The United States emitted more greenhouse gases in 2004 than at any time in history, confirming its status as the world's biggest polluter. Latest figures on the US contribution to global warming show that its carbon emissions have risen sharply despite international concerns over climate change.
The figures, which were quietly released on Easter Monday, reveal that net greenhouse gas emissions during 2004 increased by 1.7 per cent on the previous year, equivalent to a rise of 110 million tons of carbon dioxide.
This is the biggest annual increase since 2000 and means that in 2004 - the latest year that full data is available - the US released the equivalent of nearly 6,300 million tons of carbon dioxide into the atmosphere.
...US emissions have risen by 15.8 per cent from 1990 to 2004, mainly due to increased consumption of electricity generated by burning fossil fuel, a rise in energy demands...and a rise in petrol consumption...
Scientists in Britain condemned the increase, saying that it showed how the US was failing to take a lead in the international attempt to curb greenhouse gas emissions despite being the worst offender.
Professor David Read, the vice-president of the Royal Society, said that the US and Britain needed to take urgent action to reduce greenhouse gas levels in order to honour their commitments to the United Nations Framework Convention on Climate Change.
"The figures published this week show not only that the US emissions are not decreasing, but that they are actually increasing on an annual basis," Professor Read said. "And while the UK appears to be doing slightly better, its carbon dioxide emissions have been rising annually for the past three years," he said. "The US and the UK are the two leading scientific nations in the world and are home to some of the best climate researchers.
"But in terms of fulfilling the commitment made by their signature to the UN convention to stabilise greenhouse gas levels in the atmosphere, neither country is demonstrating leadership by reducing their emissions to the levels required," Professor Read said.
The US accounts for about a quarter of the total global emissions of man-made carbon dioxide or the other gases such as methane that can exacerbate the earth's greenhouse effect, which traps sunlight and heat.
Under the UN climate change convention, America is required to publish its net contribution to greenhouse gas emissions, which takes into account pollution sources, such as cars and industry, and "sinks", such as forests.
The figures show that the total US emissions have risen by 15.8 per cent from 1990 to 2004, mainly due to increased consumption of electricity generated by burning fossil fuel, a rise in energy demands caused by increased industrial production and a rise in petrol consumption due to increased travel. Fossil fuel combustion alone accounted for 94 per cent of the carbon dioxide emissions produced by the US during 2004, the figures show.
Carbon dioxide levels in the atmosphere are now a third higher than they were before the Industrial Revolution began in the 18th century, and probably higher than they have been for at least 10 million years.
Scientists have suggested that if the international community is to try to stabilise carbon dioxide levels at twice pre-industrial levels then countries such as the US and Britain need to reduce emissions by about 60 per cent by the middle of this century.
Professor Read said there was mounting evidence to suggest that rising temperatures caused by greenhouse gas emissions were beginning to cause serious climate effects, such as a drop in annual rainfall in east Africa because of rising water temperatures in the Indian Ocean.
"If emissions continue to rise, we can expect even more impacts across the world," Professor Read said. "The developing world will find it difficult to adapt to climate change and the industrialised countries, which are primarily responsible for the rise in greenhouse gas levels, should realise that they would also struggle to adapt to a world in which, for instance, sea levels are several metres higher," he said.
"The science justifies action now by all countries to both adapt to climate change and to reduce greenhouse gas emissions."
© 2006 Independent News and Media Limited