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Barrett, E. C.

Publications and source records attributed to Barrett, E. C..

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

The Bristol method of satellite-improved rainfall monitoring

Remote sensing estimates of area average precipitation are useful to agricultural and climatological applications. Estimates obtained by active or passive microwaves, infrared and visible sensors may be augmented and improved using indirect measures of precipitation, such as the change in near surface soil moisture content caused by a particular event. Measurements of soil moisture using infrared radiances do not provide precipitation information in real time since the sky must clear. However, the resultant estimate of precipitation is a time integrated value which provides a significant savings in data handling and can overcome virtually all of the sampling problems associated with the monitoring of precipitation through storms of long duration.

Barrett, E. C.↗
NASA NTRS1977

Analyses of the cloud contents of multispectral imagery from LANDSAT 2: Mesoscale assessments of cloud and rainfall over the British Isles

The author has identified the following significant results. It was demonstrated that satellites with sufficiently high resolution capability in the visible region of the electromagnetic spectrum could be used to check the accuracy of estimates of total cloud amount assessed subjectively from the ground, and to reveal areas of performance in which corrections should be made. It was also demonstrated that, in middle latitude in summer, cloud shadow may obscure at least half as much again of the land surface covered by an individual LANDSAT frame as the cloud itself. That proportion would increase with latitude and/or time of year towards the winter solstice. Analyses of sample multispectral images for six different categories of clouds in summer revealed marked differences between the reflectance characteristics of cloud fields in the visible/near infrared region of the spectrum.

Barrett, E. C.↗
NASA NTRS1976

Comparisons of cloud cover evaluated from LANDSAT imagery and meteorological stations across the British Isles

The author has identified the following significant results. This stage of the study has confirmed the initial supposition that LANDSAT data could be analyzed to provide useful data on cloud amount, and that useful light would be thrown thereby on the performance of the ground observer of this aspect of the state of the sky. This study, in comparison with previous studies of a similar nature using data from meteorological satellites, has benefited greatly from the much higher resolution data provided by LANDSAT. This has permitted consideration of not only the overall performance of the surface observer in estimating total cloud cover, but also his performance under different sky conditions.

Barrett, E. C.↗
NASA NTRS1976

The identification of cloud types in LANDSAT MSS images

The author has identified the following significant results. Five general families of clouds were identified: cumulonimbiform, cumuliform, stratiform, stratocumuliform, and cirriform. Four members of this five-fold primary division of clouds were further divided into a number of subgroups. The MSS observed and recorded earth radiation in four different wavebands. Two of these bands (4 and 5) image in the visible portion of the electromagnetic spectrum, while the others (6 and 7) image the short wave portion, or just into the infrared. The main differences between the appearances of clouds in the four wavebands are related to the background brightness of land and sea surfaces.

Barrett, E. C.↗