GENEVA - The amount of greenhouse gases in Earth's atmosphere hit a new record high in 2012, continuing an ever-faster rise that is driving climate change, the UN weather agency said Wednesday.
"The concentrations are reaching once again record levels," Michel Jarraud, who heads the World Meteorological Organisation (WMO), told reporters in Geneva.
His organisation released its annual report on greenhouse gases Wednesday, showing that concentrations of carbon dioxide (CO2), methane and nitrous oxide all broke fresh records in 2012.
Global concentrations of CO2, the main culprit in global warming, for instance reached 393.1 parts per million last year, or 141 per cent of pre-industrial levels - defined as before 1750.
The report was released a day after the UN Environment Programme warned the chances of limiting the global temperature rise to two degrees Celsius (3.6 Fahrenheit) over pre-industrial levels were swiftly diminishing, and ahead of UN climate talks that open in Warsaw next week.
The UN's two-degree target is being chased through efforts to curb Earth-warming greenhouse gas emissions, mainly caused by fossil-fuel burning to power industry, transport and farming.
"The observations from WMO's extensive Global Atmosphere Watch network highlight yet again how heat-trapping gases from human activities have upset the natural balance of our atmosphere and are a major contribution to climate change," Jarraud said.
Dave Reay, a carbon management expert at the University of Edinburgh, said that stabilising greenhouse gas concentrations was the key to successful climate negotiations, emissions regulations, and carbon markets rests.
"Despite the financial crash, and reduced emissions from some nations, the global picture is one of carbon dioxide concentrations in our atmosphere reaching a record-breaking high year after year," Reay added.