Global warming: A disaster of our own making [Archives:2007/1038/Health]
By: Udal Ram
B.Tech (Petroleum Eng.)
Asst. GM (Drilling), CCOGC
For Yemen Times
The sun is Earth's ultimate energy source. In fact, energy from the sun is the reason most living organisms exist and prosper.
The earth receives energy from the sun in the form of radiation. After reaching Earth's atmosphere, 30 percent of this energy is radiated back into space, with the atmosphere absorbing approximately 20 percent. The remaining 50 percent of energy reaches Earth's surface and out of this, plants, soil and oceans absorb 85 percent of this heat energy, while the rest is reflected back into the atmosphere.
Greenhouse gases and the greenhouse effect
Certain gases in the atmosphere retain and trap heat emitted from Earth's surface. The gases that help trap this heat energy are called greenhouse gases. Greenhouse gases absorb this energy and warm the atmosphere. This is a natural phenomenon described as the greenhouse effect.
Without this natural greenhouse effect, heat energy absorbed and reflected from the earth would be lost to space. This would lower Earth's temperature to approximately -18 C and it would be impossible for most living organisms to survive at this low temperature. Thus, this effect provides a thermal insulation blanket warming the earth's surface.
Greenhouse gases are atmospheric components that contribute to the greenhouse effect. Most gases contributing to this effect occur naturally in the atmosphere, while others are produced from human activities.
The most abundant natural greenhouse gas is water vapor, followed by carbon dioxide, methane, nitrous oxide, ozone and chlorofluorocarbons (CFCs), which contribute more than 98 percent to the greenhouse effect. Increased agriculture, deforestation, industrial manufacturing and mining further contribute to greenhouse gas emissions.
Greenhouse gas emissions
Carbon dioxide is the primary greenhouse gas emitted by human activities. It is released into the atmosphere when fossil fuels like oil, coal, natural gas, solid wastes, wood and wood products are burned. Deforestation also releases stored carbon, which reduces the natural “carbon sink.”
Methane is a byproduct of production and transportation of oil, natural gas and coal. It also is produced from decomposing organic waste and livestock. Nitrous oxide is released during agricultural and industrial activities, as well as during combustion of solid waste and fossil fuels. Other greenhouse gases are added to our atmosphere due to various industrial processes.
Numerous factors, including governmental policies, social and economic development, the changing pattern of global technology and new innovations, will determine future carbon dioxide emissions and concentrations in the atmosphere. It has been projected that by 2100, atmospheric carbon dioxide levels will be between 30 percent and 150 percent higher than current levels.
The role of fossil fuels
It's a well-established fact that energy-related activities are responsible for nearly all carbon dioxide emissions in major parts of the world. Research has proven that fossil fuel combustion is primarily responsible for contributing to carbon dioxide emissions. Coal produces the largest amount of carbon dioxide, followed by petroleum and natural gas.
Global warming
The past two decades have witnessed rapid urbanization and industrialization leading to steep fossil fuel consumption in many parts of the world. Along with the changing pattern of land use, this is resulting in more and more carbon being dumped into the atmosphere, thus altering the natural process that maintains Earth's surface temperatures. The vast pouring of carbon into the atmosphere has disturbed the equilibrium of the natural balance of carbon in the earth, oceans and atmosphere.
Burning fossil fuels releases more than 5.5 billion tons (BT) of carbon annually while changing patterns of land use worldwide contribute another 1.5 billion tons per year, resulting in more than seven billion tons of carbon released every year.
The ocean absorbs approximately two BT annually and the terrestrial biosphere another two BT per year, yet more than three BT of carbon remains to accumulate yearly in the atmosphere. This has adversely affected the ecological system's natural capacity to adjust carbon levels. As more and more carbon accumulates in the earth's atmosphere, more and more heat is trapped, which ultimately raises the earth's temperature.
This unnatural warming of the earth is known as global warming. Environmental researchers forecast an estimated 1.4-5.8 degrees Celsius increase in Earth's surface temperature over the next 100 years. This will damage the earth's ecological system, as well as negatively affect social, economic and administrative systems globally, especially in those developing countries with minimal resources.
Changing climate
If we continue to keep our eyes shut, Earth will become a garbage tip as increasing greenhouse gas concentrations are projected to accelerate the rate of global climate change. Global warming will lead to unimaginable disasters that won't spare anyone. Whoever causes the damage, all will share the consequences of this manmade catastrophe. Climatic change won't be uniform across the globe, but it eventually will encompass every society and culture. We've already witnessed the 10 hottest years during the last 15 years of the 20th century.
