Effects of climate change on human health

342: 19: 612: 1128: 1166:(PTSD). Scientific studies have linked mental health to several climate-related exposures. These include heat, humidity, rainfall, drought, wildfires and floods. The indirect pathway can be disruption to economic and social activities. An example is when an area of farmland is less able to produce food. The third pathway can be of mere awareness of the climate change threat, even by individuals who are not otherwise affected by it. This especially manifests in the form of anxiety over the quality of life for future generations. 1485: 5806:

Emmerling, Johannes; Ebi, Kristie; Hasegawa, Tomoko; Havlík, Petr; Humpenoder, Florian; Da Silva, Lara Aleluia; Smith, Steve; Stehfest, Elke; Bosetti, Valentina; Eom, Jiyong; Gernaat, David; Masui, Toshihiko; Rogelj, Joeri; Strefler, Jessica; Drouet, Laurent; Krey, Volker; Luderer, Gunnar; Harmsen, Mathijs; Takahashi, Kiyoshi; Baumstark, Lavinia; Doelman, Johnathan C.; Kainuma, Mikiko; Klimont, Zbigniew; Marangoni, Giacomo; Lotze-Campen, Hermann; Obersteiner, Michael; Tabeau, Andrzej; Tavoni, Massimo (1 February 2017).

1299: 817: 7657: 1217: 994: 9406: 9458: 9394: 1013:) and ambient temperature is complex. Changes in air temperature and water content affect the air's chemistry and the rates of chemical reactions that create and remove ozone. Many chemical reaction rates increase with temperature and lead to increased ozone production. Climate change projections show that rising temperatures and water vapour in the atmosphere will likely increase surface ozone in polluted areas like the eastern United States. 9430: 9418: 472: 4424:

Lingzhi; Ciampi, Luisa; Dalin, Carole; Dasandi, Niheer; Dasgupta, Shouro; Davies, Michael; Dominguez-Salas, Paula; Dubrow, Robert; Ebi, Kristie L; Eckelman, Matthew; Ekins, Paul; Escobar, Luis E; Georgeson, Lucien; Grace, Delia; Graham, Hilary; Gunther, Samuel H; Hartinger, Stella; He, Kehan; Heaviside, Clare; Hess, Jeremy; Hsu, Shih-Che; Jankin, Slava; Jimenez, Marcia P; Kelman, Ilan; et al. (October 2021).

1325:, hepatoxins, cytotoxins or endotoxins that can cause serious and sometimes fatal neurological, liver and digestive diseases in humans. Cyanobacteria grow best in warmer temperatures (especially above 25 degrees Celsius), and so areas of the world that are experiencing general warming as a result of climate change are also experiencing harmful algal blooms more frequently and for longer periods of time. 5636: 5172: 3560: 9470: 931:. Scientists found in 2022 that rising temperatures are increasing the areas where dengue fever, malaria and other mosquito-carried diseases are able to spread. Warmer temperatures are also advancing to higher elevations, allowing mosquitoes to survive in places that were previously in hospitable to them. This risks malaria returning to areas where it was previously eradicated. 1052:, and other cardiopulmonary problems. High ozone concentrations irritate the lungs and thus affect respiratory function, especially among people with asthma. People who are most at risk from breathing in ozone air pollution are those with respiratory issues, children, older adults and those who typically spend long periods of time outside such as construction workers. 1523:, and childhood undernutrition. The authors estimated that climate change was projected to cause an additional 250,000 deaths per year between 2030 and 2050 but also stated that "these numbers do not represent a prediction of the overall impacts of climate change on health, since we could not quantify several important causal pathways". 450:) are more at risk when faced with high temperatures and ought to be extra careful as cognitive performance has been shown to be differentially affected by heat. People with diabetes and those who are overweight, have sleep deprivation, or have cardiovascular/cerebrovascular conditions should avoid too much heat exposure. 426:

that is too high means that human bodies would no longer be able to adequately cool the skin. A wet bulb temperature of 35 °C is regarded as the limit for humans (called the "physiological threshold for human adaptability" to heat and humidity). As of 2020, only two weather stations had recorded

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On the other hand, ozone concentrations could decrease in a warming climate if anthropogenic ozone-precursor emissions (e.g., nitrogen oxides) continue to decrease through implementation of policies and practices. Therefore, future surface ozone concentrations depend on the climate change mitigation

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With regards to sporting activities, it has been observed that "hot weather reduces the likelihood of engaging in exercise". Furthermore, participating in sports during excessive heat can lead to injury or even death. It is also well established that regular physical activity is beneficial for human

