2008 cooler, but world still warming
The past 12 months have been cooler than previous years but longer-term trends show the world is still warming due to climate change, according to a report from the World Meteorological Organisation.
"The global temperature is likely to rank around the 10th warmest year" on record, says World Meteorological Organisation (WMO) Director General Michel Jarraud.
"The trend for warming is still very much there," he says, noting that all the years that have been warmer than 2008 have been during the last 12 years.
The slight dip in 2008 was explained by the moderate-to-strong La Niña that developed in the latter half of 2007, he says.
The effects of El Niño and La Niña - respectively the warming and related cooling of Pacific sea surface temperatures - are felt in many parts of the globe.
They have been blamed for a lengthy drought in Australia, flooding in the Horn of Africa and Bolivia, and more severe winter monsoons in South Asia in 2006-2007.
Jarraud says both phenomena should be "neutral" in 2009 and should not have a discernible impact on climate.
But he is concerned that ice in the Arctic Sea dropped to its second-lowest level during the melt season since satellite measurements began in 1979. He notes that 2008 saw many devastating floods, droughts, heatwaves and storms, most notably Cyclone Nargis, which devastated Myanmar in May.
Jarraud says that it is too early to give any forecasts for 2009, but cites the most recent report from the UN's Intergovernmental Panel on Climate Change (IPCC) which predicted a 0.2% rise in temperature over the next decade.
Droughts and rain
The WMO report highlighted the record heatwave across southern Australia in March that brought scorching temperatures across the region.
Adelaide experienced its longest running heatwave on record, with 15 consecutive days of maximum temperatures above 35°C.
Despite that, Dr Andrew Watkins of the Australian Bureau of Meteorology says the results for Australia reflect the global picture.
"We had a La Niña event in the region, which results in cooler temperatures in Australia," he says.
"The national average was 0.37°C above the 1961-1990 average, which makes it the 15th warmest on record."
But Watkins says Australia's average temperature continues to display an upward trend, with 2008 being the warmest La Niña year ever recorded.
He says rainfall across Australia was "a mixed bag".
Central Australia and southern Victoria experienced below average rainfall - the later recording its ninth driest on record.
"The story for southern Australia is that it was a dry autumn and a very dry start to spring," says Watkins. "That meant we had a very dry start to the cropping season and the end, which has a significant impact."
Watkins says forecast models suggest rainfall patterns for the next few months to continue recent trends.
"There is the probability of above median rainfall in south-western Australia, southeast Queensland and northern New South Wales, which will be a continuation of what we have already been seeing," he says.
Watkins says it is too difficult to predict what will happen next year, but a number of indicators suggest normal conditions or another La Niña event.
But he warns that the upward trend in average temperature will continue.
"The long term trend for Australia and the globe suggests it will still be above average."