Annual, seasonal, and interannual variability of air-sea heat fluxes in the Indian Ocean
MetadataShow full item record
This study investigated the accuracy and physical representation of air–sea surface heat flux estimates for the Indian Ocean on annual, seasonal, and interannual time scales. Six heat flux products were analyzed, including the newly developed latent and sensible heat fluxes from the Objectively Analyzed Air–Sea Heat Fluxes (OAFlux) project and net shortwave and longwave radiation results from the International Satellite Cloud Climatology Project (ISCCP), the heat flux analysis from the Southampton Oceanography Centre (SOC), the National Centers for Environmental Prediction reanalysis 1 (NCEP1) and reanalysis-2 (NCEP2) datasets, and the European Centre for Medium-Range Weather Forecasts operational (ECMWF-OP) and 40-yr Re-Analysis (ERA-40) products. This paper presents the analysis of the six products in depicting the mean, the seasonal cycle, and the interannual variability of the net heat flux into the ocean. Two time series of in situ flux measurements, one taken from a 1-yr Arabian Sea Experiment field program and the other from a 1-month Joint Air–Sea Monsoon Interaction Experiment (JASMINE) field program in the Bay of Bengal were used to evaluate the statistical properties of the flux products over the measurement periods. The consistency between the six products on seasonal and interannual time scales was investigated using a standard deviation analysis and a physically based correlation analysis. The study has three findings. First of all, large differences exist in the mean value of the six heat flux products. Part of the differences may be attributable to the bias in the numerical weather prediction (NWP) models that underestimates the net heat flux into the Indian Ocean. Along the JASMINE ship tracks, the four NWP modeled mean fluxes all have a sign opposite to the observations, with NCEP1 being underestimated by 53 W m−2 (the least biased) and ECMWF-OP by 108 W m−2 (the most biased). At the Arabian Sea buoy site, the NWP mean fluxes also have an underestimation bias, with the smallest bias of 26 W m−2 (ERA-40) and the largest bias of 69 W m−2 (NCEP1). On the other hand, the OAFlux+ISCCP has the best comparison at both measurement sites. Second, the bias effect changes with the time scale. Despite the fact that the mean is biased significantly, there is no major bias in the seasonal cycle of all the products except for ECMWF-OP. The latter does not have a fixed mean due to the frequent updates of the model platform. Finally, among the four products (OAFlux+ISCCP, ERA-40, NCEP1, and NCEP2) that can be used for studying interannual variability, OAFlux+ISCCP and ERA-40 Qnet have good consistency as judged from both statistical and physical measures. NCEP1 shows broad agreement with the two products, with varying details. By comparison, NCEP2 is the least representative of the Qnet variabilities over the basin scale.
Author Posting. © American Meteorological Society, 2007. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 20 (2007): 3190-3209, doi:10.1175/JCLI4163.1.
Suggested CitationArticle: Yu, Lisan, Jin, Xiangze, Weller, Robert A., "Annual, seasonal, and interannual variability of air-sea heat fluxes in the Indian Ocean", Journal of Climate 20 (2007): 3190-3209, DOI:10.1175/JCLI4163.1, https://hdl.handle.net/1912/4118
Showing items related by title, author, creator and subject.
Mechanisms governing interannual variability of upper-ocean temperature in a global ocean hindcast simulation Doney, Scott C.; Yeager, Stephen G.; Danabasoglu, Gokhan; Large, William G.; McWilliams, James C. (American Meteorological Society, 2007-07)The interannual variability in upper-ocean (0–400 m) temperature and governing mechanisms for the period 1968–97 are quantified from a global ocean hindcast simulation driven by atmospheric reanalysis and satellite data ...
Interannual variability of winter-spring temperature in the Middle Atlantic Bight : relative contributions of atmospheric and oceanic processes Chen, Ke; Kwon, Young-Oh; Gawarkiewicz, Glen G. (John Wiley & Sons, 2016-06-18)Relative contributions between the local atmospheric and oceanic processes on the interannual variability of winter-spring shelf temperature in the Middle Atlantic Bight (MAB) are investigated based on a regional ocean ...
Contribution of ocean, fossil fuel, land biosphere, and biomass burning carbon fluxes to seasonal and interannual variability in atmospheric CO2 Nevison, Cynthia D.; Mahowald, Natalie M.; Doney, Scott C.; Lima, Ivan D.; van der Werf, Guido R.; Randerson, James T.; Baker, David F.; Kasibhatla, Prasad S.; McKinley, Galen A. (American Geophysical Union, 2008-02-12)Seasonal and interannual variability in atmospheric carbon dioxide (CO2) concentrations was simulated using fluxes from fossil fuel, ocean and terrestrial biogeochemical models, and a tracer transport model with time-varying ...