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Kevin McKinney

Congratulations on 500, Neven!

And thanks for this one--I think. That last graph isn't so happy-making.

As an antidote, let me remark that the Canadian province of British Columbia just acquired its first Green Party MLA (Member of the Legislative Assembly.) And he's an IPCC Assessment Report lead author, several times over--Dr. Andrew Weaver.

Not a game-changer, probably, but the British Columbia Assembly will now get straight talk on climate when and as needed. That can't be a bad thing.

Sushi

The Globe and Mail published a story yoday in regard to fossil water obtained from a deep mine shaft in northern Ontario. The water has not yet been subject to a full analysis but the xenon isotope indicates it is of similar age to the fossil water described in this post.

"The water flowing out of fractures and bore holes in one mine near Timmins dates back more than a billion years, perhaps 2.6 billion, making it the oldest water known to exist on Earth, says the team that details the discovery in the journal Nature."

http://news.nationalpost.com/2013/05/15/worlds-oldest-water-bubbling-into-northern-ontario-mine/

R. Gates

Wow, 500! Thanks for the great efforts Neven...

In regard to the Lake E data, I've been a big fan of looking at Paleoclimate data for the most accurate assessment of what the "sum of all feedbacks" will be for the Earth system level of sensitivity to a doubling of CO2. I think Hansen is exactly on target here in suggesting that the feedbacks (both negative and positive) are just too darn complicated for the models to really give us the most accurate idea of what will happen at 560 ppm. We just don't have the math and dynamics right to model things right. The complete and utter failure of the models to predict the rapid Arctic sea ice decline is the prime example of this.

The Lake E sediment data is one of the cleanest looks back into the Plicene we'll ever get. Because it represents the "sum of all feedbacks" at the time for 400 ppm CO2, we know it can be trusted as giving the full story. Now granted, other variables may have been different back then such as ocean currents, etc., but overall, the Lake E data tell us pretty convincingly that when you hit around 400 ppm, you're going to get a much warmer Arctic. The real problem is, it probably took centuries back then for the CO2 to settle on 400 ppm, but we've blasted up there so fast, that we're likely to even get more bizarre climate reactions, not to mention the fact that 400 ppm is just a stopping point as the Human Carbon volcano continues to erupt with much vigor...

Craig Merry

I don't see how we're not on track for changes in the next 30 years. I hope we can adapt without much consequence on ourselves and the planet we call home.

Ac A

Craig,

we can adapt without much consequence on ourselves and the planet -- I am afraid, this is already not happening,

Alex

nowayout

Today it is not the Milankovic slow motion change recorded at El'gygytgyn. The system responses take their time, but I am not convinced that our massive CO2 impact within a geologically neglegible time period will not change the course of events bound to former Milankovic cycles.

E.g. how far away are we from massive Methane release events?

We are at 400 ppm, but we are far from finished. And one can doubt whether we are in charge anyhow already at this point.

Steve Bloom

Congrats, Neven! It's quite the milestone.

Just to be clear, the video discusses a phase of research prior to the current paper.

Alex, are those your graphics? In any case the second one showing a +8C rise by 2100 is misleading in that there's no basis for saying what date it will happen by. Also note that the +8C is specifically for the Lake E site, which is a somewhat continental location on the edge of the Arctic and so on the low side for an Arctic average.

Steve Bloom

Here's a new paper bolstering the view expressed in the video that Arctic sea ice isn't likely to be very persistent in the face of the blowtorch we're currently applying to it. Title/abstract:

The amplification of Arctic terrestrial surface temperatures by reduced sea-ice extent during the Pliocene

