Only very wealthy people could actually own and operate cars. However today almost everyone owns a car. This is because machines produce other machines and thus reduce the costing of building. Thus it can be said that humans live in a much mechanized world today. The machines however need energy to operate. The biggest source of energy for these machines comes from fossil fuels. This is because humans have still not invented a widely usable perfect substitute for non-renewable energy. The energy used has a very bad impact on the environment. The carbon is residue of most combustion process. This is because humans have still not formed a combustion system which could burn with 100 % efficiency. This level of efficiency means that all the fuel I converted to energy. However the current combustion systems give shockingly less amount of efficiency even lower than 50% in many cases. The carbon fuel that does not converted into energy because of this low efficiency level is emitted into the atmosphere. Combined with other harmful products it becomes major contributor to ozone depletion and global warming. Thus not only is it hazardous to health is inhaled in large quantities but it almost causes irreparable damage to our environment.
In definition global warming refers to the increase temperature near the Earth’s surface. According to scientists this process started in the mid-twentieth century and is still going on. The reports recently released by IPCC (Intergovernmental Panel on Climate Control), in the last few years global temperatures have shown an increase of 0.74 ± 0.18 °C (1.33 ± 0.32 °F). Along with burning of fossil fuels as explained above, the deforestation of rain forests is also a major cause of this increase. According to some shocking reports released by the Intergovernmental Panel on Climate Control the temperatures are expected to rise another 1.1 to 6.4 °C (2.0 to 11.5 °F), in the next few decades.