The study is based on an analysis of satellite data as well as measurements of the air quality in Palangkaraya (Central Kalimantan). It is estimated that in the September-October 2015 period some 857 million tons of carbon dioxide was released due to the intense forest fires (exacerbated by El Nino-inflicted dry weather). In a "normal" year, Indonesia "only" releases about 860 million tons of carbon dioxide in the full-year.

Farmers and companies on the islands of Sumatra and Kalimantan traditionally use the slash-and-burn practice to clear land and make room for new plantations (usually for palm oil or pulp & paper plantations), a practice that is actually not allowed by Indonesian law but is made possible due to weak law enforcement and corruption. The man-made forest fires in June-October 2015 ran out of hand due to the dry weather that was brought to Southeast Asia by the strongest El Nino weather phenomenon since 1997. Last year's forest fires caused thick and toxic smog that spread to other parts of Southeast Asia, including Singapore and Kuala Lumpur in Malaysia.

Martin Wooster, earth observation science professor at King’s College London, said in 2015 global atmospheric CO2 concentration rose more than in any other year. He added that the Indonesian government needs to take more action to prevent such intense forest fires from happening as they jeopardize the health of people and have a severe negative impact on the environment.

Earlier, the World Bank stated that the man-made forest fires and toxic haze cost Indonesia IDR 221 trillion (approx. USD $16 billion or 1.9 percent of the country's GDP).

Disbanding the Indonesian Palm Oil Pledge (IPOP)

However, concerns have risen about the possibility of future forest fires after it was announced last week that the Indonesian Palm Oil Pledge (IPOP) is to be disbanded. IPOP was signed in 2014 by major palm oil producers (including Wilmar, Cargill, Golden Agri-Resources, Asian Agri, Astra Agro Lestari and Musim Mas) with the aim to set new limits on the clearance of land for plantations. Now, however, they have left the IPOP arguing that the Indonesian government has recently improved and strengthened regulations and standards (set in the Indonesian Sustainable Palm Oil system). Meanwhile, the nation's smallholders claim that the pact was too difficult to comply with.

Environmentalists, however, are concerned that the "dumping" of the pact could worsen the situation as it is expected to be more effective when companies come together on the issue rather than relying on the government. Moreover, the government's standard (Indonesian Sustainable Palm Oil system) is less strict as it only bans land clearing in primary forests and peat land, while IPOP also prohibits land clearing in forests that have regrown.

Indonesia is the world's largest producer and exporter of palm oil, a commodity that is used in a whole range of consumer products from food items to personal care products or biofuel. As such, the edible oil is a key foreign exchange earner for Indonesia, while the palm oil sector has created millions of jobs for Indonesians.