A little late starting this month’s open thread – must be the weather…
Reader Interactions
435 Responses to "Unforced variations: Feb 2014"
wheelsocsays
I posted a question which got buried at the tail end of the last thread, but I’d really appreciate some responses so here it goes again:
Somebody described the field as “a mess” and brought up the idea of CO2 fertilization specifically. The general claim is that we don’t know how big of an effect it is and can’t account for it if we can’t quantify it. The conclusion seems to be that all previous dendro-based reconstructions of temperature have a bias which makes the past look colder since CO2 concentrations were lower, hence slower-growing trees than in recent times.
I’ve been trying to find out whether this is the case, but I can’t read any paywalled articles, so I can’t access much.
1) I know CO2 fertilization has been proposed in the literature as a confounding factor when interpreting some records. What’s the current prevailing opinion on its significance? How good are we at taking into account?
2) I know sampling sites are chosen to try and limit the number of confounding factors, i.e. studies about precipitation look for trees stressed mostly by water availability. How is the potential fertilization from atmospheric CO2 concentrations controlled for when selecting sites for tree rings that are used as proxies for temperature?
3) Some recent research indicates that enhanced CO2 availability increase the efficiency of water use by trees, because it’s easier to pull sufficient amounts of the gas from the atmosphere without having to leave their stomata open and let water escape. That seems to be subtly different from a direct “CO2 fertilization” effect, where carbon dioxide is simply the limiting factor to growth because there’s not enough of it. Not the same issue? Different implications for interpreting dendro data?
4) What else should I know about this, and where can I look?
It needs to be said that I trust scientists know what they’re doing and why, especially if they’re experts in a particular field. This is just an argument that piqued my curiosity, and now I have the “want to know more” bug about it. It’s beyond my layman’s knowledge about the minutia of dendroclimatology.
Thanks in advance.
Dean Myersonsays
Thought folks might be interested in an Economist article that discusses impacts of warming. Tidbit: “In America, each additional day above 32 deg C raises the annual age-adjusted mortality rate by 0.1% relative to a temperate day (10-15 deg C). In India, the rate increases by 0.8%”
Thought that folks might be interested in an article in the Economist on the impacts of warming. Tidbit: “In America each additional day above 32 deg C raises the annual age-adjusted mortality rate by 0.1% relative to a temperate day (10-15 deg C). In India the rate increases by 0.8%”
for wheelsoc, in case you’re not already looking with Google Scholar: http://scholar.google.com/scholar?as_ylo=2014&q=enhanced+CO2+availability++efficiency++water+use+trees+&hl=en&as_sdt=0,5
(that example uses the limit to only 2014 papers, just as an example; the most useful amateur approach I’ve found is to read in the “cited by” or “citing papers” to follow any interesting idea forward in time. Often on blogs someone mentions a single study as though it were the only information; digging helps)
The modernisers say that their approach could involve a fall in GDP, as they press for a more efficient approach to the use of energy, but said that illustrated some of the problems with the standard economic measure.
Sandys said: “If energy prices go up, which they have, GDP goes up. If we reduce our energy consumption, or we bear down on the price, GDP will go down but our margin will go up. If you spend a pound on energy it is a very dead pound.
“More subtle but possibly more powerful long-term impacts may result from an effect of heat on fetal and child development.” Link
The PETM suggest a lot of dwarfing, and that is what we can observe already.
“Species in the North Sea decreased in length by up to 29% over nearly four decades as water temperatures rose” Link
Dan H.says
wheelsoc,
For a detailed explanation of the effect, read the following: http://www.fao.org/docrep/w5183e/w5183e06.htm
CO2 fertilization is a known effect, and will occur in absence of another limiting factor. The fertilization effect has been shown to be greater at higher temperatures, both by the direct interaction between the two and the indirect reaction of increasing the growing season. Local precipitation increases would also lead to increased growth, as would the greater water use efficiency.
Effects are not uniform, as individual species react differently, and specific lcations have confounding effects. I have attached a few links. The first three are abstracts (paywalled), but the last two contain the full (albeit rather long) reports.
Wheelsoc, besides Hanks (as always) excellent suggestion, a good go to for countering denialist nonsense is Skeptical Science where they have a list of the common talking points of the pseudo-skeptics and brief responses to each with references to the scientific literature. Here’s the one that looks most relevant to your query: http://www.skepticalscience.com/co2-plant-food.htm
Steve Metzlersays
“must be the weather…”
You want to see it on this side of the pond. Here in Ireland, the precip was 60% above average in January, with some of the worst affected areas over 100% above average. There’s a reason why Ireland is green, but this is ridiculous. 3 cities here are underwater, and it’s even worse in parts of the UK. Now they’re talking about 2 more weeks solid of the same, with 5m storm surges expected in the SW of Ireland tonight.
SecularAnimistsays
Speaking of the weather, I actually have a climate science question.
How long before Arctic amplification causes the Jet Stream to completely collapse, and what will happen then?
Mike Ssays
There is an interesting article in Science News about modeling fish populations. According to the article the researcher. “George Sugihara, a theoretical biologist at the Scripps Institution of Oceanography,” uses a new method to deal with chaos. It occurred to me that his ideas might be applicable to near term regional climate modelling. There is an interesting discussion about the difference between chaos and randomness that could be help helpful in communicating complex modeling issues to the public. Here is a link.
Or Google “Tomorrow’s catch Chaos theory’s potential for fisheries management”.
siddsays
Phillips(2013)
doi:10.1002/jgrf.20079
shallow ice model ice model that explicitly includes latent heat transfer by meltwater (CHW is cryo-hydrologic warming). The heat dumped into the ice raises its temperature and softens it, and makes areas of the bed temperate, rather than frozen.
From the abstract:
“The base case CHW simulations reproduce the observed increase in inland ice velocity between 2001 and 2007 reasonably well. The no CHW and surface CHW simulations significantly underestimate observed ice surface velocities in both epochs. The higher ice velocities in the base case CHW simulations are attributable to both decreased basal ice viscosities associated with increased basal ice temperatures and an increase in the extent of basal sliding permitted by temperate bed conditions. Only the temperate bed extent predicted by the base case CHW simulation is consistent with independent observations of basal sliding.”
As they point out: “For every 1% by ice sheet volume of water retained, the ultimate ice warming potential after full refreezing is ~1.8 C”
They describe a simple Gedanken where CHW increases the flow parameter (presumably in Glen’s law by a factor of three.
