LONDON: The first decade of this century is “by far” the warmest since instrumental records began, say the UK Met Office and World Meteorological Organization.

Their analyses also show that 2009 will almost certainly be the fifth warmest in the 160-year record. Burgeoning El Nino conditions, adding to man-made greenhouse warming, have pushed 2009 into the “top 10” years. The US space agency NASA suggests that a new global temperature record will be set “in the next one or two years”.

World Meteorological Organization (WMO) and Met Office scientists have been giving details of the new analysis at the UN climate summit in Copenhagen. The WMO said global temperatures were 0.44C above the long-term average.

“We’ve seen above average temperatures in most continents, and only in North America were there conditions that were cooler than average,” said WMO secretary-general Michel Jarraud.

“We are in a warming trend — we have no doubt about it.” Jarraud emphasised that the final analysis would not be complete until early next year; but the UN agency always issues a summary during the annual climate negotiations in order that delegates have the latest information.

The WMO uses three temperature sets - one from the UK Met Office and the University of East Anglia’s Climatic Research Unit (CRU), and two from the US, maintained by the National Oceanic and Atmospheric Administration (NOAA) and the NASA.

Asked whether the controversy surrounding e-mails hacked from CRU could have any bearing on the results, Jarraud replied that all three datasets showed the same result.

Vicky Pope from the UK Met Office made the same point: “The datasets are all independent, and they all show warming,” she said.

The Met Office figures indicate that the years since 2000 — the “noughties” — were on average about 0.18C warmer than years in the 1990s; and that since the 1970s, each decade has seen an increase of about the same scale.

Although the Met Office has 1998 as the single warmest year, that coincided with strong El Nino conditions — the warming of surface waters in the eastern Pacific that releases heat stored in the deep ocean into the atmosphere, raising temperatures globally.

Another El Nino is developing; and it is this, combined with greenhouse warming, that is pushing temperatures upwards again.