Wednesday, July 24, 2013

Saving the Earth from Climatic Disruption

Saving the Earth from Climatic Destruction

George M. Woodwell* and Richard A. Houghton**

The annual tax on GDP around the world from the climatic disruption has now reached well into the hundreds of billions of dollars and tens of thousands of early deaths. While economists have hardly led the world in acknowledging the emergency and in deflecting it, their recent annual field day in Davos produced some lucid and welcome insights. They had a World Bank report and a new World Bank president calling for immediate action.[1]  Christine Lagarde of the IMF was unequivocal in her response to a question:  “Unless we take action on climate change, future generations will be roasted, toasted, fried and grilled.”[2]   The question is what to do.

The popular discussion seems to revolve around accepting a two-degree C rise in the global temperature as tolerable and controllable. The suggestion is that the two-degree goal has been blessed as safe by a consensus of science. It is not a consensus of scientists nor is it correct that a rise to two degrees would be benign. The two-degree threshold was emphasized in the negotiations during the 15th Conference of the Parties to the Framework Convention on Climate Change in Copenhagen in December 2009.  It was an economic and political compromise that appeared to offer some room to establish effective action in reducing emissions globally. It does not have a scientific consensus behind it. It is, unfortunately, an attractive trap in that the current atmospheric burden exceeds the 1992 agreement under the Framework Convention to prevent dangerous interference with the climate system.
The warming to date has been about 0.8 degree C and the effects are conspicuous. The glacial melting in particular is moving more rapidly than most scientists had anticipated and considerably more rapidly than assumed by the Intergovernmental Panel on Climate Change.[3]  A thoroughly detailed report by the US Geological Survey compiled over years and dealing with the world’s glaciers observes that “… since the late 19th century, all of Iceland’s glaciers have decreased in area and thickness…. Since 1995…the decrease has been quite dramatic…. [They] will virtually disappear by 2200.”[4]   The Greenland and West Antarctic ice caps are also melting much more rapidly than earlier predictions. They contain in total as much as forty feet of sea level rise.[5]  A continuation of the accelerating rise in temperature will melt all the glacial ice and raise sea level by 75 meters, more than 225 feet.

The big issue that forecloses limiting an increase in mean global temperature to 2 degrees C, or even the present 0.8 degree, is the warming itself, most threatening in the Arctic.  It is a double threat in that the warming is greater in the higher latitudes than elsewhere and the Arctic contains a massive quantity of carbon potentially vulnerable to release as carbon dioxide and methane. The largest carbon pool is in the soils and peat of the tundra. There is also a significant pool in the soils and vegetation of the boreal forest. Both are circumpolar. Much of the peat in these landscapes is several too many feet deep. Some of it, containing an estimated 1700 billion tons of carbon,[6] twice the current amount in the atmosphere, has been frozen in permafrost for thousands of years.  Thawed, the carbon in peat and mineral soils is vulnerable to decay with the release of both carbon dioxide and methane.  Substantial quantities of methane have accumulated through slow decay over thousands of years in frozen soils and are released as the thawing proceeds.[7] Some is in crystalline form in shallow coastal waters that are also vulnerable to the warming. The total quantities of carbon dioxide and methane available from these sources are uncertain. They are, however, large enough to affect the current atmospheric burden and to be a major factor in the array of positive feedbacks associated with the warming.[8] 

While the Earth has warmed by less than 1 degree C, the Arctic has warmed by 2-3 degrees, more in some places, and the process of thawing long frozen soils is underway. The thawing of soils is a significant immediate source of methane. If organic decay is also stimulated, it has the potential for flooding the Earth with carbon dioxide far beyond any capacity we have for controlling it by reducing human emissions. 

The alternative is an overt, immediate, effort to stop the warming and ultimately to re-freeze the Arctic.  The first step is a rapid stabilization of the concentration of carbon dioxide in the atmosphere as agreed to by all the nations in 1992 when they signed and ultimately ratified the Framework Convention on Climate Change.  The action now requires reductions in human emissions from deforestation and combustion of fossil fuels.  Ultimately, a reduction in the heat-trapping gas content of the atmosphere will require abandonment of fossil fuels and a major effort at reforestation of the earth to sequester as much carbon as possible over the next decades.

It may not be possible. The Arctic release may not be controllable at this late date.  There is no alternative to attempting to check the process by cooling the earth now with the most powerful and safe methods.

The following are the facts. The total current releases from human activities are more than 10 billion tons of carbon from burning fossil fuels and from deforestation and degradation of, largely, tropical forests. The deforestation is contributing more than one billion tons of carbon. Burning fossil fuels is the rest, about 9.5 billion tons in 2011.[9]

Of those ten billion tons between 4 and 5 billion tons accumulate in the atmosphere. This accumulation is the immediate problem. It is rising. In the past year it was more than 5 billion tons, the second highest ever.[10]  The remainder of the 10 billion ton release is absorbed into the oceans and into terrestrial vegetation, largely forests. Those marine and terrestrial “sinks” amount currently to about 5 billion tons of carbon annually.  They are vulnerable, of course. Forests are vulnerable to disease and fire and drought as temperatures rise. The oceans absorb less carbon dioxide as the surface waters warm and become more acidic. And yet, we can, at this moment take advantage of the present circumstance to, first, stabilize the atmospheric composition, and, ultimately, to reverse the trends in climate.

