As record-breaking scorching temperatures persist across Australia, the country's Bureau of Meteorology notoriously added a new color to its weather forecasting map,—extending the range to 54ºC, or 129ºF, from the previous cap of 50ºC, or 122ºF. The new deep purple "dome of heat" swirls above South Australia. (WP, Jan. 8) Fire crews are battling hundreds of wildfires, with New South Wales hardest hit. (Reuters, Jan. 9) Authorities fear a reprise of the devastating brush fires of 2009. One fire broke out at the  the Australian Nuclear Science and Technology Organisation (ANSTO) research facility in Sydney's south, sparking fears of a radiation release before it was extinguished. (TVNZ, Jan. 8) If this had happened, it would have been a nice convergence of the climate crisis and the nuclear threat, as we noted two summers ago when the flooded Missouri River threatened to overwhelm the Fort Calhoun nuclear plant in Nebraska.

Meanwhile, the New York Times, Jan. 8 ran a story entitled "Not Even Close: 2012 Was Hottest Ever in US."

The numbers are in: 2012, the year of a surreal March heat wave, a severe drought in the Corn Belt and a huge storm that caused broad devastation in the Middle Atlantic States, turns out to have been the hottest year ever recorded in the contiguous United States.        

How hot was it? The temperature differences between years are usually measured in fractions of a degree, but last year's 55.3 degree average demolished the previous record, set in 1998, by a full degree Fahrenheit.        

If that does not sound sufficiently impressive, consider that 34,008 daily high records were set at weather stations across the country, compared with only 6,664 record lows, according to a count maintained by the Weather Channel meteorologist Guy Walton, using federal temperature records.

That ratio, which was roughly in balance as recently as the 1970s, has been out of whack for decades as the country has warmed, but never by as much as it was last year.

"The heat was remarkable," said Jake Crouch, a scientist with the National Climatic Data Center in Asheville, N.C., which released the official climate compilation on Tuesday. "It was prolonged. That we beat the record by one degree is quite a big deal."       

Danny Harvey, a University of Toronto professor specializing in global warming and climate change, speaking to the Toronto Star about the Australia fires, said: "As the Earth gets warmer, we expect the frequency and severity of wildfires to increase. If you look at trends in the U.S., Canada and Russia, they all show either more frequent or more severe fire in the past decade and they are correlated to temperatures."

This kind of bet-hedging is sadly de rigueur. Any implication that the fires or heat waves are "attributable" to climate change is seized upon by the denialist crowd as (irony of ironies!) "unscientific." But as we have already noted:

We are constantly being admonished that no single weather event can be attributable to climate change. But when taken together—the superstorms, this summer's crippling droughts in the Midwest, the disappearing Andean glaciers, receding Arctic sea ice cover, the Alaskan villages disappearing beneath the waves—whether these are attributable to climate change becomes a dramatically wrong question. Together, these phenomena are climate change. Asking if they are "attributable" to climate change is a classic example of missing the forest for the trees.

When will it become permissible to say this?