This is a computer simulation of the 2019 haze episode, based on satellite observations.
A major source of the haze comes from the burning of peatlands in Indonesia, which are extra flammable once they are dried out for agriculture.
Climate patterns such as El Nino, which brings about drier weather, allow smoke from the burning peatlands to build up in the air.
How far the smoke travels depends on factors such as wind direction and intensity.
This can determine whether the haze reaches neighbouring countries including Singapore, such as in 2019.
The haze is back in Singapore, with the air quality index reaching unhealthy levels in some parts of the city.
The 24-hour Pollutant Standards Index (PSI) readings entered the unhealthy range on Oct 7, with the highest reading recorded in the east.
In a statement on Oct 6, NEA said that it will start providing daily haze advisories from Oct 7 evening after the number of hot spots in Sumatra more than tripled in one day.
Earlier this year, researchers from the Singapore Institute of International Affairs - a local think-tank that releases a Haze Outlook report every year - predicted a high risk of severe transboundary haze in Indonesia, Malaysia, Singapore and the surrounding region.
The haze intensity we see is largely linked to climate patterns such as El Nino - a naturally occurring phenomenon associated with the warming of surface waters in the Pacific Ocean - and is set to bring hotter and drier weather to South-east Asia and Australia.
This is coupled with the possibility of another climate phenomenon, a positive Indian Ocean Dipole (IOD), which causes warmer sea surface temperatures in the western Indian Ocean.
Due to the possibility of these two phenomena happening at the same time, it is likely that there will be some degree of transboundary haze in Indonesia, Malaysia, Singapore and the surrounding region, according to the report.
In general, hotter conditions make it more prone for peatlands to burn, explains Dr Santo V. Salinas, an atmospheric scientist at the Centre for Remote Imaging, Sensing and Processing at National University of Singapore (NUS-Crisp). The question is then how intense will El Nino be. “A strong El Nino for example, means a longer dry period in South-east Asia, which means there is much more time to keep burning,” adds Dr Santo.
The National Oceanic and Atmospheric Administration, which focuses on climate research and weather predictions in the US, announced that the odds of El Nino becoming a moderate event is about 84 per cent. There is a 56 per cent chance of it being a strong event.
If there is a really strong El Nino and a really strong IOD, then we will expect to see worse haze conditions.who worked on the annual Haze Outlook report
The last time both climate phenomena coincided was in 1997, when Singapore’s 24-hour PSI hit an all-time high of 226 on Sept 18, 1997, he adds. The economic cost of the haze that year, which coincided with the Asian financial crisis, was estimated at US$300 million.
However, there is a silver lining. Even if a strong El Nino and positive IOD do occur, it is likely that the haze will not be as severe compared with the incidents seen in 1997 and 2015, according to the report. This is due to the sustainability commitments Indonesia and other Asean countries have in place to prevent fires and avoid deforestation. In fact, as at 2022, Indonesia’s deforestation rate was the lowest in 20 years.
We haven’t experienced the haze since 2019. So why did it disappear, and why is it back only now?
The opposite of El Nino is La Nina, which results in cooler temperatures and wetter conditions. The past couple of years were in La Nina season, which explains why we haven’t seen the haze since 2019, says Mr Chia Aik Song, research scientist from NUS-Crisp.
It could also be due to the slowdown in economic activity because of Covid-19, says Associate Professor Helena Varkkey from the Department of International and Strategic Studies at Universiti Malaya. Fires are more prone to occur on sensitive landscapes such as peatlands - which is soil composed of partially decayed organic matter - when there is activity on the ground. But Covid-19 reduced the number and frequency of people going into the forests and disrupting the landscape.
“It's about landscapes being disturbed, being drained, being allowed to dry out when they’re supposed to be more moist,” says Dr Varkkey whose areas of expertise include transboundary haze governance in South-east Asia and global palm oil politics. “So when you don't have people going into the forest, when you don't have activity in the area, the landscape is more stable.”
One factor that could impact the severity of haze is the location of the hot spot. We analysed wind and fire data of previous years and found a pattern: Shifting hot spots
In 2013, when Singapore experienced its highest PSI level recorded on June 24, the hot spots were mostly in Riau, the closest Indonesian province to Singapore.
