Tania Tan, Straits Times 3 Apr 08;
THE weather last month may have called for sweaters, but make no mistake about it: Singapore is still sweltering in the heat of global warming, say experts.
Average temperatures dipped to a cool 26.5 deg C last month, making it the coldest March since 1990.
At its chilliest, the mercury dropped to 21.8 deg C due to the 'wetter than average' weather, said the National Environment Agency (NEA).
But despite the dip, a close tracking of temperatures over the last few years shows that the weather is getting hotter.
'I worry that people may forget the bigger picture,' said Associate Professor Matthias Roth of the National University of Singapore's department of geography.
'Even though we may have had a cool bout, it's important to realise that climate change is still happening.'
Since the 1970s, Singapore's average annual temperature has creptup from about 26 deg C to 28 deg C.
'This is in line with a global trend,' said the NEA.
Last month's lower temperatures were driven by freakishly wet weather. The rain was due to a pronounced La Nina effect, possibly the strongest since the 1970s, said Prof Roth.
Caused by a swirl of cooling air over the Pacific Ocean, the phenomenon usually results in cooler, wetter weather.
More than double the average amount of rainfall - up to 570mm - was dumped on some parts of the island in the first two weeks of last month, said the NEA's Meteorological Services Division.
Brief spells of heavy rain are expected to continue for the next two weeks as light and variable winds carry moist air in from the Pacific, said the NEA.
Asked whether climate change could be aggravating the La Nina effect, Prof Roth said scientists have yet to answer that question.
'It's still being debated,' he said.
But what is certain is that the planet is getting hotter.
In 2005, the United Nations Intergovernmental Panel on Climate Change concluded that the earth's surface temperature was likely to rise between 1 and 6 deg C by the end of this century due to greenhouse gases, which trap heat.
To help combat climate change, some countries, including Singapore, have tried to cut carbon emissions through recycling, increasing energy efficiency and reducing waste.