Super recovery of the Hadley Cell edge to the CO2 removal

Abstract

<jats:p>&amp;lt;p&amp;gt;The poleward shift of the Hadley cell (HC) edge by global warming is widely documented. However, its reversibility to CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; removal remains unknown. By conducting a climate model experiment where CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; concentration is systematically increased and then decreased in time, this study shows that a poleward-shifted HC edge in warm climate returns equatorward as CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; concentration decreases. It is also shown that the rate significantly differs between the two hemispheres. While the southern HC edge monotonically changes with CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; concentration, the northern HC edge exhibits a super recovery, locating on the equatorward side of the present-climate HC edge when CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; concentration returns to the present level. Such a super recovery is associated with the hysteresis of the North Atlantic sea surface temperature. Our findings suggest that the HC edge change may result in the super recovery of subtropical dryness in the northern hemisphere except California.&amp;lt;/p&amp;gt;</jats:p>