BRIN’s Climate and Atmosphere Research Center indicates that 65.8 percent of the northern coast, known as Pantura, eroded between 2000 and 2024.
This loss significantly outpaces land accretion, which stands at only 34.2 percent according to the latest agency data.
BRIN scientist Tubagus Solihuddin noted on Tuesday that the region’s geological composition, primarily unconsolidated sediment, makes the shoreline highly susceptible to compression and washing away.
"The northern coast of Java is facing a real crisis. The challenges are not just erosion and flooding, but also rising sea levels and land subsidence," Solihuddin said.
The erosion is driven largely by anthropogenic factors as massive urban expansion and resource extraction have led to the modification of upstream river systems.
Activities such as dam construction and river diversion have severed the essential flow of sediment to the coast, leaving the shoreline unable to naturally replenish itself.
The environmental decay has already produced devastating results across several regencies.
In Muara Gembong, Bekasi, the sea has surged four kilometers inland, permanently submerging public infrastructure and 1,000 hectares of aquaculture ponds.
Similarly, in Demak, seawater has reclaimed up to six kilometers of territory, swallowing vital rice fields and residential areas that were historically dry land.
This situation is compounded by the dual threat of rising sea levels and sinking land.
Altimetry data reveals that the sea level in the region is rising by an average of 0.42 centimeters annually, totaling a 15.5-centimeter increase over the last 32 years.
When paired with rapid land subsidence caused by groundwater extraction, the coastal vulnerability reaches critical levels.
Solihuddin emphasized that the degradation of the northern coast is a national security issue rather than a local concern, given that the region serves as the primary backbone of the Indonesian economy.
He called for an immediate transition toward research-based, cross-sectoral policies, stressing that there is no single solution to stabilize the various unique coastal environments across the island.
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Translator: Sean Filo Muhamad, Aditya Eko Sigit Wicaksono
Editor: Arie Novarina
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