primary factors were balanced between the thermal contrast in the lowest layers and the total positive buoyancy. For the Aegean and Ionian Seas, positive buoyancy was the dominant factor. Selected waterspout outbreak case studies are investigated in order to present specific synoptic, thermodynamic features and predictability for the three areas. The Szilagyi waterspout nomogram, which is used as a forecasting tool, was applied together with the Szilagyi waterspout index (SWI) and found to be strongly correlated with outbreak occurrences for the three geographical areas.

  3. North Korea: A Geographical Analysis.

    Science.gov (United States)

    Palka, Eugene J., Ed.; Galgano, Francis A., Ed.

    North Korea is a country about the size of the state of New York, inhabited by about 23 million people. It came into existence after the conclusion of World War II following decades of occupation of the Korean Peninsula by the Japanese empire. Dividing the peninsula into North and South Korea was the politically expedient solution to one of the…

  4. The Cambrian-Ordovician rocks of Sonora, Mexico, and southern Arizona, southwestern margin of North America (Laurentia): chapter 35

    Science.gov (United States)

    Page, William R.; Harris, Alta C.; Repetski, John E.; Derby, James R.; Fritz, R.D.; Longacre, S.A.; Morgan, W.A.; Sternbach, C.A.

    2013-01-01

    Cambrian and Ordovician shelf, platform, and basin rocks are present in Sonora, Mexico, and southern Arizona and were deposited on the southwestern continental margin of North America (Laurentia). Cambrian and Ordovician rocks in Sonora, Mexico, are mostly exposed in scattered outcrops in the northern half of the state. Their discontinuous nature results from extensive Quaternary and Tertiary surficial cover, from Tertiary and Mesozoic granitic batholiths in western Sonora, and from widespread Tertiary volcanic deposits in the Sierra Madre Occidental in eastern Sonora. Cambrian and Ordovician shelf rocks were deposited as part of the the southern miogeocline on the southwestern continental margin of North America.

  5. The influence of chilling requirement on the southern distribution limit of exotic Russian olive (Elaeagnus angustifolia) in western North America

    Science.gov (United States)

    Guilbault, Kimberly R.

    2011-01-01

    Russian olive (Elaeagnus angustifolia L.), a Eurasian tree, is now a dominant species along rivers in western North America. The southern boundary of Russian olive distribution in western North America runs through southern California, Arizona, New Mexico and Texas. I related the distributional pattern of Russian olive to temperature regime and investigated potential temperature-dependent mechanisms that might explain this distributional limit. Specifically, I investigated whether lack of cold temperatures at the southern limit may prevent the accumulation of sufficient chilling and inhibit dormancy loss of seeds and buds, potentially constraining Russian olive's southern distribution boundary.

  6. Increasing ozone in marine boundary layer inflow at the west coasts of North America and Europe

    Directory of Open Access Journals (Sweden)

    D. D. Parrish

    2009-02-01

    Full Text Available An effective method is presented for determining the ozone (O3 mixing ratio in the onshore flow of marine air at the North American west coast. By combining the data available from all marine boundary layer (MBL sites with simultaneous wind data, decadal temporal trends of MBL O3 in all seasons are established with high precision. The average springtime temporal trend over the past two decades is 0.46 ppbv/yr with a 95% confidence limit of 0.13 ppbv/yr, and statistically significant trends are found for all seasons except autumn, which does have a significantly smaller trend than other seasons. The average trend in mean annual ozone is 0.34±0.09 ppbv/yr. These decadal trends at the North American west coast present a striking comparison and contrast with the trends reported for the European west coast at Mace Head, Ireland. The trends in the winter, spring and summer seasons compare well at the two locations, while the Mace Head trend is significantly greater in autumn. Even though the trends are similar, the absolute O3 mixing ratios differ markedly, with the marine air arriving at Europe in all seasons containing 7±2 ppbv higher ozone than marine air arriving at North America. Further, the ozone mixing ratios at the North American west coast show no indication of stabilizing as has been reported for Mace Head. In a larger historical context the background boundary layer O3 mixing ratios over the 130 years covered by available data have increased substantially (by a factor of two to three, and this increase continues at present, at least in the MBL of the Pacific coast region of North America. The reproduction of the increasing trends in MBL O3 over the past two decades, as well as the difference in the O3 mixing ratios between the two coastal regions will present a significant challenge for global chemical transport models. Further, the ability of the models to at least semi

  7. Collapse of the western North America climate dipole during the MCA and LIA

    Science.gov (United States)

    Asmerom, Y.; Polyak, V. J.; Rasmussen, J.; Burns, S. J.; Lachniet, M. S.

    2011-12-01

    Understanding of the teleconnections between regional climate regimes and the time-scale of the stability of these teleconnections is crucial for building predictive models of climate change. Using annually-resolved speleothem physical (band thickness, hiatus and mineralogy) and oxygen and carbon isotopic effective moisture proxy data, we show climate variability in the southwestern United States (SW) during the critical Medieval Climate Anomaly and Little Ice Age (LIA) intervals. Although the MCA overall was not markedly drier than the wet latter half of the LIA, it was punctuated by multiple megadroughts. The driest interval was the early LIA, during which we identify an extended multi-century drought, which we will refer to as a Super Drought (SD), occurring during the early LIA ca. AD 1350 to AD 1650. There is a well-established dipole response to Pacific Decadal Oscillation (PDO) and El Nino-Southern Oscillation (ENSO) variability between the SW and northwestern United States (NW), and the SW and the Asian monsoon during the modern and overall Holocene climate regime. Our data indicate that this climate dipole apparently collapsed during the MCA-LIA, extending back to about 300 AD, such that pluvial and drought intervals in the SW and NW, and SW and Asian monsoon occur contemporaneously over this period. The modern positive relationship between moisture and the PDO observed in the SW is also reversed. During this interval the PDO is negatively correlated with SW moisture amount. In addition, the strong solar control of Holocene climate observed previously in western North America and the Asian monsoon is weakened during parts of this interval, such that solar maxima and minima do not correlate coherently with precipitation variability both in North America and the Asian monsoon. The MCA-early LIA period in which the megadroughts dominate occurs within the prominently positive phase of the North Atlantic Oscillation (NAO). One potential mechanism of propagating

  8. Low prevalence of Trichomonas gallinae in urban and migratory Cooper's Hawks in northcentral North America

    Science.gov (United States)

    Rosenfield, Robert N.; Taft, Stephen J.; Stout, William E.; Driscoll, Timothy G.; Evans, David L.; Bozek, Michael A.

    2009-01-01

    Trichomoniasis is a digestive tract disease caused by ingestion of the protozoan Trichomonas gallinae. This disease can be a significant source of mortality. No deaths of nestlings could be attributed to trichomoniasis in Cooper's Hawks (Accipiter cooperii) breeding in urban and rural environs in Wisconsin, North Dakota, and British Columbia. We detected T. gallinae in four (5.2%) of 77 nestling Cooper's Hawks during 2006 and 2007 among 42 urban nests on new study areas in southeast Wisconsin and eastern North Dakota/western Minnesota. All four infected young fledged. We did not detect T. gallinae in 52 breeding adult Cooper's Hawks on two urban study sites, nor in 28 migrant hatching year (n  =  24) and adult (n  =  4) Cooper's Hawks at Hawk Ridge Nature Reserve, Duluth, Minnesota in 2006–2007. Overall, we detected T. gallinae in only 2.5% of 157 Cooper's Hawks in northcentral North America. These results suggest a low prevalence of T. gallinae in Cooper's Hawks in the northern part of this hawk's breeding range.

  9. Nazca - South America Convergence and Motion of the North Andes Block

    Science.gov (United States)

    La Femina, P. C.; Mora-paez, H.; Mothes, P. A.; Ruiz, G.

    2012-12-01

    The North Andes block (NAB) is a hypothesized tectonic block that moves (escapes) north-northeast relative to a stable South American reference frame. The motion of this block is thought to be derived by the collision of the Carnegie Ridge in southern Ecuador and/or by oblique convergence and high degrees of interplate coupling north of the ridge (i.e., strain partitioning). We investigate the kinematics of NAB motion utilizing a velocity field based on new continuous GPS networks and existing episodic GPS data in Ecuador and Colombia. The new velocity field and published earthquake slip vectors are inverted to solve for the Euler vector of the NAB and interseismic elastic strain accumulation on block-bounding faults using a block modeling approach. At the latitude of Ecuador, the NAB is rigid with transpressional deformation accommodating northeastward motion along its boundary with South America. In central to northern Colombia, the NAB is dissected by several prominent shear zones. We test a suite of block models to investigate the tectonic nature of the NAB and the style of faulting in the upper plate accommodating block motion. Through the estimation of elastic strain accumulation on all block-bounding faults, we improve the understanding of interseismic coupling along a convergent margin capable of producing M>8 earthquakes and upper plate faults capable of generating M>6 earthquakes.

  10. Comparative climatological study of large-scale traveling ionospheric disturbances over North America and China in 2011-2012

    Science.gov (United States)

    Ding, Feng; Wan, Weixing; Li, Qiang; Zhang, Rui; Song, Qian; Ning, Baiqi; Liu, Libo; Zhao, Biqiang; Xiong, Bo

    2014-01-01

    This paper describes a comparative study of the climatology of large-scale traveling ionospheric disturbances (LSTIDs) over North America and China based on observations obtained in 2011-2012 using two GPS networks characterized by dense regional coverage. We identified a total of 390 LSTIDs in China and 363 events in North America. These can be categorized into three types, namely south, north, and westward propagating LSTIDs. The southward LSTIDs over North America show similar diurnal and seasonal variations to those of geomagnetic disturbances, but the southward LSTIDs over China do not show such variations. The occurrence of southward LSTIDs over China increases at ~1-2 h after the time of geomagnetic activity maximum; this increase lasts several hours until the geomagnetic minimum, which happens during the local evening. The southward LSTIDs over North America show a semiannual variation with two peaks in March and October, while the southward LSTIDs over China show a major peak in January. Northward LSTIDs occur much less frequently than their southward counterparts, and they are mainly observed in China. They mostly occur during geomagnetic activity maximum, indicating a possible relation with the degree of geomagnetic activity. Westward LSTIDs are seen in both regions during local sunrise and may be excited by the moving solar terminator. No relationship was found between these latter LSTIDs and the geomagnetic disturbances. The propagation direction of westward events changed from northwestward during winter solstice to southwestward at summer solstice. This is consistent with the seasonal orientation of the solar terminator.

  11. Patagonian Glacier Advances in Concert with those in Western North America

    Science.gov (United States)

    Maurer, M. K.; Menounos, B.; Clague, J. J.; osborn, G.

    2012-12-01

    The question of whether Holocene glacier advances in the Northern and Southern hemispheres are synchronous remains open. Here we report on the evidence for late Holocene advances at Stoppani Glacier (54.78° S, 68.98° W), 50 km west of Ushuaia, Argentina, and compare this record to glacier fluctuations in western North America. The glacier is an outlet glacier of the Darwin Cordillera icefield, has an area of 92 km2 and descends to 80 m asl. Wood mats containing stumps in growth position are separated by units of till in a 100-m-high section through the northeast lateral moraine. Radiocarbon ages on the wood mats and stumps decrease up-section, demonstrating that Stoppani Glacier advanced successively farther over the past 3800 years. The earliest of the advances is recorded by a till overlying peat containing wood that returned a calibrated radiocarbon age of 3.83-3.64 ka (kilo calendar years BP). This advance coincides with a well documented glacier advance in western Canada, the so-called '4.2 ka event' [4.2-3.8 ka]. Stoppani Glacier further thickened and overran stumps in growth position at 3.16-2.95 and at 2.86-2.76 ka; both of these events are contemporaneous with widespread advances of alpine glaciers in British Columbia and Alberta. A fourth advance of Stoppani Glacier at about 2.30-2.01 ka coincides with advances of Deming Glacier on Mount Baker, Washington, USA [2.35-2.15 ka], and several glaciers in the Coast Mountains of British Columbia, Canada. The final advance of Stoppani Glacier began about 0.29 ka when the glacier thickened, overran a vegetated surface, and deposited till that forms the crest of the moraine. This advance coincides with the maximum, classical, Little Ice Age advance of nearly all glaciers in western North America. Collectively, our data indicate that Stoppani Glacier advanced in step with glaciers in western North America during the late Holocene. The most parsimonious explanation is that century-scale climate forcing

  12. Shear wave velocity structure in North America from large-scale waveform inversions of surface waves

    Science.gov (United States)

    Alsina, D.; Woodward, R.L.; Snieder, R.K.

    1996-01-01

    A two-step nonlinear and linear inversion is carried out to map the lateral heterogeneity beneath North America using surface wave data. The lateral resolution for most areas of the model is of the order of several hundred kilometers. The most obvious feature in the tomographic images is the rapid transition between low velocities in the technically active region west of the Rocky Mountains and high velocities in the stable central and eastern shield of North America. The model also reveals smaller-scale heterogeneous velocity structures. A high-velocity anomaly is imaged beneath the state of Washington that could be explained as the subducting Juan de Fuca plate beneath the Cascades. A large low-velocity structure extends along the coast from the Mendocino to the Rivera triple junction and to the continental interior across the southwestern United States and northwestern Mexico. Its shape changes notably with depth. This anomaly largely coincides with the part of the margin where no lithosphere is consumed since the subduction has been replaced by a transform fault. Evidence for a discontinuous subduction of the Cocos plate along the Middle American Trench is found. In central Mexico a transition is visible from low velocities across the Trans-Mexican Volcanic Belt (TMVB) to high velocities beneath the Yucatan Peninsula. Two elongated low-velocity anomalies beneath the Yellowstone Plateau and the eastern Snake River Plain volcanic system and beneath central Mexico and the TMVB seem to be associated with magmatism and partial melting. Another low-velocity feature is seen at depths of approximately 200 km beneath Florida and the Atlantic Coastal Plain. The inversion technique used is based on a linear surface wave scattering theory, which gives tomographic images of the relative phase velocity perturbations in four period bands ranging from 40 to 150 s. In order to find a smooth reference model a nonlinear inversion based on ray theory is first performed. After

  13. Reliable, Economic, Efficient CO2 Heat Pump Water Heater for North America

    Energy Technology Data Exchange (ETDEWEB)

    Radcliff, Thomas D; Sienel, Tobias; Huff, Hans-Joachim; Thompson, Adrian; Sadegh, Payman; Olsommer, Benoit; Park, Young

    2006-12-31

    Adoption of heat pump water heating technology for commercial hot water could save up to 0.4 quads of energy and 5 million metric tons of CO2 production annually in North America, but industry perception is that this technology does not offer adequate performance or reliability and comes at too high of a cost. Development and demonstration of a CO2 heat pump water heater is proposed to reduce these barriers to adoption. Three major themes are addressed: market analysis to understand barriers to adoption, use of advanced reliability models to design optimum qualification test plans, and field testing of two phases of water heater prototypes. Market experts claim that beyond good performance, market adoption requires 'drop and forget' system reliability and a six month payback of first costs. Performance, reliability and cost targets are determined and reliability models are developed to evaluate the minimum testing required to meet reliability targets. Three phase 1 prototypes are designed and installed in the field. Based on results from these trials a product specification is developed and a second phase of five field trial units are built and installed. These eight units accumulate 11 unit-years of service including 15,650 hours and 25,242 cycles of compressor operation. Performance targets can be met. An availability of 60% is achieved and the capability to achieve >90% is demonstrated, but overall reliability is below target, with an average of 3.6 failures/unit-year on the phase 2 demonstration. Most reliability issues are shown to be common to new HVAC products, giving high confidence in mature product reliability, but the need for further work to minimize leaks and ensure reliability of the electronic expansion valve is clear. First cost is projected to be above target, leading to an expectation of 8-24 month payback when substituted for an electric water heater. Despite not meeting all targets, arguments are made that an industry leader could

  14. The Unified North American Soil Map and its implication on the soil organic carbon stock in North America

    Directory of Open Access Journals (Sweden)

    S. Liu

    2012-10-01

    Full Text Available The Unified North American Soil Map (UNASM was developed to provide more accurate regional soil information for terrestrial biosphere modeling. The UNASM combines information from state-of-the-art US STATSGO2 and Soil Landscape of Canada (SLCs databases. The area not covered by these datasets is filled with the Harmonized World Soil Database version 1.1 (HWSD1.1. The UNASM contains maximum soil depth derived from the data source as well as seven soil attributes (including sand, silt, and clay content, gravel content, organic carbon content, pH, and bulk density for the top soil layer (0–30 cm and the sub soil layer (30–100 cm respectively, of the spatial resolution of 0.25° in latitude and longitude. There are pronounced differences in the spatial distributions of soil properties and soil organic carbon between UNASM and HWSD, but the UNASM overall provides more detailed and higher-quality information particularly in Alaska and Central Canada. To provide more accurate and up-to-date estimate of soil organic carbon stock in North America, we incorporated Northern Circumpolar Soil Carbon Database (NCSCD into the UNASM. The estimate of total soil organic carbon mass in the upper 100 cm soil profile based on the improved UNASM is 347.70 Pg, of which 24.7% is under trees, 14.2% is under shrubs, and 1.3% is under grasses and 3.8% under crops. This UNASM data will provide a resource for use in land surface and terrestrial biogeochemistry modeling both for input of soil characteristics and for benchmarking model output.

  15. The Unified North American Soil Map and its implication on the soil organic carbon stock in North America

    Directory of Open Access Journals (Sweden)

    S. Liu

    2013-05-01

    Full Text Available The Unified North American Soil Map (UNASM was developed to provide more accurate regional soil information for terrestrial biosphere modeling. The UNASM combines information from state-of-the-art US STATSGO2 and Soil Landscape of Canada (SLCs databases. The area not covered by these datasets is filled by using the Harmonized World Soil Database version 1.21 (HWSD1.21. The UNASM contains maximum soil depth derived from the data source as well as seven soil attributes (including sand, silt, and clay content, gravel content, organic carbon content, pH, and bulk density for the topsoil layer (0–30 cm and the subsoil layer (30–100 cm, respectively, of the spatial resolution of 0.25 degrees in latitude and longitude. There are pronounced differences in the spatial distributions of soil properties and soil organic carbon between UNASM and HWSD, but the UNASM overall provides more detailed and higher-quality information particularly in Alaska and central Canada. To provide more accurate and up-to-date estimate of soil organic carbon stock in North America, we incorporated Northern Circumpolar Soil Carbon Database (NCSCD into the UNASM. The estimate of total soil organic carbon mass in the upper 100 cm soil profile based on the improved UNASM is 365.96 Pg, of which 23.1% is under trees, 14.1% is in shrubland, and 4.6% is in grassland and cropland. This UNASM data will provide a resource for use in terrestrial ecosystem modeling both for input of soil characteristics and for benchmarking model output.

