This years Greenhouse 2009 conference in Perth held few surprises. The warming is worse than thought in the IPCC AR4, but until the Fifth Assessment Report (AR5) is out in 2014 little can be done through this process to spur governments to further action. On the other hand the scientific meeting in Copenhagen last week, in the lead up to COP15 this December, put out a statement detailing the increasing rate of change and the need for urgent action.
Many examples of effects of this more than expected rapid warming were given at the conference. While the scientists say it is often difficult to pick whether this is natural variability, the fact that observed measures are tracking along the IPCC A1FI (most carbon intensive SRES) scenario is of concern. The Australian Climate Change Science Program (CSIRO and the Bureau of Meteorology) had available a booklet Science Update 2009 issue one summarising recent relevant climate change science, with relevant references. It discusses the more recent than IPCC AR4 changes. Subscription can be made at
www.climatechangeinaustralia.gov.au.
Ross Garnaut described how the Great Recession interacts with this “time of decision” on climate mitigation, and he is pessimistic. Although the recession gives us a brief breathing space in emission increases, and an opportunity for structural reform with low opportunity costs, high unemployment and the new distrust for the market as a safe vehicle for managing change may impede effective action. He did make the point that private vested interests have had undue prominence and that those with the public interest at heart need to overwhelm these people.
Filippo Georgi from Aldus Salam International Centre for Theoretical Physics, Italy, presented on issues determining regional, in contrast to global, climate change modeling. It listed the sources of uncertainties that are inherent in the assumptions underlying and built into the models. In spite of these uncertainties massive work done with various ensemble runs of models over time have shown consistently:
Climate change will not be uniform; there will be regional hotspots at subcontinental scales and these are consistent in different models over time; southern Australia particularly in the west is such a spot;
There will be wide variation in climate / weather patterns between consecutive years at the same location;
Rainfall will in general be less frequent but more intense over land masses; and
Globally there will be increases in heatwaves over land.
The government and energy industry seem to think that business nearly as usual with minor tinkering will get us through. Chris Mitchell from the CO2 Group discussed barriers to reducing Australia’s greenhouse emissions which include:
A series of market and regulatory failures rather than a lack of technology, which by and large exists;
Serious complexity in ownership, governance and regulation, incompatibilities in technology and measurement, and lack of good research which all combine to make assessment, planning and decision making about energy options impossibly difficult.
Various industry and government representatives, both those seeking and those giving advice, are clear that they understand there are uncertainties with the science, but they accept the precautionary principle and want scientists to give them a best estimate on which they can begin planning.
Graeme Pearman, former CSIRO Atmospheric Division director and now consultant, emphasised the proposition that understanding and working with human behaviour is fundamental in working our way toward solutions to the uncertain, complex, urgent and inequitable problem that is climate change. He and other speakers discussed ideas for building resilience and sustainable communities to take us along this path. I will report on resilience and adaptation elsewhere.
From a long discussion about oceans it is clear that the problem with global warming and oceans is not sea level rise, but in fact ocean warming and acidification. Other issues pertaining to increases and decreases in salinity are also important. Essentially though climate changes are consequent to the warming of the oceans, which are the major heat sink. Second, as the major CO2 sink, the oceans are acidifying. This not only reduces many species capacity to calcify their shells, but more dangerously it has other effects on a wide range of biological processes necessary for life and reproduction.
Other more specific issues will be covered elsewhere.
To conclude, Graeme Pearman drew the analogy that there are about 6 billion pieces in a Boeing 747. This is roughly the same as the number of species on the planet that make up the ecosystem on which we rely for air, clean water, food and so on. If we were told that one or two (unidentified) pieces of the 747 had been removed we would probably still chose to fly in it. If, however we were told that a random 30% of pieces had been removed, we probably would not. The IPCC AR4 puts the projected likely loss of known species from our ecosystem with a 2 degree rise in temperature at about 30%. Do we still want to fly? Or turn down the thermostat?
