Satellite data has revealed significant methane emissions from some of Turkey’s largest rubbish dumps, raising questions about the country’s efforts to tackle the greenhouse gas as it prepares to host the COP31 climate summit.
Turkey will host the United Nations climate conference in Antalya from November 9 to 20, with reducing methane emissions identified as one of the priorities for the meeting.
One of the sites under scrutiny is the Seymen landfill, west of Istanbul, where thousands of tonnes of household waste are dumped daily. Although gas produced by decomposing rubbish is collected and used to generate electricity at a nearby power plant, satellite observations have detected substantial quantities of methane escaping into the atmosphere.
The findings highlight the challenge facing Turkey’s waste sector, where gas collection facilities are already operating at many large municipal landfills but have not prevented significant emissions.
Methane is the second-largest contributor to climate change after carbon dioxide. It is more than 80 times as potent as carbon dioxide over its first 20 years in the atmosphere, making reductions in methane emissions an important way to slow global warming in the near term.
According to Climate TRACE, a non-profit emissions tracking organization, Turkey is the world’s fifth-largest source of methane emissions from solid waste, behind China, the United States, Russia and Brazil.
Researchers at the University of California, Los Angeles, analyzed satellite observations and identified 70 methane plumes from Turkey’s 10 highest-emitting waste sites. The detected emission rates ranged from an average of 841 kilogrammes to 7.4 metric tonnes an hour.
Three of the sites were around Istanbul, while others were located near Ankara, Izmir and Antalya, the city hosting COP31.
Major landfills offer opportunities for emissions cuts
Tia Scarpelli, waste sector lead at emissions-monitoring organization Carbon Mapper, said reducing methane from landfills would require preventing organic waste from reaching dumps in the first place, alongside improving systems that collect gas already being produced.
She said the concentration of large emissions at a relatively small number of sites meant that targeting the biggest landfills could deliver substantial reductions in Turkey’s overall waste-related methane output.
Scarpelli recommended improving gas collection infrastructure and repairing damaged landfill covers and defective gas wells.
The UCLA research was based on publicly available Carbon Mapper observations collected by the Tanager-1 satellite between January 2025 and the end of May 2026.
At the Seymen landfill, the researchers recorded an average methane emission rate of approximately 7.4 tonnes an hour. That placed the site just below the highest-emitting landfill in a global ranking for 2025.
Scarpelli said the scale and persistence of the emissions detected at Seymen were particularly concerning.
Turkey’s Environment Ministry, however, questioned the use of the satellite readings to assess the landfill’s overall annual emissions. It said the observations were not continuous measurements and therefore could not establish the site’s yearly methane output.
The ministry also pointed to the government’s Zero Waste Initiative, which aims to increase recycling and reduce the volume of rubbish sent to landfills.
It said Turkey’s national waste recovery rate had increased from 13 per cent in 2017 to 37.53 per cent in 2025.
Questions over methane capture at Seymen
At Seymen, municipal waste operator ISTAC collects gas released as buried organic material decomposes. An energy company then burns the captured gas to produce electricity at a power plant that began operating in 2020.
The facility generates approximately 22,000 megawatt-hours of electricity monthly, according to a 2025 report by energy news website Enerji Gunlugu.
The Environment Ministry said ISTAC had a financial incentive to capture methane efficiently because the gas could be used to generate electricity.
However, ISTAC officials disputed whether the satellite observations accurately represented the landfill’s typical emissions.
Company official Aysen Erdincler said methane releases generally ranged between four and six tonnes an hour. She explained that a satellite reading of 12 tonnes an hour recorded on one day had pushed up the average calculated by researchers.
ISTAC head Fatih Ugur attributed the unusually high reading partly to maintenance work on methane collection pipes. He said about 30 hectares of the landfill had been left uncovered on the day of the observation.
He also cited low atmospheric pressure as a factor that could have contributed to the higher concentration of methane detected.
The Seymen facility receives about 8,500 tonnes of household waste daily from Istanbul. The city generates an average of approximately 20,000 tonnes each day, according to ISTAC.
Researchers have not established how much of the methane produced at the site is captured by its collection system. Erdincler, however, estimated that methane leakage at the landfill was usually around 25 per cent.
Turkey remains outside global methane agreement
Methane emissions from Turkey’s waste sector have increased considerably over the past decade.
World Bank data based on the European Commission’s EDGAR emissions database show that waste-related methane emissions in Turkey rose by nearly 25 per cent in the 10 years to 2024. The global increase over the same period was 6.5 per cent.
Turkey’s annual emissions from waste have remained at about 21 million tonnes of carbon dioxide equivalent since 2020.
The country is also not a participant in the Global Methane Pledge, launched at the COP26 climate summit in 2021. The initiative seeks a collective reduction of at least 30 per cent in global methane emissions from 2020 levels by 2030. More than 30 countries have subsequently supported national targets under the initiative.
Selim Yildirim, chief climate policy researcher at Ankara-based non-profit policy and media organisation D84, said Turkey had more developed waste disposal infrastructure than poorer countries but lagged behind much of Europe in waste management, recycling and recovery.
He said Turkey could still join the Global Methane Pledge during COP31, although signing up would not automatically translate into lower emissions.
Yildirim argued that the government would need to turn any commitment into practical measures, including regulations requiring landfill operators to capture and reuse methane.
Residents complain about landfill odour
The environmental impact of the Seymen landfill is also a concern for people living nearby.
Residents of the village of Seymen, about five kilometres from the waste site, have complained about the unpleasant smell from decomposing rubbish.
Although methane itself has no smell, organic waste can release other compounds that produce strong and unpleasant odours.
Soner Duz, a 46-year-old barber who lives in the area, said the smell was particularly disruptive during the summer, when residents kept their windows open to cope with the heat.
He said the odour often became noticeable in the early hours of the morning, sometimes waking residents around 4am or 5am.
Source: Reuters