  16. MODIS Snowcover in North America: A Comparison of Winter 2013/14 and 2014/15 to Median Condition

    Science.gov (United States)

    Trubilowicz, J. W.; Floyd, B. C.; D'Amore, D. V.; Bidlack, A.

    2015-12-01

    The winters from 2013-2015 had exceptionally low snow-packs in much of western North America. In particular, the winter of 2014/2015 had the lowest peak snow-water-equivalent (SWE) depths ever recorded in many areas of the Pacific Northwest. These low snow-packs have contributed to drought conditions from British Columbia to California. Along with the low SWE values, the snow covered area (SCA) of the previous two winters has been a significant departure from normal conditions. SCA is related to SWE, rain-on-snow events and the seasonal water supply, provides insulation for plant root systems from late season frost, and is an important factor in forest fire hazard, delaying the start of soil and fuel drying. Remote sensing can be a useful tool to monitor SCA over large regions, with the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments providing a suitable temporal (twice daily), and spatial resolution (500m) to create detailed maps, even with high frequencies of cloud covered days. While comparison of SWE at snow monitoring sites to historical values is a standard analysis, doing the same for SCA has been difficult due to the technical and logistical problems related to processing the large amounts of spatial data required to determine a 'normal' annual SCA cycle. Through the use of new cloud-based computation methods from Google Earth Engine, we have calculated the monthly median (from 2002-2015) MODIS SCA, at a 500 m resolution, for all of the major Pacific draining watersheds of North America. Determining the 'normal' SCA cycle of the past 13 years allowed us to compare the past two winters to the median SCA levels, showing which basins have seen the most significant departures from normal SCA levels. Results indicate more significant departures from normal in basins with significant maritime-influenced snow-packs.

  17. A quantitative and novel approach to the prioritization of zoonotic diseases in North America: a public perspective.

    Directory of Open Access Journals (Sweden)

    Victoria Ng

    Full Text Available BACKGROUND: Zoonoses account for over half of all communicable diseases causing illness in humans. As there are limited resources available for the control and prevention of zoonotic diseases, a framework for their prioritization is necessary to ensure resources are directed into those of highest importance. Although zoonotic outbreaks are a significant burden of disease in North America, the systematic prioritization of zoonoses in this region has not been previously evaluated. METHODOLOGY/PRINCIPAL FINDINGS: This study describes the novel use of a well-established quantitative method, conjoint analysis (CA, to identify the relative importance of 21 key characteristics of zoonotic diseases that can be used for their prioritization in Canada and the US. Relative importance weights from the CA were used to develop a point-scoring system to derive a recommended list of zoonoses for prioritization in Canada and the US. Over 1,500 participants from the general public were recruited to complete the online survey (761 from Canada and 778 from the US. Hierarchical Bayes models were fitted to the survey data to derive CA-weighted scores. Scores were applied to 62 zoonotic diseases of public health importance in Canada and the US to rank diseases in order of priority. CONCLUSIONS/SIGNIFICANCE: This was the first study to describe a systematic and quantitative approach to the prioritization of zoonoses in North America involving public participants. We found individuals with no prior knowledge or experience in prioritizing zoonoses were capable of producing meaningful results using CA as a novel quantitative approach to prioritization. More similarities than differences were observed between countries suggesting general agreement in disease prioritization between Canadians and Americans. We demonstrate CA as a potential tool for the prioritization of zoonoses; other prioritization exercises may also consider this approach.

  18. The Atmospheric Mercury Network: measurement and initial examination of an ongoing atmospheric mercury record across North America

    Directory of Open Access Journals (Sweden)

    D. A. Gay

    2013-04-01

    Full Text Available The National Atmospheric Deposition Program (NADP developed and operates a collaborative network of atmospheric mercury monitoring sites based in North America – the Atmospheric Mercury Network (AMNet. The justification for the network was growing interest and demand from many scientists and policy makers for a robust database of measurements to improve model development, assess policies and programs, and improve estimates of mercury dry deposition. Many different agencies and groups support the network, including federal, state, tribal, and international governments, academic institutions, and private companies. AMNet has added two high elevation sites outside of continental North America in Hawaii and Taiwan because of new partnerships forged within NADP. Network sites measure concentrations of atmospheric mercury fractions using automated, continuous mercury speciation systems. The procedures that NADP developed for field operations, data management, and quality assurance ensure that the network makes scientifically valid and consistent measurements. AMNet reports concentrations of hourly gaseous elemental mercury (GEM, two-hour gaseous oxidized mercury (GOM, and two-hour particulate-bound mercury less than 2.5 microns in size (PBM2.5. As of January 2012, over 450 000 valid observations are available from 30 stations. The AMNet also collects ancillary meteorological data and information on land-use and vegetation, when available. We present atmospheric mercury data comparisons by time (3 yr at 22 unique site locations. Highlighted are contrasting values for site locations across the network: urban versus rural, coastal versus high-elevation and the range of maximum observations. The data presented should catalyze the formation of many scientific questions that may be answered through further in-depth analysis and modeling studies of the AMNet database. All data and methods are publically available through an online database on the NADP

  19. The Curious Decoupling of Magmatism and Plate Tectonics During the Cenozoic in Western North America: Insight From the NAVDAT Database

    Science.gov (United States)

    Glazner, A. F.; Walker, J. D.; Farmer, G. L.; Bowers, T. D.

    2004-12-01

    Since the widespread acceptance of plate tectonics, magmatism in the western U.S. has been explained by subduction along the west coast of North America and destruction of the subduction system by development of the San Andreas transform fault system. However, re-analysis of space-time patterns of magmatism in western North America calls many of these inferred patterns of magmatism into question. Animation of space-time patterns found in the developing NAVDAT dataset (which currently hosts about 10,000 Cenozoic age and/or geochemical analyses; navdat.geongrid.org), demonstrates that: (1) subduction-type (e.g., intermediate) volcanism is poorly linked to the subduction system; (2) there is little evidence that slab windows controlled magmatism; (3) magmatism was clearly migratory, but not in ways that can be explained by plate-tectonic processes; and (4) magmatism was migratory at length scales ranging from 1000s of km (continental) to 10s of km (county). Several space-time patterns are evident in the NAVDAT animations, including: (1) a sweep from Montana into Nevada from 50 to about 20 Ma; (2) a clockwise sweep around the Colorado Plateau from New Mexico to southern Nevada, from about 30 to 15 Ma; (3) a burst of magmatism at about 16 Ma in northern Nevada, followed by outward sweeps to Yellowstone, central Oregon, and the Sierra Nevada; (4) a burst of magmatism in the Sierra Nevada at 3.5 Ma; and (5) several local migrations, including from Phoenix north onto the Colorado Plateau and from the San Francisco Bay area north to the Geysers geothermal field. Some of these patterns have been tied to specific events (e.g., impingement of the Yellowstone plume and Pliocene delamination), but the others are difficult to relate to plate-tectonic events. They may be caused by local tectonic events (propagating rifts?), minor convective rolls in the asthenosphere, lithospheric delamination, or delamination of a flat Laramide slab. Whatever their origin, database animation

  20. Evaluation of operational online-coupled regional air quality models over Europe and North America in the context of AQMEII phase 2. Part II: Particulate matter

    NARCIS (Netherlands)

    Im, U.; Bianconi, R.; Solazzo, E.; Kioutsioukis, I.; Badia, A.; Balzarini, A.; Baro, R.; Bellasio, R.; Brunner, D.; Chemel, C.; Curci, G.; Denier van der Gon, H.A.C.; Flemming, J.; Forkel, R.; Giordano, L.; Jimenez-Guerrero, P.; Hirtl, M.; Hodzic, A.; Honzak, L.; Jorba, O.; Knote, C.; Makar, P.A.; Manders-Groot, A.M.M.; Neal, L.; Perez, J.L.; Pirovano, G.; Pouliot, G.; San Jose, R.; Savage, N.; Schroder, W.; Sokhi, R.S.; Syrakov, D.; Torian, A.; Tucella, P.; Wang, K.; Werhahn, J.; Wolke, R.; Zabkar, R.; Zhang, Y.; Zhang, J.; Hogrefe, C.; Galmarini, S.

    2014-01-01

    The second phase of the Air Quality Model Evaluation International Initiative (AQMEII) brought together seventeen modeling groups from Europe and North America, running eight operational online-coupled air quality models over Europe and North America using common emissions and boundary conditions. T

  1. Acculturation, dietary acceptability and diabetes management among Chinese in North America

    Directory of Open Access Journals (Sweden)

    Feiyue eDeng

    2013-08-01

    Full Text Available Immigrants to a new country face many challenges when diagnosed with type 2 diabetes, a chronic disease with a complex treatment involving both medical and behavioral interventions. These challenges will depend upon the extent to which the patient has adapted to the new country’s social and cultural norms, as well as individual factors such as age, education and gender. This adaptation is termed acculturation. With respect to nutritional interventions for type 2 diabetes, uptake and adherence over the long term will depend upon overall health literacy, the cultural acceptability of the recommended diet. This review has focused on acculturation and its effects on diabetes management in ethnic Chinese in North America as an example of one populous minority and the challenges faced in adopting nutritional recommendations. Research directions and practical considerations are suggested.

  2. Effect of climate change on surface ozone over North America, Europe, and East Asia

    Science.gov (United States)

    Schnell, Jordan L.; Prather, Michael J.; Josse, Beatrice; Naik, Vaishali; Horowitz, Larry W.; Zeng, Guang; Shindell, Drew T.; Faluvegi, Greg

    2016-04-01

    The effect of future climate change on surface ozone over North America, Europe, and East Asia is evaluated using present-day (2000s) and future (2100s) hourly surface ozone simulated by four global models. Future climate follows RCP8.5, while methane and anthropogenic ozone precursors are fixed at year 2000 levels. Climate change shifts the seasonal surface ozone peak to earlier in the year and increases the amplitude of the annual cycle. Increases in mean summertime and high-percentile ozone are generally found in polluted environments, while decreases are found in clean environments. We propose that climate change augments the efficiency of precursor emissions to generate surface ozone in polluted regions, thus reducing precursor export to neighboring downwind locations. Even with constant biogenic emissions, climate change causes the largest ozone increases at high percentiles. In most cases, air quality extreme episodes become larger and contain higher ozone levels relative to the rest of the distribution.

  3. Updated determination of stress parameters for nine well-recorded earthquakes in eastern North America

    Science.gov (United States)

    Boore, D.M.

    2012-01-01

    Stress parameters (????) are determined for nine relatively wellrecorded earthquakes in eastern North America for ten attenuation models. This is an update of a previous study by Boore et al. (2010). New to this paper are observations from the 2010 Val des Bois earthquake, additional observations for the 1988 Saguenay and 2005 Riviere du Loup earthquakes, and consideration of six attenuation models in addition to the four used in the previous study. As in that study, it is clear that ???? depends strongly on the rate of geometrical spreading (as well as other model parameters). The observations necessary to determine conclusively which attenuation model best fits the data are still lacking. At this time, a simple 1/R model seems to give as good an overall fit to the data as more complex models.

  4. Foodborne outbreaks of cyclosporiasis have arisen in North America. Is the United Kingdom at risk?

    Science.gov (United States)

    Chalmers, R M; Nichols, G; Rooney, R

    2000-03-01

    Cyclospora cayetanensis is a parasitic protozoon that causes prolonged watery diarrhoea. It is endemic in some developing countries, and recent foreign travel is often used as a selection criterion for screening in the United Kingdom (UK). Epidemiological investigations of outbreaks of cyclosporiasis among people in the United States and Canada who had not travelled abroad showed the infection to be foodborne and often associated with foods eaten raw. These included raspberries imported from Guatemala, and pesto (made with basil) and lettuce from other sources. Such foods are also being imported in increasing amounts to the UK, but no outbreaks have been documented, perhaps because none has occurred or because of poor ascertainment. This paper reviews the outbreaks reported from North America, evaluates the risks to the UK population, and suggests how surveillance could be improved.

  5. Four emerging arboviral diseases in North America: Jamestown Canyon, Powassan, chikungunya, and Zika virus diseases.

    Science.gov (United States)

    Pastula, Daniel M; Smith, Daniel E; Beckham, J David; Tyler, Kenneth L

    2016-06-01

    Arthropod-borne viruses, or arboviruses, are viruses that are transmitted through the bites of mosquitoes, ticks, or sandflies. There are numerous arboviruses throughout the world capable of causing human disease spanning different viral families and genera. Recently, Jamestown Canyon, Powassan, chikungunya, and Zika viruses have emerged as increasingly important arboviruses that can cause human disease in North America. Unfortunately, there are currently no proven disease-modifying therapies for these arboviral diseases, so treatment is largely supportive. Given there are also no commercially available vaccines for these four arboviral infections, prevention is the key. To prevent mosquito or tick bites that might result in one of these arboviral diseases, people should wear long-sleeved shirts and pants while outside if feasible, apply insect repellant when going outdoors, using window screens or air conditioning to keep mosquitoes outside, and perform tick checks after being in wooded or brushy outdoor areas. PMID:26903031

  6. Inverted barometer contributions to recent sea level changes along the northeast coast of North America

    Science.gov (United States)

    Piecuch, Christopher G.; Ponte, Rui M.

    2015-07-01

    Regional sea level (SL) changes reflect dynamic and isostatic ocean effects. Recent works have interpreted accelerated and extreme SL changes along the northeast coast of North America primarily in terms of dynamic changes; however, dedicated study of isostatic changes related to surface atmospheric pressure loading—the inverted barometer (IB) effect—has been lacking. This investigation uses five different atmospheric pressure products to analyze the influence of the IB effect on annual mean SL from tide gauge records. The IB effect explains ˜25% of interannual SL variance and accounts for ˜50% of the magnitude of a recent extreme event of SL rise along Atlantic Canada and New England. Estimated IB effects also amount to ˜10-30% of recent multidecadal SL accelerations over the Mid-Atlantic Bight and Southern New England. These findings reiterate the need for careful estimation and removal of isostatic effects for studies of dynamic SL.

  7. Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America.

    Science.gov (United States)

    Eads, David A; Biggins, Dean E

    2015-08-01

    Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research. PMID:25817984

  8. Volatile organic compounds in indoor air: A review ofconcentrations measured in North America since 1990

    Energy Technology Data Exchange (ETDEWEB)

    ATHodgson@lbl.gov

    2003-04-01

    Central tendency and upper limit concentrations of volatile organic compounds (VOCs) measured in indoor air are summarized and reviewed. Data were obtained from published cross-sectional studies of residential and office buildings conducted in North America from 1990through the present. VOC concentrations in existing residences reported in 12 studies comprise the majority of the data set. Central tendency and maximum concentrations are compared between new and existing residences and between existing residences and office buildings. Historical changes in indoor VOC concentrations since the Clean Air Act Amendments of 1990 are explored by comparing the current data set with two published reviews of previous data obtained primarily in the 1980s. These historical comparisons suggest average indoor concentrations of some toxic air contaminants, such as 1,1,1-trichloroethane have decreased.

  9. Using lake sediment records to reconstruct bark beetle disturbances in western North America

    Directory of Open Access Journals (Sweden)

    Jesse Lee Morris

    2013-12-01

    Full Text Available The recent outbreak of native bark beetles in western North America is unprecedented in severity and scale, at least during the historical period. The aim of this work is to develop a proxy-based methodology to understand how bark beetle disturbances are recorded in lake sediments. Three hypotheses are tested to determine how the ecological impacts of severe spruce beetle (Dendroctonus rufipennis disturbances are recorded following mortality of Engelmann spruce (Picea engelmannii. Outbreaks are hypothesized to: (1 decrease the ratio of spruce to fir pollen; (2 increase soil erosion and mobilize terrestrial C; and (3 leach foliar N, enhancing algal productivity. To test these hypotheses, sediment cores from spruce beetle-affected basins were analyzed for pollen, insect remains, organic and minerogenic content, and isotopic and elemental concentrations. The dataset was tested statistically using generalized linear mixed models (GLMMs to determine if the response variables differed significantly between outbreak and non-outbreak periods. 

  10. Attribution of spatial and temporal variations in terrestrial methane flux over North America

    Directory of Open Access Journals (Sweden)

    X. F. Xu

    2010-11-01

    Full Text Available The attribution of spatial and temporal variations in terrestrial methane (CH4 flux is essential for assessing and mitigating CH4 emission from terrestrial ecosystems. In this study, we used a process-based model, the Dynamic Land Ecosystem Model (DLEM, in conjunction with spatial data of six major environmental factors to attribute the spatial and temporal variations in the terrestrial methane (CH4 flux over North America from 1979 to 2008 to six individual driving factors and their interaction. Over the past three decades, our simulations indicate that global change factors accumulatively contributed 23.51 ± 9.61 T g CH4-C (1 Tg = 1012 g emission over North America, among which ozone (O3 pollution led to a reduced CH4 emission by 2.30 ± 0.49 T g CH4-C. All other factors including climate variability, nitrogen (N deposition, elevated atmospheric carbon dioxide (CO2, N fertilizer application, and land conversion enhanced terrestrial CH4 emissions by 19.80 ± 12.42 T g CH4-C, 0.09 ± 0.02 T g CH4-C, 6.80 ± 0.86 T g CH4-C, 0.01 ± 0.001 T g CH4-C, and 3.95 ± 0.38 T g CH4-C, respectively, and interaction between/among these global change factors led to a decline of CH4 emission by 4.84 ± 7.74 T g CH4-C. Climate variability and O3 pollution suppressed, while other factors stimulated CH4 emission over the USA; climate variability significantly enhanced, while all the other factors exerted minor effects, positive or negative, on CH4 emission in Canada; Mexico functioned as a sink for atmospheric CH4 with a major contribution from climate change. Climatic variability dominated the inter-annual variations in terrestrial CH4 flux at both continental and country levels. Precipitation played an important role in

  11. An appeal to humanity: legal victory in favour of North America's only supervised injection facility: Insite

    Directory of Open Access Journals (Sweden)

    Small Dan

    2010-10-01

    Full Text Available Abstract Canada's federal government has once again failed to shut North America's only authorized supervised injection facility: Insite. A majority ruling issued by the BC Court of Appeal on 15 January 2010 upheld an earlier British Columbia Supreme Court ruling in 2008 that protected the rights of injection drug users (IDUs to access Insite as a health facility as per the Charter of Rights and Freedoms component of the Constitution of Canada. The majority decision from Honourable Madam Justices Rowles, Huddart and Smith also established a jurisdictional victory safeguarding Insite as most appropriately run under the authority of the province of British Columbia rather than the federal Government of Canada. The Federal Government has appealed the case to the Supreme Court of Canada. A hearing date has been set for 12 May 2011. The appeal will be a legal one but even more so, it will be an appeal to humanity.

