Global sulphur pollution decreasing

By: Christer Ågren

According to a new analysis of NASA satellite data by the Centre for Research on Energy and Clean Air (CREA) and Greenpeace India, global sulphur dioxide (SO₂) pollution from large point sources, such as smelters, coal-fired power plants and oil and gas use, fell by six per cent from 2018 to 2019.

The report ranks the world’s biggest emitters of SO₂, a poisonous air pollutant that increases risk of stroke, heart disease, lung cancer and premature death.

The NASA programme “Making Earth System Data Records for Use in Research Environments” (MEaSUREs) uses satellite measurements to detect and quantify major SO₂ pollution hotspots across the globe. NASA estimates that sources emitting less than 30 kilotons per year are not reliably detected and that the MEaSUREs catalogue accounts for about half of all known anthropogenic SO₂ emissions worldwide.

In 2019, emissions of SO₂ from large point sources decreased in all of the top three countries with the greatest emissions, namely India, Russia and China. India was responsible for more than one fifth of global SO₂ emissions from large point sources, with nearly twice the level of the world’s second largest emitter, Russia.

The primary reason for India’s high emissions is the expansion of coal-based electricity generation over the past two decades.

Although China was once the world’s biggest emitter of SO₂, the country’s emissions have plummeted by 87 per cent since their 2011 peak, primarily as a result of strengthened emissions standards. In 2019, however, China’s emissions fell by only 5 per cent, the slowest rate of decrease in the past decade.

Some other key findings of the analysis:

Table 1: The “dirty dozen” global hotspots of sulphur dioxide emissions (ktonnes).

Rank Country Emissions 2018 Emissions 2019 Change 2018–2019
1 India 6,329 5,953 -6%
2 Russia 3,635 3,362 -8%
3 China 2,263 2,156 -5%
4 Saudi Arabia 1,861 1,910 +3%
5 Mexico 1,809 1,873 +4%
6 Iran 1,977 1,746 -12%
7 South Africa 1,388 1,187 -15%
8 Turkey 938 1,072 +14%
9 United States 864 823 -5%
10 Kazakhstan 776 760 -2%
11 Ukraine 861 628 -27%
12 Australia 627 610 -3%

Table 2. Countries that emitted the greatest amount of SO2 from large point sources (ktonnes).

Rank Hotspot Country/region Source type Emissions 2019
1 Norilsk Russia Smelter 1,833
2 Rabigh Saudi Arabia Oil & Gas 652
3 Zagroz Iran Oil & Gas 558
4 Kriel South Africa Coal 504
5 Cantarell Mexico Oil & Gas 482
6 Singruali India Coal 479
7 Reforma Mexico Oil & Gas 415
8 Ilo Peru Smelter 414
9 Matimba South Africa Coal 362
10 Al Doha Kuwait Oil & Gas 351
11 Kemerkoy Turkey Coal 328
12 Afsin Elbistan Turkey Coal 307

SO₂ emissions in Turkey rose 14 per cent in 2019, marking the fourth consecutive year of increase. Between 2015 and 2019, Turkey’s share of coal-based electricity production increased by nearly 10 per cent. During this period SO₂ emissions doubled.

Ukraine, Serbia and Bulgaria are the biggest point source SO₂ emitters in Europe and rank among the world’s top 25 emitters. Bulgaria is the only EU country in the top 25 list of SO₂ polluters. Coal combustion is the primary SO₂ source in all three countries.

In 2019, the Norilsk smelter site in Russia was the biggest hotspot of SO₂ emissions in the world. The Rabigh region, an oil and gas-based SO₂ emission hotspot in Saudi Arabia, ranked second.

The Suralaya coal cluster in Banten, Indonesia was the largest SO₂ hotspot in Southeast Asia in 2019, followed closely by Singapore’s oil and gas refineries.

Lauri Myllyvirta, lead analyst at CREA, said: “These emissions tracked by satellites are affecting the health of millions of people, many who have had their lives cut short or their health compromised, showing the urgency of implementing stronger emissions regulations and transitioning to clean energy sources. Unfortunately, in some countries topping the list, like India, Mexico and South Africa, governments have continued to delay or weaken the implementation of emissions norms, even as the COVID-19 pandemic should have driven home the importance of respiratory health”.

The researchers conclude that governments must immediately halt investment in fossil fuels and shift to safer energy sources, such as wind and solar. At the same time, they must strengthen emissions standards and require the application of flue gas pollution control technology at power plants, smelters and other industrial SO₂ emitters.

Christer Ågren

Source: Greenpeace International press release, 8 October 2020.

The report ”Ranking the World’s Sulfur Dioxide (SO₂) Hotspots: 2019–2020” is available at:

In this issue


The clock is ticking to achieve the 1.5°C goal of the Paris Agreement. To be clear right from the start: this goal deserves every effort that mankind can pull off. In the name of realism, this is the goal we must focus on now, given the current level of progress in reducing greenhouse gases. However, damage to marine ecosystems will not be avoided even if we reach this goal1. In fact, damage already occurs at current levels of warming, as evidenced by the bleaching of coral reefs2. This may be an inconvenient truth when our current goal is 1.5°C.

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