Many past warm periods exhibited greatly reduced latitudinal temperature gradients as a result of amplified Arctic surface temperatures as well as more seasonably equable temperatures. The Pliocene is a period of particular interest because CO2 forcing was comparable to today and yet Arctic temperatures were significantly warmer than today. Here we describe an atmospheric general circulation model experiment assessing the response of terrestrial temperatures in the mid-Pliocene (3.02 to 3.26 Ma) to an ice-free Arctic, and we compare the simulation with a compilation of proxy-based Pliocene paleotemperature reconstructions. Our experiments indicate that the amplification of Arctic surface temperatures is much more sensitive to the extent of sea ice than continental ice. The removal of Arctic sea ice results in simulated mean annual surface temperatures that better match terrestrial proxy data (RMSE = 2.9 °C) than experimental conditions that included seasonal sea ice (RMSE = 4.5 °C). Our simulations also show a decrease in the seasonal amplitude of temperatures in the absence of sea-ice, which is consistent with theory predicting more equable climates in the Arctic during warmer intervals in Earth’s history. Our results demonstrate that once sea-ice is removed, latent heat is lost from the ocean to the atmosphere as water vapor that can be circulated by the atmosphere and result in warming of continental interiors. Although our sensitivity experiment does not help to identify the full array of feedback mechanisms responsible for the amplification of Arctic surface temperatures during the Pliocene, it does demonstrate that Arctic terrestrial surface temperatures are extremely sensitive to the spatial and seasonal extent of sea-ice.


Ac A

Hi Steve,

yes, I produced those graphs provided by data from the paleo-reconstructions, NOAA instrumental Arctic temperatures, and 8°C as revealed by lake E sediments.

Of course, that 8°C is just graphical representation of the rise - the year 2100 was chosen arbitrarily (the rate of change is around 0.08°C/year (almost 2x faster than current 0.04-5C°/year). You may argue it's over-estimate or under-estimate for the whole Arctic region, thus the red line added by me is definitely not accurate - which I hope most readers here realize. There is not even any uncertainity in the projection.

This is just to show that Arctic temperatures are probably far from equilibrium with current CO2, not to mention further rise.

I hope that explanation helps a little,

Alex

John Christensen

Nevin,
Thanks - great to share this video and great research!

It was interesting to see that prior warmth periods appear to relate less closely with CO2 level (MIS 31, 1.1mio years ago was 6-7 degrees warmer than now with CO2 at 300ppm), that extreme warmth was more frequent in interglacial periods than expected, but more alarmingly (though possibly less surprising) that ice sheets are much more adaptive than anticipated and will react, as temperature moves up or down.

John Christensen

Note: My comment only refers to the video presentation of the research, as I have not been through the article.

Climate Changes

Correct me if I'm wrong but doesn't Ms Grette call a figure of around 300+ppm and not 400ppm?

SATire

Hello.
We just had a long discussion about that Brigham-Grette paper at German www.zeit.de some days ago.
Main critics was that in the paper they do not refer to the closing between south and north america (at Panama) during that time, which had quite an effect ocean currents and on global clima.
http://geology.gsapubs.org/content/37/10/959.full

So the paper is again not a clear signature, that the higher CO2 did cause the higher temperature. Things stay complicated - especially during the pliocene-pleistozene transition.

Ac A

SATire,

hopefully you are right - nobody was around in Pliocene or Pelistocene. But we also know that sea level was 20m (+/-5m) higher than today, so NO ice in the Arctic (and much less in Greenland or Antarctica).

The thing is the researchers expected higher temperatures, but not THAT high tempratures. And climate models have prolems explaining such conditions. That's why that talk of (probably) higher climate sensitivity.

The paper was also no "attribution" study.

SATire

Ac A,
exactly. Talking "(probably) higher climate sensitivity" (of CO2 content) while ignoring the permanent "El Nino" those days sounds like mainstream propaganda and "usual brain washing" to many readers paying the CO2-reduction bill today, since newspaper write such things every few weeks.

The point is, that the link between higher temperature and higher CO2 content is not made clear by the paper but mentioned "hand waving". It was warmer those days, but probably also due to different ocean currents and not only CO2.

D

Correct me if I'm wrong but doesn't Ms Grette call a figure of around 300+ppm and not 400ppm?


====

Yes, she did. It was even written on one of the slides.

We passed 300PPM about 50 or 60 years ago, so nobody go blaming AGW on people half that age.

The sensible conclusion is that there is an error either in the data or in the presentation.

SATire

in the paper it was 400 ppm

John Christensen

Ms Grette specifically commented in the presentation that the warming in MIS 31 was attributed to orbital forcing..

Neven

Didn't the closing of the Panama Isthmus cause cooling (not immediately, but on the whole)?

SATire

right Neven. So before that it was warmer.

