External Factors which affect climate change
This is energy that comes from the Sun, this changes over time. Mesurements made in the 1980s showed that the total amount of solar energy reaching the earth has decreased by 0.1%. If this trend continued for 100 years it could influence global climate.
It has been predicted that a 1% change in solar output could make the temperature rise of fall by between 0.5 and 1 degrees celsius. The activity of sunspots on the Sun's surface affects solar output. When sunspot activity is reduced, for example between 1645 and 1715 the 'Little Ice Age' took place.
The shape of the Earth's Orbit around the sun varies from nearly circular to elliptical and back to circular again every 95,000 years. Cold, glacial periods have occured when the Earth's orbit is circular and warmer periods when it is more elliptical.
The tilt of the Earth's axis varies over time from 21.5 degrees and 24.5 degrees. This variation occurs over a 41,000 year time span. The greater the angle of the tilt, the hotter the summers are and the colder the winters are.
Internal Factors which affect climate change
Volcanic Eruptions release large amounts of sulphur dioxide and ash into the atmosphere. These act as a cloak and reduce the amount of radiation reaching the Earth's surface. In 1815 Mt Tambora erupted, the following year was unusually cold. 1816 became known as the year without a summer.
During cooler periods when there is a larger amount of snow and ice on the Earth, global temperature will drop due to the snow and ice reflecting sunlight back into space. If the planet warms up, snow and ice will diminish, and the Earth will continue to get warmer.
Change in Atmospheric gas
There is a clear relationship between the amount of CO2 in the atmosphere and temperature variations. CO2 is one of the most important gases responsible for the greenhouse effect. The greenhouse effect keeps heat within the Earth's atmosphere by absorbing longwave radiation. Without the greenhouse effect, the average global temperature would be -18 degrees Celcius rather than the present 15 degrees Celcius.
Internal Factors which affect climate change
The movement of continets caused by plate tectonics affects the global pattern of atmospheric and ocean circulation, and the changing shape of the Earth's surface causes winds and ocean currents to change. The process is too slow to have much effect on climate over the relatively short geological time span of 10,000 years.
Causes of current climate change globally
Burning of Fossil Fuels
Fossil fuels are fuels which are produced from coal, oil and natural gas. These fuels are used to produce energy in power stations and to supply fuel to vehicles. In China 75% of energy is produced from coal. When fossil fuels are burnt gases are released into the atmosphere. One of these gases is CO2 which contributes to the greenhouse effect, causing climate change. The generation of power accounts for 25% of global carbon dioxide emissions.
Increase of Methane in the atmosphere
Methane is a greenhouse gas, this means that it can trap heat within the Earth's atmosphere. it makes up 20% of the greenhouse gases in the atmosphere, and is 20x more potent that CO2.
Methane comes from:
- organisms that were alive many years ago
- recently dead, rotting organisms
- organisms which are alive today
Fossil Methane comes to surface when fossil fuels are mines.
Causes of current climate change locally
Modern methane comes from a variety of sources:
- wetlands including marshes and swamps
- the growing of rice
- landfills which contain rotting vegetable matter
- burning vegetation
- bowels of animals
The levels of methane have been rising
They have risen by 1.5% a year for the past decade, this is due to:
- an increase in the mining of fossil fuels
- rising temperature, which causes an increase in bacteria emissions from wetlands
- an increase in rice production due to the growing population in rice producing countries
- an increase in the number of cattle and sheep for meat
Negative effects of climate change
Changing patterns in crop yields
Countries closer to the equator are likely to suffer the most as their crop yields will decrease. In Africa, countries such as Tanzania and Mozambique will have longer periods of drought, and shorter growing seasons. The could lose 1/3 of their maize crop. It is forecast that in India there will be a 50% decrease in the amount of land available to grow wheat. This is due to hotter and drier weather.
Rising sea levels
Between 1993 and 2006 sea levels rose by 3.3mm a year. This will lead to an 88cm rise in sea levels by the end of the century. This will threaten large areas of low lying costal land such as New York, London and Tokyo. Two of the Kiribati islands are now covered in sea water.
The vast majority of the world's glaciers are retreating, some more quickly than others. This is due to the increase in temperature. 90% of the glaciers in Antartica are retreating. Melting at the poles can affect ocean movement. Melting of ice in the Arctic could cause the Gulf Stream to be diverted south. These leads to cooler temperatures in Western Europe.
Response to Climate Change on a Global level
In June 1992 the United Nations held a meeting in Rio de Janeiro. Named the earth summit because it was made by the world’s most important people. It was the first international environment treaty.
