24-Hour Weather Modification to Prevent Heavy Rain in Greater Jakarta

KOMPAS/RONY ARIYANTO NUGROHO

A resident is seen amid damages in the village of Urug, Sukajaya district, Bogor regency, West Java, due to landslides and flash floods, on Wednesday (8/1/2020). Access to this area was still cut-off, making it difficult to distribute aid. Authorities are still struggling to to open up access roads to a number of villages.

JAKARTA, KOMPAS - Rains of moderate to heavy intensity are forecast to occur over the weekend. Although the rainfall is not expected to be as intense as earlier, the risk of flooding is quite high because it coincides with the expected rise in sea tide on Jan. 9-12.

In anticipation, the Weather Modification Technology Team (TMC) of the Agency for the Assessment and Application of Technology (BPPT) will collaborate with the National Disaster Mitigation Agency (BNPB), the Air Force and the Meteorology, Climatology and Geophysics Agency (BMKG) to conduct TMC operations 24 hours a day.

The head of the TMPT BPPT Central Office Tri Handoko Seto in Jakarta, Wednesday (8/1/2020), said the TMC operation aimed at reducing the potential for heavy rains to prevent flooding in Greater Jakarta has been carried out since Jan. 3. The operation is carried out to bring down a cloud that has the potential to cause rain outside Greater Jakarta or before it enters the area.

Rain occurred in the seeding area above the Sunda Strait and the Thousand Islands.

As a result, there have been no heavy rains since Dec. 31, 2019 and Jan. 1. Weather modification is claimed to have succeeded in reducing the intensity of moderate to heavy rains that should have arrived in Greater Jakarta on Monday.

Based on the data, the increase in cloud concentration in the western part of Greater Jakarta has the potential to cause rains. Therefore, cloud seeding was carried out in the western and northern regions of Greater Jakarta.

"Rain occurred in the seeding area above the Sunda Strait and the Thousand Islands," said BPPT chief Hammam Riza some time ago. Rain also fell in the eastern waters of Lampung and Jakarta Bay.

KOMPAS/RONY ARIYANTO NUGROHO

Spots of landslide are seen on the hills in Sukajaya district, Bogor regency, West Java, Wednesday (8/1/2020). Authorities are still struggling to to open up access roads to a number of villages.

Potential rain

Responding to weather warnings delivered by the US Embassy in Jakarta, on Monday (6/1) that there would be heavy rains on Jan. 12, the head of BMKG’s meteorology center for public, Fachri Radjab, said in general, rains of heavy intensity could still potentially to occur this week.

Looking at its potential, from Jan. 9-10, there will be heavy rains, with higher intensity than that expected on Jan.12, " he said. "Regarding the early warning of the US Embassy, we do not know where their data is coming from," he added.

BMKG analysis shows, on Jan, 9-10, the potential for moderate to heavy rainfall accompanied by strong winds and lightning could occur from early morning, especially in North Jakarta, Central Jakarta, West Jakarta, East Jakarta, South Jakarta, Tangerang, Bekasi, part of Depok, and Bogor.

Looking at its potential, from Jan. 9-10, there will be heavy rains.

The rain intensity can decrease in the morning but it has the potential to increase again in the late afternoon. As for Jan. 11-12, the rain in Greater Jakarta is expected to decline.

Rain of mild to moderate intensity could still occur, especially in Bogor, Depok, South Jakarta, East Jakarta, Bekasi and Tangerang.

The BPPT’s TMC team predicts heavy rain on Sunday (12/1) in Greater Jakarta. The average rainfall is estimated at 50-100 millimeters per day. This rain is not as heavy as that on Dec.31 2019 and Jan.1.

“Heavy rains still have the potential to cause inundation at a number of locations, "said Tri Handoko.

KOMPAS/RIZA FATHONI

Crew of the CN 295 aircraft from Air Force Squadron 2, piloted by Capt. Gilang and copilot Sc. Lt. Kukuh which took off from Halim Perdanakusumah Air Base, scatter salt during the Weather Modification Operation (TMC) in the sky of Sunda Strait area, on Friday (3/1/2020).

High tide

Although the intensity of rain is not expected to be as high as that at the turn of the new year, the threat of flooding is increasing due to the expected increase in tides in Jakarta Bay on Jan. 9-12.

According to the deputy of BMKG for meteorology, R. Mulyono R. Prabowo, the tide could reach 0.6 meters and could hamper the flow of river water into Jakarta Bay.

The head of the Information and Communication Center of the BNPB, Agus Wibowo, called on people not to panic in responding to weather warnings from the US Embassy.” However, we still need to be vigilant," he said.

Agus said weather modification would continue to avoid heavy rains in Greater Jakarta.