Unexpected Warming From Land Radiative Management

Abstract

“Land radiative management” (LRM)—deliberately increasing surface albedo to decrease temperatures—has been proposed as a form of geoengineering to mitigate the effects of regional warming. Here, we show that, contrary to expectations, LRM causes temperatures to increase in surrounding regions. The basic reason for the increase is unintended impacts on precipitation. Precipitation is suppressed over the LRM region, but this effect also extends to nearby areas unprotected by LRM. The reduction in precipitation and soil moisture in these regions leads to higher temperatures than would be expected in the absence of LRM. The resulting warming outside the LRM region is comparable to the cooling achieved inside it. This implies that, if wealthy regions unilaterally adopt LRM to cool, their neighbors may experience warming, worsening heat inequality.