The phenomenon occurred when the sunlight was scattered up in the air by micro particle with diameter 0.7 micrometers that called aerosol, or about the same with sun visible-light length.
According to the data compiled by BMKG, concentration of pollutant particles sized less than 10 micrometers was very high in surrounding area of Jambi, Palembang, and Pekanbaru.
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Yet the red sky only appeared in Jambi, which indicates that the air pollutant is dominated by the 0.7 micrometers particles with high concentration.
A report by the wildfire control post of the Ministry of Environment and Forestry (KLHK) on Saturday (Sept 21) at 6.00 pm, showed that 56 hot spots were detected by satellite image of Terra Aqua (NASA), with the level of trust over 80 percent.
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At the same day, Director of Land and Forest Fire KLHK Raffles Brotestes Panjaitan stated that Central Kalimantan Province government had declared emergency status during September 17 to 30, 2019.
The six other provinces exposed by haze caused by wildfire, namely Jambi, Riau, South Sumatera, West Kalimantan, Central Kalimantan, and South Kalimantan, also set emergency status that are due in various date, such as October 20 and 30, 2019.
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