What is climate change?
During the last century, concern has grown about the pace at which climate change has been progressing and the extent to which human activity may be aggravating and distorting natural processes.
Climate change is widely believed to be caused by increased levels of polluting gases in the atmosphere, leading to a 'greenhouse effect'. The main source of pollution is carbon dioxide emissions from the burning of fossil fuels, attributable to traffic and industry.
In simplest terms, the 'greenhouse effect' occurs because pollutant gases in the atmosphere trap the sun's energy on earth. This blanket of gases acts in the same way as the glass roof of a greenhouse, allowing the sun's energy to pass through it to reach the earth, but preventing some of the energy from escaping.
The impact of this process is a general increase in average global temperatures.
In the short term, climate change can and has led to increased flooding, drought, famine and eradication of plant and animal species, among other effects. In the long-term, scientists have warned that global warming could potentially have catastrophic consequences for the planet.
The issue of climate change was first considered on the international stage at the UN conference on Sustainable Development held in Stockholm in 1972.
It has subsequently formed the main focus of world summits on sustainable development in Rio in 1992, and in Johannesburg in 2002, underscoring the common perception that climate change is the most serious environmental challenge facing modern society.
The United Nations Framework Convention for Climate Change was established in 1992 and entered into force on 21 March 1994. The Kyoto Protocol of 1997 is the mechanism for implementing the aims of the Convention. The Protocol was adopted in Kyoto, Japan, on 11 December 1997 and entered into force on 16 February 2005.
The detailed rules for its implementation were adopted in Marrakesh in 2001, and are called the “Marrakesh Accords.” Kyoto committed 'industrialised nations' to reduce their greenhouse gas (GHG) emissions by an average of five per cent against their 1990 levels over the five-year period 2008-2012.
Although Kyoto has attracted worldwide support, it has been somewhat undermined by the refusal of the United States – one of the world's most prolific polluters – to ratify the protocol. The US claims it is committed to reducing carbon emissions in line with the principle established by the UN Convention but argues that the framework established by the Kyoto Protocol is unsuitable.
The UK pledged to fulfil the Kyoto protocol and the government laid down a number of domestic strategies to meet its obligation to reduce greenhouse gases.
The principal elements of the UK government's strategy were outlined in the 1998 report, 'A better quality of life, a strategy for sustainable development for the UK', and in the 2003 energy white paper, 'Our energy future- Creating a low carbon economy'. The white paper included a commitment "to put ourselves on a path to cut the UK's carbon dioxide emissions - the main contributor to global warming - by some 60 per cent by about 2050 with real progress by 2020."
In 2003 a UN monitoring panel reported that the UK was the world's sixth most successful country in reducing man-made climate-changing carbon gas emissions and was on course to meet international targets, having reduced emissions by 12.8 per cent since 1990.
Such commitments, though ambitious, were not enough to satisfy a growing awareness of the dangers posed by climate change. In 2006, the economist Nicholas Stern published the Stern Review of the Economics of Climate Change, which looked at the impact of climate change on the world economy. The review suggested that one per cent of global gross domestic product should be invested per annum to avoid the worst consequences of global warming - and avert a 20 per cent drop in potential global GDP.
April 2007 saw the UN's independent panel on climate change publish its third report which warned of a much greater impact than previously anticipated. The poorest were the most likely to suffer from the effects of climate change, according to the report, with rising sea levels, heightened drought risks and negative agricultural impacts all expected to cause more suffering around the world. A later report warned that global temperatures could rise 4C (7.2F) by the end of the century.
In March 2007 the British government published the climate change bill in response to the Stern Review. This piece of legislation was hailed as the first of its kind. It committed the UK to a future as a low-carbon economy. Central to the bill was a legally binding target of at least an 80% cut in greenhouse emissions by 2050, to be achieved through action in the UK and abroad. The bill became law in November 2008.
At the Bali conference in December 2007, delegates sought to set an agenda for negotiations on how to replace Kyoto and, after initial deadlock, agreed on a 2009 deadline for concluding an agreement on measures to reduce pollution. The US had been booed for refusing to commit to EU-led binding targets on reduction targets, but eventually bowed to international pressure.
Agreements reached at the 2010 UN climate change conference in Cancun, Mexico, were said to form the basis for "the largest collective effort the world has ever seen" to reduce emissions.
They included what was described as "the most comprehensive package ever agreed by Governments to help developing nations deal with climate change"; and "a timely schedule" for nations under the Climate Change Convention to review the progress they make towards their expressed objective of keeping the average global temperature rise below two degrees Celsius.
The following year, countries meeting at the climate change conference in Durban, South Africa, announced that they had "delivered a breakthrough" on the future of the international community's response to climate change.
Governments agreed to adopt a universal legal agreement on climate change "as soon as possible, but not later than 2015". Governments, including 35 industrialised countries, also agreed a second commitment period of the Kyoto Protocol from January 1, 2013.
Christiana Figueres, executive secretary of the UN Framework Convention on Climate Change (UNFCCC), said: "This is highly significant because the Kyoto Protocol's accounting rules, mechanisms and markets all remain in action as effective tools to leverage global climate action and as models to inform future agreements."
There are a number of obstacles against dealing with climate change: firstly, scientific opinion varies widely on precisely what climate change will or may do; secondly, it is not an issue that any one country or government can address alone, generating a problem of 'free riders'; and thirdly, it demands dramatic changes to patterns of human behaviour and economic activity today for no immediate benefit.
This latter factor presents particular problems for developing countries. They have seen the West achieve its wealth through industrialisation without massive regard for the environmental consequences, but are now being asked by the West to avoid the same methods for economic development.
The effectiveness or otherwise of the Kyoto Protocol is an on-going source of controversy. In December 2011, a day after new agreements had been reached at the Durban conference, Canada announced that it was withdrawing from the Protocol.
The move was not unexpected as the Canadian government had announced back in 2007 that it would not try to meet its emissions target. Canadian environment minister Peter Kent said that Canada would continue working to reduce emissions, but he believed the Kyoto Protocol was not the right way forward as two of the world's largest polluters, the United States and China, had refused to sign up to the agreement.
Air pollution from the 10,000 largest polluting facilities in Europe cost citizens between € 102 and 169 billion in 2009.
Half of the total damage cost (between € 51 and 85 billion) was caused by just 191 facilities.
Emissions from power plants contributed the largest share of the damage costs (estimated at €66–112 billion).
Other significant contributions to the overall damage costs came from production processes (€23–28 billion) and manufacturing combustion (€8–21 billion).
Sectors excluded from the EEA analysis include transport, households and most agicultural activities – if these were included the cost of pollution would be even higher.
Source: European Environment Agency report, 'Revealing the costs of air pollution from industrial facilities in Europe' - December 2011
"We have taken crucial steps forward for the common good and the global citizenry today. I believe that what we have achieved in Durban will play a central role in saving tomorrow, today."
Maite Nkoana-Mashabane, South African minister of international relations and co-operation and President of the Durban UN Climate Change Conference – December 2011
"I salute the countries who made this agreement. They have all laid aside some cherished objectives of their own to meet a common purpose - a long-term solution to climate change."
Christiana Figueres, executive secretary of the United Nations Framework Convention on Climate Change (UNFCCC), speaking at the Durban conference – December 2011
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