Upon adding on a layer of wind data, we could see that it was directly shrouding the island.
In 2015, however, most of the fires were in South Sumatra…
and then it shifted to Kalimantan in 2019.
There were still fires in South Sumatra but fewer than in 2015. This was also one of the factors why Singapore wasn’t as badly impacted by the haze in 2019 compared with neighboring countries, says Dr Santo.
This pattern of shifting hot spots could be linked to where palm oil plantations were opening up. “Maybe some regions had the boom time at different peaks, at different times,” says Dr Varkkey. “Riau was a bit earlier, then it was Kalimantan. And now we have Papua coming up as sort of a big area for plantations.”
Some experts also say it could be impacted by the demand and prices of commodities such as palm oil.
Indonesia and Malaysia together make up 84 per cent of palm oil production. In the latest Haze Outlook report, researchers say there is some concern that the current elevated prices might increase the risk of deforestation and, therefore, the risk of haze.
The increased market prices could be an incentive for companies to produce more palm oil, resulting in more land clearing to make way for crops to feed the growing demand. The prices of palm oil have been on the rise since the start of Covid-19 and spiked further in 2022 due to the Russia-Ukraine war.
So who is burning the peatlands? The situation isn’t black and white, says Dr Varkkey. In fact, it is no longer common practice for companies to use burning to make way for crop plantations.
In Indonesia, land is designated to companies or individuals for specific purposes such as agriculture, mining and forestry. These plots are called concession areas and are typically regulated by the Indonesian government through permits and licences.
The 2013 haze event drew international criticism from neighbouring countries on Indonesia’s land-clearing practices and concession areas, which prompted its government to take more proactive measures to address deforestation, peatland management and fire prevention.
One such example is making the provisional moratorium on forest clearance permanent. The moratorium, which was introduced in 2011, aimed to halt the conversion of primary natural forests and peatlands into other land uses.
Deforestation rates drop to lowest in 20 years
Fires are not intentionally started by humans nowadays, explains Dr Varkkey. “A lot of people are watching concessions very closely,” she adds. “But the very fact that these concession areas are present on these very sensitive landscapes makes the fire risk higher.”
Hence, it is more of how the land is being managed and the activity around it that makes it more prone to wildfires.
Let’s take a look at where peatlands and concession areas overlap.
These are the concession areas in Indonesia. Concession areas are places where palm oil companies are allowed to operate and grow crops.
For peatlands to be used as plantations, they first need to be dried out. Ideally, peatlands shouldn’t be within concession areas as they can catch fire easily.
However, over 12.9% of the concession areas are on peatlands. These overlapping areas are even more prone to being burned when there are accidental fires or short dry spells.
Here are the fires in Indonesia in May 2023. Even though most fires are outside of concession areas, they can be linked to activities within them.
Once you dry out one part of a peatland, the other parts will also be affected.
associate professor of environmental politics at the Department of International and Strategic Studies, Universiti Malaya
So the peatlands that are not within the concession areas are in turn affected too, says Dr Varkkey. “This is why there are a lot of fires that happen adjacent to concession areas.”
But not all hope is lost. The Indonesian government and volunteers have been implementing policies and working to manage wildfires.
The Roundtable on Sustainable Palm Oil is a non-profit organisation focused on implementing global standards for the production and sourcing of viable palm oil. There are certain fire prevention methods and standard practices or guidelines for palm oil companies to adhere to.
Earlier in 2023, Indonesian President Joko Widodo told a meeting of law enforcement officials that police chiefs would be removed from their posts if they do not do enough to handle fires in their areas — a promise that he first made in 2016 and has carried out before. Indonesia’s Environment and Forestry Minister Siti Nurbaya Bakar has also made similar comments about taking action against any companies caught starting fires.
According to Mr Choo, who worked on the report, the central government and provincial-level Indonesian officials have sent strong signals about their commitment to fire and haze prevention. He adds that the upcoming Indonesian elections in 2024 would be a push factor for officials to ensure they prevent any incidents while politicians are on the campaign trail.
“They wouldn’t want an embarrassing situation,” he says.
