Composition & Essay Writing ( 26 )

26- ] Composition & Essay Writing .

19-] Global Warming .

                              The increase of greenhouse gas concentration [ mainly carbon dioxide ] led to a substantial warming of the earth and the sea called global warming . In other words the increase the man-made emission of greenhouse gases is the cause of global warming .

                               Greenhouse gases in the atmosphere act like a mirror and reflect back to the earth a part of the heat radiation which would otherwise be lost to space . The higher the concentration of greenhouse gases like carbon dioxide in the atmosphere , the more heat energy is being reflected back to the earth . The emission of carbon dioxide into the environment mainly from burning of fossil fuels ( oil , gas , petrol , kerosene , coal etc. ) has been increased dramatically over the past 50c years .

                             Almost 100% of the observed temperature increase over the last 50 years has been due to the increase in the temperature of greenhouse gas concentrations like water vapor , carbon dioxide , methane and ozone . The largest contribution source of the greenhouse gas is the burning of fossil fuels leading to the emission of carbon dioxide . Other greenhouse gases include but not limited to nitrous oxide , sulfer hexafluoride and chlorofluorocarbons .

                     There are two major effects of global warming 1-] Increase of temperature on the earth by about 3 to 5 degrees centigrade by the year 2100 . 2-] Rise of sea level by at least 25 meters by the year 2100 .

                     Increasing global temperatures is causing a broad range of changes . Sea levels are rising due to thermal expansion of the ocean , in addition to melting of land ice . The total annual power of hurricanes has already increased markedly since 1975 . Changes in temperature and precipitation patterns increase the frequency , duration and intensity of other extreme weather events such as floods , droughts heat waves and tornadoes . Other effects of global warming include higher or lower agricultural yields , further glacial retreat , reduced summer stream flows and species extinctions .

                     400.000 square miles of Arctic sea ice have melted in the last 30 years threatening polar bear habitats and further accelerating global warming worldwide according to the Arctic Climate Impact Assessment . About 15-37% of plant and animal species global warming could wipe out by 2050 .

                    Everyone is responsible for the global warming as the emission of carbon dioxide is the main cause . It is emitted from our use of fossil fuels. We can lessen our consumption of petrol in our cars , natural gas and energy . Take your personal responsibility seriously regarding the pollution which your existence and behavior either directly or indirectly creates . You do not only help prevent the earth from collapsing , but you help yourself too .

 

20-] Clean Energy / Renewable Energy .

                        Renewable energy sources are considered sustainable in the sense that they can not run out and their environmental and social impacts are generally more benign than those of fossil fuels . Renewable energy is generated from natural resources such as sunlight , wind ,rain , tides and geothermal heat which are renewable [ naturally replenished ] .

                        The majority of renewable energy technologies are powered by the sun . Renewable energy flows involve natural phenomena such as sunlight , wind tide and geothermal heat . Renewable energy is derived from natural processes that are replenished constantly . In its various forms it derives directly from the sun or from heat generated deep within earth . Included in the definition is electricity and heat generated from solar , wind , ocean , hydropower , biomass , geothermal resources and biofuels and hydrogen derived from renewable resources .

                        The wind power for example , can be used through air flows to run wind turbines in wind farms . There are many forms of water energy – hydroelectric [ dams and waterfalls , rivers etc. ] , dams hydro systems

[ derive kinetic energy from rivers and oceans ] , ocean energy [ using the kinetic energy of marine currents , tidal power [ energy from the tides ] , vortex power [ placing obstacles in water to cause the formation of vortices to be tapped for energy ] .

                        Agriculturally produced biomass fuels such as biodiesel , ethanol and bagasse [ by-product of sugar cane - the dry pulpy residue left after the extraction of juice from sugar cane. ] can be burned in internal combustion engines or boilers . Biogas can be easily produced from current waste such as of paper and sugar production , sewage , animal waste and so forth .

                        While most renewable energy [ projects and production ] in large-scale renewable technologies are also suited to small off-grid applications , sometimes in rural and remote areas where energy is often crucial in human development . Kenia has the world’s highest household solar ownership rate with roughly 30.000 small [ 20-100 watt ] solar power systems sold per year . More Kenyans adopt solar power every year than make connections to the country’s electric grid . So , renewable energy can be particularly suitable for developing countries to alleviate poverty to provide cheap energy for businesses and home use . Moreover , scientists from the University of Kassel have suggested that Germany can power itself entirely by renewable energy .

                        In 2006 about 18% of global final energy consumption came from renewables with 13% coming from traditional biomass such as wood burning . Hydroelectricity was the next largest renewable source providing 3 % of global energy consumption and 15 % of global electricity generation.

Wind power is growing at the rate of 30 % annually . Solar thermal power stations operate in the USA and Spain . Brazil has one of the largest renewable energy programs in the world involving production of ethanol fuel from sugar cane and ethanol now provides 18 % of the country’s automotive fuel . Ethanol fuel is widely available in the USA . By the end of 2008 there were 35.000 filling stations throughout Brazil with at least one ethanol pump . Most cars on the road today in the US  can run on blends of up to 10 % ethanol and the motor vehicle manufacturers already produce vehicles to run on much higher ethanol blends .

                        Although some renewable energy technologies are criticized for being intermittent or unsightly , the renewable energy market continues to grow . Climate change concerns coupled with high oil prices , peak oil and increasing government support – all in favor of the increasing use of the renewable energy – clean energy – energy of the future .