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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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Arctic grayling (Thymallus arcticus) have a life-history strategy specifically adapted to the extreme climate of the North. These fish migrate to spawning grounds just after breakup in the spring, then migrate to feeding sites in early summer, and finally in the fall migrate back to their overwintering sites. The Kuparuk River is a perennial stream originating in the northern foothills of the Brooks Range on the North Slope of Alaska. Sections of the Kuparuk are periodically intermittent in that, during low flows in the system, these channel reaches appear dry. The flow varies between surface and subsurface in this permafrost-dominated environment, with subsurface flow being limited to the unfrozen thaw bulb around...
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These raster datasets represent historical stand age. The last four digits of the file name specifies the year represented by the raster. For example a file named Age_years_historical_1990.tif represents the year 1990. Cell values represent the age of vegetation in years since last fire, with zero (0) indicating burned area in that year. Files from years 1860-2006 use a variety of historical datasets for Boreal ALFRESCO model spin up and calibration to most closely match historical wildfire dynamics.
This project resulted in an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work provides important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, was known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast was not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of recent...
Categories: Data; Tags: BARRIER ISLANDS, BARRIER ISLANDS, BARRIER ISLANDS, BARRIER ISLANDS, COASTAL AREAS, All tags...
This project resulted in an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work provides important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, was known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast was not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of recent...
Categories: Data; Tags: BARRIER ISLANDS, BARRIER ISLANDS, BARRIER ISLANDS, BARRIER ISLANDS, COASTAL AREAS, All tags...
The YKD is also home to the largest subsistence-based economy in Alaska. Yet, the low-lying landscape mosaic characterizing the YKD is at risk of massive change associated with projected sea level rise (SLR), increasing storm frequency and severity and permafrost degradation due to future climate change. Therefore, to conserve ecosystem services associated with the botanical and faunal richness in the YKD, management strategies in the region should not only be based on current ecosystem conditions, but also incorporate projected changes in landscape composition. The goal of this project is to provide managers and people living in the YKD, an assessment of the vulnerability of the landscape to future change and to...
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These raster datasets represent historical stand age. The last four digits of the file name specifies the year represented by the raster. For example a file named Age_years_historical_1990.tif represents the year 1990. Cell values represent the age of vegetation in years since last fire, with zero (0) indicating burned area in that year. Files from years 1860-2006 use a variety of historical datasets for Boreal ALFRESCO model spin up and calibration to most closely match historical wildfire dynamics.
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Potential Evapotranspiration (PET): These data represent decadal mean totals of potential evapotranspiration estimates (mm). The file name specifies the decade the raster represents. For example, a file named pet_mean_mm_decadal_MPI_ECHAM5_A1B_annual_2000-2009.tif represents the decade spanning 2000-2009. The data were generated by using the Hamon equation and output from ECHAM5, a fifth generation general circulation model created by the Max Planck Institute for Meteorology in Hamburg Germany. Data are at 2km x 2km resolution, and all data are stored in geotiffs. Calculations were performed using R 2.12.1 and 2.12.2 for Mac OS Leopard, and data were formatted into geotiffs using the raster and rgdal packages. Users...
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This raster, created in 2010, is output from the Geophysical Institute Permafrost Lab (GIPL) model and represents simulated active layer thickness (ALT) in meters averaged across a decade. The file name specifies the decade the raster represents. For example, a file named ALT_1980_1989.tif represents the decade spanning 1980-1989. Cell values represent simulated maximum depth (in meters) of thaw penetration (for areas with permafrost) or frost penetration (for areas without permafrost). If the value of the cell is positive, the area is underlain by permafrost and the cell value specifies the depth of the seasonally thawing layer above permafrost. If the value of the cell is negative, the ground is only seasonally...
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This pilot project has initiated a long-term integrated modeling project that aims todevelop a dynamically linked model framework focused on climate driven changes tovegetation, disturbance, hydrology, and permafrost, and their interactions and feedbacks.This pilot phase has developed a conceptual framework for linking current state-of-thesciencemodels of ecosystem processes in Alaska – ALFRESCO, TEM, GIPL-1 – and theprimary processes of vegetation, disturbance, hydrology, and permafrost that theysimulate. A framework that dynamically links these models has been defined and primaryinput datasets required by the models have been developed.
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The Anaktuvuk River Fire was the largest, highest-severity wildfire recorded on Alaska’s North Slope since records began in 1956. The 2007 Anaktuvuk River Fire was an order of magnitude larger than the average fire size in the historic record for northern Alaska and indices of severity were substantially higher than for other recorded tundra burns. An interdisciplinary team assessed fire effects including burn severity, potential plant community shifts, and effects on permafrost and active layers. Observers monumented, photographed, and measured 24 burned and 17 unburned reference transects, starting the year after the fire, and spanning the range of vegetation types and burn severities.
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These raster datasets represent historical stand age. The last four digits of the file name specifies the year represented by the raster. For example a file named Age_years_historical_1990.tif represents the year 1990. Cell values represent the age of vegetation in years since last fire, with zero (0) indicating burned area in that year. Files from years 1860-2006 use a variety of historical datasets for Boreal ALFRESCO model spin up and calibration to most closely match historical wildfire dynamics.
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The Integrated Ecosystem Model is designed to help resource managers understand the nature and expected rate of landscape change. Maps and other products generated by the IEM will illustrate how arctic and boreal landscapes are expected to alter due to climate-driven changes to vegetation, disturbance, hydrology, and permafrost. The products will also provide resource managers with an understanding of the uncertainty in the expected outcomes.
