So how wet was Australia in 2010 and 2011? Wet enough, it turns out, to reverse the climb of global sea levels in a temporary shift that baffled scientists.

New research from the US shows the normally dry outback regions of Australia acted like a gigantic sponge, sending sea levels sinking until the water gradually made its way back to the oceans via evaporation or seepage from land.

Floods turned the Red Centre green. Credit:Dean Sewell

“For an 18-month period beginning in 2010, the oceans mysteriously dropped by about 7 millimetres, more than offsetting the annual rise,” the US National Science Foundation said in a statement before the release of a report to be published next month in the Geophysical Research Letters journal.

“In late 2010, early 2011, there was a whole series of flooding events in Queensland, in Victoria, in the Northern Territory – and then tropical cyclone Yasi hit northern Queensland,” said David Karoly, professor of meteorology at the University of Melbourne. “If you look at the area of Australia and the amount of water that fell, it's not surprising that it had an impact on global sea levels.”