[Update: The answer, and its significance, can be found in the next post!]
To illustrate how much and how little in the climate debate, I reproduce for your reading pleasure the following excerpt from an essay by a very prominent scientist, made sometime in the past. Do you agree or disagree? Is it still relevant advice?
I'll provide an update soon with who said it and when. Enjoy!
For the first time in the decades that we scientists have been concerned about global environmental issues, political leaders seem ready to take concrete steps. They are looking to the scientific community for advice.
We are crossing the threshold from experimentalists, observational scientists, theoreticians, and modelers to the realm of advisors, guiding wise policy making. What advice would I give if I were preparing to brief a president or prime minister, about to make decisions, or about to go to a summit meeting, perhaps the first environmental summit meeting? Many of us in many nations will have to do something like this – for a head of state, a minister, or a parliamentary committee. Such policy makers will probably say, “Don’t give me a scholarly lecture, tell me what to do.” I will address myself to a fictional prime minister. All of the observations that follow have been made before by prominent scientists in our field.
Briefing to the Prime Minister
Prime Minister, human-caused global environmental problems are now high on the public agenda, and you must formulate a position. It is your job as a political leader to manage these risks, taking into account such matters as costs and politics, and it is my job as a scientist to assess these risks for you. I recognize that this boundary between risk management and risk assessment is a fuzzy one. . .
Greenhouse Effect
Prime Minister, the sources of greenhouse gases are well known: CFCs, deforestation, carbon dioxide from fossil fuel combustion, and methane from increased biological activity of humankind. There is little doubt among scientists that global mean temperatures will increase. The latest computer models predict a global average increase of up to 5 degrees C, with rises of up to 12” in polar regions. This temperature change is comparable to the warming since the last Ice Age. Of great concern, and great uncertainty, are regional effects on weather, such as storms, and particularly changing rainfall patterns. Sea level is likely to rise by one meter beyong 2050. Our understanding of this problem-the multiple factors and positive feedback possibilities-is poor. The models are too simple, and it may be at least a decade or two decades before we can do better. There is also a small but worrisome possibility of unwelcome surprises in this highly nonlinear system, i.e., disastrous excursions in climate triggered by small perturbations caused by human activity that could cause serious dislocations over the world.
Prime Minister, humankind’s intervention with climate is unprecedented; it is an example of one of the most difficult policy issues – great uncertainty and a spectrum of outcomes ranging from moderate to profound consequences. There are limited options open to you and other leaders to reverse this trend. CFC reduction and reforestation will have only a modest effect, but they are important for other reasons as well. Substantial reduction of CO2, which is responsible for half of the temperature rise, will require a change in the energy economy of the world at a cost of hundreds of billions to trillions of dollars and may not be technically possible over the next 40 years. I cannot recommend such large investments at this time in view of the uncertainties, but this does not mean doing nothing. I do urge you to undertake the following program as affordable minimum insurance against the possibility of worst-case outcomes:
(1) Support a fast-track initiative to improve the science of climatic change, including studying historic natural changes, improving data acquisition, and enhancing understanding of the atmosphere-ocean system by conducting global experiments, improving modeling (with bigger and more computers), and attracting more scientists to the field.
(2) Undertake initiatives that have merit independent of climatic change, such as improving energy security.
Some examples:
• A major push to reduce CO2 emissions by energy conservation;
• Improved water conservation in agriculture and industry;
• R&D initiatives in support of nonpolluting, safe alternate energy sources, tilting toward them when feasiable;
• Biotech initiatives to genetically engineer food plants to use less water and fewer chemicals;
• A survey of the nation’s water resources and water use policies, and preparation of preliminary plans for hydrological initiatives;
• Coastal zone management incorporating an anticipation of sea-level rise;
• Reforestation driven by the dual needs to preserve species diversity and to reduce atmospheric CO2;
• CFC cutoff and replacement by safe alternatives.
The cost of all these steps is a few billion dollars a year, manageable, and justifiable as prudent. As we reduce uncertainties in the years ahead, we will have to adjust out policies accordingly. . .
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