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Information on the nature and distribution of permafrost is critical to assessing the response of Arctic ecosystems to climate change, because thawing permafrost under a warming climate will cause thaw settlement and affect micro-topography, surface water redistribution and groundwater movement, soil carbon balance, trace gas emissions, vegetation changes, and habitat use. While a small-scale regional permafrost map is available, as well as information from numerous site-specific large-scale mapping projects, landscape-level mapping of permafrost characteristics is needed for regional modeling and climate impact assessments. The project addresses this need by: (1) compiling existing soil/permafrost data from available...
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Permafrost peatlands store one-third of the total carbon (C) in the atmosphere and are increasingly vulnerable to thaw as high-latitude temperatures warm. Large uncertainties remain about C dynamics following permafrost thaw in boreal peatlands. We used a chronosequence approach to measure C stocks in forested permafrost plateaus (forest) and thawed permafrost bogs, ranging in thaw age from young (<10 years) to old (>100 years) from two interior Alaska chronosequences. Permafrost originally aggraded simultaneously with peat accumulation (syngenetic permafrost) at both sites. We found that upon thaw, C loss of the forest peat C is equivalent to ~30% of the initial forest C stock and is directly proportional to the...
Categories: Publication; Types: Citation; Tags: Global Change Biology
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Information on the nature and distribution of permafrost is critical to assessing the response of Arctic ecosystems to climate change, because thawing permafrost under a warming climate will cause thaw settlement and affect micro-topography, surface water redistribution and groundwater movement, soil carbon balance, trace gas emissions, vegetation changes, and habitat use. While a small-scale regional permafrost map is available, as well as information from numerous site-specific large-scale mapping projects, landscape-level mapping of permafrost characteristics is needed for regional modeling and climate impact assessments. The project addresses this need by: (1) compiling existing soil/permafrost data from available...
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The western coast of Alaska is a remote region, rich in wildlife and providing critical nesting habitat for many of Alaska’s seabirds. It is also home to indigenous communities who rely upon the region’s natural resources to support a traditional lifestyle of hunting, gathering, and fishing. Although the region is frequently subject to extensive inland flooding from Bering Sea storms, little is known about the extent and frequency of flooding and its impacts on vegetation, wildlife, and water quality. Furthermore, information is lacking about how climate change and sea-level rise (which can influence the frequency and intensity of storms and subsequent flooding) are affecting this area, its communities, and their...
Information on the nature and distribution of permafrost is critical to assessing the response of Arctic ecosystems to climate change, because thawing permafrost under a warming climate will cause thaw settlement and affect micro-topography, surface water redistribution and groundwater movement, soil carbon balance, trace gas emissions, vegetation changes, and habitat use. While a small-scale regional permafrost map is available, as well as information from numerous site-specific large-scale mapping projects, landscape-level mapping of permafrost characteristics is needed for regional modeling and climate impact assessments. The project addresses this need by: (1) compiling existing soil/permafrost data from available...
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Information on the nature and distribution of permafrost is critical to assessing the response of Arctic ecosystems to climate change, because thawing permafrost under a warming climate will cause thaw settlement and affect micro-topography, surface water redistribution and groundwater movement, soil carbon balance, trace gas emissions, vegetation changes, and habitat use. While a small-scale regional permafrost map is available, as well as information from numerous site-specific large-scale mapping projects, landscape-level mapping of permafrost characteristics is needed for regional modeling and climate impact assessments. The project addresses this need by: (1) compiling existing soil/permafrost data from available...
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We measured surface elevations, stage of annual peak flooding, and sedimentation along 10 toposequences across coastal ecosystems on the Yukon-Kuskokwim (Y-K) Delta in western Alaska during 1994-1998 to assess some of the physical processes affecting ecosystem distribution. An ecotype was assigned to each of 566 points, and differences in elevations among 24 ecotypes were analyzed within individual toposequences and across the 40 x 40-km study area. Elevations of vegetated ecotypes along the longest toposequence rose only ~1 m over a distance of 7.5 km, and mean elevations of most ecotype across the study area were within 0.5 m of mean higher-high water (1.47 m). During 1994 to 1998, monitoring of annual peak stage...
