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March 6, 2012, 2:52 pm

Meet Jonathan Foley, ‘Climate Pragmatist’

By ANDREW C. REVKIN

Late in 2010, Jonathan Foley, who directs the Institute of the Environment at the University of Minnesota, wrote “Becoming a Climate Pragmatist,” an essay published online then and the following spring in the institute’s magazine, Momentum. You can get a feel for his work and views in the video above in which he explains 2009 research on “planetary boundaries.” I also encourage you to read his 2011 paper, “Solutions for a Cultivated Planet.”

I’ve mentioned his essay a couple of times but am overdue to draw direct attention to it, in part because as others have adopted or bashed the term “climate pragmatism,” Foley’s own views have largely been missed.

He is a scientist on the leading edge of climate change analysis  who proposes an end run around paralyzing climate disputes by focusing on energy and forest policies with multiple benefits and on fostering resilience to climate extremes. Yes, there is “selection bias” here, but I’m posting as a counterweight to the broader selection bias in climate discourse, which focuses on the loudest voices in the room. Here’s the core of Foley’s pitch:  Read more…

February 29, 2012, 6:06 pm

A Fresh Scientific Defense of the Merits of Moving from Coal to Shale Gas

By ANDREW C. REVKIN

There’s been a fresh development in a prolonged intellectual tussle among researchers at Cornell University over the climate benefits of moving from coal to natural gas, including gas extracted from shale using hydraulic fracturing, or fracking.

Lawrence M. Cathles of the Department of Earth and Atmospheric Sciences, with three colleagues, has offered a fresh rebuttal to the conclusions of a team led by Robert Howarth, a biogeochemist at the university.

Here’s the conclusion from Cathles et al. and a link to their long reply: Read more…

February 2, 2012, 11:41 am

Two Nobelists Offer Views of Human-Driven Global Warming

By ANDREW C. REVKIN

3:05 p.m. | Updated |
Given the flurry of attention this week around what two batches of scientists of various stripes think of evidence that humans are exerting a growing and disruptive influence on climate, it’s worth checking in with two Nobel laureates who’ve long been focused on the atmosphere and climate.

As I’ve written before, whatever your view of the science and policy choices related to global warming, you can probably find a Nobelist with matching views. But Mario Molina and Burton Richter deserve a prominent place at this table given their sustained attention to relevant issues.

Mario Molina, a Nobel laureate in chemistry, uses this image representing a partially completed jigsaw puzzle to convey the state of understanding of human-driven climate change.Mario MolinaMario Molina, a Nobel laureate in chemistry, uses this image representing a partially completed jigsaw puzzle to convey the state of understanding of human-driven climate change. CLICK TO ENLARGE

While participating in a November conference connected with the International Year of Chemistry, I spent time talking with Molina of the University of California, San Diego, a 1995 laureate in chemistry for his work (with others) on the atmospheric impact of ozone-destroying refrigerants and related chemicals. In a talk at the event, he conveyed his view of the incomplete, but compelling, picture of greenhouse-driven climate change with this photo illustration (right).

[3:05 p.m. | Updated | In a comment below, Laurie Dougherty helpfully pointed to 2010 congressional testimony by Molina in which he described his jigsaw analogy this way:

There appears to be a gross misunderstanding of the nature of climate change science among those that have attempted to discredit it. They convey the idea that the science in question behaves like a house of cards: if you remove just one of them, the whole structure falls apart. However, this is certainly not the way the science of complex systems has evolved. A much better analogy is a jigsaw puzzle: many pieces are missing, and some might even be in the wrong place, but there is little doubt that the overall image is clear, namely that climate change is a serious threat that needs to be urgently addressed. It is also clear that modest amounts of warming will have both positive and negative impacts, but above about 4 or 5 degrees Fahrenheit most impacts turn negative for many ecological systems, and for most nations. (Read the rest.)]

I’ve posted a lot on contrasting climate manifestos published in the past week by The Wall Street Journal, but it’s worth adding the perspective of Richter, a physics Nobelist who’s been deeply focused on humanity’s energy challenge, including the climate impact of greenhouse gases. As I’ve noted before, he’s the author of “Beyond Smoke and Mirrors,” a cogent road map for facing the daunting long-term challenge of cutting emissions of greenhouse gases even as humanity’s growth spurt crests in the next few decades.

