BROOK, BARRY. Professor Brook: “the real goal is 300 ppm”

Professor Barry Brook holds the Sir Hubert Wilkins Chair of Climate Change and is Director, Research Institute for Climate Change and Sustainability at the University of Adelaide (see: http://www.adelaide.edu.au/directory/barry.brook and www.adelaide.edu.au/climatechange ) See also his superb, informative and authoritative “Brave New Climate”: Blog: www.bravenewclimate.com ).

Professor Barry Brook:: “If the planet is like an oven, it's still possible to turn down the temperature. The number is 300 and the methods will be extraordinary. In 2007, a climate awareness campaign was launched by well-known environmental author Bill McKibben. It was coined 350.org, with the slogan "350 is the most important number on the planet". The figure refers to a target concentration of carbon dioxide (CO2) in the Earth's atmosphere, in parts per million (ppm). This number was drawn from a recent study by a team of climate scientists, led by NASA's Dr James Hansen ... But there is another, more surprising, problem with 350. It's the wrong number. While 350 ppm should give us a reasonable shot at avoiding more than two degrees of warming, that's hardly a safe future to be aiming for. We need only to look at the impacts at less than one degree to know we're already committed to some tough adaptation problems … A target of 300 to 325 ppm CO2 - the levels of the 1950s - is necessary if we wish to cut additional warming and start to roll back the already damaging impacts. As such, 350 is not a target, it's a signpost to a goal. So we're aiming at 350 but the real goal is 300 and we're already at 385”. [1, 2].

[1]. Professor Barry Brook, “Six degrees of separation”, Sydney Morning Herald, 23 March 2009: http://www.smh.com.au/environment/earth-hour/six-degrees--of-separation-for-the-planet-20090324-984c.html .

[2]. Professor Barry Brook, “BraveNewClimate.com: http://bravenewclimate.com/ .