Apart from the shallow ice approximation, there is a steady state treatment, which may not be justified. “While the one-time computation of the momentum and mass balance equations is readily justified for a snapshot in time, the use of a steady state energy equation may be inaccurate, because thermomechanical transients induced by CHW persist over time scales of the order of one to three decades [Phillips et al. 2010]. We fully acknowledge that the steady state assumption is a limitation in the computations for the cases with CHW”
Is anyone aware of other approaches to CHW in models that use, say, the full Stokes rather than shallow ice approximation ; or do better than the steady state approximation. Don’t get me wrong, I like this paper a lot, and i hope more ice models will explicitly incorporate CHW, rather than parametrizing by melt area and other such approximation. I think that some firn models already do, but i am not aware of previous efforts to explicitly extend meltwater thermal effects into the ice body as is done here. The matter interests me even more in light of the perennial water body in snowpack recently discovered in Greenland.
sidd
wilisays
I’d ike to second and elaborate on SA’s excellent question at #9: “How long before Arctic amplification causes the Jet Stream to completely collapse, and what will happen then?”
Do we get a two-cell system? What would this look like? Would it actually extend the polar vortex even further south, bringing even more bitter winters to even more southerly climes? How stable of a system would that be? Would it quickly move to a one-cell system? Are we seeing the first inklings of any of this with some of the current weather weirdness? Do we really know? (Thanks ahead of time for any light thrown on this important question, and thank again to SA for raising it.)
Nick Mannysays
Claquin et al (2003) (link: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.12.5536&rep=rep1&type=pdf), investigating LGM climate, discuss and attempt to quantify radiative forcing due to atmospheric dust ~21kya. They write that “[Increases in the potential dust source areas] are to be expected, due to effects of low precipitation and low atmospheric (CO2) on plant growth.”
Claquin et al’s model-derived findings show a change in tropical atmospheric forcing of “–2.2 to –3.2 W m–2” between PI and LGM earth, due to the increased albedo of atmospheric dust. Despite confining that value to the tropics and giving no value for the mid-latitudes between 23.5 and 45 degrees N and S, this is quite a significant amount of forcing when compared to the direct global longwave forcing difference of -2.0 W m-2 between PI and LGM due to CO2, considering the disproportionately large amount of TOA insolation over the tropics.
CO2’s effect of stimulating plant growth and increasing plant tolerance of aridity contributed to revegetating large areas of land that were desert at the LGM, compounding the effects of an increase in atmospheric humidity, reduced land/ocean surface ocean ration, and increased warmth, all of which combined caused the reduction of airborne dust and atmosperic albedo.
My question is, is there any research that gives an estimate as to the potential climatic effect of CO2 via the stimulation of plant growth and increased plant tolerance of aridity in a post-industrial, doubled CO2 atmosphere? If CO2 in the Anthropocene atmosphere contributes to re-vegetating currently arid areas as it did post-LGM, we should expect an even greater warming feedback from CO2 than is assumed from water vapor and albedo feedbacks, due to decreased global dust-induced albedo and increased water vapor from transpiration over increased vegetated area. Are there any climate models or studies that include this potential effect?
Barnes, E. A. (2013), Revisiting the evidence linking Arctic ampli- fication to extreme weather in midlatitudes, Geophys. Res. Lett., 40, doi:10.1002/grl.50880.
“I’d like to second and elaborate on SA’s excellent question at #9: “How long before Arctic amplification causes the Jet Stream to completely collapse, and what will happen then?”
For the record, I’d like to third your second and place extra emphasis on your follow up to the question at #9…
WHAT WILL HAPPEN THEN??? (Added Emphasis, mine)
It really is a good question and I’m not trying to make light of it. I would like to know too.
A question re. the ‘stagnation’ issue. I’ve read that we now have a slightly positive linear trend even when measuring starting 1998 – but consider that a rather weak rebuttal. Is it fair to say that there is not nearly a stagnation because temperatures on the southern hemisphere have generally gone up, as have temperatures in summer on the northern hemisphere – and only winter temperatures in the northern hemisphere have somewhat sharply declined? So three out of four are rising and one is falling (quite well explained by natural variability and ENSO). That’s no ‘stagnation’ at all in my book. Fair argument or am I messing something up?
Dwight Mac Kerronsays
I wonder if Mother Jones will interview anyone who will contrast the Massachusetts of 1850 to the Massachusetts of 2014. Yes, it was colder then, and American Chestnuts were a major source of nutrition and lumber, but there was far less forest. Deer, turkeys, wolves, moose, and black bears were almost extinct in the state. Yes, there were more rabbits, grouse, passenger pigeons, and probably meadowlarks, but less of just about everything else. Sometimes this glass is half full mentality seems half true… at best.
patricksays
New York’s former mayor, Mike Bloomberg, said he plans to spend his post-political career helping the United Nations with the “very difficult” and “frustrating” work of herding leaders towards a global climate deal.
Bloomberg, who was named UN special envoy for cities and climate change last week, told a conference call he sees his next mission as getting leaders on side for a global climate deal.
acquired January 19, 2014 download large image (5 MB, JPEG, 4000×4000)
acquired January 19, 2014 download GeoTIFF file (29 MB, TIFF)
On January 19, 2014, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image of a bloom of microscopic organisms off the southeastern coast of Brazil. Note how the waters of the South Atlantic are darkened in patches stretching as much as 800 kilometers (500 miles) from south to northeast across the continental shelf. In the image, the puffy strands of white over the sea and inland are clouds.
Biologists working in the area have identified the bloom as Myrionecta rubra (previously known as Mesodinium rubrum), a fast-swimming ciliate protist. Though it is not a true phytoplankter, it is an autotroph; that is, it makes its own food. Myrionecta fuels itself by photosynthesis, but it does so by ingesting chloroplasts (chlorophyll-bearing plastids) from other algae. Aside from threatening the microscopic algae it consumes, Myrionecta rubra is not known to be toxic to other marine life or humans.
Viewed close-up, these blooms have a deep red color. But this bloom appears nearly black in the satellite image because of how the ocean scatters and absorbs sunlight. Myrionecta rubra blooms tend to float a meter or two below the water surface, so whatever photons of red light they are reflecting are likely being absorbed or scattered on their way back to the surface.
Closer to shore—look near Rio de Janeiro and Sao Paolo—the water has a green tint, perhaps signs of a different bloom of phytoplankton or of sediments stirred up by recent flooding in the region.
Related Reading
Crawford, D.W. (1989) Mesodinium rubrum: The phytoplankter that wasn’t. Marine Ecology Progress Series, 58, 161–174.
Encyclopedia of Life Myrionecta rubra: overview. Accessed January 29, 2014.
