Western U.S. lake expansions during Heinrich stadials linked to Pacific Hadley circulation.

ABSTRACT: Lake and cave records show that winter precipitation in the southwestern United States increased substantially during millennial-scale periods of Northern Hemisphere winter cooling known as Heinrich stadials. However, previous work has not produced a clear picture of the atmospheric circulation changes driving these precipitation increases. Here, we combine data with model simulations to show that maximum winter precipitation anomalies were related to an intensified subtropical jet and a deepened, southeastward-shifted Aleutian Low, which together increased atmospheric river-like transport of subtropical moisture into the western United States. The jet and Aleutian Low changes are tied to the southward displacement of the intertropical convergence zone and the accompanying intensification

SUBMITTER: McGee D 

PROVIDER: S-EPMC6261653 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature