Raster Climate Priming Index and supporting data for Alaska and Northwest Canada 1901-2100

The datasets presented here include the Climate Priming Index, degree-day, and seasonal precipitation data used as inputs to the index for the state of Alaska. The data is presented for two time periods: a historic period from 1901-2020, and a projected period from 2000-2100 using 3 climate scenarios. The climate priming index was developed to identify years where the climatic conditions support the initiation of thermokarst processes in areas of ice-rich permafrost. The Climate Priming Index is comprised of 6 components calculated from cumulative distribution functions based on 5 unique variables: freezing degree-days, thawing degree-days, summer precipitation, early winter precipitation, and total winter precipitation. The Climate Priming Index is based on the previous year's values for each of the unique variables plus the current year's thawing degree-day values. Freezing and thawing degree-days were calculated from monthly data using a piecewise cubic hermite interpolating polynomial. Seasonal precipitation was calculated from monthly data using additional inputs from the polynomial used to calculate the degree-day data.