Are emission targets ever really ‘science-based’? Or are we playing a dangerous game of self-deception?

Last month, Senator Barbara Boxer proposed six principles for climate legislation, the first of which was:

1. Reduce emissions to levels guided by science to avoid dangerous global warming.

The National Call to Action on Global Warming, announced last week by a coalition of fifty environmental and public-interest groups, is more specific. Its first stated objective is the following:

Establish Science-Based Pollution Reduction Targets. Cut total, economy-wide global warming emissions by at least 25 percent below 1990 levels by 2020 and by at least 80 percent below 1990 levels by 2050 …

How were these targets established? The coalition’s announcement outlines the scientific basis in the introductory paragraphs:

To avoid the worst effects of global warming, there is broad scientific agreement that we must limit additional warming to no more than 2 degrees Celsius over pre-industrial levels. According to the IPCC, we have a reasonable chance of meeting this objective if developed countries as a whole cut their emissions by 25-40 percent below 1990 levels by 2020 and by 80-95 percent below 1990 levels by 2050; within this time frame, major developing countries also must act.

More recent findings since the publication of the latest IPCC assessment suggest that even more urgent action may be needed. …

Regarding the comment that “recent findings … suggest … may …,” the latest science is less equivocal:

Recent observations confirm that, given high rates of observed emissions, the worst-case IPCC scenario trajectories (or even worse) are being realised. For many key parameters, the climate system is already moving beyond the patterns of natural variability within which our society and economy have developed and thrived. These parameters include global mean surface temperature, sea-level rise, ocean and ice sheet dynamics, ocean acidification, and extreme climatic events. There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts.

Apparently, the coalition’s first objective is not “science-based,” in the sense of ensuring avoidance of catastrophic climate change, because it is based on the most minimal IPCC-based targets, which have been superseded by more recent findings. And whatever Senator Boxer and Congress do, they are not going to mandate science-based targets sufficient to “avoid dangerous global warming”—that threshold has evidently already been crossed.

The objective reality is that climate legislation is and always has been driven primarily by politics and cost-consciousness, and only secondarily by scientific realities. But does it do any harm to pretend that policies are “science-based”? Yes, it does.

The pretense lulls us into a self-deceptive sense of security, thinking that no effort or expense need be expended to surpass mandated caps or targets because their “scientific basis” ensures “environmental certainty.” For example, there is no perceived justification for a meaningful price floor to stabilize carbon trading prices, because low prices (e.g. the recent price collapse in the EU ETS, or the RGGI’s anemic $3/ton price) are an indication that environmental goals are being achieved at the lowest possible cost.

This perspective was articulated by EDF’s Tony Kreindler in seeking to rationalize EDF’s opposition to a price floor:

If we’re reducing emissions on schedule, if we’re achieving the environmental goal with the cap, why would we not want to do it at the lowest-possible cost?

The consequence of EDF’s “lowest-cost-at-any-cost” philosophy is evidenced by the U.S. SO2 trading system, which continues to focus regulatory incentives on further cost reductions, not further emission reductions, even when costs are far below initial expectations and when further investment in SO2 emission reduction would yield an estimated societal return-on-investment of 2500 percent. Under the cap-and-trade regulatory regime established by EDF such further reductions can only be sought through an Act of Congress (or through a very protracted court battle). And yet this very same regulatory model is being adopted on a global scale for GHG’s under the mythic notion that caps somehow ensure “environmental certainty”.

The practical consequences of our self deception are illustrated by California’s implementation plan for GHG regulation (AB 32). It is estimated, for example, that further reductions in passenger-vehicle CO2 emissions (beyond the state’s established Pavley regulations) could be achieved at an incremental cost of $149 per metric ton (MT), but would yield savings of $411/MT (from reduced fuel consumption), resulting in net savings of $262/MT. A couple of regulatory options that are under consideration might motivate such further reductions, but under the current AB 32 plan this would not result in any benefit to statewide emissions because the state’s planned cap-and-trade system would simply shift emission allowances from transportation to other sectors. The only benefit would be reduced CO2 trading prices below the currently-projected $10/MT. This minimalist approach of seeking only the minimum emission reductions sufficient to achieve the cap contravenes the AB 32 mandate requiring “the maximum technologically feasible and cost-effective greenhouse gas emission reductions …” But with the exception of Earthjustice, I am not aware that any of the 50 signatories to the National Call to Action on Global Warming have supported action to secure CARB’s compliance with the maximum-reduction requirement.

California’s maximum-reduction mandate, though not yet effected, represents a pragmatic alternative to fictionally “science-based” targets. Emission targets and caps can be employed to establish minimal regulatory requirements (as they are under AB 32)—which will invariably be based more on considerations of political acceptability than on science. But beyond that regulations should operate to motivate further emission reductions to the extent possible within defined limits of feasibility and cost effectiveness. The realities of science and politics require a best effort to reduce emissions—not the minimalist, least-effort approach currently advocated by EDF and California regulators.

[Revised 3/21/2009]