TEMPO.CO, Jakarta - Dieng plateau in Banjarnegara, Central Java since Friday, July 6, was covered by frost similar to snow. The frost is locally known as bun upas phenomenon which commonly occurs every year at the peak of the dry season in July-August.

“When bun upas occurred yesterday (Friday), we’ve checked that the lowest temperature was at 2 Celcius degree and this is the standard temperature,” said Dieng Kulon Village secretary Sabar Alfarisdi in a phone call with Tempo on Saturday, July 7.

Sabar explained the extreme temperature that had been felt by the residents during the bun upas phenomenon reached minus five degrees Celcius, as in three years ago. “This morning's temperature is 5 degrees Celcius but in the afternoon it usually rises to 16-25 degree,” he said.

Bun upas phenomenon is marked by steams emitted from the land. The lowest temperature felt by the residents usually at around 4 to 5:30 am.

Three areas in Dieng Kulon village were most affected by the phenomenon, namely around Arjuna temple, Dwarawati temple, and Setyaki temple. “Some 90 hectares of potato farms are frozen due to bun upas,” Sabar added.

The phenomenon of Dieng's bun upas or in local language means toxic dew is not harmful to humans but the agricultural plants, especially which are entering its harvest period. “50 percent of 90 hectares of potato farms are ready to be harvested but it is prone to death because of bun upas,” Sabar said.

PRIBADI WICAKSONO