Rainfall Intensity Remains High

KOMPAS/JUMARTO YULIANUS

A forecaster of the Meteorology, Climatology and Geophysics Agency (BMKG) looks at a weather satellite image of Indonesia on Tuesday (19/12) at the Meteorology Operations Room in Jakarta. A BMKG analysis shows the high probability of heavy rains, strong winds and high tides in Indonesia ahead of the Christmas and New Year’s holidays.

JAKARTA, KOMPAS -- Rainfall intensity is expected to drop in Sumatra in the next three days. However, it will increase in central and eastern Indonesia. People have been urged to watch out for floods and landslides.

Heavy rain poured over several regions in Indonesia, leading to fatal floods and landslides. These hydrometeorological disasters are expected to continue throughout February because of the continuously high intensity of rainfall.

Meteorology, Climatology and Geophysics Agency (BMKG) data shows varying atmospheric conditions in several regions in Indonesia. The insignificant mass of cool water flows from Asia and atmospheric subsidence due to the Madden Julian Oscillation (MJO) put pressure on cloud development and reduced rainfall intensity in western Indonesia.

The phenomenon means decreasing rainfall intensity in several regions in Sumatra in the next three days. The center of low air pressure over Australia’s Carpentaria Bay has significantly affected increasing rainfall intensity in the region.

“There are several wind convergence zones between Central Java and East Nusa Tenggara that will increase rainfall intensity in the region in the next several days. Parts of Kalimantan, Sulawesi, Maluku and Papua are also affected by the center of low air pressure,” BMKG weather forecast division head Agie Wandala Putra said on Friday (1/2/2019).

15-hour rain

The rain that lasted for 15 hours in Manado, North Sulawesi, from Thursday (31/1) night to mid-Friday led to floods and landslides. Three died, more than a dozen were injured and 5,000 in three districts fled their homes.

Landslides occurred in Mahawu, Tuminting district, and Tikalabaru subdistrict in Tilaka district on Friday at around 9 a.m. Central Indonesian Time. The disasters killed two and severely damaged several homes. Ten districts were flooded, with Tuminting, Kombos and Bunaken Daratan being the worst hit regions. In several regions, inundation was 1 meter deep.

North Sulawesi Disaster Mitigation Agency (BPBD) head Joi Oroh said heavy rain over a long period of time resulted in the Tondano and Bailang rivers to overflow. Water in several locations subsided only after rain stopped at 3 p.m. At around 4 p.m., it rained again for half an hour.

Agie said that the flooding in Manado was caused by rainclouds formed by the shearline. “Water vapor in Manado was high enough to support cloud development and rain in the past few days,” Agie said.

On Friday, North Sulawesi Governor Olly Dondokambey visited the disaster-affected site in Bailang, Bunaken Daratan; Sumompo, Tuminting; and Kombos district. He urged his staff to be on alert in providing help for affected locals.

Triggering landslide

In West Kalimantan, heavy rain led to a landslide at Medeng and Sungkung II villages in Siding district, Bengkayang regency, on Thursday at 9:30 p.m. Three died, two were missing and 11 homes were buried.

“The landslide occurred on Thursday at 9:30 p.m. The areas are remote. People in Sungkung II live on a slope, which is prone to landslides when it rains. Of the three dead bodies, one has been found and two are still missing,” Bengkayang regency BPBD head Yosef said.

Apart from fatalities, the landslide also damaged 11 homes. Nine are severely damaged and another two are buried. Locals whose homes are buried now live either in their relatives’ homes or at a local church.

“For now, locals are still searching for buried victims with whatever tools they have. The digging process is very limited by the lack of heavy equipment,” Yosef said. Sungkung is a remote region that borders Malaysia.

West Kalimantan BPBD head TTA Nyarong said locals in the village live on a slope. Bengkayang is listed as a region with moderate to high soil movement potential, along with Kapuas Hulu, Ketapang, Landak, Mempawah, Sambas and Sintang regencies.

Heavy rains on Thursday and Friday also led to floods in Surabaya. A child slipped into a gutter after water overflowed onto the streets and died.

Surabaya Bina Marga road agency head Erna Purnawati said the floods were caused by gutters’ inadequate capacity, which led to inundations.

National Disaster Mitigation Agency (BNPB) spokesperson Sutopo Purwo Nugroho said in Surabaya that BNPB data showed that January and February were usually the peak of flooding, landslides and tornados. In January this year alone, there were 366 disasters with 94 people either dead or missing, 149 injured, 88,613 fleeing from their homes, 4,013 houses damaged and 146 public facilities damaged. More than 98 percent of these disasters are hydrometeorological.

Compared to last year, the frequency and fatalities of disasters in January this year was higher. Disaster frequency increased by 57.1 percent this January, with the number of deaths and missing people increasing by 308.7 percent and the number of injured people by 186.5 percent. However, the number of people who fled their homes or are affected decreased 49.8 percent and the number of damaged homes decreased 59.7 percent. (AIK/ESA/ZAL/SYA/ETA/TAN/E22)