NASA Earth Observatory (2010, July 13) What are Phytoplankton?
Owen, R.W., Gianesella-Galvao, S.F., and Kutner, M.B.B. (1992) Discrete, subsurface layers of the autotrophic ciliate Mesodinium rubrum off Brazil. Journal of Plankton Research 14 (1) 97–105.
Skeptic Wonder blog (2010, June 26) Criminally photosynthetic: Myrionecta, Dinophysis and stolen plastids. Accessed January 29, 2014.
NASA Earth Observatory image by Jesse Allen, using data from the Land Atmosphere Near real-time Capability for EOS (LANCE). Caption by Michael Carlowicz, with interpretation from Aurea Maria Ciotti, Universidade de São Paulo, and Norman Kuring, NASA Ocean Color Group.
My question is. Being that these critters have a red tinge, in spite of looking black on film, would they tend to warm the water that they are in? If warming seas have contributed to these blooms it would stand to reason that their red color would be a positive feed back loop to further warm the surface waters for their kin, as well as their chlorophyl pray? Now that man has killed a majority of the whale filter feeders there is little predation to keep this feed back at bay.
Adam R.says
Yeah, Dwight, because Massachusetts is a good proxy for the whole planet, right? Right?
SecularAnimistsays
Hank Roberts wrote: “Questions of the form ‘how long until you stop …’ presume.”
Yes. I do indeed presume that the rapid warming of the Arctic is already affecting the Jet Stream, and thereby affecting the Northern Hemisphere’s weather, and that continued rapid warming of the Arctic will cause the Jet Stream to slow and weaken to the point of collapse, possibly in the not-too-distant future.
Thanks for the link. I have read that article, and I’m aware of the dialog on this issue between Jennifer Francis and Steven Vavrus on the one hand, and Elizabeth Barnes on the other, and I presume that Francis, Vavrus et al are correct.
I’m interested in hearing the views of vastly more knowledgeable people than myself as to what we might expect and when, if Francis & Vavrus are right; and equally interested in hearing reasons that they might be wrong.
To Wheelsoc, to explore your queries (comment 1 in this thread) about CO2 and tree growth, you could go to http://rstb.royalsocietypublishing.org/content/367/1588/601.full.pdf see figure 6 (amongst other information) that would interest you. The paper also cites a number of modelling and empirical papers that are of relevance to your questions, like Pagani, M., Caldeira, K., Berner, R. & Beerling, D. 2009 The role of terrestrial plants in limiting atmospheric CO2 decline over the past 24 million years. Nature 460,85–8; Kgope, B. S., Bond, W. J. & Midgley, G. F. 2010 Growth responses of African savanna trees implicate atmospheric [CO2] as a driver of past and current changes in savanna tree cover. Aust. Ecol.35, 451–463; Prentice, I. C., Harrison, S. P. & Bartlein, P. J. 2011 Global vegetation and terrestrial carbon cycle changes after the last ice age. New Phytol.189, 988–998.
siddsays
i see that Munchow has a new paper on the Petermann glacier at icyseas.org (he has kindly made it freely available)
From the Abstract:
Ice shelf velocity is 15-30% larger than pre 2010 extimates.They see 5Gton/yr basal melt, 1 GTon/yr surface melt + sublimation, and 4GTon/yr from ice shelf thinning.
The figures anong other interesting things, detail the retrograde bed slope.
From the conclusions
“Following the 2012 calving event, PG ice shelf was shorter than in any previous measurements since the first records from 1876. We find spatially averaged melt rates of 10-13 m/yr, consistent with those reported by Rignot and Steffen (2008) and modeled by Gladish et al (2012). This rate exceeds the value required for steady-state mass balance (∼7-8 m/yr ), resulting in net thinning of 3-5 m/yr during the 2003-2010 period.”
sidd
Mike Ssays
@prokaryotes 24: Here is a more detailed look at the issue around the CCS project that was terminated in Norway.
Dwight Mac Kerron, you remind me of the joke about the guy who fell off the skyscraper: as he passed the 5th floor, he said “so far, so good”.
Bruce Coppolasays
Let’s get to brass tacks. I’m in the upper Midwest (Michigan, specifically). Is the pattern we’ve seen this Winter here likely to repeat with some regularity? Because if so, I need to buy a bigger snowblower.
I am only partly in jest here!
rabbitsays
Prokaryotes:
Regarding the extinction of humans…
Even as far back as the stone age, mankind had spread to every continent save Antarctica. I can think of no other vertebrate species that had accomplished this.
Furthermore, mankind was living in every conceivable habitat, including forest, jungle, alpine, desert, marsh, grasslands, coastal, and arctic.
This suggests that humans are exceptionally adaptable and resilient.
Dwight Mac Kerronsays
I must admit to Adam and Mal that crises certainly can arise here in the best of all possible worlds. Why just today, a flock of robins was outside eating bittersweet berries off the vines that have grown thirty to forty feet up the red maples and choke cherries. Now we know that it’s not right that there are robins here and even worse that there is oriental bittersweet for them to eat. But at least there was a half foot of snow to set off their colors.
Alas, for so many activists, if there is not bad news, then there is essentially no news.
Rabbit, in past times there wasn’t a global drastic change and deglaciation event of this magnitude we experience today, on a global scale. We deal with PETM 2.0 (PETM on steroids). There will be rapid simplification of civilisation, a fundamental response from the geosphere, then you have disease spread, species extinctions, food chain collapse and so on. Basically everything we call our home will be destroyed or a profoundly altered and not in a positive sense.
And then we don’t really can say how far the ozone layer might be affected or the oxygen content of the atmosphere. When we mention the extinction of the human species we need to account for the time frame – which stretches several thousands years.
Maybe theoretically some arcs could be sophisticated enough and intelligent enough managed to sustain conditions for survival. There are a lot of constructs how the species could survive, but based on the current state of affairs nobody seems to be in charge of things and we still run in circles about how to introduce better gas mileage or 10% “More ambitious” emissions targets, but which do not comply with dangerous thresholds.
Burning all fossil fuels, we conclude, would make most of the planet uninhabitable by humans, thus calling into question strategies that emphasize adaptation to climate change.Link
Adam R.says
“Activists,” Dwight? Is that what you call scientists who mark the precipitous decline of diversity in the natural world?
I think your true colors are flying high at the mizzen, Dwight, and your pose as a seeker of knowledge is sinking fast.
For Bruce Coppola: check your local history and see if this fits: https://xkcd.com/1321/
flxiblesays
“I need to buy a bigger snowblower”
Not unless you can find a pedal operated one, better to buy a good shovel and get the exercise.
