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Active Layer Thickness 2040 2049

Dates

Last Update
2015-11-02
Publication Date
2011-09-29

Citation

LCC Network Data Steward(Point of Contact), Arctic Landscape Conservation Cooperative(administrator), 2015-11-02(lastUpdate), 2011-09-29(Publication), Active Layer Thickness 2040 2049, http://arcticlcc.org/products/84adfa0c-dd56-4915-9308-5ef938bec327, https://www.sciencebase.gov/catalog/item/5a300c6ce4b08e6a89d57f22

Summary

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 frozen and the cell [...]

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ActiveLayerThickness_2040_2049.zip 1.56 MB
md_metadata.json 228.45 KB
metadata.xml
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1.28 MB

Material Request Instructions

Arctic Landscape Conservation Cooperative(Data Owner)

Purpose

The Geophysical Institute Permafrost Lab (GIPL) model was developed specifically to assess the effect of a changing climate on permafrost. The GIPL 1.0 model is a quasi-transitional, spatially distributed, equilibrium model for calculating the active layer thickness and mean annual ground temperature. The GIPL-1 model accounts effectively for the effects of snow cover, vegetation, soil moisture, and soil thermal properties. The GIPL-1 model allows for the calculation of maximum active layer thickness (ALT) and mean annual ground temperatures (MAGT) at the bottom of the active layer. The approach to determine the ALT and MAGT is based on an approximate analytical solution that includes freezing/thawing processes and provides an estimation of thermal offset due to the difference in frozen and thawed soil thermal properties (Kudryavtsev, et al., 1974). It uses the idea of applying the Fourier temperature wave propagation theory to a medium with phase transitions, such as freezing/thawing ground. Application of this approach resulted in the discovery of the thermal offset and an understanding of the laws that govern the dynamics of the ground thermal regime. These discoveries led to an understanding of the effects that the thermal properties of the ground have upon the MAGTs and ALT, and how periodically (seasonally) varying climatic parameters affect permafrost dynamics. The output parameters of this method are given as annual averages.

Additional Information

Identifiers

Type Scheme Key
urn:uuid urn:uuid 84adfa0c-dd56-4915-9308-5ef938bec327

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