Methane contributes a lot in the scheme of things and is mainly caused by the break down of organic matter. And you could say this is natural but it has increased due to concentrated farming like paddy fields in Asia. Other sources consist of cows, swamps and marshes. Methane also absorbs long wave radiation like Carbon Dioxide.
CFC’s are a huge input to the greenhouse gases. They come from things like fridges and aerosols and extremely polluting. They make up at the moment roughly 25% of the gases but are increasing at a rapid rate as they are able to stay within the atmosphere for as much as 100 years.
Nitrous oxide is another contributor to the greenhouse gases. It too absorbs long wave radiation just like the other pollutants. This nitrous oxide comes from many things like nitrate fertilisers which are widely used in farming. A lot comes from transport and the use of cars etc. And some comes from power stations and the process of combustion.
The affect of these pollutants spread over a wide variety of different things. IT has a huge impact on health due to the rise in temperature. Disease such as cholera and malaria thrive in the rising temperatures and are dangers to a huge population. This has an affect on other things as well. By increasing the disease it puts a strain on the medical services and more money is needed to fight them.
There is an effect on vegetation due to this change. As the temperature increases, the flora and fauna (both areas of different vegetation growth), move to different areas and can have a huge affect on local crops. This rise in temperatures can also mean the extinction of some species. With this change in vegetation comes the threat of wide spread disease and pests problems. It can also force a change in crop yields and may force and increase in food shortages. A positive affect of this however is that what once were poor areas for farming may now become new major crop belts. For example the wide vast prairies of Canada may become a vital wheat growing area.
With the increase in temperature comes the threat of devastating new weather. Damaging hurricanes will increase in numbers and frequency.
As the sea temperatures rise and levels change the number of fish stocks and location will differ and this will have a huge impact on the fishing industry. There will however be an increase in fish stocks in some areas and so, will improve the areas economy and society.
There is a instant need to combat that this change in temperature and the only way to do this is by stopping the increase in greenhouse gases. Some ways of fighting this have been put forward.
Switch from use of fossil fuels to ‘greener’ sources of energy, for example, renewable energy such as wind power, hydro-electric power and nuclear power. Changing to nuclear power is one of the fastest ways of reducing carbon dioxide (CO2) output. Increase tariffs on industry for emitting greenhouses gases however it would be difficult to enforce effectively. In the UK government legislation already exists, and new buildings now have a minimum of 20% increase in their energy efficiency. Fines often mean little to large industries. Price fuels so that their cost reflects the impacts that they have on the environment. Limit the amount and rate of deforestation by provision of relevant management strategies. And replant trees as it would reduce soil erosion, and absorb carbon dioxide. Invest more money into public transport and increasing fuel efficiency of cars, for example.
The ozone layer is found in the upper stratosphere and its primary function is to filter ultraviolet short-wave radiation that comes from the sun. Ozone gas absorbs UV radiation. The ‘hole’ in the ozone layer was first noted in the 1980’s, and is of concern as increased levels of UV radiation can leads to increased levels of skin cancer and eye cataracts.
At first the ozone hole was only found over Antarctica, but it has been becoming larger at a rapid rate, and now affects parts of Chile and Australia. Although some natural repair occurs each year, it is not sufficient to limit the damage. The problem is worsened as CFC’s are a primary cause of the damage and they remain in the stratosphere for up to 100 years.
There are two main sources source’s of the gases damaging the ozone. The increase in the size of the hole in the ozone layer is directly linked to increased production of CFC’s since the 1950’s in aerosols, plastic foam, fast food packaging and fridges. Chlorine is produced by CFC’S and reacts strongly with ozone in the stratosphere, breaking down the ozone layer.
Natural gases contribute to this as well. They come from volcanic eruptions, as they release carbon monoxide and decrease nitrogen oxides in the atmosphere. Methane comes from rotting vegetation.
The consequences of this depletion within health are large. The main concern is the increase in levels of UV radiation and the link to skin cancer. It is also connected to eye damage, where the cornea, retina and lens may be damaged. In severe cases, cataracts form.
Vegetaion is affected as it inhibits photosynthesis in plants and increases the likelihood of disease. Some evidence is contradictory.
The solutions to ozone depletion are mainly on decreasing the amount of emissions. This can be put forward by education; it was pioneered in Australia, with the Sunsmart Campaign, advising people to cover up when out in the sunshine to reduce the damage caused by UV radiation. Government legislation is another way of doing it and again Australia lead the way in 1989 ‘Ozone Protection Act’ banning production of import and manufacture of all CFC’S. Also with the restriction of aerosol use.
Many countries have realized the threat and have begun to sign up to world wide agreements such as the Kyoto agreement in which the countries vowed to cut down emissions to a certain level.
