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Here we demonstrate that changes of the North Atlantic subtropical high and its regional rainfall pattern during mid-Holocene precessional changes and idealized 4xCO(2) increase can both be understood as a remote response to increased land heating near North Africa. Despite different sources and patterns of radiative forcing (increase in CO2 concentration versus changes in orbital parameters), we find that the pattern of energy, circulation, and rainfall responses in the Northern Hemisphere summer subtropics are remarkably similar in the two forcing scenarios because both are dominated by the same land-sea heating contrast in response to the forcing. An increase in energy input over arid land drives a westward displacement of the coupled North Atlantic subtropical high-monsoon circulation, consistent with increased precipitation in the Afro-Asia region and decreased precipitation in the America-Atlantic region. This study underscores the importance of land heating in dictating remote drying through zonal shifts of the subtropical circulation.

Plain Language Summary Rainfall is a key impact variable when interpreting global change scenarios and distilling the response to an external climate forcing down to regional scales. Here we demonstrate that drying in the North Atlantic region in summer is a common response to increased CO2 and increased insolation scenarios. The pattern of remote rainfall and circulation changes in the North Atlantic occurs independent of the source of forcing, so long as the forcing includes robust energy input over land near North Africa. By highlighting common physical linkages of the climate system, this study helps to unify interpretation of regional rainfall changes across a variety of forcing constraints.