Australia endured its third-wettest year on record in 2011 as the disruptive La Nina weather pattern brought epic floods to the country, the Bureau of Meteorology says.
The bureau said Australia experienced one of its strongest La Nina effects, a phenomenon linked to both flooding and drought, on record in 2010-11 and then a second La Niña developed in late 2011.
“Back-to-back La Niña events led to a two-year rainfall total of 1,402 millimetres which is the second-highest total on record behind 1,407 millimetres in 1973-74,” the bureau said in its annual climate report.
Total mean rainfall in 2011 was 699 millimetres — well above the long-term average of 465 millimetres, it said.
Much of eastern Australia was flooded in early 2011, with torrential rains pounding parts of Queensland and Victoria, causing more than 30 deaths as they swept away homes and brought Brisbane, the country’s third largest city, to a standstill.
For the first time in a decade the country’s annual mean temperature was below the 1961-1990 average of 21.81 degrees Celsius, coming in 0.14 degrees below the mark.
“This was the first time since 2001 (also a wet, La Niña year) that Australia’s mean annual temperature was below the 1961-90 average,” the report said.
In contrast, the global mean temperature in 2011 was the highest for any year which began with a La Niña, a phenomenon characterised by unusually cool ocean surface temperatures in the central and eastern tropical Pacific.
Despite the cooler 2011, the bureau said Australia’s 10-year average continued to demonstrate a rising trend in temperatures, with 2002-2011 likely to rank in the top two warmest 10-year periods on record.
- Times Live
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