Climate change, industry and society
This article is about climate change, industry and society.
Systems and sectors
Health
Humans are exposed to climate change through changing weather patterns and indirectly through changes in water, air and food quality and changes in ecosystems, agriculture, industry and settlements and the economy. According to a literature assessment by Confalonieri et al., the effects of climate change to date have been small, but are projected to progressively increase in all countries and regions.With high confidence, Confalonieri et al. concluded that climate change had altered the seasonal distribution of some allergenic pollen species. With medium confidence, they concluded that climate change had:
- altered the distribution of some infectious disease vectors
- increased heatwave-related deaths
- the health status of millions of people would be affected through, for example, increases in malnutrition; increased deaths, diseases and injury due to extreme weather events; increased burden of diarrhoeal diseases; increased frequency of cardio-respiratory diseases due to high concentrations of ground-level ozone in urban areas related to climate change; and altered spatial distribution of some infectious diseases.
- climate change would bring some benefits in temperate areas, such as fewer deaths from cold exposure, and some mixed effects such as changes in range and transmission potential of malaria in Africa. Overall, IPCC expected that benefits would be outweighed by negative health effects of rising temperatures, especially in developing countries.
According to a 2009 journal paper by UCL academics, climate change and global warming pose the biggest threat to human health in the 21st century.
Malnutrition
With high confidence, Confalonieri et al. projected that malnutrition would increase due to climate change. This link is associated with climate variability and change. Drought reduces variety in diets and reduces overall consumption. This can lead to micronutrient deficiencies.The World Health Organization conducted a regional and global assessment to quantify the amount of premature morbidity and mortality due to a range of factors, including climate change. Projections were made over future climate change impacts. Limited adjustments for adaptation were included in the estimates based on these projections. Projected relative risks attributable to climate change in 2030 varied by health outcome and region. Risks were largely negative, with most of the projected disease burden due to increases in diarrhoeal disease and malnutrition. These increases were primarily in low-income populations already experiencing a large burden of disease.
Extreme events
With high confidence, Confalonieri et al. projected that climate change would increase the number of people suffering from death, disease and injury from heat waves, floods, storms, fires and droughts.;Floods and weather disasters
Floods are low-probability, high-impact events that can overwhelm physical infrastructure and human communities. Confalonieri et al. reported that major storm and flood disasters have occurred in the last two decades.
The impacts of weather disasters is considerable and unequally distributed. For example, natural disasters have been shown to result in increased domestic violence against - and post-traumatic stress disorders in – women. In terms of deaths and populations affected, floods and tropical cyclones have the greatest impact in South Asia and Latin America. Vulnerability to weather disasters depends on the attributes of the person at risk, including where they live and their age, as well as other social and environmental factors. High-density populations in low-lying coastal regions experience a high health burden from weather disasters.
;Heatwaves
Hot days, hot nights and heatwaves have become more frequent. Heatwaves are associated with marked short-term increases in mortality. For example, in August 2003, a heatwave in Europe resulted in excess mortality in the range of 35,000 total deaths.
Heat-related morbidity and mortality is projected to increase. The health burden could be relatively small for moderate heatwaves in temperate regions, because deaths occur primarily in susceptible persons.
;Drought
The effects of drought on health include deaths, malnutrition, infectious diseases and respiratory diseases. Countries within the "Meningitis Belt" in semi-arid sub-Saharan Africa experience the highest endemicity and epidemic frequency of meningococcal meningitis in Africa, although other areas in the Rift Valley, the Great Lakes, and southern Africa are also affected. The spatial distribution, intensity, and seasonality of meningococcal meningitis appear to be strongly linked to climate and environmental factors, particularly drought. The cause of this link is not fully understood.
;Fires
In some regions, changes in temperature and precipitation are projected to increase the frequency and severity of fire events. Forest and bush fires cause burns, damage from smoke inhalation and other injuries.
