Geophysical Research Letters · 1999 · 344 citations · 15 references
Natural SciencesEarth SciencesOceanographyAtmospheric ScienceClimatologyPhysical OceanographyMonsoon ClimatologyMonsoon SystemsOcean-atmosphere CouplingSea Surface TemperatureSea Surface Temperature VariabilityTropical ConvectionConvectionCoolingIndian MonsoonMoist Air PropertiesSea Surface Temperature FeedbacksSouth Asian MonsoonSurface Wind ObservationSurface Wind Stress
The southeastern tropical Indian Ocean experienced unusually cold sea surface temperatures and strong northwestward alongshore winds in 1994. Using multi‑source data sets and ocean model simulations, the study identified entrainment cooling near the coast and evaporative cooling away from the coast as the key processes driving the SETIO cooling. Entrainment cooling produced most of the negative SST anomaly near the coast, while evaporative cooling dominated away from the coast; suppressed convection over SETIO and moist‑air divergence enhanced local evaporation, leading to anomalous moisture transports that explain increased convection over the central equatorial Indian Ocean, India, and East Asia, and the positive feedback between enhanced and suppressed convection helped maintain the surface wind anomalies, evidencing an ocean‑atmosphere coupled phenomenon in 1994.
The southeastern tropical Indian Ocean (SETIO) was characterized by unusually cold sea surface temperature (SST) and strong northwestward alongshore surface winds during 1994. Using multi‐source data sets including ocean model simulation, two key processes are identified for the SETIO cooling. Entrainment cooling produced most of the negative SST anomaly near the coast whereas evaporative cooling dominated the process away from the coast. Convection was anomalously suppressed over SETIO and the divergence of moist air from the region helped the local evaporative process. This also led to anomalous moisture transports that explain the enhanced convection over the central equatorial Indian Ocean, India and East Asia. The positive feedback between the enhanced and suppressed convection regions in turn helped maintain the surface wind anomalies. These evidences clearly indicate the existence of an ocean‐atmosphere coupled phenomenon in the Indian Ocean during 1994.
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The NCEP/NCAR 40-Year Reanalysis Project
Eugenia Kalnay, Masao Kanamitsu, Robert Kistler et al. · Bulletin of the American Meteorological Society · 1996 · 29.1K citations