TEMPO.CO, Jakarta - A researcher from the National Research and Innovation Agency (BRIN) on Sunday revealed the flooding abnormality in Java Island’s northern coastal regions such as North Jakarta, Indramayu, Tangerang, Bekasi, and the Thousand Islands compared to previous cases.

The BRIN climatology Center for Atmospheric Research and Technology researcher Erma Yulihastin noted that the annual floods inundating these regions were not the common moon tides.

“They are not just caused by the common moon tides but also due to the number of storm surges,” said Yulhastin on December 5. "This storm was generated by three meso-scale vortex disturbances that are currently forming in Indonesian territory.”

A storm surge, storm flood, tidal surge, or storm tide is a coastal flood or tsunami-like phenomenon of rising water commonly associated with low-pressure weather systems, such as cyclones.

This makes Indonesia’s weather condition be heavily controlled by vortex storms which in turn sparks extreme weather in Kalimantan’s northern sector and the southern sectors of Java, Madura, Bali, Lombok, and West Nusa Tenggara.

The direct effects of the vortex cause high intensity rainfall accompanied by strong winds or storms in the aforementioned regions and can potentially spread to Northern Java’s mainlands and coastlines. This in turn, increases storm surges and potentially sparks coastal flooding in Java’s northern coast.

Read: Central Kalimantan Declares Emergency Response Status in Kapuas Flooding

ANWAR SISWADI (CONTRIBUTOR)