SATire

but _maybe_ the closing caused the cooling just by reducing CO2. And maybe not. That is the puzzle one should adress.

Erimaassa.blogspot.com

right Neven, the shallow strait in southern Panama is thought to have let the el Nino warmth to Atlantic and then north, or that's how I have understood it. Anyway Pacific gathers more heat than Atlantic even nowadays, or so I've understood the role of AMOC.

Boa05att

The isthmus was thought to have formed ~ 3 million years ago.

She's talking about super interglacials at MIS 11 and 31 (approx 400 ka and 1050 ka)

i.e. way after the ismuths had closed.


Bluesky also linked to a longer talk given by Prof. Brigham-Grette which I'd thought I'd link to here as well as it goes into more detail.

http://www.youtube.com/watch?v=MDWUzWAtiyQ

Climate Changes

"The sensible conclusion is that there is an error either in the data or in the presentation."

Perhaps that is the case :\. If CO2 levels were 300-328ppm in the super-interglacials as shown on the presentation, this would mean that at 400ppm -and growing- we are pretty much guaranteed 8C+ as soon as the Earth's systems catch up. Equally, it would mean that CH4 is highly likely to be realeased in big amounts.

Neven, many congrats on your 500th. Your blog keeps my sanity in a world of denial:)

SATire

oh sorry - I was not talking about the presentation but the linked science paper. That is dealing about pliocene warm climate, when CO2 was 400 ppm and the Panama Isthmus just about to close.
For the interglacials there are orbital reasons.

The point is - there is no "proof" for a high CO2 sensitivity (and can not be given by science), only hints with a lot of issues to argue about. One should make the issues clear to prevent the appearance that one would be biased by opinion or even to be "brain-washed". There are a lot of cute poeple out there wich could easily be turned to become "denialist" by obviously biased statements.

Aaron Lewis

Re text at end of calving video:

Nobody alive has witnessed a calving event in a period of global cooling, and ice/climate models do not calculate ice dynamics at that resolution, thus they do not know if the calving event is, or is not evidence of global warming.

Thermodynamics tells us that with global warming, the ice heat content of the ice is greater, and material science tells us that ice containing more heat is weaker. When stressed, cracks propagate through the (warmer) ice leaving films of water that allow additional movement and focus stress, facilitating additional cracking. In warmer ice, the water in stress cracks does not refreeze to heal the cracks. Therefore we know, the calving event was affected by global warming.

In a period of global cooling the ice would lose heat and become stronger. When over stressed, cracks in the ice would propagate and then refreeze after the stress was released. Draw your own conclusion as to whether the calving event was evidence of global warming.

In engineering terms, the calving event was progressive structural collapse. Progressive structural collapse of ice sheets can occur on land also. All that is required is warm, weak ice at the bottom of a heavy ice structure.


Chris Reynolds

Steve,

That paper on Arctic Amplification in the Pleiocene looks very interesting. I've asked HeisenIceBerg if s/he can get a copy.

SATire,

Thanks for the words of explanation and caution.

Steve Bloom

To repeat the point for those above who missed it, the video is discussing a paper prior to the one that was just published.

SATire, the key point missing in that discussion is that global/polar temps *increased* from the Zanclean through the mid-Piacenzean even while the Central American and Indonesian seaways were completing their process of closure. Note that the deep currents would disappear earlier than complete closure. The mid-Piacenzian warming is basically not explainable by anything other than CO2, as demonstrated IIRC by several recent modeling studies. There's been a huge amount of other recent progress in the study of the detailed causes of Pliocene warming, which I suggest you catch up with. I'll save you some time by pointing to Hansen's latest.

Note also that even the material you linked to claims a climatic effect of seaway changes primarily by way of affecting atmospheric CO2 levels, rather than a more direct mechanism. The introduction to Etourneau et al. (2009) makes this point unambiguously.

Neven, all of this confusion makes me think you should clarify the foregoing in the post and put a label on that second graphic. You've done a great job so far, but I'm afraid it takes eternal vigilance to keep this blog from dissolving into amateur hour.

Alex, just to be clear on this point, the major difficulty with the second graphic isn't so much the 2100 date (although that is a problem, even presented notionally), but that you're comparing Arctic-wide apples with the relatively cool Lake E orange. Ultimately we would expect ~400 ppm at equilibrium to get us to more like +~18C in the high Arctic (based on recent results from northern Ellesmere, note immediately adjacent to the sea ice "refugium" and the GIS).

BTW, I need to now take the time to re-read everything more carefully myself since all of this material doesn't sink in all that well on a first pass, but my impression is that the key novel finding of the new paper is not that the Arctic was very warm (we've known that for years) but that the Lake E record shows relatively (and surprisingly) little effect from Milankovitch cycles (as opposed to more recent times, e.g. MIS 11 and 31 as discussed in the video). The important implication is that the CO2 is very dominant indeed, and that NH Arctic ice (all of it) and the WAIS simply disappear at current CO2 levels. Oops.

Neven

Thanks, Steve. I've updated the post and linked to your and Alex's comments.

SATire

Steve,
thank you, your hint makes me feel a bit better. But I still suffer a bit my shock: After reading that paper I felt that pliocene clima would be the clima corresponding to current CO2 level as I thought before and I did not miss anything. But it was missing the discussion of the changing ocean current at about that time. In my professional live that would have been a fatal fail without possible excuse - sceptics is the basis of science. Slowly realizing this during a long discussion made me feel like beeing biased or even brain washed due to following discussions mainly with poeple with similar kind of thinking. That is a bad risk getting significant when discussing with poeple, who just changed there opinion due to such a discovery of beeing biased and loosing ground to sceptical observations. That can turn poeple to denialists for a good reason.

I am not through with that pliocene puzzle yet - it need a lot more of puzzling effort and I have to read your links and some more.

So - lets take care of our scepticism. Especially if we think we are right we surely aren't anymore.

Steve Bloom

Hi Chris (and SATire), also worth looking at in this regard:

Poulsen, C., and J. Zhou, 2013: Sensitivity of Arctic Climate Variability to Mean
State: Insights from the Cretaceous. J. Climate. doi:10.1175/JCLI-D-12-00825.1

A. V. Fedorov, C. M. Brierley, K. T. Lawrence, Z. Liu, P. S. Dekens and A. C. Ravelo, 2013: Patterns and mechanisms of early Pliocene warmth. Nature. doi:10.1038/nature12003

Thanks so much for the corrections, Neven.


Steve Bloom

SATire, have you read the paper? The material you seem to think is missing is thoroughly referenced. It's not *discussed* to speak of, but then it would be surprising for it to be given that the paper has a different focus.

A vast amount of research has come before, as is obvious from the paper's extensive (>100) references. You might consider reading up on PRISM and PlioMIP in general.

Anyway, it looks to me as if you may have run into some people who mainly wanted an argument. If that wasn't the case, it seems like they would have noticed that the science points strongly away from tectonically-driven circulation changes as a major cause for the cooling, and toward reduced CO2 as the primary cause of the circulation changes.

Steve Bloom

Aha, I see you did say you had read the paper. Sorry for missing that.

In that case note the last sentence on page 2:

In sum, model sensitivity to Pliocene boundary conditions including atmospheric CO2, appears to be slightly lower than the observed sensitivity at Lake El’gygytgyn.

Those boundary conditions include tectonic differences. FYI, co-author Robert DeConto is a leading paleo-modeler.

Steve Bloom

Neven, a comment I made an hour or so back has yet to appear, even though the others passed through. But given the history, two out of three ain't bad! :)

Steve Bloom

Well, two out of four (or possibly five, depending on what happens with this one).

Ac A

Steve,

thanks for valuable comments! I hope it will spurr further discussion, but the basic line is clear, I hope.

Cheers,

Alex

Robertscribbler.wordpress.com

What's becoming more and more clear is the fact that CO2 levels and increasingly high quality paleoclimate data are far better proxies for what is likely to happen to the Arctic than current climate models. Further, if what's happening to the Arctic now is, as this paper suggests, due to the CO2 levels experienced 20-30 years ago (approx 350 ppm), then the blow to the Arctic in the coming decades is going to be extraordinary (I understood this rationally before, but, for some reason, it took this paper to drive the message home).

