What is Global Warming?
Global warming is when the earth heats up (the temperature rises). It happens when greenhouse gases (carbon dioxide, water vapour, nitrous oxide and methane) trap heat and light from the sun in the earth’s atmosphere, which increases the temperature. This hurts many people, animals and plants. Many cannot take the change, so they die.
Many things cause global warming. One thing that causes global warming is electrical pollution. Electricity causes pollution in many ways, some worse than others. In most cases, fossil fuels are burned to create electricity. Fossil fuels are made of dead plants and animals. Some examples of fossil fuels are oil and petroleum. Many pollutants (chemicals that pollute the air, water and land) are sent into the air when fossil fuels are burned. Some of these chemicals are called greenhouse gasses.
Cars, buses and trucks are also responsible for over 50 per cent of dangerous chemicals let into the air. Some of these chemicals can cause cancer, birth defects, troubled breathing, brain and nerve damage, lung injuries and burning eyes. Some of the pollutants are so harmful that they can even cause death.
Global warming is the greatest challenge facing our planet. It is, in fact, the increase in the temperature of the earth’s neon-surface air. It is one of the most current and widely discussed factors. It has far-reaching impact on biodiversity and climatic conditions of the planet. Several current trends clearly demonstrate that global warming is directly impacting on rising sea levels, the melting of ice caps and significant worldwide climate changes. In short, global warming represents a fundamental threat to all living things on earth.
Effects of Global Warming
Unfortunately, the imbalance which we have created between our life and earth is already showing the signs of disasters in the form of floods, cyclones, landslides, tsunami, droughts, etc. If the imbalance continues to rise, one day this will pose a question mark on the existence of this planet. Carbon dioxide (CO2) which is an important constituent of environment is causing a warming effect on the earth’s surface.
It increases the evaporation of water into the atmosphere. Since water vapour itself is a greenhouse gas, this causes still more warming. The warming causes more water vapour to be evaporated. The CO2 level is expected to rise in future due to ongoing burning of fossil fuels and land use change. The rate of rise will depend largely on uncertain economic, sociological, technological and natural developments. Other gases such as methane, CFCs, nitrous oxide, tropospheric ozone are also responsible for global warming. Increases in all these gases are due to explosive population growth, increased industrial expansion, technological advancement, deforestation, growing urbanization, etc.
Trees play a significant role in the global carbon cycle. They are the largest land-based mechanism for removing carbon dioxide from the air. Deforestation is checking these positive processes. It is the second principal cause of atmospheric carbon dioxide. Deforestation is responsible for 25 per cent of all carbon emissions entering the atmosphere, by the burning and cutting of 34 million acres of trees each year. Every day over 5,500 acres of rain forest are destroyed. As a consequence of massive loss of forests, global CO levels rise approximately 0.4 per cent each year, the levels not experienced on this planet for millions of years. As we know the forests are the great absorbers of C02. The sea levels, as a result of melting of glaciers, have risen from 0.35 mm to 0.4 mm. Scientists have warned in their reports that most of the glaciers will disappear within a period of 15 to 25 years. It will create problems of drinking water and food grains in most of the North American countries. India is not unaffected from it. The Himalayan glaciers have shrunk about 30 per cent after 1970.
The rise in sea levels is a major cause of concern. A large number of cities located in coastal areas will submerge in the sea. Besides, many island countries will ultimately lose their existence and will be washed away from the surface of the earth. The damage of rising sea levels is diverse. Buildings and roads close to the water could be flooded and they could suffer damage from hurricanes and tropical storms. Experts believe that global warming could increase the intensity of hurricanes by over 50 per cent. In addition, as the sea rises, beach erosion takes place, particularly on steep banks.
Wetlands are lost as the level rises. Rise in atmospheric temperature will lead to the outbreak of air-borne and water-borne diseases. It would also contribute to the rise in death caused by heat. The problem of drought would be frequent. Consequently, malnutrition and starvation will pose serious challenge before humanity.
Global warming is a great threat to the flora and fauna of the earth. A large number of species of them may become extinct.
The expanse of desert would increase. Low rainfall and rising temperature could add to the intensity and frequency of dusty storm. This in turn will immensely affect the quality of agricultural land, ultimately causing adverse effect on agricultural produce. It would have far-reaching socio-economic impact.
In Indian context, the impact of global warming is a matter of grave concern. As is we known, India is mainly an agricultural country and agriculture here is gamble of the monsoon, e.g. largely depending on rainfall. Though it is to affect the whole country, the worst likely impact would be on central and northern India which is high-yielding part of the country. These are the regions which produce the largest agricultural yield. The rise in atmospheric temperature and fall in rain would naturally result in decline in crop production. Moreover, it would have great effect on biodiversity as well.
The greenhouse effect is when the temperature rises because the sun’s heat and light is trapped in the earth’s atmosphere. This is like when heat is trapped in a car. On a very hot day, the car gets hotter when it is out in the parking lot. This is because the heat and light from the sun can get into the car, by going through the windows, but it cannot get back out. This is what the greenhouse effect does to the earth. The heat and light can get through the atmosphere, but it cannot get out. As a result, the temperature rises.
Sometimes, the temperature can change in a way that helps us. The greenhouse effect makes the earth appropriate for people to live on. Without it, the earth would be freezing or, on the other hand, it would be burning hot. It would be freezing at night because the sun would be down. We would not get the sun’s heat and light to make the night somewhat warm. During the day, especially during the summer, it would be burning because the sun would be up with no atmosphere to filter it; so people, plants and animals would be exposed to all the light and heat.
Although the greenhouse effect makes the earth able to have people living on it, if there gets to be too many gases, the earth can get unusually warmer, and many plants, animals and people will die. They would die because there would be less food (plants like corn, wheat and other vegetables and fruits). This would happen because the plants would not be able to take the heat. This would cause us to have less food to eat, but it would also limit the food that animals have. With less food, like grass, for the animals that we need to survive (like cows), we would even have less food. Gradually, people, plants and animals would all die of hunger.