Recent Declines in Warming and Vegetation Greening Trends Over Pan-Arctic Tundra
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Beaufort Sea Monitoring Program
Outer Continental Shelf Environmental Assessment Program Beaufort Sea Monitoring Program: Proceedings of a Workshop and Sampling Design Recommendations Beaufort Sea Monitoring Program: Proceedings of a Workshop (September 1983) and Sampling Design Recommendations ; Prepared for the Outer Continental Shelf Environmental Assessment Program Juneau, Alaska by J. P. Houghton Dames & Moore 155 N.E. lOOth Street Seattle, WA 98125 with D. A Segar J. E. Zeh SEAM Ocean Inc. Department of Statistics Po. Box 1627 University of Washington Wheaton, MD 20902 Seattle, WA 98195 April 1984 UNITED STATES UNITED STATES DEPARTMENT OF COMMERCE DEPARTMENT OF THE INTERIOR Malcolm Baldridge, Secretary William P Clark, Secretary NATIONAL OCEANIC AND MINERALS MANAGEMENT SERVICE ATMOSPHERIC ADMINISTRATION William D. Bettenberg, Director John V. Byrne, Administrator r. NOTICES i? I This report has been reviewed by the US. Department of Commerce, National Oceanic and Atmospheric Administration's Outer Continental Shelf Environmental Assessment Program office, and approved for publication. The interpretation of data and opinions expressed in this document are those of the authors and workshop participants. Approval does not necessarily signify that the contents reflect the views and policies of the Department of Commerce or those of the Department of the Interior. The National Oceanic and Atmospheric Administration (NOAA) does not approve, recommend, or endorse any proprietary product or proprietary material mentioned in this publica tion. No reference shall be made to NOAA or to this publication in any advertising or sales promotion which would indicate or imply that NOAA approves, recommends, or endorses any proprietary'product or proprietary material mentioned herein, or which has as its purpose an intent to cause directly or indirectly the advertised product to be used or purchas'ed because of this publication. -
Meltwater Routing and the Younger Dryas
Meltwater routing and the Younger Dryas Alan Condrona,1 and Peter Winsorb aClimate System Research Center, Department of Geosciences, University of Massachusetts, Amherst, MA 01003; and bInstitute of Marine Science, School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK 99775 Edited by James P. Kennett, University of California, Santa Barbara, CA, and approved September 27, 2012 (received for review May 2, 2012) The Younger Dryas—the last major cold episode on Earth—is gen- to correct another. A separate reconstruction of the drainage erally considered to have been triggered by a meltwater flood into chronology of North America by Tarasov and Peltier (8) found the North Atlantic. The prevailing hypothesis, proposed by Broecker that rather than being to the east, the geographical release point of et al. [1989 Nature 341:318–321] more than two decades ago, sug- meltwater to the ocean at this time might have been toward the gests that an abrupt rerouting of Lake Agassiz overflow through Arctic. Further support for a northward drainage route has since the Great Lakes and St. Lawrence Valley inhibited deep water for- been provided by Peltier et al. (9). Using a numerical model, the mation in the subpolar North Atlantic and weakened the strength authors showed that the response of the AMOC to meltwater of the Atlantic Meridional Overturning Circulation (AMOC). More re- placed directly over the North Atlantic (50° N to 70° N) and the cently, Tarasov and Peltier [2005 Nature 435:662–665] showed that entire Arctic Ocean were almost identical. This result implies that meltwater could have discharged into the Arctic Ocean via the meltwater released into the Arctic might be capable of cooling the Mackenzie Valley ∼4,000 km northwest of the St. -
Baffin Bay Sea Ice Extent and Synoptic Moisture Transport Drive Water Vapor