Spread of disease
Global warming may extend the favourable zones for vectors conveying infectious disease such as dengue fever, West Nile virus, and malaria. In poorer countries, this may simply lead to higher incidence of such diseases. In richer countries, where such diseases have been eliminated or kept in check by vaccination, draining swamps and using pesticides, the consequences may be felt more in economic than health terms. The World Health Organization says global warming could lead to a major increase in insect-borne diseases in Britain and Europe, as northern Europe becomes warmer, ticks—which carry encephalitis and lyme disease—and sandflies—which carry visceral leishmaniasis—are likely to move in. However, malaria has always been a common threat in European past, with the last epidemic occurring in the Netherlands during the 1950s. In the United States, Malaria has been endemic in as much as 36 states until the 1940s. By 1949, the country was declared free of malaria as a significant public health problem, after more than 4,650,000 house DDT spray applications had been made.The World Health Organisation estimates 150,000 deaths annually "as a result of climate change", of which half are in the Asia-Pacific region. In April 2008, it reported that, as a result of increased temperatures, the number of malaria infections is expected to increase in the highland areas of Papua New Guinea.
Infectious disease vectors
With high confidence, Confalonieri et al. projected that climate change would continue to change the range of some infectious disease vectors. Vector-borne diseases are infections transmitted by the bite of infected arthropod species, such as mosquitoes, ticks, triatomine bugs, sandflies, and blackflies. There is some evidence of climate-change-related shifts in the distribution of tick vectors of disease, of some mosquito vectors in Europe and North America. Climate change has also been implicated in changes in the breeding and migration dates of several bird species. Several species of wild bird can act as carriers of human pathogens as well as of vectors of infectious agents.Dengue
With low confidence, Confalonieri et al. concluded that climate change would increase the number of people at risk of dengue. Dengue is the world's most important vector-borne viral disease. Several studies have reported associations between dengue and climate, however, these associations are not entirely consistent.Malaria
The spatial distribution, intensity of transmission, and seasonality of malaria is influenced by climate in Sub-saharan Africa. Rainfall can be a limiting factor for mosquito populations and there is some evidence of reductions in transmission associated with decadal decreases in rainfall. The effects of observed climate change on the geographical distribution of malaria and its transmission intensity in highland regions remains controversial. There is no clear evidence that malaria has been affected by climate change in South America or in continental regions of the Russian Federation. There is still much uncertainty about the potential impact of climate change on malaria at local and global scales.A paper by researchers from the University of Oxford and the University of Florida published in Nature in May 2010 concluded that claims that a warming climate has led to more widespread disease and death due to malaria are largely at odds with the evidence, and that "predictions of an intensification of malaria in a warmer world, based on extrapolated empirical relationships or biological mechanisms, must be set against a context of a century of warming that has seen marked global declines in the disease and a substantial weakening of the global correlation between malaria endemicity and climate."
Other infectious diseases
There is good evidence that diseases transmitted by rodents sometimes increase during heavy rainfall and flooding because of altered patterns of human-pathogen-rodent contact.Projections
With very high confidence, Confalonieri et al. concluded that climate change would have mixed effects on malaria. Malaria is a complex disease to model and all of the published models assessed by Confalonieri et al. had limited parametrization of some key factors. Parametrization is used in climate models because the resolution of models is insufficient to resolve some physical processes. Given this limitation, models assessed by Confalonieri et al. projected that, particularly in Africa, climate change would be associated with geographical expansions of the areas suitable for Plasmodium falciparum malaria in some regions, and contractions in other regions. Projections also suggested that some regions would experience a longer season of transmission. Projections suggested expansions in vector species that carry dengue for parts of Australia and New Zealand.Diarrhoeal diseases
With medium confidence, Confalonieri et al. concluded that climate change would increase the burden of diarrhoeal diseases. Childhood mortality due to diarrhoea in low-income countries, especially in Sub-Saharan Africa, remains high. This is despite improvements in care. Several studies have shown that transmission of enteric pathogens is higher during the rainy season. Some studies have found that higher temperature was strongly associated with increased episodes of diarrhoeal disease in adults and children in Peru. Campbell-Lendrum et al. projected that climate change would increase the burden of diarrhoeal diseases in low-income regions by approximately 2 to 5% in 2020.Ground-level ozone
With high confidence, Confalonieri et al. projected that climate change would increase cardio-respiratory morbidity and mortality associated with ground-level ozone. Ground-level ozone is both naturally occurring and is the primary constituent of urban smog. Ozone in smog is formed through chemical reactions involving nitrogen oxides and other compounds. The reaction is a photochemical reaction, meaning that it involves electromagnetic radiation, and occurs in the presence of bright sunshine and high temperatures. Exposure to elevated concentrations of ozone is associated with increased hospital admissions for pneumonia, chronic obstructive pulmonary disease, asthma, allergic rhinitis and other respiratory diseases, and with premature mortality.Background levels of ground-level ozone have risen since pre-industrial times because of increasing emissions of methane, carbon monoxide and nitrogen oxides. This trend is expected to continue into the mid-21st century.
