It must be reassuring for so many people to simply “believe” things. For some of us, we need to do the sums, to make sure we’re not being taken for dummies. This letter is triggered by a recent news item from Greg Hunt MP, in last week’s paper, conclusion of which was that the Green Army contingent for Phillip Island will be a whole 10 youth volunteers to plant forest. Mr Hunt wrote his ‘Direct Action Plan Policy’ in 2008 with a few updates in 2010. From p.18 – “Based on industry estimates, the planting of 20 million trees will require approximately 200 to 400 square kilometres of land area depending on the intensity, and can be delivered at a cost of around $5 per tree… the Green Army announced by the Opposition Leader Tony Abbott on January 14, 2010, with tree-planting…”
Plan/Policy objective is to plant forest, enough to be absorbing 15 Mtonne/year CO2 by 2020. According to chiefscientist.org.au, because of low fertility soils and rainfall, absorption rate of CO2 by forest is 0.5 to 2tonne/Hectare/year. Taking a mid-value of 1.0 t/Ha/y, this means an area of 15MHa to absorb 15Mtonne/year, which is 150,000km2 of land area and, at 1000 trees/Ha, 15 billion trees. Direct Action claimed 20M trees, at $5/tree amounts to $100M but summary on p.31 allocates just $50M, a $50M small mistake. Meanwhile, analysis here has shown, at $5/tree, $75B is needed, a $74.5B whopper of a mistake. The amount of 15M ton/year CO2 is only a small proportion of National GHG emissions, towards 630M ton/year or 27 ton/person/year. This makes us worst in the world. Also, despite huge fuss about how much more wealthy we all are, because of the mining boom, we’re not considered liable for any emissions from burning of exported coal, from which new wealth is derived. By the time the massive, new Galilee Basin is exporting coal from Abbott Point in the Great Barrier Reef, including liability for emissions from this coal, our score will be close to 100tonne/person/year.
From the book ‘Sustainable Energy – without the hot air’ David JC MacKay, Professor in the Department of Physics at the University of Cambridge – “The best plants in Europe capture carbon at a rate of roughly 10 tons of dry wood per hectare per year – equivalent to about 15 tons of CO2 per hectare per year – so to fix a European’s output of 11 tons of CO2 per year we need 7500 square metres of forest per person. This required area is twice the area of Britain per person. And then you’d have to find somewhere to permanently store 7.5 tons of wood per person per year! At a density of 500kg per m3, each person’s wood would occupy 15m3 per year. A lifetime’s wood – which, remember, must be safely stored away and never burned – would occupy 1000m3. That’s five times the entire volume of a typical house. If anyone proposes using trees to undo climate change, they need to realise that country-sized facilities are required. I don’t see how it could ever work.” If the above is not mind boggling enough, for Australia, with emissions per person, at 3 to 10 times worse than Europeans, doesn’t this make the whole Green Army and forest solution nothing more than a distraction, just 2 per cent of size of problem, with budget shortfall of $50M v $74.5B? No wonder the Coalition didn’t submit their costings to Treasury, well before election, per directive of John Howard. Sometimes every little helps. At other times, every little just gets headline news, causing confusion and worsening the problem. Finally, why call young tree planters an army? Who’s the war against this time?
Bernie McComb, Cowes.