Here’s a note Richter sent in reaction to the initial 16-author op-ed article in the Journal, which challenged the need for prompt action to stem emissions:
Read more…

January 8, 2012, 1:09 pm

The Next Ice Age and the Anthropocene

By ANDREW C. REVKIN
DESCRIPTIONAndrew C. Revkin In Greenland, a caribou skeleton lies before the snout of a glacier. Can humans prevent the ice sheets from advancing?

Jan. 9, 11:45 a.m. | Updated
If you’ve wondered where to look for signs that Earth is entering a geological epoch of our own making, the Anthropocene, what’s a good place to start?

I’d suggest the growing body of research concluding that what was once seen as an inevitable descent into the next ice age has been put off for a very long time by the building blanket of greenhouse gases generated by humanity’s burst of fossil fuel combustion.

A new addition to that literature — “Determining the natural length of the current interglacial” – is being published today in the online edition of Nature Geoscience.

The research, led by Chronis Tzedakis of University College, London, examined similarities between the current warm interval between ice ages and a particular point, around 780,000 years ago, during a past warm period known as Marine Isotope Stage 19. Using a variety of methods, the authors conclude that the onset of a new ice age would likely begin about 1,500 years from now, if the concentration of carbon dioxide was back below the levels produced since the Industrial Revolution.

I first explored when the next ice age would begin, and whether humans had forestalled that transition, in a Science Times article in 2003. James Hansen of NASA already had concluded at that time that the heat-trapping property of humanity’s gigaton-scale emissions of carbon dioxide was swamping the slight flux in incoming solar energy from periodic changes in Earth’s orientation relative to the Sun. ”We have taken over control of the mechanisms that determine the climate change,” he said.

In a news release one of the co-authors of the new study, James E.T. Channell of the University of Florida, echoes that point, saying: “The problem is that now we have added to the total amount of CO2 cycling through the system by burning fossil fuels. The cooling forces can’t keep up.” (Click here to read two news releases summarizing the work; a Popular Science post has more.)

I circulated the paper, under the journal’s embargo rules, to a variety of researchers focused on this question, including Hansen. Here’s the roundup of reactions: Read more…

January 6, 2012, 5:53 pm

On Shale Gas, Warming and Whiplash

By ANDREW C. REVKIN

Jan. 19, 4:00 p.m. | Updated below |
If you scan back you’ll see what’s becoming a pretty long series of headlines here dealing with a phenomenon I’ve noted since 2008 or so — a feeling of whiplash in tracking the flow of climate science and related news coverage. (One example is “On Plankton, Warming and Whiplash.”)

Here we go again. This time, the issue is the hydraulic fracturing of shale and similar rock to extract natural gas (and oil, as well). This technique, widely known as fracking, has raised environmental concerns while opening a vast new resource that is reshaping energy menus  from the United States to China.

Newly published research led by Cornell University scientists challenges the core calculations and conclusions of a paper by another Cornell researcher, Robert Howarth, that became a potent talking point for opponents of hydraulic fracturing last year. Here’s a link to the new paper, which was just published in Climatic Change.

The Howarth paper, “Methane and the greenhouse-gas footprint of natural gas from shale formations,” had estimated that leakage of gas from hydraulic fracturing operations (given that natural gas is mainly methane, a potent heat-trapping substance) and other factors made the climate impact of gas from such wells substantially worse than that of coal, measured per unit of energy. The abstract was bluntly worded: Read more…

January 4, 2012, 5:18 pm

‘Much Ado About Methane’

By ANDREW C. REVKIN

David Archer, the author of “The Long Thaw” and a Realclimate.org contributor, has weighed in at length on questions and assertions about the greenhouse risk posed by methane released from warming Arctic seabeds and tundra.

methane bubblesJosh Haner/The New York Times
In an Alaskan lake, bubbles of methane, a potent greenhouse gas, collect beneath the ice. More Photos 

I encourage you to have a look in relation to the string of recent posts here aiming to restore some scientific weight to an overheated debate that has even led one online community, the Arctic Methane Emergency Group, to call for urgent geoengineering countermeasures.

