Tropical Warm Pool Surface Heat Budgets and Temperature Contrasts between 1997/98 El Niño and 1998/99 La Niña

• Published in: Journal of climate Vol. 17; no. 9; pp. 1845 - 1858
• Main Authors: Chou, Shu-Hsien, Chou, Ming-Dah, Chan, Pui-King, Lin, Po-Hsiung, Wang, Kung-Hwa
• Format: Journal Article
• Language: English
• Published: Boston, MA American Meteorological Society 01.05.2004
• Subjects: Climate; Climatology. Bioclimatology. Climate change; Comparative studies; Cooling; Datasets; Earth, ocean, space; El Nino; Equatorial regions; Evaporative cooling; Exact sciences and technology; External geophysics; Heat; Heat budget; Heating; La Nina; Meteorology; Ocean currents; Oceans; Sea surface temperature; Seas; Solar heating; Temperature; Tropical regions; Wind velocity; Equatorial Pacific; Indian Ocean; Pacific Ocean; Climatology; Indian Ocean; heat balance; Ocean dynamics; Sea surface temperature; ocean-atmosphere interaction; Interannual variation; La Niña; GMS satellite; El Nino; winds; Southern oscillation; cooling; warming; Cloudiness; Pacific Ocean; spatial variations; Microwave radiometry; heat transfer; seasonal variations; radiance
• ISSN: 0894-8755; 1520-0442
• DOI: 10.1175/1520-0442(2004)017<1845:TWPSHB>2.0.CO;2

Seasonal to interannual variations of the net surface heating (F NET) and its relationship to sea surface temperature tendency (dTs/dt) in the tropical eastern Indian and western Pacific Oceans are studied for the period October 1997–September 2000. The surface heat fluxes are derived from the Special Sensor Microwave Imager and Japanese Geostationary Meteorological Satellite radiance measurements. It is found that the magnitude of solar heating is larger than that of evaporative cooling, but the spatial variation of the latter is significantly larger than the former. As a result, the spatial patterns of the seasonal and interannual variability ofF NETare dominated by the variability of evaporative cooling. Seasonal variations ofF NETanddTs/dtare significantly correlated, except for the equatorial western Pacific. The high correlation is augmented by the high negative correlation between solar heating and evaporative cooling. The change ofF NETbetween the 1997/98 El Niño and 1998/99 La Niña is significantly larger in the tropical eastern Indian Ocean than that in the tropical western Pacific. For the former region, reduced evaporative cooling arising from weakened winds during El Niño is generally associated with enhanced solar heating due to reduced cloudiness, leading to enhanced interannual variability ofF NET. For the latter region, reduced evaporative cooling due to weakened winds is generally associated with reduced solar heating arising from increased cloudiness, and vice versa. Consequently, the interannual variability ofF NETis reduced. The correlation between interannual variations ofF NETanddTs/dtis weak in the tropical western Pacific and eastern Indian Oceans, indicating the importance of ocean dynamics in affecting the interannual SST variation.