Trends in Latent and Sensible Heat Fluxes over the Southern Ocean

Lejiang Yu, Zhanhai Zhang, Mingyu Zhou, Shiyuan Zhong, Donald H. Lenschow, Binrui Li, Xianqiao Wang, Shiming Li, Huiding Wu, Bo Sun

Applied Hydrometeorological Research Institute, Nanjing University of Information Science & Technology, Nanjing, China.
Michigan State University, East Lansing, Michigan, U.S.A..
National Center for Atmospheric Research, Boulder, U.S.A.
National Marine Environment Forecast Center, Beijing, China.
Polar Research Institute of China, Shanghai, China.

DOI: 10.4236/acs.2012.22017                

Abstract

In this study, the trends in latent and sensible heat fluxes (LHF and SHF) over the Southern Ocean (oceans south of 35?S) and the contributions of the Antarctic Oscillation (AAO), the Pacific-South America teleconnection patterns (PSA1 and PSA2) and The El Ni?o-Southern Oscillation (ENSO) to these heat fluxes were investigated using the Objectively Analyzed Air-Sea Fluxes (OAFlux) dataset from 1979 to 2008. Significant positive annual trends in LHF occur over the Agulhas Current, the Brazil Current, the oceans in the vicinity of New Zealand and southern Australia, and the eastern Pacific Ocean near between 35?S and 40?S. Significant negative seasonal trends occur in LHF which differ among the four seasons. The spatial pattern and seasonal variation of the trends in SHF over the Southern Ocean are similar to those of LHF. The spatial patterns of the trends in LHF and SHF caused by the AAO, PSA1, PSA2 and Southern Oscillation Index (SOI) indices show a wave-like feature, varying with different seasons, that can be explained by the anomalous meridional wind associated with the four indices. The above four indices account for a small portion of the trend in LHF and SHF. The residual trends in LHF over the Southern Ocean may be explained by a climate shift in the late 1990s for the four seasons. But the residual trends in SHF over the Southern Ocean are not associated with the climate shift.

Keywords

Southern Ocean; Antarctic Oscillation; Pacific-South America Teleconnection; El Niño-Southern Oscillation; Heat Flux

Conflicts of Interest

The authors declare no conflicts of interest.

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