Filters: Tags: permafrost (X)
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As part of the Department of Natural Resources (DNR) effort to make final recommendations of federal land parcels to be considered for selection by the State of Alaska according to provisions of the Statehood Act, a decision was made to identify and evaluate potential access corridors. Corridor maps were compiled for a total of 78 quadrangles throughout Alaska. This map suite shows relevant geologic information at a scale of 1:250,000 for 10-mile-wide corridors straddling centerlines for proposed access routes throughout Alaska. The maps are based on geologic data compiled from existing, published mapping. Each compiled corridor geology map was used to derive maps of potential construction materials, data quality,...
During 2009, the Alaska Division of Geological & Geophysical Surveys continued a program, begun in 2006, of reconnaissance mapping of surficial geology in the proposed natural-gas pipeline corridor through the upper Tanana River valley. The study area is a 12-mi-wide (19.3-km-wide) area that straddles the Alaska Highway from the western boundaries of the Tanacross B-3 and A-3 quadrangles near Tetlin Junction eastward to the eastern boundaries of the Nabesna D-1 and C-1 quadrangles along the Canada border. Mapping during 2008-2009 in the Tanacross and Nabesna quadrangles linked with the mapping completed in the Tanacross, Big Delta and Mt. Hayes quadrangles in 2006-2008. Surficial geology was initially mapped in...
This release contains Active Layer Thickness (ALT) and Organic Layer Thickness (OLT) measurements measured along transects in Alaska, 2015. Site condition information in terms of wildfire burns is also included.
Categories: Data;
Types: Citation;
Tags: Active layer,
Active layer thickness,
Alaska,
Borehole nuclear magnetic resonance,
Chatanika,
Vector line dataset displaying the extent of sea ice and subsea permafrost in the northern hemisphere. This is a companion dataset to the Circum-Arctic Map of Permafrost and Ground Ice Conditions .
The "MasterDB-csv-final2" dataset includes 548 laboratory measurements of sediment total mercury (STHg, nanograms per gram of soil, dry), bulk density (BD, grams per cm3 of soil, dry), percent of soil organic matter (%OM, loss on ignition, LOI), percent of soil organic carbon (%SOC, calculated using the Redfield's number), RHgC (Hg to carbon ratio), and age (YBP) from 13 permafrost cores collected from 2004 to 2012 in the interoir and northern slope of Alaska by trained personnel from the U.S. Geological Survey National Research Program and the National Snow and Ice Data Center in Boulder, Colorado.
This map illustrates extents and types of unconsolidated deposits and bedrock in the Big Delta A-4 Quadrangle, Alaska. This map is based on field observations begun by P�w� in 1949 and by Reger in 1976. Unit characteristics and extents were determined during field visits and by interpreting 1:40,000-scale black-and-white aerial photographs taken in August 1949 and 1:63,360-scale, false-color infrared aerial photographs taken in July 1978, August 1980, and August 1981.
Abstract (from http://onlinelibrary.wiley.com/doi/10.1111/gcb.12875/abstract): Permafrost thaw can alter the soil environment through changes in soil moisture, frequently resulting in soil saturation, a shift to anaerobic decomposition, and changes in the plant community. These changes, along with thawing of previously frozen organic material, can alter the form and magnitude of greenhouse gas production from permafrost ecosystems. We synthesized existing methane (CH 4) and carbon dioxide (CO 2) production measurements from anaerobic incubations of boreal and tundra soils from the geographic permafrost region to evaluate large-scale controls of anaerobic CO 2 and CH 4 production and compare the relative importance...
Categories: Publication;
Types: Citation;
Tags: Alaska CASC,
Alaska CASC,
Glaciers and Permafrost,
Water, Coasts and Ice,
anaerobic incubation,
Our objective is to improve the scientific understanding of the modes, rates, and mechanisms of carbon stabilization and losses in soils from Alaska, California, and other Western states. We focus on the biophysical and microbial mechanisms that drive carbon gains and losses, and to use our data to improve models of soil carbon cycling. This catalog supports research from several projects focused on soil carbon cycling. It encompasses multiple types of datasets including environmental, ecological, biological, isotopic, mineralogical, genomic, flux, and modeled data from water, vegetation, soil, and atmospheric matrices. The catalog will be available online and to the public. Therefore, publication of data through...
Some of the YKL rasters intentionally do not align or have the same extent. These rasters were not snapped to a common raster per the authors' discretion. Please review selected rasters prior to use. These varying alignments are a result of the use of differing source data sets and all products derived from them. We recommend that users snap or align rasters as best suits their own projects. - This file includes a downscaled projection of decadal Active Layer Thickness and Seasonally Frozen Layer Thickness (m) for the decade 2020-2029 at 2km spatial resolution, using the A2 emissions scenario. The raster contains both negative and positive values. Positive values relate to the active layer thickness, or depth of...
The RTK survey, using a Trimble unit, was conducted in August 2021 in the coastal plains region (1002 area) of the Arctic National Wildlife Refuge, as part of a landscape vulnerability assessment. A total of six transects are included in the data, including five research sites and one transect collected at the camp site. Mean horizontal precision was 0.006m, mean vertical precision was 0.011m.
Categories: Data;
Tags: Arctic,
Arctic National Wildlife Refuge,
Climatology,
Geography,
Geomorphology,
Surface-based 2D electrical resistivity tomography (ERT) surveys were used to investigate the distribution of permafrost at wetland sites on the alluvial plain north of the Tanana River, 20 km southwest of Fairbanks, Alaska, in June and September 2014. The sites contained habitat types characteristic of interior Alaska, including thermokarst bog, forested permafrost plateau, and a rich fen. These habitats range from treed to open and vary in groundcover vegetation and peat thickness. Individual surveys used a cable with 56 electrodes at 2-m spacing. At a fen site, ERT surveys were performed across a mixed spruce forest area across a vegetation gradient into an open fen area. At a bog site,surveys were performed...
Alaska permafrost characterization: Borehole Nuclear Magnetic Resonance (NMR) data collected in 2021
Geophysical measurements were collected by the U.S. Geological Survey (USGS) at five sites in Interior Alaska in September 2021 for the purposes of imaging permafrost structure and quantifying variations in subsurface moisture content in relation to thaw features. Borehole nuclear magnetic resonance (NMR) data were collected at two sites in order to determine liquid water content at depth in shallow boreholes. NMR data were collected in a 2.25 m-deep borehole at the North Star golf course adjacent to one of the ERT profiles, and in another two 1.625 m-deep boreholes adjacent to Big Trail Lake where previous NMR measurements were made in 2019 and 2020.
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Active layer thickness,
Alaska,
Bonanza Creek,
Borehole nuclear magnetic resonance,
Disturbance,
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...
Categories: Data,
Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: ACTIVE LAYER,
Academics & scientific researchers,
CRYOSPHERE,
Data Acquisition and Development,
Data Management and Integration,
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.
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 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.
Map of the Fish and Judy Creek Area and location of proposed observation sites (numbered circles). Fish Creek, Judy Creek, and the Ublutuoch River are almost entirely within the Beaufort Coastal Plain Ecoregion, though a small portion of Judy Creek extends into the Brooks Foothills. Inset shows the location of the seven TEON focal watersheds. Image by Arctic LCC staff.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: AIR TEMPERATURE,
AIR TEMPERATURE,
ATMOSPHERE,
ATMOSPHERE,
Academics & scientific researchers,
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...
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.
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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