基于Himawari-8卫星资料对三个南海强台风水汽亮温和红外亮温的对比分析OA

At present,most studies on typhoons focus on the relationship between a single brightness temperature and precipitation,while the combined use of infrared and water vapor brightness temperatures is relatively rare.This study examines the variation characteristics of infrared and water vapor brightness temperatures during the life cycle of typhoons,including"Mujigae"(201523),"Hato"(201713)and"Mangkhut"(201822)using Himawari-8 satellite data.The analysis focuses on Band 9(infrared)and Band 14(water vapor),comparing these measurements to understand their relationship with the typhoon's precipitation rate.Key Findings:(1)In the early stages of Typhoon"Hato"and Typhoon"Mangkhut",when both were tropical storm,there was a period of time during which the difference between brightness temperatures at the typhoon's periphery and within the typhoon's core was small.During the time when"Mangkhut"was a severe typhoon or a super typhoon,the brightness temperatures from 30 km away from the typhoon center to the area of the typhoon center were apparently higher than other area of the typhoon.(2)When the typhoon structure is mature,at the typhoon's periphery and the eye of the typhoon,water vapor brightness temperatures are typically lower than infrared temperatures.In contrast,within the typhoon's core,these temperatures are more similar.(3)When the typhoon is over the sea,a significant difference in brightness temperature is observed between the core and the periphery.This difference diminishes as the typhoon approaches landfall.(4)For Typhoon"Mujigae"and Typhoon"Hato",convective precipitation occurred after the typhoon made landfall,but for Typhoon"Mangkhut",convective precipitation mainly occurred when the typhoon was over the sea,while almost no convective precipitation occurred when the typhoon made landfall.(5)Throughout the typhoon's lifecycle,areas with significant precipitation or heavy rainfall correspond to regions where the D-value(the difference between infrared and water vapor brightness temperatures)is less than 10 K,or even close to 0 K.This indicates a strong correlation between the D-value and precipitation intensity.