Australia’s changing climate
A new report, Climate Change in Australia, has just been released. Developed by CSIRO and the Bureau of Meteorology it provides the most comprehensive (and pretty scary) assessment to date of Australia’s future climate. Basically, Australians are going to be increasingly saying “it’s getting hot in here”. The report looks at the years 2030, 2050 and 2070 through the lens of a number of different greenhouse gas emission scenarios. Here’s the bad news:
- by 2030 temperatures will rise by about 1 ºC throughout Australia
- then it depends on the level of greenhouse gases as to what happens next, but….
- if emissions are LOW, warming of between 1 ºC and 2.5 ºC is likely by around 2070, with a best estimate of 1.8 ºC.
- but…if emissions are HIGH, then we’re stuffed – under a high emission scenario, the best estimate warming is 3.4 ºC, with a range of 2.2 ºC to 5 ºC.
- the number of days hitting 35ºC may triple
- the likelihood of seeing rain is pretty slim – under a low emission scenario in 2070, the best estimate of rainfall decrease is 7.5%. Under a high emission scenario the best estimate is a decrease of 10%.
And as a result of all this? well…..a long list of potential catastrophic scenarios:
- more frequent droughts particularly in south-west Australia (well, let’s just extend our current long drought straight through to 2070!)
- high-fire danger and more frequent bushfires
- more intense tropical cyclones
- rising sea levels.
You can freak yourself out with a climate change map of Australia here on the CSIRO site. The technical report is here if you want to wade your way through it. And if you live in Sydney, here’s the really bad, worst case scenario news – an annual temperature rise of up to 4.3 degrees by 2070. And we can’t panic now because it’s already too late to avoid a warming of about 1 degree by 2030.
The report highlights a warming of 0.9 degrees since 1950 and an increase in hot nights have been mostly due to greenhouse gas emissions. There’s been a 40% reduction in snow depth in Spring in the Snowy Mountains in the past 45 years.
And obvious signs of climate change are already happening at the top end of the world. In Greenland, in the year 985, Erik the Red, who was leader of a medieval Norse colony, built his farm and raised sheep, cattle, and barley. Erik and his cohorts could do this because the climate was warmer, but then the Little Ice Age arrived and the colony was doomed. Now, it’s come full circle – in Qassiarsuk, Greenland, young potatoes and radishes are sprouting up. Scientists say that nowhere else in the world are the effects of climate change so obvious as in Greenland. Winter sea ice is rapidly disappearing, which means the Inuit might be in for a rough ride – ice-hole fishing, sled dog mushing and other traditional means of living and surviving will disappear along with the ice. Farming, which is an occupation not heard of 100 years ago in this area, will stage a comeback due to warmer temperatures.