Atmos. Chem. Phys., 20, 13929–13955, 2020 https://doi.org/10.5194/acp-20-13929-2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Baffin Bay sea ice extent and synoptic moisture transport drive water vapor isotope (δ18O, δ2H, and deuterium excess) variability in coastal northwest Greenland Pete D. Akers1, Ben G. Kopec2, Kyle S. Mattingly3, Eric S. Klein4, Douglas Causey2, and Jeffrey M. Welker2,5,6 1Institut des Géosciences et l’Environnement, CNRS, 38400 Saint Martin d’Hères, France 2Department of Biological Sciences, University of Alaska Anchorage, 99508 Anchorage, AK, USA 3Institute of Earth, Ocean, and Atmospheric Sciences, Rutgers University, 08854 Piscataway, NJ, USA 4Department of Geological Sciences, University of Alaska Anchorage, 99508 Anchorage, AK, USA 5Ecology and Genetics Research Unit, University of Oulu, 90014 Oulu, Finland 6University of the Arctic (UArctic), c/o University of Lapland, 96101 Rovaniemi, Finland Correspondence: Pete D. Akers ([email protected]) Received: 9 April 2020 – Discussion started: 18 May 2020 Revised: 23 August 2020 – Accepted: 11 September 2020 – Published: 19 November 2020 Abstract. At Thule Air Base on the coast of Baffin Bay breeze development, that radically alter the nature of rela- (76.51◦ N, 68.74◦ W), we continuously measured water va- tionships between isotopes and many meteorological vari- por isotopes (δ18O, δ2H) at a high frequency (1 s−1) from ables in summer. On synoptic timescales, enhanced southerly August 2017 through August 2019. Our resulting record, flow promoted by negative NAO conditions produces higher including derived deuterium excess (dxs) values, allows an δ18O and δ2H values and lower dxs values. -
Ecological Consequences of Sea-Ice Decline Eric Post Et Al
SPECIALSECTION 31. K. B. Ritchie, Mar. Ecol. Prog. Ser. 322,1–14 (2006). 52. C. Moritz, R. Agudo, Science 341, 504–508 (2013). 71. A. J. McMichael, Proc. Natl. Acad. Sci. U.S.A. 109, 32. B. Humair et al., ISME J. 3, 955–965 (2009). 53. C. D. Thomas et al., Nature 427, 145–148 4730–4737 (2012). 33. D. Corsaro, G. Greub, Clin. Microbiol. Rev. 19,283–297 (2006). (2004). 72. T. Wheeler, J. von Braun, Science 341, 508–513 34. W. Jetz et al., PLoS Biol. 5, e157 (2007). 54. Intergovernmental Panel on Climate Change, Summary (2013). 35. B. J. Cardinale et al., Nature 486,59–67 (2012). for Policymakers. Climate Change 2007: The Physical 73. S. S. Myers, J. A. Patz, Annu. Rev. Environ. Resour. 34, 36. P. T. J. Johnson, J. T. Hoverman, Proc. Natl. Acad. Sci. U.S.A. Science Basis. Contribution of Working Group I to the Fourth 223–252 (2009). 109,9006–9011 (2012). Assessment Report of the Intergovernmental Panel on 74. C. A. Deutsch et al., Proc. Natl. Acad. Sci. U.S.A. 105, 37. F. Keesing et al., Nature 468, 647–652 (2010). Climate Change (Cambridge Univ. Press, New York, 2007). 6668–6672 (2008). 38. P. H. Hobbelen, M. D. Samuel, D. Foote, L. Tango, 55. S. Laaksonen et al., EcoHealth 7,7–13 (2010). D. A. LaPointe, Theor. Ecol. 6,31–44 (2013). 56. O. Gilg et al., Ann. N. Y. Acad. Sci. 1249, 166–190 (2012). Acknowledgments: This work was supported in part by an NSF 39. T. -
Thesis Paleo-Feedbacks in the Hydrological And
THESIS PALEO-FEEDBACKS IN THE HYDROLOGICAL AND ENERGY CYCLES IN THE COMMUNITY CLIMATE SYSTEM MODEL 3 Submitted by Melissa A. Burt Department of Atmospheric Science In partial fulfillment of the requirements for the Degree of Master of Science Colorado State University Fort Collins, Colorado Summer 2008 COLORADO STATE UNIVERSITY April 29, 2008 WE HEREBY RECOMMEND THAT THE THESIS PREPARED UNDER OUR SUPERVISION BY MELISSA A. BURT ENTITLED PALEO-FEEDBACKS IN THE HYDROLOGICAL AND ENERGY CYCLES IN THE COMMUNITY CLIMATE SYSTEM MODEL 3 BE ACCEPTED AS FULFILLING IN PART REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE. Committee on Graduate work ________________________________________ ________________________________________ ________________________________________ ________________________________________ ________________________________________ Adviser ________________________________________ Department Head ii ABSTRACT OF THESIS PALEO FEEDBACKS IN THE HYDROLOGICAL AND ENERGY CYCLES IN THE COMMUNITY CLIMATE SYSTEM MODEL 3 