Defenses for Spring 2026

Contextualizing Past and Future Mean Southwest U.S. Precipitation with Marine Heatwaves

February 04, 2026

Olivia Lee

As the Southwest U.S. (SWUS) grapples with continued drought and increased water scarcity, paleoclimate analyses suggest the SWUS was wetter during past warm climates such as the Pliocene. One hypothesis for a wetter SWUS in the Pliocene is that warmer eastern Pacific sea surface temperature (SST) during the Pliocene enhanced North American Monsoon precipitation. Similarly, warmer California…