Trends of Land Surface Change from Landsat time-series 1999-2014, Alaska, UTM Zone 4N, 66°N - 68°N (US)

The Hot Spot Regions of Permafrost Change (HRPC) product maps changes in surface characteristics using the full Landsat archive (TM, ETM+, OLI) for the peak summer season (July, August) from 1999 to 2014. The HRPC products provide trends of multi-spectral indices such as Tasselled Cap brightness, greenness, wetness and normalized indices (NDVI, NDWI, NDMI) in 4 regional transects spanning the panarctic permafrost domain. Changes in indices can be linked to both gradual (press disturbance) and rapid (pulse disturbances) land surface changes. Press disturbances are for example shrub expansion, wetting, drying, or active layer deepening. Pulse disturbances include thermokarst and thermo-erosion, lake formation, expansion, and shrinkage, erosion, or wildfires.

All products are spatially organized into three different levels: Transects, Zones and Blocks. HRPC maps are available for four transects: T1 Western Siberia, T2 Eastern Siberia, T3 Alaska, and T4 Eastern Canada. Each transect is subdivided into zones, which correspond to their respective UTM Zones e.g. zones Z051 and Z052 for T2 Eastern Siberia. Due to the large data size, the zones are further subdivided into smaller tiles of 2° latitude (e.g. 64°N to 66°N) and the full width of the UTM zone within the respective transect.

More information on image processing, trend analysis and interpretation can be found in the product guide.