What is the impact of global climate change on human health ?
person because of their social organization and the development of culture is better protected from exposure to environmental stress as compared to many plants and animals.Therefore, we tend to tolerate to global warming than other living beings.But in the end we feel it.The gases that cause the greenhouse effect and depletion of the ozone layer, already considered in the context of health and called biopolitical terror against the people of the whole world.
As the study of global warming is a very young branch of science dedicated to building weather prediction models, but not the actual study of human health, it is impossible to say with certainty what impact global warming on human health.Nevertheless, health and climate difficult interconnected, so here is acceptable preventive approach.
Our health depends on
climate caused by weather mortality increases when the temperature reaches its upper or lower limits.Ideal for human ambient temperature is in the range of 3 to 25 C. History shows that heat waves (thermal waves) took place about once every 310 years.Now scientists predict that their frequency will increase and they will occur every 5-6 years.
Small local increase in average temperature can cause a significant increase in the number of extremely hot days, which will increase the likelihood of deadly heat in the warmer months.In a temperate climate with an average summer temperature increase of 2-3 ° C over the number of hot days will increase by about half.
related to climate change more frequent heat waves will lead to more heat-related illnesses and deaths.As suggested by 2020 year mortality increase significantly (also expected to rise and winter mortality, but on a smaller scale).It is still not clear whether the excess summer mortality compensation for the reduction in mortality during periods of extreme cold.
combination of higher solar activity with an increase in the proportion of UV reaching the Earth's surface (due to the influence of the gases that cause the greenhouse effect and depletion of the ozone layer), can also lead to an increase in the incidence of skin cancer.If you do not take measures to control the emission of harmful substances into the environment, the level of air pollution by the year 2100 will increase by 4 times.This will turn the skin cancer from a relatively rare disease that occurs due to our own bad habits, in an important public health problem.
As the average global temperature of the Earth surface, we will increasingly suffer the extremes of weather.Because a higher temperature accelerates the water cycle - ascend into the atmosphere, and condensing, in turn precipitation (e.g., rain, fog, snow) process in which water vapor (mostly from the ocean surface).As the heat increases the rate of evaporation of the oceans.Warm air contains more moisture than cold, as well as the excessive moisture condensation increases the likelihood of heavy rain showers.
highest probability of precipitation will be in the middle and high latitudes.In the US since 1970, precipitation was on average 5% more than in the previous period.Over the past century rainfall in the colder seasons increased by almost 10%.In the northern part of Canada for the period of 1950-1990 years of the annual snowfall has increased by almost 20%, in Alaska, the figure was 11%.Observations over the past 100 years have shown that in the United States the incidence of extreme rainfall norms excess (more than 5 cm per 24 hours) has increased by about 20%.
What effect will an increase in precipitation?
Exceeding standards precipitation indicates an increase in the risk of flooding.Floods are dangerous for human health for many reasons.For example, when flooding can increase population of viruses and bacteria in an aqueous medium.Water can wash the gutters and other sources of pathogens (such as Cryptosporidium) and contaminate drinking water sources.It can be washed from the land fertilizer, which again fall into drinking water.Fertilizers and sewage, getting together in warm water, given the rapid algae bloom.Smells of some of them are toxic to humans, other algae poison fish and shellfish.Consuming such fish, you can buy a variety of diseases.In addition, algae bloom are carriers of Vibrio cholerae - organisms that cause cholera.Flooding also increases the risk of contracting dengue fever and infections carried by mosquitoes: malaria and Rift Valley fever (enzootic hepatitis, similar to the flu, which can be fatal for both cattle and humans).
Climate change can cover entire regions and affect the breeding periods of disease vectors, such as insects, rodents and snails.This development looks fantastic, but it is gradually becoming a reality.In New York, encephalitis outbreak in summer 1999 claimed three lives, cope with it quickly by spraying pesticides.Center for Disease Control has identified the cause of the infection - West Nile virus, carried by insects from sick birds.The peak of the disease, not previously encountered in the hemisphere, in temperate regions is at the end of summer - early autumn, and all year round may occur more mild climate.
changing climate, increasing disease
Recent studies have shown a 60% increase in the number of cases of plague in humans in the state of New Mexico after a wetter than normal winter and spring.Since the 1940 plague only once covered New Mexico.Significantly more frequent reports of cases of plague in the 1970s and 1980s were associated with wetter-than-normal weather conditions.
And in Sweden the spread of tick-borne (viral), encephalitis may be due to warmer winters, observed over the past two decades.There is some evidence that malaria at high latitudes in the highlands of East Africa, has spread due to local climate warming.
Simultaneously with the increase in the probability of heavy precipitation in winter increasing temperature also increases the draining soil and vegetation due to increased evaporation in summer.This can lead to more serious and extensive drought.
Already there was a slight decrease in rainfall in some regions, particularly in Africa, the Caribbean and tropical Asia.But definitely the high northern latitudes are at increased risk of exposure to the greenhouse effect.Decreasing snow cover and temperature rise in these regions will lead to early drying of the soil in the spring and increase the probability of drought.
Rising temperatures may also exacerbate the difference in atmospheric pressure over land and water, which will lead to gusty winds, tornadoes, and other forms of strong winds.In addition, the changing pressure and temperature changes that accompany global warming, can cause storms, floods and drought in the regions that were not previously exposed to these phenomena.