Comparison of CMORPH and TRMM-3B42 over Mountainous Regions of Africa and South America
Two satellite rainfall estimation algorithms, CMORPH and TMPA, are evaluated over two mountainous regions at daily accumulation and spatial resolution 0.25°. The evaluated TMPA products are TRMM-3B42 and TRMM-3B42RT. The first of the two validations region is located over the Ethiopian highlands in the Horn of Africa. The second is located over the highlands of Columbia in South America. Both sites are characterized by a very complex terrain. Relatively dense station networks over the two sites are used to validate the satellite products. The correlation coefficients between the reference gauge data and the satellite products were found to be low. Besides, the products underestimate both the occurrence and amount of rainfall over both validation sites. These were attributed, at least partly, to orographic warm rain process over the two regions. The performance over Colombia was better compared to that for Ethiopia. And CMORPH has exhibited better performance as compared to the two TRMM products.
KeywordsSatellite Rainfall estimation Passive microwave Infrared Validation
We are very grateful to the National Meteorological Agency (NMA) of Ethiopia, and the Meteorological Service of Colombia (IDEAM) for providing the rain gauge data free of any charge.
- Gruber, A. and V. Levizzani, 2008: Assessment of Global Precipitation Products, WMO/TD-NO. 1430, (Available online at: http://www.isao.bo.cnr.it/~meteosat/papers/AssessmentGlobalPrecipitation-2008.pdf)
- Huffman, G. J., R. F. Adler, D. T. Bolvin, G. Gu, E. J. Nelkin, K. P. Bowman, Y. Hong, E. F. Stocker, and D. B. Wolf, 2007: The TRMM multisatellite precipitation analysis (TMPA): Quasi-global, multiyear, combined-sensor precipitation estimates at fine scales. Journal of Hydrometeorology, 8, 38–55.CrossRefGoogle Scholar
- Hurtado, G., 2005: Precipitation in Colombia. Climate Atlas of Colombia. IDEAM Bogotá, ColombiaGoogle Scholar
- Levizzani, V., R. Amorati, and F. Meneguzzo, 2002: A Review of Satellite-based Rainfall Estimation Methods, Consiglio Nazionale delle Ricerche Istituto di Scienze dell'Atmosfera e del Clima, (Available online at http://www.isao.bo.cnr.it/~meteosat/papers/MUSIC-Rep-Sat-Precip-6.1.pdf)
- Levizzani, V., Bauer, P., and Turk J. F. (Eds.),, 2007: Measuring Precipitation from space: EURAINSAT and the Future. Springer, New York, 724 pp..Google Scholar
- Schneider, U., T. Fuchs, A. Meyer-Christoffer, and B. Rudolf 2008: Global precipitation analysis products of the GPCC. Available online at: (http://gpcc.dwd.de).
- Xie, P., Y. Yarosh, T. Love, J. Janowiak, and A. Arkin 2002: A real-time daily precipitation analysis over southern Asia. Preprints, 16th Conf. of the Hydro., Orlando, FL, Amer. Meteor. Soc.Google Scholar