  12. Psychobiography Training in Psychology in North America: Mapping the Field and Charting a Course.

    Science.gov (United States)

    Ponterotto, Joseph G; Reynolds, Jason D; Morel, Samantha; Cheung, Linda

    2015-08-01

    Psychobiography holds an important position in the history of psychology, yet little is known about the status of psychobiographical training and dissertation research in psychology departments. This brief report identified psychobiography courses throughout North America and content analyzed a sample of 65 psychobiography dissertations to discern the theories and methods that have most commonly anchored this research. Results identified few psychology courses specifically in psychobiography, with a larger number of courses incorporating psychobiographical and/or narrative elements. With regard to psychobiography dissertations, the majority focused on artists, pioneering psychologists, and political leaders. Theories undergirding psychobiographical studies were most frequently psychoanalytic and psychodynamic. Methodologically, a majority of the dissertations were anchored in constructivist (discovery-oriented) qualitative procedures, with a minority incorporating mixed methods designs. The authors highlight the value of psychobiographical training to psychology students and present avenues and models for incorporating psychobiography into psychology curriculums. PMID:27247670

  13. The earliest recorded aurora in North America since European colonization [rapid communication

    Science.gov (United States)

    Silverman, S. M.

    2005-05-01

    Jesuit missionaries in the seventeenth century, in what is now Quebec, Canada and New England, United States, periodically sent reports on their activities to their superiors in Canada and France. These were then edited and published in annual volumes. A translation of these reports, together with related documents, was published in the United States around the turn of the twentieth century. Included in these volumes are three reports easily identified as auroras. The earliest of these, from 1611, predates the hitherto known first North American report, in 1719, by more than a century. The other reports are from Quebec in 1662 and mid-America in 1736. These reports are quoted in full and discussed in terms of the geophysical context of the times. Additional reports from New England for the aurora of 1719, not previously available in the auroral literature, are also presented and discussed.

  14. Examining historical and current mixed-severity fire regimes in ponderosa pine and mixed-conifer forests of western North America.

    Directory of Open Access Journals (Sweden)

    Dennis C Odion

    Full Text Available There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of historical fire regimes in the ponderosa pine and mixed-conifer forests of western North America is therefore needed to define reference conditions and help maintain characteristic ecological diversity of these systems. We compiled landscape-scale evidence of historical fire severity patterns in the ponderosa pine and mixed-conifer forests from published literature sources and stand ages available from the Forest Inventory and Analysis program in the USA. The consensus from this evidence is that the traditional reference conditions of low-severity fire regimes are inaccurate for most forests of western North America. Instead, most forests appear to have been characterized by mixed-severity fire that included ecologically significant amounts of weather-driven, high-severity fire. Diverse forests in different stages of succession, with a high proportion in relatively young stages, occurred prior to fire exclusion. Over the past century, successional diversity created by fire decreased. Our findings suggest that ecological management goals that incorporate successional diversity created by fire may support characteristic biodiversity, whereas current attempts to "restore" forests to open, low-severity fire conditions may not align with historical reference conditions in

  15. The influence of atmospheric blocking on extreme winter minimum temperatures in North America

    Science.gov (United States)

    Whan, Kirien; Zwiers, Francis; Sillmann, Jana

    2016-04-01

    Regional climate models (RCMs) are the primary source of high-resolution climate projections and it is of crucial importance to evaluate their ability to simulate extreme events under current climate conditions. Many extreme events are influenced by circulation features that occur outside, or on the edges of, RCM domains. Thus it is of interest to know whether such dynamically controlled aspects of extremes are well represented by RCMs. This study assesses the relationship between upstream blocking and cold temperature extremes over North America in observations, reanalysis products (ERA-Interim, NARR) and RCMs (CanRCM4, CRCM5, HIRHAM5, RCA4). Generalized extreme value distributions were fitted to winter minimum temperature (TNn) incorporating blocking frequency (BF) as a covariate, which has a significant influence on TNn. The magnitude of blocking influence in the RCMs is consistent with observations but the spatial extent varies. CRCM5 and HIRHAM5 reproduce the pattern of influence best compared to observations. CanRCM4 and RCA4 capture the influence of blocking in British Columbia and the northeastern United States but the extension of influence that is seen in observations and reanalysis, into the southern United States is not evident. The difference in the 20-year return value (20RV) of TNn between high and low BF indicates that blocking is associated with a decrease of up to 15°C in the 20RV over the majority of the United States and in western Canada. In northern North America the difference in the 20RV is positive as blocking is associated with warmer temperatures. The 20RVs are generally simulated well by the RCMs.

  16. Volcano-induced regime shifts in millennial tree-ring chronologies from northeastern North America.

    Science.gov (United States)

    Gennaretti, Fabio; Arseneault, Dominique; Nicault, Antoine; Perreault, Luc; Bégin, Yves

    2014-07-15

    Dated records of ice-cap growth from Arctic Canada recently suggested that a succession of strong volcanic eruptions forced an abrupt onset of the Little Ice Age between A.D. 1275 and 1300 [Miller GH, et al. (2012) Geophys Res Lett 39(2):L02708, 10.1029/2011GL050168]. Although this idea is supported by simulation experiments with general circulation models, additional support from field data are limited. In particular, the Northern Hemisphere network of temperature-sensitive millennial tree-ring chronologies, which principally comprises Eurasian sites, suggests that the strongest eruptions only caused cooling episodes lasting less than about 10 y. Here we present a new network of millennial tree-ring chronologies from the taiga of northeastern North America, which fills a wide gap in the network of the Northern Hemisphere's chronologies suitable for temperature reconstructions and supports the hypothesis that volcanoes triggered both the onset and the coldest episode of the Little Ice Age. Following the well-expressed Medieval Climate Anomaly (approximately A.D. 910-1257), which comprised the warmest decades of the last millennium, our tree-ring-based temperature reconstruction displays an abrupt regime shift toward lower average summer temperatures precisely coinciding with a series of 13th century eruptions centered around the 1257 Samalas event and closely preceding ice-cap expansion in Arctic Canada. Furthermore, the successive 1809 (unknown volcano) and 1815 (Tambora) eruptions triggered a subsequent shift to the coldest 40-y period of the last 1100 y. These results confirm that series of large eruptions may cause region-specific regime shifts in the climate system and that the climate of northeastern North America is especially sensitive to volcanic forcing. PMID:24982132

  17. Hg concentrations in fish from coastal waters of California and Western North America.

    Science.gov (United States)

    Davis, J A; Ross, J R M; Bezalel, S; Sim, L; Bonnema, A; Ichikawa, G; Heim, W A; Schiff, K; Eagles-Smith, C A; Ackerman, J T

    2016-10-15

    The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3μg/gwet weight (ww), and 10 locations an average above 1.0μg/gww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on Hg and other contaminants in coastal fish. An assessment of the raw data from these databases suggested the presence of relatively high concentrations along the California coast and in Puget Sound, and relatively low concentrations along the coasts of Alaska and Oregon, and the outer coast of Washington. The dataset suggests that Hg concentrations of public health concern can be observed at any location on the coast of Western North America where long-lived predator species are sampled. Output from a linear mixed-effects model resembled the spatial pattern observed for the raw data and suggested, based on the limited dataset, a lack of trend in fish Hg over the nearly 30-year period covered by the dataset. Expanded and continued monitoring, accompanied by rigorous data management procedures, would be of great value in characterizing methylHg exposure, and tracking changes in contamination of coastal fish in response to possible increases in atmospheric Hg emissions in Asia, climate change, and terrestrial Hg control efforts in coastal watersheds. PMID:27067833

  18. Objective calibration of regional climate models: Application over Europe and North America

    Science.gov (United States)

    Bellprat, O.; de Elía, R.; Frigon, A.; Kotlarski, S.; Lüthi, D.; Laprise, R.; Schär, C.

    2014-12-01

    An important source of model uncertainty in climate models arises from unconfined model parameters in physical parameterizations. These parameters are commonly estimated on the basis of manual adjustments (expert tuning), which carries the risk of over-tuning the parameters for a specific climate region or time period. This issue is particularly germane in the case of regional climate models (RCM), which are often developed and used in one or a few geographical regions only. Here we address the role of objective parameter calibration in this context. Using a previously developed objective calibration methodology, we calibrate an RCM over two regions (Europe and North America) and investigate the transferability of the results. A total of eight different model parameters are calibrated, using a metamodel to account for parameter interactions. We demonstrate that the calibration is effective in reducing model biases in both domains. For Europe, this concerns in particular a pronounced reduction of the summer warm bias and the associated overestimation of interannual temperature variability, that has persisted previous expert tuning efforts and that is common in many global and regional climate models. The key process responsible behind this improvement is an increased hydrological conductivity. Over North America, there is also some reduction of the summer warm bias, but in addition the calibration achieves a pronounced reduction of winter biases in interannual temperature variability. We also find that the calibrated parameter values are almost identical for both domains, i.e. the parameter calibration is transferable between the two regions. This is a promising result and indicates that models may be more universal than previously considered.

  19. Consistency Between Sun-Induced Chlorophyll Fluorescence and Gross Primary Production of Vegetation in North America

    Science.gov (United States)

    Zhang, Yao; Xiao, Xiangming; Jin, Cui; Dong, Jinwei; Zhou, Sha; Wagle, Pradeep; Joiner, Joanna; Guanter, Luis; Zhang, Yongguang; Zhang , Geli; Qin, Yuanwei; Wang, Jie; Moore, Berrien, III

    2016-01-01

    Accurate estimation of the gross primary production (GPP) of terrestrial ecosystems is vital for a better understanding of the spatial-temporal patterns of the global carbon cycle. In this study,we estimate GPP in North America (NA) using the satellite-based Vegetation Photosynthesis Model (VPM), MODIS (Moderate Resolution Imaging Spectrometer) images at 8-day temporal and 500 meter spatial resolutions, and NCEP-NARR (National Center for Environmental Prediction-North America Regional Reanalysis) climate data. The simulated GPP (GPP (sub VPM)) agrees well with the flux tower derived GPP (GPPEC) at 39 AmeriFlux sites (155 site-years). The GPP (sub VPM) in 2010 is spatially aggregated to 0.5 by 0.5-degree grid cells and then compared with sun-induced chlorophyll fluorescence (SIF) data from Global Ozone Monitoring Instrument 2 (GOME-2), which is directly related to vegetation photosynthesis. Spatial distribution and seasonal dynamics of GPP (sub VPM) and GOME-2 SIF show good consistency. At the biome scale, GPP (sub VPM) and SIF shows strong linear relationships (R (sup 2) is greater than 0.95) and small variations in regression slopes ((4.60-5.55 grams Carbon per square meter per day) divided by (milliwatts per square meter per nanometer per square radian)). The total annual GPP (sub VPM) in NA in 2010 is approximately 13.53 petagrams Carbon per year, which accounts for approximately 11.0 percent of the global terrestrial GPP and is within the range of annual GPP estimates from six other process-based and data-driven models (11.35-22.23 petagrams Carbon per year). Among the seven models, some models did not capture the spatial pattern of GOME-2 SIF data at annual scale, especially in Midwest cropland region. The results from this study demonstrate the reliable performance of VPM at the continental scale, and the potential of SIF data being used as a benchmark to compare with GPP models.

  20. The spatially varying influence of humans on fire probability in North America

    Science.gov (United States)

    Parisien, Marc-André; Miller, Carol; Parks, Sean A.; DeLancey, Evan R.; Robinne, François-Nicolas; Flannigan, Mike D.

    2016-07-01

    Humans affect fire regimes by providing ignition sources in some cases, suppressing wildfires in others, and altering natural vegetation in ways that may either promote or limit fire. In North America, several studies have evaluated the effects of society on fire activity; however, most studies have been regional or subcontinental in scope and used different data and methods, thereby making continent-wide comparisons difficult. We circumvent these challenges by investigating the broad-scale impact of humans on fire activity using parallel statistical models of fire probability from 1984 to 2014 as a function of climate, enduring features (topography and percent nonfuel), lightning, and three indices of human activity (population density, an integrated metric of human activity [Human Footprint Index], and a measure of remoteness [roadless volume]) across equally spaced regions of the United States and Canada. Through a statistical control approach, whereby we account for the effect of other explanatory variables, we found evidence of non-negligible human–wildfire association across the entire continent, even in the most sparsely populated areas. A surprisingly coherent negative relationship between fire activity and humans was observed across the United States and Canada: fire probability generally diminishes with increasing human influence. Intriguing exceptions to this relationship are the continent’s least disturbed areas, where fewer humans equate to less fire. These remote areas, however, also often have lower lightning densities, leading us to believe that they may be ignition limited at the spatiotemporal scale of the study. Our results suggest that there are few purely natural fire regimes in North America today. Consequently, projections of future fire activity should consider human impacts on fire regimes to ensure sound adaptation and mitigation measures in fire-prone areas.

  1. Hg concentrations in fish from coastal waters of California and Western North America

    Science.gov (United States)

    Davis, Jay; Ross, John; Bezalel, Shira; Sim, Lawrence; Bonnema, Autumn; Ichikawa, Gary; Heim, Wes; Schiff, Kenneth C; Eagles-Smith, Collin A.; Ackerman, Josh

    2016-01-01

    The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3 μg/g wet weight (ww), and 10 locations an average above 1.0 μg/g ww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on Hg and other contaminants in coastal fish. An assessment of the raw data from these databases suggested the presence of relatively high concentrations along the California coast and in Puget Sound, and relatively low concentrations along the coasts of Alaska and Oregon, and the outer coast of Washington. The dataset suggests that Hg concentrations of public health concern can be observed at any location on the coast of Western North America where long-lived predator species are sampled. Output from a linear mixed-effects model resembled the spatial pattern observed for the raw data and suggested, based on the limited dataset, a lack of trend in fish Hg over the nearly 30-year period covered by the dataset. Expanded and continued monitoring, accompanied by rigorous data management procedures, would be of great value in characterizing methylHg exposure, and tracking changes in contamination of coastal fish in response to possible increases in atmospheric Hg emissions in Asia, climate change, and terrestrial Hg control efforts in coastal watersheds.

  2. Seismic hazard map of North and Central America and the Caribbean

    Directory of Open Access Journals (Sweden)

    K. M. Shedlock

    1999-06-01

    Full Text Available Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. National, state, and local governments, decision makers, engineers, planners, emergency response organizations, builders, universities, and the general public require seismic hazard estimates for land use planning, improved building design and construction (including adoption of building construction codes, emergency response preparedness plans, economic forecasts, housing and employment decisions, and many more types of risk mitigation. The seismic hazard map of North and Central America and the Caribbean is the concatenation of various national and regional maps, involving a suite of approaches. The combined maps and documentation provide a useful regional seismic hazard framework and serve as a resource for any national or regional agency for further detailed studies applicable to their needs. This seismic hazard map depicts Peak Ground Acceleration (PGA with a 10% chance of exceedance in 50 years. PGA, a short-period ground motion parameter that is proportional to force, is the most commonly mapped ground motion parameter because current building codes that include seismic provisions specify the horizontal force a building should be able to withstand during an earthquake. This seismic hazard map of North and Central America and the Caribbean depicts the likely level of short-period ground motion from earthquakes in a fifty-year window. Short-period ground motions effect short-period structures (e.g., one-to-two story buildings. The highest seismic hazard values in the region generally occur in areas that have been, or are likely to be, the sites of the largest plate boundary earthquakes.

  3. Trends in incidence and prognosis of the histological subtypes of lung cancer in North America, Australia, New Zealand and Europe

    NARCIS (Netherlands)

    M.L.G. Janssen-Heijnen (Maryska); J.W.W. Coebergh (Jan Willem)

    2001-01-01

    textabstractBackground: Since the incidence of the histological subtypes of lung cancer in industrialised countries has changed dramatically over the last two decades, we reviewed trends in the incidence and prognosis in North America, Australia, New Zealand and Europe, according to period of diagno

  4. Comparing emission inventories and model-ready emission datasets between Europe and North America for the AQMEII project

    NARCIS (Netherlands)

    Pouliot, G.; Pierce, T.; Denier van der Gon, H.; Schaap, M.; Moran, M.; Nopmongcol, U.

    2012-01-01

    This paper highlights the similarities and differences in how emission inventories and datasets were developed and processed across North America and Europe for the Air Quality Model Evaluation International Initiative (AQMEII) project and then characterizes the emissions for the two domains. We foc

  5. CO2 uptake and ecophysiological parameters of the grain crops of midcontinent North America: estimates from flux tower measurements

    Science.gov (United States)

    We present net CO2 exchange data from 13 flux tower sites with 27 site-years of measurements over maize and wheat fields across midcontinent North America. A numerically robust “light-soil temperature-VPD”-based method was used to partition the data into photosynthetic assimilation and ecosystem re...

  6. 77 FR 45596 - Shell Energy North America (US), L.P. v. California Independent System Operator Corporation...

    Science.gov (United States)

    2012-08-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Shell Energy North America (US), L.P. v. California Independent System... Federal Energy Regulatory Commission's (Commission) Rules of Practice and Procedure, 18 CFR 385.206,...

