September 2023's Scorching Heat: Fourth Highest Temperature Anomaly Since 1981

The Meteorology, Climatology, and Geophysics Agency (BMKG) reported that the average air temperature in September 2023 reached 27 degrees Celsius. This average was obtained from an analysis of 116 BMKG observation stations.

BMKG stated that the climatological normal air temperature for September 2023, compared to the 1991-2020 period in Indonesia, was 26.6 degrees Celsius, still within the normal range of 20.1-28.6 degrees Celsius.

The difference between the average air temperature in September 2023 and August 2023 generally shows a temperature increase or a positive value. This was measured from 148 BMKG observation stations in Indonesia.

BMKG explained that the largest temperature increase was recorded at Sultan Hasanuddin Meteorology Station, Makassar, reaching 1.3 degrees Celsius. Meanwhile, the largest temperature decrease was recorded at Ranai Meteorology Station, Natuna, reaching -1.1 degrees Celsius.

From these calculations, the average air temperature anomaly in September 2023 showed a positive anomaly with a value of 0.4 degrees Celsius. BMKG considers this anomaly quite high.

"The Indonesian air temperature anomaly in September 2023 is the fourth highest anomaly throughout the observation period since 1981," wrote BMKG on its official website, quoted on Tuesday (3/10/2023).

BMKG added that, in general, the average air temperature anomaly per station in September 2023 showed a positive anomaly or higher than its climatological average.

The highest anomaly was recorded at Pangsuma Meteorology Station, Kapuas Hulu, reaching 2 degrees Celsius. While the lowest anomaly was recorded at Karel Sadsuitubun Meteorology Station, Southeast Maluku, at -0.6 degrees Celsius.

Meanwhile, the highest anomaly throughout September 1981-September 2023 was recorded in September 2022, which soared to 0.8 degrees Celsius. The average temperature reached 27.30 degrees Celsius.

Citing the National Centers for Environmental Information (NCEI) website from the United States, temperature anomalies are very important to highlight. A positive anomaly indicates that the observed temperature is warmer than the baseline temperature. While a negative anomaly indicates that the observed temperature is colder than its baseline temperature.

NCEI explains the difference between calculating the average temperature and the anomaly. When calculating the absolute average temperature, monitoring the location of the station or altitude will affect the resulting data. For example, higher areas tend to be colder than lower ones, and urban areas tend to be warmer than rural areas.

However, NCEI argues that when calculating temperature anomalies, these factors are less important.

"For example, during a summer month in a region, it might be colder than average both on a mountaintop and in a nearby valley, yet the absolute temperatures would be very different at the two locations," wrote NCEI on its official website, quoted Tuesday (3/10/2023).

(Also read: [Natural Disasters Related to Climate Change are Increasing on a Global Scale])