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Publication Date
28 October 2020

Contrasting Phase Changes of Precipitation Annual Cycle Between Land and Ocean Under Global Warming



We report a land‐ocean contrast in the phase change of precipitation annual cycle in multimodel ensemble simulations as climate warms, with a robust delay over land (0–40°N/S) versus an advance (0–40°N/S) or no clear (0–25°N/S) phase changes over ocean. The robust delay over land is caused by the increased effective atmospheric heat capacity CA. Over ocean, the increased CA favors a phase delay, while the land‐ocean precipitation contrast during the peak rainy season favors a phase advance. The latter overwhelms the former and causes a seasonal advance over 0–40°N/S, while the two factors cancel out and result in no phase changes over 0–25°N/S. Under the atmospheric energetic constraint, the land‐ocean precipitation contrast in the peak rainy season is related to their opposite amplitude changes of surface temperature annual cycle: Seasonally different wind changes enhance the amplitude over ocean, while increased CA and surface cooling feedback reduce the amplitude over land.
“Contrasting Phase Changes Of Precipitation Annual Cycle Between Land And Ocean Under Global Warming”. 2020. Geophysical Research Letters 47. doi:10.1029/2020gl090327.
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