Physical Explanation for Paradoxical Climate Change in Semi-Arid Inland Eurasia Based on a Remodeled Precipitation Recycling Ratio and Clausius–Clapeyron Equation

Abstract

Under global warming, the climate in semi-arid inland Eurasia (SAIE) has changed in an opposite manner, thereby seriously impacting the local ecological environment. However, the key influencing factors and physical mechanism remain inconclusive. In this paper, we remodel the precipitation recycling ratio (PRR) model to assess the contributions of moisture from different water vapor sources to local precipitation, analyze the characteristics of the PRR and precipitation in SAIE, and provide possible physical reasons based on the Clausius–Clapeyron equation. It is found that the PRR increased from 1970 to 2017 as the result of linear trend analysis, with obvious seasonality. Moreover, the component of precipitation contributed by locally evaporated moisture (Pl), and that contributed by advected moisture (Pa) as well as the total precipitation (P), increased during the past 48 years. In particular, the Pa, Pl, and P in autumn and winter all increased obviously during the past 20 years from the interdecadal change trend, as well as the PRR (Pl/P), which was opposite to the decrease in the total water vapor input I(Ω) in the horizontal direction. According to the Clausius–Clapeyron equation, one of the causes might be that global warming has accelerated the local water cycle and driven the increase in Pa, and the increase in atmospheric water holding capacity caused by global warming provides the power source. We suggest that the climate’s transformation from dry to wet in SAIE can only be temporary since SAIE is an inland area and the adjustment of atmospheric circulation did not lead to the increase in external water vapor.

Projected near-future changes in precipitation extremes over Anambra-Imo River Basin inferred from CMIP6 HighResMIP

“…Diba et al, [54] reported that the intensi cation of precipitation over West Africa is related to the warm extremes. According to the Clausius-Clapeyron equation, global warming has accelerated the local water cycle and increased advected moisture, leading to the intensi cation in precipitation extremes [55].…”

Climate Change and Its Impacts on Terrestrial Ecosystems: Recent Advances and Future Directions

“…Wang et al [5] partitioned the total precipitation into two components (namely, the local evaporation and external water vapor advection) and revised the precipitation recycling ratio model, which is used to assess the contributions of moisture from different water vapor sources to local precipitation in semi-arid inland Eurasia. It was found that the precipitation recycling ratio increased from 1970 to 2017, with obvious seasonality in this region.…”