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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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These rasters represent output from the Boreal ALFRESCO (Alaska Frame Based Ecosystem Code) model. Boreal ALFRESCO operates on an annual time step, in a landscape composed of 1 x 1 km pixels, a scale appropriate for interfacing with mesoscale climate and carbon models. The last four digits of the file name specifies the year represented by the raster. For example a file named Age_years_historical_1990.tif represents the year 1990. Cell values represent the age of vegetation in years since last fire, with zero (0) indicating burned area in that year. Coverage of this dataset includes much of the state of Alaska (but does exclude Southeastern AK, Kodiak Island, portions of the Alaska Peninsula, and the Aleutian Islands)....
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This raster, created in 2010, is output from the Geophysical Institute Permafrost Lab (GIPL) model and represents simulated mean annual ground temperature (MAGT) in Celsius, averaged across a decade, at the base of active layer or at the base of the seasonally frozen soil column. The file name specifies the decade the raster represents. For example, a file named MAGT_1980_1989.tif represents the decade spanning 1980-1989. Cell values represent simulated mean annual ground temperature (degree C) at the base of the active layer (for areas with permafrost) or at the base of the soil column that is seasonally frozen (for areas without permafrost). If the value of the cell is negative,the area has permafrost and the...
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This raster, created in 2010, is output from the Geophysical Institute Permafrost Lab (GIPL) model and represents simulated active layer thickness (ALT) in meters averaged across a decade. The file name specifies the decade the raster represents. For example, a file named ALT_1980_1989.tif represents the decade spanning 1980-1989. Cell values represent simulated maximum depth (in meters) of thaw penetration (for areas with permafrost) or frost penetration (for areas without permafrost). If the value of the cell is positive, the area is underlain by permafrost and the cell value specifies the depth of the seasonally thawing layer above permafrost. If the value of the cell is negative, the ground is only seasonally...
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These raster datasets represent historical stand age. The last four digits of the file name specifies the year represented by the raster. For example a file named Age_years_historical_1990.tif represents the year 1990. Cell values represent the age of vegetation in years since last fire, with zero (0) indicating burned area in that year. Files from years 1860-2006 use a variety of historical datasets for Boreal ALFRESCO model spin up and calibration to most closely match historical wildfire dynamics.
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Potential Evapotranspiration (PET): These data represent decadal mean totals of potential evapotranspiration estimates (mm). The file name specifies the decade the raster represents. For example, a file named pet_mean_mm_decadal_CCCMA_CGCM31_A1B_annual_2000-2009.tif represents the decade spanning 2000-2009. The data were generated by using the Hamon equation and output from CCCMA (also CGCM3.1), a third generation coupled global climate model created by the Canadian Centre for Climate Modeling and Analysis. Data are at 2km x 2km resolution, and all data are stored in geotiffs. Calculations were performed using R 2.12.1 and 2.12.2 for Mac OS Leopard, and data were formatted into geotiffs using the raster and rgdal...
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A high spatial resolution storm surge model was developed for the YK Delta area to assess biological impacts of storm surges under current and future climates. Storm surges are expected to be more frequent and more severe in the YK Delta area due to climate change and sea level rise. The biological impacts in the YK Delta due to the changed storm surges could be extreme.The model was assessed with respect to measured water level data at the coast and, where available, spatial extent of inundation, for 6 storms from the period 1992 to 2011. In total, inundation projections from 9 historical storms (5 from the assessment + 4 others) were developed. For each storm, an spatial inundation index (time-integral of water...
Categories: Data; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: ARCHAEOLOGICAL AREAS, ARCHAEOLOGICAL AREAS, Academics & scientific researchers, COASTAL AREAS, COASTAL AREAS, All tags...


map background search result map search result map Linking North Slope of Alaska climate, hydrology, and fish migration Summary handout - Factsheet IEM-CSC Factsheet with Supplement, 2015 Mean Annual Ground Temperature 2060-2069 Stand Age Projections 2080-2089 Active Layer Thickness 2040 2049 Active Layer Thickness 1990-1999 Alaska Integrated Ecosystem Model Pilot Year Final Report Potential Evapotranspiration 2040-2049: ECHAM5 - A1B Scenario Historical Stand Age 1870-1879 Historical Stand Age 1900-1909 Potential Evapotranspiration 2000-2009: CCCMA - A1B Scenario Historical Stand Age 1960-1969 Historical Stand Age 1910-1919 Anaktuvuk River Fire Monitoring Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska Anaktuvuk River Fire Monitoring Linking North Slope of Alaska climate, hydrology, and fish migration Summary handout - Factsheet Permafrost Database Development, Characterization, and Mapping for Northern Alaska Permafrost Database Development, Characterization, and Mapping for Northern Alaska IEM-CSC Factsheet with Supplement, 2015 Mean Annual Ground Temperature 2060-2069 Stand Age Projections 2080-2089 Active Layer Thickness 2040 2049 Active Layer Thickness 1990-1999 Alaska Integrated Ecosystem Model Pilot Year Final Report Potential Evapotranspiration 2040-2049: ECHAM5 - A1B Scenario Historical Stand Age 1870-1879 Historical Stand Age 1900-1909 Potential Evapotranspiration 2000-2009: CCCMA - A1B Scenario Historical Stand Age 1960-1969 Historical Stand Age 1910-1919