Description of the China global Merged Surface Temperature version 2.0

[摘要] Global surface temperature observational datasets are thebasis of global warming studies. In the context of increasing global warmingand frequent extreme events, it is essential to improve the coverage andreduce the uncertainty in global surface temperature datasets. The Chinaglobal Merged Surface Temperature Interim version (CMST-Interim) is updatedto CMST 2.0 in this study. The previous CMST datasets were created bymerging the China global Land Surface Air Temperature (C-LSAT) with seasurface temperature (SST) data from the Extended Reconstructed Sea SurfaceTemperature version 5 (ERSSTv5). The CMST 2.0 contains three variants:CMST 2.0  −  Nrec (without reconstruction), CMST 2.0  −  Imax, and CMST 2.0  −  Imin(according to their reconstruction area of the air temperature over the seaice surface in the Arctic region). The reconstructed datasets significantlyimprove data coverage, whereas CMST 2.0  −  Imax and CMST 2.0  −  Imin have improvedcoverage in the Northern Hemisphere, up to more than 95 %, and thusincreased the long-term trends at global, hemispheric, and regional scalesfrom 1850 to 2020. Compared to CMST-Interim, CMST 2.0  −  Imax and CMST 2.0  −  Iminshow a high spatial coverage extended to the high latitudes and are moreconsistent with a reference of multi-dataset averages in the polar regions.The CMST 2.0 datasets presented here are publicly available at the website offigshare, https://doi.org/10.6084/m9.figshare.16929427.v4 (Sun and Li, 2021a), and the CLSAT2.0 datasets can bedownloaded at https://doi.org/10.6084/m9.figshare.16968334.v4 (Sun and Li, 2021b). Both are also available at http://www.gwpu.net (last access: January 2022).

[学科分类] 眼科学