SST Data Fusion Of China Satellites Based On LAPS And Its Application In Cold Wave In East Offshore Of China

Satellite sea surface temperature(SST) can provide large area and high resolution SST data. Providing information of mulit-source measured data for the establishment of regional SST reanalysis data. Especially for China offshore, the coastline is complicated, islands are scattered, lack for the regional ocean reanalysis data. China FY and HY-2 satellite data can provide precise description, which is very precious for China Yellow Sea and East Sea. But by the limitations of sensor working principle, satellite monitoring is sensitive to the topography, sea land boundary, cloud and electromagnetic field etc, may produce random missing area. Therefore we choose American LAPS(Local Analysis Prediction System) to fuse FY and HY-2 satellite data. The system can ensure the coordination of spatial and temporal characteristics of different elements. Generating reanalysis data with standard format.Because of the LAPS system has no special input channel for satellite SST data, the different sensing principles of FY and HY-2 satellites, and the characteristics of random variation of satellite data inspatiotemporal. Raw data of satellites is preprocessed by several steps, including outliers discrimination and elimination, the anomaly gradient discrimination and elimination, the numerical treatment of different satellite scanning grids, and data smoothing etc. Results show that process of satellite data preprocessing are effective and necessary.Preprocessed HY-2 and FY-2E satellites data are fused through the LAPS system. The results show that FY-2E SST can make up the missing data of HY-2 in the offshore.The fusion of backgroung and HY-2 and FY-2E SST keep more short-wave information. Comparison of the fusion SST and field measured SST show that effect of background and HY-2 is the best. Comparison of the fusion SST and OISST show the effect of background and FY-2E is better.The HY-2 and FY-3C fusion SST data are applicated on the process of cold wave and strong cold air. The results show that the two kinds of fusion data can express the temperature change, which the background can not reflect. The fusion data also make up the missing area of satellite data. Further, using the fusion data in diagnostic analysis, the expansion of cold air from land to sea is clearly seen. The sea surface temperature is higher than near sea surface air temperatue and the cooling rate of sea surface temperature is less than near sea surface air temperatue. Comparing the air-sea heat flux of satellite fusion data with the FNL data, fusion data can show more fine thermal center.Preprocessed FY and HY-2 satellites SST data is fused into a reanalysis data of China eastern seas by the LAPS system. Through statistical tests, the SST products can provide the detail description of spatiotemporal features of SST distribution. Furthermore the diagnostic analysis can be done by the reanalysis data for the mesoscale air-sea synoptic process.The results can provide information and reference for the air-sea heat flux analysis of China offshore regions.