Here’s one excerpt and a link to the rest of the piece, which concludes, as many climate scientists do, that CO2, not CH4, remains the key target if the goal is limiting disruptive greenhouse warming: Read more…

December 28, 2011, 1:13 pm

More Views on Climate Risk and Arctic Methane

By ANDREW C. REVKIN

In trying to clarify what’s known, unknown and learnable about the possible contribution to global warming from vast methane deposits beneath Arctic seas, I reached out to a host of scientists working on this question. I also received a lot of reader input, as you can see from the comment threads in the string of posts on this important issue. Here’s a roundup of some additional views from the scientific community and one filmmaker focused on question:

Raymond T. Pierrehumbert, a climate scientist at the University of Chicago and contributor to Realclimate.org (and sometimes Dot Earth), sent this thought:

Regarding the methane time-bomb issue, I do understand the need to respond to unwarranted predictions of catastrophe. I’ve made responses of this type myself. For example I think that Jim Hansen is demonstrably wrong in his assertion that a Venus-type runaway greenhouse is a virtual certainty if we burn all the coal; he is right about almost everything and I greatly admire him, but he is wrong about this.

Countering an assertion like that has the unfortunate consequence that some people say, “Whew, ducked a bullet there,” and go on to think that the rest of the consequences of global warming don’t look so bad in comparison with turning into Venus, not remembering that a lot of those consequences can still be very bad indeed.

But the clathrate release problem is in a rather different category from the runaway greenhouse issue. It has to be seen as just one of the many fast or slow carbon catastrophes possibly awaiting us, in a system we are just groping to understand. The models of destabilization are largely based on variants of diffusive heat transport, but the state of understanding of slope avalanches and other more exotic release mechanisms is rather poor — and even if it turns out that rapid methane degassing isn’t in the cards, you still do have to worry about those several trillion metric tons of near-surface carbon and how secure they are. It’s like worrying about the state of security of Soviet nuclear warheads, but where you have no idea what kind of terrorists there might be out there and what their capabilities are — and on what time scales they operate.

Edward Brook, a climate scientist and geochemist at Oregon State University, sent a comment as part of a group e-mail exchange that included this relevant thought:

One problem with this discussion is that there is no definition of “time bomb” so people get confused. It seems quite likely that continued global warming will increase the emissions of methane from permafrost deposits and marine hydrates. Some of that will get in to the atmosphere, though … some will also be consumed in the water column and in soils. This “chronic” source may increase over time, and affect climate, but for the reasons you discussed it is likely to be slow, and not a catastrophic risk. Of course it is still important. For a somewhat dated view of this topic, see [link].

Gary Houser, an environmental writer and producer of a documentary that’s being made about Arctic methane, sent a rebuttal of my initial post in this string, “Methane Time Bomb in Arctic Seas – Apocalypse Not.” Here’s an introductory riff and link to his full piece:

As co-producer of an upcoming in-depth documentary on the methane issue, I am stunned at how Revkin has dismissed the concerns of those trying to alert the world to the danger of a methane runaway feedback. It is one of the scenarios most feared by climate scientists. Once triggered, an abrupt downward spiral could ensue which humanity might be helpless to stop. When the factors which could unleash a runaway are beginning to line up, it is a time for humanity to take a pause from its many distractions and look.

Revkin’s search for unequivocal “evidence” that such “runaway disruption” is already underway ignores the key danger we face. If humanity waits until this level of “proof” is obtained, it will very likely be far too late to stop the colossal forces that will already be in motion.

In my full counterpoint, I present seven major reasons why the situation is one of great urgency. They are listed below. I urge the reader to please consider my more complete statement.

1) A force that has already demonstrated its awesome power during earlier periods on Earth-
2) Grasping the meaning of “irreversible” runaway train-
3) Insistence on “evidence” trumped by need to act preventatively-
4) The factors present which could launch a “runaway”-
5) The creation of a collision course toward methane release-
6) A classic moment to invoke the precautionary principle-
7) An immediate need to escalate a scientific inquiry of methane-

Read the full piece here.

Richard B. Alley, the climate scientist and ice sheet prober at Pennsylvania State University (and host of the PBS series “Earth: The Operators’ Manual“), wrote this: Read more…

December 27, 2011, 12:54 pm

Leaders of Arctic Methane Project Clarify Climate Concerns

By ANDREW C. REVKIN

Dec. 29, 9:28 a.m. | Updated below |
I’ve been in touch with Natalia Shakhova and Igor Semiletov, the intrepid Russian researchers, based at the International Arctic Research Center in Fairbanks, Alaska, who for more than a decade have been leading an important international project analyzing methane plumes rising from the seabed in the shallow Arctic waters spreading north from eastern Siberian shores. (Here’s video of Shakhova describing the methane releases and their work.)