@SATIRE

Skepticism is an activity in which one weighs the most likely outcomes against the best facts available. This is healthy. And it appears to me you'd do well to research those facts a bit more. PRISM, Hansen's recent Pliocene-related work, and PlioMIP, as Mr. Bloom above suggests would all be a good start.

Steve Bloom

A little more on this subject:

In a disappeared comment above (likely it will appear when this one does) I cited Fedorov et al. (2013), regarding which I just noticed a public copy. On re-reading it just now I see the following passage:

Enhanced ocean poleward heat transport during the Pliocene has been proposed as another factor that contributes to keeping high latitudes warm, especially in the northern Atlantic. However, climate models calculate changes in ocean heat transport interactively and so require particular forcing mechanisms, such as an open Central American seaway (CAS). Originally, the CAS closure was discussed in the context of the onset of glaciation around 2.7 Myr ago, but the closure is now estimated to have occurred between 4.7 and 4.2 Myr ago, as inferred from the divergence of planktonic d18O between the Caribbean Sea and the Pacific. Recently, it has been suggested that the seaway closure, and the resulting intensification of deep-ocean circulation due to increased salinity in the Atlantic, could have led to a shoaling of the thermocline in the Pacific, facilitating the subsequent cooling.

Opening the CAS in our model to a depth of 150 m (ref. 5) causes a reduction in the strength of the Atlantic meridional overturning circulation, a cooling of the Northern Hemisphere and a warming of the Southern Hemisphere (Fig. 5c, h and Supplementary Fig. 11). However, impacts on the equatorial SSTs are minor. The equatorial thermocline deepens a little in the central Pacific but shoals in the very east. Opening the CAS to the largest possible depth (1,100 m) barely changes the zonal SST gradient along the Equator, but amplifies the interhemispheric seesaw pattern with a strong cooling in the northern high latitudes (Supplementary Fig. 11), contradicting the observations. Similar behaviour is seen in other models (ref. 41; Supplementary Fig. 12). Another tectonic factor potentially important for Pliocene climate is the northward drift of New Guinea, which may have altered the source of waters entering the Indonesian throughflow and feeding the Equatorial undercurrent and upwelling. However, in agreement with previous modelling studies, our results show impacts barely above statistical significance (Fig. 5b, g) and do not explain the Pliocene climate state.

That seems definitive, leaving reduced CO2 as the primary driver of the circulation changes (although the latter do seem to have acted as a positive feedback, helping to reduce CO2 even more).

Neven

Sorry, Steve, seems the spam filter has fallen in love with you again. I've been discussing this on and of with TypePad. Tried nice, by helping and reporting all the stuff that goes wrong for a couple of days. I've tried the less patient route as well, but basically there's still not much I can do (except switch blog host after the melting season). Hopefully they get this solved, soon.

Steve Bloom

Of course, Alex, entirely clear. It's just that when we depart from the science we should be clear that we're doing so.

I understand entirely, Neven, although I'm afraid the spam filter's deep feelings will have to remain unrequited.

SATire, I don't want it to seem like that was piling on. What happened to you was a standard fake-skeptic debating trick, and most of us will have fallen for some variation on it when we were new to this stuff, so we all sympathize.

My suggestion to you would be to turn the tables on them next time, asking them how they know that some random paper from a few years back is actually representative of the science on the point. Of course you can, if you like, check the paper's citations on Google Scholar (here for this one, filter for results in the last two years and then see how things really are. But be aware when you do it that they won't bother to do any such thing themselves and will just try to change the subject in response.

Oh, and anyone who tells you that they were all happy with the consensus up until they found out that that horrible Julie Brigham-Grette and her many co-authors are misleading the public on a point so obvious that someone who knows almost nothing about the science can spot it, and so now it's Julie et al.'s fault that s/he has decided that the denialists have more credibility? S/he is lying.

Summing up, it's inadvisable to take at face value any representation they make about the science. Be prepared to do your own homework. If necessary, by all means come here or a similar place to get some guidance. Good luck out there!

Kevin McKinney

OT, but for those interested, I've got a brief article on reaching 400:

http://doc-snow.hubpages.com/hub/400-Now-A-Climate-Change-Milestone

I may possibly have a fresh take on it... maybe.

