Climate change will hit Australia harder than rest of world, study shows
Science agency the CSIRO and Bureau of Meteorology predict temperature rises of up to 5.1c in Australia by 2090 in their most comprehensive forecast yet Australia could be on track for a temperature rise of more than 5C by the end of the century, outstripping the rate of warming experienced by the rest of the world, unless drastic action is taken to slash greenhouse gas emissions, according to the most comprehensive analysis ever produced of the countrys future climate. The national science agency CSIRO and the Bureau of Meteorology have released the projections based on 40 global climate models, producing what they said was the most robust picture yet of how Australias climate would change. The report stated there was very high confidence that temperatures would rise across Australia throughout the century, with the average annual temperature set to be up to 1.3C warmer in 2030 compared with the average experienced between 1986 and 2005. Temperature projections for the end of the century depend on how deeply, if at all, greenhouse gas emissions are cut. The world is tracking at the higher emissions scenario, meaning a temperature increase of between 2.8C and 5.1C in Australia by 2090. According to the report, this business-as-usual approach to burning fossil fuels is set to cook Australia more than the rest of the world, which will average a temperature increase of 2.6C to 4.8C by 2090. Australias surface air temperature has already increased 0.9C since 1910, with the number of extreme heat records outnumbering extreme cool records nearly three to one since 2001. Australia experienced its third-warmest year on record in 2014 , with 2013 its warmest year on record . The heat experienced in 2013 was unlikely to have been caused by natural variability alone, the report stated, with such temperatures now five times more likely due to humans releasing greenhouse gases into the atmosphere. Other findings of the wide-ranging analysis, the first such Australian climate projection made since 2007, included: These changes are likely to produce some benefits, such as enhanced agriculture in Tasmania and fewer deaths from cold weather. But they will be overshadowed by the negatives, such as rising numbers of deaths from heatwaves, water resource challenges, impacts upon agriculture and risks posed to coastal infrastructure by rising seas. Some of the most profound transformations are set to take place in the seas that surround Australia, which will warm by a further 2C to 4C unless emissions are cut. Excess carbon dioxide absorbed by the oceans causes the waters pH level to drop. This acidification makes it more difficult for corals to form hard reef structures and other creatures such as oysters, clams, lobsters and crabs to develop their shells. This phenomenon poses a major risk to ecosystems such as the Great Barrier Reef and is, according to the report, likely to impact the entire marine ecosystem from plankton at the base to fish at the top. Kevin Hennessy, a principal research scientist at the CSIRO, said it and the Bureau of Meteorology now had a greater confidence than ever in their forecasts of Australias climate. We expect land areas to warm faster than ocean areas, and polar regions faster than the tropics, Hennessy told Guardian Australia. Given Australias geographical position, that would mean much of the country was expected to warm faster than the global average. Australia will warm faster than the rest of the world, Hennessy said. Warming of 4C to 5C would have a very significant effect: there would be increases in extremely high temperatures, much less snow, more intense rainfall, more fires and rapid sea level rises. Hennessy said even the internationally agreed limit of 2C of warming on pre-industrial times would cause severe problems for Australia. That intermediate emissions scenario would have significant effects for Australia, he said. Coral reefs are sensitive to even small changes in ocean temperature and a 1C rise would have severe implications for the Great Barrier Reef and Ningaloo reef. The situation is looking grim for the Great Barrier Reef unless we can significantly reduce greenhouse gas emissions. A 2C future would be very challenging. Hennessy said Australia should prepare for this altered climate by ensuring hospitals, transport infrastructure, construction codes and fire planning all considered the rising temperatures. Cutting emissions would also help head off the worst of climate change, with nations set to convene in Paris later this year for crunch talks aimed at agreeing emissions reductions beyond 2020. Achieving that intermediate, rather than higher, emissions path would require significant reductions in global greenhouse gases, Hennessy said. Its difficult to say what will be achieved, there are a lot of negotiations to come in Paris. We hope there will be an agreement until 2050 at least, but who knows what will happen in the coming decades.