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Past cooling events in the Northern Hemisphere have been shown to impact the location of the intertropical convergence zone (ITCZ) and therewith induce a southward shift of tropical precipitation. Here we use high resolution coupled ocean-atmosphere simulations to show that reasonable past melt rates of the Antarctic Ice Sheet can similarly have led to shifts of the ITCZ, albeit in opposite direction, through large-scale surface air temperature changes over the Southern Ocean. Through sensitivity experiments employing slightly negative to large positive meltwater fluxes, we deduce that meridional shifts of the Hadley cell and therewith the ITCZ are, to a first order, a linear response to Southern Hemisphere high-latitude surface air temperature changes and Antarctic Ice Sheet melt rates. This highlights the possibility to use past episodes of anomalous melt rates to better constrain a possible future response of low latitude precipitation to continued global warming and a shrinking Antarctic Ice Sheet.

Plain Language Summary Changes in high-latitude climate can impact the tropical regions through so-called atmospheric and oceanic teleconnections. Research has mostly focused on past southward shifts in the band of heavy tropical precipitation, called the intertropical convergence zone (ITCZ), linked to large-scale cooling in the Northern Hemisphere resulting from large-scale continental ice sheet buildup or a slowdown of the large-scale Atlantic meridional ocean cirucalation. Here we use high resolution climate simulations to show that melting of the Antarctic Ice Sheet can similarly lead to northward shifts of the ITCZ and the displacement of the accompanying rain belt. Future melt rates of the Antarctic Ice Sheet are highly uncertain, but our work shows that it might have a nonnegligible impact on the tropical climate. Moreover, we find that because of the apparent linearity of the system under consideration, studying episodes of past changes in the size of the Antarctic Ice Sheet can help us constrain the possible changes in the low latitude hydroclimate.