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Health impacts of climate change

Climate change is a major problem caused by the increase of human activities leading to several direct and indirect impacts on health. The combustion of fossil fuels, increasing number of industries, and large-scale deforestation are some of the causes for the accumulation of GHGs (greenhouse gases) in the atmosphere. According to the IPCC (Intergovernmental Panel on Climate Change), an increase in carbon dioxide and other GHGs, like methane, ozone, nitrous oxide, and chlorofluorocarbons, in the atmosphere is expected to increase the average global temperature by 1.5 C to 4.5 C. This in turn will lead to changes in rainfall and snowfall, more intense or frequent droughts, floods, and storms, as well as a rise in sea level. These climatic changes will have wide-ranging harmful effects including increase in heat-related mortality, dehydration, spread of infectious diseases, malnutrition, and damage to public health infrastructure. Thus we should take appropriate measures to stop this climate change.

Direct impacts

The weather has a direct impact on our health. If the overall climate becomes warmer, there will be an increase in health problems. It is anticipated that there will be an increase in the number of deaths due to greater frequency and severity of heat waves and other extreme weather events. The elderly, the very young and those suffering from respiratory and cardiovascular disorders will probably be affected by such weather extremes as they have lesser coping capacity. An extreme rise in the temperature will affect people living in the urban areas more than those in the rural areas. This is due to the ‘heat islands’ that develop here owing to the presence of concrete constructions, paved and tarred roads. Higher temperatures in the cities would lead to an increase in the ground-level concentration of ozone thereby increasing air pollution problems.

Indirect impacts

Indirectly, changes in weather pattern, can lead to ecological disturbances, changes in food production levels, increase in the distribution of malaria, and other vector-borne diseases. Fluctuation in the climate especially in the temperature, precipitation, and humidity can influence biological organisms and the processes linked to the spread of infectious diseases.

Higher temperature will cause the sea levels to rise that could lead to erosion and damage to important ecosystems such as wetlands and coral reefs. Direct impact of this rise would include deaths and injury caused by intense flooding. Temperature rise would indirectly result in geohydrological changes along the coastline such as saltwater intrusion into the groundwater and the wetlands, coral reef destruction, and damage to the drainage in the low-lying areas. Climate change could increase air pollution levels by accelerating the atmospheric chemical reactions that produce photochemical oxidants due to a rise in the temperature.


The GHGs have been responsible for the depletion of stratospheric ozone, which protects the earth from the harmful direct rays of the sun. Depletion of stratospheric ozone results in higher exposure to ultra violet rays of the sun, leading to an increase in the incidents of skin cancer in light skinned people. It could also lead to an increase in the number of people suffering from eye diseases such as cataract. It is also thought to cause suppression of the immune system.

Due to global warming there will be an increase in the areas of habitat of disease-spreading insects such as the mosquito, causing an increase in the transmission of infection through these carriers.

Potential effects on health due to sea level rise include:
sqb.gif (46 bytes)death and injury due to flooding;
sqb.gif (46 bytes)reduced availability of fresh water due to saltwater intrusion;
sqb.gif (46 bytes)contamination of water supply through pollutants from submerged waste dumps;
sqb.gif (46 bytes)change in the distribution of disease-spreading insects;
sqb.gif (46 bytes)effect on the nutrition due to a loss in agriculture land and changes in fish catch; and
sqb.gif (46 bytes)health impacts associated with population displacement.

Preventive measures

sqb.gif (46 bytes)Reduction in the use of non-renewable sources of energy and increased use of renewable sources will undoubtedly decrease the emission of GHGs substantially. This decrease in the GHGs will have a positive affect on the health and well being of the people.
sqb.gif (46 bytes)Furthermore, switching to cleaner fuels and energy-efficient technologies will reduce local pollutants and therefore, have an added beneficial impact on health.