Downscaling climate change projections to Shenandoah National Park, Virginia

Mountainous regions have been shown to be more susceptible to the effects of climate change than adjacent lowlands. In this study, we aim to estimate future changes in maximum temperatures in Shenandoah National Park (SNP), a mountaintop park in the mid-Atlantic home to several endangered species threatened by climate change. We do this using a statistical downscaling technique that uses climate model output from the North American Regional Climate Change Assessment Program (NARCCAP) and temperature lapse rates from the Parameter-elevation Regressions on Independent Slopes Model (PRISM), a high-resolution gridded climate data set. NARCCAP uses boundary conditions from 4 general circulation models to drive 6 regional climate models (RCM) and outputs current (1971-2000) and future (2041-2070) projections to a 50 km spatial resolution over North America. We evaluate downscaled temperatures using data from 61 HOBO ProV2 temperature and humidity sensors deployed along the western (windward) and eastern (leeward) slopes of SNP at elevations ranging ~600 m above mean sea level (lower slope) to ~1100 m above mean sea level (ridgetop). Results show that the downscaled temperatures do not include the observed larger lapse rates in maximum temperature in July, nor do they show the larger lapse rates on the windward slopes compared to the leeward slopes. We improve the downscaling technique and downscale climate projections of maximum temperature to a 1 km spatial resolution.