Analysis Of Rain Top Height And Cloud Top Height In Asia Based On Measurements By Trmm Precipitation Radar And Cloudsat Cloud Profile Radar

The horizontal and vertical distribution of Cloud Top Height(CTH) on seasonal scale and the quantitative relationship between CTH and rain rate in ocean of Asia are investigated based on rain rate and radar reflectivity measured by CloudSat Cloud Profiling Radar(CPR) in the Asia from June 2006 to May 2009. Results indicate that a significantly consistent distribution at 1.5 degree horizontal resolution between CTH and rain rate on seasonal scale due to the Western Pacific Subtropical High and Asia monsoon. As found in previous studies, the probability density distribution of the CTH in ocean displays two main peaks: 3.5 lower troposphere and upper troposphere between 12 and 16 km. In each season, Cloud Top Height in ocean has a similar vertical distribution of high clouds mainly in summer and higher proportion of low clouds in winter, and spring and autumn are in between them, however, more dispersed distribution of vertical structure in land Furthermore, In addition, precipitation Cloud Top altitude is higher than non-precipitation about 1-2km. According to the horizontal and vertical distribution of Cloud Top Height, clouds are classified into two categories, namely, the low clouds(CTH<10km)and high clouds (CTH>10km), and no matter what type of Cloud Top Height increases exponentially with surface rainfall rate, which are fit the form R=AHb, the results show that the height of clouds increases rapid as rain intensity increases especially for clouds deeper than 10 km.The high-frequency of CPR is also highly sensitive to the presence of both solid and liquid precipitation, that is to say CloudSat bridges a critical gap between the precipitation measurement of TRMM at low latitudes and the more global precipitation measuring goals of GPM. Therefore, radar echo characteristics, precipitation, Rain Top Height (RTH) and Cloud Top Height observed by PR and CPR are compared in Asia from August 2006 to February 2009 using 2D-CLOUDSAT-TRMM combined data provided by CloudSat official website. It is showed that PR has absolute advantage on the convective heavy of precipitation, otherwise almost the same stratiform-type precipitation samples detected by two radars because of CPR is most applicable to weak precipitation, even the rain intensity of CPR is higher than PR value besides rain rate greater than 8 mm/h. For two kinds of precipitation, the height of cloud from CPR is greater than Rain Top Height retrieved from PR, and both of them are exponentially increased with surface rain rate, and with the increase of rainfall rate, the difference between the two heights become smaller and smaller, but in terms of convective type clouds, the echo top height obtained from PR and CPR are more closer.