Summary
The results of the first step of a project to develop a method to estimate precipitation over the Soudano-Sahelian belt of West Africa are reported.
The study has been performed over the period from 10 June to 9 July 1986 using hourly METEOSAT infrared images. 122 individual cloud clusters associated with squall lines or tropical storms have been tracked. For each event, the time variations of a convection index giving the volume of cloud cooler than −40°C has been determined every hour. The convection index exhibits a strong diurnal cycle. From daily rainfall amounts obtained at about 300 stations, and assuming a time apportion of rainfall within a cloud cluster, the time variations of the hourly total rainfall produced by the cluster can be determined and represents the precipitation index. Because of insufficient rainfall, the precipitation index has been determined for only 17 events. For 2/3 of the 17 cases, there is a significant correlation between the two indices. For each of the 17 events, precipitation has been regressed on the associated convective index and relative time variations. In that case, the results indicate that a convective index representing the life history of the cloud cluster can be calibrated with corresponding raingage measurements provided raingage data are available. Then, estimation of rainfall due to that event over data void regions can be obtained. However, this study shows that no universal relationship exists between precipitation: no rainfall can be estimated if there is not enough raingage measurements to construct a precipitation index for a tracked cloud cluster. This represents a limitation to the method.
Similar content being viewed by others
References
Arkin, P. A., 1979: The relationship between fractional cloud coverage of high cloud and rainfall accumulations during GATE over the B-scale array.Mon. Wea. Rev.,107, 1382–1387.
Barrett, E. C., Martin, D. W., 1981: The use of satellite data in rainfall monitoring. New-York, Academic Press, 340 pp.
Carn, M., Lahuec, J. P., 1987: Estimation des précipitation au Niger au cours de la saison des pluies 1986 à partir de l'imagerie infrarouge METEOSAT. Bilan et critique des méthodes utilisées.Veille Climatique Satellitaire,17, 40–48. Available from Antenne ORSTOM, CMS, BP 147, 22303 Lannion, France.
Carn, M., Dagorne, D., Guillot, B., Lahuec, J. P., 1987: Estimation des précipitations par satellite au Sahel pour la période ma à septembre 1987.Veille Climatique Satellitaire,20, 26–30. Available from Antenne ORSTOM, CMS, BP 147, 22302 Lannion, France.
Desbois, M., Kayiranga, T., Gnamien, B., Guessous, S., Picon, L., 1988: Characterization of some elements of the sahelian climate and their interannual variations for July 83, 84, and 85 from the analysis of Meteosat ISCCP data.J. Climate,1, 867–904.
Duvel, J. P., 1988. Analysis of diurnal, interdiurnal and interannual variations during Northern Hemisphere using METEOSAT infrared channels.J. Climate,1, 471–488.
Duvel, J. P., Kandel, R. S., 1985: Regional-scale diurnal variations of outgoing Infrared Radiation observed by METEOSAT.J. Clim. Appl. Meteor.,24, 335–349.
Gamache, J. F., Houze, R. A. Jr., 1983: Water budget of a mesoscale convective system in the tropics.J. Atmos Sci.,40, 1835–1850.
Griffith, C. G., Augustine, J. A., Woodley, W. L., 1981: Satellite rain estimation in the US hgih plains.J. Appl. Meteor.,20, 53–66.
Griffith, C. G., Woodley, W. L., Grube, P. G., Martin, D. W., Stout, J., Sikdar, D. S., 1978: Rain estimation from geosynchronous satellite imagery. Visible and Infrared studies.Mon. Wea. Rev.,106, 1153–1170.
Houze, R. A. Jr., Betts, A. K., 1981: Convection in GATE.Rev. Geophys. Space Phys.,16, 541–576.
Hubert, P., Thiao, W., Cadet, D., Carbonel, J. P., Desbois M., 1987: Comparaison des données satellitaires infrarouge et des mesures au sol concernant l'épisode pluvieux du 12 au 13 juin 1986 dans la région de Ouagadougou (Burkina-Faso).Veille Climatique Satellitaire,20, 3136. Available from Antenne ORSTOM, CMS, BP 147, 22302 Lannion, France.
Imbernon, J., Assad, E., Guillot, B., Dagorne, D., 1987: Evaluation de la pluviométrie par cumul des images Infrarouge Thermique METEOSAT (Sénégal) 1986.Veille Climatique Satellitaire,16, 49–57. Available from Antenne ORSTOM, CMS, BP 147, 22302 Lannion, France.
Lahuec, J. P., Carn, M., Guillot, B., 1986: Convection et pluviométrie en Afrique de l'ouest. Bilan provisoire pour la saison 1986. ler mai 31 octobre.Veille Climatique Satellitaire,15, 19–23. Available from Antenne ORSTOM, CMS, BP 147, 22302 Lannion, France.
Lamb, J. P., 1985: Rainfall in subsaharan west Africa during 1941–1983.Z. Gletscherkunde und Glaziologie,21, 131–139.
Negri, A. J., Adler, R. F., 1987: Infrared and visible satellite rain estimation. Part II: A cloud definition approach.J. Clim. Appl. Meteor.,26, 1565–1576.
Nicholson, S. E., 1979: Revised rainfall series for the West African subtropics.Mon. Wea. Rev.,107, 620–623.
Omotosho, J. B., 1985: The separate contributions of line squalls, thunderstroms and the monsoon to the total rainfall in Nigeria.J. Climatol.,5, 543–552.
Richards, F., Arkin, P. A., 1981: On the relationship between satellite-observed cloud cover and precipitation.Mon. Wea. Rev.,109, 1081–1093.
Sommeria, G., Testud, J., 1984: COPT 81: a field experiment designed for the study of the dynamics and electrical activity of deep convection in continental tropical regions.Bull. Am. Meteor. Soc.,65, 4–10.
Stout, J. E., Martin, D. W., Sikdar, D. N., 1979: Estimating GATE rainfall with geosynchronous satellite images.Mon. Wea. Rev.,107, 585–598.
Szejwach, G., Desbois, M., 1978: Dynamic classification of mesoscale cloud patterns.J. Appl. Meteor.,17, 1406–1411.
Turpeinen, O. M., Abidi, A., Belhouane, W., 1987: Determination of rainfall with ESOC precipitation index.Mon. Wea. Rev.,115, 2699–2706.
Woodley, W. L., Griffith, C. G., Griffin, J. S., Stromatt, S. C., 1980: The influence of GATE convective rainfall from SMS-1 imagery.J. Appl. Meteor.,19, 388–408.
Author information
Authors and Affiliations
Additional information
With 9 Figures
Rights and permissions
About this article
Cite this article
Thiao, W., Cadet, D.L. & Desbois, M. A note on: Estimation of rainfall due to squall lines over West Africa using meteosat imagery. Meteorl. Atmos. Phys. 42, 69–76 (1990). https://doi.org/10.1007/BF01030579
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF01030579