Greetings from the Australian National University in Canberra, where Professor Brendan Mackey, Director of the Griffith Climate Change Response Program, is asking "Does planting trees offset fossil fuel emissions?". Appropriately the talk is being held in the timber paneled forestry lecture theater. The talk is based on the paper “Untangling the confusion around land carbon science and climate change mitigation policy” (by Mackey, Prentice, Steffen, House, Lindenmayer, Keith and Berry in Nature Climate Change, 2013). To cut to the chase, they find that planting trees will not 'offset' emissions from burning fossil fuels. It is not that trees don't store carbon, it is just that the amount to be stored is too large. However, avoiding cutting down more trees would be useful for not further increasing emissions.
Professor Mackey commented this was his first presentation using Prezi. He apologized if this made us seasick, but it was a very clear and interesting visual presentation (much better than another dull Powerpoint slide show).
The issue of carbon emissions is not just an academic one for ANU. The ANU student newspaper has a lead article criticizing thee university for increasing its investment in coal seam gas mining (ANU Turns Up The Gas, Woroni", Ben Latham, No 7, Vol 65, Thu 16). Research by Southern Cross University suggests that far more methane is leaking from coal seam gas mining than previously expected (Fugitive Emissions from Coal Seam Gas, Santos and Maher, 2012). So it appears possible that coal seam gas increases global warming, not reduce it.