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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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The Nurek cluster is named for the Nurek Dam and Reservoir along the Vakhsh River in Tadjikistan. The cluster includes several earthquakes in the low-5 magnitude range. Most of the seismicity appears to be associated with the reservoir and some of the seismicity may have been induced by the filling of the reservoir. It is notable that the the period 1999-2010 produced no earthquakes large enough to be included in the cluster. Number of events: 43 Calibration type: direct calibration using data to 1.2 degrees; hypocentroid calibration level = 1.2 km Epicentral calibration range: 2 - 5 km Date...
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The purpose of this project is to provide better information to industry and regulatory agencies regarding the likely locations of polar bear dens. This project integrates snow physics, high-resolution digital elevation data, and bear biology to produce more refined and accurate maps predicting suitable polar bear den habitat than are currently available. The work consists of data gathering, consultation between snow and bear scientists, modeling, and sensitivity studies to understand the various factors influencing den location and evolution along the Beaufort Coast.The proposed work is intended to refine current methods of identifying polar bear denning sites by incorporating higher-resolution topographic data...
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TheNorthSlopeofAlaskaliesonthenorthsideofBrooksRangeandincludesextensivecoastlinesalongtheChukchiSeaandBeaufortSea.TheseshorelinesarefundamentallydifferentfrommostofthecoastlineintheUSastheyareconsolidatedbypermafrostandsubjecttoperiglacialprocesses,includingcryogenicprocessesonshoreandnearshoreseasonalpackiceformation.ThesecoastsarehighlydynamicandundergoingsomeofthefastestretreatratesinNorthAmerica(GibbsandRichmondn.d.).Proposedoffshoreoildevelopmentactivitiesinthe ChukchiSeacoastandexistingoffshoredrillingislandsalongtheBeaufortSeacoastposeenvironmentalrisksforthesecoasts.Environmentalconcernsincludeincreasedairandseatraffic,accidentaloilspills,andpotentialportdevelopments.BOEMrequiresup-­‐to-­‐date,digitalmappingthatcanbeusedtosystematicallyassesstheseenvironmentalrisks.TheSh...
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The Wildlife Conservation Society will assess the climate change vulnerability of bird species that regularly breed in substantial populations in Alaska using the NatureServe Climate Change Vulnerability Index (CCVI) tool. Initial work will focus on breeding birds in Arctic Alaska including shorebirds, waterfowl and waterbird species (loons, gulls, terns, jaegers), and land bird species (passerines, raptors, ptarmigan).
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Contemporary observations suggest that water may disappear entirely from portions of some North Slope stream-beds during periods of drought or low flow. Climate models project even drier summers in the future. This could pose a problem for migrating fish that must be able to move back and forth from breeding and summer feeding areas to scarce overwintering sites. This work uses the best available long-term hydrologic data set for the North Slope (in the upper Kuparuk River watershed) to develop a model to assess the vulnerability of stream systems to periodic drought, and the vulnerability of migrating fish to a loss of stream connectivity.
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Baseline (1961-1990) average winter temperature in and projected change in temperature for for the northern portion of Alaska. For the purposes of these maps, ‘winter’ is defined as December - February. The Alaska portion of the Arctic LCC’s terrestrial boundary is depicted by the black line. Baseline results for 1961-1990 are derived from Climate Research Unit (CRU) TS3.1 data and downscaled to 2km grids; results for the other time periods (2010-2039, 2040-2069, 2070-2099) are based on the SNAP 5-GCM composite using the AR5-RCP 8.5, downscaled to 2km grids.
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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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Watersheds draining the Arctic Coastal Plain (ACP) of Alaska are dominated by permafrostand snowmelt runoff that create abundant surface storage in the form of lakes, wetlands, and beaded streams. These surface water elements compose complex drainage networks that affect aquatic ecosystem connectivity and hydrologic behavior. The 4676 km2 Fishand Creek drainage basin is composed of three watersheds that represent a gradient of theACP landscape with varying extents of eolian, lacustrine, and fluvial landforms. In each watershed, we analyzed 2.5-m-resolution aerial photography, a 5-m digital elevationmodel, and river gauging and climate records to better understand ACP watershed structureand processes. We show that...
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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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Stream physical parameter time series files for six or more beaded streams on the North Slope of Alaska in the Fish Creek Watershed near Nuiqsut. These include time series of water temperature (pool bed and surface and channel runs) and pool stage and correspond stream discharge developed from a rating curve.
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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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More than 35,000 lakes larger than 0.01 sq. km. were extracted from an airborne interferometric synthetic aperture radar (IfSAR) derived digital surface model acquired between 2002 and 2006 for the Western Arctic Coastal Plain of northern Alaska. The IfSAR derived lake data layer provides an improvement over previously available datasets for the study area since it is more comprehensive and contemporary. Attributes assigned to the IfSAR-derived lake dataset include: area, lake elevation, elevation in 10, 25, 50, and 100 m buffers around a lake perimeter, the difference in elevation between the lake and these various buffers, whether a particular lake had a detectable drainage gradient exceeding 1.2 m, whether a...
