Comparison of a very-fine-resolution GCM with RCM dynamical downscaling in simulating climate in China

Abstract

Regional climate simulation can generally be improved by using an RCM nested within a coarser-resolution GCM. However, whether or not it can also be improved by the direct use of a state-of-the-art GCM with very fine resolution, close to that of an RCM, and, if so, which is the better approach, are open questions. These questions are important for understanding and using these two kinds of simulation approaches, but have not yet been investigated. Accordingly, the present reported work compared simulation results over China from a very-fine-resolution GCM (VFRGCM) and from RCM dynamical downscaling. The results showed that: (1) The VFRGCM reproduces the climatologies and trends of both air temperature and precipitation, as well as inter-monthly variations of air temperature in terms of spatial pattern and amount, closer to observations than the coarse-resolution version of the GCM. This is not the case, however, for the inter-monthly variations of precipitation. (2) The VFRGCM captures the climatology, trend, and inter-monthly variation of air temperature, as well as the trend in precipitation, more reasonably than the RCM dynamical downscaling method. (3) The RCM dynamical downscaling method performs better than the VFRGCM in terms of the climatology and inter-monthly variation of precipitation. Overall, the results suggest that VFRGCMs possess great potential with regard to their application in climate simulation in the future, and the RCM dynamical downscaling method is still dominant in terms of regional precipitation simulation.

Analysis on the Changes of Agro-Meteorological Thermal Indices in Northeast China under RCP4.5 Scenario Using the PRECIS2.1

“…In comparison with the T mean , the T min would warm up more obviously, which is consistent with previous findings [34,36]. Relative to observations, overestimation of the simulated T mean and T min were reproduced in the Lesser Khingan and Changbai mountains, which was also commonplace among GCMs [37]. Discrepancy between models and real conditions could be attributed to climate models' sensitivity to altitude [38].…”

Precipitation over the Tibetan Plateau during recent decades: a review based on observations and simulations

“…land‐surface scheme) need further study. In addition, compared with the coarse‐resolution GCMs, even the very‐fine‐resolution GCMs, of some having resolution less than 50 km, closing to that of an RCM, the high‐resolution RCMs performs better in terms of the spatial distribution and inter‐monthly variation of precipitation (Guo and Wang, ). This physical processes‐based approach, in spite of some flaws, can improve the understanding of the processes that lead to precipitation on the TP (Maussion et al ., ).…”

Comparison between past and future extreme precipitations simulated by global and regional climate models over the Tibetan Plateau

“…Therefore, CORDEX leaves room for the TP to be in the focus. Besides CORDEX, a few regional dynamic downscaling projections over the whole of China and East Asia were reported (Gao et al, 2011b;Xu et al, 2012;Bucchignani et al, 2014;Ji and Kang, 2015;Bao et al, 2015;Yu et al, 2015;Guo and Wang, 2016). Most of them focus on the evaluations and projections of the annual mean surface air temperature and precipitation.…”