Continuation of the open thread. Please use these threads to bring up things that are creating ‘buzz’ rather than having news items get buried in comment threads on more specific topics. We’ll promote the best responses to the head post.
Knorr (2009): Case in point, Knorr (GRL, 2009) is a study about how much of the human emissions are staying the atmosphere (around 40%) and whether that is detectably changing over time. It does not undermine the fact that CO2 is rising. The confusion in the denialosphere is based on a misunderstanding between ‘airborne fraction of CO2 emissions’ (not changing very much) and ‘CO2 fraction in the air’ (changing very rapidly), led in no small part by a misleading headline (subsequently fixed) on the ScienceDaily news item Update: MT/AH point out the headline came from an AGU press release (Sigh…). SkepticalScience has a good discussion of the details including some other recent work by Le Quéré and colleagues.
Update: Some comments on the John Coleman/KUSI/Joe D’Aleo/E. M. Smith accusations about the temperature records. Their claim is apparently that coastal station absolute temperatures are being used to estimate the current absolute temperatures in mountain regions and that the anomalies there are warm because the coast is warmer than the mountain. This is simply wrong. What is actually done is that temperature anomalies are calculated locally from local baselines, and these anomalies can be interpolated over quite large distances. This is perfectly fine and checkable by looking at the pairwise correlations at the monthly stations between different stations (London-Paris or New York-Cleveland or LA-San Francisco). The second thread in their ‘accusation’ is that the agencies are deleting records, but this just underscores their lack of understanding of where the GHCN data set actually comes from. This is thoroughly discussed in Peterson and Vose (1997) which indicates where the data came from and which data streams give real time updates. The principle one is the CLIMAT updates of monthly mean temperature via the WMO network of reports. These are distributed by the Nat. Met. Services who have decided which stations they choose to produce monthly mean data for (and how it is calculated) and is absolutely nothing to do with NCDC or NASA.
Further Update: NCDC has a good description of their procedures now available, and Zeke Hausfather has a very good explanation of the real issues on the Yale Forum.
Tim Jones says ““Tim jones hasn’t read many of the posts here when he states: “branch out from preaching to the choir”.”
Now how would you be knowing that?”
Because there is most DEFINITELY NOT “the choir” here.
1) Many posts flat out state that Gavin et al are part of a global conspiracy in order to bring in the bennies.
2) This is the internet. Plenty of people on other newsgroups state just what #1 do
So in so far as the recipients of the word, the choir includes everyone. The only way to avoid preaching to everyone is to shut up.
Is that what you’re demanding?
If I state that 2×2 = 4 is that preaching to the choir because so many people would agree that’s true?
This is what you seem to think, based on how you consider this site to operate.
“My response was to document the vast difference between toxic (50,000 ppm) and the current atmospheric levels (over 380 ppm) ”
Toxic effects occur at 1000ppm. Heck, there’s reduced operation of human organisms below 700ppm.
You just don’t drop dead immediately unless it’s thousands of ppm.
Fail.
Jimi Bostock what hemispheric cold? From http://www.esrl.noaa.gov/psd/map/images/rnl/sfctmpmer_07a.rnl.html
it looks like rather the planet is sending more of the Canadian and Arctic Ocean cold down than usual. The reason for That is of interest to me too, could be climate, could be weather, if I would be asked (and trusted on this matter, and luckily there are forums in the net to opinionate :-)).
PS the problem with “CO2 is more dense and sinks to the ground” is that the air doesn’t stratify out like that.
400/1,000,000 x 11km makes 4.4m of CO2.
If the air distilled like that, we’d all suffocate.
PS tim, what would you say to this site:
http://blackswhitewash.com
made up expressly to vilify a reporter because he doesn’t report what they want to hold up as the truth.
Dave Bassage, the topic of how we know that CO2 is well mixed in the atmosphere has been discussed in the comments sections in two threads at Skeptical Science the past couple days, starting with a question by Theo on one thread with augmentation on another thread.
First of all just want to clarify that I am not to be confused with any other ‘Matthew’ here – it is just a rather common first name!
I am gradually getting a handle on this debate and am beginning to form a (hopefully) rational view of my own.
After reading a lot of stuff here, and elsewhere, it is clear that
– the globe is warming
– that warming is having adverse effects on our environment – particularly the cryosphere
– human CO2 emissions are probably (i.e. more likely than not) a major contributor to that warming.
The current state of climate science and modelling shows that the climate is sensitive to increased levels of CO2 with a positive feedback balance. Scientists are right to point out the overwhelming weight of evidence to date for AGW.
