RECENT STUDY ON DROUGHT VARIATION IN MALAWI

Author: Noel Banda and Prof.Lu hao

Accurate detection and identification of meteorological drought variation in space and time is fundamental for alleviation and reduction of drought and take scientific measures reducing the adverse impact further at local and global scales.  This study used monthly rainfall to generate Standardize Precipitation Index (SPI) as an indicator of drought or wetness at various time scales (1 to 6 months) to understand and determine the temporal and spatial distribution of drought for the past five decades in Malawi. The Empirical Orthogonal Function (EOF) analysis was also applied to examine the temporal and spatial characteristics and to identify the dominant pattern of rainfall variability from 1981 to 2010. 

The SPI findings show that the period of 1960 to 1989 was dominated by wetness while the period after 1990 was dominated by dry conditions. The results of Principal Component (PC) of EOF indicate that the first pattern accounts for 52.8 and 53.1% of the precipitation variability for NDJ and FMA season respectively, which can reflects the general dry or wet spatial patterns of Malawi. The whole country shows consistent dry or wet variation in general during the recent thirty years. The precipitation dynamic in southeastern part is the most sensitive area and the annual precipitation trend of the whole country is dominated by this region. 

The temporal series of the first EOF in NDJ and FMA both show a large inter-annual variability, but dry years, especially for the severe dry years, is increasing after 1990. Overall, both EOF and SPI analysis clearly reveal that the drought situation has been increased during the past decades and the entire country becomes drier after 1990. Findings from this study are useful for alleviation and reduction of drought disaster losses and take scientific measures reducing the adverse impacts in the study region.