February 18, 2010
Permafrost Line Moves North In Canada
In an area around the southern end of Hudson Bay in Canada the permafrost line has moved 130 kilometers (80 miles) northward in the last 50 years.
Quebec City, February 17, 2010–The southern limit of permanently frozen ground, or permafrost, is now 130 kilometers further north than it was 50 years ago in the James Bay region, according to two researchers from the Department of Biology at Université Laval. In a recent issue of the scientific journal Permafrost and Periglacial Processes, Serge Payette and Simon Thibault suggest that, if the trend continues, permafrost in the region will completely disappear in the near future.
The researchers measured the retreat of the permafrost border by observing hummocks known as "palsas," which form naturally over ice contained in the soil of northern peat bogs. Conditions in these mounds are conducive to the development of distinct vegetation—lichen, shrubs, and black spruce—that make them easy to spot in the field.
I would be curious to know how much methane is being released in the area that ceased to have permafrost. The resumption in the rise of atmospheric methane is cause for concern.. A potential source of positive feedback in warming comes from release of methane from previously permafrost ground since methane is a much more potent greenhouse gas than carbon dioxide. So far arctic methane does not amount to much of total global methane emissions:
They found that just over half of all methane emissions came from the tropics, with some 20m tonnes released from the Amazon river basin each year, and 26m tonnes from the Congo basin. Rice paddy fields across China and south and south-east Asia produced just under one-third of global methane, some 33m tonnes. Just 2% of global methane comes from Arctic latitudes, the study found, though the region showed the largest increases. The 31% rise in methane emissions there from 2003-07 was enough to help lift the global average increase to 7%.
CO2 is to CH4 and CH4 is to N2O
A few percent of nitrogen fertilizer ends up as N2O which is nearly 300 times as potent as CO2. "denitrification" in a world demanding more protein is an enemy, not simply of agricultural energy efficiency, but of global climate stability. Getting more of the fixed nitrogen into the form of consumable protein should be a high priority for agricultural research.
First, this is a lagging indicator.
Second, based on a lagging indicator, this sort of straight-line extrapolation is nonsensical: "if the trend continues, permafrost in the region will completely disappear in the near future." Well, sure. If any bad trend continues indefinitely then things will get worse.
The trick is moving beyond observation to prediction. Any thoughts on that or is a scary methane scenario based on an observation and possibly unrelated mechanism the best we can do?
"In a recent issue of the scientific journal Permafrost and Periglacial Processes, Serge Payette and Simon Thibault suggest that, if the trend continues, permafrost in the region will completely disappear in the near future."
Thats the best news I have heard all week! Hopefully trees and large plants will be able to move into this area.
I think scientists are pretty certain that thawing places will emit a lot of methane. Not sure how accurately they can forecast the amount of methane that will be released by warming of arctic land. Their view of methane as a greenhouse gas more certainly true since measuring absorption spectra of various gases has been done.
N2O emissions from agriculture do not get the attention they deserve. That's in part because arguing against population growth or industrialization is deeply unpopular. Where coal CO2 emissions seem avoidable if we'd only be willing to pay a few more pennies per kwh it seems far harder to cut N2O emissions.
Randall Parker: My point was that simply extending a straight line from one or two data points is not science and any predictions on that basis are pie-in-the-sky. I also sense a great deal of hedging in your comments, which given the fact that there's little data, is fair. "A potential source of positive feedback," "scientists are pretty certain," "will emit a lot of methane" - potential?, pretty certain?, a lot? Well, sure. I can agree that the potential exists. And I love scientific certainty, but I prefer data that can be examined to feelings of certainty, theories that can be tested, etc. And how much is "a lot?" I guess the question is this: is "a lot" "enough?" How do you know? Methane is certainly a potent greenhouse gas, but so it water vapor. Will warming tundra also emit more water vapor? More than it will emit methane? I suspect so, and I could construct an equally dire scenario based on that.
