section_path: Environmental effects
section_name: Environmental effects
paragraph_text: Environmental effects
  
  The burning of fossil fuels has a number of negative externalities – harmful environmental impacts where the effects extend beyond the people using the fuel. These effects vary between different fuels. All fossil fuels release CO when they burn, thus accelerating climate change. Burning coal, and to a lesser extent oil and its derivatives, contributes to atmospheric particulate matter, smog and acid rain. Air pollution from fossil fuels in 2018 has been estimated to cost US$2.9 trillion, or 3.3% of the global gross domestic product (GDP).
  
  Climate change is largely driven by the release of greenhouse gases like CO, and the burning of fossil fuels is the main source of these emissions. In most parts of the world climate change is negatively impacting ecosystems. This includes contributing to the extinction of species and reducing people's ability to produce food, thus adding to the problem of world hunger. Continued rises in global temperatures will lead to further adverse effects on both ecosystems and people; the World Health Organization has said that climate change is the greatest threat to human health in the 21st century.
  
  Combustion of fossil fuels generates sulfuric and nitric acids, which fall to Earth as acid rain, impacting both natural areas and the built environment. Monuments and sculptures made from marble and limestone are particularly vulnerable, as the acids dissolve calcium carbonate.
  
  Fossil fuels also contain radioactive materials, mainly uranium and thorium, which are released into the atmosphere. In 2000, about 12,000 tonnes of thorium and 5,000 tonnes of uranium were released worldwide from burning coal. It is estimated that during 1982, US coal burning released 155 times as much radioactivity into the atmosphere as the Three Mile Island accident.
  
  Burning coal also generates large amounts of bottom ash and fly ash. These materials are used in a wide variety of applications (see Fly ash reuse), utilizing, for example, about 40% of the United States production.
  
  In addition to the effects that result from burning, the harvesting, processing, and distribution of fossil fuels also have environmental effects. Coal mining methods, particularly mountaintop removal and strip mining, have negative environmental impacts, and offshore oil drilling poses a hazard to aquatic organisms. Fossil fuel wells can contribute to methane release via fugitive gas emissions. Oil refineries also have negative environmental impacts, including air and water pollution. Coal is sometimes transported by diesel-powered locomotives, while crude oil is typically transported by tanker ships, requiring the combustion of additional fossil fuels.
  
  A variety of mitigating efforts have arisen to counter the negative effects of fossil fuels. This includes a movement to use alternative energy sources, such as renewable energy. Environmental regulation uses a variety of approaches to limit these emissions; for example, rules against releasing waste products like fly ash into the atmosphere.
  
  In December 2020, the United Nations released a report saying that despite the need to reduce greenhouse emissions, various governments are " doubling down " on fossil fuels, in some cases diverting over 50% of their COVID-19 recovery stimulus funding to fossil fuel production rather than to alternative energy. The UN secretary general António Guterres declared that "Humanity is waging war on nature. This is suicidal. Nature always strikes back – and it is already doing so with growing force and fury." He also claimed there is still cause for hope, anticipating the US plan to join other large emitters like China and the EU in adopting targets to reach net zero emissions by 2050.