Study On The Characteristics Of Sea Surface Temperature Anomalies In The Southern India Ocean

By selecting the data of tropical cyclones in South India ocean in 1980-2014 years 12-4 months,the global sea surface temperature (SST) and NCEP/NCAR reanalysis monthly average data,, through using the latest development of statistical dynamic diagnostic analysis method - generalized equilibrium feedback analysis(GEFA),diagnosis the sea surface temperature anomaly (SSTA) model for the climatic variability of tropical cyclone (TC) in southern India ocean,and studied the forcing effect and its influence of SSTA mode on the frequency of TC formation in southern India ocean; Through the comparative analysis of South India ocean TC formation frequency of the relevant SSTA modes of multiple linear regression, EFA and GEFA feedback response,discussing the linear interaction of the SSTA modes and the modulation of the frequency variability of the TC formation in the southern India ocean.The main conclusions are as follows:(1) The results of GEFA diagnosis showed that the frequency of TC generation in southern India has a significant response to NP1 andTA2, and the corresponding response amplitudes were 0.67 and 0.49TC, respectively. When NP1 appears to be similar to the positive phase of the Pacific Decadal Oscillation (PDO), the 850hPa relative vorticity has a significant positive abnormal response from west to East in the India Ocean near 15°S,and the vertical wind shear is a significant negative abnormal response in most of the east of Madagascar, the relative humidity of 600hPa in the eastern part of Madagascar is a positive abnormal response; When the time coefficient of TA2 is positive, 850hPa relative vorticity and 600hPa relative humidity in Australia northwest of India ocean showed remarkable positive response,vertical wind shear in Australia northwest of India ocean as a significant negative response.(2) South India ocean TC anomalous frequency over many years and multi age,850hPa relative vorticity and 600hPa relative humidity in the waters east of Madagascar are positive response value, 200hPa-850hPa vertical wind shear in the South India ocean is negative response value, provides a favorable environment for TC formation in southern India ocean.(3) Comparison of GEFA and EFA shows that the effect of NP2 and SA2 on the TC formation in the southern India ocean is greatly influenced by other basins;Compared with GEFA and multiple regression, it was found that the TIO1 atmosphere had a strong change in the atmosphere, and the effect of SSTA on the atmosphere in the region was weaker than that of the atmosphere to SST.