As I wrote recently, “Given that methane, molecule for molecule, has at least 20 times the heat-trapping properties of carbon dioxide, it’s important to get a handle on whether these are new releases, the first foretaste of some great outburst from thawing sea-bed stores of the gas, or simply a longstanding phenomenon newly observed.”

After their expedition this summer, Shakhova and Semiletov presented their latest observations at the American Geophysical Union fall meeting in San Francisco early this month, describing vastly larger methane releases in the mid-outer continental shelf than they had seen before in shallower water, leading to a fresh burst of headlines about risks of runaway warming.

Shakhova and Semiletov, whose earlier analysis of methane in the region was published in Science last year, had been unavailable for comment when I was preparing my piece, as they had gone on vacation shortly after their presentation. When they were back on the grid they got my e-mail inquiries and saw the post. Their response clarifies their differences with other research groups and emphasizes the importance of critically evaluating scientific findings before rushing to conclusions, either alarming or reassuring. One clear message, which I endorse, is the need to sustain the kind of fieldwork they’re doing.

Whether the issue is tracking Arctic methane or American stream flows, there’s a vital need for sustained, consistent observations, but — unfortunately — there’s a two-edged bias against such investments, given the appeal of focusing on science’s frontiers and the tendency to target monitoring programs — which are akin to bridge maintenance — when looking to cut budgets. That’s all fine until the bridge groans and buckles, of course.

Here is the contribution from Semiletov and Shakhova: Read more…

December 5, 2011, 4:10 pm

More on the ‘Sensitive’ Climate Question

By ANDREW C. REVKIN

Here are some fresh thoughts on the enduring and important questions surrounding  “climate sensitivity” – how much warming will result from a substantial buildup of greenhouse gases.

After my post on a much-discussed paper trying to clarify the extent of greenhouse-driven heating to expect in coming decades, I sought input from the lead author, Andreas Schmittner of Oregon State University. (As I mentioned, another author, Nathan Urban of Princeton University, provided one valuable view in a long interview posted on the Planet 3.0 blog.)

Here’s Schmittner’s reaction, focused less on specific technical criticisms and more on overarching insights and issues raised by his work. The research drew lessons from paleoclimate studies of the Last Glacial Maximum, the cold peak of the last ice age, that relate to the extent of warmth possible in an era of accumulating greenhouse gases: Read more…

November 29, 2011, 10:25 am

Straight Talk on Climate Progress in California and Beyond

By ANDREW C. REVKIN

Dec. 7, 1:11 a.m. | Updated below |
With the latest round of contentious international climate treaty negotiations getting under way in Durban, South Africa, it’s worth revisiting what would be required to meet ambitious targets set for greenhouse gases in California, a state that already has pledged meaningful action.

There’s a new peer-reviewed study of California’s plans, published in the current issue of Science, that largely echoes points made in a study by the California Council on Science and Technology issued earlier this year showing the scope of what would have to happen and the limits of known technologies.

Some details on the new study are below. But first it’s worth checking in on realistic paths to climate progress with a reliable guide — Nate Lewis, the head of the federal energy innovation hub on fuels from sunlight and a chemist at the California Institute of Technology.

Lewis is not only involved with cutting-edge research on next-generation technology, but has contributed to various assessments of options for achieving targets in that state and the nation, including the California Council study.

A few weeks ago, we had a long Skype chat about California’s much discussed plan to cut its emissions of greenhouse gases 80 percent below 1990 levels by 2050.

His conclusion, which I see as robustly supported by peer-reviewed work (including the new paper), is that California could get roughly halfway to that goal in a perfect world – one without impediments such as higher costs, nimby fights and resistance from consumers and industries wedded to fossil fuels.

But even in that perfect world, Lewis says, citing the reviewed literature, fundamental leaps in basic energy sciences would be required to get all the way – and the nation and world are not investing at anywhere the level that would be required in the related sciences and in development and demonstration of promising technologies.

Looking beyond California to the nation, Lewis cited a National Academy of Sciences report he co-authored with 40 experts in energy technology on a path to getting more than half of the country’s electricity from renewable sources by mid-century:

Everybody agreed that if we were going to get more than half of our electricity in our country from renewables by 2050 we were going to have to do things that we simply don’t know how to do today at all and fundamentally change the way we use, generate and consume energy [relevant section here]. That’s completely in agreement with the California report. And it’s different than people who would tell you that we have all the technology we need and we just need the political will and let’s be done with it. That’s not what any technically knowledgeable panel concludes.

Here’s a bit more from Lewis on this point, with more below:

Read more…