The hydrological and energy cycles are examined using the Community Climate System Model version 3 (CCSM3) for two climates, the Last Glacial Maximum (LGM) and Present Day. CCSM3, developed at the National Center for Atmospheric Research, is a coupled global climate model that simulates the atmosphere, ocean, sea ice, and land surface interactions. The Last Glacial Maximum occurred 21 ka (21,000 yrs before present) and was the cold extreme of the last glacial period with maximum extent of ice in the Northern Hemisphere. During this period, external forcings (i.e. solar variations, greenhouse gases, etc.) were significantly different in comparison to present. The “Present Day” simulation discussed in this study uses forcings appropriate for conditions before industrialization (Pre-Industrial 1750 A.D.). This research focuses on the joint variability of the hydrological and energy cycles for the atmosphere and lower boundary and climate feedbacks associated with these changes at the Last Glacial Maximum. -
Consensus Statement
Arctic Climate Forum Consensus Statement 2020-2021 Arctic Winter Seasonal Climate Outlook (along with a summary of 2020 Arctic Summer Season) CONTEXT Arctic temperatures continue to warm at more than twice the global mean. Annual surface air temperatures over the last 5 years (2016–2020) in the Arctic (60°–85°N) have been the highest in the time series of observations for 1936-20201. Though the extent of winter sea-ice approached the median of the last 40 years, both the extent and the volume of Arctic sea-ice present in September 2020 were the second lowest since 1979 (with 2012 holding minimum records)2. To support Arctic decision makers in this changing climate, the recently established Arctic Climate Forum (ACF) convened by the Arctic Regional Climate Centre Network (ArcRCC-Network) under the auspices of the World Meteorological Organization (WMO) provides consensus climate outlook statements in May prior to summer thawing and sea-ice break-up, and in October before the winter freezing and the return of sea-ice. The role of the ArcRCC-Network is to foster collaborative regional climate services amongst Arctic meteorological and ice services to synthesize observations, historical trends, forecast models and fill gaps with regional expertise to produce consensus climate statements. These statements include a review of the major climate features of the previous season, and outlooks for the upcoming season for temperature, precipitation and sea-ice. The elements of the consensus statements are presented and discussed at the Arctic Climate Forum (ACF) sessions with both providers and users of climate information in the Arctic twice a year in May and October, the later typically held online. -
New Facts and Additional Information Supporting the Cop16
NOVEMBER 2012 NRDC ISSUE PAPER IP:12-11-A New Facts and Additional Information Supporting the CoP16 Polar Bear Proposal Submitted by the United States of America About NRDC NRDC (Natural Resources Defense Council) is a national nonprofit environmental organization with more than 1.3 million members and online activists. Since 1970, our lawyers, scientists, and other environmental specialists have worked to protect the world’s natural resources, public health, and the environment. NRDC has offices in New York City, Washington, D.C., Los Angeles, San Francisco, Chicago, Montana, and Beijing. Visit us at www.nrdc.org. NRDC’s policy publications aim to inform and influence solutions to the world’s most pressing environmental and public health issues. For additional policy content, visit our online policy portal at www.nrdc.org/policy. NRDC Director of Communications: Phil Gutis NRDC Deputy Director of Communications: Lisa Goffredi NRDC Policy Publications Director: Alex Kennaugh Lead Editor: Design and Production: www.suerossi.com Cover photo © Paul Shoul: paulshoulphotography.com © Natural Resources Defense Council 2012 n October 4, 2012, the United States, supported by the Russian Federation, submitted a proposal to transfer the polar bear, Ursus maritimus, from OAppendix II to Appendix I of the Convention in accordance with Article II and Resolution Conf. 9.24 (Rev. CoP15) on the basis that the polar bear is affected by trade and shows a marked decline in the population size in the wild, which has been inferred or projected on the basis of a decrease in area of habitat and a decrease in quality of habitat. Pursuant to the Convention, “Appendix I shall include all species threatened with extinction which are or may be affected by trade.” CITES Article II, paragraph 1. -
