The effectiveness of WMT activities to reduce hotspots during El-Nino in 2014–2015 in Ogan Komering Ilir District, South Sumatra

Smoke disasters caused by land and forest fires tend to very often occur in peatlands during dry season. Dry season occurs during periods in which rain intensity decreases, causing the land to dry and become prone to burn. Weather modification technology, or WMT, is an alternative solution that can increase rain intensity in a region during dry season by adding NaCl into potential rain clouds. This paper discusses the effectiveness of using WMT during weak El-Nino year in 2014 and strong El-Nino year in 2015 in Ogan Komering Ilir District (Kab. OKI), a region containing numerous peatlands in South Sumatra Province. This study uses track seeding data to determine the location of potential cloud seeding, humidity data to assess the level of atmospheric drought in the region, and rain and hotspot data to analyze the effectiveness of cloud seeding activities in the study period in Kab. OKI. The study results obtained during September–November 2014 and 2015 proved that WMT had been considerably useful, considering that Kab. OKI had relative increase in rainfall intensity and decrease of hotspots during that period. The year 2014 was classified as having weak El-Nino period, in which the rainfall gradient was positive (0.0348) and the gradient hotspot was negative (−0.3846). The same incident occurred in 2015 during a strong El-Nino.