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 degrees N/S) versus an advance (0-40 degrees N/S) or no clear (0-25 degrees N/S) phase changes over ocean. The robust delay over land is caused by the increased effective atmospheric heat capacity C-A. Over ocean, the increased C-A 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 degrees N/S, while the two factors cancel out and result in no phase changes over 0-25 degrees 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 C-A and surface cooling feedback reduce the amplitude over land.