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Hinton, Barry B.

Publications and source records attributed to Hinton, Barry B..

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

Three years of rainfall over the Indian Ocean

Monthly rain falling on the Indian Ocean is mapped for the period 1979 through 1981 by means of observations of the Nimbus-7 Scanning Multichannel Microwave Radiometer. Both stationary and mobile parts were found in the pattern of rain. The stationary part consisted of three zonal and two meridional bands. Only one, the band along and south of the equator, maintained a strong presence through all seasons. A north equatorial counterpart to this south equatorial band also was persistent, but weak. The mobile part of the pattern took the form of a wave. The locus of this wave was an eastward-tilted figure eight, which straddled the equator. The wave moved clockwise along the north loop of the figure eight, counterclockwise along the south loop. The crest of the wave crossed the equator from south to north in May or June and crossed the equator from north to south between August and October. Along its path the equatorial bands were alternately amplified and damped, and the transient bands were activated and suppressed. The effect of the bands and wave was to produce a strong 'monsoon' (annual cycle, summer peak) signature in rain falling over both the northeastern and southwestern reaches of the Indian Ocean.

Martin, David W.↗
NASA NTRS1992

A passive microwave algorithm for tropical oceanic rainfall

This study discusses a rainfall algorithm utilizing six channels of microwave radiance data from the Nimbus-7 Scanning Multifrequency Microwave Radiometer. The algorithm is intended for short-term climate studies over the ocean at low latitudes. To find a set of functional relationships, rain rates are regressed on brightness temperatures for each channel. Next, these functions are integrated over a class of rain-rate distributions to find relations between mean brightness temperatures and mean rain rates. This step accounts for beam filling. Finally, weights are obtained for combining the rain rates from the individual channels. The weights vary with the rain rates, so that the optimum combination of channels is always used. Results are stored in a database grid 1 deg latitude x 1 deg longitude by one month. To test the algorithm, three years (1979-81) of data from the Indian Ocean are processed.

Hinton, Barry B.↗
NASA NTRS1991

Application of lightning data to satellite-based rainfall estimation

Information on lightning may improve rain estimates made from infrared images of a geostationary satellite. We address this proposition through a case from the Cooperative Huntsville Meteorological Experiment (COHMEX). During the afternoon and evening of 13 July 1986 waves of showers and thunderstorms developed over and near the lower Tennessee River Valley. For the shower and thunderstorm region within 200 km of the National Weather Service radar at Nashville, Tennessee, we measure cold-cloud area in a sequence of GOES infrared images covering all but the end of the shower and thunderstorm period. From observations of the NASA/Marshall direction-finding network in this small domain, we also count cloud-to-ground lightning flashes and, from scans of the Nashville radar, we calculate volume rain flux. Using a modified version of the Williams and Houze scheme, over an area within roughly 240 km of the radar (the large domain), we identify and track cold cloud systems. For these systems, over the large domain, we measure area and count flashes; over the small domain, we calculate volume rain flux. For a temperature threshold of 235K, peak cloud area over the small domain lags both peak rain flux and peak flash count by about four hours. At a threshold of 226K, the lag is about two hours. Flashes and flux are matched in phase. Over the large domain, nine storm systems occur. These range in size from 300 to 60,000 km(exp 2); in lifetime, from about 2 1/2 h to 6 h or more. Storm system area lags volume rain flux and flash count; nevertheless, it is linked with these variables. In essential respects the associations were the same when clouds were defined by a threshold of 226K. Tentatively, we conclude that flash counts complement infrared images in providing significant additional information on rain flux.

Martin, David W.↗
NASA NTRS1990

Use of microwave satellite data to study variations in rainfall over the Indian Ocean

The University of Wisconsin Space Science and Engineering Center mapped rainfall over the Indian Ocean using a newly developed Scanning Multichannel Microwave Radiometer (SMMR) rain-retrieval algorithm. The short-range objective was to characterize the distribution and variability of Indian Ocean rainfall on seasonal and annual scales. In the long-range, the objective is to clarify differences between land and marine regimes of monsoon rain. Researchers developed a semi-empirical algorithm for retrieving Indian Ocean rainfall. Tools for this development have come from radiative transfer and cloud liquid water models. Where possible, ground truth information from available radars was used in development and testing. SMMR rainfalls were also compared with Indian Ocean gauge rainfalls. Final Indian Ocean maps were produced for months, seasons, and years and interpreted in terms of historical analysis over the sub-continent.

Hinton, Barry B.↗