The Australian Bureau of Meteorology (BOM) has released a detailed analysis of the 2009 southern Australian heatwave. Some of the figures presented are staggering, with numerous temperature records smashed. Indeed, a colleague at BOM pointed out just how exceptional this event was:
“Given that this was the hottest day on record on top of the driest start to a year on record on top of the longest driest drought on record on top of the hottest drought on record the implications are clear...
It is clear to me that climate change is now becoming such a strong contributor to these hitherto unimaginable events that the language starts to change from one of “climate change increased the chances of an event” to “without climate change this event could not have occured”.
I couldn’t have said it better. With the shifting climate we are rapidly moving into uncharted territory with unknown return times (but surely already well above what the long-term records might lead us to expect).
My sincere condolences also go out to the people whose family members or friends were killed the shockingly severe bushfires that followed these unprecedented ‘tinderbox’ conditions. I note that BOM will be releasing further updates in due course on the fire weather aspects of the event.
Some particularly interesting snippets from the BOM report, entitled “SPECIAL CLIMATE STATEMENT 17: The exceptional January-February 2009 heatwave in south-eastern Australia“:
On the morning of 29 January, an exceptional event also occurred in the northern suburbs of Adelaide around 3 a.m. when strong north-westerly winds mixed hot air aloft to the surface. At RAAF Edinburgh, the temperature rose to 41.7°C at 3.04 a.m. Such an event appears to be without known precedent in southern Australia…
The January-February 2009 event has now been responsible for seven of the eight highest temperatures on record in Tasmania; a total of eight sites reached 40°C, a mark which had only been reached on 16 previous occasions in the state’s recorded history…
On 7 February (Figure 2), the focus of the most extreme heat, which was accompanied by high winds and very low humidity, was in Victoria. An all-time state record was set at Hopetoun, in the state’s north-west, when the temperature reached 48.8°C, exceeding the old record of 47.2°C, set at Mildura in January 19395 by a considerable margin. Seven other sites, in the Wimmera and in the area immediately west of Melbourne, also exceeded the old record, including Avalon Airport (47.9°C), Horsham (47.6°C), Longerenong (47.6°C) and Laverton (47.5°C). The Hopetoun temperature is also believed to be the highest ever recorded in the world so far south. A total of 14 sites exceeded the previous Victorian February record of 46.7°C…
Many all-time site records were also set in Victoria on 7 February, including Melbourne (154 years of record), where the temperature reached 46.4°C, far exceeding it’s previous all-time record of 45.6°C set on Black Friday (13 January) 1939. It was also a full 3.2°C above the previous February record, set in 1983. Three of Melbourne’s five hottest days have now occurred during this event. Geelong (47.4) and Wilsons Promontory (42.0) were among long-term sites which broke all-time records which had been set only the previous week. In total, of the 31 currently open sites in Victoria with 30 years or more of data which reported on 7 February, 21 set all-time records, five set February records, and only five failed to set records at all. 7 Record high temperatures for February were set over 87% of Victoria…
Both Adelaide and Melbourne set records for the most consecutive days above 43°C. Adelaide’s temperatures were at this level on each of the four days 27-30 January, and Melbourne’s for three days from 28-30 January, breaking the previous records of two at both locations… Adelaide ultimately had nine consecutive days above 35°C; after never having experienced more than eight consecutive days above 35°C before March 2008, it has now happened twice within twelve months…
Melbourne had no measurable rain from 4 January to 7 February, the equal second-longest dry spell on record for the city (35 days). This approaches the record of 40 days set in 1954-55. Melbourne (0.8 mm) had its second-driest January on record, and with only 2.2 mm to 8 February has now experienced its driest start to a year on record…
Second, Dr Andrew Glikson has written an open letter to the Prime Minister, once again reiterating the urgency of the climate emergency. I have to ask (rhetorically I suppose), what will it take for the politicians to switch modes, from the awfully clichéd ”Climate change is happening, but let’s move slowing in doing anything meaningful about it so as to protect X, Y and Z [insert your favourite short-term political issue]” to the realistic “This is an emergency!”. I dunno. Let’s just hope it doesn’t take too many more disasters, such as this heatwave and its manifold consequences, or the crossing of Earth system tipping points such as the Arctic sea ice loss, to trigger the full-scale ‘war footing’ that is now so desperately required.