Bfraser

At the risk of getting more egg on my face, I'd like to point out two minor typos in Kevin McKinney's otherwise excellent paper:

One, You typed "namy" instead of "many".

Two, Each water molecule has only one oxygen atom, not two.

Kevin McKinney

D'oh--I knew that! (Well, not the typo...)

Thank you, sir.

Kevin McKinney

...better now...

Shared Humanity

Kevin.....

Superb article!

SATire

Steve,

"What happened to you was a standard fake-skeptic debating trick"

If it was a trick, it was that the other person was concerned. And so was I.
Other poeple might argue, that simulation results are a trick, to get another 500€/person/year for nothing instead of something useful. But in the end, if you try to understand each other, you can find a common basis of understanding and also differences in conclusions or priorities. That is worth the discussion. Using tricks or imputing tricks to the discussion partner would not help you to understand. Do not see the enemy in your partner because that makes you his enemy.

Therefore, it is very important to be clear, careful and understandable if one talks about amplification. In the end it is talking about priorities and where to spend the extra-money. Poeple need to understand that exactly and not with by hand-waving arguments like in the science paper. (btw - I am not an expert here and I have no idea which citation includes what, since I did not read all literature given in the paper.)

Steve Bloom

"hand-waving arguments like in the science paper"

I just spent a chunk of my valuable (to me) time pointing out why that statement is incorrect. What happened is that you fell for a hand-waving argument in that on-line discussion.

You are ignorant, but it's something you could fix with a little work. Give it a try.

Ac A

OT, but related to "global warming stopped" propaganda. William Happer wants 1000 ppm CO2, good for plants...:

http://www.bishop-hill.net/blog/2013/5/17/happer-on-cnbc.html

Alex

SATire

I am sorry that I have wasted your time. As I mentioned allready above - I will read the papers and try to dig into that pliocene puzzle. I think you have strange view on that discussion I had elswhere - that is because I only stressed the one point which was important for me personally. That discussion was good but the experience of my ignorance was hard for me, as I tried to explain above. But now you got that impression independently.

GeoffBeacon

Neven, 500 congratulations for your brilliant blog(http://neven1.typepad.com/blog/ - for those reading this on twitter)

Kevin McKinney

Shared Humanity, thanks! Appreciate that.

k eotw

In June and July when insolation is high in the Arctic the difference between ice free and ice covered ocean would be chalk and cheese.

Not only would the oceans be absorbing a hell of a lot more sunlight if open, but there would be no ice with it's absurdly high latent heat to buffer against temperature increase.

It's like the ice is the Arctic's suncream which it puts on in winter.

That seems to worryingly explain the drastic difference between cooler arctic (recently) vs much warmer arctic (paleo).

Of course it explains nothing really as I am just guessing, but it does seem to fit. Then again I sure the climate models are better than my guesses.

Kevin McKinney

Hey, check out the weather underground story in the sidebar--looks like a new impact of sea ice area loss.

Jai Mitchell

This is only further indication that the climate sensitivity analysis from the paleo data is skewed by the glacial maximum dataponts. That the "anomalously high" data that is being thrown out in the studies all happens to occur during the interglacials when the polar sea ice melts. As much as we might not like it, we should be prepared for real discussion regarding a long-term climate sensitivity of 8C+/-2.5 during this CO2 driving, interglacial cycle. This is especially true when one considers that CO2 and Methane were held relatively constant during the Eemian Maximum due to terrestrial and oceanic flora responses to a gradually warming environment.

Jai Mitchell

A Ca,

Happer of the Marshall Institute happily states that we would be just fine in a 5000 ppm environment since the Eocene thermal maximum, since small mammals thrived during this period. He is paid well to hold seminars where he educates lawmakers on the non-importance of global warming.

Neven

Thanks, Geoff and others, for the congrats.

k eotw

I wonder if Happer would really press a 1000ppm button if it was in front of him. I suspect faced with the reality of the choice he wouldn't.

Apocalypse4Real

OT but important.

Canada has just funded continued operation of the Eureka climate station for five years. It was supposed to go off line.


