Australia’s hottest year on record in 2013 would’ve been “virtually impossible” without human-driven climate change, with the record temperatures made 2,000 times more likely due to greenhouse gases, research has found.
Four separate research papers into last year’s record heat have identified a distinctive human “fingerprint” on the series of highs, which included Australia’s hottest day, month, summer and spring since records began in 1910.
Researchers ran a number of simulations that looked at how 2013 would have unfolded without the influence of warming gases, such as those derived from burning fossil fuels.
Overall, the additional greenhouses doubled the chance of the most intense heatwaves, made extreme summers five times more likely and increased by seven-fold the chance of hot, dry drought-like conditions.
Specifically, the record heat of 2013 was “virtually impossible” without the influence of global warming, with greenhouse gases making the unprecedented temperatures 2,000 times more likely.
“When it comes to what helped cause our hottest year on record, climate change is no longer a prime suspect, it is the guilty party,” said Prof David Karoly of the University of Melbourne, who contributed to the research.
“Too often we talk about climate change impacts as if they are far in the future. This research shows they are here, now.”
Researchers from the University of NSW, University of Melbourne and the Australian National University (ANU) worked on the project for a special edition of the Bulletin of the American Meteorological Society.
More on www.theguardian.com/environment/2014/sep/30/greenhouse-gases-made-hottest-year-on-record-2000-times-more-likely