Even before the industrial revolution,there were changes in the Earth’s temperature, but now the changes are much more rapid and severe.The main reason for this is pollution.Gases like methane, carbon dioxide, carbon monoxide, chloroflourocarbon[CFC'S],nitrogen oxides, hydroden peroxide,and others absorb the heat from the Sun. Due to this, the temperature of the earth goes up and changes occur in the climatic conditions. This is what is called as the greenhouse effect.Fossil fuels like coal, kerosene,petrol,diesel ,when burnt release carbondioxide. Incompletely burnt fuels release carbondioxide.Methane is released from decining organic matter, wet waste and rice fields.
Due to the greenhouse effect, temperature all over the world is rising. Ice near the poles is melting pushing up the sea level. Low- lying coastal areas like Maldives and Bangladesh may submerge into the sea.
Carbon is found in all living and non-livingthings . During respiration,humans animals and all life forms breathe in oxygenand release carbondioxide. We all knowthat trees absorb carbondioxide and release oxygen in the daytime and they absorb oxygen and release carbondioxide during night.Since, the trees and forests are being cut down oxizen is getting scarce but carbondioxide in the air is increasing. Further more,in cities and villages,fallen leaves are burnt,causing the release of carbon gases, adding to the green house effect.We can thus see that the burning of anything on the Earth releases green house gases like carbondioxide into the atmosphere.
With the release of the greenhouse gases ,theEarth gets heated up.This also has a severe impact on agriculture.Due to green house effect the temperature rises increasing the evaporation.The land loses its moisture .Insects,pests and weeds in the farms multiply faster.The soil loses its fertility faster.Increased photosynthesis can lead to higher crop yields but crops may need more water.Availability of carbondioxide may quicken the harvesting process and increase crop output .But persisting high temperatures even during winter may cut down the yield of cereals and fruits due to the reduction in moisture.
Reduction in time between sowing and reaping may lead to reduced crop production.Increased rate of evaporation due to the rise in temperature may lead to increased rainfall as well as to greater humidity in the air.These climatic conditions favour growth of fungus,micro organisms and pests and they can cause severe crop losses.On the hand sudden rise and fall of temperatures would lead to repeated droughts and floods that can destroy vast areas of farmland.The Kyoto Protocal was signed specifically to avoid the above situation.According to this,all countries across the world will have to gradually limit emision of greenhouse gases.As the initial step, however,the countries have to plant trees that absorb these gases so as to reduce their effect.
The effects of ozone depletion and green house gaseses is being felt allover the world.Thus ,a world wide effort is required to tackle the problems.In 1992,the nations of the world signed a ClimaticChange agreement in Rio de janerio.According to this agreement, all nations of the world have agreed to do what they can to reduce their emissions of the greenhouse gasesand ozone depleting substances.To acheive this ,there should be a cut in the use of fossils fuels and of appliances that affect the ozone layer.If we don’t change our lifestyle we can’t escapethe effects of greenhouse gases,can’t stop the destruction of the ozone layer and we cannot stop acid rains.
