| dc.description.abstract | Both clouds and precipitation play an important role in the hydrological cycle. Among the ten major cloud species, Cumulonimbus (Cb) might have strong relationship between its internal structure and precipitation. In the development of Cbs, it is typically associated with the formation of severe precipitation. Therefore, it leads several natural disasters like flash flooding and lightening with intense rainfall in a short duration. From previous study, both the vertical structure and microphysical properties of cloud present different characteristics in the various types of precipitation. This study will focus on the use of satellite observation data to understand the relationship between the structure of deep convective core (DCC) and the microphysical properties of cloud and precipitation.
We analyzed 24 months global collocated CloudSat/ CPR, JAXA GSMaP precipitation data to identify three frequent DCC regions. The results show the developing height of DCC has positive correlation with the rain rate. The vertical distribution of the ice number concentration (INC), ice effective radius (IRe), relative humidity (RH) along with vertical updraft velocity in the troposphere reveal the larger values that are associated the heavier rain rate, which suggests these are important and sensitive factors to the severe rain rate.
In the mid-level of troposphere (5-10 km in altitudes), the representative cloud parameter is the IRe. The particles size of heavy precipitation is larger than non-precipitation. The biggest difference between the rain rate and IRe is the most significant in the altitudes between 7 and 9 km. At the same time, the change in RH affects the particle size and rain rate as well. At this height, the percentage of IRe > 120 μm is greater than 50 ％, and there is a higher probability of heavy rain rate occurrence; in the upper level is the INC. The height of 13-14 km is the key to discuss the INC and rain rate. When the INC > 450 L-1 is prone to heavy rain rate, while INC ＜ 400 L-1 is prone to weak precipitation or non-precipitation. As a result, the vertical velocity, RH, convective height, IRe, INC and precipitation are known to be closely related to this study.
After further analysis of the data from the three DCC developing regions in the world, it was found that the environmental characteristics of DCC have regional environmental characteristics. Among them, SEA is affected by the shape of the sea and the land, water vapor is abundant, and the updraft is strong, therefore, the environmental characteristics of DCC will be stronger than the other two regions. SEA has a large IRe distribution ratio of AF and AZ in 5-8 km. In the upper troposphere, the INC begins to change with rain rate which is 12 km in SEA, and 11 km in AF and AZ.
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