Doppler Radar Observations on the Structure and Characteristics of Tropical Clouds during the TOGA-COARE IOP in Manus, Papua New Guinea

Abstract

Observations of tropical convection and cloud clusters with two X-band Doppler radars were carried out on Manus Island, Papua New Guinea for two and a half months from 12 November 1992 during the Intensive Observation Period (TOP) of the TOGA-COARE. Several different types of clouds were observed by Doppler radars during the period, such as squall lines, convective clouds and stratiform clouds associated with cloud clusters, isolated convective clouds over the island in the day time, etc. Outlines of the observations on Manus Island and brief reviews of the results of these observations are described. Preliminary summaries of the analyses on the observations are: 1) A warm rain process dominates at the beginning stage of radar echo development and the maximum radar reflectivity is recognized at this stage, 2) The maximum echo top height is observed within 3 hours from the first echo, 3) The maximum echo area within the radar range was analyzed a few to several hours later than the time of maximum echo top height corresponding to the size of cloud cluster, 4) In the long-lasting stratiform echo, updrafts independent from those below the melting layer were identified above the melting layer. It is concluded that further studies utilizing these observational data may reveal the structure and the evolution mechanism of tropical cloud clusters.

Doppler Radar Observation of the Structure and Characteristics of Tropical Clouds during the TOGA-COARE IOP in Manus, Papua New Guinea

“…Omega sondes were launched four times a day at Momote (about 20km east of the radar site; see Fig. 1 and Uyeda et al, 1995) during the observation pe- nod. However, dew point data were not available in some sounding data on December 16 (second and third cases).…”

“…The major purposes of the Doppler radar observation were to clarify the kinematic structure of tropical convective clouds which consist of cloud clusters and to determine the three-dimensional distribution of precipitation. An overview of the dual Doppler radar observation on Manus Island is shown by Uyeda et al (1995).…”

Dual Doppler Radar Observation of a Tropical Rainband Developed from Two Convective Clouds

“…The observational systems of the TOP of TOGA-COARE and the characteristics of the radars have been described in detail by Uyeda et al (1995). Data from the radar system were collected by performing full 360 plan position indicator (PPI) volume scans.…”

Doppler Radar Observations on the Structure and Characteristics of Tropical Clouds during TOGA-COARE IOP in Manus, Papua New Guinea

“…They were installed on Manus Island, Papua New Guinea, which is at the western edge of the outer sounding array of TOGA-COARE. The locations of these radars as well as the information about these radars are described in Uyeda et al (1995). Three-dimensional data of reflectivity and Doppler velocity were obtained from synchronized vol- The circles indicate the range of ILTS radar on Manus Island.…”