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Romanello, Marina; McGushin, Alice; Di Napoli, Claudia; Drummond, Paul; Hughes, Nick; Jamart, Louis; Kennard, Harry; Lampard, Pete; Solano Rodriguez, Baltazar; Arnell, Nigel; Ayeb-Karlsson, Sonja; Belesova, Kristine; Cai, Wenjia; Campbell-Lendrum, Diarmid; Capstick, Stuart; Chambers, Jonathan; Chu,

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High surface ozone concentrations often occur during heat waves in the United States. Throughout much of the eastern United States, ozone concentrations during heat waves are at least 20% higher than the summer average. Broadly speaking, surface ozone levels are higher in cities with high levels of

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investigated change in labour capacity as an indicator. It found that during 2021, high temperature reduced global potential labour hours by 470 billion – a 37% increase compared to the average annual loss that occurred during the 1990s. Occupational heat exposure especially affects laborers in the

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came to similar conclusions, reporting that the "numbers of people in regions across the world affected by extreme heat stress – a potentially fatal combination of heat and humidity – could increase" "from 68 million today to around one billion" if the world's temperature rise reaches 2°C, although

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Research shows that health professionals around the world agree that climate change is real, is caused by humans, and is causing increased health problems in their communities. Health professionals can act by informing people about health harms and ways to address them, by lobbying leaders to take

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for whole families, particularly those headed by women. It can also reduce the earning capacity and economic stability of people. Populations over 65 years of age are particularly vulnerable to heat and other health effects of climate change. Health risks are unevenly distributed across the world.

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The replacement of coal-based energy with renewables can lower the number of premature deaths caused by air pollution and decrease health costs associated with coal-related respiratory diseases. This switch to renewable energy is crucial, as air pollution is responsible for over 13 million deaths

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measures are significant, having been described as "the greatest global health opportunity" of the 21st century. Measures can not only mitigate future health effects from climate change but also improve health directly. Climate change mitigation is interconnected with various co-benefits (such as

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Further study found that even a wet bulb temperature of 31 degrees is dangerous, even for young and healthy people. This threshold is not uniform for all and depend on many factors including environmental factors, activity and age. If the global temperature will rise by 3 degrees (the most likely

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Riahi, Keywan; van Vuuren, Detlef P.; Kriegler, Elmar; Edmonds, Jae; O'Neill, Brian C.; Fujimori, Shinichiro; Bauer, Nico; Calvin, Katherine; Dellink, Rob; Fricko, Oliver; Lutz, Wolfgang; Popp, Alexander; Cuaresma, Jesus Crespo; KC, Samir; Leimbach, Marian; Jiang, Leiwen; Kram, Tom; Rao, Shilpa;

310:. The projected annual average temperature of above 29 °C for these regions would be outside the "human temperature niche" – a suggested range for climate biologically suitable for humans based on historical data of mean annual temperatures (MAT) – and the most affected regions have little 206:

These health risks vary across the world and between different groups of people. For example, differences in health service provision or economic development will result in different health risks for people in different regions, with less developed countries facing greater health risks. In many

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The effects of climate change on human health can be grouped into direct and indirect effects. Both types of effects interact with social dynamics. The combination of effects and social dynamics determines the eventual health outcomes. Mechanisms and social dynamics are explained further below:

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A headline finding in 2021 regarding marine food security stated that: "In 2018–20, nearly 70% of countries showed increases in average sea surface temperature in their territorial waters compared within 2003–05, reflecting an increasing threat to their marine food productivity and marine food

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does not quantify this number in its chapter on food security. A modelling study from 2016 found "a climate change–associated net increase of 529,000 adult deaths worldwide from expected reductions in food availability (particularly fruit and vegetables) by 2050, as compared with a reference

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Mortality due to heat waves could be reduced if buildings were better designed to modify the internal climate, or if the occupants were better educated about the issues, so they can take action on time. Heatwave early warning and response systems are important elements of heat action plans.

1639:, it can help encourage engagement if it is framed as a health concern, rather than as an environmental issue. This is especially the case when comparing a health related framing to one that emphasised environmental doom, as was common in the media at least up until 2017. Communicating the 1429:

may result in an annual reduction of 1.18 million air pollution-related deaths, 5.86 million diet-related deaths, and 1.15 million deaths due to physical inactivity, across nine countries by 2040. These benefits were attributable to the mitigation of direct greenhouse gas emissions and the

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etc.), waterborne diseases (transmitted via viruses or bacteria through water), and food-borne diseases.(spread through pathogens via food) Climate change affects the distribution of these diseases due to the expanding geographic range and seasonality of these diseases and their

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accompanying actions that reduce exposure to harmful pollutants, as well as improved diets and safe physical activity. Globally the cost of limiting warming to 2 °C is less than the value of the extra years of life due to cleaner air - and in India and China much less.

