The Growing Threat of Global Warming

Global warming refers to the increase in temperature of the earth's surface, including land, water and near-surface air. It is mostly caused due to human-produced increases in atmospheric greenhouse gases. Human activities since the start of the industrial era around 1750 have increased the levels of greenhouse gases in the atmosphere. The largest producers of these gases are the thermal power plants, which burn the fossil fuels and produce these gases in large quantities. The second biggest sources of these greenhouse gases are the road vehicles and industries. Greenhouse gases are gases in an atmosphere that absorb and emit radiation within the thermal infrared range. These gases trap the sun’s infra-red rays in the earth’s atmosphere, which in turn heat up the earth’s atmosphere. The effects of the greenhouse are visible more prominently in recent years, with the number of natural calamities on the rise in the whole world. Greenhouse Gases includes:

• Water vapour
• Carbon dioxide
• Methane
• Nitrous oxide
• Ozone
• Chlorofluorocarbons
• Sulphur hexafluoride
• Hydrofluorocarbons
• Perfluorocarbons

Global warming is also known as 'Green House Effect'. The name comes from an incorrect comparison with the warming of air inside a greenhouse compared to the air outside the greenhouse. The theory that gases in the atmosphere might increase planet earth’s temperature was first postulated by Joseph Fourier in the 1820's, a scientist who also seems to have coined the term “greenhouse gases.” The theory was firstly and reliably experimented on by John Tyndall in 1858. But it wasn’t until 1896 that a research chemist by the name of Svante Arrhenius quantified the greenhouse gas theory and apparently coined the term “greenhouse effect.” The US Environmental Protection Agency (EPA) ranks the major greenhouse gas contributing end-user sectors in the following order: industrial, transportation, residential, commercial and agricultural. Major sources of an individual's greenhouse gas include home heating and cooling, electricity consumption, and transportation.

How Serious is the Threat of Global Warming?
There are certain sections of the society which believe that global warming is a natural process and cannot disturb our ecosystem. According to them - 'The earth’s surface mean temperature was even higher a long time ago and the ecosystem has evolved from that temperature to this. So it can evolve further. But the changes that are happening now are rather fast compared to earlier times. Research reveals - The average facade temperature of the globe has augmented more than 1 degree Fahrenheit since 1900 and the speed of warming has been almost three folds the century-long average since 1970.  Increasing concentrations of greenhouse gases in the atmosphere are causing an unprecedented rise in global temperatures, with potentially harmful consequences for the environment and human health. Earth's temperature rose by 0.74 °C ± 0.18 °C over the period 1906–2005. The rate of warming over the last half of that period was almost double that for the period as a whole (0.13 °C ± 0.03 °C per decade, versus 0.07 °C ± 0.02 °C per decade). The sharp acceleration in CO2 emissions since 2000 to more than a 3% increase per year (more than 2 ppm per year) from 1.1% per year during the 1990s is attributable to the lapse of formerly declining trends in carbon intensity of both developing and developed nations. Although over 3/4 of cumulative anthropogenic CO2 is still attributable to the developed world, China was responsible for most of the global growth in emissions during this period. Average (Earth) temperatures have climbed 1.4 degrees Fahrenheit (0.8 degree Celsius) around the world since 1880, much of this in recent decades, according to NASA's Goddard Institute for Space Studies.

Causes of Global Warming

There are various causes of Global warming. Some of those are explained below:

• Power Plants: Power plants are the major source of carbon dioxide. These power plants emit large amounts of carbon dioxide produced by the burning of fossil fuels for the purpose of electricity generation. Coal is the major fuel that is burnt in these power plants. Coal produces around 1.7 times as much carbon dioxide per unit of energy when flamed as does natural gas and 1.25 times as much as oil. The coal gives out eighty per cent more carbon per unit of energy it produces as compared to natural gas.
• Vehicles: Another major source of carbon dioxide in the atmosphere is the emission from the cars and other vehicles. About twenty per cent of carbon dioxide emitted in the atmosphere comes from burning of gasoline in the engines of the vehicles. This is true for most of the developed countries.
• Deforestation: Another major cause of global warming is deforestation. Deforestation is to be blamed; for 25% of all carbon dioxide release entering the atmosphere, by the cutting and burning of about 34 million acres of trees each year. Trees collect the CO2 that we breathe out and give away from various other sources, and they give back oxygen that we breathe in. Thus, cutting of trees is leading to greater concentration of carbon dioxide in the atmosphere. Greater urbanization, the requirement of land for factories and buildings, the requirement of timber are all reasons that are leading to deforestation, which in turn is leading to global warming. Land use change (main deforestation in the tropics) account for up to one-third of total anthropogenic CO2 emissions.
• Construction: Buildings, both commercial and residential represent a larger source of global warming pollution than cars and trucks. The building of these structures requires a lot of fuel to be burnt which emits a large amount of carbon dioxide in the atmosphere. 
• Agricultural Activities: Almost in all parts of the world, rice is grown on flooded fields. When fields are flooded, anaerobic situation builds up and the organic matter in the soil decays, releasing methane into the atmosphere. Use of fertilizers also leads to higher nitrous oxide (N2O) concentrations. Livestock enteric fermentation, manure management, land use, wetland changes, pipeline losses and covered vented landfill emissions also lead to higher methane atmospheric concentrations. Many of the newer styles fully vented septic systems that enhance and target the fermentation process also are sources of atmospheric methane. 
• Refrigeration and Manufacturing: Use of chlorofluorocarbons (CFCs) in refrigeration systems and use of CFCs and halons in fire suppression systems and manufacturing processes is another major cause of harmful gases being released into the atmosphere.