  7. Cladosporium herbarum is a cause of a leaf spot disease on Caltha leptosepala (marsh-marigold) in western North America

    Science.gov (United States)

    Caltha leptosepala ssp. howellii and Caltha leptosepala ssp. leptosepala (marsh-marigold, Ranunculaceae) inhabit stream banks and wet meadows in subalpine zones in the northern Rocky and Cascade mountain ranges of North America. Cladosporium herbarum (anamorphic Davidiellaceae) is a cosmopolitan sap...

  8. 75 FR 8921 - Grant of Authority for Subzone Status; Brightpoint North America L.P. (Cell Phone Kitting and...

    Science.gov (United States)

    2010-02-26

    ... kitting and distribution of cell phones at the facilities of Brightpoint North America L.P., located in... authority to establish a special-purpose subzone at the cell phone kitting and distribution facilities of...); Whereas, notice inviting public comment has been given in the Federal Register (74 FR 37689-37690, July...

  9. Sex pheromone component ratios and mating isolation among three lygus plant-bug species of North America

    Science.gov (United States)

    Three species of Lygus (Hemiptera: Miridae), L. hesperus, L. lineolaris, and L. elisus are major pests of many agricultural crops in North America. Previous studies have shown males and females contain µg amounts of (E)-4-oxo-2-hexenal, hexyl butyrate, and (E)-2-hexenyl butyrate, and the volatiles a...

  10. LETHALITY OF PSEUDOMONAS FLUORESCENS STRAIN CLO145A TO THE 2 ZEBRA MUSSEL SPECIES PRESENT IN NORTH AMERICA

    International Nuclear Information System (INIS)

    These experiments indicated that bacterial strain CL0145A of Pseudomonas fluorescens is equally lethal to the 2 zebra mussel species present in North America, Dreissena polymorpha and Dreissena bugensis. Thus, this bacterial strain should be equally effective at killing zebra mussels in power plant pipes, irrespective of which species is present

  11. 76 FR 61401 - Atomic Safety and Licensing Board; In the Matter of Nuclear Innovation North America LLC (South...

    Science.gov (United States)

    2011-10-04

    ... Texas Project Units 3 and 4); Evidentiary Hearing to Receive Testimony and Exhibits Regarding the... receive testimony and exhibits regarding the application of Nuclear Innovation North America LLC (NINA... Staff--hearing this contention in August 2011 because Intervenors' expert witness was unavailable as...

  12. 77 FR 43122 - Corob North America, a Subsidiary of CPS Color Equipment, Inc., Including On-Site Leased Workes...

    Science.gov (United States)

    2012-07-23

    ... insurance (UI) tax account under the name CPS Color Equipment, Inc. The amended notice applicable to TA-W-81... Employment and Training Administration Corob North America, a Subsidiary of CPS Color Equipment, Inc... Eligibility to Apply for Worker Adjustment Assistance on January 27, 2012, applicable to workers of CPS...

  13. A dated phylogeny of the palm tribe Chamaedoreeae supports Eocene dispersal between Africa, North and South America

    DEFF Research Database (Denmark)

    Cuenca-Navarro, Argelia; Lange, Conny Bruun Asmussen; Borchsenius, Finn

    2008-01-01

    The palm tribe Chamaedoreeae reaches its higher diversity in Central America, however, its distribution ranges from the north eastern part of Mexico to Bolivia with a disjunction to the Mascarene Islands in the Indian Ocean. The disjunct distribution of Chamaedoreeae is generally considered a res...

  14. 78 FR 15718 - Iberdrola Renewables, Inc. PacifiCorp NextEra Energy Resources, LLC Invenergy Wind North America...

    Science.gov (United States)

    2013-03-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Iberdrola Renewables, Inc. PacifiCorp NextEra Energy Resources, LLC Invenergy Wind North America LLC Horizon Wind Energy LLC v. Bonneville Power Administration; Notice...

  15. 76 FR 29797 - International Automotive Components, North America, Including On-Site Leased Workers From At-Work...

    Science.gov (United States)

    2011-05-23

    ... notice was published in the Federal Register on April 22, 2011 (76 FR 22732). At the request of the State... Federal Register on February 23, 2009 (74 FR 8115). In order to avoid an overlap in worker group coverage... Employment and Training Administration International Automotive Components, North America, Including On-...

  16. Transmission patterns of smallpox: Systematic review of natural outbreaks in Europe and North America since World War II

    NARCIS (Netherlands)

    V. Bhatnagar (Vibha); M.A. Stoto (Michael); S.C. Morton (Sally); R. Boer (Rob); S.A. Bozzette (Samuel)

    2006-01-01

    textabstractBackground: Because smallpox (variola major) may be used as a biological weapon, we reviewed outbreaks in post-World War II Europe and North America in order to understand smallpox transmission patterns. Methods: A systematic review was used to identify papers from the National Library o

  17. Neogene north American-Caribbean plate boundary across Northern Central America: Offset along the polochic fault

    Science.gov (United States)

    Burkart, Burke

    1983-12-01

    The Polochic fault was a segment of the North American-Caribbean plate boundary across Central America in the Neogene. Its 130 km of left slip was previously determined by matching structures and stratigraphie outcrop patterns of northwest and central Guatemala across the fault. Additional support for the model and the youthfulness of the recorded offset comes from an essentially perfect match of major geomorphic features across the fault. A reconstruction process which eliminates 123 km of left slip brings together rivers and drainage divides that existed before the Polochic became active. With the reconstruction carried across the isthmus on an east-west fault the regional structural geology assumes the coherent pattern of a continuous orogenic belt whose geometry is compatible with the model of collisional tectonics centered on the Motagua "suture zone". Confined within this belt, narrowed to some 60 km by the reconstruction, lie the major Laramide thrusts, folds and tectonically emplaced serpentinites of Guatemala. Crystalline rocks of Guatemala re-join the Chiapas Massif and Paleozoic sedimentary rocks, exposed in the core of an almost-continuous anticlinorium, extend from southern Chiapas to Lake Izabal. The Polochic does not bend in eastern Guatemala but continues eastward to the Motagua fault where it dies. Westward drift of the northern block resulted in rifting which extended from eastern Guatemala into the Caribbean along the Cayman trough. The Honduras depression may represent an element of a triple junction along with the Polochic and Izabal-Cayman rift. The Polochic continues westward into the Pacific Ocean and offsets the Middle America trench. The Polochic has offset the Miocene volcanic belt of northern Central America, confirming the previous estimate of a Neogene time of movement. About 300 km of relative east-west Neogene displacement has been recorded on the Mid-Cayman rise, only 130 km of which can be accounted for across the Polochic. It is

  18. Late Pliocene Glyptodontinae (Xenarthra, Cingulata, Glyptodontidae) of South and North America: Morphology and paleobiogeographical implications in the GABI

    Science.gov (United States)

    Zurita, Alfredo E.; Carlini, Alfredo A.; Gillette, David; Sánchez, Rodolfo

    2011-03-01

    Knowledge of the main aspects of the Great American Biotic Interchange (GABI) concerning the glyptodontine Glyptodontidae (Xenarthra) is very scarce. A bidirectional dispersal process was recently proposed for this clade, with the presence of the North American genus Glyptotherium Osborn recognized in latest Pleistocene sediments of northern South America (Venezuela and Brazil). However, the earliest stages of this paleobiogeographical process remain poorly understood, mainly because of the limited fossil record on this clade in late Pliocene sediments. The goals of this contribution are: a) to present and describe the first record of a glyptodontine glyptodontid from the late Pliocene of northern South America, tentatively assigned to a new species of Boreostemma Carlini et al. ( Boreostemma? sp. nov); and b) to analyze its paleobiogeographical implications with respect to the GABI. This new material was recovered from the San Gregorio Formation (late Pliocene, prior the GABI) in northern Venezuela, where it is represented by several osteoderms of the dorsal carapace. A comparison among the three known late Pliocene glyptodontine glyptodontids of a) southern South America ( Paraglyptodon), b) northern South America ( Boreostemma), and c) southern North America (" Glyptotherium"), reveals a series of shared characters between (b) and (c), not present in (a). The most important of these shared characters in (b) and (c) are: all the osteoderms present a great development of the central figure, which is always larger than the peripherals; the sulcus that delimits the central and peripheral figures is narrower and shallower; and all the osteoderms present are relatively thin. This evidence suggests that the lineage of Glyptodontinae which participated in the GABI and subsequently diversified in North America originated in northern South America. Moreover, the evident morphological differences between these glyptodontines with respect to the southern South American

  19. Potential effects of climate change on aquatic ecosystems of the Great Plains of North America

    Science.gov (United States)

    Covich, A.P.; Fritz, S.C.; Lamb, P.J.; Marzolf, R.D.; Matthews, W.J.; Poiani, K.A.; Prepas, E.E.; Richman, M.B.; Winter, T.C.

    1997-01-01

    The Great Plains landscape is less topographically complex than most other regions within North America, but diverse aquatic ecosystems, such as playas, pothole lakes, ox-bow lakes, springs, groundwater aquifers, intermittent and ephemeral streams, as well as large rivers and wetlands, are highly dynamic and responsive to extreme climatic fluctuations. We review the evidence for climatic change that demonstrates the historical importance of extremes in north-south differences in summer temperatures and east-west differences in aridity across four large subregions. These physical driving forces alter density stratification, deoxygenation, decomposition and salinity. Biotic community composition and associated ecosystem processes of productivity and nutrient cycling respond rapidly to these climatically driven dynamics. Ecosystem processes also respond to cultural effects such as dams and diversions of water for irrigation, waste dilution and urban demands for drinking water and industrial uses. Distinguishing climatic from cultural effects in future models of aquatic ecosystem functioning will require more refinement in both climatic and economic forecasting. There is a need, for example, to predict how long-term climatic forecasts (based on both ENSO and global warming simulations) relate to the permanence and productivity of shallow water ecosystems. Aquatic ecologists, hydrologists, climatologists and geographers have much to discuss regarding the synthesis of available data and the design of future interdisciplinary research. ?? 1997 by John Wiley & Sons, Ltd.

  20. Carbon consequences of the turn-of-the-century drought in North America

    Science.gov (United States)

    Schwalm, C. R.; Williams, C. A.; Schaefer, K. M.; Baldocchi, D. D.; Black, T. A.; Goldstein, A. H.; Law, B. E.; Oechel, W. C.; Paw U, K.; Scott, R. L.; Ghimire, B.

    2012-12-01

    From 2000 to 2004 the western portion of North America experienced a severe drought. This event was truly extreme, not only relative to the climate of recent decades but also when compared to climate reconstructed over the past 1000 years. These longer-term tree-ring records indicate that this 5-year drought was the most severe region-wide event of its kind in the past 800 years. The far reaching consequences of this turn of the century drought event were shown by decreased runoff in all major river basins of the western US, depressed crop yields, increases in burned area and direct fire emissions, and a substantial decline in the carbon uptake by the terrestrial biosphere. Net carbon uptake was reduced by an average of about 50% over the western region, with large subregional variation and larger impacts on evergreen needleleaf forests. Future changes in precipitation and drought, based on IPCC AR5 projections, indicate that drought events of this length and severity will be commonplace through the end of the 21st century, and suggest the 2000-2004 drought is representative of the wet end of the drier hydroclimatic period in the latter half of the 21th century. This could lead to increased mortality of sensitive plant species, as observed in parts of the western region. Furthermore, a multi-decadal period of dryness would effectively disable the weak sink in western North American and is consistent with a new megadrought.

  1. Conditions for the spread of the Peyote cult in North America

    Directory of Open Access Journals (Sweden)

    Åke Hultkrantz

    1975-01-01

    Full Text Available As is well known large parts of native North America with the Prairies and Plains in the middle of the continent as the centre of diffusion have constituted, since the end of the last century, the scene of a nativistic Indian movement, the so-called peyote cult. The peyote cult—or, as it should have been called, the peyote religion — is named after its central cultic action, the consumption (by eating, drinking or smoking of the spineless cactus peyote (Lophophora williamsii. This cactus that may be found growing wild along the Rio Grande and in the country south of this river contains several alkaloids, among them the morphine-like, hallucinogeneous mescaline. In pre-Columbian days peyote was used in connection with certain public ceremonies among the Indians of Mexico, for instance, at the annual thanksgiving ceremonies. In its modern form the peyote ritual constitutes a religious complex of its own, considered to promote health, happiness and welfare among its adepts. The two major questions are: what were the conditions for the diffusion of the peyote cult? What particular factors accounted for the spread of the cult to just those areas that were mentioned above, and for its obstruction in other areas? The change in the North American Indian situation at the end of the nineteenth century supplied new facilities for religious innovations and for the introduction of a foreign religious movement, the peyote cult.

  2. Sources of carbon monoxide and formaldehyde in North America determined from high-resolution atmospheric data

    Directory of Open Access Journals (Sweden)

    S. M. Miller

    2008-06-01

    Full Text Available We analyze the North American budget for carbon monoxide using data for CO and formaldehyde concentrations from tall towers and aircraft in a model-data assimilation framework. The Stochastic Time-Inverted, Lagrangian Transport model for CO (STILT-CO determines local to regional-scale CO contributions associated with production from fossil fuel combustion, biomass burning, and oxidation of volatile organic compounds (VOCs using an ensemble of Lagrangian particles driven by high resolution assimilated meteorology. In most cases, the model demonstrates high fidelity simulations of hourly surface data from tall towers and point measurements from aircraft, with somewhat less satisfactory performance in coastal regions and when CO from large biomass fires in Alaska and the Yukon Territory influence the continental US.

    Inversions of STILT-CO simulations for CO and formaldehyde show that current inventories of CO emissions from fossil fuel combustion are significantly too high, by almost a factor of three in summer and a factor two in early spring, consistent with recent analyses of data from the INTEX-A aircraft program. Formaldehyde data help to show that sources of CO from oxidation of CH4 and other VOCs represent the dominant sources of CO over North America in summer.

  3. Antigenic Characterization of H3 Subtypes of Avian Influenza A Viruses from North America.

    Science.gov (United States)

    Bailey, Elizabeth; Long, Li-Ping; Zhao, Nan; Hall, Jeffrey S; Baroch, John A; Nolting, Jacqueline; Senter, Lucy; Cunningham, Frederick L; Pharr, G Todd; Hanson, Larry; Slemons, Richard; DeLiberto, Thomas J; Wan, Xiu-Feng

    2016-05-01

    Besides humans, H3 subtypes of influenza A viruses (IAVs) can infect various animal hosts, including avian, swine, equine, canine, and sea mammal species. These H3 viruses are both antigenically and genetically diverse. Here, we characterized the antigenic diversity of contemporary H3 avian IAVs recovered from migratory birds in North America. Hemagglutination inhibition (HI) assays were performed on 37 H3 isolates of avian IAVs recovered from 2007 to 2011 using generated reference chicken sera. These isolates were recovered from samples taken in the Atlantic, Mississippi, Central, and Pacific waterfowl migration flyways. Antisera to all the tested H3 isolates cross-reacted with each other and, to a lesser extent, with those to H3 canine and H3 equine IAVs. Antigenic cartography showed that the largest antigenic distance among the 37 avian IAVs is about four units, and each unit corresponds to a 2 log 2 difference in the HI titer. However, none of the tested H3 IAVs cross-reacted with ferret sera derived from contemporary swine and human IAVs. Our results showed that the H3 avian IAVs we tested lacked significant antigenic diversity, and these viruses were antigenically different from those circulating in swine and human populations. This suggests that H3 avian IAVs in North American waterfowl are antigenically relatively stable. PMID:27309078

  4. Antigenic characterization of H3 subtypes of avian influenza A viruses from North America

    Science.gov (United States)

    Bailey, Elizabeth; Long, Li-Pong; Zhao, Nan; Hall, Jeffrey S.; Baroch, John A; Nolting, Jaqueline; Senter, Lucy; Cunningham, Frederick L; Pharr, G Todd; Hanson, Larry; Slemons, Richard; DeLiberto, Thomas J.; Wan, Xiu-Feng

    2016-01-01

    Besides humans, H3 subtypes of influenza A viruses (IAVs) can infect various animal hosts, including avian, swine, equine, canine, and sea mammal species. These H3 viruses are both antigenically and genetically diverse. Here, we characterized the antigenic diversity of contemporary H3 avian IAVs recovered from migratory birds in North America. Hemagglutination inhibition (HI) assays were performed on 37 H3 isolates of avian IAVs recovered from 2007 to 2011 using generated reference chicken sera. These isolates were recovered from samples taken in the Atlantic, Mississippi, Central, and Pacific waterfowl migration flyways. Antisera to all the tested H3 isolates cross-reacted with each other and, to a lesser extent, with those to H3 canine and H3 equine IAVs. Antigenic cartography showed that the largest antigenic distance among the 37 avian IAVs is about four units, and each unit corresponds to a 2 log 2 difference in the HI titer. However, none of the tested H3 IAVs cross-reacted with ferret sera derived from contemporary swine and human IAVs. Our results showed that the H3 avian IAVs we tested lacked significant antigenic diversity, and these viruses were antigenically different from those circulating in swine and human populations. This suggests that H3 avian IAVs in North American waterfowl are antigenically relatively stable.

  5. The structure of Holocene climate change in mid-latitude North America

    Science.gov (United States)

    Shuman, Bryan N.; Marsicek, Jeremiah

    2016-06-01

    A sequence of long-term and rapid changes during the Holocene appears in a network of 40 well-resolved paleoclimate datasets from mid-latitude North America, including records of pollen-inferred temperatures, alkenone-derived sea-surface temperatures (SSTs), lake-level changes, dust accumulation, and lake isotopes from Idaho to Maine. Statistical analyses reveal that changes in insolation and the Laurentide Ice Sheet explain 51.7% of the variance in the records, especially multi-millennial trends, but peak rates of change indicate additional rapid changes at ca. 10.8, 9.4, 8.3, 7.0, 5.5-5.2, 4.7, 2.1, and 0.9 ka. Step changes between 9.4 and 8.3 ka relate to ice sheet dynamics that warmed much of the region, and changes at 5.5 ka were the largest since the demise of the ice sheet. The shift at 5.5 ka initiated widespread cooling and increases in effective moisture, which culminated in the coolest, wettest millennia in most areas after 2.1 ka. Replicated evidence from multiple records also shows a spatially-varied set of multi-century fluctuations including 1) low temperatures and high effective moisture at 5.5-4.8 ka in the mid-continent and 2) repeated phases of low SSTs, cool summers, and drought superimposed upon long cooling, moistening trends in eastern North American since 5.5 ka.

