The term global warming is often used synonymously with the term climate change, but the two terms have distinct meanings. Global warming refers to climate change where the increase in average temperature gradually warms the Earth’s atmosphere. Global warming is the combined result of anthropogenic emissions of greenhouse gases and changes in solar irradiation, while climate change refers to changes caused by global warming in weather (temperatures, precipitation, frequency of heat waves, etc.) and other climate system components, such as Arctic sea ice extent. Climate change is any substantial change in Earth’s climate that lasts for an extended period of time. The following points illustrate the implications of a rise in the Earth’s average temperate due to global warming.
Rise in Sea Level
The IPCC scientists have confirmed that the sea level worldwide rose between 10-25cm during the 20th century. As temperatures increase it is predicted that glaciers and polar caps will keep on melting making the sea level higher. Low-lying Pacific nations may be entirely flooded under the ocean. An important role of the polar caps is also to reflect the sun light. If our polar caps keep melting, it would add more heat to our oceans and land instead of helping regulate it. Because of the increasing temperature of oceans, plants and animals which aren’t heat tolerant would die.
Effect on Species
All plants and animals survive best within a particular temperature range. Global warming will change the temperature range affecting all biological species. Accordingly, species will slowly shift towards the poles or at higher altitude to evade higher temperatures. Large scale variation in temperature could see the loss of many trees and the area may be occupied by shrubs. Many animals and bird species, which are not able to track fast the temperature change and to migrate from there, will become extinct.
Pure rain water is neither acidic nor alkaline, it is neutral. However because of the presence of carbon dioxide in the atmosphere the rain water that we obtain on the earth is slightly acidic due to the formation of carbonic acid. In recent years it has been found that acidity of the soil has been increasing and ground water is becoming more and more acidic. This is due to the acid rain phenomenon. Acid rain directly effects the vegetation, both at the germination and flowering stages. It also affects buildings and architecture particularly made of marble. It pollutes ground water. The polluted water when consumed by humans causes respiratory, nervous and digestive disorders.
The layer of the earth’s atmosphere that surrounds us is called the troposphere. It extends up to 10km from Earth’s surface. The next higher layer, the stratosphere, extends about 10-15 kilometers above the earth’s surface. A layer of ozone (O3) is found between 15 and 35 kilometers in the stratosphere. Maximum concentration of ozone occurs at a distance of 25km. Now what is the role of this ozone layer around the earth in the stratosphere? It absorbs high frequency, low wavelength ultraviolet radiations coming from the sun and does not let them reach the Earth. The high energy ultraviolet rays are injurious to human and animal life. These rays cause skin cancer.
Scientists discovered in 1985 that the ozone layer was thinning over Antarctica. The thinning of ozone layer is termed as the ozone hole. It poses a serious environmental problem because a thin ozone layer cannot completely absorb the ultraviolet rays. If the ultraviolet rays reach the earth, they are sure to cause havoc to human and animal health in the form skin cancer, cataracts and weak immune system. A major culprit in the formation of the ozone hole is chlorofluorocarbons which are used in refrigerators and air conditioners. Jet planes and space rockets fired from the earth for various purposes also contribute to the destruction of ozone layer.
With the increase Carbon Dioxide concentration, the process of photosynthesis will get accelerated. But food production is likely to be lower because of other negative factors. It might also bring droughts to some areas where we presently grow crops. Inland lakes and rivers could shrivel crops and woodlands many also be afflicted by insects and plant disease. It is estimated that for each 10C rise in temperature, the rice production in South East Asia will decrease by 5 per cent. It also effects plants and animals leading to extinction of different species.
Ecological systems maintain relationships between organisms and their environment. Climate change may alter the world’s habitats and ecosystems. If the climate change occurred gradually, plants and living creatures may adapt to the new environment or move somewhere else. However, if the climate changes rapidly, scientists predict that the living plants and animals would become extinct because they will not be able to adapt quickly enough.
In a warm regions, scientists forecast more people get heat stressed, sicken or die, due heat. Ailments now found only in the tropics, spread by animals especially mosquitoes and other insects, will become more familiar in cooler areas as these animals widen their range and travel into regions too cold for them at present.