| dc.description.abstract | Drought index criteria in a region can be determined by using a method that calculates drought index value of the region. SPI (Standardized Precipitation Index) is a method that can be used to calculate the level of monthly meteorological drought in the region. Rainfall is the main factor affecting the meteorological drought. TRMM satellite provides estimated rainfall data that can be used to calculate the value of meteorological drought index in a region. Validation of estimated rainfall data with observation data showed a positive correlation at convidence interval 95%. Meteorological drought index value of Sumatra Island in 2001 to 2010 ranged from -2.51 to 2.67 indicating the criteria very dry to very wet. Mapping monthly drought index indicates the dominant drought occurred in June and July which happens almost every year except in 2006 on June and 2004 on July. The index also describes dry region in wet months such as November in 2001, 2004, 2006, and 2007 also December in 2001, 2005, 2006, 2007, 2008 and 2010. Areas that often experience drought meteorology of the mapping are North Sumatera, Riau, South Sumatra, and Lampung. Very dry drought criteria in North Sumatra occurred in August 2004 and September 2005, with the region experiencing frequent droughts is part of the south and east of North Sumatra. Very dry conditions in Riau occurred in April 2005 and almost all regions of Riau showed drought especially in May, June, and July even drought also occurred in December, January, and March. Very dry drought criteria occurred in South Sumatra in March 2007 and December 2008. Drought in South Sumatra covers an area to the west, north, and south droughts often occur in May, June, and July. The whole area of Lampung experiencing extremely dry drought criteria in April 2005 and 2008, drought often occurs at the beginning of the year such as February, March, April and May. | en |