  6. Using climate, energy, and spatial-based hypotheses to interpret macroecological patterns of North America chelonians

    Science.gov (United States)

    Ennen, Joshua R.; Agha, Mickey; Matamoros, Wilfredo A.; Hazzard, Sarah C.; Lovich, Jeffrey E.

    2016-01-01

    Our study investigates how factors, such as latitude, productivity, and several environmental variables, influence contemporary patterns of the species richness in North American turtles. In particular, we test several hypotheses explaining broad-scale species richness patterns on several species richness data sets: (i) total turtles, (ii) freshwater turtles only, (iii) aquatic turtles, (iv) terrestrial turtles only, (v) Emydidae, and (vi) Kinosternidae. In addition to spatial data, we used a combination of 25 abiotic variables in spatial regression models to predict species richness patterns. Our results provide support for multiple hypotheses related to broad-scale patterns of species richness, and in particular, hypotheses related to climate, productivity, water availability, topography, and latitude. In general, species richness patterns were positively associated with temperature, precipitation, diversity of streams, coefficient of variation of elevation, and net primary productivity. We also found that North America turtles follow the general latitudinal diversity gradient pattern (i.e., increasing species richness towards equator) by exhibiting a negative association with latitude. Because of the incongruent results among our six data sets, our study highlights the importance of considering phylogenetic constraints and guilds when interpreting species richness patterns, especially for taxonomic groups that occupy a myriad of habitats.

  7. Antigenic Characterization of H3 Subtypes of Avian Influenza A Viruses from North America

    Science.gov (United States)

    Bailey, Elizabeth; Long, Li-Ping; Zhao, Nan; Hall, Jeffrey S.; Baroch, John A.; Nolting, Jacqueline; Senter, Lucy; Cunningham, Frederick L.; Pharr, G. Todd; Hanson, Larry; Slemons, Richard; DeLiberto, Thomas J.; Wan, Xiu-Feng

    2016-01-01

    SUMMARY Besides humans, H3 subtypes of influenza A viruses (IAVs) can infect various animal hosts including avian, swine, equine, canine, and sea mammals. These H3 viruses are both antigenically and genetically diverse. Here we characterized the antigenic diversity of contemporary H3 avian IAVs recovered from migratory birds in North America. Hemagglutination inhibition (HI) assays were performed on 37 H3 isolates of avian IAVs recovered from 2007 to 2011 using generated reference chicken sera. These isolates were recovered from samples taken in the Atlantic, Mississippi, Central, and Pacific waterfowl migration flyways. Antisera to all the tested H3 isolates cross-reacted with each other, and, to a lesser extent, with those to H3 canine and H3 equine IAVs. Antigenic cartography showed that the largest antigenic distance among the 37 avian IAVs is about 4 units, and each unit corresponds to a 2log2 difference in the HI titer. However, none of the tested H3 IAVs cross-reacted with ferret sera derived from contemporary swine and human IAVs. Our results showed that the H3 avian IAVs we tested lacked significant antigenic diversity, and these viruses were antigenically different from those circulating in swine and human populations. This suggests that H3 avian IAVs in North American waterfowl are antigenically relatively stable. PMID:27309078

  8. No major stratigraphic gap exists near the Middle-Upper Pennsylvanian (Desmoinesian-Missourian) boundary in North America

    Science.gov (United States)

    Falcon-Lang, H. J.; Heckel, P.H.; DiMichele, W.A.; Blake, B.M.; Easterday, C.R.; Eble, C.F.; Elrick, S.; Gastaldo, R.A.; Greb, S.F.; Martino, R.L.; John, Nelson W.; Pfefferkorn, H.W.; Phillips, T.L.; Rosscoe, S.J.

    2011-01-01

    Interregional correlation of the marine zones of major cyclothems between North America and eastern Europe does not support assertions that a major stratigraphic gap exists between the traditional regional Desmoinesian and Missourian stages in North America. Such a gap was previously proposed to explain an abrupt change in megafloral assemblages in the northern Appalachian Basin and by extension across all of North America. Conodont-based correlation from the essentially complete low-shelf Midcontinent succession (distal from the highstand shoreline), through the mid-shelf Illinois Basin, to the high shelf of the Appalachian Basin (proximal to highstand shoreline) demonstrates that all major ???400 kyr cyclothem groupings in the Midcontinent are recognizable in the Illinois Basin. In the Appalachian Basin, however, the grouping at the base of the Missourian is represented only by paleosols and localized coal. The immediately preceding grouping was removed very locally by paleovalley incision, as is evident at the 7-11 Mine, Columbiana County, Ohio, from which the original megafloral data were derived. At the few localities where incised paleodrainage exists, there may be a gap of ???1000 kyr, but a gap of no more than ???600 kyr occurs elsewhere in the Appalachian Basin at that level and its magnitude progressively decreases westward into the Illinois (???300 kyr) and Midcontinent (<200 kyr) Basins. Thus, while a gap is present near the Desmoinesian-Missourian boundary in North America, it is typically more than an order of magnitude smaller than that originally proposed and is similar to the gaps inferred at sequence boundaries between cyclothems at many horizons in the Pennsylvanian of North America. Copyright ?? 2011, SEPM.

  9. Why Don’t They Participate? A Self-Study of Chinese Graduate Students’ Classroom:Involvement in North America

    Directory of Open Access Journals (Sweden)

    Chunlei Lu

    2010-07-01

    Full Text Available China is now the world’s largest source of international students. In terms of learning performance, Chinese graduate students studying in North America exhibit distinct differences from students who are born and raised in North America. Conflicting cultural values compel Chinese students to reconcile East-West cultures, and put an onus on North American instructors to implement culturally-sensitive pedagogy. Employing the theoretic framework of yin-yang theory, this paper examines Chinese graduate students’ classroom performance against the backdrop of East-West cultural negotiation, and specifically seeks to identify which factors inhibit Chinese graduate students’ participation in North American classrooms. Drawing from their own living experiences, the authors employ self-study in the methodological form of narrative inquiry – in conjunction with references from existing literature – to investigate Chinese graduates’ classroom challenges. Results reveal six factors impacting students’ classroom performance: language; knowledge of the education system; knowledge of the social system; personality; influence of traditional culture; and social/economic/political changes. Future research directions are also suggested.Key words: Chinese graduates, East-West, cross-culture, North America, classroom involvement, self-study 

  10. RNA viral metagenome of whiteflies leads to the discovery and characterization of a whitefly-transmitted carlavirus in North America.

    Directory of Open Access Journals (Sweden)

    Karyna Rosario

    Full Text Available Whiteflies from the Bemisia tabaci species complex have the ability to transmit a large number of plant viruses and are some of the most detrimental pests in agriculture. Although whiteflies are known to transmit both DNA and RNA viruses, most of the diversity has been recorded for the former, specifically for the Begomovirus genus. This study investigated the total diversity of DNA and RNA viruses found in whiteflies collected from a single site in Florida to evaluate if there are additional, previously undetected viral types within the B. tabaci vector. Metagenomic analysis of viral DNA extracted from the whiteflies only resulted in the detection of begomoviruses. In contrast, whiteflies contained sequences similar to RNA viruses from divergent groups, with a diversity that extends beyond currently described viruses. The metagenomic analysis of whiteflies also led to the first report of a whitefly-transmitted RNA virus similar to Cowpea mild mottle virus (CpMMV Florida (genus Carlavirus in North America. Further investigation resulted in the detection of CpMMV Florida in native and cultivated plants growing near the original field site of whitefly collection and determination of its experimental host range. Analysis of complete CpMMV Florida genomes recovered from whiteflies and plants suggests that the current classification criteria for carlaviruses need to be reevaluated. Overall, metagenomic analysis supports that DNA plant viruses carried by B. tabaci are dominated by begomoviruses, whereas significantly less is known about RNA viruses present in this damaging insect vector.

  11. RNA viral metagenome of whiteflies leads to the discovery and characterization of a whitefly-transmitted carlavirus in North America.

    Science.gov (United States)

    Rosario, Karyna; Capobianco, Heather; Ng, Terry Fei Fan; Breitbart, Mya; Polston, Jane E

    2014-01-01

    Whiteflies from the Bemisia tabaci species complex have the ability to transmit a large number of plant viruses and are some of the most detrimental pests in agriculture. Although whiteflies are known to transmit both DNA and RNA viruses, most of the diversity has been recorded for the former, specifically for the Begomovirus genus. This study investigated the total diversity of DNA and RNA viruses found in whiteflies collected from a single site in Florida to evaluate if there are additional, previously undetected viral types within the B. tabaci vector. Metagenomic analysis of viral DNA extracted from the whiteflies only resulted in the detection of begomoviruses. In contrast, whiteflies contained sequences similar to RNA viruses from divergent groups, with a diversity that extends beyond currently described viruses. The metagenomic analysis of whiteflies also led to the first report of a whitefly-transmitted RNA virus similar to Cowpea mild mottle virus (CpMMV Florida) (genus Carlavirus) in North America. Further investigation resulted in the detection of CpMMV Florida in native and cultivated plants growing near the original field site of whitefly collection and determination of its experimental host range. Analysis of complete CpMMV Florida genomes recovered from whiteflies and plants suggests that the current classification criteria for carlaviruses need to be reevaluated. Overall, metagenomic analysis supports that DNA plant viruses carried by B. tabaci are dominated by begomoviruses, whereas significantly less is known about RNA viruses present in this damaging insect vector.

  12. A visual identification key utilizing both gestalt and analytic approaches to identification of Carices present in North America (Plantae, Cyperaceae).

    Science.gov (United States)

    Jones, Timothy Mark

    2013-01-01

    Images are a critical part of the identification process because they enable direct, immediate and relatively unmediated comparisons between a specimen being identified and one or more reference specimens. The Carices Interactive Visual Identification Key (CIVIK) is a novel tool for identification of North American Carex species, the largest vascular plant genus in North America, and two less numerous closely-related genera, Cymophyllus and Kobresia. CIVIK incorporates 1288 high-resolution tiled image sets that allow users to zoom in to view minute structures that are crucial at times for identification in these genera. Morphological data are derived from the earlier Carex Interactive Identification Key (CIIK) which in turn used data from the Flora of North America treatments. In this new iteration, images can be viewed in a grid or histogram format, allowing multiple representations of data. In both formats the images are fully zoomable.

  13. Comparative Study of Basins within Palaeogene Seaway in East China and Cretaceous Seaway in North America and Its Reservoir Significance

    Institute of Scientific and Technical Information of China (English)

    Wu Xiantao

    2007-01-01

    The well known Cretaceous seaway in North America was recognized in the middle of the last century and the Palaeogene seaway in East China was proposed by the author recently. The two seaways located on the opposite sides of North Pacific Ocean may be not a coincidence,and a comparative study was made in this paper. The results show that the two seaways inundated basins share several similarities particularly in basin origin,filling processes and reservoir facies. It is suggested that reservoir facies of estuarine sandstone and shelf bar sandstone related to sea level fluctuation,which are well developed in the Cretaceous seaway covered basins in North America might have been also developed here in Palaeogene seaway inundated basins in East China. Therefore it is worth paying more attention to finding these new reservoir facies on this side of the Pacific ocean. Evidences of sedimentology and ichnology indicate that good prospects are likely.

  14. Pan-Continental Droughts in North America over the Last Millennium

    Science.gov (United States)

    Cook, Benjamin I.; Smerdon, Jason E.; Seager, Richard; Cook, Edward R.

    2014-01-01

    Regional droughts are common in North America, but pan-continental droughts extending across multiple regions, including the 2012 event, are rare relative to single-region events. Here, the tree-ring-derived North American Drought Atlas is used to investigate drought variability in four regions over the last millennium, focusing on pan-continental droughts. During the Medieval Climate Anomaly (MCA), the central plains (CP), Southwest (SW), and Southeast (SE) regions experienced drier conditions and increased occurrence of droughts and the Northwest (NW) experienced several extended pluvials. Enhanced MCA aridity in the SW and CP manifested as multidecadal megadroughts. Notably, megadroughts in these regions differed in their timing and persistence, suggesting that they represent regional events influenced by local dynamics rather than a unified, continental-scale phenomena. There is no trend in pan-continental drought occurrence, defined as synchronous droughts in three or more regions. SW, CP, and SE (SW+CP+SE) droughts are the most common, occurring in 12 percent of all years and peaking in prevalence during the twelfth and thirteenth centuries; patterns involving three other regions occur in about 8 percent of years. Positive values of the Southern Oscillation index (La Nina conditions) are linked to SW, CP, and SE (SW+CP+SE) droughts and SW, CP, and NW (SW+CP+NW) droughts, whereas CP, NW, and SE (CP+NW+SE) droughts are associated with positive values of the Pacific decadal oscillation and Atlantic multidecadal oscillation. While relatively rare, pan-continental droughts are present in the paleo record and are linked to defined modes of climate variability, implying the potential for seasonal predictability. Assuming stable drought teleconnections, these events will remain an important feature of future North American hydroclimate, possibly increasing in their severity in step with other expected hydroclimate responses to increased greenhouse gas forcing.

  15. Interpreting the variability of CO2 columns over North America using a chemistry transport model: application to SCIAMACHY data

    Directory of Open Access Journals (Sweden)

    P. S. Monks

    2008-04-01

    Full Text Available We use the GEOS-Chem chemistry transport model to interpret variability of CO2 columns and associated column-averaged volume mixing ratios (CVMRs observed by the SCIAMACHY satellite instrument during the 2003 North American growing season, accounting for the instrument averaging kernel. Model and observed columns, largely determined by surface topography, averaged on a 2°×2.5° grid, are in excellent agreement (model bias=3%, r>0.9, as expected. Model and observed CVMRs, determined by scaling column CO2 by surface pressure data, are on average within 3% but are only weakly correlated, reflecting a large positive model bias (10–15 ppmv at 50–70° N during midsummer at the peak of biospheric uptake. GEOS-Chem generally reproduces the magnitude and seasonal cycle of observed CO2 surface VMRs across North America. During midsummer we find that model CVMRs and surface VMRs converge, reflecting the instrument vertical sensitivity and the strong influence of the land biosphere on lower tropospheric CO2 columns. We use model tagged tracers to show that local fluxes largely determine CVMR variability over North America, with the largest individual CVMR contributions (1.1% from the land biosphere. Fuel sources are relatively constant while biomass burning make a significant contribution only during midsummer. We also show that non-local sources contribute significantly to total CVMRs over North America, with the boreal Asian land biosphere contributing close to 1% in midsummer at high latitudes. We used the monthly-mean Jacobian matrix for North America to illustrate that: 1 North American CVMRs represent a superposition of many weak flux signatures, but differences in flux distributions should permit independent flux estimation; and 2 the atmospheric e-folding lifetimes for many of these flux signatures are 3–4 months, beyond which time they are too well-mixed to interpret.

  16. Correlation of the Late Pleistocene Usselo Horizon (Europe) and the Clovis Layer (North America)

    Science.gov (United States)

    Kloosterman, J. B.

    2007-05-01

    In 1940, a dark charcoal-rich layer, 10 to 15cm thick, was found within the Late Pleistocene Coversands of the Netherlands, and named the Usselo Layer (de Laag van Usselo) by its discoverer, archaeologist CCJW Hijszeler (1902-1982). Usselo is a village near Enschedé, a few kilometres from the Dutch-German border. Research started after the war, and publications, both scientific and popular, came forth in the 1950s. By pollen content, the layer was dated to the Alleröd, the last interstadial of the Würm (Wisconsin) glaciation; radiocarbon dating indicated (pre-AMS) dates of about 11,200 14C BP. Identification of the layer at other localities was visual, and it was found in Belgium, France, Germany, Poland, and Belarus; it was also found in the UK and in Denmark, in which countries, however, no correlation was made with the other occurrences. Hijszeler had found the layer all over the Netherlands and abroad from Ostende to Hamburg, and he hypothesized the cause as a general wildfire provoked by the eruption of an Eiffel volcano. The European geologists and archaeologists, however, did not adopt his views and interpreted the layer as a paleosol, vitiating the chronology by representing the layer as the result of a long development, instead of as an eolian sediment laid down perhaps in a day or even less that provides us with a sharp marker horizon. The prehistoric Clovis culture of North America was found in the 1930s and dated to the Twocreekan, the last interstadial of the Wisconsin glaciation. The Clovis layer was especially investigated by archaeologist C.Vance Haynes Jr. Visually, the layer is easily identifiable with the Usselo Horizon of Europe. Its stratigraphic position is coincident with the end of the Clovis culture and with the disappearance of the Pleistocene megafauna. In Europe, there is a clear correlation with the sudden demise of the Magdalenian culture, best known for the Franco-Cantabrian cave paintings, and with megafaunal extinctions such as

  17. GIS Representation of Coal-Bearing Areas in North, Central, and South America

    Science.gov (United States)

    Tewalt, Susan J.; Kinney, Scott A.; Merrill, Matthew D.

    2008-01-01

    Worldwide coal consumption and international coal trade are projected to increase in the next several decades (Energy Information Administration, 2007). A search of existing literature indicates that in the Western Hemisphere, coal resources are known to occur in about 30 countries. The need exists to be able to depict these areas in a digital format for use in Geographic Information System (GIS) applications at small scales (large areas) and in visual presentations. Existing surficial geology GIS layers of the appropriate geologic age have been used as an approximation to depict the extent of coal-bearing areas in North, Central, and South America, as well as Greenland (fig. 1). Global surficial geology GIS data were created by the U.S. Geological Survey (USGS) for use in world petroleum assessments (Hearn and others, 2003). These USGS publications served as the major sources for the selection and creation of polygons to represent coal-bearing areas. Additional publications and maps by various countries and agencies were also used as sources of coal locations. GIS geologic polygons were truncated where literature or hardcopy maps did not indicate the presence of coal. The depicted areas are not adequate for use in coal resource calculations, as they were not adjusted for geologic structure and do not include coal at depth. Additionally, some coal areas in Central America could not be represented by the mapped surficial geology and are shown only as points based on descriptions or depictions from scientific publications or available maps. The provided GIS files are intended to serve as a backdrop for display of coal information. Three attributes of the coal that are represented by the polygons or points include geologic age (or range of ages), published rank (or range of ranks), and information source (published sources for age, rank, or physical location, or GIS geology base).

