The world has witnessed significant changes in climatic trends that have resulted in overwhelming impacts. Global warming is one of the most serious impacts brought about by climate change. It is caused by the continued increase in the earth’s average temperatures particularly the air near its surface as well as those of the oceans (Archer, 2009 p.1).
The genesis of this phenomenon can be traced to the 1950’s with significant increases over the years. Climatologists have indicated that global warming is attributed greatly to the ever increasing levels of greenhouse gases which are emitted into the atmosphere during the day to day human activities.
The burning of fossil fuel as well as deforestation has been singled out as among the major activities that result in the increase of greenhouse gas concentration in the atmosphere (McMichael, 2003 p.8). Absence of vegetation and the burning of fossil fuel lead to increase in the concentration of carbon dioxide which in turn contributes to global warming.
The increasing global temperatures cause the level of water in the seas to rise due to the melting of sea ice and glaciers. This interferes with the pattern of precipitation. Moreover, greenhouse effect is experienced when the temperatures of the atmosphere and air near the earth’s surface increase as a result of absorption and emission of infrared radiation by atmospheric gases (McKinney & Schoch, 2003 p.430).
Some of the commonly known greenhouse gases include the carbon dioxide, water vapor, methane and the ozone. Global warming has numerous effects ranging from the effects on the physical, ecological to social or economic dimensions. This essay discusses the various effects of climate change on the health of human beings.
Human health is affected by global warming both directly and indirectly. While there are some benefits associated with global warming, the continued increase in the average global temperature has proved that negative consequences will increase while the advantages decrease significantly (Archer, 2009 p. 10).
People are at risk of being exposed to the negative consequences of global warming due to the change in the weather patterns. Increasing temperatures has direct influence on the physical environment as well as the human body. Change in precipitation pattern can cause increased rainfall, windstorms or drought in some areas. The rise in sea levels can cause floods and other extreme catastrophes. Furthermore, human health is affected indirectly by the changes in the quality of food consumed, air and water.
The impacts of climate change extend also to dramatic changes in agricultural production, settlement patterns and ecosystem in general (Dincer, Hepbasil & Midilli, 2009 p.424). These changes are responsible in affecting the human health either directly or indirectly. Some of the major effects of global warming on human health include; malnutrition, extreme catastrophes and spread of infectious diseases (Tennesen, 2004 p.44).
It has been established by health scientists that global warming is causing over 150,000 deaths and more than 5 million diseases every year (Archer, 2009 p.12). They also indicated that estimates could double by 2030.The changes in climate patterns result in inadequate food supply.
Drought, for instance, causes destruction of food crops leading to hunger among people and general food insecurity. The diet of that food that may be available is totally imbalanced contributing to malnutrition due to lack of essential nutrients. Health researchers have linked incidences of morbidity and mortality rates to climate change and that the impacts are felt very differently in various parts of world (Dincer et al., 2009 p.431).
Cases of malnutrition have been found to be high among people in low income countries who are already overwhelmed by the burden of diseases and higher death rates associated to increasing temperatures. Developed countries, on the other hand, are responsible for the continued climatic changes though they are yet to feel the real effects of global warming.
The spread of infectious diseases has been significantly associated with climate change. Changes in climate have resulted in different patterns of breeding and migration/distribution of disease vectors such as malarial mosquitoes and birds’ species capable of being carriers of human pathogens (Brown, 2002 p.51).
The different bird species can also be carriers of vectors of other infectious agents. Studies have shown that there is strong relationship between the intensity of transmission and pattern of occurrence of malaria and the climatic pattern in the sub-Saharan Africa. The risk of malaria infection, especially in Africa is due to the expansion of areas conducive for Plasmodium falciparum malaria.
Health scientists, however, are still trying to establish if there is clear connection between climate change and malaria infection. Dengue, the world’s most significant vector-borne viral disease presents a risk to many people due to continued climate change (Archer, 2009 p.14). The species of vectors responsible for the transmission of dengue fever have been projected to increase with global warming, particularly in most parts of Australia.
Use of contaminated drinking water is responsible for increased cases of diarrhea. Global warming has also been associated with increasing incidences of diarrheal diseases. In developing countries, mortality among children resulting from diarrhea has been on alarmingly high levels, particularly in Sub-Saharan Africa. In South America, cases of diarrhea among adults as well as children have been associated with increasing temperatures.
