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Publication:
Yongjing Zhao, Yongfu Qian
"Analyses of the Impacts of Global SSTA on Precipitation Anomaly in China."
Jurnal of Tropical Meteorology (accepted)

Abstract: The spatial and temporal coupling relations between the monthly global SST anomaly field offered by Climatic Research Unit from 1951 to 2005 and the average monthly precipitation anomaly offered by 160 stations in China are analyzed. The spatial and temporal characteristics are analyzed by EOF and SVD methods. After that, the influences of the spatial distribution and temporal evolution of global SST anomaly field on China’s precipitation anomaly are analyzed, and analyzing the key area becomes the emphasis, which influences the precipitation anomaly in our country in particular period of time. The results show that there are three key regions which have important influence on the precipitation of China ,that is, North Pacific; Indian Ocean—South China Sea and Middle and East Equatorial Pacific. The SST anomaly fields of the three key regions have both interannual and interdecadal variations, and the situation changed suddenly in the late 1970s. Among those areas, there are three most important influences for the precipitation in China, which for July is North Pacific temperature in early winter, for May is temperature of the Indian Ocean and South China Sea in winter and spring, and for July is the temperature of the Middle and East Equatorial Pacific in winter. At last, the coupling relations between the previous SST anomaly field of each key region and the precipitation field in different periods and different regions of China are analyzed. This relation may help reducing the uncertainty in prediction of the abnormality of regional rainfall in China.
Keywords: Anomaly of global sea temperature; Anomaly of China’s precipitation; EOF and SVD method; Climate change

Yongjing Zhao, Yongfu Qian
"Analyses of the Impacts of Global SSTA on Temperature Anomaly in China"
Jurnal of Nanjing University (accepted)

Abstract: The spatial and temporal coupling relations between the monthly global SST anomaly field offered by Climatic Research Unit in 1951 to 2005 and the average monthly temperature anomaly offered by 160 stations of China are analyzed by SVD method. Also, the spatial and temporal characteristics are analyzed by EOF method. After that, the influences of the spatial distribution and temporal evolution of global SST anomaly field on China’s temperature anomaly are analyzed. The results show that there are five key regions which have important influence on the temperature of China ,that is, Northeast Pacific; East China Sea—South China Sea; North India; Middle and East Equatorial Pacific and the Tropical Atlantic. The SST anomaly fields of the five key regions have both inter-annual and inter-decadal variations, and the situation changed suddenly in the late 1970s.At last, the coupling relations between the previous SST anomaly field of each key region and the temperature field in different periods and different regions of China are analyzed. This relation may help reducing the uncertainty in prediction of the abnormality of regional temperature in China.
Keywords: Anomaly of global sea surface temperature (SSTA); Temperature Anomalies in China; EOF and SVD method; Climate change

Yongjing Zhao, Yongfu Qian
"The Interaction Between Global SSTA and Temperature Anomaly in China over 50 years"
2008 Chinese Meteorological Society (full paper in submission)

Chenxi Wang, Fan Yu, Yongjing Zhao
"MTSAT Multi-Spectral Satellite-Based observation of real-time Precipitation in East China at Plum rain season"
2008 International Society for Optical Engineering (full paper in submission)

Abstract:
The retrieval of MTSAT multi-spectral satellite image rainfall intensity field was studied, with which the “unit-feature spatial classification method” was proposed to become the foremost basis of the possibility of continuous observation of real-time precipitation from geostationary satellite. In this method, MTSAT multi-spectral satellite measured value and measured precipitation rate from high density ground stations of plum rain season in east china (Jiangsu, Zhejiang and Anhui) in 2007 are combined to conduct the cooperative analysis, and therefore the distribution features of the level of each precipitation probability and each precipitation intensity are well established on different two-dimensional and three-dimensional spectral feature spaces. On the basis, the discrimination matrices, correspondingly, are established for precipitation probability and precipitation intensity of different spectral combinations. Different spectral combinations are used for the construction of the discrimination matrices of the day and the night, respectively. For the day, IR1(), IR3(), VIS(), IR12()and IR13()are available, among which IR1, VIS and IR3(or IR13)are mainly used ; for the night, IR1, IR3, IR4(), IR12, IR13, IR14()and IR24()are available and IR1, IR3 and IR24(or IR14)are mainly used. The contrast test between the observed data of precipitation and the retrieval results based on precipitation data from basic stations and reference stations in China in 2007 shows that, 30% precipitation probability can ideally distinguish precipitation area from non-precipitation area; and the analysis of precipitation intensity category also matches well with the fact. It is well known that the observation of satellite is instantaneous one time per hour while the rain gauge observation is an accumulative process during an hour. The error study further suggests that the difference between the two observation methods is the vital cause of the relative error.

Keywords: UFSC, MTSAT, satellite estimated rainfall, calibration matrices