摘 要: | The monthly mean sea surface temperature data of 6 areas are used to study the El Nino/Southern Oscillation signals in the global tropical ocean. These areas are in the 5°N-5°S latitude zone at 1) eastern Pacific (110°-140°W), 2) western Atlantic (30°-50°W), 3) eastern Atlantic (10°W-10°E), 4) western Indian Ocean (30°-50°E), 5) central Indian Ocean (70°-90°E) and 6) far western Pacific (120°-140°E), and the data cover the 120-month period of December 1968 to November 1978.A power spectrum analysis shows that the characteristic time of the El Nino/Southern Oscillation (about 3-4 years) appears not only in the eastern Pacific but also in other areas of the tropics except for the western Pacific, where the spectrum is of white noise. The amplitude of oscillation in the eastern Pacific is about 4 times larger than the others, making the El Nino/Southern Oscillation signal the strongest in this area. According to a cross-spectrum analysis, there is no time lag between the variation in the cent
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