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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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The Gyrfalcon, the largest falcon, is an iconic bird of the circumpolar arctic and subarctic. Thisspecies nests primarily on precipitous cliff faces and typically utilizes nests built by other species(particularly Common Raven, Golden Eagle, and Rough-legged Hawk) (Booms et al. 2008).Gyrfalcon main prey includes bird species ranging in size from passerines to geese whileptarmigan are the preferred prey. Although not well documented, in winter this species movessouth throughout Canada and sometimes into the northern lower 48. Current population on theNorth Slope (tundrius subspecies) is estimated at 250 breeding pairs (USFWS 2000).
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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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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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The Geographic Information Network for Alaska will complete uniform and consistent ecological mapping of the North Slope region and provide a summary of existing field site ecological descriptions (including photos) in a web based environment. Existing automated field information and photos that have reliable geolocation information will be compiled and entered in a web based geographic display based on the ecological mapping.
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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 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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Point file of planetary nomenclature features and attributes
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Almost all the pictures acquired by Mariner 10 that were used for mapping were obtained during the first encounter: those covering the southeast half of the quadrangle are incoming close-encounter images, and those covering the north-west corner are outoing close-encounter images. At the time the pictures were obtained, the terminator was at about long 7° to 8°, within the eastern part of the quadrangle. A large gap in coverage between in the incoming and outgoing images appears as a northeast-trending diagonal blank strip on the base map. A small part of this gap was filled in the southwestern part of the quadrangle by very poor second-encounter images.
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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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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, Arctic Landscape Conservation Cooperative data.gov, All tags...
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This dataset includes Snow Depth(snod) for northern Alaska in GeoTiff format, covering the years 1980-2012. Snow Depth is defined as depth on 1 March(m). The dataset was generated by the Arctic LCC SNOWDATA: Snow Datasets for Arctic Terrestrial Applications project.The dataset is delivered in the ZIP archive file format. Each year is output in a separate GeoTiff file, where the year is indicated by the filename.Over the last 20 years, under a variety of NOAA, NSF, and NASA research programs, a snow-evolution modeling system has been developed that includes the MicroMet micrometeorological model, the SnowModel snow-process model, and the SnowAssim data assimilation model. These modeling tools can be thought of as...
Categories: Data; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: AIR TEMPERATURE, AIR TEMPERATURE, ALBEDO, ALBEDO, Arctic Landscape Conservation Cooperative data.gov, All tags...
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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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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 Pectoral Sandpiper is one of the most abundant breeding birds on the Arctic Coastal Plain ofAlaska. They typically have low nest site fidelity which is likely related to their promiscuousmating strategy, thus nest densities are highly variable from year to year at a given site (Holmesand Pitelka 1998). In Arctic Alaska, primary breeding habitat includes low-lying ponds in a mixof marshy to hummocky tundra and nests are typically placed in slightly raised or better drainedsites (Holmes and Pitelka 1998). Pectoral Sandpipers spend their winters primarily in southernSouth America (Holmes and Pitelka 1998). The current North American population estimate is500,000 and they are believed to be declining (Morrison et...
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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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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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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...


map background search result map search result map Linking North Slope Climate, Hydrology, and Fish Migration SNOWDATA GeoTIFF Annual Snow Free Date (year) Western Arctic Coastal Plain, IfSAR DSM Mosaic Footprint SNOWDATA GeoTIFF Annual Snow Depth 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 Western Arctic Coastal Plain, Coastline and Coastal Features Pectoral Sandpiper Alaska Integrated Ecosystem Model Pilot Year Final Report Fish Creek Watershed Data Ecological Landscapes and Field Site Web-based Tool Potential Evapotranspiration 2040-2049: ECHAM5 - A1B Scenario Gyrfalcon Historical Stand Age 1910-1919 Anaktuvuk River Fire Monitoring Geologic Map of the Victoria Quadrangle of Mercury Anaktuvuk River Fire Monitoring Linking North Slope Climate, Hydrology, and Fish Migration Linking North Slope of Alaska climate, hydrology, and fish migration Fish Creek Watershed Data Western Arctic Coastal Plain, IfSAR DSM Mosaic Footprint Western Arctic Coastal Plain, Coastline and Coastal Features Pectoral Sandpiper Ecological Landscapes and Field Site Web-based Tool Gyrfalcon North Slope Coastal Imagery Initiative HydroClimate Data Rescue Factsheet SNOWDATA GeoTIFF Annual Snow Free Date (year) SNOWDATA GeoTIFF Annual Snow Depth IEM-CSC Factsheet with Supplement, 2015 Active Layer Thickness 2040 2049 Alaska Integrated Ecosystem Model Pilot Year Final Report Potential Evapotranspiration 2040-2049: ECHAM5 - A1B Scenario Historical Stand Age 1910-1919 Geologic Map of the Victoria Quadrangle of Mercury