Looks like yet another study from the jacques pierre woodstock institute of unfounded intentional hysteria
from another study done in manitoba from the late sixties... "At one time, 60% of the land portion of the study area contained permafrost; at present the proportion is down to about 15% of the land area."
I hedge on climate science mostly because it is an area I've only recently started reading heavily on.
What I do not hedge on: CO2, CH4 (methane), N20, and black soot create warm forcings - and substantial ones at that. These gases are rising in the atmosphere and therefore their warm forcings are increasing. What I'm less sure of: How big of positive feedbacks do they generate? Certainly they create positive feedbacks. But how big are they? Near as I can tell the biggest unknowns in climate science appear to be about feedback loops.
Theories that can be tested: That's the problem with the planet's climate. We have only one planet and lack suitable controls for experiments. Modeling has to play a big role in developing predictions. So does paleoclimate data.
If the correlations in the paleoclimate data between CO2 and temperature mostly are due to CO2 forcings and positive feedbacks from those forcings then we are in trouble. So far in my reading I haven't come across plausible alternative explanations for the paleoclimate correlations. Still reading.
Randall Parker: I concur with nearly all. The only point I would add touches on your point re correlations. I would be interested in hearing in the future about any studies you encounter that address the point I've seen made that changes in temperature lead corresponding changes in atmospheric concentrations of C02. That would seem to bring into question the generally accepted causal relationship.
LAG: I am reading NASA Goddard Institute director and climate scientist James Hansen's Storms of My Grandchildren: The Truth About the Coming Climate Catastrophe and Our Last Chance to Save Humanity. Hansen says the initial changes in forcings that cause the Earth to exit or enter an ice age are quite small. The changes in orientation of the Earth toward the Sun are nowhere near enough to cause temperature changes that bring the planet out of an ice age. There absolutely have to be positive feedbacks that keep the warming going so that the ice sheets retreat. This view (and I trust the math for the initial forcing changes is correct) means that CO2 rise or something else has to be driving the warming.
So then we get into the physics of CO2 as a greenhouse gas. The physics sound simple enough that I figure they are correct. From when Svante Arrhenius first calculated the CO2 greenhouse effect in 1896 to now when the modeling is done with supercomputers the answers haven't changed by much.
I am also reading Fred Pearce's With Speed and Violence: Why Scientists Fear Tipping Points in Climate Change. He says the climate models do not include tipping points because the scientists do not know how to model tipping points which cause sudden changes. Yet the climate modelers he talks to all think there are tipping points and they are very worried about the tipping points in our future. The modelers agree that the models aren't that good. But they do not see this as a reason not to worry about climate change. Rather, they take the view that even higher range IPCC projections are conservative best cases because tipping points with sudden onset of rapid positive feedbacks will make things much worse.
The paleoclimate history does have lots of sudden climate shifts in it. So big positive feedbacks appear to kick in.
What I'm watching for now: reports of how fast the mid-Pliocene heated up to 2 degrees C over where we are today. That's the nightmare scenario. The oceans were 25 meters (about 80 feet) higher than today. That'd take out most of Florida among other places. I think we'd do climate engineering with silicon dioxide or sulfur aerosols to prevent that outcome.
Randall Parker: I agree with the need to study and to self-educate, but Hansen, in particular, is a somewhat compromised source. He's become very political which has been shown to create a tendency to skew opinions away from a clear devotion to the data. Moreover, "big positive feedbacks," actually bifurcations in chaotic dynamic systems, do occur, but predictions of future states in those same systems are inherently impossible and proven so.
Finally, I offer this story from the Guardian on sea level change that shows how quickly the science can change: http://www.guardian.co.uk/environment/2010/feb/21/sea-level-geoscience-retract-siddall
I agree that we need to study climate engineering, but only to ensure we have a useful tool at hand. I suspect the political objections to use, however, will make anticipatory use as impossible as climate prediction.
