Here is my op-ed published in the Detroit News on December 23.
Climategate: What e-mail really means
By now, most people are aware of the scandal surrounding the leak of thousands of e-mails and other documents from the University of East Anglia’s Climate Research Unit (CRU). Among these is an e-mail exchange involving several of the world’s leading climate scientists, dated October of 2009, in which the admission is made that even their best models cannot account for the last decade of temperature data. “The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t,” said Kevin Trenberth, one of the world’s preeminent climate scientists and lead author of the 2001 and 2007 IPCC reports.
Significantly for public policy, the admission implies that efforts to reduce carbon dioxide emissions — including the EPA’s endangerment finding, all forms of cap-and-trade-style legislation, and any possible resolution to emerge from the recently convened Copenhagen conference –have no basis in science .
Trenberth’s statement is compelling on its own, but the subsequent discussion is even more illuminating. Later in the same e-mail thread, fellow climate scientist Tom Wigley replies that he does not agree with Trenberth’s assertion. Trenberth then responds to Wigley, clarifying and expounding upon his earlier claims:
“How come you do not agree with a statement that says we are no where close to knowing where energy is going or whether clouds are changing to make the planet brighter. We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!”
This comment requires some scientific translation for its significance to be fully understood. The “energy budget” is the total energy gains and losses incurred by the Earth. The overwhelming majority of the energy entering the Earth comes from the Sun. Some of that energy is reflected back out into space by the atmosphere, clouds, and the Earth’s surface, while the remaining energy is absorbed, and is later reradiated as heat. The amount of energy the Earth gains is approximately equal to the amount it loses, which is why global temperatures remain relatively stable from day to day.
We have fairly good estimates of how much energy is entering the Earth, and we know from the laws of thermodynamics that energy cannot cease to exist, so “balancing the energy budget” simply entails accounting for where all that energy is going. “Global warming” refers to the condition in which the Earth as a system is taking on slightly more energy than it is losing for a sustained period, causing it to heat up over time. Therefore, it is highly significant when one of the world’s leading climate scientists asserts that we are “no where close to knowing where energy is going” and “not close to balancing the energy budget”.
In this context, “geoengineering” refers to any deliberate effort to affect net energy gains or losses to achieve a desired result, such as a cooler planet. The energy income of the planet is approximately static, and also well beyond our control, so affecting net energy flow necessarily involves changing systemic energy losses.
Greater atmospheric concentrations of greenhouse gases, like carbon dioxide (CO2), can reduce energy loss, so reducing CO2 emissions is one method of geoengineering. Indeed, Trenberth, in a letter published in the February 2009 issue of Physics Today defined “geoengineering” to include all efforts to “reduce emissions … or reduce the amount of carbon dioxide in the atmosphere.” Therefore, using his own definition of “geoengineering,” Trenberth’s remark could be interpreted thus:
The fact that we can not account for what is happening in the climate system makes any consideration to reduce emissions … or reduce the amount of carbon dioxide in the atmosphere quite hopeless as we will never be able to tell if it is successful or not!
All policy actions that would be required under the EPA endangerment finding, cap-and-trade legislation, and any global climate treaty amount to attempts to reduce carbon dioxide emissions. Thus, by his own admission, Kevin Trenberth appears convinced that all these efforts are quite hopeless indeed.
Daniel Compton is a research associate at the Competitive Enterprise Institute and contributor to OpenMarket.org