Record heat without an El Niņo: an unusual occurrence
Oz is winding down the hottest summer ever recorded. This is from Doctor Jeff Masters' blog
What's notable about the new summer heat record is that is occurred during a “neutral” period in the El Niño-Southern Oscillation (there was neither a La Niña nor El Niño event present.) El Niño conditions add an extra natural bump to temperatures over Australia, and it is difficult to set all-time heat records unless there's an El Niño present. Before 2013, the hottest three summers on record in Australia occurred during El Niño years. Breaking an all-time hottest month and hottest summer record during a non-El Niño year is the type of event that would be difficult to have in Australia without a warming climate.
Figure 2. The departure of temperature from average for Australia from 1910 - 2013 shows that summer temperatures have warmed by about 0.8°C (1.4°F.) Most of this warming has occurred since 1950. Image credit: Australian Bureau of Meteorology.
Global warming expected to make the summer of 2012 - 2013 seem cool by late this century
According to the Australian Bureau of Meteorology, "the most significant thing about all of these extremes is they fit with a well established trend in Australia--it’s getting hotter, and record heat is happening more often. Six of Australia’s ten hottest summers on record have come in the last eleven years, meaning that very hot summers have been occurring at about five times the rate you would expect without a warming trend. In the last decade, record high temperatures have outnumbered record low temperatures in Australia by a ratio of about three to one. About a third of the all-time record high temperatures at the Bureau’s long-term stations have occurred since 2000…Australia has warmed by nearly a degree Celsius since 1910. This is consistent with warming observed in the global atmosphere and oceans. And it’s going to keep getting hotter. Over the next century, the world will likely warm by a further 2 to 5 degrees, depending on the amount of greenhouse gases emitted into the atmosphere. Under mid-to-high emissions scenarios, summers like this one will likely become average in 40 years time. By the end of the 21st century, the record summer of 2013 will likely sit at the very cooler end of normal."