AMAP Update on Selected Climate Issues of Concern: Observations, Short-Lived Climate Forcers, Arctic Carbon Cycle, and Predictive Capability
DRAFT: FOR RESTRICTED CIRCULATION FOR REVIEW PURPOSES ONLY. DO NO CITE, COPY OR DISTRIBUTE Version approved by AMAP WG, 14 January 2009 AMAP Update on Selected Climate Issues of Concern: Observations, Short-lived Climate Forcers, Arctic Carbon Cycle, and Predictive Capability EXECUTIVE SUMMARY C1. The Arctic Climate Impact Assessment and the Intergovernmental Panel on Climate Change have established the importance of climate change in the Arctic both regionally and globally. Following those reports, emphasis has been placed on continued observations, a new assessment of the Arctic carbon cycle, the role of short lived climate forcers in the Arctic, and the need for improved predictive capacity at the regional level in the Arctic. C2. The Arctic continues to warm. Since publication of the Arctic Climate Impact Assessment in 2005, several indicators show further and extensive climate change at rates faster than previously anticipated. Air temperatures are increasing in the Arctic. Sea ice extent has decreased sharply, with a record low in 2007 and ice-free conditions in both the Northeast and Northwest sea passages for first time in recorded history in 2008. As ice that persists for several years (multi- year ice) is replaced by newly formed (first-year) ice, the Arctic sea-ice is becoming increasingly vulnerable to melting. Surface waters in the Arctic Ocean are warming. Permafrost is warming and, at its margins, thawing. Snow cover in the Northern Hemisphere is decreasing by 1-2% per year. Glaciers are shrinking and the melt area of the Greenland Ice Cap is increasing. The treeline is moving northwards in some areas up to 3-10 meters per year, and there is increased shrub growth north of the treeline. -
From Africa to Eurasia * Early Dispersals Ofer Bar-Yosef! *, A
Quaternary International 75 (2001) 19}28 From Africa to Eurasia * early dispersals Ofer Bar-Yosef! *, A. Belfer-Cohen" !Department of Anthropology, Peabody Museum, Harvard University, Cambridge, MA 02138, USA "Institute of Archaeology, Hebrew University, Jerusalem 91905, Israel Abstract The dispersals of early hominins in the late Pliocene or early Pleistocene into Eurasia were essentially sporadic. Little geographic and temporal continuity is observed between the various dated archaeological contexts, and the lithic assemblages do not demonstrate a techno-morphological continuity. The archaeological evidence from 1.8 to 0.7 Ma indicates at least three waves of early migrations. The earliest sortie involved bearers of core-chopper industries sometime around 1.7}1.6 Ma. Early Acheulean producers followed possibly around 1.4 Ma. The third wave occurred sometime around 0.8 Ma, and is represented by Acheulean groups who manufactured numerous #ake cleavers. The geographic scope of each of these waves is not yet well known.The reasons for &why' early humans dispersed from Africa into Eurasia include the &push' of environmental change and relative &demographic pressure', as well as the opening of new niches. Humans may have gained their meat supplies either from carcasses or through active predation. The archaeological and fossil records demonstrate that Homo erectus was a successful species, and like other successful species it enlarged its geographic distribution at all costs. Even if the trigger for the initial dispersal of Homo erectus remains unknown or controversial, the success of the hominid occupation of the Eurasian habitats was not primarily facilitated by the availability of food, or the human #exibility in food procuring techniques, but by the absence of the zoonotic diseases that plagued and constrained hominins in their African &cradle of evolution'. -
