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Miller, J. R., Jr.

Publications and source records attributed to Miller, J. R., Jr..

Rain Volume Estimation over Areas Using Satellite and Radar Data

The application of satellite data to a recently developed radar technique used to estimate convective rain volumes over areas on a dry environment (the northern Great Plains) is discussed. The area time integral technique (ATI) provides a means of estimating total rain volumes over fixed and floating target areas of the order of 1,000 to 100,000 km(2) for clusters lasting 40 min. The basis of the method is the existence of a strong correlation between the area coverage integrated over the lifetime of the storm (ATI) and the rain volume. One key element in this technique is that it does not require the consideration of the structure of the radar intensities inside the area coverage to generate rain volumes, but only considers the rain event per se. This fact might reduce or eliminate some sources of error in applying the technique to satellite data. The second key element is that the ATI once determined can be converted to total rain volume by using a constant factor (average rain rate) for a given locale.

Doneaud, A. A.↗

Convective rain rates and their evolution during storms in a semiarid climate

The semiarid climate of the U.S. northern High Plains region has been studied with respect to rain rates and their evolution during summertime convective storms, using radar data from a total of 750 radar echo clusters. Analysis of this data suggests that the average rain rate R among storms is in a first approximation independent of the total rain volume, if the entire storm duration is considered in the averaging process. R primarily depends on the reflectivity threshold considered in calculating the area coverage integrated over the lifetime of the storm. R evolution during storms is analyzed by dividing each storm lifetime into 10 min, 1, 2, and 4 hours, as well as growing and decaying periods. The value of R remained independent of the total rain volume when the growing or decaying periods of storms were considered separately.

Doneaud, A. A.↗

An attempt to extend the ATI technique to estimate convective rain volumes using satellite data

Digital satellite and radar data of a thunderstorm event that occurred on June 12, 1981 are examined. The processing of both data sets is described. Cumulative area versus count values, and threshold count values for IR and visible satellite data for 13 consecutive time steps are analyzed. The IR and visible satellite images are compared. The relation between radar reflectivity, temperature, and echo height is studied.

Doneaud, A. A.↗