Wednesday, March 18, 2009

Outside of the Vortex

Parts of Australia are experiencing unprecedented changes in temperature and rainfall patterns. These changes are associated with an unexpected phenomenon emerging in the Indian Ocean and also in the behaviour of the Antarctic Vortex combined with steadily increasing temperatures from rising greenhouse gases and the depletion of the ozone layer. Observed together they suggest the very strong possibility that Australians are now facing abrupt climate change.[1] This is bringing very prolonged drought and extraordinary heat to the most heavily peopled and treed (mostly Eucalypt) regions of the country. As if this prospect is not frightening enough, it can be seen that climate is not the only threshold that is being crossed. The flashpoint for eucalypt vapour is also being breached by high daytime temperatures. This appears to guarantee the setting off of huge fire infernos in these semi-urban ‘forests’ on a scale that many would simply not be able to imagine.

Southeast Australia has been suffering from a drought over the last 15 years that is of an intensity that has not (as far as we are aware) been experienced before. This has left the landscape very dry. Climatologist Caroline Ummenhofer, a research fellow with the University of New South Wales says that “normally drought conditions over eastern Australia are associated with El Nino, La Nina cycles in the Pacific Ocean (temperature changes that affect the rainfall and circulation over the whole Pacific Ocean and the surrounding areas).” [2]

However, “El Nino is not able to explain this latest drought” says Ummenhofer. “Instead what we found is actually that the cause lies in Indian Ocean temperatures.” “The Indian Ocean has a similar phenomenon to the El Nino, La Nina cycle. It's called the Indian Ocean Dipole, and it's a naturally occurring phenomenon and has been known for some time to influence Australian climate and Australian weather. The dipole oscillates between positive and negative phases and has neutral years in between as well, so the negative and the positive are the two extremes. And the normal wet conditions that you experience over south-east Australia are linked to the negative Indian Ocean dipole event which we haven't seen over the last seventeen years…..the last India Ocean Dipole event of the negative phase occurred in 1992. That is unusual. We haven't anywhere in the record over the last 120 years that we've investigated seen a similarly prolonged period without a single negative event”

Ummenhofer observes that most of the world’s oceans are getting warmer, but particularly the Indian Ocean. “There might be indications that this could lead to changes in the characteristics of Indian Ocean dipole events.” [3]

The Antarctic Vortex near the South Pole is, like its equivalent in the Arctic pole region, a persistent, large-scale cyclone in the middle and upper troposphere and the stratosphere. Polar vortexes are most powerful in the hemisphere's winter, when the temperature gradient is steepest, and diminishes or can disappear in the summer. [4]

The Intergovernmental Panel on Climate Change Third Assessment Report incorporated a chapter [5] on ‘radiative forcing’[6] which noted “several … anthropogenic [man-made] causes for global climate change” These factors, that could be interacting with each other, including rising concentrations of greenhouse gases, the effects of man-made particulates in the atmosphere, and ozone depletion in the stratosphere.

The IPCC noted that scientific studies on these ‘forcings’ observed that the radiative effects of aerosols circulating in the atmosphere, whilst being largely confined to the Northern Hemisphere, may “propagate into the Southern Hemisphere via atmospheric dynamics”. In addition to this, the polar vortex in both the north and south hemispheres were strengthened and the westerly winds in the mid latitudes were contracting and thus moving closer to the poles. These changes, the report noted, may be arising from the rising greenhouse gas concentrations as well as from ozone depletion in the stratosphere.

The implications behind the fact that the westerly winds are moving closer to Antarctica are quite frightening for Australians. “it appears the vortex is shifting gear, and is spinning faster and faster, and getting tighter. As it does it’s pulling the climate bands further south dragging rain away from the continent out into the southern ocean.” [7]. In short, it means that Australia’s unprecedented and horrific drought may not go away!

Climate (like other complex systems) does not behave in a simple linear fashion. That is, simple linear extrapolation is not always possible. Sudden changes in a regime (such as rainfall) can occur over wide areas. This is what’s happened over Australia, even before the 1992 Indian Ocean dipole shift and the contraction of the southern vortex. Around 1945 Australia’s summer half-year rainfall increased over large areas in the eastern part of the continent. However, in 1967-72 there was a sudden decrease in rainfall in south-west of Western Australia which has not reversed since. [8] “Now the same thing is happening to Melbourne.” In 2003 rainfall there had fallen by nearly 20% in the previous 7 years. [7] This dangerous pattern has continued and, at present, almost every mainland capital city is on increasingly severe water restrictions.

Similar examples of sudden changes in system behaviour often arise from an element of the system reaching a limit or threshold at which instability sets in, and the system moves into a new stable state. When the system is close to a threshold even quite small random events or trends can force the system into a different state. Distance from a threshold of this sort is a measure of system resilience or ability to cope with small variations in conditions (Scheffer et al., 2001). [9]

So, indeed it does look like Australia is going through abrupt and dangerous climate change right now.

