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Robust Discussion of Rising Seas

KQED’s Forum program devoted a full hour this morning to recent projections for sea level rise and the threat it poses to California. Listen to the archived program here.

I joined host Michael Krasny and guests Peter Gleick and Will Travis, to discuss some of the recent findings. Travis heads the Bay Conservation & Development Commission and Gleick’s Pacific Institute issued a new report on the impacts last week.

Travis is just back from a trip to The Netherlands where he was studying some of the engineering techniques that the Dutch have deployed, to keep the North Sea at bay. Gleick has been tracking the issue here in California since 1990.

Gleick’s impact projections were underscored last week when scientists at a climate conference in Copenhagen projected a potential one-meter rise in the mean sea level by the end of this century, depending on how soon and how much we’re able to cut greenhouse gas emissions. That’s a pretty significant adjustment from the 2007 UN report, which had the rise pegged at a foot or two over the same time span. And two months ago, a USGS-led report postulated that a four-foot rise isn’t out of the question.

Some interesting questions and comments that came in from listeners:

– Sewage treatment plants in the Bay Area recently overwhelmed by storms are one glimpse into a future with higher sea levels.

– If pumps that convey water through the giant state and federal water projects in the Central Valley were solar-powered, it would reduce the carbon footprint of moving water around in California (often cited as 20% of our electricity use).

– A barrier at the Golden Gate could help “stem the tide” and potentially be part of a plant generating tidal power (Travis was skeptical).

– The Earth’s rotational bevavior also affects sea level and should be factored in.

In response to a listener who asked about a recent newspaper column that was dismissive of the prevailing climate science, I got the following note from Dave Johnson, a former Silicon Valley lawyer who teaches at Stanford:

“As to the climate-change contrarians, my short-form answer is this: I favor giving the scientifically-credible contrarian point of view some credit, and quite likely more than Al Gore or others would like. Why? Not because they necessarily have the science part right (or closer to right) than the IPCC.  Rather, it’s because the problem itself is a very complex system. Science is just now scoping the boundaries and behaviors of complex systems; to predict their behavior (especially of non-physical systems) will, to paraphrase Edward Witten, require ’22nd century’ knowledge.  As such, we all have to recognize the possibility, if not likelihood, that the global climate system might do things that we cannot fathom, much less predict. One possibility is self-correction to an equilibrium that can hold for another century or two. The other, sadly, is the converse – a spin-out into disequilibrium. Objectively, each has its percentage of possibility; so, objectively, each has to be seriously considered.  In short, whether I agree or disagree with the contrarians is, objectively, of no moment whatsoever.  In science, the strongest advocate of a particular conclusion must embrace the most aggressive testing of that conclusion. “

Hard to disagree with that. It’s always perilous to dismiss contrarian views out of hand. Galileo was a contrarian.

IPCC Scientist: A “Vicious Cycle” of Carbon Spikes

For a while now, we’ve been hearing that greenhouse gas emissions are still off the charts, which is to say increasing beyond the U.N.’s worst-case scenario for global warming. Now a Stanford researcher has laid out some specific scenarios–and they’re not pretty.

Chris Field, who is working on the next IPCC report, said “There is a real risk that human-caused climate change will accelerate the release of carbon dioxide from forest and tundra ecosystems, which have been storing a lot of carbon for thousands of years.”

Field, a professor of biology and of environmental Earth system science at Stanford, and a senior fellow at the Woods Institute for the Environment, issued a warning for members of the American Association for the Advancement of Science (AAAS) in Chicago today: “We don’t want to cross a critical threshold where this massive release of carbon starts to run on autopilot.”

And yet, that would appear to be path that we’re on. As Field told the AAAS symposium, “We now have data showing that from 2000 to 2007, greenhouse gas emissions increased far more rapidly than we expected, primarily because developing countries, like China and India, saw a huge upsurge in electric power generation, almost all of it based on coal.”

So what would some of the consequences be? “Tropical forests are essentially inflammable,” Field said. “You couldn’t get a fire to burn there if you tried. But if they dry out just a little bit, the result can be very large and destructive wildfires. It is increasingly clear that as you produce a warmer world, lots of forested areas that had been acting as carbon sinks could be converted to carbon sources. Essentially we could see a forest-carbon feedback that acts like a foot on the accelerator pedal for atmospheric CO2.”

The loss of functioning forests worldwide is already estimated to account for about 20% of carbon emissions. But field also warns of another carbon burst from decomposed plants that have been locked in permafrost for tens of thousands of years. As if all that weren’t plenty, Field says the accelerated forest destruction and melting permafrost could combine to create a “vicious cycle” of accelerated carbon emissions.

Field sums up by saying: “We now know that, without effective action, climate change is going to be larger and more difficult to deal with than we thought.”

The Chicago symposium is being held to address new developments since the last IPCC interim report, in 2007. A formal update is due out next year. Field is co-chair of the IPCC’s Working Group 2, which is assessing the impacts of climate change on social, economic and natural systems.

Life After Oil

3116043117_9bdc0bc414_m.jpgScientists at the American Geophysical Union conference made it clear on Wednesday that if peak oil isn’t here now, it’s coming very soon. The US reached its peak in 1971, and according to NASA scientist Warren Wiscombe, most estimates place the global oil production peak between 2000 and 2017. While surely problematic for industry, transportation, and agriculture, could peak oil actually be a good thing from a climate perspective? Burning less oil has got to be good for getting CO2 emissions down, right?

Well, that all depends on what we do.

Ken Caldeira of the Carnegie Institution for Science at Stanford says that oil is actually only a second tier concern when it comes to climate change because there’s not enough of it left to sustain CO2 levels at dangerous levels for very long. The real impacts will depend on how we replace oil as it disappears.

“Coal is the big bear on the block,” said Caldeira. “As we approach the end of oil, will we choose coal or will we choose low carbon technologies?”

Coal may be cheap and abundant, as the coal lobby would have us know, but replacing oil with coal-derived fuels would actually increase global CO2 emissions, according to Caldeira. Not only is coal a “dirtier” fuel than oil (coal emits more C02 per unit of energy than oil does), but there are also greenhouse gases emitted in the process of liquification.

Caldeira spoke on Wednesday at the AGU conference about his recent study examining what could happen to the climate if we ran out of oil today. He created two scenarios, one where we replace oil with coal, and one where we replace oil with renewables. Both scenarios assume we continue to use coal for the same purposes that we do today.  Under the oil-to-coal scenario, carbon emissions will actually increase, causing global temperatures to rise three years sooner than predicted under the Intergovernmetal Panel on Climate Change’s A2 scenario, increasing by 3.6 degrees F by 2042 instead of 2045. In his second scenario, where oil is replaced with renewables such as wind, solar, and nuclear, however, the same temperature rise would be delayed 11 years, to 2056.

“Addressing the climate problem means addressing the coal problem,” said Caldeira. “Most future climate change will be the result of burning coal in absence of policy.”