Give a brief explanation of how increasing levels of combustion of fossil fuels is causing global warming and climate change and what measures are being taken to address this problem.

In recent decades there has been much debate about the rise in global temperatures and the level of polluting emissions different nations are spilling in to the atmosphere. The increase in these levels of pollutants, a product of burning fossil fuels, is thought by many to be contributing to the warming of the planet. Which if not addressed may cause severe problems for the human race through damaging alterations in climates around the world.

Many fuels burned today are formed from crude oil (and are also alkanes). The discovery that the burning of these hydrocarbons produces atmospheric pollutants had led to a push to become less reliant on these fuels and to move towards using and developing fuels which are less damaging and less polluting.

One of the main waste products of fossil fuels when burned is carbon dioxide, a so called ‘greenhouse gas’, which is viewed by many as the main culprit for the gradual rise in global temperatures seen in the last century. This rise alluded to a moment ago is termed ‘global warming’ where the average global temperatures for the past century have risen measurably.

There still isn’t a complete consensus to the theory of ‘man-made’ global warming, there is a school of thought that suggests that these rises are demonstrative of ‘natural’ changes and the effect of man in burning fuels isn’t having as major an impact upon the environment as is being reported. The debate continues, though it seems that a majority of leading scientists accept that man is more than partly to blame for the recent rises seen in the average global temperature.

The earth’s average temperature has in its history though been much higher than it is presently, as well as significantly lower than is now. The eruption of volcanoes is one natural cause of increased levels of carbon dioxide in the atmosphere, which can cause global warming.

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All (alkanes) hydrocarbon based fuels derived from crude oil may produce polluting products when burned. Carbon dioxide as mentioned is one, as is carbon monoxide, which is a poisonous gas formed as a result of incomplete combustion. Water vapour is another greenhouse gas as well, methane too. The burning of fossil fuels derived from crude oil to generate energy releases these greenhouse gases, which act by preventing heat escaping the atmosphere, and leads to an increased temperature of the planet.

The example of a greenhouse was used because greenhouses are designed to become very warm inside, trapping warm air. This is because visible rays from the sun pass through the glass, instead of escaping, their energy is absorbed by everything inside the greenhouse and ‘re-radiated as infra-red energy’- which is heat. As the infra-red energy has a shorter wavelength it cannot pass back out through the glass, it therefore stays in the greenhouse. This scenario can be used to explain what happens in the atmosphere where carbon dioxide in this instance behaves much like the glass in a greenhouse. It acts like a blanket, and traps the infra-red radiation, in so doing the earth’s atmosphere heats up. Carbon dioxide is necessary in the atmosphere, as for without it the earth would become too cold to sustain life. But increasing levels of it in the atmosphere means more heat is becoming trapped in the atmosphere and consequently it further heats it up.

The main greenhouse gases are carbon dioxide, water vapour and methane. Though levels of water vapour and methane has been measured and shown not to have altered significantly in recent years, whereas carbon dioxide levels have, and significantly so. Though water vapour and methane are more ‘effective’ in the process than carbon dioxide it is felt by scientists that the rising levels of carbon dioxide, through the increase in the combustion of fossil fuels over the last century, has a direct correlation/link with the increase in the average global temperature over the same period.

Increases in global temperatures through global warming as a result of increased carbon dioxide trapped in the upper atmosphere is likely to cause climate change, where weather patterns are shifted and unusual weather occurs in differing regions of the planet. Climate change may be beneficial to some regions, though in other regions it may be devastating. Growing season will be affected and use of land altered, that’s if land remains above sea levels, as it is forecast sea levels will rise as a result of global warming as ice caps at the polar regions will melt. Warming of the planet has brought unpredictable changes in weather patterns around the globe, with storms and hurricanes seemingly to have become more severe and more frequent in recent years.

One such measure taken in reducing the level of greenhouse gases into the atmosphere are the signing of treaties to agree to reductions in the level of pollutants a country produces, the creation of the Kyoto agreement in the 1990’s was a response to the discovery of rising levels of carbon dioxide in the atmosphere, which is causing global warming and climate change as a result.

The agreement set out targets countries are expected to meet by a certain time, however, in 2001 the treaty was dealt a severe blow when the USA withdrew, citing economic and scientific reasoning behind their decision, since they are the single biggest contributor to the creation of greenhouse gases it was seen as a major blow by all.

Another measure that can be introduced is the creation of green taxes, where for example a tax is added to flight prices to partly try and deter people from flying. Many air carriers today offer passengers the option of paying a little extra to offset their carbon dioxide as well, where organisations will plant trees, which absorb carbon dioxide, in a process of ‘offsetting’ a passengers direct carbon dioxide share/contribution, thus enabling the passenger to travel ‘carbon neutrally’.

Governments around the world in trying to meet targets, tend to offer incentives to companies who use alternative means of energy, with grants and assistance given to forward thinking companies.

The most obvious way of reducing human made carbon dioxide from entering the atmosphere is simply to use other forms of energy, which don’t produce the polluting greenhouse gases, the increase in the use of hydroelectricity and solar and wind energy must be the way forward. People should also be energy conscious and reduce their consumption wherever possible, thus reducing the levels of carbon dioxide being produced by man.

The development of hydrogen based energy for transport needs is an area under current research and development, which will one day hopefully see us become less reliant on crude oil and its products.

The promotion of recycling is both beneficial to a society in terms of environmental and economical factors. The re-use of plastics and metals should be encouraged wherever possible, reducing the need to make new ‘fresh’ product.

One such technique governments are incorporating in reducing their emissions is a process called Carbon capture and Storage (CCS). This is a process whereby waste carbon dioxide is transferred and stored in the deep oceans or stored deep underground, or where it is reacted with metal oxides to form stable minerals.

Encouraging plant and tree growth to replace much of the deforested areas of the world is seen as a key area in increasing photosynthesis, whereby more carbon dioxide is absorbed.

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