Pliocene equatorial temperature: Lessons from atmospheric superrotation

  • Tziperman E
  • Farrell B
  • 42

    Readers

    Mendeley users who have this article in their library.
  • 20

    Citations

    Citations of this article.

Abstract

There is proxy evidence that the pronounced east-west temperature difference observed today across the equatorial Pacific Ocean may not have existed in the early Pliocene (4-5 Ma {BP)} and that the east Pacific cold tongue developed gradually toward the end of the Pliocene (2 Ma {BP).} The east Pacific temperature influences weather and climate worldwide, and the Pliocene climate may be an instructive analogue to a future warm climate arising from anthropogenic elevation of {CO{\textless}SUB{\textgreater}2{\textless}/SUB{\textgreater}}, making understanding the Pliocene equatorial {SST} gradient especially relevant. A mechanism for maintaining a weaker Pliocene equatorial temperature gradient is proposed that borrows from theories of atmospheric superrotation. The mechanism is based on enhanced or rearranged tropical convective activity during the warmer Pliocene climate exciting atmospheric Rossby waves that propagated poleward from the equator. These waves produced an equatorward flux of westerly momentum that weakened the surface easterlies and therefore the east-west thermocline slope and {SST} gradient.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Eli Tziperman

  • Brian Farrell

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free