Govt Prepares Three Weather Strategies for Krakatau Ash

RRI.CO.ID, Jakarta - The Indonesian government, through the National Disaster Management Agency (BNPB), has prepared three weather modification operation (OMC) strategies to reduce the impact of volcanic ash from the Anak Krakatau eruption on weather conditions and air traffic in Lampung, Banten, Jakarta, and West Java.

BNPB Head, Suharyanto said the strategies were prepared based on airspace conditions, the status of the volcanic ash, and aviation safety information. BNPB has kept one OMC team and aircraft on standby at Pondok Cabe Airfield in South Tangerang, in anticipation of the reopening of airspace over Jakarta and surrounding areas.

“Today, we are using three strategies. The first is to keep one team at Pondok Cabe on standby, so that if the airspace is reopened, we can immediately carry out weather modification operations in Jakarta and surrounding areas,” Suharyanto said at a limited meeting on disaster management with President Prabowo Subianto and members of the Red and White Cabinet, Monday, September 7, 2026.

The second strategy is to operate an OMC aircraft from Kertajati Airport in Majalengka, West Java, once the airport is confirmed to be operational. If most of the airspace over Java remains closed, the third strategy is to relocate an OMC aircraft from Kalimantan to Semarang, Central Java.

From Semarang, the weather modification operation will be directed at helping to disperse volcanic ash that could disrupt flights in the four provinces. The implementation of the OMC will continue to be adjusted based on atmospheric and weather conditions, the status of volcanic ash, as well as NOTAMs, or notices concerning airspace conditions and aviation safety.

“We will carry out the OMC from Semarang because Ahmad Yani Airport is not closed. At the very least, this will allow us to conduct weather modification operations to disperse the ash that is currently affecting flights in the four provinces,” Suharyanto said.

The OMC will use two techniques: cloud seeding to increase the potential for rainfall, which can help wash volcanic ash out of the atmosphere, and water mist if suitable rain clouds are unavailable. The latter involves dispersing fine water droplets to help break down and reduce volcanic ash particles in the atmosphere.