Not jesting at all. ;)
wilisays
To brer rabbit at #37, who opined: “This suggests that humans are exceptionally adaptable and resilient.”
Indeed we are. But we are now entering a world with atmospheric CO2 levels that never existed any time in the entire history of our evolution as modern humans. And we are pushing far, far past this threshold as we type. The combination of increased heat and increased water vapor means that we could start seeing areas that are incompatible with human existence based on ‘wet bulb temperatures’ perhaps in just a few decades. Long before that, agriculture becomes very, very problematic. Also note that human flesh is now the largest, most massive (mostly) unexploited uniform food source on the planet…and nature does not long tolerate and unexploited food source for long.
Some dozens of species are probably going extinct right now every day. We should be humble enough to remember that our entire race is, after all, only one more species. Should we expect that every other species can go poof, but our can never conceivably do so?
Hank & Fixable: Yep, love XKCD and have seen that one. And yes, it fits; didn’t need to look up history because I’m old enough to remember. I am not questioning climate change at all.
I recognize the irony of posting about getting a bigger, fossil-fuel burning machine here, but I’m not young anymore and a shovel for heavy snows simply isn’t practical, alas. I’m pretty good at endurance but not so much on upper body strength. And there’s a paucity of willing teenage labor in my neighborhood. :)
I do honestly wonder if the effects on polar circulation discussed above means a return, if temporary, to the “old normal” of Winter in the northern US.
Ray Ladburysays
Bruce,
If upper body strength is the issue, a bigger snow blower might not be the answer. The bigger the machine, the more they tend to buck. Might I suggest paying a neighbor kid to shovel your drive? Lost a good friend who didn’t want to give up clearing his drive. At some point, you’ve earned the right to leave the exercise to the young and hungry.
Dwight Mac Kerronsays
#40 Adam, Your response is duly noted. I learned a long time ago that when you challenge a warmist or a denier (or even mention those words ;-) the fur starts flying and EITHER side will accuse you of being one of those guys on the other side. Call me a skeptic; is that the flag you see? ;-)
I have read Thoreau’s journals extensively enough to know that we do have significantly earlier flowering and last spring frost dates than he had in the 1850’s and we also have later first frosts in the fall, which gets us back to my point about the expanded growing season here. The journals are also one reason I know about the diversity of forest and large mammal wildlife that he did not have, but I have also seen pictures of my home town community when it was 90% fields. Now, there are a lot more trees, as well as thousands of automobiles.
I suppose if I had to define activist it would come down to a descendant of Jonathan Edwards, a member of the tribe who knows that there is sin and imperfection in the world, and by God or Gaia, they are going to do tell you about it, possibly rather than planting their own gardens. I believe in diversity enough to find a place in the world for activists, but getting a lot of their mailers, I can tell you that there is no shortage of crises (or sin, I’m sure) in the world and apparently I should REPENT and DONATE.
Hank, thank you for the robin charts. I first saw winter robins in cedar copses of grown-in pasture, a couple miles away, thirty years ago. Now we have enough cedar and bittersweet so that we have our own little flock, or at least a regularly visiting flock. Humans have taken to disrupting nature by putting hundreds, if not thousands of tons of bird seed out into feeders, but then, we have cats as well. Tsk, tsk.
Dan H.says
Bruce,
I have the same problem in the same location. However, being an avid skier (both downhill and cross-country), I am particularly enjoying this winter. I have probably gotten more winter exercise this year than the last three combined, including clearing my driveway every other day.
The likelihood of a repeat performance next year (or the near future) appears slim. We have experienced this weather pattern about once every decade. On occassion they cluster (late 70s), but most often, they are individual outliers (1993). Weather is chaotic, especially in Michigan.
Adam R.says
@#47 Dwight:
More anecdotes from Massachusetts, I see. Your point is what, exactly? That things in our natural world will somehow be fine if these silly “activists” would just shut up and leave people alone? Activists being a tribe which, apparently by your lights, includes any scientists publishing research on the worldwide mass extinction now measurably in progress.
When I mentioned the flag you have unfurled, I meant that of the peculiar sort of climate science denier–and in your case, broad-spectrum environmental science denier–who says “OK it’s happening, but it’s nothing to worry about because, look, a black bear! In Massachusetts!” It’s the same dodge used by people who find one glacier out of hundreds that’s growing instead of receding and smugly conclude that global warming is therefore nothing to worry about.
You can’t come to RealClimate with your faux-reasonable tone and expect to get away with it. People here have seen every species of denier over the years and your sort is nothing new. But go ahead, comment more if you feel like it. You might get in a couple more before you get permanently bore-holed. Link some pictures of black bears in Cambridge next time; that would be cute.
Nick O.says
#10 Steve -just backing up your point about how wet it is over this side of the pond, have a look at the Beeb yesterday, and a Met Office report, re. the continued flooding in the SW of England and Wales, particularly in Somerset (where the authorities advised 4 villages to be evacuated last night owing to severe flood risks): http://www.bbc.co.uk/news/uk-26050452 http://www.metoffice.gov.uk/climate/uk/interesting/2013-decwind
#1 – wheelsoc – one thing to bear in mind about the possible benefits of CO2 fertilisation is that the effects are not easily averaged, particularly if you take into account ocean acidification. So it’s all pretty much swings and roundabouts, within an overall warming trend. Whether it’s also a ‘storming’ trend as well (i.e. it’s getting stormier), well, the jury is out on that one, and I suspect will be for some time yet.
I posted a question which got buried at the tail end of the last thread, but I’d really appreciate some responses so here it goes again:
Somebody described the field as “a mess” and brought up the idea of CO2 fertilization specifically. The general claim is that we don’t know how big of an effect it is and can’t account for it if we can’t quantify it. The conclusion seems to be that all previous dendro-based reconstructions of temperature have a bias which makes the past look colder since CO2 concentrations were lower, hence slower-growing trees than in recent times.
I’ve been trying to find out whether this is the case, but I can’t read any paywalled articles, so I can’t access much.
1) I know CO2 fertilization has been proposed in the literature as a confounding factor when interpreting some records. What’s the current prevailing opinion on its significance? How good are we at taking into account?
2) I know sampling sites are chosen to try and limit the number of confounding factors, i.e. studies about precipitation look for trees stressed mostly by water availability. How is the potential fertilization from atmospheric CO2 concentrations controlled for when selecting sites for tree rings that are used as proxies for temperature?
