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.
Highlights
The Southern Ocean plays a critical role in the variability of weather and climate at southern high latitudes through heat and moisture transfer between the upper ocean and atmospheric boundary layer [1,2]
The spatial patterns of the trends in LHF and SHF caused by the Antarctic Oscillation (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
Positive trends occur in the spatial patterns of LHF over the Southern Ocean that are consistent among the seasons, while a large difference occurs in the negative trends in LHF
Summary
The Southern Ocean (oceans south of 35 ̊S) plays a critical role in the variability of weather and climate at southern high latitudes through heat and moisture transfer between the upper ocean and atmospheric boundary layer [1,2]. Yang et al (2006) detected a positive trend of Southern Ocean surface wind stress from 1980 through 1999 and its close linkage with spring Antarctic ozone depletion [14]. Whether LHF and SHF over the Southern Ocean have changed, and if so, which meteorological variables and largescale circulation indices influence them need to be explored. This paper investigates the extent to which AAO, the Pacific-South America teleconnection patterns (PSA1 and PSA2), and ENSO, as well as surface meteorological variables, can account for the recent trends in LHF and SHF over the Southern Ocean.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