  18. Role of convection in redistributing formaldehyde to the upper troposphere over North America and the North Atlantic during the summer 2004 INTEX campaign

    OpenAIRE

    Fried, Alan; Olson, Jennifer R; Walega, James G.; Crawford, Jim H; Chen, Gao; Weibring, Petter; Richter, Dirk; Roller, Chad; Tittel, Frank; Porter, Michael; Fuelberg, Henry; Halland, Jeremy; Bertram, Timothy H; Cohen, Ronald C.; Pickering, Kenneth

    2008-01-01

    Measurements of formaldehyde (CH2O) from a tunable diode laser absorption spectrometer (TDLAS) were acquired onboard the NASA DC-8 aircraft during the summer 2004 INTEX-NA campaign to test our understanding of convection and CH2O production mechanisms in the upper troposphere (UT, 6–12 km) over continental North America and the North Atlantic Ocean. The present study utilizes these TDLAS measurements and results from a box model to (1) establish sets of conditions by which to distinguish “bac...

  19. Biography of a technology: North America's power grid through the twentieth century

    Science.gov (United States)

    Cohn, Julie A.

    conservation. While this project explores the history of how and why North America has a huge interconnected power system, it also offers insights into the challenges the grid poses for our energy future.

  20. Projected changes to rain-on-snow events over North America

    Science.gov (United States)

    Jeong, Dae Il; Sushama, Laxmi

    2016-04-01

    Rain-on-snow (ROS) events have significant impacts on cold region ecosystems and water-related natural hazards, and therefore it is very important to assess how this hydro-meteorological phenomenon will evolve in a changing climate. This study evaluates the changes in ROS characteristics (i.e., frequency, amounts, and runoff) for the future 2041-2070 period with respect to the current 1976-2005 period over North America using six simulations, based on two Canadian RCMs, driven by two driving GCMs for RCP4.5 and 8.5 emission pathways. Projected changes to extreme runoff caused by the changes of the ROS characteristics are also evaluated. All simulations suggest general increases in ROS days in late autumn, winter, and early spring periods for most Canadian regions and northwestern USA for the future period, due to an increase in rain days in a warmer climate. Increases in the future ROS amounts are projected mainly due to an increase in ROS days, although increases in precipitation intensity also contributes to the future increases. Future ROS runoff is expected to increase more than future ROS amounts during snowmelt months as ROS events usually enhance runoff, given the land state and asociated reduced soil infiltration rate and also due to the faster snowmelt rate occuring during these events. The simulations also show that ROS events usually lead to extreme runoff over most of Canada and north-western and -central USA in the January-May snowmelt months for the current period and these show no significant changes in the future climate. However, the future ROS to total runoff ratio will significantly decrease for western and eastern Canada as well as north-western USA for these months, due to an overall increase of the fraction of direct snowmelt and rainfall generated runoff in a warmer climate. These results indicate the difficulties of flood risk and water resource managements in the future, particularly in Canada and north-western and -central USA, requiring

  1. Fat dynamics of arctic-nesting sandpipers during spring in mid-continental North America

    Science.gov (United States)

    Krapu, G.L.; Eldridge, J.L.; Gratto-Trevor, C. L.; Buhl, D.A.

    2006-01-01

    departure from temperate mid-continental North America to meet their energy requirements for migration and part of their nutrient needs for reproduction. ?? The American Ornithologists' Union, 2006.

  2. Handymen, Hippies and Healing: Social Transformation through the DIY Movement (1940s to 1970s in North America

    Directory of Open Access Journals (Sweden)

    Cathy D Smith

    2014-03-01

    Full Text Available This paper explores the relation between the ‘DIY’ (‘do-it-yourself’ movement and ‘DIY architecture’, and the notion of social transformation, in examples of DIY manuals and discourse of North America drawn from the 1940s to the 1970s. The DIY movement emerged as a significant phenomenon in North America of the 1950s, where it was associated with a mainstream audience and a residential market. By the 1960s, the DIY approach was embraced by the North American counterculture as a self-sustaining sensibility that could overcome a reliance on the mainstream, consumerist society that spurned it. On the surface, the association of DIY with the counterculture and countercultural architects appears to denote a significant ideological shift from its original association with the beliefs and culture of mainstream North America and the nuclear family. However, one of the key characterisations of the DIY movement identified in the present paper is the way it is bound to the notion of social identity and transformation, regardless of ideology. Particular attention is paid to DIY manuals and discourse of the 1950s.

  3. The potential distribution of invading Helicoverpa armigera in North America: is it just a matter of time?

    Directory of Open Access Journals (Sweden)

    Darren J Kriticos

    Full Text Available Helicoverpa armigera has recently invaded South and Central America, and appears to be spreading rapidly. We update a previously developed potential distribution model to highlight the global invasion threat, with emphasis on the risks to the United States. The continued range expansion of H. armigera in Central America is likely to change the invasion threat it poses to North America qualitatively, making natural dispersal from either the Caribbean islands or Mexico feasible. To characterise the threat posed by H. armigera, we collated the value of the major host crops in the United States growing within its modelled potential range, including that area where it could expand its range during favourable seasons. We found that the annual value of crops that would be exposed to H. armigera totalled approximately US$78 billion p.a., with US$843 million p.a. worth growing in climates that are optimal for the pest. Elsewhere, H. armigera has developed broad-spectrum pesticide resistance; meaning that if it invades the United States, protecting these crops from significant production impacts could be challenging. It may be cost-effective to undertake pre-emptive biosecurity activities such as slowing the spread of H. armigera throughout the Americas, improving the system for detecting H. armigera, and methods for rapid identification, especially distinguishing between H. armigera, H. zea and potential H. armigera x H. zea hybrids. Developing biological control programs, especially using inundative techniques with entomopathogens and parasitoids could slow the spread of H. armigera, and reduce selective pressure for pesticide resistance. The rapid spread of H. armigera through South America into Central America suggests that its spread into North America is a matter of time. The likely natural dispersal routes preclude aggressive incursion responses, emphasizing the value of preparatory communication with agricultural producers in areas suitable for

  4. Forest cover of North America in the 1970s mapped using Landsat MSS data

    Science.gov (United States)

    Feng, M.; Sexton, J. O.; Channan, S.; Townshend, J. R.

    2015-12-01

    machines. As the first result of our global mapping effort, we present the forest cover for North America. More than 25,000 Landsat MSS scenes were processed to provide a 120-meter resolution forest cover for North America, which will be made publicly available on the GLCF website (http://www.landcover.org).

  5. NAOMI: The trials and tribulations of implementing a heroin assisted treatment study in North America

    Directory of Open Access Journals (Sweden)

    Laliberté Nancy

    2009-01-01

    Full Text Available Abstract Background Opioid addiction is a chronic, relapsing disease and remains a major public health challenge. Despite important expansions of access to conventional treatments, there are still significant proportions of affected individuals who remain outside the reach of the current treatment system and who contribute disproportionately to health care and criminal justice costs as well as to public disorder associated with drug addiction. The NAOMI study is a Phase III randomized clinical trial comparing injectable heroin maintenance to oral methadone. The study has ethics board approval at its Montréal and Vancouver sites, as well as from the University of Toronto, the New York Academy of Medicine and Johns Hopkins University. The main objective of the NAOMI Study is to determine whether the closely supervised provision of injectable, pharmaceutical-grade opioid agonist is more effective than methadone alone in recruiting, retaining, and benefiting chronic, opioid-dependent, injection drug users who are resistant to current standard treatment options. Methods The case study submitted chronicles the challenges of getting a heroin assisted treatment trial up and running in North America. It describes: a brief background on opioid addiction; current standard therapies for opioid addiction; why there is/was a need for a heroin assisted treatment trial; a description of heroin assisted treatment; the beginnings of creating the NAOMI study in North America; what is the NAOMI study; the science and politics of the NAOMI study; getting NAOMI started in Canada; various requirements and restrictions in getting the study up and running; recruitment into the study; working with the media; a status report on the study; and a brief conclusion from the authors' perspectives. Results and conclusion As this is a case study, there are no specific results or main findings listed. The case study focuses on: the background of the study; what it took to get

  6. A model-data intercomparison of CO2 exchange across North America: Results from the North American Carbon Program Site Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Schwalm, C.R.; Williams, C.A.; Schaefer, K.; Anderson, R.; Arain, M.A.; Baker, I.; Black, T.A.; Chen, G.; Ciais, P.; Davis, K. J.; Desai, A. R.; Dietze, M.; Dragoni, D.; Fischer, M.L.; Flanagan, L.B.; Grant, R.F.; Gu, L.; Hollinger, D.; Izaurralde, R.C.; Kucharik, C.; Lafleur, P.M.; Law, B.E.; Li, L.; Li, Z.; Liu, S.; Lokupitiya, E.; Luo, Y.; Ma, S.; Margolis, H.; Matamala, R.; McCaughey, H.; Monson, R. K.; Oechel, W. C.; Peng, C.; Poulter, B.; Price, D.T.; Riciutto, D.M.; Riley, W.J.; Sahoo, A.K.; Sprintsin, M.; Sun, J.; Tian, H.; Tonitto, C.; Verbeeck, H.; Verma, S.B.

    2011-06-01

    Our current understanding of terrestrial carbon processes is represented in various models used to integrate and scale measurements of CO{sub 2} exchange from remote sensing and other spatiotemporal data. Yet assessments are rarely conducted to determine how well models simulate carbon processes across vegetation types and environmental conditions. Using standardized data from the North American Carbon Program we compare observed and simulated monthly CO{sub 2} exchange from 44 eddy covariance flux towers in North America and 22 terrestrial biosphere models. The analysis period spans {approx}220 site-years, 10 biomes, and includes two large-scale drought events, providing a natural experiment to evaluate model skill as a function of drought and seasonality. We evaluate models' ability to simulate the seasonal cycle of CO{sub 2} exchange using multiple model skill metrics and analyze links between model characteristics, site history, and model skill. Overall model performance was poor; the difference between observations and simulations was {approx}10 times observational uncertainty, with forested ecosystems better predicted than nonforested. Model-data agreement was highest in summer and in temperate evergreen forests. In contrast, model performance declined in spring and fall, especially in ecosystems with large deciduous components, and in dry periods during the growing season. Models used across multiple biomes and sites, the mean model ensemble, and a model using assimilated parameter values showed high consistency with observations. Models with the highest skill across all biomes all used prescribed canopy phenology, calculated NEE as the difference between GPP and ecosystem respiration, and did not use a daily time step.

  7. Mergers in the power supply sector. Empirical analysis of mergers in the nineties in North America and Europe; Unternehmenszusammenschluesse in der Energieversorgung. Empirische Analyse der Uebernahmewelle der 1990er Jahre in Nordamerika und Europa

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, T.W.

    2006-07-01

    The author investigates the effects of 529 mergers in the European and North American power industries between 1990 and 2002. The focus is on the effects on the capital market and the changes in the utilities' performance in successive years. It is assumed that as a rule mergers resulted in a lower value of the companies concerned. On the other hand, the target businesses appear to have obtained added value in the same period. Apart from the fight for market power, the author identifies especially financial synergies as an important motive. (orig.)

  8. Surface-air mercury fluxes across Western North America: A synthesis of spatial trends and controlling variables

    Science.gov (United States)

    Eckley, Chris S.; Tate, Michael T.; Lin, Che-Jen; Gustin, Mae S.; Dent, Stephen; Eagles-Smith, Collin A.; Lutz, Michelle A; Wickland, Kimberly; Wang, Bronwen; Gray, John E.; Edwards, Grant; Krabbenhoft, David P.; Smith, David

    2016-01-01

    Mercury (Hg) emission and deposition can occur to and from soils, and are an important component of the global atmospheric Hg budget. This paper focuses on synthesizing existing surface-air Hg flux data collected throughout the Western North American region and is part of a series of geographically focused Hg synthesis projects. A database of existing Hg flux data collected using the dynamic flux chamber (DFC) approach from almost a thousand locations was created for the Western North America region. Statistical analysis was performed on the data to identify the important variables controlling Hg fluxes and to allow spatiotemporal scaling. The results indicated that most of the variability in soil-air Hg fluxes could be explained by variations in soil-Hg concentrations, solar radiation, and soil moisture. This analysis also identified that variations in DFC methodological approaches were detectable among the field studies, with the chamber material and sampling flushing flow rate influencing the magnitude of calculated emissions. The spatiotemporal scaling of soil-air Hg fluxes identified that the largest emissions occurred from irrigated agricultural landscapes in California. Vegetation was shown to have a large impact on surface-air Hg fluxes due to both a reduction in solar radiation reaching the soil as well as from direct uptake of Hg in foliage. Despite high soil Hg emissions from some forested and other heavily vegetated regions, the net ecosystem flux (soil flux + vegetation uptake) was low. Conversely, sparsely vegetated regions showed larger net ecosystem emissions, which were similar in magnitude to atmospheric Hg deposition (except for the Mediterranean California region where soil emissions were higher). The net ecosystem flux results highlight the important role of landscape characteristics in effecting the balance between Hg sequestration and (re-)emission to the atmosphere.

  9. Interannual Variation in Baseline Ozone on the Western Coast of North America and Its Influence on Urban Air Quality

    Science.gov (United States)

    Wigder, N. L.; Jaffe, D. A.; Lin, M.; Fiore, A. M.; Macdonald, A.; Gong, S.

    2011-12-01

    Baseline ozone (O3) has been defined as the distribution of mixing ratios from a site when it is not influenced by locally emitted pollution (McDonald-Buller et al., 2011; NRC, 2009; TF HTAP, 2007). In this study, we set out to understand the interannual variation (IAV) in baseline O3 along the western coast of North America and its influence on surface air quality in urban environments. Baseline data for this study comes from Trinidad Head, CA, Mount Bachelor, OR, Cheeka Peak, WA, Jackson Visitor Center, WA and Whistler Mountain, BC. We address four key questions: Do baseline observations on the western coast of North America exhibit similar IAV? How well can satellites identify IAV in baseline O3 along the western coast of North America? How does the baseline IAV influence urban air quality and O3 regulatory exceedance days? How well can global chemical transport models capture the IAV in baseline O3? We examine the deseasonalized baseline data to identify IAV in boundary layer air and free tropospheric air separately, as well as the combination of these datasets. Preliminary results show that the IAV (one sigma) in monthly mean O3 at the baseline sites ranges from 2.3-4.0 ppbv, based on data available from 2002-2010. All sites show some degree of correlation in IAV, with Pearson's correlation values of r=0.3-0.6 (p≤0.05). Using level 3 monthly averaged Tropospheric Emission Spectrometer (TES) data, we find correlations in O3 IAV with the baseline sites (r=0.4, p≤0.01). This analysis is being repeated with level 2 TES data. An analysis of the O3 IAV in urban/suburban areas near the baseline sites shows a relationship between the IAV present in the baseline sites and the IAV of these urban/suburban regions (r=0.3-0.6, p≤0.05), which can contribute to air quality regulation exceedances. We will also examine the baseline IAV with two global chemical transport models, the Canadian GEM-MACH model and the GFDL AM3 model, which will provide information on the

  10. Recent changes in the frequency of freezing precipitation in North America and Northern Eurasia

    Science.gov (United States)

    Groisman, Pavel Ya; Bulygina, Olga N.; Yin, Xungang; Vose, Russell S.; Gulev, Sergey K.; Hanssen-Bauer, Inger; Førland, Eirik

    2016-04-01

    Freezing rain and freezing drizzle events represent a critical feature of many regions of the world. Even at low intensities, these events often result in natural hazards that cause damage to housing, communication lines, and other man-made infrastructure. These events usually occur near the 0 °C isotherm. In a changing climate, this isotherm will not disappear, but its position in space and time will likely change as will the geography of freezing precipitation. A larger influx of water vapor into the continents from the oceans may also increase the amount and frequency of freezing precipitation events. This paper assesses our current understanding of recent changes in freezing precipitation for the United States, Canada, Norway, and Russia. The research is part of a larger GEWEX Cross-Cut Project addressing ‘cold/shoulder season precipitation near 0 °C’. Using an archive of 874 long-term time series (40 years of data) of synoptic observations for these four countries, we document the climatology of daily freezing rain and freezing drizzle occurrences as well as trends therein. The regions with the highest frequency of freezing rains (from 3 to 8 days per year) reside in the northeastern quadrant of the conterminous United States and adjacent areas of southeastern Canada south of 50 °N and over the south and southwest parts of the Great East European Plain. The frequency of freezing drizzle exceeds the frequency of freezing rain occurrence in all areas. During the past decade, the frequency of freezing rain events somewhat decreased over the southeastern US. In North America north of the Arctic Circle, it increased by about 1 day yr-1. Over Norway, freezing rain occurrences increased substantially, especially in the Norwegian Arctic. In European Russia and western Siberia, the frequency of freezing rain somewhat increased (except the southernmost steppe regions and the Arctic regions) while freezing drizzle frequency decreased over entire Russia.

  11. An overview of observations and assessment of forest carbon dynamics following disturbance in North America

    Science.gov (United States)

    Goetz, S. J.; Bond-Lamberty, B. P.

    2012-12-01

    Disturbance processes of various types substantially modify ecosystem carbon dynamics both temporally and spatially, and constitute a fundamental part of larger landscape-level dynamics. Forests typically lose carbon for several years to several decades following severe disturbance, but our understanding of the duration and dynamics of post-disturbance forest carbon fluxes remains limited. We capitalize on a recent North American Carbon Program disturbance synthesis to discuss techniques and future work needed to better understand carbon dynamics after forest disturbance. Specifically, we address three topics: (1) the history, spatial distribution, and characteristics of different types of disturbance (in particular fire, insects, and harvest) in North America; (2) the integrated measurements and experimental designs required to quantify forest carbon dynamics in the years and decades after disturbance, as presented in a series of case studies; and (3) a synthesis of the greatest uncertainties spanning these studies, as well as the utility of multiple types of observations in understanding their dynamics. The case studies - in the southeast U.S., central boreal Canada, U.S. Rocky Mountains, and Pacific Northwest - explore how different measurements can be used to constrain and understand carbon dynamics in regrowing forests, with the most important measurements summarized for each disturbance type. We identify disturbance severity and history as key but highly uncertain factors driving post-disturbance carbon source-sink dynamics across all disturbance types. We suggest integrative analyses using multiple lines of evidence, increased measurement capabilities, shared models and online data sets, and innovative numerical algorithms hold promise for improved understanding and prediction of carbon dynamics in disturbance-prone forests.

