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Probabilistic estimates of the distribution of near-surface (within 1m) permafrost in Alaska.
This medium resolution (i.e. 30-m pixels) spatial dataset provides an estimate of the occurrence of near-surface (within 1 m of the ground surface) permafrost in Alaska. The dataset was developed using a decision-tree model that statistically and spatially extended late-season field observations (n ~ 17,000) using remotely sensed imagery, climatic data, and thematic maps of a wide range of surface and subsurface biophysical characteristics. To circumvent the use of seasonal frost observations, only thaw-depth measurements taken during late-season months (late July to mid-September) or measurements designated to have no near-surface (within 1m) permafrost were used for model calibration and validation. Individual pixel values represent the probability of encountering near-surface permafrost (i.e. 0 to 100 %), as derived from a tree ensemble model, and pixel values greater than 100 correspond to masked land cover types (i.e. 101 = open water; 102 = perennial ice/snow; 103 = developed; 104 = barren, and; 105 = cultivated areas) as defined by the 2001 National Land Cover Database. Decision tree models and resultant maps were tested using independent field observations and f-fold cross validations, which indicated that the map product has an overall accuracy of approximately 85 % when using a probability threshold of 50 % (i.e. less than 50 % = near-surface permafrost absent; greater than or equal to 50 % = near-surface permafrost present).
| Author(s) | Neal J. Pastick, Bruce K. Wylie, M. Torre Jorgenson, Shawn J. Nield, Kristofer D. Johnson, Andrew O. Finley |
| Publication Date | 2015-07-31 |
| Beginning Date of Data | 2001 |
| Ending Date of Data | 2010 |
| Data Contact | |
| DOI | http://dx.doi.org/10.5066/F7C53HX6 |
| Citation | Pastick, N.J., Wylie, B.K., Jorgenson, M.T., Nield, S.J., Johnson, K.D., and Finley, A.O., 2015, Probabilistic estimates of the distribution of near-surface (within 1m) permafrost in Alaska.: U.S. Geological Survey data release, http://dx.doi.org/10.5066/F7C53HX6. |
| Metadata Contact | |
| Metadata Date | 2020-08-18 |
| Related Publication | There was no related primary publication associated with this data release. |
| Citations of these data | No citations of these data are known at this time. |
| Access | public |
| License | http://www.usa.gov/publicdomain/label/1.0/ |
Harvest Date: 2024-07-05T04:03:10.086Z