Sediment Transport to the Laptev Sea-Hydrology and Geochemistry of the Lena River
Sediment transport to the Laptev Sea-hydrology and geochemistry of the Lena River V. RACHOLD, A. ALABYAN, H.-W. HUBBERTEN, V. N. KOROTAEV and A. A, ZAITSEV Rachold, V., Alabyan, A., Hubberten, H.-W., Korotaev, V. N. & Zaitsev, A. A. 1996: Sediment transport to the Laptev Sea-hydrology and geochemistry of the Lena River. Polar Research 15(2), 183-196. This study focuses on the fluvial sediment input to the Laptev Sea and concentrates on the hydrology of the Lena basin and the geochemistry of the suspended particulate material. The paper presents data on annual water discharge, sediment transport and seasonal variations of sediment transport. The data are based on daily measurements of hydrometeorological stations and additional analyses of the SPM concentrations carried out during expeditions from 1975 to 1981. Samples of the SPM collected during an expedition in 1994 were analysed for major, trace, and rare earth elements by ICP-OES and ICP-MS. Approximately 700 h3freshwater and 27 x lo6 tons of sediment per year are supplied to the Laptev Sea by Siberian rivers, mainly by the Lena River. Due to the climatic situation of the drainage area, almost the entire material is transported between June and September. However, only a minor part of the sediments transported by the Lena River enters the Laptev Sea shelf through the main channels of the delta, while the rest is dispersed within the network of the Lena Delta. Because the Lena River drains a large basin of 2.5 x lo6 km2,the chemical composition of the SPM shows a very uniform composition. -
Archaeology Resources
Archaeology Resources Page Intentionally Left Blank Archaeological Resources Background Archaeological Resources are defined as “any prehistoric or historic district, site, building, structure, or object [including shipwrecks]…Such term includes artifacts, records, and remains which are related to such a district, site, building, structure, or object” (National Historic Preservation Act, Sec. 301 (5) as amended, 16 USC 470w(5)). Archaeological resources are either historic or prehistoric and generally include properties that are 50 years old or older and are any of the following: • Associated with events that have made a significant contribution to the broad patterns of our history • Associated with the lives of persons significant in the past • Embody the distinctive characteristics of a type, period, or method of construction • Represent the work of a master • Possess high artistic values • Present a significant and distinguishable entity whose components may lack individual distinction • Have yielded, or may be likely to yield, information important in history These resources represent the material culture of past generations of a region’s prehistoric and historic inhabitants, and are basic to our understanding of the knowledge, beliefs, art, customs, property systems, and other aspects of the nonmaterial culture. Further, they are subject to National Historic Preservation Act (NHPA) review if they are historic properties, meaning those that are on, or eligible for placement on, the National Register of Historic Places (NRHP). These sites are referred to as historic properties. Section 106 requires agencies to make a reasonable and good faith efforts to identify historic properties. Archaeological resources may be found in the Proposed Project Area both offshore and onshore. -
Global Climate Influencer – Arctic Oscillation
ARCTIC OSCILLATION GLOBAL CLIMATE INFLUENCER by James Rohman | February 2014 Figure 1. A satellite image of the jet stream. Figure 2. How the jet stream/Arctic Oscillation might affect weather distribution in the Northern Hemisphere. Arctic Oscillation Introduction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