Update (pm November 10 2010): To make sure my post is clear, this post comments on just two parts of an otherwise excellent overview of the issues associated with geoengineering. The article is very informative in overviewing the approaches and the issues of geoengineering. My last paragraph should not have been specifically critical of the Economist, as the article does effectively discuss the concerns with geoengineering. It is other media that has generally not properly reported on this subject. I have edited the last paragraph of my post to clarify.
There is an informative summary of geoengineering in an Economist article in their November 6 2010 article titled (subscription required)
The article does provide a useful summary of a number of geoengineering proposals. However, it also perpetuates myths about climate science. The article includes the text that there is a
“subtle distinction between “global warming” and “climate change”.”
The article itself is inconsistent. In the same paragraph they write
“Double the amount of carbon dioxide in the atmosphere and the average global temperature will go up. Add the right amount of stratospheric sulphur and the temperature will come back down to where it began. There will, in other words, be no net global warming. But though the average temperature is unchanged, the climate is not.”
In the real climate system, global warming and cooling is just one subset of a much broader range of climate issues. There is no “subtle distinction”.
This was discussed, for example, in my post
In that post, I wrote
“Global warming is defined by a positive accumulation of heat (Joules) in the climate system, of which most occurs in the oceans (see Pielke Sr., R.A., 2003: Heat storage within the Earth system. Bull. Amer. Meteor. Soc., 84, 331-335). While surface temperature as also been used to define this heating, it has a range of problems with its use in this context, as we have discussed in our papers, and in earlier weblogs, with more to follow.
Human-caused climate change, however, involves forcings beyond the radiative forcing of the well-mixed greenhouse gases. As summarized in the 2005 NRC report, this includes the multiple influences of aerosols and of biogeochemically active gases, and land-cover changes. The regional changes from these forcings must be considered, even if there were no global warming from these forcings.
By conflating the terms “global warming” and “climate change”, we misinform policymakers, by leading them to believe that the radiative effect of the well-mixed greenhouse gases is the only major forcing of human-caused climate change. It is not. Dealing with climate change is a much more difficult issue than is captured by focusing on global warming.”
In Chapter 1 of my son’s book, The Climate Fix, this broader viewpoint is discussed in his section “Carbon dioxide is Important, but Climate Change Involves Much More”.
They also write with respect to geoengineering that it
“might have political ramifications—even though both countries come closer to their original climates with the other’s optimal level of geoengineering than with no geoengineering at all.”
The use of the term “original climate” perpetuates the misconception that the climate has some constant level in the absence of human intervention. This is an erroneous view as we demonstrate in our paper
Rial, J., R.A. Pielke Sr., M. Beniston, M. Claussen, J. Canadell, P. Cox, H. Held, N. de Noblet-Ducoudre, R. Prinn, J. Reynolds, and J.D. Salas, 2004: Nonlinearities, feedbacks and critical thresholds within the Earth’s climate system. Climatic Change, 65, 11-38
where we conclude that
“The Earth’s climate system is highly nonlinear: inputs and outputs are not proportional, change is often episodic and abrupt, rather than slow and gradual, and multiple equilibria are the norm.”
Until the broader media (and the policymakers) recognize the real complexity of the climate system, and the unknown risks of geoengineering, such articles
such as presented in the Economist will mislead with respect to the dangers of deliberate large scale intervention into the climate system. We already have a number of inadvertant human interventions (e.g. landscape change, aerosol emissions, CO2, etc) whose effects we still do not adequately understand.