Climate change: its harmful effects on health
The increase in temperature in the atmosphere is more specifically known as global warming. But climate change is the term currently preferred by scientists, since it explicitly includes not only the increase in the Earth’s global average temperature, but also the climatic effects caused by this increase.
Any gas that has the property of absorbing infrared radiation emitted from the Earth’s surface and re-radiating it towards the Earth’s surface is called a greenhouse gas. Carbon dioxide, methane and water vapor are the most important greenhouse gases. Other greenhouse gases include, but are not limited to, surface ozone, nitrous oxide, sulfur hexafluoride, hydrofluorocarbons, perfluorocarbons, and chlorofluorocarbons.
Although it is a natural phenomenon, the greenhouse effect produces a warming of the earth’s surface and the troposphere, the lowest layer of the atmosphere. Of the greenhouse gases, water vapor has the greatest effect.
Some major causes of the greenhouse effect include the burning of fossil fuels such as coal, oil, and natural gas, deforestation, population growth, agriculture, and industrial waste and landfills.
Greenhouse gases trap heat in the atmosphere. With higher than normal concentrations, they lead to unnatural heating. The main cause of the current global warming trend is the human expansion of the greenhouse effect, a warming that occurs when the atmosphere traps heat radiating from the Earth into space.
Even a small increase in global temperature could have worrying consequences such as rising sea levels, population displacement, food supply disruption, flooding, and adverse health effects. In fact, human health bears the brunt of the consequences of climate change.
Harmful effects of climate change on health –
Climate change can affect human health in two main ways: first, by changing the severity or frequency of health problems that are already affected by climatic factors, and second, by creating health problems in places where they did not occur before. previously.
Effects of temperature rise –
The increase in greenhouse gas concentrations leads to an increase in both average and extreme temperatures. This can compromise the body’s ability to regulate its temperature. Loss of core temperature regulation can result in a cascade of illnesses, including heat cramps, heat exhaustion, heat stroke, and hyperthermia in the presence of extreme heat, and hypothermia and frostbite in the presence of extreme cold. Extreme temperatures can also worsen chronic conditions, such as diabetes-related illness, respiratory disease, cerebrovascular disease, and cardiovascular disease.
People who work outdoors, are socially isolated, economically disadvantaged and those with chronic illnesses are more vulnerable to the impact of rising temperatures.
Effects of air quality –
Climate change has altered weather patterns, which in turn has influenced the levels and location of outdoor air pollutants such as tropospheric ozone (O3) and fine particulate matter. Increased levels of carbon dioxide (CO2) also promote the growth of plants that release allergens into the air. Higher pollen counts and longer pollen seasons can increase allergic sensitization and asthma episodes, limiting productivity at work and school. Poor air quality, whether indoors or outdoors, can negatively affect the human respiratory and cardiovascular systems.
Effects of extreme events –
Climate change causes an increase in the occurrence and severity of some extreme events, which can have health impacts such as deaths or injuries during an event, for example, drowning during floods. Health impacts can also occur before and after an extreme event, as people involved in activities such as disaster preparedness and post-event cleanup put their health at risk. The severity and extent of health effects associated with extreme events depend on the physical impacts of the extreme events themselves.
Vector-borne diseases –
Vector-borne diseases are transmitted by vectors, which include mosquitoes, ticks and fleas. These vectors can carry infectious pathogens such as viruses, bacteria, and protozoa, which can be transferred from one host (carrier) to another. The seasonality, distribution and prevalence of vector-borne diseases are significantly influenced by climate. Climate change is likely to have both short- and long-term effects on vector-borne disease transmission and infection patterns, affecting both seasonal risk and disease occurrence over decades.
Water-related diseases –
Climate change is expected to affect freshwater and marine resources in ways that increase people’s exposure to water-related contaminants that cause disease. Water-related diseases include waterborne diseases caused by pathogens such as bacteria, viruses, and protozoa. Water-related illnesses are also caused by toxins produced by certain harmful algae and by chemicals that human activities introduce into water sources. Exposure occurs through ingestion, direct contact with contaminated drinking or recreational water, and through consumption of contaminated fish and shellfish.
Effects on mental health –
Mental health consequences of climate change range from minimal symptoms of stress and distress to clinical disorders such as anxiety, depression, post-traumatic stress and suicidality. Children, the elderly, women (especially pregnant and postpartum women), people with pre-existing mental illnesses, the economically disadvantaged, and the homeless are more exposed to its mental health consequences.
Effects on food safety and quality –
Climate change is very likely to affect food security at the global, regional and local levels by disrupting the availability of food, reducing access to food and hindering its utilization. Higher CO2 concentrations can reduce levels of essential proteins and minerals in a number of widely consumed crops, including wheat, rice and potatoes, with potentially negative implications for human nutrition. Poor nutritional quality of food is more likely to negatively affect vulnerable sectors of the population.
The bottom line –
Over the past 50 years, human activities have released sufficient amounts of carbon dioxide and other greenhouse gases to trap additional heat in the lower atmosphere and affect global climate. According to the WHO (World Health Organization):
- Climate change affects the social and environmental determinants of health: clean air, safe drinking water, enough food, and safe housing.
- Between 2030 and 2050, climate change is expected to cause an estimated 250,000 additional deaths per year, from malnutrition, malaria, diarrhea and heat stress.
Therefore, in view of the serious repercussions of climate change on human health, we must all make concerted efforts to reduce greenhouse gas emissions through better transportation, food and energy use options to improve our health. , in particular by reducing air pollution.