However I think they miss a major point in that in a ‘predictive’ science such as climate modelling (or economics) just because the knowledge acquired to date all tends towards one conclusion does not necessarily make that conclusion correct. In fact, in something as hugely complex as climate science, it is probably reasonable to assume that there are many things we simply do not know and have not even thought of yet – one or more of which may be a real ‘biggie’.
Already we are aware of some ‘known unknowns’ such as the sign of cloud feedback and the effect of cosmic rays. The problem for climate science is that these are both potential ‘biggies’ against current predictions. Water vapour is the strongest greenhouse gas but low level cloud has a big negative (albedo related) effect. Current models assume relative humidity is stable as temperatures increase but empirical evidence is showing it reduces. Why? Could it be that humidity is reducing because more condensation (cloud) is being generated than predicted? More cloud would mean a higher albedo effect than predicted. Reduced relative humidity means there is less water vapour than predicted in the atmosphere as temperatures rise. Both more cloud and reduced water vapour reduce the positive feedback effect from CO2 rise and may even send it negative.
CERN is currently doing tests on the effect of cosmic rays which may point to a role in cloud formation which might explain some of the recent warming (during higher solar activity) and may lead to a reduced positive feedback balance.
Until climate science has pinned down at least these major issues is it really safe to hitch our entire economic and political system to an attempt to reduce CO2?
In addition there are likely to be a lot of ‘unknown unknowns’. And I would suggest it would be rather rash for any scientist to pin his/her reputation on the current state of knowledge being correct with 90% certainty.
As well as some concerns over the current perception of climate science, I also think the whole international attempt to reduce CO2 emissions is doomed to failure. Whatever we do, short of a war, we are not going to be able to stop China and India and their neighbours growing fast and increasing their CO2 outputs far faster than we can reduce output. Their undertaking to reduce ‘energy density’ is laughable. We can only cross our fingers and hope that China at some point gets the message and decides to co-operate. We don’t have international Government, and until we do, our best strategy would be to try and mitigate the effects of climate change (as well as sensible fossil fuel reduction policies of our own of course).
Being an older guy I have seen many environmental and energy crises come and go I am naturally sceptical of political bandwagons hitched to the back of scientific arguments. The politicians have a lot of whips and carrots they can use to send the scientists where they want them to go – please don’t be led!
Politicians and Kings like consensus, they don’t like sceptics and ‘turbulent priests’. The problem is that the ratio of village idiots to turbulent priests (true sceptical scientists) at the moment probably runs at a ratio of about 100,000:1 or greater – and it is all too easy to tar the latter with the same brush as the former.
My final point (you will be glad to read!) is the fact that all the hullabaloo over CO2 is diverting our attention from some real environmental disasters happening now with absolute 100% certainty that we can actually do something about without changing the entire world economic system:
– deforestation and all the myriad disasters that causes (landslips, water run-off, species extinction, bio-diversity destruction etc)
– over-intensive agriculture on marginal land causing desertification
– water over-extraction, dry rivers, ground water salination, water wars
– over-population and poverty
– fisheries destruction
– big game poaching
…to name but a few.
I know the latter point is not really what this site is about, but does anybody in the Real Climate community share any or all of these concerns?
#243 Proper Ganda
How about Google Scholar? It has some anti-bodies against memetic infections.
It also sometimes finds articles in Realclimate.
Occasionally useful is to create a filter by adding the words “Google Scholar” to a search string in Google.
But seriously you highlight a major problem. The internet is a major amplifier of garbage and it can be bought by the richest bidders.
However it is not only the internet. I have been into the local bookshop and seen piles of the latest denialist books as against only one or so of the more serious science. I even asked for a book which had been well reviewed here, and was told that the bookshop had no plans to hold it. I then went to look for more reviews and found that it had also been well reviewed on the central web site for that chain of bookshops. Another phone call , no change of policy. Then there is the UK press; the Daily Express has recently carried an article entitled 200 things wrong with the science of global warming (or similar); they can now been added to the Mail and Telegraphs.
I notice that you take the opposite position from that of #225, but because of the internet and other examples such as the above, I tend to veer more towards your view. It matters a lot what the general public thinks.
The rise in atmospheric CO2 is so slow and the human organism’s biochemistry is so very adaptable, we have nothing to fear on the respiratory front. Climatic effects may be another thing……….
Matthew L. says, “And I would suggest it would be rather rash for any scientist to pin his/her reputation on the current state of knowledge being correct with 90% certainty.”
And I would suggest that you understanding of the current state of knowledge is very incomplete. Yes, clouds remain a big uncertainty. So do aerosols. However, we know with a high degree of confidence that CO2 sensitivity is between 2.1 and 4.5 degrees per doubling, with a most likely value of 3 degrees per doubling. That is constrained by over 10 independent lines of evidence–all of which favor a value around 3 degrees per doubling. What is more, if the most likely value is wrong, it is most likely to be too low rather than too high.
