BCD-ME: Bias-Corrected and Downscaled Massive Ensemble

Projections of climate change and climate impacts requires bias-corrected, downscaled output from ensembles of earth system models (ESMs). Potential impacts are uncertain due to modeling differences between ESMs, internal variability stemming from the chaos of the earth system, and differences in the historical reference datasets used to bias-corrected and downscale ESM output. The Bias-Corrected and Downscaled Massive Ensemble (BCD-ME) is a multi-model large ensemble of over 1,400 projections of daily mean and maximum temperature. The BCD-ME samples model and internal uncertainty with up to 86 runs from 12 Large Ensembles (LEs; and single runs from 10 further ESMs) and uncertainty in the reference dataset by using 4 different reanalysis products to bias-correct and downscale output. Output is organized by Global Warming Levels (GWL), accounting for differences between forcing scenarios and ESM climate sensitivities, or by 20-year chunks. The ensemble contains 20-year daily time series for each GWL on a uniform 1-degree grid, bias-corrected using Quantile Delta Mapping, statistics of 20-year time series for each GWL on a uniform 0.25-degree grid, downscaled using Quantile-Preserving Localized Analog Downscaling. The BCD-ME also includes a set of 20-year daily time series of model output run on SSP3-7.0, but organized by model calendar year, for comparison with GWL-based data.