Saturday, September 18, 2010


Jurnal REKAYASA Volume 7 Nomor 1 Artikel 05

Indradhi Lasmana
(Staf Pengajar Politeknik Negeri Kupang)

ABSTRACT: Drought has become one of the annual problems faced by Kupang Regency. Climate, geologic condition, and the quality of Basin do not support the water and land conservation; therefore water and land conservation have become the causes of drought. The consequence of drought is the lack of water for the community and agriculture which in turn decrease the farming production. This research aims at presenting the calculation of the drought index and the analysis of spatial distribution of drought in a map of monthly drought which reveals 3 levels of drought: low, medium, and high and identify the dry regions and the prediction of the widths. The map of drought index derived from the calculation of Drought Index Thornthwaite Method shows that the monthly Drought Index Rate (Ia) Kupang Regency in December to March has Low Drought index (Ia = 0%). Drought Index increases in April, while in May through October water deficit increases where Drought Index is medium to high. The peak of drought happens in September. In November Drought Index gradually decreases to medium and water surplus stars in December.The percentage of Dry Region Width in May varies: low level (12.8%), medium level (86.9%), high level (0.3%). In June it increases: high level (90.6%). In July through October, the region with high level of drought spread equally throughout Kupang Regency. In November, the percentage of dry region width varies once more: low level (13.0%), medium level (66.8%), and high level (20.2%). In December through April most of Kupang Regency’s region has low level of drought.

Keywords: Drought, Drought Index, Thornthwaite Method