During rainy seasons, enteric pathogens have been found to be highly transmitted (Brown, 2002 p.58). Global warming is also characterized by the UV radiation which can impact negatively on human immune system (McMichael, 2003 p.35). Failure of the immune system facilitates the spread of infectious diseases due lack of sufficient protection. It can also result in skin cancer and cause cataracts which impairs vision.
Extreme weather events linked to global warming have presented another great risk to human health and survival. Significantly high numbers of deaths and illnesses have been recorded due to such catastrophes as floods, heat waves, wild fires, droughts, and storms. Unpredictable flooding with far reaching damaging potential has been witnessed in some parts of the world, especially in America and Asia. Floods can destroy infrastructure and cause the displacement of thousands or millions of people (Tennesen, 2004 p.49).
Over the last twenty years, many people and property have been lost to large-scale floods and storms. Some of the survivors of such weather disasters have later on succumbed to water-borne diseases. Some studies have shown that the rate of domestic violence against women increases with each natural disaster. Furthermore, higher incidences of post-traumatic stress disorder occur among women. Tropical cyclones and floods have caused numerous deaths and other health impacts in Latin America and South Asia.
Health problems associated with floods and other weather disasters are heavily felt in densely populated and low-lying coastal regions of the world. Global warming has also resulted in hotter days, hot nights as well as heat waves which are closely linked to the period increases in mortality rates (Archer, 2009 p.106). Heat waves are mostly experienced in the United States and Europe and have always resulted in excess mortality of up to 35,000 deaths annually in Europe alone.
In the United States, records indicate that more annual deaths are caused by heat waves which are more than those by tornadoes, hurricanes, floods and earthquakes combined. If the trend of global warming over the past 12 years continues, heat waves will result in increased cases of heat stroke as well as other heat-related deaths. Apart from causing deaths from hunger, malnutrition, and speeding the spread of infectious diseases, drought due to global warming causes the increase in respiratory diseases.
Semi-arid and Sub-Saharan regions of Africa have been known to be prone to meningococcal meningitis. As the global temperatures increases, the level of air pollution increases accordingly. This aerial pollution has caused a significant increase in respiratory and cardiovascular diseases, which include asthma and cardiac disarrythmia (Tennesen, 2004 p.52). Ground-level ozone is expected to increase in some cities of the United States as climate change continues to occur.
The ever rising global heat levels is usually the cause of wildfires which destroy homes, kill people and their livelihoods as well as air pollution(McMichael, 2003 p.165). Wildfires have been known to occur mainly in drought stricken areas. In the United States, people in states like California which may experience prolonged summer periods are likely to be displaced due to the risk of wildfires.
The essay has explored the various effects of global warming on human health. It is evident that climate change has numerous impacts on human existence which can either be direct or indirect. Some of the effects identified include; drought, floods, wildfires, heat waves, and resultant effects such as infectious diseases like malaria and dengue, diarrhea, malnutrition, post-traumatic stress disorders, immune failure, and respiratory and cardiovascular diseases.
Weather disasters have also been known to cause instant deaths. Environmental scientists have established that these consequences will continue to increase as long as the various human activities contributing to climate change continue to be practiced. Appropriate measures, therefore, need to be taken in order to mitigate the disastrous effects of global warming on human health.
References
Archer, D. (2009) The long thaw: how humans are changing the next 100,000 years of earth’s climate. Princeton University Press, pp. 1-158
Brown, D. A. (2002) American heat: ethical problems with the United States’ response to global warming. Rowman & Littlefield, pp. 49-61
Dincer, I., Hepbasil, A., & Midilli, A. (2009) Global warming: engineering solutions. Springer, pp. 424-38
McKinney, M. L. & Schoch, R. M (2003) Environmental Science: systems and solutions (3rd ed.). Jones & Bartlett Learning, pp. 430-42
McMichael, A. J. (2003) Climate change and human health: risks and responses (2nd ed.).World Health Organization, pp. 8-175
Tennesen, M. (2004) The complete idiot’s guide to global warming. Alpha Books, pp. 44-53