Differences in Cloud Vertical Structures between the Tibetan Plateau and Eastern China Plains during Rainy Season as Measured by CloudSatCALIPSO

Abstract EN

Cloud vertical structures over the Tibetan Plateau (TP) and Eastern China Plains (ECP) were analyzed by using data in rainy seasons from 2006 to 2009, in order to clarify the cloud development over adjacent regions but with distinct topographies.

Results indicate that the largest occurrences of cloud top height over the TP are at 7-8 km above mean sea level, which is about 4 km lower than that over the ECP.

Mixed-phase clouds dominated more than 30% over the TP, while it is lower than 10% over the ECP.

The infrequent mixed-phase clouds over the ECP are attributed to the unique dynamic and moisture situations over the downstream areas of the TP.

Ice clouds have similar occurrences over the two regions.

The prominent distinctions are manifested by the probability density of cloud thickness.

The probability density of cloud thickness around 4–8 km is about 2% higher over the TP than the ECP.

However, there is almost no ice cloud thicker than 10 km over the TP, while it is about 1% over the ECP.

Compared with those over the ECP, every cloud layer within multilayered clouds is generally higher and thinner over the TP, which is closely related to the elevated surface and the resulting thinner troposphere.

The significant differences in cloud vertical structures between the TP and the ECP present in this study emphasize that topographical characteristics and the resulting moisture and circulation conditions have strong impacts on the cloud vertical structures.