Jean-Marie Monget

A method for the determination of the global solar radiation from meteorological satellite data

Abstract A statistical method is presented for the determination of the global solar radiation at ground level. It makes use of data from the meteorological satellites, which provide extensive coverage as well as adequante ground resolution. In the first step, a reference map of ground albedo is deduced from the time-sequence of satellite images. Then, by comparing the satellite data with the computed albedo map, a cloud coverage index is determined for each ground point of 5 km × 5 km. This index is linearly correlated to the atmospheric transiission factor. The regression parameters are estimated using a training set provided by ground pyranometers. Tests for two different time periods show a good agreement between the actual and model-derived hourly global radiation.

A Comparison between Infrared Satellite Images and Sea Truth Measurements

A method for processing NOAA-VHRR and TIROS N-VHRR data is outlined. Noise elimination is performed and sea surface temperature maps are produced with a maximum temperature resolution of 0.5°C. A comparison is shown between in situ temperature measurements and VHRR radiometric temperatures along a track intersecting the cyclonic gyre of the Liguro-Provencal basin. The ecologic significance of the observed thermal fronts is demonstrated by stations showing the vertical variations of oceanographic parameters. The satellite image allows apprehension of the two dimensional geometry of these fronts. This information can be used in the evaluation of the primary production of the basin. It is also emphasized that the systematic processing of I.R. images brings a significant contribution to the planning of future oceanographic cruises.