Last weekend, skies over an Indonesian province turned red due to the widespread forest fires which have plagued vast parts of the country. A resident in Jambi province, who captured startling pictures of the red sky, said the haze “hurt her eyes and throat”.
Every year, fires cover Indonesia in a smoky haze that literally blankets the entire South East Asian region. A meteorology expert told the BBC that the unusually red sky was caused by a phenomenon called Rayleigh scattering.
Eka Wulandari, living in the Mekar Sari village in Jambi province, captured the blood-red skies in a series of photos taken midafternoon on Saturday.
According to her, the haze conditions had been especially “thick that [day]”. The 21-year-old uploaded the pictures on Facebook that have since been shared more than 34,000 times.
She told BBC Indonesian that many people online had originally doubted whether or not the photos were real.
She said, adding that haze conditions remained severe on Monday, “But it’s true. [It’s a] real photo and video that I took with my phone”.
Another Twitter user Zuni Shofi Yatun Nisa posted a video showing similarly colored skies.
Ini sore bukan malam. Ini bumi bukan planet mars. Ini jambi bukan di luar angkasa. Ini kami yang bernafas dengan paru-paru, bukannya dengan insang. Kami ini manusia butuh udara yang bersih, bukan penuh asap.
Lokasi : Kumpeh, Muaro Jambi #KabutAsap #KebakaranHutanMakinMenggila pic.twitter.com/ZwGMVhItwi
— Zuni Shofi Yatun Nisa (@zunishofiyn) September 21, 2019
She said, “This is not Mars. This is Jambi. We humans need clean air, not smoke.”
BMKG Indonesia meteorological agency said satellite imagery exposed numerous hot spots and “thick smoke distribution” in the area around the Jambi region.
Associate Professor Koh Tieh Yong, of the Singapore University of Social Sciences, explained that this phenomenon named Rayleigh scattering occurs with certain types of particles that are present during a period of haze.
He told the BBC, “In the smoke haze, the most abundant particles are around 1 micrometre in size, but these particles do not change the colour of the light we see. There are also smaller particles, around 0.05 micrometres or less, that don’t make up a lot of the haze but are still somewhat more abundant during a haze period [than a normal non-haze period]… but this is enough to give an extra tendency to scatter red light more in the forward and backward directions than blue light – and that is why would you see more red than blue.”
He said that the fact the photos were taken about noon could have caused the sky to seem redder.
Prof Koh added that this phenomenon would not “modify the air temperature” and said, “If the sun is overhead and you look up, [you will be looking] in the line of the sun, so it would appear that more of the sky is red.”
In Indonesia, this year’s haze levels have been some of the worst in years which is caused by open burning and to some extent, parts of Malaysia. Such burning usually peaks from July to October during Indonesia’s dry season. Indonesia’s national disaster agency reports that nearly 328,724 hectares of land had already been burnt in the first eight months of 2019.
Partial blame for the haze lies with big corporations and small-scale farmers who take advantage of the dry conditions to clear vegetation for palm oil, pulp, and paper plantations by employing the slash-and-burn method. This technique is used by many in the region as it is arguably the easiest way for farmers to clear their land and also helps them get rid of any disease that may have affected their crops.
Unfortunately, these fires often surge out of control and spread into protected forested areas. Although slash-and-burn is illegal in Indonesia, it has been allowed to continue for years due to alleged corruption and weak governance.