a key category, it is not split between cars and lorries as is done in some countries. In 2021 the UNFCCC asked Turkey why it reported negligible indirect GHGs (carbon monoxide, nitrogen oxides, non-methane volatile organic compounds and sulfur oxides) in 2018. Greenhouse gas sources Turkey emitted 524 Mt of GHG in 2020, which is higher than would be sustainable under a global carbon budget. Per-person gross emissions are above the world average, at 6.3 t in 2020. Turkey's cumulative CO2 emissions are estimated at around 11 Gt, which is less than 1% of the world's cumulative total (Turkey's population is about 1% of world population). Turkey's emissions can be looked at from different perspectives to the standard IPCC classification: for example a 2021 study by Izmir University of Economics estimated that food, "from farm to fork", accounts for about a third of national emissions. This is similar to the global emissions share of food. Fossil fuels Burning coal in Turkey was the largest contributor to fossil-fuel emissions in 2020, followed by oil and natural gas. That year, Turkey's energy sector emitted over 70% of the country's GHG, mostly through electricity generation, followed by transport. In contrast agriculture contributed 14% of emissions, and industrial processes and product use (IPPU) slightly less. Carbon capture and storage is not economically viable, since the country has no carbon pricing. The GHG emission intensity of energy consumption is higher than in the EU. From 2023 Turkey expects to greatly increase gas production. In 2021, IEA head Fatih Birol called for fossil fuel producing countries to include limiting methane leaks in their climate pledges, for example the United States is doing this. Production of public heat and electricity emitted 131 megatonnes of e in 2020, mainly through coal burning. In 2020, emission intensity was about 440 g/kWh, around the average for G20 countries. Investment in wind and solar is hampered by subsidies for coal. A trial of reinjecting geothermal gas back into the ground is planned for 2021. Subsidised coal burnt by poor families gives off black carbon (a contributor to climate change) and other local air pollution. Residential fuel, such as natural gas and coal, contributed 50 Mt e in 2020. Burning fossil fuels such as coal and natural gas to heat commercial and institutional buildings emitted 14 Mt e in 2020. According to the Ministry of Energy and Natural Resources, "Our country aims