Climate data for RPA 2020 Assessment: MACAv2 (METDATA) historical modeled (1950-2005) and future (2006-2099) projections for the conterminous United States at the 1/24 degree grid scale

The 2020 Resources Planning Act (RPA) Assessment will include climate change as a driver affecting natural resources on all forest and rangelands in the United States. These climate projections, along with projections for population dynamics, economic growth, and land use change in the United States, comprise the RPA scenarios. The climate scenarios are the Representative Concentration Pathways (RCPs) RCP 4.5 and RCP 8.5 and the downscaled climate data is the MACAv2-METDATA developed by Abatzoglou and Brown (2012) and Abatzoglou (2013). This downscaled climate data set covers the conterminous United States at the grid size of approximately 4 kilometers (1/24 degree) on a side. The data set includes downscaled historical model output (1950-2005) and projections (2006-2099) for both the RCP 4.5 and the RCP 8.5 scenarios for five models: HadGEM2-ES365, MRI-CGCM3, CNRM-CM5, IPSL-CM5A-MR, and NorESM1-M. The variables available include, monthly average of daily mean near-surface specific humidity (huss), mean daily mean potential evapotranspiration (pet), mean daily maximum relative humidity (rhmax), mean daily minimum relative humidity (rhmin), monthly average of daily surface downwelling shortwave radiation (rsds), mean daily maximum air temperature (tasmax), mean daily minimum air temperature (tasmin), and monthly average of daily mean near-surface wind speed (was). With two climate scenarios and five models, ten different climate futures are available.The USDA Forest Service (USFS) produces a periodic assessment of the conditions and trends of the Nation's renewable resources required by the Forest and Rangeland Renewable Resources Planning Act (RPA) of 1974. This RPA Assessment provides a snapshot of current U.S. forest and rangeland conditions and trends on all ownerships, identifies drivers of change, and projects 50 years into the future (https://www.fs.fed.us/research/rpa/, Resources Planning Act (RPA) Assessment). For the 2020 RPA Assessment, the implications of climate change are being analyzed across resource areas. These climate data will support these analyses.Original metadata date was 03/26/2018. Minor metadata updates were made on 03/25/2019 and 07/30/2020. On 01/27/2021 an incorrect URL in the metadata was corrected. Additional minor metadata updates were made on 04/18/2023. Metadata updated on 10/17/2023 to include reference to published document supporting the 2020 RPA Assessment.