In September 2026, the smoke came back. Pekanbaru disappeared into a grey haze. Kuala Lumpur, Kuching and Singapore regularly ranked among the most polluted major cities in the world. Schools across Borneo and Sumatra moved classes online, and Indonesia recorded more than 170,000 cases of respiratory illness.

None of this was new. Anyone who lived through 1997 or 2015 has seen it before. That is the most important thing to understand about Indonesia's haze: it is not a freak event. It is a cycle, and a cycle can be broken.

A predictable cycle

The major fire and haze crises of 1997, 2015 and 2026 share the same ingredients: a long dry season, often intensified by El Niño, and large areas of peatland that have been drained for agriculture.

Each time, the pattern repeats. Fires start or spread on dry land. They reach drained peat, where they are hard to detect and even harder to put out. Smoke builds up over weeks and drifts across borders. When the rains finally return, attention moves on, until the next dry year.

Because the conditions are known in advance, the haze is, in large part, predictable. The problem is that preparation too often starts after the smoke appears.

The bill arrives every time

Haze is often described as an environmental issue. It is also one of the most expensive recurring disasters in the region.

According to the World Bank, the 2015 fires cost Indonesia at least US$16.1 billion, equivalent to 1.9% of the country's GDP that year. That is more than twice the reconstruction cost following the 2004 Aceh tsunami. According to government figures cited in the same analysis, 2.6 million hectares of land burned. The World Bank also noted that regional and global costs push the true figure higher.

Behind the economic figures are people:

• Health: prolonged exposure to smoke drives respiratory illness, as the 2026 case numbers show.
• Education: school closures and remote learning interrupt children's education, often for weeks.
• Livelihoods: farmers, workers and small businesses lose income when fields burn, factories slow down and customers stay home.
• Mobility: poor visibility cancels flights and disrupts transport.

The real cost of haze is not only what the economy loses, but what people have to live through.

The root cause is under the surface

Peat is waterlogged plant material that has built up over thousands of years. As long as it stays wet, it is remarkably stable.

The trouble starts when peat is drained. Deep canals lower the water table so that crops can grow. The upper layers dry out, shrink and gradually sink. Dry peat is fuel: once a fire reaches it, it can smoulder underground, out of sight, and flare up again long after the surface looks clear.

This is why haze keeps returning to the same landscapes. As long as peat stays drained, every major dry season carries the risk of another emergency. For businesses, it also means something uncomfortable: companies that drain peatland are, in effect, putting their own land assets at risk.

Why this is a business issue

Smoke does not stop at borders. Fires in Indonesia affect air quality in Malaysia and Singapore, which turns a domestic crisis into a regional and diplomatic one. That pressure lands on the companies whose land and supply chains are linked to fires.

Markets are also paying attention. Many global buyers of palm oil and other commodities have made "No Deforestation, No Peat, No Exploitation" (NDPE) commitments and expect the same from their suppliers. A link to peat fires can put a supplier's market access, reputation and access to finance at risk. For exporters, prevention is no longer only a sustainability goal. It is part of staying in business.

What it will take to break the cycle

The good news is that we know what works. The solutions are not new, but they need to be in place before the fire season, not during it.

1. Stop using fire to clear land. Zero-burn land preparation, such as mechanical clearing, removes the most common source of ignition and keeps smoke out of the air.

2. Detect early. Satellite hotspot monitoring, ground patrols and water-level monitoring on peat help teams find risks before they become fires.

3. Prepare communities before the risk peaks. Socialization, training and simulation, and fire-control equipment make sure people, tools and response plans are ready when the dry season arrives. Communities living next to plantations are often the first to respond, and they need support to do it.

4. Restore peat hydrology. Blocking drainage canals and keeping peat wet addresses the root cause, not just the symptoms.

5. Work through the supply chain. Companies can map where their raw materials come from, identify suppliers in fire-prone areas, and work with them, including smallholders, on zero-burn practices and fire prevention. Traceability turns a commitment into something that can be checked and improved.

No single actor can do this alone. Government systems, companies and communities each hold part of the solution, and prevention works best when all three are prepared before the risk peaks.

Where we come in

At Nectary Sustainability Solutions, our field teams work directly with farmers, vendors and local stakeholders from Kalimantan to Sumatra, including fire-prone provinces such as Riau, South Sumatra and West Kalimantan. We help companies map their supply chains, assess sourcing risks with GIS and data, engage suppliers and smallholders, and build the systems behind NDPE, RSPO and ISPO commitments.

We see the same lesson in the field again and again: the work that prevents the next crisis happens long before the smoke appears.

Prevention costs less than the next emergency

Every haze season ends, and every year the temptation is to move on. But the next dry season is already coming. The question is whether the region will be ready this time.

Breaking the cycle means healthier lands, stronger economies and a more sustainable Southeast Asia. If your organization wants to understand its exposure to fire and haze risk in its supply chain, we would be glad to talk. Follow us for more insights from the field.