3) Some recent research indicates that enhanced CO2 availability increase the efficiency of water use by trees, because it’s easier to pull sufficient amounts of the gas from the atmosphere without having to leave their stomata open and let water escape. That seems to be subtly different from a direct “CO2 fertilization” effect, where carbon dioxide is simply the limiting factor to growth because there’s not enough of it. Not the same issue? Different implications for interpreting dendro data?
4) What else should I know about this, and where can I look?
It needs to be said that I trust scientists know what they’re doing and why, especially if they’re experts in a particular field. This is just an argument that piqued my curiosity, and now I have the “want to know more” bug about it. It’s beyond my layman’s knowledge about the minutia of dendroclimatology.
Thanks in advance.
Thought folks might be interested in an Economist article that discusses impacts of warming. Tidbit: “In America, each additional day above 32 deg C raises the annual age-adjusted mortality rate by 0.1% relative to a temperate day (10-15 deg C). In India, the rate increases by 0.8%”
http://www.economist.com/climate14
Thought that folks might be interested in an article in the Economist on the impacts of warming. Tidbit: “In America each additional day above 32 deg C raises the annual age-adjusted mortality rate by 0.1% relative to a temperate day (10-15 deg C). In India the rate increases by 0.8%”
http://www.economist.com/climate14
for wheelsoc, in case you’re not already looking with Google Scholar:
http://scholar.google.com/scholar?as_ylo=2014&q=enhanced+CO2+availability++efficiency++water+use+trees+&hl=en&as_sdt=0,5
(that example uses the limit to only 2014 papers, just as an example; the most useful amateur approach I’ve found is to read in the “cited by” or “citing papers” to follow any interesting idea forward in time. Often on blogs someone mentions a single study as though it were the only information; digging helps)
http://www.theguardian.com/environment/2014/feb/03/green-tories-manifesto-challenge-climate-change-deniers
Re Dean Myerson,
“More subtle but possibly more powerful long-term impacts may result from an effect of heat on fetal and child development.” Link
The PETM suggest a lot of dwarfing, and that is what we can observe already.
“Species in the North Sea decreased in length by up to 29% over nearly four decades as water temperatures rose” Link
wheelsoc,
For a detailed explanation of the effect, read the following:
http://www.fao.org/docrep/w5183e/w5183e06.htm
CO2 fertilization is a known effect, and will occur in absence of another limiting factor. The fertilization effect has been shown to be greater at higher temperatures, both by the direct interaction between the two and the indirect reaction of increasing the growing season. Local precipitation increases would also lead to increased growth, as would the greater water use efficiency.
Effects are not uniform, as individual species react differently, and specific lcations have confounding effects. I have attached a few links. The first three are abstracts (paywalled), but the last two contain the full (albeit rather long) reports.
http://gbpihedenvis.nic.in/html/vol10_2/HIGH%20ALTITUDE.pdf
http://onlinelibrary.wiley.com/doi/10.1111/j.1469-8137.2006.01746.x/pdf
http://onlinelibrary.wiley.com/doi/10.1029/2009GB003699/abstract
http://www.ars.usda.gov/SP2UserFiles/person/3960/Morgan207CO2fertilizationWhenwhereandhowmuch.pdf
http://arizona.openrepository.com/arizona/bitstream/10150/193510/1/azu_etd_1878_sip1_m.pdf
Hope this helps.
The Mann story is being covered by CC now: http://thinkprogress.org/climate/2014/02/03/3228411/national-review-defamation/
How about adding a permanent link to his legal fund site on the right-hand column of the web page??
(reCaptcha suggests: “for mirito” whoever (s)he is.)
Wheelsoc, besides Hanks (as always) excellent suggestion, a good go to for countering denialist nonsense is Skeptical Science where they have a list of the common talking points of the pseudo-skeptics and brief responses to each with references to the scientific literature. Here’s the one that looks most relevant to your query: http://www.skepticalscience.com/co2-plant-food.htm
“must be the weather…”
You want to see it on this side of the pond. Here in Ireland, the precip was 60% above average in January, with some of the worst affected areas over 100% above average. There’s a reason why Ireland is green, but this is ridiculous. 3 cities here are underwater, and it’s even worse in parts of the UK. Now they’re talking about 2 more weeks solid of the same, with 5m storm surges expected in the SW of Ireland tonight.
Speaking of the weather, I actually have a climate science question.
How long before Arctic amplification causes the Jet Stream to completely collapse, and what will happen then?
There is an interesting article in Science News about modeling fish populations. According to the article the researcher. “George Sugihara, a theoretical biologist at the Scripps Institution of Oceanography,” uses a new method to deal with chaos. It occurred to me that his ideas might be applicable to near term regional climate modelling. There is an interesting discussion about the difference between chaos and randomness that could be help helpful in communicating complex modeling issues to the public. Here is a link.
https://www.sciencenews.org/article/tomorrow’s-catch
Or Google “Tomorrow’s catch Chaos theory’s potential for fisheries management”.
Phillips(2013)
doi:10.1002/jgrf.20079
shallow ice model ice model that explicitly includes latent heat transfer by meltwater (CHW is cryo-hydrologic warming). The heat dumped into the ice raises its temperature and softens it, and makes areas of the bed temperate, rather than frozen.
From the abstract:
“The base case CHW simulations reproduce the observed increase in inland ice velocity between 2001 and 2007 reasonably well. The no CHW and surface CHW simulations significantly underestimate observed ice surface velocities in both epochs. The higher ice velocities in the base case CHW simulations are attributable to both decreased basal ice viscosities associated with increased basal ice temperatures and an increase in the extent of basal sliding permitted by temperate bed conditions. Only the temperate bed extent predicted by the base case CHW simulation is consistent with independent observations of basal sliding.”
As they point out: “For every 1% by ice sheet volume of water retained, the ultimate ice warming potential after full refreezing is ~1.8 C”
They describe a simple Gedanken where CHW increases the flow parameter (presumably in Glen’s law by a factor of three.
Apart from the shallow ice approximation, there is a steady state treatment, which may not be justified. “While the one-time computation of the momentum and mass balance equations is readily justified for a snapshot in time, the use of a steady state energy equation may be inaccurate, because thermomechanical transients induced by CHW persist over time scales of the order of one to three decades [Phillips et al. 2010]. We fully acknowledge that the steady state assumption is a limitation in the computations for the cases with CHW”
Is anyone aware of other approaches to CHW in models that use, say, the full Stokes rather than shallow ice approximation ; or do better than the steady state approximation. Don’t get me wrong, I like this paper a lot, and i hope more ice models will explicitly incorporate CHW, rather than parametrizing by melt area and other such approximation. I think that some firn models already do, but i am not aware of previous efforts to explicitly extend meltwater thermal effects into the ice body as is done here. The matter interests me even more in light of the perennial water body in snowpack recently discovered in Greenland.
sidd
I’d ike to second and elaborate on SA’s excellent question at #9: “How long before Arctic amplification causes the Jet Stream to completely collapse, and what will happen then?”
