Key Factor #3: The Unique Role of Soils

The world has 10 years to take meaningful action that makes a difference in the trajectory towards climate chaos it is following, according to Sir Nicholas Stern and NASA’s James Hansen. (20)

The Legacy Load is a term we coined to describe the existing CO2e overload already in our atmosphere (from 200 years of excess emissions) which is enough to drive the global mean temperature through the critical 2°C level.

The concept of the Legacy Load is widely accepted by Climate Change leaders:

• "Twenty-first century anthropogenic (human) carbon dioxide emissions will contribute to warming and sea level rise for more than a millennium, due to the timescales required for removal of this gas.” Chair of IPCC Rajendra Pachauri, Yahoo News, 25 January, 2007

• “The carbon dioxide that’s in our atmosphere today – even if we were to stop emitting it tomorrow – would live for many decades, centuries and beyond,” said Dr Susan Solomon, senior scientist of the of the Global Monitoring Division of the U.S. National Oceanic and Atmospheric Administration.

• “A fraction of the carbon dioxide that we’ve put into the atmosphere today due to human activity would still be there in 1,000 years.” Global Response to Ozone Hole Is "Unprecedented" Success, Cheryl Pellerin The United States Mission to the European Union, August 24, 2006

• “Even if humanity were to stop emitting carbon dioxide today, temperatures will keep rising and the impacts keep changing for 25 years.” Sir Richard King, Britain’s Chief Scientist, The Age, 4 June, 2006

• “Much of the climate change likely to be observed over the next few decades will be driven by the action of greenhouse gases already accumulated in the atmosphere.” Climate Change: Risk & responsibility, Final Report, Australian Greenhouse Office, Department of the Environment and Heritage, March 2005

None of the popular solutions to Climate Change – including solar and wind power, thermal and nuclear, biofuels and waste management – can address the Legacy Load of GHG already loose in the atmosphere. Photosynthesis is the only process known to science that can soak up this load. Forests are incapable of doing the job for several reasons:

a. there is not enough land suitable for planting enough forests to reach critical mass;
b. most forest species are net emitters for the first 5-15 years;
c. it would take more than 20 years to plant and grow the forests to critical mass anyway;
d. it would be prohibitively expensive; and
e. it would take seven planet earths covered with forests to do the job . (21)

Only agricultural soils have the capacity and capability to absorb the Legacy Load for the following reasons:

• There are 5.5 billion hectares of agricultural land that can start sequestering Carbon with relatively small changes in management to unlock their potential.

• If the world’s farmers were able to sequester 0.5t/C/ha/year, they could absorb close to 2tonnes CO2e/ha/year – or 11gigatonnes of CO2e. This is more than the excess CO2e emitted by the entire world.

• Soil already holds more carbon than the atmosphere and all the forests of the world combined. Soil organic carbon is the largest reservoir in interaction with the atmosphere. Vegetation 650 gigatons, atmosphere 750 gigatons, soil 1500 gigatons. (22)

No matter what it lacks in terms of formal qualifications, agricultural soil is the only option the world has if it wants to take meaningful action in the short term to mitigate Climate Change and avoid the worst outcome.

The IPCC scientists continue to report that the effects of global warming are happening faster than predicted previously and that global emissions levels are rising faster than can be managed with existing strategies.

Only soils are equipped with the capacity and capability to answer the challenge of the moment.

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FOOTNOTES

(21) Tim Cadman, forestry researcher at the University of Tasmania: "We don't have enough land to make up for all our emissions; you would need seven planets." Sydney Morning Herald “A green response or just a guilt trip?” 27/01/2007

(22) (United Nations Food & Agriculture Organisation) -