  12. Revisiting the evidence of increasing springtime ozone mixing ratios in the free troposphere over western North America

    Science.gov (United States)

    Lin, Meiyun; Horowitz, Larry W.; Cooper, Owen R.; Tarasick, David; Conley, Stephen; Iraci, Laura T.; Johnson, Bryan; Leblanc, Thierry; Petropavlovskikh, Irina; Yates, Emma L.

    2015-10-01

    We present a 20 year time series of in situ free tropospheric ozone observations above western North America during springtime and interpret results using hindcast simulations (1980-2014) conducted with the Geophysical Fluid Dynamics Laboratory global chemistry-climate model (GFDL AM3). Revisiting the analysis of Cooper et al., we show that sampling biases can substantially influence calculated trends. AM3 cosampled in space and time with observations reproduces the observed ozone trend (0.65 ± 0.32 ppbv yr-1) over 1995-2008 (in simulations either with or without time-varying emissions), whereas AM3 "true median" with continuous temporal and spatial sampling indicates an insignificant trend (0.25 ± 0.32 ppbv yr-1). Extending this analysis to 1995-2014, we find a weaker ozone trend of 0.31 ± 0.21 ppbv yr-1 from observations and 0.36 ± 0.18 ppbv yr-1 from AM3 "true median." Rising Asian emissions and global methane contribute to this increase. While interannual variability complicates the attribution of ozone trends, multidecadal hindcasts can aid in the estimation of robust confidence limits for trends based on sparse observational records.

  13. Fine-scale geographical origin of an insect pest invading North America.

    Science.gov (United States)

    Hosokawa, Takahiro; Nikoh, Naruo; Fukatsu, Takema

    2014-01-01

    Invasive species may rapidly spread throughout new areas once introduced, which may potentially lead to serious damage to local fauna and flora. Information on geographical origins, introduction routes, and biology in native regions of such invasive species is of critical importance in identifying means of transport, preventing reintroduction, and establishing control/eradication methods. The plataspid stinkbug Megacopta cribraria, known as kudzu bug, recently invaded North America and now has become not only an agricultural pest of soybean but also a nuisance pest. Here we investigate the geographical origin of the invasive M. cribraria populations. Phylogeographical analyses based on 8.7 kb mitochondrial DNA sequences of the introduced and East Asian native Megacopta populations identified a well-supported clade consisting of the introduced populations and M. punctatissima populations in the Kyushu region of Japan, which strongly suggests that the invading M. cribraria populations are derived from a M. punctatissima population in the Kyushu region. Therefore, the region is proposed as a promising source of natural enemies for biological control of the invasive pest. Based on the phylogenetic information, relationship and treatment of the two Megacopta species are discussed. PMID:24551228

  14. Multiscale perspectives of fire, climate and humans in western North America and the Jemez Mountains, USA.

    Science.gov (United States)

    Swetnam, Thomas W; Farella, Joshua; Roos, Christopher I; Liebmann, Matthew J; Falk, Donald A; Allen, Craig D

    2016-06-01

    Interannual climate variations have been important drivers of wildfire occurrence in ponderosa pine forests across western North America for at least 400 years, but at finer scales of mountain ranges and landscapes human land uses sometimes over-rode climate influences. We reconstruct and analyse effects of high human population densities in forests of the Jemez Mountains, New Mexico from ca 1300 CE to Present. Prior to the 1680 Pueblo Revolt, human land uses reduced the occurrence of widespread fires while simultaneously adding more ignitions resulting in many small-extent fires. During the 18th and 19th centuries, wet/dry oscillations and their effects on fuels dynamics controlled widespread fire occurrence. In the late 19th century, intensive livestock grazing disrupted fuels continuity and fire spread and then active fire suppression maintained the absence of widespread surface fires during most of the 20th century. The abundance and continuity of fuels is the most important controlling variable in fire regimes of these semi-arid forests. Reduction of widespread fires owing to reduction of fuel continuity emerges as a hallmark of extensive human impacts on past forests and fire regimes.This article is part of the themed issue 'The interaction of fire and mankind'. PMID:27216525

  15. Camper learning and friendship at pediatric oncology camps in North America.

    Science.gov (United States)

    Martiniuk, Alexandra L C; Amylon, Michael D; Briery, Brandon G; Shea-Perry, Marci; Kelsey, Kathleen P; Lam, Gary W; Körver, Sarah

    2014-01-01

    Children with cancer and their families often attend specialized camps (therapeutic recreation) through their cancer treatment journey, yet little is known about the effects of these camps. A qualitative cohort study was used to assess learning and friendship development by campers attending one of four pediatric oncology summer camps during 2010 in North America. Standardized perceived change questionnaires developed by the American Camp Association were administered following camp attendance. Five-hundred and eighteen campers were enrolled: 120 (age 6-9 years) and 398 (age 10 and older). The largest positive response from the younger campers was observed for the question, "At camp did you learn to look forward to trying new activities?" For the older campers' survey, the items "Becoming better at enjoying being with my friends," "Becoming better at helping my friends have a good time when they are with me," and "Becoming better at getting to know more things about my friends" were perceived to increase the most for the majority of campers compared to other questions. Items for which older campers most often perceived little change were "Becoming better at choosing people who would be good friends to be with" and "Becoming better at understanding friends' emotions." Camp helps children learn new activities as well as enjoy good times with friends. Dealing with one's own mistakes and understanding others' emotions are areas for improvement. Ultimately it is hoped that these skills gained at camp will help build coping and resiliency for children/siblings affected by pediatric cancers. PMID:24364990

  16. Temporal and spatial aspects of peatland initiation following deglaciation in North America

    Science.gov (United States)

    Gorham, E.; Lehman, C.; Dyke, A.; Janssens, J.; Dyke, L.

    2007-01-01

    A set of simple ecological models accounts well for the cumulative initiation of peatlands throughout North America in relation to glacial retreat. The most parsimonious form incorporates, first, a delay term to account for the lag during which newly deglaciated land became suitable for peatland initiation and, second, an intrinsic rate of initiation related to the probability of migration and establishment of plant propagules from elsewhere. The goodness of fit of the models, based on 1680 basal-peat dates throughout the continent, allows projection of past trends into the future. Factors contributing to the lag of about 4000 years between deglaciation and peatland initiation are suggested and data on colonization of deglaciated land by beavers (known to initiate peatlands) are presented. The rate of peatland initiation peaked between 7000 and 8000 years ago, but remains appreciable today. A marked depression of peatland initiation (8360-8040 BP) interrupted the peak rate. The time of the interruption matches the 8200 BP cold-dry event recorded in Greenland ice cores, and suggests that this event caused a substantial, continent-wide depression of an important ecosystem function, i.e., carbon sequestration from the atmosphere by peat deposition. Spontaneous initiation of new peatlands is projected to continue for millennia to come. ?? 2006 Elsevier Ltd. All rights reserved.

  17. The Effects of North America Free Trade Agreement on Mexican Environmental Policy (1994-2004

    Directory of Open Access Journals (Sweden)

    Ningu J.   Kenneth

    2006-01-01

    Full Text Available The scope of this study was to analyze the implementation of the environmental policy and the way Mexico has integrated the environmental aspects into a North America Free Trade Agreement (NAFTA. We are aware of the fact that many environmental costs do not necessarily reflect the environmental damage. Environmental costs are often defined by determining either the willingness of the users to pay for the damages or for admittance of claims for damage. Since everyone has the right to a clean and thriving natural environment it is the policy maker who determines the basis of admittance of the most correct means to determine environmental costs in order to reduce the damages. Methodologically, we analyzed the existence and implementation of environmental policy. Instead of looking at the tradeoff between trade related incentives and environmental considerations, we analyzed how trade-offs changes under free trade effects the policy issues. When compared the countries environmental policy and the NAFTA stipulations we found that Mexico has a well-defined environmental policy but less integrated in the free trade agreement. The decision makers have increased the concessions of consumption of fixed capital as a means to increase gains from trade. This has lead to increased environmental damage, natural resource depletion and environmental costs.

  18. Evolution of puma lentivirus in bobcats (Lynx rufus) and mountain lions (Puma concolor) in North America

    Science.gov (United States)

    Lee, Justin S.; Bevins, Sarah N.; Serieys, Laurel E.K.; Vickers, Winston; Logan, Ken A.; Aldredge, Mat; Boydston, Erin E.; Lyren, Lisa M.; McBride, Roy; Roelke-Parker, Melody; Pecon-Slattery, Jill; Troyer, Jennifer L.; Riley, Seth P.; Boyce, Walter M.; Crooks, Kevin R.; VandeWoude, Sue

    2014-01-01

    Mountain lions (Puma concolor) throughout North and South America are infected with puma lentivirus clade B (PLVB). A second, highly divergent lentiviral clade, PLVA, infects mountain lions in southern California and Florida. Bobcats (Lynx rufus) in these two geographic regions are also infected with PLVA, and to date, this is the only strain of lentivirus identified in bobcats. We sequenced full-length PLV genomes in order to characterize the molecular evolution of PLV in bobcats and mountain lions. Low sequence homology (88% average pairwise identity) and frequent recombination (1 recombination breakpoint per 3 isolates analyzed) were observed in both clades. Viral proteins have markedly different patterns of evolution; sequence homology and negative selection were highest in Gag and Pol and lowest in Vif and Env. A total of 1.7% of sites across the PLV genome evolve under positive selection, indicating that host-imposed selection pressure is an important force shaping PLV evolution. PLVA strains are highly spatially structured, reflecting the population dynamics of their primary host, the bobcat. In contrast, the phylogeography of PLVB reflects the highly mobile mountain lion, with diverse PLVB isolates cocirculating in some areas and genetically related viruses being present in populations separated by thousands of kilometers. We conclude that PLVA and PLVB are two different viral species with distinct feline hosts and evolutionary histories.

  19. Songbirds as sentinels of mercury in terrestrial habitats of eastern North America.

    Science.gov (United States)

    Jackson, Allyson K; Evers, David C; Adams, Evan M; Cristol, Daniel A; Eagles-Smith, Collin; Edmonds, Samuel T; Gray, Carrie E; Hoskins, Bart; Lane, Oksana P; Sauer, Amy; Tear, Timothy

    2015-03-01

    Mercury (Hg) is a globally distributed environmental contaminant with a variety of deleterious effects in fish, wildlife, and humans. Breeding songbirds may be useful sentinels for Hg across diverse habitats because they can be effectively sampled, have well-defined and small territories, and can integrate pollutant exposure over time and space. We analyzed blood total Hg concentrations from 8,446 individuals of 102 species of songbirds, sampled on their breeding territories across 161 sites in eastern North America [geometric mean Hg concentration = 0.25 μg/g wet weight (ww), range species and sites. Blood Hg concentrations in adult invertebrate-eating songbirds were consistently higher in wetland habitats (freshwater or estuarine) than upland forests. Generally, adults exhibited higher blood Hg concentrations than juveniles within each habitat type. We used model results to examine species-specific differences in blood Hg concentrations during this time period, identifying potential Hg sentinels in each region and habitat type. Our results present the most comprehensive assessment of blood Hg concentrations in eastern songbirds to date, and thereby provide a valuable framework for designing and evaluating risk assessment schemes using sentinel songbird species in the time after implementation of the new atmospheric Hg standards. PMID:25492585

  20. Songbirds as sentinels of mercury in terrestrial habitats of eastern North America

    Science.gov (United States)

    Jackson, Allyson K.; Evers, David C.; Adams, Evan M.; Cristol, Daniel A.; Eagles-Smith, Collin A.; Edmonds, Samuel T.; Gray, Carrie E.; Hoskins, Bart; Lane, Oksana P.; Sauer, Amy; Tear, Timothy

    2015-01-01

    Mercury (Hg) is a globally distributed environmental contaminant with a variety of deleterious effects in fish, wildlife, and humans. Breeding songbirds may be useful sentinels for Hg across diverse habitats because they can be effectively sampled, have well-defined and small territories, and can integrate pollutant exposure over time and space. We analyzed blood total Hg concentrations from 8,446 individuals of 102 species of songbirds, sampled on their breeding territories across 161 sites in eastern North America [geometric mean Hg concentration = 0.25 μg/g wet weight (ww), range species and sites. Blood Hg concentrations in adult invertebrate-eating songbirds were consistently higher in wetland habitats (freshwater or estuarine) than upland forests. Generally, adults exhibited higher blood Hg concentrations than juveniles within each habitat type. We used model results to examine species-specific differences in blood Hg concentrations during this time period, identifying potential Hg sentinels in each region and habitat type. Our results present the most comprehensive assessment of blood Hg concentrations in eastern songbirds to date, and thereby provide a valuable framework for designing and evaluating risk assessment schemes using sentinel songbird species in the time after implementation of the new atmospheric Hg standards.

  1. Comparison of earthquake source spectra and attenuation in eastern North America and southeastern Australia

    Science.gov (United States)

    Allen, T.I.; Atkinson, G.M.

    2007-01-01

    The paucity of ground-motion data in stable continental regions (SCRs) remains a key limitation when developing relations that seek to predict effects of strong ground shaking from large damaging earthquakes. It is desirable to combine data from more than one SCR to increase database size, but this raises questions as to whether the source and attenuation properties of the SCRs are equivalent. We compare recently compiled spectral-amplitude databases from small to moderate events (moment magnitudes, 2.0 ??? M ??? 5.0) in both southeastern Australia and eastern North America (ENA). Both are SCRs but are widely separated, spatially and in tectonic history. We statistically compare ground motions by plotting mean and standard deviations of spectral amplitudes for data grouped in magnitude and distance bins. These comparisons show that the source and attenuation properties of the two regions are very similar, in particular, at shorter hypocentral distances R (i.e., R < 70 km). At larger distances, regional attenuation differences are observed that may be attributed to differences in crustal structure. We conclude that it is valid to combine the Australian and ENA ground-motion datasets in the development of ground-motion prediction equations, with some limitations in frequency and distance ranges. These ground-motion relations may serve as generic functions for SCRs around the world.

  2. A sharp lithosphere-asthenosphere boundary imaged beneath eastern North America.

    Science.gov (United States)

    Rychert, Catherine A; Fischer, Karen M; Rondenay, Stéphane

    2005-07-28

    Plate tectonic theory hinges on the concept of a relatively rigid lithosphere moving over a weaker asthenosphere, yet the nature of the lithosphere-asthenosphere boundary remains poorly understood. The gradient in seismic velocity that occurs at this boundary is central to constraining the physical and chemical properties that create differences in mechanical strength between the two layers. For example, if the lithosphere is simply a thermal boundary layer that is more rigid owing to colder temperatures, mantle flow models indicate that the velocity gradient at its base would occur over tens of kilometres. In contrast, if the asthenosphere is weak owing to volatile enrichment or the presence of partial melt, the lithosphere-asthenosphere boundary could occur over a much smaller depth range. Here we use converted seismic phases in eastern North America to image a very sharp seismic velocity gradient at the base of the lithosphere-a 3-11 per cent drop in shear-wave velocity over a depth range of 11 km or less at 90-110 km depth. Such a strong, sharp boundary cannot be reconciled with a purely thermal gradient, but could be explained by an asthenosphere that contains a few per cent partial melt or that is enriched in volatiles relative to the lithosphere.

  3. The Pleistocene biogeography of eastern North America: A nonmigration scenario for deciduous forest

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C. [Argonne National Lab., IL (United States). Environmental Research Div.; Iltis, H. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Botany

    1998-12-31

    The current reconstruction of the vegetation of eastern North America at the last glacial maximum postulates a very wide zone of tundra and boreal forest south of the ice. This reconstruction requires that the deciduous forest retreated far to the south. The authors believe that this reconstruction is seriously in error. Geologic evidence for glacial activity or tundra is absent from the southern Appalachians. Positive evidence for boreal forest is based on pollen identifications for Picea, Betula, and Pinus, when in reality southern members of these genera have pollen that cannot be distinguished from that of northern members. Further, pollen of typical southern species such as oaks and hickories occurs throughout profiles that past authors had labeled boreal. Pollen evidence for a far southern deciduous forest refuge is lacking. Data on endemics are particularly challenging for the scenario in which deciduous forest migrated to the south and back. The southern Appalachian region is rife with endemics that are often extreme-habitat specialists unable to migrate. The previously glaciated zone is almost completely lacking in endemics. Outlier populations, range boundaries, and absence of certain hybrids all argue against a large boreal zone. The new reconstruction postulates a cold zone no more than 75--100 miles wide south of the ice in the East.

  4. Fine-scale geographical origin of an insect pest invading North America.

    Directory of Open Access Journals (Sweden)

    Takahiro Hosokawa

    Full Text Available Invasive species may rapidly spread throughout new areas once introduced, which may potentially lead to serious damage to local fauna and flora. Information on geographical origins, introduction routes, and biology in native regions of such invasive species is of critical importance in identifying means of transport, preventing reintroduction, and establishing control/eradication methods. The plataspid stinkbug Megacopta cribraria, known as kudzu bug, recently invaded North America and now has become not only an agricultural pest of soybean but also a nuisance pest. Here we investigate the geographical origin of the invasive M. cribraria populations. Phylogeographical analyses based on 8.7 kb mitochondrial DNA sequences of the introduced and East Asian native Megacopta populations identified a well-supported clade consisting of the introduced populations and M. punctatissima populations in the Kyushu region of Japan, which strongly suggests that the invading M. cribraria populations are derived from a M. punctatissima population in the Kyushu region. Therefore, the region is proposed as a promising source of natural enemies for biological control of the invasive pest. Based on the phylogenetic information, relationship and treatment of the two Megacopta species are discussed.

