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The Evolving Real Greenhouse Warming Controversy
In the months preceding the December 1997 Kyoto Climate Conference, a remarkable shift occurred in the media focus on the greenhouse warming problem. A flurry of articles appeared in the major media that were specifically designed to inform the public about the science underlying greenhouse warming. Suddenly, the science had become newsworthy, and the obligation to educate the public had assumed a much higher priority.
What drove this major shift in media attention toward this long-standing issue? The obvious answer was the Kyoto Conference. This assemblage of representatives of essentially all the nations of the world was charged with beginning the virtually unthinkable- changing the way the world uses fossil fuels to produce its massive energy demands. Suddenly, people all over the planet were involved, and greenhouse warming was no longer a bit player. Quite literally, the Kyoto process itself was threatening to change everyone's personal world, in possibly large, threatening, and unpredictable ways.
The implications of the Kyoto process led to a flurry of major advertisements and infomercials designed to buttress and/ or defend particular points of view. Environmentally oriented persons and groups emphasized the threats that elevated levels of greenhouse gases might cause for life on earth, human and otherwise. Fossil fuel producers and users emphasized potential damage to the economy and to the specific industries that produce and directly use fossil fuels. Both positions were expressing valid concerns.
Fascinatingly, the media jumped back into the greenhouse warming problem at a level that substantially exceeded the level at which they had pursued the original controversies. The media now realized that there are thousands of stories in the upgraded greenhouse story, phase two.
One can understand this dramatic shift in media attention by performing a simple thought experiment. Imagine, by some miracle of scientific wizardry, that the science of greenhouse warming is now definitively complete, that climate scientists can state with amazing precision the ways climate would change under any variety of scenarios of future atmospheric concentrations of greenhouse gases and radiatively active airborne particulates. Would the greenhouse warming controversies go away? Hardly. Indeed, I argue that greenhouse controversies will actually escalate substantially, for a host of readily understandable reasons. Some of the reasons are outlined below.
To illustrate the first reason, assume that the "definitive" state of climate science is being used to evaluate the standard IPCC "toy" scenario of ramping up to a doubling of CO2 over preindustrial levels and holding it there indefinitely. Also assume that the midrange global-mean estimate for this problem ( ~3°C for doubled CO2 ) is actually the correct answer. What kinds of specific climate changes might we expect to see? According to Manabe & Stouffer (19) and IPCC (12), we would expect (a) land to warm more than oceans, (b) a substantial retreat of northern hemisphere sea ice, (c) sea level to rise more than a meter over the next several hundred years, (d) a sharp reduction in the overturning circulation of the North Atlantic ocean, and (e) substantial reductions in midcontinental summer soil moisture (~25%). Also, we would expect increases in the intensity of tropical hurricanes/ typhoons, at least for those that tend to reach mature stages (20). Sharp increases in summertime heat index (a measure of the effective temperature level a body feels on a humid day) would be likely in moist subtropical areas (21). The above list of changes, if realized, would place significant stresses on many aspects of life on earth. It is likely there would be many losers and some winners. The values and equity clashes resulting from this kind of a human-caused climate change scene are likely to be intense and long lasting.
For the second reason to expect amplified controversy, note that there remains an important possibility that the actual climate sensitivity could be near the lower limit of the generous ranges of the current best estimates ( ~1.5°C for doubled CO2 ). Even this lower level of climate sensitivity to added CO2 can become problematic, however. As pointed out in the 1994 IPCC Report on Radiative Forcing of Climate Change (18), our current fossil fuel- use social trajectory is pointing well toward a quadrupling of CO2 levels over their preindustrial values. At those high CO2 levels, even this lower level of warming response to CO2 increases, and its potential impacts become surprisingly "unsmall" (see the doubled CO2 effects for the midrange estimate above).
A third reason is that, near the current upper limits of climate sensitivity for the current societal CO2 trajectory, the large projected climate changes indicate that the potential impacts would likely become dauntingly large (19).
The above hypothetical cases point out that there almost inevitably will be a growing global requirement to move toward a change in the world's use of fossil fuels. That, of course, is what the Kyoto Conference was all about- to begin the process of nudging the world away from its current fossil fuel usage profile in the interest of preventing substantial climate change.
The Kyoto process was widely criticized for doing too much, for doing too little, or for being too lenient on the CO2 emissions being produced by the other guy (country, industry, generation...). Obviously, this "Who pays and how much and when?" debate is already the source of major controversy that is guaranteed to escalate as these "agreements" evolve toward real commitments by real countries, real industries, and real individuals. Now the real controversies begin. Nowvalues clashes become substantive, and ubiquitous. Most of us want to ensure that our particular set of wants and needs are not disproportionally impacted. Equity-driven values debates will inevitably be contentious and emotional. We thus are left with the conclusion that Kyoto's real purpose was to initiate the effort to nudge us down from our current social trajectory that is pointing toward quadrupled CO2 levels (18). The really hard decisions will have to be made in a future series of "Kyoto" conferences.
Beyond the Kyoto process, the controversies are almost guaranteed to escalate further. Underlying the Kyoto approach is what appears to me to be an implicit assumption: We can proceed reasonably on the policy side if we can all quietly assume, for now at least, that an eventual doubling of CO2 levels would lead to an acceptable level of climate change, but that higher CO2 levels would become progressively problematic. From the current scientific information base, what major entities have concluded that? Certainly not the IPCC 1995 assessment (12). The uncomfortable answer is that no major bodies have reached such a conclusion. So what is going on? I suspect that this implicit assumption is actually driven by the widely, but not unanimously, perceived enormous difficulty in capping the eventual CO2 at a doubling, let alone at lower levels. The Kyoto process seems to have quietly and wisely concluded that it needed to begin from some point that allows incremental actions to begin, even if they are small steps relative to the real problem.
Thus, the REAL greenhouse warming controversy is almost guaranteed to escalate further. In order for the Kyoto process to have had any rational hope of success, the other half of this effort had to be left off the table. Other half? Well, yes. The Kyoto debates were about who pays for the initial costs of reducing CO2 emissions. The part left undiscussed was the debate about who "pays" for the impacts caused by the unmitigated CO2 emissions. The tacit agreement to allow significant climate change (CO2 doubling or more) was "left home" in the Kyoto process. This highlights another fundamental values debate that will surely add daunting levels of complexity and emotion to the process. The equity issues are multidimensional: climate change winners versus losers; rich versus poor; environment versus economy; our generations versus future generations... In short, the values, equity, and impacts debates on the cost of realized climate change will inevitably be addressed in a substantially more focused way than is currently underway. The stakes and the emotional levels of the arguments will be very high. There will likely be clear winners and clear losers. It will take a long time, decades to a century, to sort all this out. This is because the costs of sufficiently aggressive mitigative action are likely to be very high, clearly so if net global CO2 emissions are to be sharply reduced. However, the "costs" of doing too little to prevent significant climate warming are also likely to be very high and would be levied for many centuries.
Simply put, this problem has no soft landing spot. This is the REAL greenhouse warming controversy. Think of it as our "present" to our great grandchildren.