Enviro News Asia, Jakarta – Weather modification in Indonesia has evolved for nearly five decades, moving from the concept of “artificial rain” to Weather Modification Technology (TMC) and subsequently Weather Modification Operations (OMC). This transition reflects more than a shift in terminology; it demonstrates a functional pivot from technology development toward operational execution to support disaster management and water resource management.
This evolution now presents new challenges for Indonesia. Following institutional restructuring involving BPPT, BRIN, and BMKG, the research and operational functions of weather modification have grown increasingly separated. This situation creates a critical need to ensure that technology, knowledge, observation, operations, and evaluation remain interconnected so that OMC does not turn into a routine exercise lacking a reinforced scientific foundation.
Climate, environmental, and geospatial observer A. Karsidi, in his study on the development of weather modification in Indonesia, notes that the shift from TMC to OMC must be viewed as more than a simple change in nomenclature. According to Karsidi, TMC is a comprehensive system comprising knowledge, methods, equipment, engineering, research, and evaluation, whereas OMC represents the application of that technology for specific operational objectives.
“OMC is the application of TMC,” Karsidi writes in his study. He emphasizes that weather modification operations should serve as the spearhead of a mature technology, rather than a replacement for the technology development process itself.
Historically, the concept of weather modification in Indonesia began to take root in the 1970s. Artificial rain experiments were conducted in 1977 in regions such as Bogor, Sukabumi, and Solo, following insights gained from Thailand’s experience. Institutionally, these activities initially operated under Pertamina’s Advanced Technology Division before transferring to BPPT in 1978, officially becoming the BPPT Artificial Rain UPT in 1985.
In the early phase, the term “artificial rain” prioritized the desired outcome. Scientifically, however, the term was considered inaccurate regarding the actual process. Weather modification does not create rain from an unpromising atmosphere; rather, it influences microphysical processes within pre-existing clouds that meet specific criteria to make precipitation more effective.
The shift toward TMC expanded the scope of activities. The technology came to encompass atmospheric physics and cloud microphysics, seeding methods, seeding materials, operational platforms, observation and prediction systems, as well as scientific evaluation methods. Consequently, weather modification extended beyond flights and cloud seeding into a broader system of knowledge and technology.
During the BPPT era, this ecosystem advanced through method development, experimentation, effectiveness testing, field operations, equipment and material development, and the establishment of evaluation methodologies. Ideally, every operation yielded both practical benefits and new insights to refine the technology for subsequent missions.
Technological advancement was also evident in seeding methods, which progressed from hygroscopic materials like powdered NaCl to the use of flares. Flare technology began development around 2005 during operations in Soroako. Reliance on imported products prompted a collaboration with PT Pindad to produce the local CoSat flare, which secured a patent in 2009. Over the same period, geographic information systems, weather radar, remote sensing, and various observation systems advanced to improve operational precision.
The scope of weather modification widened accordingly. Initially focused on augmenting rainfall and reservoir inflow to support irrigation and hydroelectric power generation, its application expanded in 1997 to mitigate haze and forest fires, as well as manage floods and landslides. This shift marked a transition from simple rainfall enhancement to hydrometeorological risk management.
Following BPPT’s integration into BRIN, a clearer separation emerged between research and operational roles. Within the framework outlined by Karsidi, BRIN focuses on science and technology development, while BMKG handles operational functions supported by a network of meteorological observation, weather radar, satellites, and forecasting systems. This division further reinforced the use of the term OMC.
According to Karsidi, the primary challenge following this restructuring is ensuring the continuity of the weather modification knowledge base. Several critical questions remain: who develops the underlying technology for OMC, who researches cloud microphysics and next-generation seeding agents, who builds numerical targeting models, and who conducts independent evaluations of operational success?
These issues are vital because OMC success cannot be determined by a simple correlation between seeding and subsequent rainfall. The atmosphere is a dynamic system with high natural variability. Therefore, evaluations must distinguish between rain resulting from intervention and rain that would have fallen naturally. The study recommends an evaluation sequence encompassing meteorological baselines, predictions, interventions, observations, attribution, and verification.
Karsidi also calls for the development of 21st-century technology-driven OMC. Such a system would leverage dual-polarization weather radar, meteorological satellites, high-resolution atmospheric models, data assimilation, artificial intelligence and machine learning, GNSS meteorology, lidar, disdrometers, and GIS. These technologies can help characterize cloud properties, perform nowcasting, pinpoint intervention targets, and evaluate operational impacts in a more measurable manner.
In the context of forest and land fires, weather modification must shift from a reactive response after fires occur to an integral component of climate risk management. Data on ENSO, IOD, seasonal trends, and hydrological conditions across peatlands, reservoirs, retention ponds, and watersheds can identify risks prior to the dry season. OMC can then be executed when atmospheric conditions present viable opportunities for intervention.
This approach situates OMC within broader watershed and water cycle management. Rain induced through atmospheric intervention must be evaluated based on where precipitation falls, its impact on river basins, infiltration, groundwater, rivers, reservoirs, and subsequent water demand. Thus, weather modification moves beyond whether rainfall increases or decreases to focus on how interventions contribute to national water security.
To sustain this framework, the study proposes a national ecosystem linking research, technology, operations, and evaluation. BRIN and universities can strengthen research and experimentation, BMKG can lead observation, forecasting, targeting, and operations, while independent evaluations and scientific publications feed into the next cycle of technology development.
Ultimately, Karsidi underscores that Indonesia does not need to pit TMC against OMC. The core objective is ensuring that operations remain anchored to a robust, continuously evolving technological foundation. “OMC must be understood as the operational application of a technology system that is continuously advanced through scientific research, observation, modeling, experimentation, and evaluation,” he writes.
With nearly half a century of experience, Indonesia possesses valuable assets: skilled human resources, field experiments, seeding material technology, radar and modeling expertise, and diverse applications for water security and disaster mitigation. The next imperative is not merely scaling up operations, but safeguarding and advancing the accumulated knowledge to address increasingly complex challenges in climate, water, flooding, drought, and forest fires. (*)
