Defenses for Spring 2026

Revisiting the Importance of a Southern Ocean Pattern Effect

February 25, 2026

Killian McSweeney

The spatial pattern of surface warming determines radiative feedbacks (“pattern effect”). The seminal work of Senior & Mitchell (2000) (SM00) argued that Southern Ocean clouds set the evolution of global radiative feedbacks in time and hence, determine climate sensitivity. We revisit their argument in current generation climate models: We quantify the time evolution of local atmospheric…

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…