This lead to the Kyoto protocol, signed in December 1997, enforced in February 2005. It was agreed to cut greenhouse gas emissions by 5.2% compared to the global levels of 1990. Each country agreed to reduce theirs by a certain amount:
- UK/EU – 8%
- USA – 7%
- Japan – 6%
- Russia – 0%
By 2008, 181 countries had signed the Kyoto Protocol. In December 2007 a climate change conference took place on the island of Bali. Representatives of more than 180 countries were present. This resulted in the Bali Roadmap in which initiatives were agreed to try and reach a secure climate.
Response to Climate Change on a Global level
Focus on the use of fossil fuels. They are trying to get governments, especially the UK, to change how sustainable their production of energy is.
Greenpeace’s suggested solutions:
- Reduce energy wasted by inefficient power stations. E.g. 2/3 is lost in waste heat in cooling towers. If this heat was captured the amount of fuel needed to produce the energy would be reduced.
- Combine heat and power systems, which produce an energy source for a small area and therefore less energy is wasted.
- Base energy on renewable sources.
- Reduce transport. 22% of the UKs carbon emissions are caused by transport. Low carbon cars can be produced and public transport could be made more efficient. Air traffic produces even more emissions than cars. No new airports and less flights and taxes would help reduce this.
- From 2005, industry has been required to reduce its emissions or buy carbon credits from other companies if they exceed their targets.
Response to Climate Change on a Local level
Live simply is a campaign which ran throughout 2007. It was initiated by the Catholic Church to encourage children to consider life changes. Many Schools are introducing energy efficient water and central heating systems that run from renewable sources. E.g. wind turbines, solar panels. Notices to turn lights off.
Manchester is my planet
Encourages individuals to reduce their carbon footprint and become involved in a number of green energy projects. Started in 2005, and works with the local council. More than 20,000 people have pledged towards their scheme.
People are encouraged by ‘Green parking permits’
- People who have been recognised to have a low carbon emission can apply.
- Allows them to buy an annual parking ticket/permit for NCP car parks within the greater Manchester area, at a 25% discount. Valid for 12 months.
Response to Climate Change on a Local level
UKs target is to cut carbon emissions by 15% below the 1990 levels by 2010, and 20% by 2020.
Councils have an influence on peoples’ homes. 15% of the UKs carbon emissions come from houses. Since April 2008 it has been local councils target to cut down carbon emissions. To do this the government has given them £4,000,000.
The six best councils are:
- Eastleigh Borough
- City of London
- Barking and Dagenham
- Woking Borough
They have introduced schemes which have cut carbon emissions. E.g. giving away energy saving light bulbs. Woking had a CHP scheme (combined heat and power).
Definitions of sustainable development
The Brundtland Report
The United Nations released the report in 1980, it define sustainable development as
"development which meets the needs of the present without compromising the ability of future generations to meet their own needs."
The report focused on three areas:
- the conservation and enhancement of the environment by the development of new technologies.
- the achievement of social equality by developing countires being allowed to meet their basic needs of employment, food, engery, water and sanitation in a sustainable way.
- the economic growth of all counties.
These values were reiterated in 1997 at UNESCO meeting in Paris. They stated that it was the responsibilty of the present generations to bequeath to future generations an Earth which had not been irreversibly damaged by human activity.
Development of the food industry - ASDA
Products which are sold in local Asda stores have travelled many miles. The last part of their journey is from a regional distribution centre. This is a large warehouse where products are stored until the local stores need them. They are then sent to the local stores by lorry.
When the products arrive in the distribution centre they are packed in polythene and shrink wrap. The distribution centre in Didcot, Oxfordshire used to fill a skip four times a week and send it to a landfill site. This was costing Asda a lot of money and was not a sustainable way of dealing with the waste.
The problem was solved by a company called Mil-tek that makes machines to bale plastic. They installed a large machine in the warehouse in Didcot. All the waste plastic is now put into the baler and crushed to 10% of its original size. The bales of plastic are collected once a week by a firm which recycles plastic. This is benefiting Asda which now receives money for the plastic instead of having to pay to have it taken away. It is also benefiting the environment because no plastic is being sent to landfill site.
Development of the communication industry - Nokia
Nokia are concerned that people do not recycle their old phones. This is a very serious situation, as more than 50% of mobile phone users change their phone every year. 44% of these old phones are never used again. Nokia is trying to persuade people to hand in their old phones to recycling points because 100% of the phone can be recycled. Old mobiles can be used to manufacture trumpets, benches or even gold rings. If every mobile phone user recycled one phone it would save 240,000 tonnes of raw materials. Nokia are promoting this campaign in stored which sell their phones and with a very catchy jingle on their website. This website also gives information on where to find recycling points and the address to send the phone to if there is not a centre nearby.
