Mesoscale Updraft Magnitude and Cloud-Ice Content Deduced from the Ice Budget of the Stratiform Region of a Tropical Cloud Cluster

Abstract

Radar observations obtained during Winter MONEX describe the three-dimensional structure and development of the mesoscale stratiform region of a tropical cloud cluster. The magnitudes of the mesoscale updraft and cloud-ice mass content within an upper tropospheric stratiform cloud deck are deduced from a formulation of the ice budget of the stratiform region. Measurements of radar reflectivity at upper levels serve as the primary input data. Aircraft observations of ice particles are also used to guide the calculations. The mesoscale updraft magnitude and cloud-ice mass content are determined hourly over a period of 12 h. The updraft velocities were 10-23 cm s⁻¹, and the cloud-ice contents were 0.1-0.3 g m⁻³. The vertical velocity estimates agree well with estimates obtained for the same cloud cluster by Johnson (1982) using the kinematic method.