1987 .

(2 publications)

L. Picon, M. Desbois, and G. S├Ęze. Use of meteosat ISCCP B2 data for the study of interannual variations of climatic elements in Africa. Advances in Space Research, 7:199-202, 1987. [ bib | DOI | ADS link ]

Composite monthly images corresponding to West African rainy seasons of 1983, 1984, and 1985, have been constructed from ISCCP B2 Meteosat data. Average and standard deviation images from thermal infrared and water vapor channels are studied. In the thermal infrared, differences between the three years appear principally in the mean structure of the ITCZ, North-South extend, northward boundary, longitudinal variations of the convection. In the water vapor channel, well defined “dry” areas appear, showing the location and extent of subsidence regions on a large scale. These locations and extents also vary from year to year.

T. Kayiranga, M. Desbois, and L. Picon. Diurnal variations of convective cloudiness in tropical Africa observed with Meteosat ISCCP B2 data. Advances in Space Research, 7:163-166, 1987. [ bib | DOI | ADS link ]

Monthly composite images have been constructed from 8 times of the day from the ISCCP B2 Meteosat data set. Average and standard deviation images in IR and WV channels have been constructed at first. These images allow to describe the mean diurnal cycle of convection over Africa, and show that this cycle is strongly influenced by the orography. Comparisons between two very different rainy seasons in West Africa, 1983 and 1985, show some differences in the diurnal cycles.