Development of a global company - General Electric
This is a large transnational corporation (TNC) which operates in many different countries. The company has introduced many policies to make it operate in a more sustainable way. One of their pledges is that by 2012 they will reduce fresh water usage by 20%. This is expected to save 7.4million cubic metres of water which is enough to fill 3,000 Olympic sized swimming pools. This will be achieved by assessing their water usage and improving their water recycling. Much of the water in the ir boilers and cooling towers will be recycled water.
Power generation - coal fired power stations
Coal fired power stations provide 38% of the world’s energy and in countries such as India and China they provide more than 75%. This reliance on coal as an energy source and the resultant pollution means that coal-fired power stations need to be as efficient as possible in order to produce the least amount of pollution. Coal-fired power stations emit large amounts of CO2 and SO2 and N2O. The emissions of these gases are a major contributor to both acid rain an climate change. The control of these emission has been dealt with, with varying degrees of success.
Carbon Dioxide - Most power stations are only 36% efficient. If this was raised to 40%, CO2 emissisions drop by 25%. The only way to deal with the emissions is to capture it from the flue gases, by using amine scrubbers. This removes upto 98% of CO2 waste gases.
Sulphur Dioxide - Many power stations have systems which operate in the flue of the boiler to remove SO2 emissions by about 60%. If scrubbers are fitted the figure rises to 95%. In Germany all stations have scrubbers fitted, but this is not the case in LICs.
Nitrous Oxide - Most of the power stations have systems fitted that remove upto 70% of nitrogen emissions.
Management of transport in urban areas
Sustainable transport involves maintaining the standard of transport that is required for society and the economy to function efficiently without placing too much pressure on the environment.In the Sustainable Development Strategy for the UK, the government has stated that it will need to take action to control the rate of traffic growth, improve the performance of vehicles and make the public aware about the environmental impacts of polluting emissions from transport. People need to be encouraged to reduce their dependency on cars, but affordable alternative public transport systems must be available to allow them to do this.
In urban areas of the world there is a great dependency on the car as a means of transport. In both high income countries and low income countries, people are becoming ever more dependent on private vehicles for moving around the city. Car ownership is growing most rapidly in LICs and HICs. In Delhi, India the number of vehicles in the city has grown from 500,000 in 1970 to more than 5,000,000 in 2008.
- Respond to the increasing demand by building more roads – helps congestion, but increases pollution.
- Reduce traffic with a range of sustainable schemes.
Sustainable transport schemes
Making motorists pay to travel into large urban areas during periods of heaviest use - reduces the number of vehicles, which eases congestion and lower pollution emissions. Hopefully lead to people walking and cycling. First city to introduce the scheme was Singapore. They have charged since 1974.
London introduced the scheme in 2003; by 2008 it had had the following beneficial effects:
- Traffic Levels have been reduced by 21%
- 65,000 fewer car journeys a day
- Increase of 29,000 bus passengers during rush hours
- 12% increase in cyclists
- 12% reduction in the emission of nitrous oxide
Durham, introduced their congestion charge in 2002, has seen an 85% drop in traffic entering the zone.
Sustainable transport schemes
Park and Ride
Allow shoppers to park their cars in large designated parking areas on the edge of towns and cities, and catch a bus into the centre. Park and ride operates in87 towns and cities in the UK (including Leicester). Parking is free but there is a charge for the bus journey. They are usually located on the main routes coming in and out of the towns and cities, so are easily accessible for the greatest number of car users. Approximately 40 people will travel on one bus rather than in 40 individual cars, far less congestion and pollution.
Cambridge park and ride
Cambridge has 5 park and ride sites covering all the main routes coming into the city. The Madingly and Trumpington road sites are next the M11 and the Milton and Newmarket road sites are close to the A14 to give easy access for motorists driving into the city. There are 4,500 spaces available. The buses carry up to 70 passengers. It costs £2.20 per day. There are waiting rooms, toilets and baby changing facilities.
Other Sustainable Transport Schemes
- Car sharing where workers share lifts to work using their own cars. If half the UK motorists received a lift one day a week, vehicle congestion and pollution would be reduced by 10%, and traffic jams by 20%.
- Designated cycle and walking paths within the urban area. Milton Keynes is one of the best urban areas in the UK, with 273km of cycle paths.
- Road lanes that only allow cars with at least two passengers to use them.
- Pedestrianised areas which restrict private vehicle access, but allow buses and trams to operate.
- Road lanes which give priority to buses, ensuring they get and easy passage through congested areas.
- Restricting car parking in central urban areas so motorists are forced to use public transport.