High Arctic research station saved by new funding

Eureka's PEARL gets $5M over 5 years

http://www.cbc.ca/news/technology/story/2013/05/17/technology-pearl-high-arctic-research-station-funding.html


Bill Fothergill

@ Neven and 500

Happy anniversary. Don't stand too close to the candles. (Or even the Crandles.)

Just randomly playing with numbers here, but if you were to light up 500 of those biggish 4 ounce candles, it would release enough energy (circa 500 megajoules) to melt about 1.5 - 1.75 cubic metres of ice.

So behave yourself - think of the effect on the albedo.
(Having had a beer or two, I take no responsibility for the accuracy of the above numbers.)

@ Kevin and 400.

Nice article. Apologies if this has been mentioned earlier, but the big 400ppm was passed at Point Barrow in March last year.
Please see the announcement...
http://researchmatters.noaa.gov/news/Pages/arcticCO2.aspx

The Earth Systems Research Laboratory run by NOAA has a neat animation showing the seasonal CO2 ramp up from 2000. (the year, not the concentration)
http://www.esrl.noaa.gov/gmd/ccgg/globalview/co2/co2_intro.html

The Scripps institute also has an interesting graphic comparing the readings from 6 different stations.
http://scrippsco2.ucsd.edu/graphics_gallery/other_stations/global_stations_co2_concentration_trends.html

This of course merely confirms that the volcanic CO2 emissions from Mauna Lau are simply being bottled and transported to these other monitoring stations as part of the conspiracy to impose a one world government under the auspices of the United Nations.


Back to the beer billthefrog

Ac A

Apocalypse,

yes, and canadian government also doubled the amount of money for tar sands:

http://www.guardian.co.uk/environment/2013/may/16/canadian-government-doubles-advertising-spend-tar-sands

k eotw,

I dont think so - climate deniers are too crazy...

Alex

bluesky

... and Dr James Hansen is here in Europe to campaign against tar sands, and he had to explain again to the BBC about recent raising temperature, got the feeling that the BBC is playing the fake sceptic agenda and hasn't done its homework again on climate change... may be we should write " en masse" to the BBC...
http://climatecrocks.com/2013/05/18/i-should-correct-what-you-just-said-hansen-on-global-surface-temps/
James Hansen also gave an excellent lecture at the LSE on Thursday, he advocates that we should sue our governements to court to take them accountable about their lack of policy and action for reducing GHG emission to avoid dramatic climate change

bluesky

again this BBC insistance on the supposedly slow down of warming and additionally drowning the real facts (and ignoring most of them like that the Pinatubo eruption in 1991 and the record el Nino in 1998 which give a much more steep apparent curve in the 90ies compared to the the 2000s, together with ignoring the cooling impact of aerosol and drowning the 90% absorption of heat by the ocean while forgetting to mention that there was far less El nino impact in the 2000s than in the 1990s) giving the voice twice to a prominent sceptic in the following program... this subtle play is suspicious:
http://www.bbc.co.uk/news/science-environment-22565278

P-maker

“The sky is red tonight
We’re on the edge tonight
No shooting star to guide us

Eye for an eye, why tear each other apart?
Please tell me why, why do we make it so hard?
Look at us now, we only got ourselves to blame
It’s such a shame..”

http://4lyrics.eu/esc/2013/emmelie-de-forest-only-teardrops/

Winner of Eurovision Song contest this evening

Chris Reynolds

Thanks for digging into the Fedorov paper, and making things more clear.

I've just had the chance to give that paper a once over. I am now satisfied that CO2 was most likely the driver of the Pliocene warmth. It also ties in well with the Ballantyne paper that you recently linked to.

"The amplification of Arctic terrestrial surface temperatures by reduced sea-ice extent during the Pliocene." Ballantyne et al 2013 (I've asked HeisenIceBerg to get a copy of that if poss)

Which ties in with the current mechanisms of Arctic Amplification.
http://dosbat.blogspot.co.uk/2013/04/the-causes-of-arctic-amplification.html

And is yet another period which gets me wondering about the equable climates issue during the late Paleocene, and what will happen when we start having seasonally sea ice free summers in the Arctic.

Are you being driven by new research (such as that mentioned by the lead article), or are you actively looking into 'equable climates'?

Chris Reynolds

Steve Bloom,

Above comment is meant for you (when it's released from the spam folder).

