Why Is Hydrometeorological Disaster Increasing?

JAKARTA - A hydrometeorological disaster is one of the disasters that often hit various regions in Indonesia. Usually, the Meteorology, Climatology and Geophysics Agency (BMKG) reports warnings regarding hydrometeorological disasters in the end of the year before the new year. Unfortunately, just entering March, several parts of Indonesia, including Jabodetabek, have actually been hit by floods that are included in hydrometeorological disasters.

Quoted from the UGM Hydrometeorological Module, for the last 20 years Indonesia has experienced various types of natural disasters, including hydrometeorological disasters. The trend of hydrometeorological disaster phenomena in Indonesia has a tendency to increase from year to year. Senior researcher from the Center for Climate Disaster and Change Mitigation Research, Institute of Technology Ten November (ITS) Surabaya, Amien Widodo revealed, hydrometeorological disasters are often caused by climate change.

Hydrometeorological disasters themselves are phenomena of natural disasters or destructive processes that occur in the atmosphere (meteorology), water (hydrology), or ocean (oceanography) caused by meteorological parameters, such as rainfall, humidity, temperature, and wind. The impact of hydrometeorological disasters can cause loss of life, injury or other health impacts, such as damage to property, loss of livelihoods and services, social and economic disturbances, or environmental damage.

Since 1,800 until now, hydrometeorology has been a disaster that has occurred a lot in Indonesia, followed by geological activities such as earthquakes and volcanic eruptions. Nearly 90-95 percent is a hydrometeorological disaster. The remaining 5-10 percent is earthquakes and volcanic eruptions," said Amien, Monday, March 10, 2025.

He assessed that the occurrence of damage to watersheds, urbanization, poverty and socio-cultural factors would certainly increase the threat of hydrometerological disasters. In addition, the influence of global climate change also has an impact on increasing hydrometeorological disasters in Indonesia. However, anthropogenic factors are seen as the most dominant in contributing to the increase in floods and droughts compared to global climate change factors. Human behavior factors are still dominant compared to other factors as the cause of hydrometeorological disasters," added Amien.

Meteorogi and climatology expert from the National Research and Innovation Agency, Edvin Aldrian, revealed that the cause of hydrometeorological disasters in Indonesia is the entry of warm water into Indonesian waters. As a result, there has been more cloud formation. This natural phenomenon is driving the increase in the intensity of rain in Indonesia which makes the rainy season bigger than ever before.

"Various studies have shown that the threat of hydrometeorological, climate, weather and water-related disasters such as hurricanes, droughts and floods is calculated for the largest number of natural disasters around the world and affects more people than other types of natural disaster threats," he said.

He explained, several studies show that climate change in Indonesia has brought changes to local season patterns. The average amount of rain in the rainy season (October-March for the Java region) is 80 percent of the annual amount of rain. Changes in the season pattern occurred with increasing dry season and increasing the ratio of the amount of rain in the rainy season to dry season which increased above 80 percent. This condition is further exacerbated by the persistent decrease in total annual rain accumulation in almost all parts of Indonesia in the last five decades so that the potential for water to be reduced.

In addition, the increase in hydrometeorological disasters is not only caused by global climate change, but also due to environmental management errors. Global climates continue to change due to human activities. Environmental degradation due to human activities causes increased hydrometeorological disasters," added Edvin.

The Greenpeace Indonesia Forest Campaigner, M Iqbal Damanik assessed, in addition to climate change factors, the hydrometeorological disasters that continue to occur in Indonesia are also caused by an antigenic factor including the conversion of land functions by humans themselves. He gave an example, the flooding that hit Bekasi was caused by an area of 147,000 Bekasi river water, but only 1,700 hectares of forest. This means that the landscape has turned into an area that has been built so that water absorption is much reduced.

He revealed, ideally according to the rules, 30 percent of the watershed area must be covered by forest. Therefore, the government is required to comply with the rules regarding 30 percent of the cover on the watershed flow. This is because infrastructure development, especially housing in the watershed, has a different impact from non-watershed areas, so it must be stricter. This flood is part of an extreme weather or called a hydrometeorological disaster. So the government must immediately implement a commitment to reduce its emissions," he said.

Head of the Meteorology, Climatology and Geophysics Agency (BMKG), Dwikorita Karnawati, admitted that her party had predicted an increase in the potential for hydrometeorological disasters in 2025. One of the factors that also increased the potential for hydrometeorological disasters was sea level temperature deviations in the Pacific Ocean, Indian Ocean, and local Indonesian waters.

According to him, the temperature deviation is closely related to the La Nina phenomenon which causes an increase in rainfall in Indonesia. The weak condition of La Nina at the end of 2024 continued until early 2025. This causes Indonesian water temperatures to be warmer than the average, which in turn increases the formation of rain clouds," he added.

La Nina itself is a global climate anomaly event characterized by sea surface brightness or sea surface temperature in the central and eastern Pacific Ocean which is cooler than its normal temperature. BMKG previously estimated that weak La Nina would only last until the first quarter of 2025. Generally starting November, and expected to continue until January, February, March," explained Dwikorita.

Meanwhile, the Head of the National Disaster Management Agency (BNPB), Suharyanto explained, from the available data, his party recorded 614 disasters from January to March 10, 2024, where the majority of these disasters were wet hydrometeorological disasters. Moreover, entering March-April 2025, Indonesia is experiencing extreme weather. Therefore, efforts and mitigation measures are needed to be prepared in dealing with hydrometeorological disasters, especially for areas prone to hydrometeorological disasters," he said.