Remote Sensing Laboratory - Applied Electromagnetic Research Institute

The Precipitation Radar (PR) onboard Tropical Rainfall Measuring Mission (TRMM) satellite can measure the three dimensional structure of rainfall global scale.

Here, rain echo statistics of the echo not reach to the Earth surface (called virga and anvil) are shown. Note that anvil type is defined echo bottom is above the melting level in this analysis and otherwise virga type. Top panel (1) shows virga/anvil type echo occurrence rate among total observations (including no-echo cases). Next panel (2) shows the virga + anvil type among total echo observation case and (3) is same (2) except for only anvil type. As a reference average monthly rainfall is shown in the bottom panel (4).

Major characteristics in (1) show the virga/anvil type occurrence is almost corresponds to the average rainfall. If the case is confined echo observation cases (2), high virga/anvil type area appears over Sahara desert, Namibian desert, Atacama Desert, Australia and offshore of California. High anvil type area appears over high mountain region (Tibetan Plateau and Andes Mountains) and offshore the Namibian desert, and Atacama Desert.