There is no escape from reducing the use of fossil fuels. On the other hand, management of land and forests to conserve carbon is essential and will be significant. The first step is to stop further degradation and destruction of primary forests globally.[11]  That single step would remove more than 1 billion tons of carbon from the current emissions and from the annual accumulation.  Second, natural forests can be restored to deforested lands in the normally naturally forested zones.  A newly forested area of 2-4 million square kilometers stores, conservatively, about a billion tons of carbon annually during the phase of maximum growth of trees. Such an area or more can be found globally. Those two steps, desirable in any analysis of beneficial land management policies, would account for more than 2 billion tons of carbon annually from the 5 billion tons in excess currently. Thirdly, in an emergency, harvesting of secondary forests globally could be curtailed to avoid carbon releases during a transition period to ease pressures on use of fossil fuels. The combined effects would absorb and store in plants and soil 3-5 billion tons of carbon, annually, a major increment in starting the return toward the 300 ppm of the atmosphere at the beginning of the 20th century. Simultaneously, reductions in use of fossil fuels are essential, beginning at once.

Those steps would constitute a totally appropriate recognition of the urgency of stabilizing the biosphere, opening a new era in the industrial age with new industries with local foci, new jobs and new economic opportunities globally. There is no question that the human enterprise can be operated successfully and beneficially on renewable energy.  Within the last five years the cost of wind and direct solar energy has dropped to make it attractive in many circumstances on the basis of price alone. The transition must be now and rapidly advanced to deflect the drain on national GDPs from climatic disruptions now underway.  Uncorrected, environmental chaos will consume the last vestiges of global GDP and the world will be redefined by cascading environmental, economic and political catastrophes.[12]  

Notes and References

[1] J.Y. Kim, president of the World Bank, offered a strong statement based on the report:

[3] Intergovernmental Panel on Climate Change. Climate Change 2007: Impacts, Adaptation and Vulnerability. Cambridge University Press, Cambridge, UK.   Rahmstorf, S., Foster, G., Cazenave, A. 2012. Comparing climate projections to observations up to 2011. Environmental Research Letters 7:044035. doi:10.1088/1748-9326/7/4/044035

[4] Williams, R.S., J.G. Ferrigno, B.H. Raup., J.S. Kargel. 2012. Glaciers: The Earth’s Dynamic Cryosphere and the Earth System. U.S. Geological Survey Professional Paper 1386-A. Washington, DC.

[5] USGS. 2012. State of the Earth’s Cryosphere at the Beginning of the 21sr Century: Glaciers, Global Snow Cover, Floating Ice, and Permafrost and Periglacial Environments. U.S. Geological Survey Professional Paper 1386-A. Washington, DC. A 461.

[6] Hugelius, G., Tarnocai, C., Broll, G., Canadell, J. G., Kuhry, P., and Swanson, D. K. 2013. The Northern Circumpolar Soil Carbon Database: spatially distributed datasets of soil coverage and soil carbon storage in the northern permafrost regions. Earth System Science Data. 5:3-13, doi:10.5194/essd-5-3-2013

[7] Anthony, K.W., P. Anthony, G. Grosse, J. Chanton. 2012. Geologic methane seeps along boundaries of Arctic permafrost thaw and melting glaciers. Nature Geoscience 5:419-426. doi:10.1038/ngeo1480

[8] Woodwell, G.M., F.T. Mackenzie, R.A. Houghton, M.J. Apps, E. Gorham, E.A. Davidson. 1995. Will the Warming Speed the Warming? in  G.M. Woodwell and F.T. Mackenzie (Eds). 1995. Biotic Feedbacks in the Global Climatic System. Oxford University Press, New York. p 406.

[9] Le Quéré et al. 2012. The global carbon budget 1959-2011. Earth System Science Data Discussions 5:1107-1157.

[10] Feb. 2013.

[11] The World Commission on Forests examined that question extensively and found that at that time (the late 1990s) there would be no serious influence on the availability of timber or fiber globally. 1999.  Our Forests Our Future: Report of the World Commission on Forests and Sustainable Development.  Cambridge University Press, Cambridge, UK. While growth in all aspects of the global economy may have changed that conclusion, the need for action on climate has become acute.

[12] Oreskes, N., and E.M. Conway. 2013. The Collapse of Western Civilization: A View from the Future. Daedalus. Winter. p 40.  See also Ehrlich, P R., and A.H. Ehrlich. 2013. Can a Collapse of Global Civilization be Avoided? Proceedings of the Royal Society B 280(1754):20122845.

*G. M. Woodwell is Director Emeritus of the Woods Hole Research Center and currently Distinguished Scientist, Natural Resources Defense Council, 40 West 20th St., New York, NY 10011.

**Richard A. Houghton is Senior Scientist, Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540.