The short term, make-or-break role of soil carbon is as ‘a bridge to the future’, as depicted by the world’s most eminent soil carbon scientist, Dr Rattan Lal. Lal and his colleagues believe that carbon farming can stall Global Warming: “The technical potential of carbon sequestration in world soils may be 2 billion to 3 billion mt per year for the next 50 years. The potential of carbon sequestration in soils and vegetation together is equivalent to a draw-down of about 50 parts per million of atmospheric CO2 by 2100.”[1] This would enable mankind to keep CO2 levels below 450 parts per million and consequently hold global mean temperature from rising through the dangerous 2°C level. Dr Lal declares that. this process is immediately available, requiring a low cost change in land management practices across the world’s 5 billion hectares of farm land.“C sequestration in terrestrial biosphere (e.g., forests, agricultural soils) is considered a low-hanging fruit, a win-win strategy, and a bridge to the future until low-C or no-C fuel sources take effect.”[2]
Lal’s declaration is supported by America’s most prominent climate scientist, NASA’s James Hansen who said: “A reward system for improved agricultural and forestry practices that sequester carbon could remove the current CO2 overshot… A 50ppm draw down via agriculture and forestry practices seems plausible.”[3]
Australian scientists are recognising that the world has no credible alternative in the short term. The Wentworth Group of Concerned Scientists declared: “It will be next to impossible for Australia to achieve the scale of [emissions] reductions required in sufficient time to avoid dangerous climate change unless we also remove carbon from the atmosphere and store it in vegetation and soils.”[4]
The CSIRO acknowledges the phenomenon: “[W]hat [soil carbon sequestration] actually gives us is time to make those adjustments,” according to the CSIRO’s Dr Michael Battaglia.[5]
[1] RATTAN LAL, “The Potential for Soil Carbon Sequestration” in Agriculture and Climate Change: An Agenda for Negotiation in Copenhagen, International Food Policy Research Institute, 2009.
[2] RATTAN LAL, Editorial / Soil & Tillage Research 96 (2007) 1–5
[3] Hansen, J., Mki. Sato, P. Kharecha, D. Beerling, R. Berner, V. Masson-Delmotte, M. Pagani, M. Raymo, D.L. Royer, and J.C. Zachos, 2008: Target atmospheric CO2: Where should humanity aim? Open Atmos. Sci. J., 2, 217-231
[5] DR MICHAEL BATTAGLIA, THEME LEADER, SUSTAINABLE AGRICULTURE FLAGSHIP, CSIRO, Inquiry into Soil Carbon Sequestration in Victoria, Environment and Natural Resources Committee, Parliament of Victoria, September 2010
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