Matthew R. Smith

Interannual Variability of the Tropical Radiation Balance and the Role of Extended Cloud Systems

Abstract The tropical radiation balance is investigated on an interannual time scale using a five-year(1979–83) dataset obtained from the Nimbus-7 Earth Radiation Budget (ERB) experiment. The study emphasizes the separate contributions to interannual fluctuations in the global radiation balance by the tropics and extratropics. An attempt is made to Identify source regions within the tropics that give rise to the fluctuations and to quantify the effect of the fluctuations on zonal heat transport. Superimposed on the five-year global trend pattern of net radiation are large amplitude nonseasonal variations largely confined to tropical latitudes. The significant regions are the Southwest–East Asian (SW–EA) monsoon and two regions associated with the ascent and descent branches of the Pacific Walker Cell. A “cloud reciprocity index” is formulated in order to examine the degree to which extended cloud systems over the oceanic tropics can induce these interannual fluctuations in the radiation balance. The SW–EA...

Critical Analyses of Data Differences between FNMOC and AFGWC Spawned SSM/I Datasets

Antenna temperatures and the corresponding geolocation data from the five sources of the Special Sensor Microwave/Imager data from the Defense Meteorological Satellite Program F11 satellite have been characterized. Data from the Fleet Numerical Meteorology and Oceanography Center (FNMOC) have been compared with data from other sources to define and document the differences resulting from different processing systems. While all sources used similar methods to calculate antenna temperatures, different calibration averaging techniques and other processing methods yielded temperature differences. Analyses of the geolocation data identified perturbations in the FNMOC and National Environmental Satellite, Data and Information Service data. The effects of the temperature differences were examined by generating rain rates using the Goddard Scattering Algorithm. Differences in the geophysical precipitation products are directly attributable to antenna temperature differences.

A PC-based interactive imaging system designed for Insat data analysis and monsoon studies

A PC-based interactive image processing system has been developed for aiding the analysis of Indian Geosynchronous Satellite (INSAT) data for Asian monsoon studies. In view of its diminutive stature, the system has been given the name “MIDGET,” for a Micro-based Image Display and Graphics Enhancement Tool. Various analysis procedures involving INSAT data and other monsoon datasets are described in conjunction with the MIDGET system. These include the use of the system for monitoring monsoon evolution and the behavior of organized tropical storms, analysis of low-frequency intraseasonal oscillations, diagnostic studies of cloudiness, retrieval of monsoon precipitation and its relationship to satellite cloudiness, and statistical prediction of monsoon cloud bands associated with low-frequency intraseasonal fluctuations of monsoon rainfall. The system is designed as a workstation terminal in a supercomputer environment. The basic virtue of this system is that it is an inexpensive approach for generating a hi...