BBC brought into the lime light the critical issue of Global Dimming by its documentary named Horizon on January 15, 2005. All of us know about Global Warming but few of us are aware of Global Dimming. Now the question is what is global dimming? Fossil fuels have remained one of the greatest sources of energy from ages. When these fuels are burned than not only green house gases but also by-products are produced. These by-products are comprised of a variety of pollutants like ash, soot and sulphur dioxide. These impurities are responsible for changing the properties of the clouds. Contrails, the vapors of the aircraft, also contribute in Global Dimming.
Note: Earth is not receiving enough of sunlight, hence producing the
These polluted particles result in increasing the number of droplets per cloud. The reflective property of these clouds thus increase. These clouds sent the rays of sun back into the space instead of letting it reach the surface of the earth. Global Dimming is the phenomenon when the number of heat waves reaching earth reduces.
The toxic residues that aggregate the issue of Global Dimming are also accountable for fog, acid rain and various respiratory diseases. Thus the impact is neither limited to humans nor to environment.
The affects of Global Dimming are tragic. It has already killed living beings on massive level. The reflecting back of heat has turned the water of northern hemisphere colder. With water’s temperature getting down less rain is generated and the required amount of rain is failed to reach The Sahel, Northern Africa. It is now disclosed that the complex famines of 1970s and 1980s were caused by the less number of rains. The BBC documentary concluded that the smoke coming out of power stations and pipes of North America and Europe is responsible for the death of millions of people in Africa while making the life of more than 50 million people miserable. It is estimated that billions of people in Asia will be affected by the Global Dimming. The monsoon rains of Asia provide rainfall to almost half of the world’s population. If Global Dimming will be able to decrease the number of rains then half of the world’s population (around three billion people) will be starving.
The positive aspect of Global Dimming is that it covers the drastic effects of Global Warming. It is predicted by the climate change models that the temperature of earth will increase by five degrees by the next century. The issue has currently under estimate the aftermath of Global Warming.
The most critical point in this discussion is the fact that if efforts are made to control Global Dimming than Global Warming will be in turn exposed. the rays of sun can be called back on earth by controlling the emission from industries but it will led to more and more Global Warming as the green house gases are available in abundance in the atmosphere. To enlighten you on the subject let us review the example of Europe in 2003. Europe made efforts to clean the atmosphere from pollutants without keeping in mind the excessive amount of green house gases. As a result, the number of toxic particles reduced where the amount of green house gases remained same. It no doubt decreased the intensity of feminine in Sahel by increasing the amount of rains but it also created the severe heat wave in 2003 that killed thousands of people in Portugal and France and struck the continent with a number of other issues.
Now let us suppose that we do not made effort to control Global Dimming to protect ourselves from Global Warming than the disaster of increasing Global Dimming will not be more than 30 years away. The sea levels will be increased due to the melting ice in Greenland. Moreover the risk of burning will increase due the drying tropical rain forests which will add into the amount of carbon dioxide. In next 100 years, temperature will increase by about 10 degrees. Such warming has never occurred in the history of humans. It will destroy vegetation. Erosion of soil will be increased and food will be no more produced. The affects will be numerous.
The climatologists do not say that this will happen. The only warn us about the up coming troubles which should be dealt in time. Global Dimming and Global Warming are now adjacent and we should plan to tackle both issues simultaneously. If we do not plan to control pollution now than it will be too late for us as the days in 2040s will be drastic. Not only must the increasing amount of pollutants be controlled but also the existing quantity of green house gases. Only then we will be able to continue living on this planet comfortable.