Do we get a two-cell system? What would this look like? Would it actually extend the polar vortex even further south, bringing even more bitter winters to even more southerly climes? How stable of a system would that be? Would it quickly move to a one-cell system? Are we seeing the first inklings of any of this with some of the current weather weirdness? Do we really know? (Thanks ahead of time for any light thrown on this important question, and thank again to SA for raising it.)
Claquin et al (2003) (link: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.12.5536&rep=rep1&type=pdf), investigating LGM climate, discuss and attempt to quantify radiative forcing due to atmospheric dust ~21kya. They write that “[Increases in the potential dust source areas] are to be expected, due to effects of low precipitation and low atmospheric (CO2) on plant growth.”
Claquin et al’s model-derived findings show a change in tropical atmospheric forcing of “–2.2 to –3.2 W m–2” between PI and LGM earth, due to the increased albedo of atmospheric dust. Despite confining that value to the tropics and giving no value for the mid-latitudes between 23.5 and 45 degrees N and S, this is quite a significant amount of forcing when compared to the direct global longwave forcing difference of -2.0 W m-2 between PI and LGM due to CO2, considering the disproportionately large amount of TOA insolation over the tropics.
CO2’s effect of stimulating plant growth and increasing plant tolerance of aridity contributed to revegetating large areas of land that were desert at the LGM, compounding the effects of an increase in atmospheric humidity, reduced land/ocean surface ocean ration, and increased warmth, all of which combined caused the reduction of airborne dust and atmosperic albedo.
My question is, is there any research that gives an estimate as to the potential climatic effect of CO2 via the stimulation of plant growth and increased plant tolerance of aridity in a post-industrial, doubled CO2 atmosphere? If CO2 in the Anthropocene atmosphere contributes to re-vegetating currently arid areas as it did post-LGM, we should expect an even greater warming feedback from CO2 than is assumed from water vapor and albedo feedbacks, due to decreased global dust-induced albedo and increased water vapor from transpiration over increased vegetated area. Are there any climate models or studies that include this potential effect?
> “How long …?”
Questions of the form “how long until you stop …” presume.
Better: “if” and “how would we know whether …” questions
http://www.climatecentral.org/news/new-study-questions-arctic-warming-extreme-weather-links-16375
Barnes, E. A. (2013), Revisiting the evidence linking Arctic ampli- fication to extreme weather in midlatitudes, Geophys. Res. Lett., 40, doi:10.1002/grl.50880.
Re Steve Metzler, the study Influence of Arctic sea ice on European summer precipitation could be interpreted much broader.
Wili, my view is “the fridge” will stay open, the divide of hot and cold at the pole is gone. Weather will become even more persistent and the lack of a defined jet will affect ocean currents. That’s why i asked Does Sea Ice loss create the condition for an emerging permanent El Nino state?.
“I’d like to second and elaborate on SA’s excellent question at #9: “How long before Arctic amplification causes the Jet Stream to completely collapse, and what will happen then?”
For the record, I’d like to third your second and place extra emphasis on your follow up to the question at #9…
WHAT WILL HAPPEN THEN??? (Added Emphasis, mine)
It really is a good question and I’m not trying to make light of it. I would like to know too.
“Humans Will Eventually Become Extinct”
I try to think that somehow a few breeding pairs could survive, but i fail to see how.
Scientific indignation may be the least of Mark Steyn’s worries.
A question re. the ‘stagnation’ issue. I’ve read that we now have a slightly positive linear trend even when measuring starting 1998 – but consider that a rather weak rebuttal. Is it fair to say that there is not nearly a stagnation because temperatures on the southern hemisphere have generally gone up, as have temperatures in summer on the northern hemisphere – and only winter temperatures in the northern hemisphere have somewhat sharply declined? So three out of four are rising and one is falling (quite well explained by natural variability and ENSO). That’s no ‘stagnation’ at all in my book. Fair argument or am I messing something up?
I wonder if Mother Jones will interview anyone who will contrast the Massachusetts of 1850 to the Massachusetts of 2014. Yes, it was colder then, and American Chestnuts were a major source of nutrition and lumber, but there was far less forest. Deer, turkeys, wolves, moose, and black bears were almost extinct in the state. Yes, there were more rabbits, grouse, passenger pigeons, and probably meadowlarks, but less of just about everything else. Sometimes this glass is half full mentality seems half true… at best.
New York’s former mayor, Mike Bloomberg, said he plans to spend his post-political career helping the United Nations with the “very difficult” and “frustrating” work of herding leaders towards a global climate deal.
Bloomberg, who was named UN special envoy for cities and climate change last week, told a conference call he sees his next mission as getting leaders on side for a global climate deal.
http://www.theguardian.com/environment/2014/feb/05/michael-bloomberg-world-leaders-climate-deal
The Norwegian carbon capture and storage nightmare
The Antarctic Half of the Global Thermohaline Circulation Is Faltering
also for wheelsoc:
https://www.realclimate.org/index.php/archives/2004/11/co_2-fertilization/
I recently ran into this link and it prompted this question. Does anyone feel it needs closer attention?
lots of other great stuff over at Earth Observatory, worth a trawl, but this is pretty nasty looking:
http://earthobservatory.nasa.gov/IOTD/view.php?id=82968&src=eoa-iotd
acquired January 19, 2014 download large image (5 MB, JPEG, 4000×4000)
acquired January 19, 2014 download GeoTIFF file (29 MB, TIFF)
On January 19, 2014, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image of a bloom of microscopic organisms off the southeastern coast of Brazil. Note how the waters of the South Atlantic are darkened in patches stretching as much as 800 kilometers (500 miles) from south to northeast across the continental shelf. In the image, the puffy strands of white over the sea and inland are clouds.
Biologists working in the area have identified the bloom as Myrionecta rubra (previously known as Mesodinium rubrum), a fast-swimming ciliate protist. Though it is not a true phytoplankter, it is an autotroph; that is, it makes its own food. Myrionecta fuels itself by photosynthesis, but it does so by ingesting chloroplasts (chlorophyll-bearing plastids) from other algae. Aside from threatening the microscopic algae it consumes, Myrionecta rubra is not known to be toxic to other marine life or humans.