P-maker

”In the summer night, when the moon shines bright
feeling love forever.
And the heat is on, when the daylight's gone
still - happy together...”

http://www.youtube.com/watch?v=Du1QG6Tkn2A

Winner of the Eurovison Song Contest in Stockhom 2000 – Ah! Those were the days of the good old geezers…

(please enjoy the British commentary after 7:30 in this video: http://www.youtube.com/watch?v=4oqsGA53BlQ ).

I believe Sir Terry has been working with the BBC for well over 40 years, which explains quite a lot in my opinion.


bluesky

A new paper from Polyak et al on Western arctic sea ice extent:
"results suggest that year-round ice in the western Arctic was a norm for the last several 100 ka, in contrast to rapidly disappearing summer ice today".

"Quaternary history of sea ice in the western Arctic Ocean based on foraminifera"
Leonid Polyak et al.
http://www.geotop.ca/upload/files/publications/chercheur/St-OngeG/Polyak_2013.pdf

George Phillies

Readers who examine the Point Barrow view camera
http://feeder.gina.alaska.edu/webcam-uaf-barrow-seaice-images/current/image

will note that the ocean is still frozen solid -- at least, I am fairly sure that is ice, not big waves -- but if you look at the lower left of the photo you may be able to spot the melt pond with shallow liquid water in it. That's at least somewhat warm.

Boa05att

The amplification of Arctic terrestrial surface temperatures by reduced sea-ice extent during the Pliocene

Abstract

Many past warm periods exhibited greatly reduced latitudinal temperature gradients as a result of amplified Arctic surface temperatures as well as more seasonably equable temperatures. The Pliocene is a period of particular interest because CO2 forcing was comparable to today and yet Arctic temperatures were significantly warmer than today. Here we describe an atmospheric general circulation model experiment assessing the response of terrestrial temperatures in the mid-Pliocene (3.02 to 3.26 Ma) to an ice-free Arctic, and we compare the simulation with a compilation of proxy-based Pliocene paleotemperature reconstructions. Our experiments indicate that the amplification of Arctic surface temperatures is much more sensitive to the extent of sea ice than continental ice. The removal of Arctic sea ice results in simulated mean annual surface temperatures that better match terrestrial proxy data (RMSE = 2.9 °C) than experimental conditions that included seasonal sea ice (RMSE = 4.5 °C). Our simulations also show a decrease in the seasonal amplitude of temperatures in the absence of sea-ice, which is consistent with theory predicting more equable climates in the Arctic during warmer intervals in Earth's history. Our results demonstrate that once sea-ice is removed, latent heat is lost from the ocean to the atmosphere as water vapor that can be circulated by the atmosphere, which results in warming of continental interiors. Although our sensitivity experiment does not help to identify the full array of feedback mechanisms responsible for the amplification of Arctic surface temperatures during the Pliocene, it does demonstrate that Arctic terrestrial surface temperatures are extremely sensitive to the spatial and seasonal extent of sea-ice.

http://www.sciencedirect.com/science/article/pii/S0031018213002265

Press release:
Arctic Sea Ice During the Pliocene Era
http://www.sciencedaily.com/releases/2013/07/130710104650.htm

Wayne Kernochan

A quick comment on some of the subtext in the above comments: as I understand it from www.climateprogress.com and comments from Dr. James Hansen, we are uniquely fast in how we are moving from 250 ppm at the start of the Industrial Revolution to 400 ppm now to 500 ppm and beyond in the future. As a result, ancillary non-CO2 warming mechanisms are occurring now and not being counteracted by later cooling mechanisms like weathering. This in turn heightens the heating effect for today's rise beyond what the CO2 itself would cause.

In other words, a doubling of CO2 would by itself cause 2-3 degrees C of warming; the unique "knock-on" effects occurring now may add 1-2 degrees C to that. (There are also counteracting aerosol-pollutant rise effects as of now that will likely cease in the next 30 years, as otherwise we will start dying in serious numbers from that pollutant). Back then, it may have been a matter of our underestimating climate sensitivity to CO2, although I lean against that; today, I think it's less a matter of climate sensitivity to CO2 and more a matter of these ancillary effects.

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