We also know that the current warming epoch looks just like what we would expect from a greenhouse mechanism–including tropospheric warming and stratospheric cooling.
The greenhouse effect has been known since 1824. That anthropogenic greenhouse gasses ought to warm the globe was predicted in 1896.
And on and on. In short, climate science is actually a mature science, with a theory of Earth’s climate that has a long list of successful predictions to its credit as well as very strong explanatory capability. In contrast, your suggested alternative of GCR modulation of clouds is flawed for several reasons–GCR fluxes did not increase after 1950 to the present (modula solar-cycle variations), the mechanism for GCR resulting in cloud-condensation nuclei is murky at best, and it is not clear that there is ever a shortage of CCN in any case. Most important though, such a mechanism would not negate what we already know about the role of CO2 in Earth’s climate, which is constrained by mountains of paleoclimate and current data.
Finally, your casual dismissal of scientific consensus demonstrates a deep ignorance of how science actually works. Consensus does not concern opinions of individuals as it does utility of ideas, techniques and theories. When an idea, technique or theory becomes so indispensible to understanding the world that nearly all authors use or assume it in their work, we have consensus. By any measure, the importance of CO2 and other greenhouse gasses has achieved such a position. The power of consensus is demonstrated not just by the many papers published that support the consensus, but also by the dearth of publications (especially influential ones) from those few scientists who dissent from the consensus.
Science works. Deal with it.
Jimi@244
Your concern with style is noted. Got any substance?
And yet your post is remarkably free of evidence.
Come on. Admit it. You didn’t come here to learn what scientists think. If you were paying attention, you’d know that what you said just isn’t true. You came here to give them uppity egg-head scientificals what for. Either that or you’re a POE.
Some. Not so much in this forum. Except for people who say things like “You babble and vitrioul is boring.” Oh wait. That was you.
This has been discussed over and over and over and over and over and over and over and over and over and over and over and over and over and over and over and over and over and over and over and over and over…
Climate isn’t weather. And do you wonder that people get angry with you?
> we have nothing to fear
“What did you mean “we” grandfather? Wheeze …..”
Look this stuff up before you make statements that resemble facts, and you’ll get more accurate over time. Yes, if you have no descendants, the narrowly construed “we” that means “you” has nothing to fear.
Indoor CO2 levels in any sizeable occupied building are always markedly higher than outdoor CO2 levels.
http://www.google.com/search?q=co2+levels+indoor+outdoor
See the problem?
Got grandchildren?
Bill, wrong.
How long will it take for the physiological problems to be abated by a genetic change in human respiration? a few thousand generations?
If we burned all the coal and oil and captured the methane to burn too, what PPM would we have? How long would that take?
Current estimates would have 400 years to reach 1000ppm where we have physiological problems.
less than a hundred generations.
Jimi,
The reason I didn’t come out and say that the global temperature for November 2009 proves climate change is happening is because one months numbers don’t prove anything. November 2009 is the warmest November in the global instrumental record series see here: http://data.giss.nasa.gov/gistemp/graphs/.
Or how about the data for the Central England Temperature, the longest instrumental time series there is. From 1659 to present day. If the ranking is 1 for the coldest month or year, and 352 is the warmest. Then December 2009 is ranked as 99 and November 2009 is ranked as 345. This doesn’t prove anything either. It is short term temporal noise in the climate system just like having December 2009 being quite cold. See here: http://hadobs.metoffice.com/hadcet/data/download.html
But if you want interesting information in relation to the number of records broken, hot or cold then see http://scienceblogs.com/islandofdoubt/2009/11/record_high_and_low_temps_an_i.php for information about the US.
Kevin
Matthew L. wrote: “… all the hullabaloo over CO2 is diverting our attention from some real environmental disasters happening now …”
Global warming and consequent climate change driven by anthropogenic CO2 emissions is a “real environmental disaster happening now.” If you don’t understand that, you are not paying attention.
“– human CO2 emissions are probably (i.e. more likely than not) a major contributor to that warming.”
Nope, it’s 100% certain.
Nothing we know works without including human emissions in the mix.
At the very best, it may be the biggest, but not majority contributor (<50% caused). But nothing else can work with any form of tweaking.
"Politicians and Kings like consensus, they don’t like sceptics and ‘turbulent priests’."
Wrong. They LOVE skeptics if the alternative is making a change that doesn't help their payers. If actions otherwise taken would reduce the concentrated power.
They LOVE that.