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Water availability, distribution, quality and quantity are critical habitat elements for fish and other water-dependent species. Furthermore, the availability of water is also a pre-requisite for a number of human activities. The density of weather and hydrology observation sites on the North Slope is orders of magnitude less than in other parts of the U.S., making it difficult to document hydrologic trends and develop accurate predictive models where water is a key input. The information that does exist is scattered among many entities, and varies in format. This multi-year data rescue effort project brings together these scarce and scattered hydrology data sets, including high-priority datasets held by the Bureau...
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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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The Arctic Tern completes annual epic migrations from pole to pole covering at least 40,000 kmon their round-trip journeys. They breed throughout Arctic Alaska from boreal to tundra habitatsand have their highest nesting densities inland (Lensink 1984). Arctic Terns typically choose nestsites on open ground near water and often on small islands in ponds and lakes (Hatch 2002).Arctic terns consume a wide variety of fish and invertebrate prey, fish are particularly importantduring the breeding season for feeding young (Hatch 2002). This species spends their winters(austral summers) in offshore waters near Antarctica (Hatch 2002). Alaskan Arctic Coastal Plainpopulation estimates from 2011 range from 7-12,000 (Larned...
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This dataset includes Snow Free Date(sfdy) for northern Alaska in GeoTiff format, covering the years 1980-2012. Snow Free Date is defined as day of the end of the core snow period(day of year). The core snow season is defined to be the longest period of continuous snow cover in each year. The dataset was generated by the Arctic LCC SNOWDATA: Snow Datasets for Arctic Terrestrial Applications project.“Day-of-year” (doy) output is expressed in Ordinal dates (“1” on 1 January, and “365” on 31 December). Dates have not been corrected for leap years. This output is appropriate for display purposes, as it is readily interpreted as calendar day of year. It is not recommended as input for analysis, as it may produce incorrect...
Categories: Data; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: AIR TEMPERATURE, AIR TEMPERATURE, ALBEDO, ALBEDO, Academics & scientific researchers, All tags...
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The Red-necked Phalarope commonly breeds in both the Brooks Range foothills and ArcticCoastal Plain of Alaska. In Alaska, this species typically nests in wet tundra near water’s edge.It differs from the Red Phalarope in that it breeds further inland and at higher elevations (Rubegaet al. 2000). Like other phalaropes, this species depends on aquatic food sources for much of itsdiet (Rubega et al. 2000). Red-necked Phalaropes spend winter at sea in tropical waters in largenumbers off the west coast of South America (Rubega et al. 2000). Current North Americanpopulation estimate is 2.5 million with a declining trend (Morrison et al. 2006).


map background search result map search result map Mapping Suitable Snow Habitat for Polar Bear Denning Along the Beaufort Coast of Alaska Linking North Slope Climate, Hydrology, and Fish Migration SNOWDATA GeoTIFF Annual Snow Free Date (year) Western Arctic Coastal Plain, IfSAR DSM Mosaic Footprint Linking North Slope of Alaska climate, hydrology, and fish migration North Slope Coastal Imagery Initiative IEM-CSC Factsheet with Supplement, 2015 HydroClimate Data Rescue Factsheet Active Layer Thickness 2040 2049 Drainage Network Structure and Hydrologic Behavior of Three Lake-Rich Watersheds on the Arctic Coastal Plain, Alaska Red-necked Phalarope Fish/Judy Creek Watershed map Fish Creek Watershed Data Annual Temperature Maps - RCP 6.0, Fahrenheit Climate Change Vulnerability of Migrating Bird Species Breeding in Arctic Alaska Historical Stand Age 1870-1879 Historical Stand Age 1900-1909 Arctic Tern Anaktuvuk River Fire Monitoring Tadjikistan, Nurek: 1966-2018 Anaktuvuk River Fire Monitoring Mapping Suitable Snow Habitat for Polar Bear Denning Along the Beaufort Coast of Alaska Linking North Slope Climate, Hydrology, and Fish Migration Linking North Slope of Alaska climate, hydrology, and fish migration Tadjikistan, Nurek: 1966-2018 Drainage Network Structure and Hydrologic Behavior of Three Lake-Rich Watersheds on the Arctic Coastal Plain, Alaska Fish Creek Watershed Data Western Arctic Coastal Plain, IfSAR DSM Mosaic Footprint Fish/Judy Creek Watershed map Red-necked Phalarope Climate Change Vulnerability of Migrating Bird Species Breeding in Arctic Alaska Arctic Tern North Slope Coastal Imagery Initiative HydroClimate Data Rescue Factsheet SNOWDATA GeoTIFF Annual Snow Free Date (year) IEM-CSC Factsheet with Supplement, 2015 Active Layer Thickness 2040 2049 Historical Stand Age 1870-1879 Historical Stand Age 1900-1909 Annual Temperature Maps - RCP 6.0, Fahrenheit