Philadelphia, April 15: Dr. Wallace Broecker, the 2008 Benjamin Franklin Medalist in Earth and Environmental Sciences, participated in a panel discussion at the Franklin Institute this evening on the Ocean and Earth's Climate. Moderated by NPR's Joe Palca, and joined by Dr's John Byrne (Center for Energy and Environmental Policy at the University of Delaware), D. James Baker (Global Carbon Measurement Program, The William Clinton Foundation), and Nancy Targett (College of Marine and Earth Studies, University of Delaware), Broecker announced that "our chances of preventing a doubling of CO2 since 1850, to 550 parts per million (ppm), is almost zero".
Broecker's latest book (coauthored by Robert Kunzig), Fixing Climate: What Past Climate Changes Reveal About the Current Threat - and How to Counter It, was officially released at the event and it's contents figured prominently in the discussion. Broecker said, "a leveling off atmospheric CO2 at between 550 and 650 ppm is within our power." That less than optimistic figure would guarantee a certain amount of serious consequences such as drying the northern latitudes and forcing more moisture into the tropics, and an significant but hard to estimate melting of polar ice with sea levels rising above the UN Intergovernmental Panel on Climate Change (IPCC) highest estimates.
In Fixing Climate, the chapter "Ice Melts, Sea Level Rises" , quotes John Mercer of the University of Ohio, and a long time observer of the West Antarctic Ice Sheet, who said in a 1978 article in Nature, "I contend that a major disaster - a rapid 5 m[eter] rise in sea level, caused by deglaciation of West Antarctica - may be immanent or in progress after atmospheric CO2 content has only doubled. This concentration of CO2 will be reached within about 50 years [2028] if fossil fuel continues to be consumed at its recent accelerating rate." The current rate of melting "unnerved" climate scientists after reviewing last years record ice loss in the Arctic at a conference in Fairbanks, Alaska. The loss of sea ice has forced a redrawing of maps of the Canadian north.
Broecker placed his hopes on a relatively new breakthrough on scrubbing CO2 out of the atmosphere that has been shown to work in small-scale pilot trials near Tucson, Arizona. Klaus Lackner, recruited to the Columbia faculty by Broecker from Los Alamos while working together at Biosphere 2, proposed scrubbing the CO2 from the atmosphere on a grand scale. The technique was not revolutionary and had been perfected for use in submarines, the space shuttle, and "a variety of industrial settings". "What was novel about Lackner's idea was the scale" "- and also his way of conceptualizing the task to show it was doable."
The project would not come cheap. Broecker estimated that it could take $600 billion a year to reduce the global concentrations by as much as a half over time. Of course, the estimates of what a failure to act would cost come in at much higher, according to the Nicolas Stern report, perhaps as much as an astronomical 20% of global GDP.
With CO2 rising at a rate of 2 ppm a year it will only take 35 years to eclipse all known CO2 records. "We're changing things on a decade time scale", said Broecker, "if we get to 900 ppm we'll change the entire ecology of the planet." The panel agreed that we'll have to employ every technique that we now have to forestall a catastrophe.
A carbon trading scheme and a massive reforestation of the planet would be essential parts of the solution. Dr. Targett decried the tendency for people to seek a quick fix. "We're looking for a silver bullet that doesn't exist", she said. The panel agreed that the fastest, cheapest first steps would be a program of energy efficiency and conservation, but that alone would not be nearly enough to stem the rising seas. For that, they said, we should be prepared to retreat from low-lying coastal areas. Unfortunately, although officials in coastal towns are willing to begin the process, said panel members, they're hampered by a lack of a clear understanding of where the rising tide lines would be.
After the panel had been answering questions from the audience that frequently centered on the resistance of governments to act, Broecker erupted angrily, "We have the ability to do it and we damn well better do it!" The question returned to how our ancestors might look back on us. So far, the consensus was that the evidence to date is that we won't be seen in any favorable light.
The issue of complicating factors from global energy demand outstripping available supplies and the potential of peak oil issues to interfere with international cooperation on dealing with atmospheric carbon and other greenhouse gas loading was acknowledged, especially by Dr. Byrne. There didn't seem to be any answer from the panel about how to cope with that.
The best hope, the panel hinted, would be for a radical shift in policy from a new administration after the November elections. They concluded that, at present, it couldn't get much worse.
