28 February 2019

Contributions of Interdecadal Pacific Oscillation and Atlantic Multidecadal Oscillation to Global Ocean Heat Content Distribution

Science

Regional sea surface temperature (SST) mode variabilities, especially the La Niña-like Pacific Ocean temperature pattern known as the negative phase of the Interdecadal Pacific Oscillation (IPO), and the associated heat redistribution within the ocean are the leading mechanisms explaining the recent global warming hiatus. Here we use the Community Earth System Model (CESM) version 1, to examine how different phases of two leading decadal timescale SST modes, namely the IPO and the Atlantic Multidecadal Oscillation (AMO), contribute to heat redistribution in the global ocean in the absence of time evolving external forcings.

Impact

  

Summary
  • Our results show that both IPO and AMO can modulate the ocean heat content distribution.
  • The major influence of IPO is in the Pacific basin, and the major influence of AMO is in the Atlantic with significant impact to other basins in association to AMOC.
  • IPO can induce a seesaw-like heat content change between the surface and subsurface oceans.
  • AMO will, in general, induce heat content change with the same sign up to 1500m depth.
Contact
Aixue Hu
National Center for Atmospheric Research (NCAR)