Jakarta – The Indonesian government, through intensive collaboration between the National Disaster Management Agency (BNPB) and the Meteorology, Climatology, and Geophysics Agency (BMKG), has successfully demonstrated the effectiveness of weather modification operations to reduce the potential for rainfall in Aceh Province following the hydrometeorological disaster that occurred at the end of 2025. This strategic effort is part of the government’s rapid response in dealing with extreme weather dynamics triggered by natural phenomena such as Tropical Cyclone Senyar, which has caused extraordinarily high rainfall intensity in Aceh and the surrounding areas.
Weather Modification Operations (OMC) are carried out using a fleet of specialized aircraft that seed materials such as Sodium Chloride (NaCl) and Calcium Oxide (CaO) at specific altitudes over Aceh’s airspace. This technology aims to control cloud formation to reduce rainfall intensity and divert it to safer areas, such as the ocean. It also emphasizes the government’s commitment to utilizing science to reduce disaster risk and accelerate recovery.
Abdul Muhari, Head of the National Disaster Data, Information, and Communication Center for the National Disaster Management Agency (BNPB), explained that weather modification operations are the government’s strategic response to extreme weather conditions that threaten public safety. According to Muhari, OMC is being implemented in close coordination with the BMKG (Meteorology, Climatology, and Geophysics Agency) and with full support from the Indonesian Air Force for aircraft and resources.
“This cross-ministerial and institutional weather modification operation serves as mitigation and emergency response support, with the primary goal of reducing potential rainfall in disaster-prone areas by engineering the diversion of rain clouds to safer areas,” Abdul said.
The Director of Public Meteorology at the Meteorology, Climatology, and Geophysics Agency (BMKG), Andri Ramdhani, stated that the operation demonstrated encouraging results amidst the challenges of extreme weather. The latest data shows that the weather modification operation successfully reduced rainfall intensity in Aceh Province by more than 23 percent compared to the initial potential rainfall, thereby accelerating weather stabilization and aiding the recovery process on the ground.
“Weather modification operations in conjunction with the National Disaster Management Agency (BNPB) are currently active in three provinces, and have been proven to reduce rainfall intensity, varying from 15% to 20%. Specifically in Aceh, he explained, the recorded reduction reached 23.35 percent,” said Andri.
Climatology expert from the Bandung Institute of Technology, Prof. Dr. Siti Nurhayati, stated that the implementation of weather modification technology led by the Indonesian government is a form of adaptive innovation to increasingly dynamic climate change.
“The government’s efforts to integrate BMKG data and BNPB’s implementation of weather modification operations are concrete examples of how the government is using technology to protect the public from the risks of extreme weather. This is not only disaster mitigation, but also a preventative measure that reduces the socioeconomic costs of hydrometeorological disasters,” said Prof. Siti.
In line with the latest BMKG data, weather forecasts for Aceh and the North Sumatra region now show a more stable trend, with a predominance of light to moderate rainfall in recent weeks, providing room for accelerated post-flood response, including the construction of temporary housing and repair of affected infrastructure.
The success of this weather modification operation is a clear demonstration of inter-agency cooperation under the coordination of the central government in addressing the challenges of climate change and hydrometeorological disasters. With strong synergy of technology and policy, the government demonstrates that protecting the public remains a top priority, while strengthening national resilience against future disaster threats.*