Global Warming denotes the increase in the earth’s surface temperature caused by emission of carbon dioxide from burning fossil fuels coupled with massive deforestation. Concentration of carbon dioxide in the atmosphere is correlated with the combustion of fossil fuels for generation of electricity, transportation and manufacture of cement. The greenhouse effect results in annual emission of 22 billion tons of carbon dioxide to the atmosphere.
The studies and surveys conducted all over the world clearly establish a discernible rise in average temperature since 1900. In fact, the process of global warming actually started with deforestation in the forested part of Northeastern America in 1800 followed by industrial revolution.
Impact of global warming is felt in numerous forms such as inundation of low-lying cities and islands, droughts, fires and climatic changes in some areas, loss of habitat near the poles, melting of old glaciers, damage of coral reefs due to warming seas and acidification, loss of population of sea lions and fish.
If we do not significantly curb our use of fossil fuels, the amount of carbon released by it will soon exceed the amount of carbon in the living biosphere. Investigations are being carried out to find out ways and means to offset global warming but no foolproof method has yet been evolved. The U.S.A alone needs to cut back its annual emissions by around 500 million tons of carbon dioxide.
Renewable energy is a good substitute for fossil fuels. However, many new programs are laying stress on capturing the extra carbon dioxide from electricity generation plants and sequestering it in the ground and the ocean. The developed countries are also toying with the idea of stimulating the Earth’s ecosystems to absorb more carbon dioxide. Another idea is to pump carbon dioxide into old oil and gas wells.
Pollution is the process of contamination of a natural environment, making air, water and land unsafe and unhygienic. In the long run, it afflicts us with several diseases and lowers our life expectancy.
Land is predominantly polluted by household garbage and industrial waste. About half of the waste is dumped in the landfills and a little above one third is recycled. Household garbage consists of furniture, clothing, food scraps, bottles, batteries. The most hazardous items are paints, motor oil, aerosol cans and fluorescent lights. Industrial waste includes non-hazardous items such as wood, glass and concrete. However, chemicals that are generated from mines, oil refineries and pesticide manufacturers are hazardous.
Water pollution is caused by chemicals, pesticides, sewage, fertilizers, lead and mercury running into water from industrial plants. Apart from affecting human health, water pollution severely harms marine life. Thermal plants use water to cool its operation and discharge hot water. This reduces the capacity of water to hold oxygen and leads to death of fish and other marine animals.
Air pollution is caused by burning fuels, dangerous gases such as sulfur dioxide, carbon dioxide – which we also call greenhouse gases- along with carbon monoxide and chemical vapors. They pollute the atmosphere and affect our health in varying degrees by giving rise to the incidence of respiratory illness and cardiovascular diseases. According to a study published in “Environmental Research Letter”, more than 2 million people die every year due to air pollution.
Noise pollution causes high blood pressure, stress-related illnesses, speech interference and hearing loss. Noise produced by ships affects whales’ movement and kill marine species.
Even electric light, which is indispensable in modern life, has changed the ways in natural world by causing light pollution. Artificial light affects migration schedule of birds, confuse the sea turtles and disrupts plant’s flowering and developmental pattern.