Twelve orangutans and 19 staff were evacuated by boat from the Sebangau Forest Refuge in Central Kalimantan on Monday after fire cut the access track. The rescue drew attention to a graver finding from the same peat-swamp region: researchers say monitoring data show that a 380,000-hectare area has shifted from storing carbon to releasing it.
The claim, made by a Singapore-based research team on Wednesday, is among the clearest signs yet of a local peatland tipping point. The team says the shift could speed up as dry peat burns and releases carbon, making the ground still warmer and drier. It estimates that without urgent water-management measures, emissions from the wider affected area could reach 150 million tonnes by 2040.
A peat dome running dry
Researchers with the Meridian Peat Observatory analysed readings from nine towers and water-level sensors across the Sebangau peat dome. Seven towers recorded a net carbon release over the 12 months to September. Across 22 consecutive months, the average water table sat 41 centimetres (16 inches) below the peat surface — low enough, the team says, to leave the upper layer exposed to drying and fire.
“This is not simply one bad fire season. The peat has stayed dry long enough for the whole system to change state,” said Trishana Chia-Prabhu, a peat-carbon scientist based in Singapore. “If the water table keeps falling, fires become easier to start, and the carbon loss makes the next dry spell more dangerous.”
The researchers estimate that 640,000 hectares (1.58 million acres) of connected peatland could face the same shift by 2030 if drainage channels remain open and dry seasons deepen. In the worst-case projection, repeated fires and peat decay would release 150 million tonnes of carbon dioxide by 2040. The team says its forecast is a regional scenario, not a prediction that all Borneo’s rainforest will burn.
Reassurance meets the data
A provincial environment official, Luana Casanova, said the fire was contained before it reached the refuge and that recent rainfall had helped lower immediate danger. “The reserve remains protected, and we are not declaring an irreversible regional collapse,” she said. She said crews were checking canals and firebreaks ahead of the next dry season.
Ayinde Olubunmi, a hydrologist who reviewed the team’s results, said the official account did not answer the central concern. Rain can damp surface vegetation without restoring water deep in the peat, he said; in the monitoring area, several sensors stayed below the team’s 40-centimetre threshold even after rain. “You cannot call the system safe because the top looks wet,” he said.
The refuge rescue showed how quickly conditions can squeeze people and wildlife into a narrow window for action. Staff moved the orangutans by boat before smoke and fire blocked the only road. No one was injured, and the animals were taken to a separate holding site, refuge managers said.
Scientists are urging authorities to block drainage canals, restore water levels and halt new peatland drainage before the 2027 dry season. The team estimates that emergency canal works and monitoring would cost far less than repeated fire response, but it has not yet published a full cost plan. For Singapore, roughly 1,050 km (650 miles) from the study area, a larger fire season could also mean more haze days; researchers stress that smoke levels depend on wind and rainfall.
The scientists caution that a single season cannot establish a permanent shift across an entire forest region. But their measurements, the fire and the hurried evacuation point to a narrow chance to act, said Chia-Prabhu: “We have evidence that the peat is changing now. Waiting for a perfect forecast means waiting until the next fire has done the measuring for us.”
