20 November 2009

Almost as bad as it gets

In terms of fire weather, most of the southeastern portion of Australia has seen conditions that are about as bad as they get over the past few days. The whole month of November has seen unprecedented levels of heat for late spring, but the last few days have been over the top throughout the area. There have been widespread areas with temperatures well in excess of 40 C. These temperatures are approaching or exceeding all-time, not just for spring, record-high maximum temperatures (and record high-minimum temperatures, too). It was 43C in Adelaide on Thursday, and temperatures were in excess of 45C in northern SA and western NSW. See this post for a description of the heat during the earlier part of the month; the third record heat wave in two years in some places. The last few days have been even hotter, but not as long-lived. Another bad day tomorrow in NSW, but afterward the weather should moderate for the next few days at least. Look for a full description of the event, with all the climatological details, in a Special Climate Statement from the National Climate Centre on Monday.

Of course, with the extreme weather comes the extreme fire danger. The graphic, from the ABC, shows the regions covered by the new 'catastrophic' fire danger rating (FFDI > 100) today (20 Nov). Conditions were similar yesterday, with a focus further to the west. In many ways, Australia has been fortunate this time around; there have been no Black Saturday-level fire events during this period. No massive loss of life, no city-razing fires. There have been numerous fires started by lightning across SA, southern QLD and NSW; a few homes have been destroyed but overall the damage has been minimal. A nice summation of the fires today can be found in this article from the ABC. The firefighters have done a good job at managing this situation to date.

Events of this nature strengthen the evidence for the reality of the impact of climate change. Sure, previous generations saw fire weather events of similar intensity, but not this frequently and not at this strong. Remember, it is not even the nominal start of summer yet. Stick your head and the sand and deny the evidence if you must, but this is our new climate. Yes, climate variability will still exist, and we will see years or perhaps even a decade where conditions moderate, but events of this nature will become more frequent and eventually the norm. Its a record now, but soon enough these conditions are likely to be our average, what we expect every year.

If it makes you feel better, tell yourself it's natural...the natural response to the enhanced climate forcing from increased CO2, land degradation and other human factors. We did it and we have to live with it. Are you ready?

No comments: