WATER VAPOUR WEIGHTED MEAN TEMPERATURE MODEL FOR GPS-DERIVED INTEGRATED WATER VAPOUR IN PENINSULAR MALAYSIA

Abstract

This paper presents the development of TM model by using the radiosonde stations from Peninsular Malaysia. Two types of TM model were developed; site-specific and regional models. The result revealed that the estimation from site-specific model has small improvement compared to the regional model, indicating that the regional model is adequately to use in estimation of GPS-derived IWV over Peninsular Malaysia. Meanwhile, this study found that the diurnal cycle of TS has influenced the TM–TS relationship. The separation between daytime and nighttime observation can improve the relationship of TM–TS. However, the impact of diurnal cycle to IWV estimation is less than 1 %. The TM model from Global and Tropic also been evaluated. The Tropic TM model is superior to be utilized as compared to the Global TM model.