Visible Satellite Imagery Research Articles

Algorithm for automatic atmospheric corrections to visible and near-IR satellite imagery

An algorithm for automatic atmospheric correction of satellite imagery of the earth's surface is proposed which is applicable to low-resolution and high-resolution imagery of land areas. The algorithm is based on the satellite image being corrected and on the climatology of the area, and it requires that some pixels in the image correspond to dense dark vegetation as the surface cover. The algorithm is sensitive to the assumed reflectance of the dense dark vegetation, and the accuracy of the corrected surface reflectance is expected to be + or - 0.01. Using the method, aerosol optical thicknesses were derived from clear and hazy Landsat MSS images in the Washington, D.C. and Chesapeake Bay region, and the results are found to agree well with simultaneous sunphotometer ground measurements.

Use of Enhanced IR/Visible Satellite Imagery to Determine Heavy Snow Areas

Abstract Interpretation techniques are established which relate heavy snow (100 mm or more in a 12 h period) areas to real-time infrared and visible geostationary satellite imagery. An initial collection of cases totaled about 75 during the period from the fall of 1979 to the spring of 1984. The main area of concern extended from the Rockies to the Appalachians. By using conventional surface and upper air data and numerical model output from the LFM-II relationships were established between heavy snow occurrences and cloud patterns in the satellite imagery. The different cloud patterns and flow regimes suggest a classification of heavy snow events into four main types: High Plains cyclogenesis, northwest and southwest flow short-wave troughs, and orographic. Each type has preferred geographical locations, common snowfall durations, storm totals, and band widths and lengths. The snowfall maximum with each storm is influenced by the strength and movement of the system and the structure of the moist layer. S...

Comparison of Northern Hemisphere Snow Cover Data Sets

Abstract Four Northern Hemisphere snow cover data sets are compared on a weekly basis for the 25-month period, July 1981 through July 1983. The data sets are the NOAA/NESDIS Weekly Snow and Ice Chart, the Composite Minimum Brightness (CMB) Chart, the U.S. Weekly Weather and Crop Bulletin (data only for North America), and Air Form data. The NOAA/NESDIS chart is produced through the use of photo-interpretation of visible satellite imagery and ground observations. The U.S. Crop Bulletin is also done manually, using only ground observations. The CMB chart and the Air Force data are both produced using automated processes, the first by way of visible satellite imagery and the second by way of ground observations, climatology, satellite observations and persistence. Since the NOAA/NESDIS chart is the only standard and complete data set dating back to the mid 1960s, it is used as the basis for the study. The main emphasis of this paper is a comparison of the CMB and the NOAA/NESDIS chart. The CMB frequently ove...

Effects of Enhanced Initial Moisture Fields on Simulated Rainfall over West Africa and the East Atlantic

Numerical simulations of a 24-h period during GATE are performed to evaluate the impact of enhanced initial moisture fields on short range forecasts of tropical rainfall. The domain covers West Africa and most of the eastern half of the Atlantic Ocean. A version of the Pennsylvania State University Mesoscale Model is used, and results are verified against satellite rainfall estimates. The initial moisture fields are enhanced subjectively using visible satellite imagery, available rawinsonde soundings and monthly mean soundings. The rainfall forecasts with initial moistures enhanced throughout the analysis region clearly outperform forecasts which use either the unaltered initial moisture analysis or an analysis performed with selectively enhanced moisture soundings. The former produce better zonal and meridional distributions of rain, narrower and more intense intertropical convergence zone (ITCZ) regions and stronger local maxima in agreement with verification. The success of the relatively simple moisture enhancement used in this study suggests that satellite-enhanced moisture analyses will have a major impact on short-range numerical forecasts of tropical rainfall.

Remote Assessment of Ocean Color for Interpretation of Satellite Visible Imagery: A review: By H. R. Gordon and A. Y. Morel. Springer‐Verlag, Berlin, 1983. Pp. 114. DM 58 (approx. US$22.5)

Quarterly Journal of the Royal Meteorological SocietyVolume 111, Issue 469 p. 872-872 Review Remote Assessment of Ocean Color for Interpretation of Satellite Visible Imagery: A review: By H. R. Gordon and A. Y. Morel. Springer-Verlag, Berlin, 1983. Pp. 114. DM 58 (approx. US$22.5) I. S. Robinson, I. S. RobinsonSearch for more papers by this author I. S. Robinson, I. S. RobinsonSearch for more papers by this author First published: July 1985 https://doi.org/10.1002/qj.49711146913Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume111, Issue469July 1985Pages 872-872 RelatedInformation