Viewed close-up, these blooms have a deep red color. But this bloom appears nearly black in the satellite image because of how the ocean scatters and absorbs sunlight. Myrionecta rubra blooms tend to float a meter or two below the water surface, so whatever photons of red light they are reflecting are likely being absorbed or scattered on their way back to the surface.
Closer to shore—look near Rio de Janeiro and Sao Paolo—the water has a green tint, perhaps signs of a different bloom of phytoplankton or of sediments stirred up by recent flooding in the region.
Related Reading
Crawford, D.W. (1989) Mesodinium rubrum: The phytoplankter that wasn’t. Marine Ecology Progress Series, 58, 161–174.
Encyclopedia of Life Myrionecta rubra: overview. Accessed January 29, 2014.
NASA Earth Observatory (2010, July 13) What are Phytoplankton?
Owen, R.W., Gianesella-Galvao, S.F., and Kutner, M.B.B. (1992) Discrete, subsurface layers of the autotrophic ciliate Mesodinium rubrum off Brazil. Journal of Plankton Research 14 (1) 97–105.
Skeptic Wonder blog (2010, June 26) Criminally photosynthetic: Myrionecta, Dinophysis and stolen plastids. Accessed January 29, 2014.
NASA Earth Observatory image by Jesse Allen, using data from the Land Atmosphere Near real-time Capability for EOS (LANCE). Caption by Michael Carlowicz, with interpretation from Aurea Maria Ciotti, Universidade de São Paulo, and Norman Kuring, NASA Ocean Color Group.
My question is. Being that these critters have a red tinge, in spite of looking black on film, would they tend to warm the water that they are in? If warming seas have contributed to these blooms it would stand to reason that their red color would be a positive feed back loop to further warm the surface waters for their kin, as well as their chlorophyl pray? Now that man has killed a majority of the whale filter feeders there is little predation to keep this feed back at bay.
Yeah, Dwight, because Massachusetts is a good proxy for the whole planet, right? Right?
Hank Roberts wrote: “Questions of the form ‘how long until you stop …’ presume.”
Yes. I do indeed presume that the rapid warming of the Arctic is already affecting the Jet Stream, and thereby affecting the Northern Hemisphere’s weather, and that continued rapid warming of the Arctic will cause the Jet Stream to slow and weaken to the point of collapse, possibly in the not-too-distant future.
Thanks for the link. I have read that article, and I’m aware of the dialog on this issue between Jennifer Francis and Steven Vavrus on the one hand, and Elizabeth Barnes on the other, and I presume that Francis, Vavrus et al are correct.
I’m interested in hearing the views of vastly more knowledgeable people than myself as to what we might expect and when, if Francis & Vavrus are right; and equally interested in hearing reasons that they might be wrong.
for Leif
This may help:
http://www.oceanopticsbook.info/view/absorption/absorption_by_oceanic_constituents
That’s one example of much you’ll find on your question by ‘oogling:
https://www.google.com/search?q=plankton+infrared+absorbtion
To Wheelsoc, to explore your queries (comment 1 in this thread) about CO2 and tree growth, you could go to http://rstb.royalsocietypublishing.org/content/367/1588/601.full.pdf see figure 6 (amongst other information) that would interest you. The paper also cites a number of modelling and empirical papers that are of relevance to your questions, like Pagani, M., Caldeira, K., Berner, R. & Beerling, D. 2009 The role of terrestrial plants in limiting atmospheric CO2 decline over the past 24 million years. Nature 460,85–8; Kgope, B. S., Bond, W. J. & Midgley, G. F. 2010 Growth responses of African savanna trees implicate atmospheric [CO2] as a driver of past and current changes in savanna tree cover. Aust. Ecol.35, 451–463; Prentice, I. C., Harrison, S. P. & Bartlein, P. J. 2011 Global vegetation and terrestrial carbon cycle changes after the last ice age. New Phytol.189, 988–998.
i see that Munchow has a new paper on the Petermann glacier at icyseas.org (he has kindly made it freely available)
From the Abstract:
Ice shelf velocity is 15-30% larger than pre 2010 extimates.They see 5Gton/yr basal melt, 1 GTon/yr surface melt + sublimation, and 4GTon/yr from ice shelf thinning.
The figures anong other interesting things, detail the retrograde bed slope.
From the conclusions
“Following the 2012 calving event, PG ice shelf was shorter than in any previous measurements since the first records from 1876. We find spatially averaged melt rates of 10-13 m/yr, consistent with those reported by Rignot and Steffen (2008) and modeled by Gladish et al (2012). This rate exceeds the value required for steady-state mass balance (∼7-8 m/yr ), resulting in net thinning of 3-5 m/yr during the 2003-2010 period.”
sidd
@prokaryotes 24: Here is a more detailed look at the issue around the CCS project that was terminated in Norway.
http://www.powermag.com/42579/
Dwight Mac Kerron, you remind me of the joke about the guy who fell off the skyscraper: as he passed the 5th floor, he said “so far, so good”.
Let’s get to brass tacks. I’m in the upper Midwest (Michigan, specifically). Is the pattern we’ve seen this Winter here likely to repeat with some regularity? Because if so, I need to buy a bigger snowblower.
I am only partly in jest here!
Prokaryotes:
Regarding the extinction of humans…
Even as far back as the stone age, mankind had spread to every continent save Antarctica. I can think of no other vertebrate species that had accomplished this.
Furthermore, mankind was living in every conceivable habitat, including forest, jungle, alpine, desert, marsh, grasslands, coastal, and arctic.
This suggests that humans are exceptionally adaptable and resilient.
I must admit to Adam and Mal that crises certainly can arise here in the best of all possible worlds. Why just today, a flock of robins was outside eating bittersweet berries off the vines that have grown thirty to forty feet up the red maples and choke cherries. Now we know that it’s not right that there are robins here and even worse that there is oriental bittersweet for them to eat. But at least there was a half foot of snow to set off their colors.
Alas, for so many activists, if there is not bad news, then there is essentially no news.
Rabbit, in past times there wasn’t a global drastic change and deglaciation event of this magnitude we experience today, on a global scale. We deal with PETM 2.0 (PETM on steroids). There will be rapid simplification of civilisation, a fundamental response from the geosphere, then you have disease spread, species extinctions, food chain collapse and so on. Basically everything we call our home will be destroyed or a profoundly altered and not in a positive sense.
And then we don’t really can say how far the ozone layer might be affected or the oxygen content of the atmosphere. When we mention the extinction of the human species we need to account for the time frame – which stretches several thousands years.
