Tony Lovell on Soil Carbon: Putting Carbon Back Where It Belongs – In the Earth (TEDx video)

I love the nice progression of logic in this presentation. Running the numbers like this shows not only how powerful a carbon sink our earth’s soils can be, under the right management, but also just how futile and what a goose-chasing diversion most contemporary technological ‘fixes’ for climate change really are.

When you see the upwardly stepped red line (10:32) showing the seasonal rise and fall of CO2 concentrations (zigzagging seasonally due to the massive intake of CO2 by the northern hemisphere’s deciduous forests over the north’s summer months), try to imagine how that line could peak and begin to step downwardly. It can happen — with holistic education aimed at a widespread effort towards large-scale rehabilitation of our soils; be they deserts, savannahs, scrub lands, set-asides, farms and gardens. Rapid revegetation can put our CO2 rich skies back into balance — pulling the carbon down into our soils, where it becomes a source of fertility, and thus even more vegetation…. The cycle of stupidity, that is our current carbon cycle, can thus become a cycle of stability, health and prosperity.

And, in case you think it can’t be done, consider that we’ve actually cooled the earth before — and not that long ago. Take a look at what is now termed the ‘little ice age’, which ran approximately from 1350 to 1850AD. Over these centuries there were a few significant dips in average global temperatures, and there is a lot of evidence to show that these cooling periods were caused by rapid regional revegetation in Europe, Eurasia and the Americas. In this case the rapid revegetation was caused, not by the work of such educational institutes as our own, but rather because of a sudden die-off of human population numbers, due to disease.

Europe’s "Little Ice Age" may have been triggered by the 14th Century Black Death plague, according to a new study.

Pollen and leaf data support the idea that millions of trees sprang up on abandoned farmland, soaking up carbon dioxide from the atmosphere.

This would have had the effect of cooling the climate, a team from Utrecht University, Netherlands, says.

The Little Ice Age was a period of some 300 years when Europe experienced a dip in average temperatures. — BBC

CO2 oscillations of ~10 ppm in the last 1000 years are too large to be explained by external (solar-volcanic) forcing, but they can be explained by outbreaks of bubonic plague that caused historically documented farm abandonment in western Eurasia. Forest regrowth on abandoned farms sequestered enough carbon to account for the observed CO2 decreases. Plague-driven CO2 changes were also a significant causal factor in temperature changes during the Little Ice Age (1300–1900 AD). — The Anthropogenic Greenhouse Era Began Thousands of Years Ago (PDF), William F. Ruddiman, Department of Environmental Sciences, University of Virginia, Charlottesville, U.S.A., Abstract.

A correlation between the plague pandemics and the CO2 decreases is apparent, but what mechanism actually links the two? The deaths of tens of millions of people because of plague would slow the long-term rate of rise of carbon emissions, but the CO2 curve would then simply rise more slowly or level off. To cause CO2 values to decrease by 4 to 10 ppm, CO2 must be taken out of the atmosphere and then put back within intervals as short as a century or so.

Historical records provide a plausible mechanism. The mortality rates of 25 to 40% during the major plague pandemics caused widespread abandonment of farms and rural villages. Huge amounts of carbon could then be rapidly extracted from the atmosphere and sequestered in new forests growing on the abandoned farmland. Land-use modelers note that abandoned cropland and pasture reverts to full-forest carbon levels in 50 years or less (Houghton, 1999). Later, as people returned to the farms and cut back the newly grown forests, the temporarily sequestered carbon would have been restored to the atmosphere. — The Anthropogenic Greenhouse Era Began Thousands of Years Ago (PDF), William F. Ruddiman, Department of Environmental Sciences, University of Virginia, Charlottesville, U.S.A., p. 282

As Tony Lovell’s video graphically demonstrates at top, our atmosphere is really a small part of the ‘mass’ that makes up everything that constitutes our planet (see the graphic at 2:36 showing how much space our planet’s air would take up if at sea-level density). The massive destruction of forests, in combination with industrial soil management practices, has had a dramatic impact on our atmosphere’s carbon balance. The good news is that this trend can be reversed, simply by letting, and even helping, nature do what it naturally wants to do — grow! This is where permaculture is such a powerful mechanism, as it allows us to revegetate the earth, whilst also providing for our immediate, and future, needs.

The other alternative, of course, is just to wait until climate change has killed off most of us, and the rebounding vegetation will bring things back into balance…. I’d prefer to stick around a little longer myself, if I can help it….

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