One very important question comes immediately to mind. How resilient is Australia’s society and infrastructure now? Are they ready to deal with the biggest challenge in the nation’s history? After the most horrific fires ever recorded? After 15 years of intense heat and drought?

What other thresholds, apart from climate-related ones, are Australians dealing with? One critical and almost entirely overlooked threshold is the flashpoint for eucalyptus oil. “The flash point of a flammable liquid is the lowest temperature at which there can be enough flammable vapour to ignite, when an ignition source is applied.” [10] The ‘flash point’for the vapours that rise from Australia’s ubiquitous native trees is a mere 49 degrees Celsius. On Black Saturday this year [11] the temperatures, in the shade, were around 47 degrees Celsius. In the full sun, however, temperatures are about 5-6 Celsius degrees hotter!

Another threshold associated with industrial tree plantations is the level of fuel loads that are amenable to control by our fire departments. The Canberra fire chief reported, soon after that city’s plantation fires encroached and burnt out hundreds of houses in this urban environment, that the fuel load in tree plantations 3-7 years of age was the limit reached before the fires could be brought under control. [12]

Those individuals living in southern Australia have every reason – whether they know it or not - to feel horrified by their prospects for next summer and for many summers after that. After all, “the past decade has recorded the largest expansion ever in [Eucalypt niten and Radiata pine tree] plantation cover in this country” with an average annual planting of 76,000 hectares per year since 1997. [13],[14]. “The majority…is concentrated along the southern and eastern coasts, Tasmania and Western Australia.” [15].

Up until ‘Black Saturday’ Australians had been lulled into a false sense of security. Many families had no knowledge of the need for fire plans or of local geography as “ 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” approached. [16] Residents are largely oblivious to the enormous hazards the intense and ubiquitous plantings of Eucalypt and Radiata pine monocultures pose to their safety. Residents of the burnt out Victorian township of Marysville saw “what looked like an atomic bomb”[17] coming over the top of the town but had no idea as to the nature of its genesis.

But the truth is that the Black Saturday fires entailed the convergence of two huge fire balls that erupted in a tree plantation estate at East Kilmore and joined with another fire front that appeared to begin at a timber mill in the Murrindindi complex of heavily logged native forest and extensive industrial tree plantations further east [18] [19]. “A two-kilometre stretch of power line in Kilmore East … snapped during strong winds and record heat about 11am last Saturday [7th February 2009]. Within minutes a nearby pine forest was ablaze. Within six hours the fire had destroyed nearly every building in the towns in its path….”[20] . Around 4pm the Victorian Country Fire Authority (CFA) had advised the public that “the fire [was] gaining strength as it head[ed] towards pine plantations near Wandong” [21]where a large bluegum plantation lay within a kilometer of the town. [22] Within 12 hours an ominous line of closely spaced fire fronts stretched all the way from very large East Kilmore/Murrindindi merged inferno through the Bunyip State Forest down to Druoin and Warragul; to within approximately 40 kilometres of the other very large fire complexes around Churchill. The Churchill fire, in turn, began one kilometre south-east of the town in a pine plantation. The flames, out of control, spread rapidly, threatening communities in Hazelwood South and the Jeeralangs. Traralgon South, Callignee, Woodside, Yarram, Carrjung, Gormandale and many more communities came under threat….”[23].

“We have seen the future” says Clive Hamilton. [24]. Some people ask whether Australians will continue to survive living within our tall Eucalypt forest digs. Perhaps the real forests will survive, though the trees may change; become stunted and sparse. With a few more fires the ugly industrial tree plantations will surely disappear. The surviving human residents will learn from the wombat and go underground.

[1] “…A working definition of 'abrupt climate change' is given in Alley et al. (2002): ‘technically, an abrupt climate change occurs when the climate system is forced to cross some threshold, triggering a transition to a new state at a rate determined by the climate system itself and faster than the cause’.

From: IPCC, AR4, WGI, Chapter 10 Global Climate Projections, Future Abrupt Climate Change, ‘Climate Surprises’, and Irreversible Changes.
As quoted in:
Abrupt Climate Change

[2] The El Nino Southern Oscillation (ENSO) is a particular pattern of disruption in the interaction between the ocean and the atmosphere that occurs every two to seven years when strong westward-blowing trade winds over the Pacific ocean subside and warm western Pacific water slowly moves back eastward. The upwelling of the cool, nutrient rich, eastern Pacific water (that supports large fish populations) is interrupted. When this happens fish die and climatic changes kick in that affect many parts of the planet. The possible interrelationship between El Nino and the simultaneous droughts on the Australian and other continents was first realized in 1972-73. See:
El Niño - Southern Oscillation (ENSO). Learning Module.

