Why the rain that would put out the fires is not coming

Everyone living under the smoke is asking the same question: when does it stop? Wang Jingyu, an assistant professor at Nanyang Technological University in Singapore, told France 24 that the answer sits in the ocean. A "super" El Nino, the Pacific pattern that shifts where rain falls across the region, has left sea surface temperatures cooler, and cooler water puts less moisture into the air. "Cooler sea surface temperature means we do not have enough evaporation from the ocean," he said. Typhoons further north then "absorbed moisture like a sponge", taking away what was left. His conclusion was short: "We do not have enough rain. The fire cannot be easily put out."

The smoke now sits over four countries: Indonesia, Malaysia, Singapore and East Timor. Jason Evans Tan, a deputy director at Singapore's National Environment Agency, said the city has had "the longest duration of air quality being in the unhealthy range since 2015", with the current spell starting on 5 October. Indonesia's transport ministry counts about 2,400 flights affected nationwide since mid-August, and says haze near airports cuts visibility enough to cause delays, disruption and cancellations.

The forest is emptying as the fire lines move. West Kalimantan's conservation agency and YIARI, a wildlife rescue foundation, carried 51 orangutans out of the province between 6 August and 19 October. The forestry ministry suggested the figure across Kalimantan could be as high as 96, though officials could not be reached to confirm it. On Saturday a 20-year-old male was sedated at Hampangen village in Central Kalimantan, examined and sent to a rehabilitation centre. Fenky Wirada, WWF Indonesia's conservation coordinator, described what his teams find when they go looking: "there are a few orangutans left in these small forest patches."

Why it matters

The forecast is the planning information here. If the rain is waiting on the ocean, this is a problem measured in weeks rather than days, so masks, closed classrooms and clinic visits are the normal week now, not the emergency. Anyone booking a domestic flight before the rains should expect the schedule to slip. What ends this season is either weather nobody controls or fewer fires being lit, and only the second one is a decision somebody makes.