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On 22 September, United Nations Secretary-General Ban Ki-moon convened a high-level Summit on Climate Change ahead of the United Nations Climate Change Conference in Copenhagen in December. In that gathering, the Secretary General made it clear that Copenhagen must deal with the need for more ambitious emission reduction targets for industrialized countries.
In the Kyoto protocol, emissions reduction targets were agreed, but at an average of five per cent against 1990 levels over the five-year period 2008-2012, the targets were considered minimal. The issue is that this time carbon dioxide in the atmosphere counts for some 380 parts per million (ppm) already or higher by about 100 ppm before the advent of the industrial revolution, and still rising. The projection is that once it reaches 450 ppm it will also cause the average global temperature to rise by up to 2 degrees centigrade. At the rate man is producing carbon dioxide, global temperature is projected to increase by up to 5 degrees centigrade or more by the end of this century. Thus, the need for cutting down carbon dioxide emissions.
The target hopefully is to keep the increase in the global temperature below 2 degrees centigrade from the present level. This requires carbon dioxide in the atmosphere to be kept within 450 ppm. At this point we do not have any idea yet of the likely carbon dioxide emission cut that will be agreed in Copenhagen. The issue is where and how best a reduction in carbon dioxide emissions can be made, at what cost and for how long, including who will do most of the cutting.
On this matter, the UN Secretary General, in his summary of the September 22 high level summit, said that developed country leaders acknowledged that they must lead and that many leaders referred to the need to reduce developed country emissions by 25% to 40% from the 1990 levels by 2020 but that the targets so far proposed by developed countries are inadequate.
By the way, as the UN climate summit in Copenhagen approaches, BBC News environment correspondent Richard Black traces key milestones, scientific discoveries, technical innovations and political action. Let me just give some of the most important dates and events.
In 1712, British ironmonger Thomas Newcomen invented the first widely used steam engine, paving the way for the Industrial Revolution and industrial scale use of coal. In 1886 German engineer Karl Benz unveiled the Motorwagen, often regarded as the first true automobile, leading eventually to the wide use of gasoline. In 1958, Charles David (Dave) Keeling began systematic measurements of atmospheric CO2 at Mauna Loa in Hawaii and in Antarctica. Within four years, the project provides the first unequivocal proof that CO2 concentrations are rising.
In 1972, the first UN environment conference was held in Stockholm. In 1987, the Montreal Protocol was agreed, restricting chemicals that damage the ozone layer. In 1988, the Intergovernmental Panel on Climate Change (IPCC) was formed to collate and assess evidence on climate change. Its First Assessment Report in 1990 concludes that temperatures have risen by 0.3-0.6C over the last century, that humanity's emissions are adding to the atmosphere's natural complement of greenhouse gases, and that the addition would be expected to result in warming.
In 1992, at the Earth Summit in Rio de Janeiro, governments agreed on the United Framework Convention on Climate Change (UNFCCC) with the key objective of stabilizing greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. Developed countries agree to return their emissions to 1990 levels.
In 1995, the IPCC Second Assessment Report concluded that the balance of evidence suggests a discernible human influence" on the Earth's climate. In 1997the Kyoto Protocol was agreed where developed nations pledge to reduce emissions by an average of 5% by the period 2008-2012.
In 2001, President George W. Bush removed the US from the Kyoto process. In the same year, the IPCC Third Assessment Report found "new and stronger evidence" that humanity's emissions of greenhouse gases are the main cause of the warming seen in the second half of the 20th Century. In 2005, the Kyoto Protocol became international law for those countries still inside it. One year later, the Stern Review concluded that climate change could damage global GDP by up to 20% if left unchecked but that curbing it would just cost about 1% of global GDP.
In 2007, the IPCC's Fourth Assessment Report concluded it is more than 90% likely that humanity's emissions of greenhouse gases are responsible for modern-day climate change. In 2008, half a century after beginning observations at Mauna Loa, the Keeling project showed that CO2 concentrations have risen from 315 ppm in 1958 to 380ppm in 2008.
This year, China overtook the US as the world's biggest greenhouse gas emitter but the US remains well ahead on a per-capita basis. Before the end of the year, 192 governments convene for the UN climate summit in Copenhagen.