Effects of Global Warming

• The global warming has led to an increase in mean earth surface temperature and thus melting of polar ice. There is a frequent meltdown of glaciers that result in floods and other natural calamities. The melting of ice at the poles had led the mean sea level. And a further increase in temperature may further melt the ice and lead to a further increase in mean sea level, which will engulf low lying countries.
• The effect of global warming is very evident in the animal kingdom also. Some animals have become extinct due to loss of their natural habitat or their inability to evolve to the rapid changes in the climate. Also, there is a change in their lifestyle because of the changes in the seasons. The migrating birds have changed their time of travel and also their place of migration. It is considered that many species will die off or become extinct due to the increase in the temperatures of the water, whereas various other species, which prefer warmer waters, will increase tremendously. Perhaps the most disturbing changes are expected in the coral reefs that are expected to die off as an effect of global warming. Even the penguins that live on poles are getting affected as a result of global warming. Due to the melting of polar ice their life cycle is getting disturbed and which leads to the death of many animals.
• The effect of global warming can be felt in seasons too. There is a shift in the seasonal cycle, as the summers are getting longer than the winters. This has affected the animals and made them change their lifestyle accordingly, and those who failed to do so have perished or on the verge of extinction.
• Global warming is also responsible for the introduction of some new diseases. The bacteria are more effective and multiply much faster in warmer temperatures compared to cold temperatures. The increase in temperature has led to an increase in the microbes that cause diseases.
• Global warming is also affecting the crop production, as the crops are getting destroyed by the sudden change in temperatures or sudden onset of rains. Also, the flash floods and other natural calamities affect the crop.
• As a matter of fact, because of global warming, the earth’s atmosphere is getting more unpredictable with heavy rains in the areas, which have scanty rainfall or drought in the areas, which received good annual rainfall. The months of rainfall has also getting affected.

How to Control Global Warming?

• Alternative Transportation: Hybrid cars play a significant role in reducing carbon emission as they emit very less harmful gases. They not only greatly reduce carbon dioxide emissions but they also save money. Carbon emissions from single person car transport are the number one most preventable carbon emitter. Using public transportation system, cycling and walking short distances can greatly reduce global warming.
• Energy Efficient Appliances: Using energy efficient equipment has an indirect effect on electricity consumption. Less usage of energy means less production. Appliances like washing machines, dryers, heating appliances etc. use the most electricity. Today, most of the appliances come with energy efficient ratings.
• Save and Conserve: This is also an indirect step based on less consumption resulting in less production. Conservation of energy through small steps like using A.C / Heaters judiciously or keeping the temperature at a conservative level, changing light bulbs to compact fluorescent, turning off electrical equipment instead of 'Stand By' mode can help to save both electricity bill and the environment. 
• Reduce, Reuse and Recycle: Waste needs to be converted into reusable products instead of disposing of. Buying products with minimal packaging (including the economy size when that makes sense for you) will help to reduce waste. Recycling of paper, plastic, newspaper, glass and aluminium cans is the need of the hour. 
• Use of Alternative Technology: Alternative technologies include:
  • Solar Energy: It is usually generated by solar panels or a solar tower.
  • Wind Energy: It is usually generated by groups of wind turbines.
  • Biomass Energy: It is derived from lumber mill wastes, urban wood waste, forest and agricultural residues and other feedstocks as well as waste from factories and landfills.
  • Geothermal Energy: It is derived from steam and hot water found deep beneath the Earth's surface.
  • Hydrogen Energy: It has tremendous potential as a fuel and energy source but the technology needed to realize that potential is still in the early stages.
  • Ocean Energy: It is derived from ocean waves and tides to generate electricity. Ocean thermal energy from the heat stored in seawater can also be converted to electricity.

• Afforestation: Trees and other plants absorb carbon dioxide and give off oxygen during photosynthesis. Plants and trees can fully counter the increases in carbon dioxide caused by automobile traffic, manufacturing and other human activities. A single tree can absorb approximately one ton of carbon dioxide during its lifetime.
• Mutual Cooperation: All countries can make certain policies and programmes aimed at preventing and reducing global warming. One such example is 'The Kyoto agreement' that has been made between various nations to reduce the emissions of various greenhouse gases. 
• Awareness: Taking part in global and community events such as Earth Day is an excellent way to promote awareness among the masses about this crucial issue. Al Gore was one of the foremost U.S. politicians to have an alarm about the hazards of global warming. He has produced a significantly acclaimed documentary movie called "An Inconvenient Truth," and written a book that archives his advice that Earth is dashing toward an immensely warmer future.