Don't be fooled by cold winters, study warns – Australia's still getting warmer
|
Version 0 of 1. Australians who have just experienced their coldest winters in decades shouldn’t be fooled, scientists say, with new research showing that new heat records are outnumbering new cold records at an accelerating rate. An analysis of 100 years of Australian temperature data has found that in the past 15 years, new records for heat outnumber those for cold by 12 to one, with human-induced climate change the primary factor. The study by the ARC Centre of Excellence for Climate System Science found that heat records roughly matched cold records between 1910 and 1960, before new highs of heat began to gain dominance. Scientists found that natural variations such as solar radiation, the periodic El Nino climate event and volcanoes would continue to deliver an equal split between hot and cold extremes in recent years. Only the added factor of heat-trapping gases in the atmosphere, caused by human activity such as burning fossil fuels, has tipped Australia towards hotter extremes. Related: Nature's last refuge: climate change threatens our most fragile ecosystem Warm weather has not been top of mind for most Australians living in the southern states this year, with Melbourne experiencing its coldest winter in 26 years and Tasmanians enduring the lowest temperatures in nearly 50 years. Meanwhile, Canberra has had its coldest winter since 2000. However, Sophie Lewis, lead author of the climate study, said that people have simply become used to warmer temperatures being the norm. “It’s been the coldest winter compared to a warm period, which means it’s just been cold in the context of recent warmth,” she said. “What we perceive as cold isn’t cold in a long-term context. We will still get cold records in the future, they will just be less likely. “This trend is consistent with the increase in greenhouse gases and the warming trend of the last century in Australia. As greenhouse gases increase, we should expect to see even more hot records in the future.” The study looked at the monthly and seasonal temperature records set in each state and nationally since 1910 to see work out the trend of how records were being broken. In 2013, Australia experienced its warmest year on record, including its warmest summer. Last year was Australia’s third warmest year on record, with scientists attributing a climate change “fingerprint” upon these recent warm years. Australia has warmed by around 1C over the past century, with the possibility of up to 5.1C warming by the end of this century without radical cuts to greenhouse gas emissions. Any temperature rise above 2C is likely to have major implications for Australia in terms of severe heatwaves, loss of agriculture due to drought and ocean acidification that will damage coral ecosystems such as the Great Barrier Reef. Lewis’ study found that nighttime temperatures have risen more sharply than daytime temperatures, with autumn warming more than summer. |