When ecologist Eric Meijaard first trekked through the peatlands of Indonesia in 1997, it was awful, dense and very wet.
Said Dr Meijaard, 48: "It wasn't pleasant at all. We were sometimes up to our necks in water because peatlands are extremely waterlogged. "But now that many of the peatlands have been drained, it's probably so different."
Dr Meijaard, who is an Indonesia-based associate professor at the University of Queensland in Australia, called this year's haze the biggest environmental crime of the 21st century.
In a recent article for the Jakarta Globe, he said he considered it a crime, and not just a disaster, because endangering the lives of millions of people, destroying protected forests and their wildlife, and threatening the global environment are all criminal acts.
Speaking to The New Paper (TNP) over the phone, Dr Meijaard said: "The (Indonesian) government has been sitting on this problem for almost 20 years. It's time for them to recognise that enough is enough.
"All these fires could have been prevented by solid policies, land-use planning, and law enforcement. None of these were enacted and now people all over the world are suffering the consequences."
Dr Meijaard also said the Indonesian government and companies involved in haze-causing fires need to understand the costs of developing the peatlands.
He said: "They can't just look at the benefits (of development). There are severe costs, such as loss of biodiversity, increased flooding and also droughts. These can translate into tangible costs as well."
Heavy rains across South-east Asia have helped put out at least 50 hotspots in Sumatra, according to Bloomberg, quoting a spokesman at Indonesia's disaster management agency.
But the annual haze problem is far from over.
Experts have also warned that this year's haze situation could be one of the worst to blanket regions in South-east Asia, surpassing similar crises in 1997 and 2013.
While conventional aerial water bombing might put out surface fires, smouldering fires can still burn up to 2m to 3m beneath the surface of the peatlands because water tables will drop two to three times lower during the dry period, said Dr Desmond Lee Wan Aik, 40, a senior engineer with international water consulting and research firm DHI Water & Environment.
"It's like burning a stack of papers that is 3m thick. You can put out the fire on top, but there is still smouldering heat beneath the piles of paper," said Dr Lee, who is a hydrologist by training.
For his post-doctoral research, Dr Lee spent three years studying Indonesia's peatlands in Jambi, a region in Central Sumatra, which is one of the worst haze-shrouded regions this year.
He said that smouldering fires can be doused only by heavy downpours and by building dams to raise the water table levels. But the best solution to the haze and peatlands fires is a political one.
Dr Lee said: "The situation can't be solved unless the Indonesian government makes a strong commitment towards land and people management to deal with peatland development."
Added Dr Lee: "The annual haze is partly due to the dry season and the common practice of draining and burning peatlands for land development or agriculture.
"But this time, it is further exacerbated because of the El Nino weather pattern."
Dr Louis Verchot, a research director of Forests and Environment at the Centre for International Forestry Research based in Bogor, Indonesia, said that development activities in Indonesia have been ongoing more rapidly than before, so there are vast areas of drained peatland that have been feeding the infernos.
The Straits Times reported that the haze crisis could cost the country up to 475 trillion rupiah (S$48 billion).
The haze-related death toll has also risen to 19.
Ms Hafizhah Jamel, 32, co-founder of mask-collection initiative Let's Help Kalimantan, visited the burning peatland forests of Kalimantan in October.
Her group collected more than 17,000 N95 masks for locals there who experienced PSI levels of close to 2,000.
Ms Hafizhah, who works in the education industry, said: "The smell of the burning (peatlands) is bad, it's worse than barbecue smoke. It also smells like something is rotting."
"The conditions were so bad that my friends and I were actually looking forward to returning to Singapore, where the PSI 200 levels were nothing compared with what the people were facing over there."
Challenges of putting out peatland fires
The fire beneath can resurface.
Sometimes, the smouldering underground fires can flare up again and continue to burn and contribute to the haze.
WHAT ARE PEATLANDS
Peatlands are made up of decomposed forest debris, decayed vegetation and organic matter. They are formed over thousands of years and are home to many plants and animals, including endangered species like the orangutan.
The dried-out peat ignites easily and the fires burn on the surface and up to almost 3m underground. The smoke from the flames and the smouldering fire is what causes the haze.
Peatlands are naturally waterlogged. But they become dry after being drained by canals that are dug by people seeking to clear and burn the land for development and agriculture. The El Nino weather pattern, which has delayed the rainy season, also means that the peatlands are drier than usual this year.
The peat can reach 20m (about seven storeys) in depth.
Water table is the level below which the ground is saturated with water. During dry season, the water table can drop to create a larger column of dry peat, which is highly combustible.
This article was first published on Nov 2, 2015.
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