| dc.description.abstract | Intense convections often occur over the Taiwan area during the afternoons of summer. The relevant mechanisms behind this weather phenomenon is one of the various issues that strongly attracts the attention of meteorologists and forecasters. As the afternoon convection development is very rapid, data observed by traditional methods alone can not produce an early warning, which often results in serious damages to the environment and livelihood of people. Due to the lack of traditional radiosonde observational data near the waters of the Taiwan area, it further emphasizes the importance of the applications in satellite monitoring. The major purpose of this research is to establish a method for the polar-orbiting NOAA-15 satellite in retreiving temperature and dew point profiles over the Taiwan area, then we apply this result in convention environment during the afternoon in summer.
The results of retrieval using temperature and dew point profiles show that the root mean square errors and correlation coefficients of temperature (the dew point) are 2.47 (4.13) 、2.18 (3.13) 、1.76 (5.07) 、1.97 (5.73) 、2.05 (3.73) and 0.83、0.82、0.71、0.76、0.67. About temperature, the r.m.s. error in each layer is nearly 2.0 degrees when the cloud coverage is less than 50% and the standard deviation is about 0.5 degree. Besides, about dew point, the r.m.s. error in each layer is nearly 4.3 degrees when the cloud coverage is less than 50% and the standard deviation is about 0.9 degree.
In this study, we utilize the NOAA satellite data to estimate the atmospheric stability around Taiwan area and moisture at 500 hPa and also apply the results to real cases. It shows that the same importance of both atmospheric moisture content and stability in convention system during the afternoon in summer. Additionally, by using the samples form 2003 June to September (441 cases), we predict the threshold of convective precipitation from atmospheric stability and moisture data and apply to the 470 cases of 2002 also shows good agreements. In elementary analysis, we can get accuracy about 85 % of quantification prediction in precipitation. It shows that the results can improve the prediction of convention system during the afternoon in summer. | en_US |