Certainly, the world appears to have increasingly suffered wild and damaging swings in its weather in recent years, from the record high temperatures and bushfire havoc of Black Saturday in February 2009 to monsoonal flooding in January 2011, from scorching Russian summer to recently snowbound Europe and North America.
Global reinsurance giant Munich Re recently plotted 950 natural catastrophes over 2010. It found more than 90 per cent were weather-related - with a cost of more than $US130 billion and a huge loss of life. It estimated the Russian heatwave and associated fires and air pollution in July killed at least 56,000 people and Pakistan’s worst-ever floods killed 1769.
Worldwide, 2010 was the wettest on record but, according to the World Meteorological Organisation, also the hottest since instrumental climate records began in 1850. Eighteen nations experienced their hottest-ever temperatures. It was the coolest year in Australia since 2001 but still above the long-term average.
Professor Nicholls says that while it is not possible to accurately predict global warming-induced changes to natural variables like La Nina, one prediction can be made with confidence - heatwaves.
”The last 10 years has been the decade of unprecedented heatwaves around the world,” he says. ”A whole string of heatwaves much more dramatic than we’ve seen before and they’ve been killer heatwaves.”
The last three days of January 2009, in the week before Black Saturday (at 46.4 degrees, itself the hottest February day in Melbourne by more than three degrees) there were 374 extra deaths in Victoria due to the heatwave, he says.