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
Global average temperature rose significantly during the past century. The prevailing scientific view is that most of the temperature increases since mid-20th century has been caused by increases in atmospheric greenhouse gas concentrations produced by human activity. Most scientists agree that planet’s temperature has risen 0.5 degree Celsius since 1900 and will continue to increase at an increasing rate. As a result, the world is getting warmer. The year 1990 was the hottest year in the last century.
Together with 1991, the years of 1983, 1987, 1988 and 1989 have been measured to be the warmest six years in the last hundred years. The year 1991 was the second warmest year of the past century. The consequences of the rise in temperature is being felt all over the globe the findings of scientific research done in this field reveal that the temperature of the earth is likely to rise from 1.4°C to 5.8°C within a period of 100 years.
Unfortunately, the imbalance which we have created between our life and earth is already showing the signs disasters in the form of flood, cyclones, landslides, tsunami, drought, etc. If the imbalance continues to rise, one day this will pose a question mark on the existence of this planet. Carbon dioxide (C02) 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 C02 level is expected to rise in future due to ongoing burning of fossil fuels and landuse 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 and growing urbanisation, 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 principle 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...