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Based on ERA-interim reanalysis dataset from 1979 to 2018, this study revisits the global and regional water cycle, as well as the water vapor transport between ocean basins. The surface of the Earth is divided into five continents and four ocean basins, water vapor budget, and its seasonal variability of each continent and ocean basin are calculated. The Indian Ocean and the Atlantic are major net water vapor source regions, ~ − 0.47 Sv and ~ −0.82 Sv, respectively, while the Pacific and the Arctic are weak net water vapor sink regions, ~ 0.04 Sv and ~ 0.06 Sv, respectively. A total of 85% of evaporation and 78% of precipitation occur at the ocean-atmosphere interface while 15% of evaporation and 22% of precipitation occur at the land-atmosphere interface. About 1.19 Sv water vapor is carried out from oceans to lands. The water vapor transport is about 0.07 Sv from the Indian Ocean to the Pacific, and 0.22 Sv from the Atlantic to the Pacific through the segments. At low latitudes, both the Atlantic and the Indian Ocean transport water vapor to the Pacific, with a total of 0.29 Sv. Those results update the estimate of global and regional water vapor budget. [ABSTRACT FROM AUTHOR]

The South Asian high (SAH) is a huge anticyclone in the upper troposphere. It influences the climate and the distribution of trace constituents and pollutants. The present study documents the change in the SAH and precipitation under global warming, as well as the possible link between the changes, based on 17 Coupled Model Intercomparison Project Phase 5 (CMIP5) model simulations. The CMIP5 historical simulation reproduces reasonably the tropospheric circulation (including the SAH), precipitation, and moisture. Under global warming, more than 75 % of the CMIP5 models project a southward shift of the SAH. The southward shift is more significant in the models with stronger anticyclonic circulation in the south part of the climatological SAH. The precipitation response displays a contrasting feature: negative over the southeastern equatorial Indian Ocean (IO) and positive over the tropical northern IO, the Bay of Bengal, and the equatorial western Pacific. The results of a linear baroclinic model (LBM) show that the regional rainfall changes over the Bay of Bengal and the equatorial western Pacific have a main contribution to the southward shift of the SAH. In addition, the precipitation and the surface wind responses over the Indo-Pacific region are well coupled. On one hand, the surface wind anomaly affects the rainfall response through altering the SST and moisture. On the other hand, the condensational heating released by regional rainfall changes sustains the surface wind response. [ABSTRACT FROM AUTHOR]