A Heat Wave Happens In Indonesia And A Touch Temperature Of 40 Degrees? Check Out The Detailed Explanation Of BMKG!

Illustration - Several BMKG employees show a weather forecast chart at the BMKG Office, Jakarta (ANTARA)

JAKARTA - The Meteorology, Climatology and Geophysics Agency (BMKG) spoke up following the news about the heat wave that occurred in Indonesia. Mentioned, at this time the weather is very hot, the temperature during the day can reach 40 degrees Celsius. People are advised to avoid drinking ice or cold water.

Acting Deputy for Climatology Urip Haryoko said the news was a mere hoax. "The news circulating is certainly not correct and not true or a hoax, because the current hot and scorching temperature conditions cannot be considered a heat wave," he said in a written statement in Jakarta, Antara, Saturday, October 16.

Heat waves occur in areas located at middle and high latitudes. Meanwhile, Indonesia is located in the equatorial region where the weather dynamics system does not allow the occurrence of heat waves.

A heat wave in weather and climate science is defined as a period of unusually hot weather (temperature) that typically lasts at least five consecutive days or more (according to the World Meteorological Agency or WMO limits) accompanied by high humidity.

To be considered a heatwave, a location must record a daily maximum temperature that exceeds a statistical threshold, such as five degrees Celsius hotter than the climatological average maximum temperature, and has been for at least five consecutive days.

"If the maximum temperature occurs within the average range and does not last long, then it is not considered a heat wave," he said.

He added that heat waves generally occur in association with the development of a persistent high atmospheric pressure system weather pattern in an area for several days.

In the high pressure system, there is a movement of air from the upper atmosphere to the surface (subsidence) so that it is compressed and its temperature increases.

This center of high atmospheric pressure makes it difficult for air to flow from other areas into the area. The longer this high-pressure system develops in an area, the hotter the area becomes, and the harder it is for clouds to grow in that area.

"Heat temperatures that occur in the territory of Indonesia are a phenomenon due to the apparent motion of the Sun which is a regular cycle and occurs every year, so the potential for hot air temperatures like this can also be repeated in the same period every year," he said.

Currently, based on BMKG's monitoring of the maximum temperature in the territory of Indonesia, it is true that the highest temperature during the day has increased in the last few days. Temperatures above 36 degrees Celsius were recorded in Medan, Deli Serdang, Jatiwangi, and Semarang on meteorological records dated October 14, 2021.

The highest temperature on that day was recorded at the Center for Meteorology, Climatology and Geophysics Region I, Medan, which was 37 degrees Celsius. However, this temperature record is not a large deviation from the maximum average climatic temperature in the region, still within the range of variability in October. At least the maximum temperature that has risen in recent days could be due to several things.

In October, the apparent position of the Sun's motion is directly above the islands of Java, Bali and Nusa Tenggara on its way to 23 south latitude after leaving the equator. The apparent position of the Sun above Java Island will occur twice, namely September/October and February/March, so that the maximum temperature peak is felt in the Java to NTT region around these months.

Sunny weather also causes more optimal direct sunlight to the surface so that the surface temperature warms up. This condition is related to the presence of Tropical Cyclone Kompasu in the northern part of the South China Sea which attracts air mass and the growth of rain clouds and moves away from Indonesian territory so that the weather in the Java region tends to be cloudier in recent days.