Decadal variability of southern subtropical SST wavenumber‐4 pattern and its Impact

Senapati, B. ORCID: https://orcid.org/0000-0001-5029-9731, Dash, M. K. and Behera, S. K. (2022) Decadal variability of southern subtropical SST wavenumber‐4 pattern and its Impact. Geophysical Research Letters, 49 (6). e2022GL099046. ISSN 1944-8007 doi: 10.1029/2022GL099046

Abstract/Summary

A decadal variability is revealed in sea surface temperature (SST) wavenumber-4 (W4) pattern of southern subtropics (20°–55°S) using wavelet and empirical orthogonal function analysis. The decadal variability of the SST W4 pattern evolves from the decadal modulation of the South Pacific Meridional Mode (SPMM) as seen in SST footprints. The SST residuals of the SPMM create a favorable environment for the frequent occurrence of positive/negative type of the SST W4 pattern and is discussed. Since SST W4 pattern covers the globe, it potentially affects the decadal rainfall variability over Southern continents by modulating local atmospheric circulation. During positive phase, anomalous SST close to South America, Australia, and Southern Africa enforces the wind to go on/offshore and converges/diverges the moisture into/out of the landmass. As a result, specific humidity changes and alters the rainfall over Southern continents on a decadal scale. The scenario is opposite during the negative phase.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/118928
Item Type	Article
Refereed	Yes
Divisions	No Reading authors. Back catalogue items Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
Publisher	American Geophysical Union
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