OPEN LETTER TO THE PRIME MINISTER OF AUSTRALIA
Dear Hon Kevin Rudd, MP, Prime Minister of Australia
A WARNING FROM THE PAST CLIMATE HISTORY OF EARTH
In his letter to you of 27 March, 2008, Professor James Hansen, leading US climate scientist and chief scientist of NASA’s Goddard Institute of Space Research (http://www.aussmc.org.au/Hansen_letter_to_Rudd.php), wrote, among other:
“Global climate is near critical tipping points that could lead to loss of all summer sea ice in the Arctic with detrimental effects on wildlife, initiation of ice sheet disintegration in West Antarctica and Greenland with progressive, unstoppable global sea level rise, shifting of climatic zones with extermination of many animal and plant species, reduction of freshwater supplies for hundreds of millions of people, and a more intense hydrologic cycle with stronger droughts and forest fires, but also heavier rains and floods, and stronger storms driven by latent heat, including tropical storms, tornados and thunderstorms”
Since this letter was written new research demonstrates the Earth’s atmosphere is more vulnerable to the rise in trace greenhouse gases, which regulate its temperatures, than we wish to believe, and that such rises in the past resulted in extreme shifts in the state of the atmosphere, oceans and biosphere, triggering mass extinction of species. Examples of some of these papers:
The new findings indicate that targets considered in the Garnaut Review, namely 450 ppm or 550 ppm CO2, can not be sustained. This is because carbon cycle feedbacks, including looming methane emissions, and the dynamics of ice/warming melt water interactions, threaten runaway warming leading toward tipping points, as occurred repeatedly in the past.
Current atmospheric CO2 levels (387 ppm) are already in the danger zone, while carbon gas emissions proceed at high rates (2.2 ppm in 2007; 1.8 ppm in 2008). It emerges that, unless simultaneous efforts are made to sharply cut carbon emissions and develop the technology for down-draw of atmospheric CO2, the future of our young and future generations looks grim.
The Greenland and Antarctic ice sheets formed under atmospheric conditions at, or below, 450 parts per million, which continued emissions and feedbacks will reach within a couple of decades, leading to temperature increases above 2 degrees C, advanced ice melt and metres-scale sea level rise.
Large mammals can hardly exist on land on an ice-free Earth, nor can human civilization survive such conditions.
In the wake of your election commitment to evidence-based policies (http://www.onlineopinion.com.au/view.asp?article=8049) you were given a historic opportunity to lead the world by example in relation to what you have correctly described as the great moral challenge of our generation (http://www.alp.org.au/labortv/uKTHPU1yia), through conversion of a coal-intensive highest per-capita carbon-emitting economy into an alternative energy-based system.
This could tilt the scales in an increasingly desperate global effort to avert what has been recently described by John Holdren, Obama’s new chief science advisor, as the global climate disruption (http://www.climatesciencewatch.org/index.php/csw/details/holdren_global_climate_disruption/)
Less than one year elapsed since Hansen’s letter was sent, and while isolated weather events are not necessarily related to climate change, a dangerous trend has developed consistent with projections of atmospheric science, relegating southern Australia to droughts and fire and the north to intense cyclones and floods.
Given the gravity of the matter, I suggest you consider to urgently convene a climate summit, where your government can listen to reports of severe climate disruption around the globe and in Australia, and to what the science says regarding future generations your government was entrusted to protect.
Honorable Prime Minister, as communicated by James Hansen, your leadership is required (http://www.aussmc.org.au/ Hansen_letter_to_ Rudd.php). I hope this will happen in the spirit of Dietrich Bonhoeffer (http://www.abc.net.au/rn/ religionreport/stories/ 2006/1755084.htm).
(Dr) Andrew Glikson
Earth and paleo-climate scientist
Australian National University
9 February, 2009