Global Greenhouse Gas Emissions Continue to Rise: Key Emitters and Industries Revealed

As world leaders convene in Antalya, Turkiye, for COP31, the United Nations' annual climate summit running from November 9 to 20, global emissions are on an upward trajectory. In 2025, the world released 54.1 billion tonnes of greenhouse gases, a 0.7 percent increase from the previous year and a substantial 68.5 percent rise since 1990, according to data from the European Commission’s Joint Research Centre (JRC) and the International Energy Agency (IEA). These gases, primarily carbon dioxide and methane, trap heat, leading to rising global temperatures and exacerbating extreme weather events such as heatwaves, droughts, and floods.

Carbon dioxide (CO2) constituted the largest portion of global greenhouse gas emissions in 2025, accounting for 73.8 percent. Its release is largely attributed to the burning of fossil fuels like coal, oil, and gas, as well as deforestation. Methane (CH4) followed, making up 17.6 percent of emissions, with nitrous oxide (N2O) at 5.3 percent and fluorinated gases (F-gases) at 3.3 percent. Since 1990, global CO2 emissions have surged by 76.3 percent, as reported by the JRC.

The accumulation of these gases in the atmosphere intensifies heat retention. The World Meteorological Organization (WMO) reports that in 2025, the heat stored in the world's oceans reached a record high, with the rate of ocean warming accelerating significantly over the past two decades. Extreme weather events in 2026 have already resulted in tens of thousands of deaths and displaced millions. Europe experienced over 30,000 excess deaths due to heatwaves, droughts, and wildfires between May and August, with France alone evacuating 220,000 people. In the Himalayas, a glacier collapse and subsequent flash flood on August 26 killed over 1,500 people in Nepal and left approximately 5,600 missing. Typhoons and tropical storms also caused widespread devastation, with Typhoon Bavi displacing three million in China and killing 26 in the Philippines, and Tropical Storm Maysak causing 171 deaths and over $3 billion in losses in China. Morocco faced displacement of over 180,000 due to floods and windstorms, while North America recorded 174 deaths from extreme cold and snow.

Globally, greenhouse gas emissions have more than doubled since 1970, increasing from approximately 23 billion tonnes to 54.1 billion tonnes in 2025, according to the JRC. The power industry is the leading contributor, responsible for nearly 30 percent of global emissions in 2025, with its emissions quadrupling since 1970, fueled by escalating electricity demand in rapidly developing economies like China and India. Industry, encompassing manufacturing and mining, ranks second at 21 percent, stemming from fuel combustion in factories and processes like cement, metal, and chemical production. Industrial emissions saw a sharp rise in the 2000s with China's manufacturing boom. Transport, including cars, shipping, and aviation, is the third-largest source at 16 percent. Collectively, these three sectors account for about two-thirds of global emissions. Other sources include agriculture (12 percent), fossil fuel extraction (11 percent), buildings (6.6 percent), and waste (3.6 percent). Emissions have seen only a few dips since 1970, notably in the early 1980s, after the 2008 financial crisis, and during the COVID-19 pandemic in 2020, with subsequent rebounds.

In 2025, China, the United States, and India were the top three emitters, collectively responsible for nearly half of the world's greenhouse gases. China emitted close to 16 billion tonnes (29.5 percent), the US emitted 6.02 billion tonnes (11.1 percent), and India emitted 4.51 billion tonnes (8.3 percent). The European Union's 27 countries contributed 5.8 percent, followed by Russia (4.8 percent), Indonesia (2.5 percent), Brazil (2.4 percent), and Iran (2.1 percent). International shipping and aviation, not attributed to any single country, jointly produced 2.6 percent of global emissions, surpassing the output of most individual nations. Historically, the Industrial Revolution in the 18th and 19th centuries initially drove emissions in the West, particularly the United Kingdom and the US. Post-World War II, global emissions rose sharply, more than doubling since 1970. China's emissions escalated in the early 2000s, making it the world's largest emitter, surpassing the US. However, over the long term, the US has historically produced 23.5 percent of all CO2 emissions since the mid-18th century, compared to China's 15.4 percent, according to the Global Carbon Budget.

In China, the power sector is the primary source of emissions, contributing 42 percent of the country's nearly 16 billion tonnes. Industry accounts for 31 percent, and fuel production for 9.5 percent. In September 2025, Chinese President Xi Jinping announced a pledge to reduce the country's greenhouse gas emissions by 7 to 10 percent from their peak by 2035. In the US, transport is the largest contributor at 29 percent, largely due to cars and trucks. The power sector accounts for 26 percent, and industry for 14 percent. India's emissions are heavily influenced by its reliance on coal for electricity, with the power sector producing 35 percent, followed by industry at 24 percent and agriculture at 19 percent.