All-sky measurements of short period waves imaged in the OI (557.7 nm), Na(589.2 nm) and near infrared OH and O2(0,1) nightglow emissions during the ALOHA-93 campaign, Geophys. Res. Lett., 22, 2833Lett., 22, , 1995 Abstract. As part of the ALOHA-93 campaign a high performance all-sky CCD imaging system was operated at Haleakala Crater, Maui, to obtain novel information on the properties and sources of short period gravity waves over an extended height range -80-100 kin. Sequential observations of the near infrared OH and O2(0,1) bands and the visible wavelength OI(557.7 nm) and Na(589.2 nm) line emissions have enabled a unique comparison of the morphology and dynamics of the wave motions and their occurrence frequency at each emission altitude to be made. Two major findings are: (a) the detection of significanfly higher amounts of wave structure at OI altitudes (-96 lena) compared with that in the OH emission (-87 kin) and (b) the discovery of an unusual morphology, small-scale wave pattern that was most conspicuous in the OI emission and essentially absent at OH heights. These data provide strong evidence for the presence of ducted wave motions in the lower thermosphere.

Data from the scanning channels of the NIMBUS 7 Earth Radiation Budget (ERB) experiment are combined with other data on earth surface conditions and cloudiness. Patterns of bi-directional reflectance are constructed from this data for uniform earth and cloud surfaces. Examples are shown that illustrate the bi-directional properties of surfaces and how these properties vary with solar zenith angle (SZA). Dependence of albedo on SZA is also shown. Conclusions may be summarized as follows: (1) Water surfaces exhibit limb brightening at all SZAs; (2) cloud and land surfaces change from limb darkening to brightening as SZA increases; (3) the land surface exhibits higher backward reflection for SZAs less than about 50ø; (4) all of the surfaces in this study become more specular as SZA increases; (5) snow is the most nearly isotropic of these surfaces; (6) snow albedo shows very little variation with SZA and even shows a slight decrease over a limited range; (7) albedo generally increases with increasing SZA for other than snow surfaces; (8) angular patterns for high water and ice clouds are quite similar, but ice clouds are more nearly isotropic; (9) the angular patterns developed in this study are in qualitative agreement with those from other investigations.

No abstract

Radiation pressure due to sunlight anisotropically reflected from the oceans apparently cannot explain the fluctuations in the anomalous along-track deceleration of the LAGEOS satellite. It fails by about a factor of 2 to account for the major peaks in the acceleration. This result is based on an extreme model: a cloudless earth whose northern hemisphere consists of continent and whose southern hemisphere consists of ocean. The continent is assumed to reflect sunlight according to Lambert's law, while the ocean reflects anisotropically according to a simple analytical law which mimics Nimbus 7 observations. The inclusion of clouds into the model would reduce the acceleration to perhaps an order of magnitude below those observed. Some other explanation for the fluctuations, which have magnitude •2 x 10-•2 m s-2, must be sought.

Satellite cloud picture data received from the vidicon sensors of the ESSA satellite are digitized and a reduced meso-scale archive is produced. The meso-scale archival data tape is described. Computer-derived products of the meso-scale archive, which include time averages and composites, are shown and discussed.