A researcher at the Climate and Atmosphere Center at the National Research and Innovation Agency (BRIN) Didi Satiadi explained the reason why the beginning of the rainy season caused immediate flooding in Jakarta and its surrounding area.
“The flooding was caused by the significantly heavy rain that occurred the day before. This could also be attributed to the runoff from Bogor,” he said on Tuesday.
According to Didi, BRIN’s research found that Java Island is experiencing a transitional period from the dry season to the rainy season. This transitional period caused the dry Australian monsoon and the wet Asian monsoon to clash and caused a fluctuating wind velocity and direction.
In this condition, he said, the weather becomes hot at noon, which accelerates the cloud formation and causes quite intense rain in the afternoon. The weather could also become so extreme that it causes lightning, hail, and tornados.
“During this transitional period, the potential for extreme weather phenomenon also rises, including strong winds that could uproot trees,” he said.
Concerning the flooding in Jakarta and Bekasi on November 5, Didi explained that at the time, there was a strong convergence of wind from the sea in the areas around Bogor. “This caused a rapid formation of cloud,” he added.
Additionally, Didi said, the flooding may be caused by several factors, such as high rain intensity, geographical conditions, river overflow, and environmental situations. “It’s harder to absorb a high volume of water debit, causing a flood,” he concluded.