Bias-corrected NESM3 global dataset for dynamical downscaling under 1.5 °C and 2 °C global warming

Dynamical downscaling is an important approach to generating climate projections at a finer scale. Recently, a set of future simulations under four types of 1.5 and 2 °C global warming scenarios are available using the Nanjing University Information Science and Technology Earth System Model (NESM), which provide a new opportunity for accessing the climate impacts of 1.5 °C/2 °C global warming. However, the systematic bias of the NESM3 in the large-scale driving variables would degrade the dynamical downscaling simulation. With the aid of a novel bias correction method of the global climate model, we corrected the NESM3 bias in terms of climate mean and inter-annual variance against the European Centre for Medium-Range Weather Forecasts Reanalysis 5 dataset and then produced a set of bias-corrected datasets for dynamical downscaling. The bias-corrected NESM3 spans the historical period from 1979 to 2014 and four future scenarios (i.e., 1.5 °C overshoot from 2070 to 2100, stabilized 1.5 °C/2 °C from 2070 to 2100, and transient 2 °C from 2031 to 2061) with a horizontal grid spacing of (1.25° × 1.25°) at six-hourly intervals. Our evaluation suggests that the bias-corrected NESM3 shows better performance in terms of the climatological mean, inter-annual variability, and climate extreme events compared with the original NESM3 during the historical period. This bias-corrected dataset will provide high-quality large-scale driving fields for dynamical downscaling under 1.5 °C and 2 °C global warming scenarios, which is expected to generate more reliable projections for regional climate and environment.