As a consequence of global warming, extreme weather events, including severe droughts and heavy rains, have increased in intensity and are projected to increase in frequency, which will lead to long-term effects on human health. This has become a serious concern for everyone worldwide. Changes in the intensity and frequency of weather extremes will most profoundly impact agriculture, social infrastructures, economies, ecosystems and human health.
Human health impacts
Global warming will lead to global climate change, which will have multiple overall negative impacts on human health. Prolonged droughts already have drastically reduced food production and contributed to population displacement. In the past decade, intense flooding has caused economic disaster in many parts of the world.
Many variables will determine the magnitude of the impacts on human health due to global warming. Social factors, including poverty, poor nutritional status and overcrowding, along with ecological changes, including deforestation and loss of coastal wetlands, will render many developing countries particularly vulnerable to extreme weather events and subsequent outbreaks of infectious diseases.
The direct health impacts of global warming include increases in heat-related mortality and morbidity from illnesses associated with heat waves and thermal stress, principally affecting the elderly and the urban poor. While warmer winters may decrease cold-related mortality in many temperate countries, increased temperature variability in summer and winter may have the greatest impacts on mortality. Extreme weather such as intense rainfall can lead to increased runoff and thus, exposure to chemicals, nutrients and microorganisms in water supplies, as well as physical damage, food shortages, population displacement and death. Community damage then can have psychological and economic impacts.
Severe weather systems also can create conditions conducive to clusters of infectious disease outbreaks because of flooding, standing water, water contamination and unavailability of fresh water, which will further increase mortality and morbidity.
The indirect effects of global warming on biological systems may be of even greater consequence for human health. Climate change due to global warming will create conducive conditions for transmission of carrier-borne infectious diseases like malaria, dengue fever and viral encephalitis. Heavy rains and flooding, as well as drought with inadequate water supplies and sanitation amenities, also are conducive to outbreaks of waterborne diseases.
Climate changes put additional pressure on world food supplies as agricultural productivity is severely affected by floods and droughts due to global warming. However, the negative impacts of this will be felt more severely in the developing world since this will add to the number of malnourished people in these regions, which is already home to the largest impoverished and vulnerable community. Hunger and malnutrition not only increase infant and child mortality, but also cause physical and intellectual stunting. Both severe weather events and gradual warming have the potential to cause social and economic disruption and population displacement. The ability of populations to contend with such events depends upon the nation's social, political and economic conditions.
It has been projected that sea levels will rise as much as 90 cm. due to global warming by the year 2100. Since more than half the world's population lives within 60 km. of the sea, rising seas could have devastating effects on coastal populations. If global warming continues unabated, many island nations will be extinct by the next century.
Rising sea levels also can affect food production and water due to excessive salination of fresh soil and water and thus, negatively impact public health.
Global Warming's educational relevance
Despite the growing evidence that global warming is a very real threat to human social systems, it has received relatively little relevance in media or the education system as a whole. Global warming is an issue that's more social than scientific in nature.
Because global warming is a global reality, it requires a pattern of global education focusing on ecology and the environment in general and global warming in particular. Therefore, students should be guided in class to view the global reality as a set of interrelated systems where individual decisions can't be separated from global welfare.
Hence, young minds should be encouraged and motivated to think about global warming's interconnectedness to humanity and how it affects the entire globe. In fact, the subject of global warming should be incorporated into a science and environment curriculum that will introduce students in a sensitive way to the world as a whole, which will give them insights into different geographical settings, cultural heritages and traditions. It will incite them to think about how global climate change due to global warming will affect the entire socioeconomic and cultural fabric of this planet.a
Such an environmental curriculum should be designed on a pattern of science and environmental study, which not only will infuse a sense of responsibility and awareness in the minds of young citizens around the globe about the current evils of environmental degradation, pollution and global warming, etc., but also will teach them the remedy and cure that science and technology will bring about for a better tomorrow.
Today, we're facing numerous challenges to the global future and global warming is one of the most devastating, presenting a sense of hopelessness to young minds in particular. This urgently requires educational dedication and commitment from all educators. The urgency of global connectivity by way of integrating environmental education highlighting global warming calls for global education.
Environmental education will facilitate new ways of looking at the world, as well as foster insight, understanding and sensitivity regarding humanity and the earth. This calls for a global education system infusing new global realities into teachers' education as well. This must be an ongoing process of defining and redefining ways to prepare youths for diversity, equity and interconnectedness in their own community, their region and the world.
The importance of educating young minds and creating social awareness about global warming among the masses is equally vital and directly related to the use of the mode of energy that directly or indirectly contributes to the phenomenon of global warming and climate change.
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