Cold-waves
continue to be a problem in northern latitudes, where very low temperatures can be reached in a few hours and extend over long periods. Reductions in cold-deaths due to climate change are projected to be greater than increases in heat-related deaths in the UK.estimating an observed trend over that period of 1.87% global precipitation increase per century.
Direct effects of temperature rise
The most direct effect of climate change on humans might be the impacts of hotter temperatures themselves. Extreme high temperatures increase the number of people who die on a given day for many reasons: people with heart problems are vulnerable because one's cardiovascular system must work harder to keep the body cool during hot weather, heat exhaustion, and some respiratory problems increase. Global warming could mean more cardiovascular diseases, doctors warn. Higher air temperature also increase the concentration of ozone at ground level. In the lower atmosphere, ozone is a harmful pollutant. It damages lung tissues and causes problems for people with asthma and other lung diseases.Rising temperatures have two opposing direct effects on mortality: higher temperatures in winter reduce deaths from cold; higher temperatures in summer increase heat-related deaths. The net local impact of these two direct effects depends on the current climate in a particular area. Palutikof et al. calculate that in England and Wales for a 1 °C temperature rise the reduced deaths from cold outweigh the increased deaths from heat, resulting in a reduction in annual average mortality of 7000, while Keatinge et al. "suggest that any increases in mortality due to increased temperatures would be outweighed by much larger short term declines in cold related mortalities." Cold-related deaths are far more numerous than heat-related deaths in the United States, Europe, and almost all countries outside the tropics. During 1979–1999, a total of 3,829 deaths in the United States were associated with excessive heat due to weather conditions, while in that same period a total of 13,970 deaths were attributed to hypothermia. In Europe, mean annual heat related mortalities are 304 in north Finland, 445 in Athens, and 40 in London, while cold related mortalities are 2457, 2533, and 3129 respectively. According to Keatinge et al., "populations in Europe have adjusted successfully to mean summer temperatures ranging from 13.5°C to 24.1°C, and can be expected to adjust to global warming predicted for the next half century with little sustained increase in heat related mortality."
A government report shows decreased mortality due to recent warming and predicts increased mortality due to future warming in the United Kingdom. The 2003 European heat wave killed 22,000–35,000 people, based on normal mortality rates. Peter A. Stott from the Hadley Centre for Climate Prediction and Research estimated with 90% confidence that past human influence on climate was responsible for at least half the risk of the 2003 European summer heat-wave.
Children
In 2007, the American Academy of Pediatrics issued the policy statement Global Climate Change and Children's Health:On 2008-04-29, a UNICEF UK Report found that global warming is already reducing the quality of the world's most vulnerable children's lives and making it more difficult to meet the UN Millennium Development Goals. Global warming will reduce access to clean water and food supplies, particularly in Africa and Asia. Disasters, violence and disease are expected to be more frequent and intense, making the future of the world's poorest children more bleak.
Limits of human survivability
Some areas of the world would start to surpass the wet-bulb temperature limit of human survivability with global warming of about 6.7 °C while a warming of 11.7 °C would put half of the world's population in an uninhabitable environment. In practice, the survivable limit of global warming in these areas is probably lower and in practice, some areas may experience lethal wet-bulb temperatures even earlier, because this study conservatively projected the survival limit for persons who are out of the sun, in gale-force winds, doused with water, wearing no clothing, and not working.The combined effects of global warming may have particularly harsh effects on people and countries without the resources to mitigate those effects. This may slow economic development and poverty reduction, and make it harder to achieve the Millennium Development Goals.
In October 2004 the Working Group on Climate Change and Development, a coalition of development and environment NGOs, issued a report: Up in Smoke. on the effects of climate change on development. This report, and the July 2005 report: Africa - Up in Smoke? predicted increased hunger and disease due to decreased rainfall and severe weather events, particularly in Africa. These are likely to have severe impacts on development for those affected.
In a literature assessment, Yohe et al. concluded that climate change would very likely make it more difficult for nations to achieve the MDGs for the middle of the century. In the short-term, it was judged very likely that climate change would not be a significant extra impediment to nations reaching their 2015 Millennium Development Targets.