  5. Monarch butterflies cross the Appalachians from the west to recolonize the east coast of North America.

    Science.gov (United States)

    Miller, Nathan G; Wassenaar, Leonard I; Hobson, Keith A; Norris, D Ryan

    2011-02-23

    Each spring, millions of monarch butterflies (Danaus plexippus) migrate from overwintering sites in Mexico to recolonize eastern North America. However, few monarchs are found along the east coast of the USA until mid-summer. Brower (Brower, L. P. 1996 J. Exp. Biol. 199, 93-103.) proposed that east coast recolonization is accomplished by individuals migrating from the west over the Appalachians, but to date no evidence exists to support this hypothesis. We used hydrogen (δD) and carbon (δ(13)C) stable isotope measurements to estimate natal origins of 90 monarchs sampled from 17 sites along the eastern United States coast. We found the majority of monarchs (88%) originated in the mid-west and Great Lakes regions, providing, to our knowledge, the first direct evidence that second generation monarchs born in June complete a (trans-) longitudinal migration across the Appalachian mountains. The remaining individuals (12%) originated from parents that migrated directly from the Gulf coast during early spring. Our results provide evidence of a west to east longitudinal migration and provide additional rationale for conserving east coast populations by identifying breeding sources. PMID:20630891

  6. Phylogeography of Camassia quamash in western North America: postglacial colonization and transport by indigenous peoples.

    Science.gov (United States)

    Tomimatsu, Hiroshi; Kephart, Susan R; Vellend, Mark

    2009-09-01

    Recent human activities have spread numerous plant species across the globe, yet it is unclear to what degree historical human activities influenced plant dispersal. In western North America, Camassia quamash was one of the most important food plants for indigenous peoples, who transported its propagules either intentionally or accidentally. We investigated how human and natural dispersal might have contributed to the current pattern of spatial genetic structure in C. quamash by performing phylogeographical surveys at two geographical scales. We sequenced two noncoding regions of chloroplast deoxyribonucleic acid (DNA) in 226 individuals from 53 populations of C. quamash as well as 126 individuals from 21 populations of the non-food plant Zigadenus venenosus. Contrary to the expectation of anthropogenic transport, C. quamash populations did not exhibit weaker genetic structure than Z. venenosus populations. We also failed to find convincing evidence for signatures of transport. Instead, our data showed strong effects of past glaciation and geographical barriers of the mountains in the Cascade Range, Olympic Peninsula and Vancouver Island. West of the Cascades, the species appears to have largely migrated northward from a southern refugium after deglaciation, whereas few populations having a highly divergent haplotype might have survived in southwestern Washington. Our data suggest that despite substantial ethnobotanical evidence for anthropogenic transport, the current pattern of genetic structure of C. quamash does not show any detectable signatures of transport by indigenous peoples and is better understood as the result of natural dispersal processes.

  7. Toward fisheries sustainability in North America: Issues, challenges, and strategies for action

    Science.gov (United States)

    MacDonald, D.D.; Knudsen, E.E.

    2004-01-01

    Many fisheries in North America are severely depleted and trending downwards. In an effort to find ways of reversing this disturbing situation, the American Fisheries Society and the Sustainable Fisheries Foundation invited leading experts in fisheries science and aquatic resource management to share their thoughts and insights in this book. These experts were asked to identify the factors that are currently impairing our ability to effectively manage fisheries resources and propose creative solutions for addressing the most challenging issues affecting fisheries sustainability. Based on the information that was provided by the experts (i.e., as presented in the earlier chapters of this book), it is apparent that a wide range of human activities are adversely affecting our shared fisheries resources and the aquatic habitats upon which they depend. The most challenging problems stem from causes that are largely beyond the scope of traditional fisheries management (e.g., human population growth, resource consumption patterns, global climate change, broad land-use patterns). It is also apparent that resolution of these challenges will require a new approach to fisheries management - one that effectively integrates economic, social, and environmental interests into a decision-making framework that supports fisheries sustainability. The key strategies for supporting such a transition toward a more holistic and comprehensive approach to managing the human activities that influence fisheries and aquatic resources are summarized in this chapter. ?? 2004 by the American Fisheries Society.

  8. Sustained by First Nations: European newcomers' use of Indigenous plant foods in temperate North America

    Directory of Open Access Journals (Sweden)

    Nancy J. Turner

    2012-12-01

    Full Text Available Indigenous Peoples of North America have collectively used approximately 1800 different native species of plants, algae, lichens and fungi as food. When European explorers, traders and settlers arrived on the continent, these native foods, often identified and offered by Indigenous hosts, gave them sustenance and in some cases saved them from starvation. Over the years, some of these species – particularly various types of berries, such as blueberries and cranberries (Vaccinium spp., wild raspberries and blackberries (Rubus spp., and wild strawberries (Fragaria spp., and various types of nuts (Corylus spp., Carya spp., Juglans spp., Pinus spp., along with wild-rice (Zizania spp. and maple syrup (from Acer saccharum – became more widely adopted and remain in use to the present day. Some of these and some other species were used in plant breeding programs, as germplasm for hybridization programs, or to strengthen a crop's resistance to disease. At the same time, many nutritious Indigenous foods fell out of use among Indigenous Peoples themselves, and along with their lessened use came a loss of associated knowledge and cultural identity. Today, for a variety of reasons, from improving people's health and regaining their cultural heritage, to enhancing dietary diversity and enjoyment of diverse foods, some of the species that have dwindled in their use have been “rediscovered” by Indigenous and non-Indigenous Peoples, and indications are that their benefits to humanity will continue into the future.

  9. Background Mole Fractions of Hydrocarbons in North America Determined from NOAA Global Reference Network Data

    Science.gov (United States)

    Mielke-Maday, I.

    2015-12-01

    The National Oceanic and Atmospheric Administration (NOAA) Global Monitoring Division (GMD) maintains a global reference network for over 50 trace gas species and analyzes discrete air samples collected by this network throughout the world at the Earth System Research Laboratory in Boulder, Colorado. In particular, flask samples are analyzed for a number of hydrocarbons with policy and health relevance such as ozone precursors, greenhouse gases, and hazardous air pollutants. Because this global network's sites are remote and therefore minimally influenced by local anthropogenic emissions, these data yield information about background ambient mole fractions and can provide a context for observations collected in intensive field campaigns, such as the Front Range Air Pollution and Photochemistry Experiment (FRAPPE), the Southeast Nexus (SENEX) study, and the DISCOVER-AQ deployments. Information about background mole fractions during field campaigns is critical for calculating hydrocarbon enhancements in the region of study and for assessing the extent to which a particular region's local emissions sources contribute to these enhancements. Understanding the geographic variability of the background and its contribution to regional ambient mole fractions is also crucial for the development of realistic regulations. We present background hydrocarbon mole fractions and their ratios in North America using data from air samples collected in the planetary boundary layer at tall towers and aboard aircraft from 2008 to 2014. We discuss the spatial and seasonal variability in these data. We present trends over the time period of measurements and propose possible explanations for these trends.

  10. The zebra mussel, Dreissena polymorpha (Pallas, 1771), in North America: impact on raw water users

    Science.gov (United States)

    Griffiths, Ronald W.; Kovalak, William P.; Schloesser, Donald W.

    1989-01-01

    The zebra mussel, Dreissena polymorpha (Pallas), is a small mollusc native to the Black, Caspian, and Azov Seas that was discovered in Lake Erie of the Laurentian Great Lakes of North America in 1988. Its presence there raises immediate concerns for users of raw water because it can become abundant enough to obstruct the flow of water through pipes, hoses, screens, and condensers. Biofouling attributed to this mussel was observed at several power plants, water treatment plants, and food processing and industrial facilities along Lake Erie in 1989. Estimated densities at one power plant intake canal were as high as 700,000 per m2. In addition, large numbers were found in main steam condensors and in the service water system, threatening the water supply for cooling, fire protection, and dust suppression systems. Municipal water intakes along the Canadian and United States shorelines have also been impaired. In one southeast Michigan city, drinking water withdrawal from Lake Erie was reduced 45% by the mussel. Routine checks of raw water supplies for free-floating zebra mussel veligers are reommended to determine if reproducing adult populations are present in local water bodies. After an early alert, raw water intakes could be protected to alleviate damage from the biofouling zebra mussel.

  11. Alternative strategies of seed predator escape by early-germinating oaks in Asia and North America.

    Science.gov (United States)

    Yi, Xianfeng; Yang, Yueqin; Curtis, Rachel; Bartlow, Andrew W; Agosta, Salvatore J; Steele, Michael A

    2012-03-01

    Early germination of white oaks is widely viewed as an evolutionary strategy to escape rodent predation; yet, the mechanism by which this is accomplished is poorly understood. We report that chestnut oak Quercus montana (CO) and white oak Q. alba (WO) (from North America), and oriental cork oak Q. variabilis (OO) and Mongolian oak Q. mongolica (MO) (from Asia) can escape predation and successfully establish from only taproots. During germination in autumn, cotyledonary petioles of acorns of CO and WO elongate and push the plumule out of the cotyledons, whereas OO and MO extend only the hypocotyls and retain the plumule within the cotyledons. Experiments showed that the pruned taproots (>6 cm) of CO and WO acorns containing the plumule successfully germinated and survived, and the pruned taproots (≥12 cm) of OO and MO acorns without the plumule successfully regenerated along with the detached acorns, thus producing two seedlings. We argue that these two distinct regeneration morphologies reflect alternative strategies for escaping seed predation.

  12. Sub-Seafloor Carbon Dioxide Storage Potential on the Juan de Fuca Plate, Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Jerry Fairley; Robert Podgorney

    2012-11-01

    The Juan de Fuca plate, off the western coast of North America, has been suggested as a site for geological sequestration of waste carbon dioxide because of its many attractive characteristics (high permeability, large storage capacity, reactive rock types). Here we model CO2 injection into fractured basalts comprising the upper several hundred meters of the sub-seafloor basalt reservoir, overlain with low-permeability sediments and a large saline water column, to examine the feasibility of this reservoir for CO2 storage. Our simulations indicate that the sub-seafloor basalts of the Juan de Fuca plate may be an excellent CO2 storage candidate, as multiple trapping mechanisms (hydrodynamic, density inversions, and mineralization) act to keep the CO2 isolated from terrestrial environments. Questions remain about the lateral extent and connectivity of the high permeability basalts; however, the lack of wells or boreholes and thick sediment cover maximize storage potential while minimizing potential leakage pathways. Although promising, more study is needed to determine the economic viability of this option.

  13. Meteorological and chemical factors controlling the composition of precipitation in eastern North America

    International Nuclear Information System (INIS)

    Precipitation in eastern North America is characterized by high concentrations of free acidity and sulfate that are generally attributed to anthropogenic air pollution. The relatively long record of precipitation chemistry measurements at the Penn State MAP3S site is used to analyze the seasonal and interannual variability of precipitation composition in terms of specific mechanisms of atmospheric transport and chemical transformation. The interrelationships of the chemical variables in the precipitation record and in recent air measurements clearly link the precipitation acidity with the wet deposition of sulfate derived from the in-cloud oxidation of sulfur dioxide. High-deposition events are shown through meteorological trajectory analyses to be associated with moist air from the Gulf of Mexico that passes through the upper midwestern parts of the United States. The main chemical factor controlling the deposition of sulfate appears to be the availability of strong oxidants for transforming dissolved sulfur dioxide into aqueous sulfate. Excess sulfur dioxide is expected to exit the storm systems at high altitudes and experience truly long-range transport. This interpretation of the data gives confidence that episodes will occur even after sulfur dioxide emissions have been reduced substantially

  14. Changes in Surface Wind Speed over North America from CMIP5 Model Projections and Implications for Wind Energy

    Directory of Open Access Journals (Sweden)

    Sujay Kulkarni

    2014-01-01

    Full Text Available The centennial trends in the surface wind speed over North America are deduced from global climate model simulations in the Climate Model Intercomparison Project—Phase 5 (CMIP5 archive. Using the 21st century simulations under the RCP 8.5 scenario of greenhouse gas emissions, 5–10 percent increases per century in the 10 m wind speed are found over Central and East-Central United States, the Californian Coast, and the South and East Coasts of the USA in winter. In summer, climate models projected decreases in the wind speed ranging from 5 to 10 percent per century over the same coastal regions. These projected changes in the surface wind speed are moderate and imply that the current estimate of wind power potential for North America based on present-day climatology will not be significantly changed by the greenhouse gas forcing in the coming decades.

  15. White-nose syndrome without borders: Pseudogymnoascus destructans infection tolerated in Europe and Palearctic Asia but not in North America.

    Science.gov (United States)

    Zukal, Jan; Bandouchova, Hana; Brichta, Jiri; Cmokova, Adela; Jaron, Kamil S; Kolarik, Miroslav; Kovacova, Veronika; Kubátová, Alena; Nováková, Alena; Orlov, Oleg; Pikula, Jiri; Presetnik, Primož; Šuba, Jurģis; Zahradníková, Alexandra; Martínková, Natália

    2016-01-01

    A striking feature of white-nose syndrome, a fungal infection of hibernating bats, is the difference in infection outcome between North America and Europe. Here we show high WNS prevalence both in Europe and on the West Siberian Plain in Asia. Palearctic bat communities tolerate similar fungal loads of Pseudogymnoascus destructans infection as their Nearctic counterparts and histopathology indicates equal focal skin tissue invasiveness pathognomonic for WNS lesions. Fungal load positively correlates with disease intensity and it reaches highest values at intermediate latitudes. Prevalence and fungal load dynamics in Palearctic bats remained persistent and high between 2012 and 2014. Dominant haplotypes of five genes are widespread in North America, Europe and Asia, expanding the source region of white-nose syndrome to non-European hibernacula. Our data provides evidence for both endemicity and tolerance to this persistent virulent fungus in the Palearctic, suggesting that host-pathogen interaction equilibrium has been established. PMID:26821755

  16. Freshwater fish faunas, habitats and conservation challenges in the Caribbean river basins of north-western South America.

    Science.gov (United States)

    Jiménez-Segura, L F; Galvis-Vergara, G; Cala-Cala, P; García-Alzate, C A; López-Casas, S; Ríos-Pulgarín, M I; Arango, G A; Mancera-Rodríguez, N J; Gutiérrez-Bonilla, F; Álvarez-León, R

    2016-07-01

    The remarkable fish diversity in the Caribbean rivers of north-western South America evolved under the influences of the dramatic environmental changes of neogene northern South America, including the Quechua Orogeny and Pleistocene climate oscillations. Although this region is not the richest in South America, endemism is very high. Fish assemblage structure is unique to each of the four aquatic systems identified (rivers, streams, floodplain lakes and reservoirs) and community dynamics are highly synchronized with the mono-modal or bi-modal flooding pulse of the rainy seasons. The highly seasonal multispecies fishery is based on migratory species. Freshwater fish conservation is a challenge for Colombian environmental institutions because the Caribbean trans-Andean basins are the focus of the economic development of Colombian society, so management measures must be directed to protect aquatic habitat and their connectivity. These two management strategies are the only way for helping fish species conservation and sustainable fisheries. PMID:27401480

  17. Relative influence of human harvest, carnivores, and weather on adult female elk survival across western North America

    Science.gov (United States)

    Brodie, Jedediah; Johnson, Heather; Mitchell, Michael; Zager, Peter; Proffitt, Kelly; Hebblewhite, Mark; Kauffman, Matthew; Johnson, Bruce; Bissonette, John; Bishop, Chad; Gude, Justin; Herbert, Jeff; Hersey, Kent; Hurley, Mark; Lukacs, Paul M.; McCorquodale, Scott; McIntire, Eliot; Nowak, Josh; Sawyer, Hall; Smith, Douglas; White, P.J.

    2013-01-01

    Well-informed management of harvested species requires understanding how changing ecological conditions affect demography and population dynamics, information that is lacking for many species. We have limited understanding of the relative influence of carnivores, harvest, weather and forage availability on elk Cervus elaphus demography, despite the ecological and economic importance of this species. We assessed adult female survival, a key vital rate for population dynamics, from 2746 radio-collared elk in 45 populations across western North America that experience wide variation in carnivore assemblage, harvest, weather and habitat conditions. Proportional hazard analysis revealed that 'baseline' (i.e. not related to human factors) mortality was higher with very high winter precipitation, particularly in populations sympatric with wolves Canis lupus. Mortality may increase via nutritional stress and heightened vulnerability to predation in snowy winters. Baseline mortality was unrelated to puma Puma concolor presence, forest cover or summer forage productivity. Cause-specific mortality analyses showed that wolves and all carnivore species combined had additive effects on baseline elk mortality, but only reduced survival by <2%. When human factors were included, ‘total’ adult mortality was solely related to harvest; the influence of native carnivores was compensatory. Annual total mortality rates were lowest in populations sympatric with both pumas and wolves because managers reduced female harvest in areas with abundant or diverse carnivores. Mortality from native carnivores peaked in late winter and early spring, while harvest-induced mortality peaked in autumn. The strong peak in harvest-induced mortality during the autumn hunting season decreased as the number of native carnivore species increased. Synthesis and applications. Elevated baseline adult female elk mortality from wolves in years with high winter precipitation could affect elk abundance as

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

    Science.gov (United States)

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

    2000-01-01

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

  19. How does the Indian diaspora help drive trade and investment ties between India and North America? An exploratory study

    OpenAIRE

    Chand, Masud Sohail Mohammad

    2009-01-01

    This study examines the role that the Indian diaspora plays in helping to drive trade and investment ties between India on one hand and Canada and the United States on the other. The Indian diaspora is becoming increasingly important in both political and economic terms in North America. As trade and investment ties continue to grow between a fast developing India and Canada and the United States, the Indian diaspora has been playing an important role in driving this relationship. This study ...

  20. Vaccine-induced protection against 3 systemic mycoses endemic to North America requires Th17 cells in mice

    OpenAIRE

    Wüthrich, Marcel; Gern, Benjamin; Hung, Chiung Yu; Ersland, Karen; Rocco, Nicole; Pick-Jacobs, John; Galles, Kevin; Filutowicz, Hanna; Warner, Thomas; Evans, Michael; Cole, Garry; Klein, Bruce

    2016-01-01

    Worldwide rates of systemic fungal infections, including three of the major pathogens responsible for such infections in North America (Coccidioides posadasii, Histoplasma capsulatum, and Blastomyces dermatitidis), have soared recently, spurring interest in developing vaccines. The development of Th1 cells is believed to be crucial for protective immunity against pathogenic fungi, whereas the role of Th17 cells is vigorously debated. In models of primary fungal infection, some studies have sh...