The DYNAMO/CINDY Atmospheric Sounding Array: Its Performance and Plans for Quality Control

During DYNAMO/CINDY, a network of sounding stations was established over the equatorial central Indian Ocean to collect observations that were necessary to test hypotheses on key aspects of MJO initiation. The primary scientific objective of this network was to provide sounding-based estimates of the vertical profiles of divergence and diabatic heating in the atmosphere before, during, and after the initiation or passage of an MJO over the central Indian Ocean. The measurements were intended to complement independent observations of the evolving cloud fields from land and ship-borne radars and satellites. The sounding data will also be used to construct large-scale forcing fields for initializing CRM and SCM simulations to help in development of improved model parameterizations.

The core of the enhanced sounding network consisted of 6 sites (two ships and four land stations) forming two adjacent quadrilateral arrays: one centered near 3N and the second near 4S. During roughly the first half of the experiment, sites in the southern enhanced sonde array had 8 launches per day which were designed to sample the diurnal cycle to understand its role in the evolution of the MJO. In addition to the enhanced network, a number of operational sonde sites in the large-scale domain (in the tropics from Eastern Africa to the West Pacific) were designated as priority sounding sites (PSS). Data from these sites were collected and will be used to construct an enhanced analysis of the large-scale structure of the MJO as it propagates through the Eastern Hemisphere.

During the experiment, our CSU team monitored GTS-resolution sounding data from the PSS and enhanced sonde network, performed some limited quality control, and produced a variety of real-time analyses. This presentation will review the performance of the sonde network and the quality control procedure to be used in processing the high-resolution sounding data.