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effect. This results from the way many cities are built. For example, they often have extensive areas of asphalt, reduced greenery along with many large heat-retaining buildings that physically block cooling breezes and ventilation. Lack of water features are another cause.

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Lacressonnière, Gwendoline; Watson, Laura; Gauss, Michael; Engardt, Magnuz; Andersson, Camilla; Beekmann, Matthias; Colette, Augustin; Foret, Gilles; Josse, Béatrice; Marécal, Virginie; Nyiri, Agnes; Siour, Guillaume; Sobolowski, Stefan; Vautard, Robert (February 1, 2017).

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in some regions. Furthermore, tropical cyclones and storm tracks are moving towards the poles. This means some regions will see large changes in maximum wind speeds. Scientists expect there will be fewer tropical cyclones. But they expect their strength to increase. (see

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are expected to become more severe in the future when they do occur. However, the interactions between rainfall and flooding are complex. In some regions, flooding is expected to become rarer. This depends on several factors, such as changes in rain and snowmelt, but also

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Studies have found that communications on climate change that present it as a health concern rather than just an environmental matter are more likely to engage the public. The health effects of climate change are increasingly a matter of concern for the international

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and economically disadvantaged communities). As a result, people of disadvantaged sociodemographic groups experience unequal risks. Often these people will have made a disproportionately low contribution toward man-made global warming, thus leading to concerns over

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found that climate change does not affect people's health in an equal way. The greatest impact tends to fall on the most vulnerable such as the poor, women, children, the elderly, people with pre-existing health concerns, other minorities and outdoor workers.

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places, the combination of lower socioeconomic status and cultural gender roles result in increased health risks to women and girls as a result of climate change, compared to those faced by men and boys (although the converse may apply in other instances).

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and methane contribute both to global warming and to air pollution. Their mitigation can bring benefits in terms of limiting global temperature increases as well as improving air quality. Implementation of the climate pledges made in the run-up to the

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show a warming of 1.09 °C (range: 0.95 to 1.20 °C) from 1850–1900 to 2011–2020, based on multiple independently produced datasets. The trend is faster since the 1970s than in any other 50-year period over at least the last 2000 years.

960:. There are numerous predictions for how indoor air pollutants will change in future. Models have attempted to predict how the forecasted scenarios will affect indoor air quality and indoor comfort parameters such as humidity and temperature. 1368:

It is possible that a potential health benefit from global warming could result from fewer cold days in winter: This could lead to some mental health benefits. However, the evidence on this correlation is regarded as inconsistent in 2022.

6646:; Niamir, Leila; Bai, Xuemei; Callaghan, Max; Cullen, Jonathan; Díaz-José, Julio; Figueroa, Maria; Grubler, Arnulf; Lamb, William F.; Leip, Adrian; Masanet, Eric; Mata, Érika; Mattauch, Linus; Minx, Jan C.; Mirasgedis, Sebastian (2022). 506:

Cities are often on the front-line of climate change due to their densely concentrated populations, the urban heat island effect, their frequent proximity to coasts and waterways, and reliance on ageing physical infrastructure networks.

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and other causes of illness, injury or death. Heat waves and extreme weather events have a big impact on health both directly and indirectly. When people are exposed to higher temperatures for longer time periods they might experience

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Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, and O. Zolina, 2021:

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with all its associated health problems. Food insecurity is increasing at the global level (some of the underlying causes are related to climate change, others are not) and about 720–811 million people suffered from hunger in 2020.

1232:. The elevated concentration in this figure, 689 ppm, is over 50% greater than the current levels, yet it is expected to be approached under the "mid-range" climate change scenarios, and will be surpassed in the high-emission one. 1667:

had issued a 100-page report on global warming and human health back in 1989. By the early years of the 21st century, climate change was increasingly addressed as a public health concern at a global level, for example in 2006 at

1317:. Also, during droughts, surface waters are even more susceptible to harmful algal blooms and microorganisms. Algal blooms increase water turbidity, suffocating aquatic plants, and can deplete oxygen, killing fish. Some kinds of 583:

Working in extreme heat can lead to labor force productivity decreases as well as participation because employees' health may be weaker due to heat related health problems, such as dehydration, fatigue, dizziness, and confusion.

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The social vulnerability of people is related to certain health patterns. For example there are "demographic, socioeconomic, housing, health (such as pre-existing health conditions), neighbourhood, and geographical factors".

