Al Gore must have known going into the ECO:nomics summit in Santa Barbara today that there would be skeptics in attendance. After all, this event is put on by News Corp's Wall Street Journal, a publication historically critical of Gore's seemingly anti-free market call-to-arms. And the morning sessions featured Fox News darling Bjorn Lomborg, aka the "Skeptical Environmentalist" who launched a big career after publishing a controversial book by the same title in 2001 which denounced global warming.

Lomborg, a purported "liberal," has assembled economists to look at the return-on-investment of various humanitarian efforts — from funding education, to eliminating tuberculosis, to mitigating global warming. His results ... fighting climate change is not an "economically sound investment."

According to Lomborg, for every dollar spent fighting global warming through mechanisms like a carbon tax, 90 cents of value is provided. Whereas, every dollar spent on fighting TB yields $30 of value (accounting $1000 for every human-life-year). And every dollar spent on R&D for new energy would yield $11 of value.

So the anticipated sparks flew when Lomborg challenged Al Gore to a public debate saying, "I know you've dodged this bullet before."

Al Gore's response: "I don't want to be rude to you ... but these numbers have been debunked numerous times."  To paraphrase, he said it wouldn't be worth anyone's time to enter a debate in which hypothetical economic projections are pitted against solid, real facts. Gore cited recent submarine data in the Arctic which indicates that a total thaw of the arctic ice cap could take place during summer months in less than 5 years.

The multiple, compounded repercussions from such a cataclysmic event are just beginning to be understood and (though Lomborg claims they have been addressed in his calculations) it seems far-fetched that any environmental scientist, much less an ivory tower economist, would have a realistic sense of the true total impact of climate change over the next 100 years, given a scientific landscape that changes monthly.

A few examples Gore provided — 1 foot of sea level rise displaces 1 million people with current models showing 20 feet or more of sea rise. Then there is the big "methane monster" lurking beneath the permafrost in Greenland which could release in just a few short years a giant packet of greenhouse gases equal to the amount of all the CO2 released to date. Even subtle shifts in climate effect the breeding cycles of insects and birds (which eat the insects) leading to a shift in populations of malarial mosquitos and bacteria-toting ticks. And then there is the threat to pollinator insects like bees, without whom our entire food chain could well collapse.

But Gore did end on a positive note and in fact a place of agreement with his nemesis Lomborg. R&D is key. Al Gore believes that we do have the technology we need right now to be fossil-free by 2020. But it will take strong political will, something on the order of JFK's initiative to get a man on the moon, to get that technology to scale so that it has the positive impacts we desire.

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