Value addition in coupled model intercomparison project phase 6 over phase 5: global perspectives of precipitation, temperature and soil moisture fields

This study establishes the improvements in the sixth phase of the Coupled Model Intercomparison Project (CMIP6) simulations as compared to its previous version, CMIP5. First, the historical simulations are compared with the reanalysis products from the 5th generation European Centre for Medium-Range Weather Forecasts (ERA5). Quality improvement in CMIP6 is assured through its correspondence with ERA5 in terms of mean, standard deviation and mean bias. Global fields of three hydrometeorological variables, i.e. temperature, precipitation and soil moisture, are considered from multiple General Circulation Models. Among the three variables, maximum improvement is noticed in case of soil moisture followed by precipitation, especially in the tropical belt. In case of temperature, the mean bias has reduced by±3 °C across the parts of North America, Africa, and South Asia. Better reliance on the CMIP6 motivates for a trend analysis to peek into the future. The results indicate a significant increasing trend for precipitation in the temperate, polar and sub-polar regions, whereas a significant increase in temperature is noticed almost all across the world with highest slope in the polar and sub-polar regions. Furthermore, soil moisture shows a significant trend that can be grouped continent-wise, e.g. Africa, Central and South Asia exhibit an increasing trend, whereas North and Central America and Northern parts of South America exhibit an overall decreasing trend. Apart from underlining the better reliance on CMIP6, the findings of this study will also be useful across different parts of the world for many climate related studies using CMIP6.

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Opracowanie rekordu ze środków MEiN, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2022-2023).