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Climate change has diverse effects on migration activities, and can lead to decreases or increases in the number of people who migrate. Migration activities can have an effect on health and well-being, in particular for

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Crimmins, A.; Balbus, J.; Gamble, J.L.; Beard, C.B.; Bell, J.E.; Dodgen, D.; Eisen, R.J.; Fann, N.; Hawkins, M.D.; Herring, S.C.; Jantarasami, L.; Mills, D.M.; Saha, S.; Sarofim, M.C.; Trtanj, J.; Ziska, L. (2016).

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to anthropogenic climate change is highest in changes in frequency or magnitude of extreme heat and cold events with some confidence in increases in heavy precipitation and increases in the intensity of droughts.

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35 °C wet-bulb temperatures, and only very briefly, but the frequency and duration of these events is expected to rise with ongoing climate change. Global warming above 1.5 degrees risks making parts of the

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A 2023 study estimated that climate change since 1960–1990 has put over 600 million people (9% of the global population) outside the "temperature niche" - the average temperature range at which humans flourish.

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deaths worldwide in 2004. Total attributable mortality was about 0.2% of deaths in 2004; of these, 85% were child deaths. The effects of more frequent and extreme storms were excluded from this study.

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Kemp, Luke; Xu, Chi; Depledge, Joanna; Ebi, Kristie L.; Gibbins, Goodwin; Kohler, Timothy A.; Rockström, Johan; Scheffer, Marten; Schellnhuber, Hans Joachim; Steffen, Will; Lenton, Timothy M. (2022).

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and wellbeing are being documented as the consequences of climate change become more tangible and impactful. This is especially the case for vulnerable populations and those with pre-existing serious

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Knutson, Thomas; Camargo, Suzana J.; Chan, Johnny C. L.; Emanuel, Kerry; Ho, Chang-Hoi; Kossin, James; Mohapatra, Mrutyunjay; Satoh, Masaki; Sugi, Masato; Walsh, Kevin; Wu, Liguang (August 6, 2019).

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Due to climate change temperatures rose in Europe and heat mortality increased. From 2003–12 to 2013–22 alone, it increased by 17 deaths per 100,000 people, while women are more vulnerable than men.

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Climate Change and Land: an IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems

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The risk of dying from chronic lung disease during a heat wave has been estimated at 1.8–8.2% higher compared to average summer temperatures. An 8% increase in hospitalization rate for people with

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and associated health benefits) and how it is carried out (in terms of e.g. policymaking) could also determine its effect on living standards (whether and how inequality and poverty are reduced).

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Hamilton, Ian; Kennard, Harry; McGushin, Alice; Höglund-Isaksson, Lena; Kiesewetter, Gregor; Lott, Melissa; Milner, James; Purohit, Pallav; Rafaj, Peter; Sharma, Rohit; Springmann, Marco (2021).

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excess deaths during 2018. Climate change mitigation policies can lead to lower emissions of co-emitted air pollutants, for instance by shifting away from fossil fuel combustion. Gases such as

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and all-cause mortality. Heat-related deaths in people older than 65 years reached a record high of an estimated 345 000 deaths in 2019". More than 70,000 Europeans died as a result of the

2142: 1158:. There are three broad pathways by which these effects can take place: directly, indirectly or via awareness. The direct pathway includes stress-related conditions caused by exposure to 722:(which were likely more severe because of climate change) affected people's health directly and indirectly. There were outbreaks of diseases like malaria, dengue, and other skin diseases. 3103: 2659: 1179:

lengths and concentrations in some regions of the world. For example, in northern mid-latitudes regions, the spring pollen season is now starting earlier. This can affect people with

1422:: "obesity, diabetes, heart disease, and cancer, which are in part related to physical inactivity, may be reduced by a switch to low-carbon transport—including walking and cycling." 6909: 3520: 1087:, for example failed crops due to more extreme weather events. This comes on top of other coexisting crises that reduce food security in many regions. Less food security means more 435:

scenario if things will not change), temperatures will exceed this limit at large areas in Pakistan, India, China, sub-Saharan Africa, United States, Australia, and South America.

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include people with low incomes, minority groups, women (in particular pregnant women), children, older adults (over 65 years old), people with chronic diseases, disabilities and

6265:"Effects of ocean acidification on the growth, photosynthetic performance, and domoic acid production of the diatom Pseudo-nitzschia australis from the California Current System" 9130: 4405:

Cissé, G., R. McLeman, H. Adams, P. Aldunce, K. Bowen, D. Campbell-Lendrum, S. Clayton, K.L. Ebi, J. Hess, C. Huang, Q. Liu, G. McGregor, J. Semenza, and M.C. Tirado, 2022:

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