A Fair World?

Solving the climate crisis may be one of the most important health opportunities of the 21st century<a href='https://link.springer.com/article/10.1186/s40985-016-0047-y' target='_blank'><img src='/img/courses/ref.svg'/></a>! In this chapter we look at how health and climate change are linked and why this is important<a href='https://www.drawdown.org/solutions/clean-cooking ' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(18)31788-4.pdf?utm_campaign=tleat19&utm_source=HubPage' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://ec.europa.eu/environment/integration/research/newsalert/pdf/24si_en.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>.

The smoke and soot produced when cooking with these fuels indoors can cause heart and lung diseases, as well as cancers and strokes<a href='https://www.who.int/news-room/fact-sheets/detail/household-air-pollution-and-health#:~:text=Around%202.4%20billion%20people%20worldwide,generates%20harmful%20household%20air%20pollution' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://apps.who.int/iris/bitstream/handle/10665/204717/9789241565233_eng.pdf;jsessionid=A0525CB4E990C12C098AACC4D33B983B?sequence=1' target='_blank'><img src='/img/courses/ref.svg'/></a>. Because of these diseases, indoor air pollution is responsible for 3.2 million early deaths every year<a href='https://www.who.int/news-room/fact-sheets/detail/household-air-pollution-and-health#:~:text=Around%202.4%20billion%20people%20worldwide,generates%20harmful%20household%20air%20pollution' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://cleancooking.org/wp-content/uploads/2022/08/Accelerating-Clean-Cooking-as-a-Nature-Based-Climate-Solution.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>, mostly in low-income countries countries, as shown below<a href='https://ourworldindata.org/indoor-air-pollution' target='_blank'><img src='/img/courses/ref.svg'/></a>.

These traditional cooking methods also contribute around 2% of global yearly greenhouse gas emissions, both through burning the fuels themselves and from the activities required to gather them<a href='https://doi.org/10.1186/s13705-022-00355-3' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://cleancooking.org/wp-content/uploads/2022/08/Accelerating-Clean-Cooking-as-a-Nature-Based-Climate-Solution.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>.

But it’s not only the amount of emissions produced from traditional cooking practices that cause problems. The types of pollution produced are problematic for both the climate and our health too<a href='https://doi.org/10.1007/s11356-020-10668-5' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.copenhagenconsensus.com/sites/default/files/pp_black_carbon_kandlikar_reynolds_grieshop_v.1.0.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>. Open fires and inefficient stoves often have poor air-circulation around them, leading to the production of “black carbon” (a major component of soot)<a href='https://pubs.acs.org/doi/abs/10.1021/es203388g' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.copenhagenconsensus.com/sites/default/files/pp_black_carbon_kandlikar_reynolds_grieshop_v.1.0.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>.

So, how much of a problem is black carbon for the environment?

Even though there is less black carbon in the atmosphere than CO₂, it is currently the second biggest contributor to global warming because it absorbs so much heat<a href='https://doi.org/10.1038/ngeo15' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.drawdown.org/solutions/clean-cooking ' target='_blank'><img src='/img/courses/ref.svg'/></a>. However, unlike CO₂, black carbon is quickly removed from the atmosphere by rain<a href='https://doi.org/10.1038/ngeo15' target='_blank'><img src='/img/courses/ref.svg'/></a>. While CO₂ continues to cause warming for hundreds of years after it has been emitted, the contribution of black carbon to global warming would end quickly if we stopped producing it<a href='https://doi.org/10.1126/science.1210026' target='_blank'><img src='/img/courses/ref.svg'/></a>.

This makes solutions that reduce black carbon emissions particularly promising: if all black carbon emissions stopped, the effects would be seen within only a matter of decades<a href='https://doi.org/10.1126/science.1210026' target='_blank'><img src='/img/courses/ref.svg'/></a>!

Improved cookstoves (either solar-powered or fuel-burning) can cut emissions by as much as 95%<a href='https://www.drawdown.org/solutions/clean-cooking ' target='_blank'><img src='/img/courses/ref.svg'/></a> as well as saving lives<a href='https://cleancooking.org/wp-content/uploads/2022/08/Accelerating-Clean-Cooking-as-a-Nature-Based-Climate-Solution.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>. By reducing black carbon and other pollutants, it is estimated that removing solid fuel cookstoves could avoid 10.5 million deaths between 2000 and 2050<a href='https://www.drawdown.org/solutions/clean-cooking ' target='_blank'><img src='/img/courses/ref.svg'/></a>.

There are even more benefits! Improved cookstoves use less fuel, which reduces the time people spend gathering firewood<a href='https://cleancooking.org/wp-content/uploads/2022/08/Accelerating-Clean-Cooking-as-a-Nature-Based-Climate-Solution.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>. This is a physically demanding and often dangerous task, especially for unaccompanied women<a href='https://cleancooking.org/wp-content/uploads/2022/08/Accelerating-Clean-Cooking-as-a-Nature-Based-Climate-Solution.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://genderandsecurity.org/sites/default/files/Patrick_-_SV_Firewood_Collection_in_Darfur.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Stopping indoor air pollution is only half of the story. Transport is a major source of outdoor air pollution<a href='https://doi.org/10.1016/S1352-2310(00)00551-3' target='_blank'><img src='/img/courses/ref.svg'/></a> and contributed around 15% of the global greenhouse gas emissions in 2019<a href='https://www.wri.org/research/state-climate-action-2021' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.ipcc.ch/report/ar6/wg3/downloads/report/IPCC_AR6_WGIII_Chapter10.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Swapping to electric cars is one possible solution, as they produce less pollution on the road<a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a>. However, they don’t solve other problems caused by cars, such as traffic accidents<a href='https://www.who.int/news-room/fact-sheets/detail/road-traffic-injuries' target='_blank'><img src='/img/courses/ref.svg'/></a>. They also only reduce emissions effectively if renewable energy is used to produce the electricity<a href='https://doi.org/10.1186/2190-4715-24-14' target='_blank'><img src='/img/courses/ref.svg'/></a>.