LAG, Hansen has become political? What do you mean by that? He advises the public on the consequences of his research findings. Back in the 1950s some medical researchers started telling the public that they should stop smoking cigarettes because cigarettes cause cancer and many other diseases. When the researchers started doing this did they lose their clear devotion to the data? Did their opinions become dubious?
The political tactics now being used against the climate researchers are the same tactics that Hill & Knowlton pioneered for the tobacco industry in the 1950s and 1960s. I'm also reading a book called Doubt is Their Product: How Industry's Assault on Science Threatens Your Health which describes how in a number of cases industries have managed to muddy the waters and throw doubt on research that identified threats to the public. Enlightening.
Positive feedbacks and predictions: Sure, hard to predict. But I do not see that as a reason for complacency. The modelers believe that their models are making conservative predictions because they do not include the possibility of sudden violent shifts. Yet at the same time they think sudden shifts into new states are quite possible and point out these shifts have happened in the past. At the end of the Younger Dryas 11,000 years ago the atmosphere warmed by 9F in just 10 years. Imagine that happening today.
The Guardian story: This is how science works. Lots of papers correct earlier papers and challenge earlier results. Researchers look for flaws in their own work and in the work of others. Good for them.
Randall, the problem is that, at this point, we're being asked to make multi-trillion dollar economic changes, and invest groups with vast power, on the basis of modeling software which hasn't been validated to the level you'd expect for a normal bit of commercial software, where far less is at stake. The basic science, the science that has any claim to being uncontroversial, isn't enough to get you to the scary predictions. And nobody should have so much trust in the science that does get you to those scary scenarios.
The discussion can't go on as though Climategate never happened. Maybe the science is good, maybe it isn't, but "trust me" doesn't work anymore. Given how much is at stake, it never should have.
It's all got to be redone, in the cold light of day, before anything more goes forward.
Any luck with that logarithmic vs linear issue?
The basic science can get you pretty far. What amazes me as I read books about climate is just how old the idea is that CO2 will warm up the planet. Svante Arrhenius spent over a year starting in December 1894 doing the first calculations on how much a doubling of CO2 would heat the planet. He very laboriously divided up the planet into small sections and tried to come up with albedo numbers and other numbers for each section. His results aren't far from the far more complicated models of today.
Climategate: Did it scratch Hansen's reputation? Nope. Did it scratch the reputation of the guy who first figured out how CFCs eat away the ozone (Nobel chemist Paul Crutzen)? Nope. There's a very large number of scientists engaged in climate research with very impressive resumes of past discoveries on other questions to their credit. Are these guys all morally questionable? Nope. These are first class minds.
If you don't want to or are unable to take the time to learn in depth you really are in the position of having to trust. Itrust a bunch of NAS members and Nobelists over TV talking heads or hired guns of the oil industry.
Validating normal bits of commercial software: That's not done very well for most of it. The economics works against very in depth verification and validation.
But climate models aren't our only source of evidence. I see a few main legs. First off, there's the paleoclimate history. It is very interesting and I continue to learn more and more of it. Then there's measurements of what's going on today. Shrinking accelerated glaciers, discoveries of large rivers at the bottom melting glaciers, warmer currents showing up in Greenland fjords, atmospheric gas measurements, etc.
I agree, the basic science can get you pretty far. It just can't get you into "OMG, it's a freaking emergency!" territory. That takes modeling, and the models are all fairly dodgy at this point, and dependent on data of questionable reliability.
Given the absurdly enormous interventions being advocated, it's not unreasonable to demand that climate science be put on a transparently reliable basis before it become the basis for policy. It's not enough to be right, you've got to be right in a way which gives people some reason to BELIEVE you're right.
"It's not enough to be right, you've got to be right in a way which gives people some reason to BELIEVE you're right."
I'll go out on a limb here, but how about this as a metric: Accurate predictions.
If your hypothesis, model, whatever, fails to predict outcomes accurately, it fails.
That, I believe, is the essence of falsifiability. And precisely the point where current climatological computer games fail.