The Presidents' Day Cyclone of 18–19 February 1979: Influence of Upstream Trough Amplification and Associated Tropopause Folding on Rapid Cyclogenesis

The Presidents' Day cyclone of 18-19 February, 1979 is analyzed based on conventional radiosonde data, infrared and visible satellite imagery, water vapor images and ozone measurement. The well-known synoptic-scale characteristics of the PJ-trough system are described, and evidence for the development of the tropopause fold are presented. Processes contributing to the formation of the fold are discussed in terms of an evaluation of the Sawyer-Eliassen circulation equation and a diagnostic evaluation of the ageostrophic winds and vertical motion near the polar jet streak. The documentation of stratospheric extrusions and their possible role in cyclogenesis is reviewed, and Eulerian and Lagrangian diagnostics are used to establish a connection between the tropopause fold associated with the polar jet streak and rapid cyclogenesis along the East Coast. Conservation of potential vorticity expressed in isentropic coordinates is used as a constraint from which to view cyclogenesis.

Oceanographic implications of features in NOAA satellite visible imagery

The sunglint areas of the ocean in NOAA satellite visible imagery appear as long swaths that extend from the northern extremes of the North Temperate Zone to the southern extreme of the South Temperate Zone. Examples are shown of complex features apparent in the sunglint area of visible imagery that closely match ocean-related thermal features in the companion infrared imagery. Various interpretations of these features are discussed. Data from the first phase of the Grand Banks Experiment (June 1978) are presented which demonstrate that such sunglint features are related to the strong ocean frontal processes present in this area. Although some of the features may be associated with fog or mist, side-looking airborne radar imagery collected during the experiment confirms the presence of surface roughness variations. The observations strongly suggest that these roughness variations are due to changes in the stability of the atmospheric boundary layer caused by the different surface water temperatures present in the area. The results demonstrate the usefulness of NOAA visible imagery as a tool to aid in the understanding of synoptic ocean processes, and suggest an important application for satellite and airborne synthetic aperture radars in mapping the roughness changes associated with ocean current systems.

Rain Estimation from Geosynchronous Satellite Imagery—Visible and Infrared Studies

Abstract A diagnostic method to estimate rainfall over large space and time scales by the use of geosynchronous visible or infrared satellite imagery has been derived and tested. Based on the finding that arms of active convection and rainfall in the tropics are brighter or colder on the satellite visible or infrared photographs than inactive regions, ATS-3 and SMS/GOES images were calibrated with gage-adjusted 10 cm radar data over south Florida. The resulting empirical relationships require a time sequence of cloud area, measured from the satellite images at a specified threshold brightness or temperature to calculate rain volume over a given period. Satellite rain estimates were made for two areas in south Florida that differ in size by an order of magnitude (1.3×104km2 vs 1.1×105km2) and verified by a combined system of gages and radar. Contrary to our expectations, the rain estimates for the smaller area agreed better with the raingage-radar groundtruth than the satellite rain estimates for the large...

Locating and interpreting hand-held photographs over the ocean; a Gulf of Mexico example from the Apollo-Soyuz Test Project

Hand-held photographs from the Apollo spacecraft, taken over the eastern Gulf of Mexico in July 1975, are evaluated for their oceanic information. The photographs are located over the open sea by comparing cloud formations in simultaneously acquired geostationary satellite visible imagery. Using concurrently obtained ship data, patterns in the sunglint were interpreted as indicators of the cyclonic shear zone of the Gulf Loop Current. A hypothesis that frequently observed circular cloud features were indicators of mesoscale turbulence in ocean currents (Stevenson, 1974) was tested; it was found that the features could be consistently explained as being atmospheric (only) in nature and are not associated with cold core ocean eddies.

Satellite and Surface Observations of Strong Wind Zones Accompanying Thunderstorms

This paper describes how the strength of thunderstorm gut fronts can frequently be determined from the satellite-derived speed of the clouds associated with the gust front and the appearance of the cloud patterns on the visible and enhanced IR satellite imagery. Rapidly moving gust fronts are generally associated with strong surface wind speeds, with the strongest winds located in the portion of the arc boundary closest to the most vigorous convection. The region of most vigorous convection can be pinpointed by the cloud-edge gradients and the appearance of the anvil cirrus on enhanced infrared imagery. The relationship between cloud patterns and gust front strength was obtained by plotting surface wind data on 1 and 2 km resolution visible satellite imagery. The speeds of the clouds associated with the gust fronts were determined using an image analyzer with a video disk capable of storing images and displaying them in motion.