By contrast, taking public transport (such as buses, trams and trains) reduces pollution per passenger as well as traffic<a href='https://www.wri.org/research/state-climate-action-2021' target='_blank'><img src='/img/courses/ref.svg'/></a>. This is especially the case if the vehicles are full of passengers and are run on clean fuels or electricity<a href='https://www.wri.org/research/state-climate-action-2021' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Even better are active forms of transport, such as walking and cycling. These have the biggest positive impact on both health and solving climate change<a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://thedocs.worldbank.org/en/doc/c6de7aa3e8b4b081029f639767c1486c-0190062021/original/TDI-paper-Investing-for-Momentum-in-Active-Mobility-October-2021.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Walking and cycling reduce emissions, improve local air quality, and help prevent diseases related to inactive lifestyles<a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://thedocs.worldbank.org/en/doc/c6de7aa3e8b4b081029f639767c1486c-0190062021/original/TDI-paper-Investing-for-Momentum-in-Active-Mobility-October-2021.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Why should we link health and climate change?

The World Health Organisation estimates that air pollution causes as many as one in eight deaths<a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a>, as well as contributing to climate change<a href='https://www.who.int/publications/i/item/WHO-HEP-ECH-EHD-21.02' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Politicians tend to avoid strong climate change policies due to their perceived costs, and because the climate benefits to their country are only felt if many other countries do the same<a href='https://science.sciencemag.org/content/162/3859/1243' target='_blank'><img src='/img/courses/ref.svg'/></a>.

On the other hand, the health benefits of reducing air pollutionare felt quickly and by the people in that country<a href='https://doi.org/10.1513/annalsats.201907-538cme' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Therefore, thinking about the immediate health benefits of reducing air pollution may help persuade politicians to take action on emissions. These policies aim to improve public health, but they also tackle climate change. Win-win!

Meeting the targets of the Paris Agreement on climate change would save over one million lives a year from air pollution by 2050<a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a>. And these policies would more than pay for themselves in gains from improved health, such as increased productivity of healthy workers and reduced spending on healthcare<a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.sciencedirect.com/science/article/pii/S2542519618300299' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Thinking about both the climate and human health could also persuade politicians to reduce deforestation.

Not only does cutting down trees produce carbon emissions, but it also has the potential to contribute to the spread of diseases<a href='https://doi.org/10.1126/science.1217962' target='_blank'><img src='/img/courses/ref.svg'/></a>. This is because around 75% of newly emerging infectious diseases that affect humans come from animals<a href='https://doi.org/10.3201%2Feid1112.040789' target='_blank'><img src='/img/courses/ref.svg'/></a>. These are called “zoonoses”<a href='https://doi.org/10.3201%2Feid1112.040789' target='_blank'><img src='/img/courses/ref.svg'/></a>.

When forests are cut down, and roads built within them, humans come into much closer contact with the animals that live there which increases the likelihood of diseases.spreading between people and animals<a href='https://doi.org/10.3201%2Feid1112.040789' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://royalsocietypublishing.org/doi/full/10.1098/rspb.2018.2351' target='_blank'><img src='/img/courses/ref.svg'/></a>.

In the recent past, human impacts on the natural world have been linked to a number of viral epidemics and pandemics including COVID-19 (2019-2023), Zika (2015-19) and SARS (2002-04)<a href='https://reader.elsevier.com/reader/sd/pii/S0169534720301348?token=E0A6761B89F7EF8FEB2B234556BAC4D719EC9D2726F7C4551B668D1DD7400C694626897E97B08628FA1D983AE5AF757D' target='_blank'><img src='/img/courses/ref.svg'/></a>. Outbreaks of Ebola and Malaria have also been linked to deforestation<a href='https://www.nature.com/articles/srep41613' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.nature.com/articles/s41598-017-14727-9' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://royalsocietypublishing.org/doi/full/10.1098/rspb.2018.2351' target='_blank'><img src='/img/courses/ref.svg'/></a>.

Preventing the loss of forests could reduce the chance of future disease outbreaks at the same time as limiting carbon emissions<a href='https://doi.org/10.1126/science.1217962' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://www.nature.com/articles/s41598-017-14727-9' target='_blank'><img src='/img/courses/ref.svg'/></a>.

And that’s not the only health reason for conserving nature. A growing body of evidence suggests that experiencing nature can have great benefits for our physical and mental wellbeing<a href='https://www.frontiersin.org/articles/10.3389/fpsyg.2014.01178/full' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='' target='_blank'><img src='/img/courses/ref.svg'/></a>. Put simply, being around plants and animals makes us happy<a href='https://www.frontiersin.org/articles/10.3389/fpsyg.2014.01178/full' target='_blank'><img src='/img/courses/ref.svg'/></a>!

Clean cookstoves, transport choices and forest conservation are just three of the ways we can improve global health and slow climate change at the same time<a href='https://www.who.int/publications-detail/cop24-special-report-health-climate-change' target='_blank'><img src='/img/courses/ref.svg'/></a><a href='https://ec.europa.eu/environment/integration/research/newsalert/pdf/24si_en.pdf' target='_blank'><img src='/img/courses/ref.svg'/></a>. Understanding and making the most of these links may motivate politicians to take rapid and effective action on the climate crisis<a href='https://link.springer.com/article/10.1186/s40985-016-0047-y' target='_blank'><img src='/img/courses/ref.svg'/></a>.