What are the impacts of climate on human health?

Global warming not only affects the environment, water resources, regional sea level rise, agriculture, natural vegetation and so on. And it also has a great impact on human health: the extension of hot summer weather and high temperature and humidity weather directly threatens people in mid-latitude areas sensitive to global warming; Global warming provides a better breeding ground for the propagation and spread of many pathogens, which will spread many infectious diseases from tropical and subtropical areas to the north and south, increase the number of threatened people and prolong the epidemic time.

Extreme high temperature mortality rate rises. The direct impact of climate change on human beings is the thermal effect caused by extreme high temperature, and children, the elderly, the infirm and patients with chronic diseases such as respiratory system, cardiovascular and cerebrovascular diseases are most affected. Thermal stress makes the thermoregulatory system in an "overload" state, which increases the load of damaged systems, tissues and organs, makes them ineffective, and often aggravates or even dies.

Continued high temperature will also cause heatstroke, which will suddenly increase the number of people suffering from "air conditioning disease", intestinal diseases, cardiovascular and cerebrovascular diseases, and there will be cases in which the elderly and patients die of heatstroke.

The spread of insect-borne infectious diseases has intensified. Another serious impact of climate warming on human health is the spread and recovery of some infectious diseases. At present, the three epidemic trends of insect-borne infectious diseases are: new diseases are constantly being discovered, the original epidemic areas are constantly expanding, and the epidemic frequency of diseases is constantly increasing. The continuous warming of the climate creates suitable conditions for the parasitism, reproduction and spread of insect vectors and pathogens, expands the epidemic scope, deepens the epidemic degree, causes changes in the distribution of diseases, and will aggravate the harm to people.

In addition, extreme weather and climate events such as hurricanes and floods caused by climate warming will trigger some insect-borne diseases. Among the most climate-sensitive infectious diseases, the incidence of mosquito-borne diseases including malaria, dengue fever and viral encephalitis will increase. The rising sea level and sea surface temperature caused by climate change will lead to an increase in the incidence of water-borne infectious diseases and toxin-related diseases. The deadly cholera outbreak in South America caused by 199 1 year proved this point.

Malnutrition and extreme events have intensified. There are obvious regional differences in agricultural output caused by climate change, which will aggravate malnutrition in some areas.

At present, there are 800 million malnourished people in the world. With the increase of the world population and the economic income of some countries, the grain consumption will double in the next 30 to 40 years. Hunger and malnutrition lead to decreased immunity and increase people's susceptibility to diseases. Malnutrition is the most important single pathogenic factor in the world. 1990 Nearly 6 million people died of malnutrition, twice as much as that caused by smoking.

Climate warming has increased many diseases. Climate warming can increase the concentration of some harmful substances in the air, such as fungal spores, pollen and atmospheric particles, with the increase of temperature and humidity, and increase the incidence of allergic diseases (such as hay fever and allergic asthma) and other respiratory diseases in the population; Climate warming can indirectly affect human health by affecting soil, plant photosynthesis and insect pests; Krypton chlorohydrocarbon is the main greenhouse gas, which has a destructive effect on the ozone layer, leading to an increase in ultraviolet radiation in sunlight, which may increase the incidence of skin cancer, cataract and snow blindness. Climate change will also worsen air pollution, and the incidence of allergies, cardiopulmonary abnormalities and deaths caused by air pollutants will increase accordingly.