Search Results

You are looking at 1 - 3 of 3 items for

  • Author or Editor: Earl R. Kreins x
  • Refine by Access: All Content x
Clear All Modify Search
William E. Shenx and Earl R. Kreins

Abstract

Cloud Motions were obtained from HRIR measurements contained within the overlapped region of two adjacent Nimbus II orbits. These 108-min averaged motions were compared with instantaneous wind vectors interpolated from constant pressure charts. Corrections for uncertainties in the attitude of the satellite were made by superimposing coastlines that were within the fields of view for both orbits. Cloud mass centroids were determined to estimate the position for each cloud. Cloud top altitudes were obtained from the Nimbus II HRIR data and the isotherms on the constant pressure charts. Generally, the direction and speed of the cloud motions were within 20° and 15 kt of the observed wind direction and speed.

Full access
Jacob Bjerknes, Lewis J. Allison, Earl R. Kreins, Frederic A. Godshall, and Guenter Warnecke

The generally held assumption, that the bulk of tropical rain over the oceans is generated where the sea is warmer than the air, is being largely verified in this article with the new tool of satellite cloudiness mapping. The discussion focuses on the satellite-observed variable position of the boundary between the west Pacific equatorial rain clouds over warm ocean water and the east Pacific aridity along the equator over cool upwelling water. The often quite abrupt changes between these two regimes in the mid-Pacific are known from an eighteen-year sequence of ocean and atmosphere data at Canton Island. This article describes the same phenomena delineated by satellite television data recorded during 1962–67, and adds features of the geographic cloudiness distribution not obtainable from the widely spaced fixed points of observation.

Full access
Guenter Warnecke, Edith I. Reed, Walter B. Fowler, Earl R. Kreins, Lewis J. Allison, and Jaques E. Blamont

Abstract

The presence or absence of clouds, their characteristics, and variations of surface albedo have been correlated with observations made at several different wavelengths in the visible spectrum. These were made at high and low nighttime light levels by an airglow photometer aboard the OGO-4 satellite during August 1967 through January 1968. The wavelength regions studied were approximately 50 Å bands centered at 3914, 5577, 5893, 6225 and 6300 Å, in the energy range of 10−7 to 10−3 erg cm−2 sec−1−1 ster−1 with a field of view of ˜10 degrees. It was found that at the longer wavelengths (6225 and 6300 Å) the observations were strongly influenced by the variations of surface albedo. At the shorter wavelengths, the surface albedo variations were partly masked by the light returned through Rayleigh and Mie scattering. Preliminary analysis is made of surface and clouds by study of reflective radiance under moonlight and other nocturnal illuminations. Possibilities of further analysis are examined including methods of deducing cloud height information.

Full access