Australian heat wave pressuring commodities

SYDNEY - Australia can expect even longer and hotter heat waves than the one now scorching wide swathes of the country, a climate research group said on Thursday, raising questions about its long-term position as an agricultural powerhouse.

A blistering heat wave has settled over Australia's south and southeast for nearly a week, with soaring temperatures causing worry after players and fans alike collapsed at the Australian Open Tennis Tournament in Melbourne.

Temperatures on Thursday continued to rise, with the mercury in Melbourne set to tick over at 44 Celsius (111 Fahrenheit), two degrees higher than Wednesday when one player, Canadian Frank Dancevic, hallucinated the cartoon dog Snoopy before fainting during a match.

Adelaide's expected 46C, though, will earn the distinction of being the world's hottest city on Thursday, according to the UN World Meteorological Organisation.

The privately run Climate Council, which includes former members of a government-funded climate change watchdog shut by Prime Minister Tony Abbott's conservative government last year, warned in a report that Australia had only begun to feel the impact of climate change.

The heat wave, says the report's author, Will Steffen, follows the felling of a host of temperature records in 2013, including the hottest year on record.

"Australia has always had hot weather. However, climate change is loading the dice toward more extreme hot weather," Steffen said.

Prolonged heat waves would threaten Australia's agricultural production and undermine its policy of being the "food bowl of Asia", analysts said.

"It will be much harder to maintain production if you have such extreme weather events," said Paul Deane, senior agricultural economist at ANZ Bank.

"Higher temperatures tends to lead to more evaporation of any rain, all of sudden the water availability for crops is reduced, which will have a big impact on crops like wheat and sugar."