Maybe theoretically some arcs could be sophisticated enough and intelligent enough managed to sustain conditions for survival. There are a lot of constructs how the species could survive, but based on the current state of affairs nobody seems to be in charge of things and we still run in circles about how to introduce better gas mileage or 10% “More ambitious” emissions targets, but which do not comply with dangerous thresholds.
“Activists,” Dwight? Is that what you call scientists who mark the precipitous decline of diversity in the natural world?
I think your true colors are flying high at the mizzen, Dwight, and your pose as a seeker of knowledge is sinking fast.
For Bruce Coppola: check your local history and see if this fits:
https://xkcd.com/1321/
“I need to buy a bigger snowblower”
Not unless you can find a pedal operated one, better to buy a good shovel and get the exercise.
Not jesting at all. ;)
To brer rabbit at #37, who opined: “This suggests that humans are exceptionally adaptable and resilient.”
Indeed we are. But we are now entering a world with atmospheric CO2 levels that never existed any time in the entire history of our evolution as modern humans. And we are pushing far, far past this threshold as we type. The combination of increased heat and increased water vapor means that we could start seeing areas that are incompatible with human existence based on ‘wet bulb temperatures’ perhaps in just a few decades. Long before that, agriculture becomes very, very problematic. Also note that human flesh is now the largest, most massive (mostly) unexploited uniform food source on the planet…and nature does not long tolerate and unexploited food source for long.
Some dozens of species are probably going extinct right now every day. We should be humble enough to remember that our entire race is, after all, only one more species. Should we expect that every other species can go poof, but our can never conceivably do so?
For Dwight Mac Kerron: a chance to check in:
http://www.learner.org/jnorth/tm/robin/RobinPhenology.html
http://www.learner.org/jnorth/robin/spring2014/update012814.html
http://map.learner.org/cgi-bin/mapserv?mode=map&map=/var/www/content/jnorth/maps/robin_first_spring2014.map&mapext=-4134750.3345794394+-2383397+3223877.3345794394+4189000&mapsize=600+536&layers=This_Week
Hank & Fixable: Yep, love XKCD and have seen that one. And yes, it fits; didn’t need to look up history because I’m old enough to remember. I am not questioning climate change at all.
I recognize the irony of posting about getting a bigger, fossil-fuel burning machine here, but I’m not young anymore and a shovel for heavy snows simply isn’t practical, alas. I’m pretty good at endurance but not so much on upper body strength. And there’s a paucity of willing teenage labor in my neighborhood. :)
I do honestly wonder if the effects on polar circulation discussed above means a return, if temporary, to the “old normal” of Winter in the northern US.
Bruce,
If upper body strength is the issue, a bigger snow blower might not be the answer. The bigger the machine, the more they tend to buck. Might I suggest paying a neighbor kid to shovel your drive? Lost a good friend who didn’t want to give up clearing his drive. At some point, you’ve earned the right to leave the exercise to the young and hungry.
#40 Adam, Your response is duly noted. I learned a long time ago that when you challenge a warmist or a denier (or even mention those words ;-) the fur starts flying and EITHER side will accuse you of being one of those guys on the other side. Call me a skeptic; is that the flag you see? ;-)
I have read Thoreau’s journals extensively enough to know that we do have significantly earlier flowering and last spring frost dates than he had in the 1850’s and we also have later first frosts in the fall, which gets us back to my point about the expanded growing season here. The journals are also one reason I know about the diversity of forest and large mammal wildlife that he did not have, but I have also seen pictures of my home town community when it was 90% fields. Now, there are a lot more trees, as well as thousands of automobiles.
I suppose if I had to define activist it would come down to a descendant of Jonathan Edwards, a member of the tribe who knows that there is sin and imperfection in the world, and by God or Gaia, they are going to do tell you about it, possibly rather than planting their own gardens. I believe in diversity enough to find a place in the world for activists, but getting a lot of their mailers, I can tell you that there is no shortage of crises (or sin, I’m sure) in the world and apparently I should REPENT and DONATE.
Hank, thank you for the robin charts. I first saw winter robins in cedar copses of grown-in pasture, a couple miles away, thirty years ago. Now we have enough cedar and bittersweet so that we have our own little flock, or at least a regularly visiting flock. Humans have taken to disrupting nature by putting hundreds, if not thousands of tons of bird seed out into feeders, but then, we have cats as well. Tsk, tsk.
Bruce,
I have the same problem in the same location. However, being an avid skier (both downhill and cross-country), I am particularly enjoying this winter. I have probably gotten more winter exercise this year than the last three combined, including clearing my driveway every other day.
The likelihood of a repeat performance next year (or the near future) appears slim. We have experienced this weather pattern about once every decade. On occassion they cluster (late 70s), but most often, they are individual outliers (1993). Weather is chaotic, especially in Michigan.
@#47 Dwight:
More anecdotes from Massachusetts, I see. Your point is what, exactly? That things in our natural world will somehow be fine if these silly “activists” would just shut up and leave people alone? Activists being a tribe which, apparently by your lights, includes any scientists publishing research on the worldwide mass extinction now measurably in progress.
When I mentioned the flag you have unfurled, I meant that of the peculiar sort of climate science denier–and in your case, broad-spectrum environmental science denier–who says “OK it’s happening, but it’s nothing to worry about because, look, a black bear! In Massachusetts!” It’s the same dodge used by people who find one glacier out of hundreds that’s growing instead of receding and smugly conclude that global warming is therefore nothing to worry about.
You can’t come to RealClimate with your faux-reasonable tone and expect to get away with it. People here have seen every species of denier over the years and your sort is nothing new. But go ahead, comment more if you feel like it. You might get in a couple more before you get permanently bore-holed. Link some pictures of black bears in Cambridge next time; that would be cute.
#10 Steve -just backing up your point about how wet it is over this side of the pond, have a look at the Beeb yesterday, and a Met Office report, re. the continued flooding in the SW of England and Wales, particularly in Somerset (where the authorities advised 4 villages to be evacuated last night owing to severe flood risks):
http://www.bbc.co.uk/news/uk-26050452
http://www.metoffice.gov.uk/climate/uk/interesting/2013-decwind
#1 – wheelsoc – one thing to bear in mind about the possible benefits of CO2 fertilisation is that the effects are not easily averaged, particularly if you take into account ocean acidification. So it’s all pretty much swings and roundabouts, within an overall warming trend. Whether it’s also a ‘storming’ trend as well (i.e. it’s getting stormier), well, the jury is out on that one, and I suspect will be for some time yet.