Categories: Publication; Types: Citation; Tags: Journal of Coastal Research
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Major ecosystems have been mapped and described for the State of Alaska and nearby areas. Ecoregion units are based on newly available datasets and field experience of ecologists, biologists, geologists and regional experts. Recently derived datasets for Alaska included climate parameters, vegetation, surficial geology and topography. Additional datasets incorporated in the mapping process were lithology, soils, permafrost, hydrography, fire regime and glaciation. Thirty two units are mapped using a combination of the approaches of Bailey (hierarchial), and Omernick (integrated). The ecoregions are grouped into two higher levels using a 'tri-archy' based on climate parameters, vegetation response and disturbance...
Categories: Publication; Types: Citation; Tags: Open-File Report
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We used a modeling framework and a recent ecological land classification and land cover map to predict how ecosystems and wildlife habitat in northwest Alaska might change in response to increasing temperature. Our results suggest modest increases in forest and tall shrub ecotypes in Northwest Alaska by the end of this century thereby increasing habitat for forest-dwelling and shrub-using birds and mammals. Conversely, we predict declines in several more open low shrub, tussock, and meadow ecotypes favored by many waterbird, shorebird, and small mammal species.
Categories: Publication; Types: Citation; Tags: Alaska Park Science
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Information on the nature and distribution of permafrost is critical to assessing the response of Arctic ecosystems to climate change, because thawing permafrost under a warming climate will cause thaw settlement and affect micro-topography, surface water redistribution and groundwater movement, soil carbon balance, trace gas emissions, vegetation changes, and habitat use. While a small-scale regional permafrost map is available, as well as information from numerous site-specific large-scale mapping projects, landscape-level mapping of permafrost characteristics is needed for regional modeling and climate impact assessments. The project addresses this need by: (1) compiling existing soil/permafrost data from available...
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The Western Alaska LCC, the Department of Interior’s Alaska Climate Science Center​ and the Bureau of Land Management brought together 150 land and resource managers, field specialists, researchers and local knowledge experts to identify climate change related priority science/information needs for land and resource management in western Alaska. The workshop results help inform development of the LCC’s Science Strategy, which will guide the LCC’s efforts over the next ten years. The workshop was modeled in part after the 2007 WildREACH Workshop for the arctic region. Attendance was by invitation; workshop organizers sought diverse cross-program and cross-agency participation.
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Deep soil profiles containing permafrost (Gelisols) were characterized for organic carbon (C) and total nitrogen (N) stocks to 3m depths. Using the Community Climate System Model (CCSM4) we calculate cumulative probability functions (PDFs) for active layer depths under current and future climates. The difference in PDFs over time was multiplied by C and N contents of soil horizons in Gelisol suborders to calculate newly thawed C and N, Thawing ranged from 147 PgC with 10 PgN by 2050 (representative concentration pathway RCP scenario 4.5) to 436 PgC with 29 PgN by 2100 (RCP 8.5). Organic horizons that thaw are vulnerable to combustion, and all horizon types are vulnerable to shifts in hydrology and decomposition....


    map background search result map search result map Modeling Future Storm Impacts on the Yukon-Kuskokwim Delta Predicting the effects of climate change on ecosystems and wildlife habitat in northwest Alaska: results from the WildCast project Permafrost Database Development, Characterization, and Mapping for Northern Alaska Shared Science Needs: Western AK LCC Science Workshop Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska Modeling Future Storm Impacts on the Yukon-Kuskokwim Delta Predicting the effects of climate change on ecosystems and wildlife habitat in northwest Alaska: results from the WildCast project Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska Shared Science Needs: Western AK LCC Science Workshop