期刊名称：Science et changements planétaires / Sécheresse
印刷版ISSN：1147-7806
电子版ISSN：1777-5922
出版年度：2006
卷号：17
期号：4
页码：467-474
DOI：10.1684/sec.2006.0057
出版社：John Libbey Eurotext
摘要：Figures See all figures Authors Daniel Nuñez López , Carlos Alfonso Muñoz Robles , Héctor Gadsden , Victor Manuel Reyes-Gómez Centro de Investigación Sobre Sequía (CEISS), Instituto de Ecología, A.C., Chihuahua, Km 33.3, Carret. Chihuahua-Ojinaga, C.P. 32900, Cd. Aldama, Chihuahua, México Key words: climatology, drought, indices, rainfall, Mexico DOI : 10.1684/sec.2006.0057 Page(s) : 467-74 Published in: 2006 During the last thirty years, the occurrence and distribution of rainfall in the State of Chihuahua (Mexico) has been very irregular. At state level, a historical average of 419mm of precipitation is registered annually. Nevertheless, since 1993, precipitation has appeared below of the historical average, and this is one of the reasons why water availability is limited in Chihuahua. This paper describes the main characteristics of the drought events which occurred in Chihuahua during the period from 1970 to 2000. The analysis is based on the SPI calculation from several time scales: short term (3 months), median term (12 months) and long term (24 months). For each one of the climatic regions in Chihuahua, the frequency, duration and intensity of drought events was determined on these time scales. The SPI values observed for the short-term scale vary a great deal in keeping with the changes in the rainfall amounts, whereas at median and long-term scales the SPI values remained stable and showed clearly the precipitation excess and deficit. In terms of the short-term scale analysis, the drought events identified were characterized as being more frequent and of short duration, in contrast with the median and long-term scales, where the drought events appeared less recurrent but more prolonged. The most extraordinary drought events considering their intensity, duration, and geographic extent occurred in the three climatic regions and at the end of the 1990s.