[3] Behind the big dry
Air Date: Week of February 13, 2009

[4] Polar vortex
From Wikipedia, accessed on 12th March 2009

[5] Houghton et al., 2001, Chapter 6. IPCC Third Assessment Report.

[6] “In climate science, radiative forcing is (loosely) defined as the change in net irradiance at the tropopause. "Net irradiance" is the difference between the incoming radiation energy and the outgoing radiation energy in a given climate system and is thus measured in Watts per square meter. The change is computed based on "unperturbed" values, as defined by the Intergovernmental Panel on Climate Change (IPCC) as the measured difference relative to the year 1750, the defined starting point of the industrial era. A positive forcing (more incoming energy) tends to warm the system, while a negative forcing (more outgoing energy) tends to cool it. Possible sources of radiative forcing are changes in insolation (incident solar radiation), or the effects of variations in the amount of radiatively active gases and aerosols present. Because the IPCC regularly assesses the radiative forcing, it also has a more specific technical definition - see "IPCC usage" section….”
Radiative forcing
From Wikipedia. Accessed on 18th March 2009

[7] Drought Vortex
18th September 2003
* Reporter: Karina Kelly * Producer: Andrew Holland * Researcher: Mark Horstman

[7] Drought Vortex
18th September 2003
* Reporter: Karina Kelly * Producer: Andrew Holland * Researcher: Mark Horstman

[8] (e.g., Deacon, 1953; Kraus, 1954; Gentilli, 1971; Pittock, 1975; Allan and Haylock, 1993). As quoted in ‘Climate Change: An Australian Guide to the Science and Potential Impacts’ Edited by Barrie Pittock. 2003.

[9] ‘Climate Change: An Australian Guide to the Science and Potential Impacts’ Edited by Barrie Pittock. 2003.

[10] What is the difference between <>& <> of a material ?

[11] Black Saturday: the day the worst bushfires in Australian recorded history broke out was on 7th February 2009.

[12] Interview ABC TV: ‘7:30 Report. Kerry O’Brien and Phil Koperberg, NSW Fire Chief. After the Canberra Megafire and its later inquiry, it was reported that to have any hope of ‘managing’ such a fire, fuel build up would need to be as low as 4-5 tonnes per hectare or less. This degree of fuel loading is apparently reached in plantations by 3-7 years.

[13] “The major funding channel funding the elevated planting program is via managed investment schemes” (MIS) which is a widely unpopular financial lurk comprised of billions of dollars of taxpayer subsidies, exemption from land planning and environmental laws. Exemption from landtax, lower local rates payments and extraordinary grants, taxpayer funded infrastructure and other extraordinary subsidies. All for a handful of chosen private corporations. See, for instance:
(i) The MIS anomaly is in land tax law’ by John Lawrence. Tas Country. Page 12. 16th January 2009. [John Lawrence is an economist working as an accountant in public practice.]
(ii) “The Weekly Times asked the tax office in the past why it allowed MIS companies to charge more than $9000 a hectare to establish blue gum plantations, when it cost the non-MIS sector $3000/ha...”

End MIS Excesses of the Past
January 7, 2009
(iii) MIS raises hackles by Matilda Abey. January 9, 2009

(iv) for a more complete list see the archives of the Tasmanian Times:

[14] “The schemes raised more than $1.01 billion in 2004-5 [alone] despite wide spread drought conditions.”
Growing the Forestry Enterprise in Australia
Gary Bacon, Centre for Forestry and Horticultural Research, Griffith University. 18th April 2007

[15] Australian forest plantations – a review of ‘Plantations for Australia: the 2020 vision’. Rural and Regional Affairs and Transport Reference Committee. Senate Committee Report. Page 5. September 2004.

the heatwave in Australia on 7th February 2009:

[17] ‘Blithe Oblivion’ by Kate Legge. The Weekend Australian Magazine. 7-8th March 2009. Page 20.

[18] Kilmore East Murrindindi Complex fire map. 3rd March 2009

[19] Fire/land tenure map of the Murrindindi fire that burnt through Marysville overlaid onto the latest NASA satellite Infrared Image.25/02/2009 8:46 am

[20] Huge fire class action launched
* Cameron Houston and Michael Bachelard
· February 15, 2009

[21] Townships under ember attack as fires rage
ABC - February 7, 2009, 4:18 pm

[22] Bluegums within a 1 km of Wandong.
Google Earth Image Circa April 2005 of Midway Wandong Plantations. Sunday Creek, Pine Creek and Dry Creek catchments.

[23] Churchill and District News. February 2007

[24] Bushfires: Don’t mention the c word. Clive Hamilton

1 comment:

Neil Cameron (One Salient Oversight) said...

There IS something really screwy going on.

The Southern Oscillation Index has been broadly positive for some 2 years now, while the Eastern Pacific is cooler than average.

Of course we are in a La Nina, but by rights we should be having lots of rainfall. We're not (at least not south of Gladstone).