Matthew L. #257, is it really safe to gamble that the known and unknown unknowns will tend in the direction of saving our bacon from the threats we know about?
#242 Jimi Bostock
Generally it’s called weather.
However, to address your winter topic:
– with global warming comes warming oceans,
– with warming oceans comes more water evaporation,
– with more evaporation comes more precipitation,
– which of course results in more rain and snowfall.
Here are some extreme earth maps for you:
http://www.ossfoundation.us/projects/environment/global-warming/myths/images/climate-extremes
#244
What your referring to as evidence against AGW are actually claims.
I can say your not human, but is that evidence that you are not human? Evidence needs slightly more substance than you might think.
As to your other points:
Climategate: http://www.ossfoundation.us/projects/environment/global-warming/myths/climategate
Rude? People here are not that rude really. Direct, sure. Attacking the lack of evidence and argument sure. But what is more rude. The presentation of evidence to refute claims or the assertion that claims are evidence?
Cold in winter? generally because the sun places more solar energy on the southern hemisphere in the winter.
It is important to look at the big picture and short term events are still considered int eh realm of weather or natural variability.
http://www.ossfoundation.us/projects/environment/global-warming/natural-variability
http://www.ossfoundation.us/projects/environment/global-warming/temperature
As to “Why do predictions keep not coming true. Why is it so cold.”? You are not looking at the observations, are you?
http://www.ossfoundation.us/projects/environment/global-warming/arctic-polar-amplification-effect
“Not sure how this [is] ammunition for ‘deniers’ – CO2 from anthropogenic activities is still building up in the atmosphere at an increasing rate.”
Because if the oceans are still happily absorbing a lot of CO2 then there is no danger of a “tipping point” due to saturation being reached where sudden dramatic change in climate is a possibility.
Thus humankind can go on for the next 50 years just as it has for the last 50 years with a “wait and see” attitude, expecting only slow change in climate which can readily be adapted to.
The science doesn’t depend on tipping points – but the politics does.
Fed up wrote: “JEP, you’re getting there, but this: ““You’re an idiot and your question is stupid” is unlikely to sway them.” isn’t what’s being done.”
It has been done and it’s been done to me with varying degrees of hostility in the attack. I’ve seen it done to others. It stifles communication. If I ask a question I shouldn’t have to add 5 pages of qualifiers explaining that I’m not a denialist in order to receive a civil answer. Is it bad to wonder out loud what will happen to the biological pump if the artic ocean thaws? Does that make me a denialist? (To someone like me who is largely ignorant of the functioning of the pump the question does have an obvious implication that there might be one positive aspect to thawing the arctic ocean if the pump were to function up there. I have no idea what the relevant rates are likely to be.) I had hoped some knowledgeable person might say something interesting. Instead I was told I shouldn’t ask such questions. (I wasn’t insulted in that particular instance but the attitude was there.) No real scientist can believe that such an attitude is good for science.
One more thing: There is a huge difference between someone asking a question once that others have asked many times and the same person asking the same question over and over and over and refusing to acknowledge the answer.
225: Re the claim that denialists now have momentum. I don’t think they do and they have never been very important. My take on AGW and policy responses to it are that by the mid 1990s the science consensus was settled,
I think you’re right about the science having been more or less settled by the mid 90s. But I don’t agree that the denialists have ever been important. I sat in a scientific review meeting in 1995 or early 1996. There was a program officer from D.C. listening to people explain what they’d done with the money the grant money they’d spent over the past year or two. One guy had done what I thought was brilliant work on ocean modeling. He’d more or less single handedly programmed an ocean circulation model and got it up and running on the big iron of the day (probably the CM-5) and was starting to generate interesting results. In fact the program he started still exists today. But back in 1995 the program officer told him that he could present his results or not but that either way his funding was going to be cut off. The political reasons for this are fairly obvious. At the time people like Dana Rohrbacker were running around saying things like “Global warming is liberal hysteria at best and outright fraud at worst.” Rohrbacker and his ilk had (still have??) considerable clout.
Re 261
Well excuuuuse me! You’ve flown off the handle quibbling over a word. You’re exhibiting a complete misperception of my intent.
Did you read the Chris Mooney article?
I was merely echoing a suggestion – that some of the preponderance of expert amateurs as well as professional climate scientists who provide much of the invaluable commentary as well as airhead deflation take a few minutes to engage with the conservative mob out there and at least help set the record straight in the popular press. I’ll withdraw the “choir” metaphor since my meaning eludes you.
In the spirit of Chris Mooney’s suggestion:
“On issues like global warming and evolution, scientists need to speak up”
http://www.washingtonpost.com/wp-dyn/content/article/2009/12/31/AR2009123101155_pf.html
Or would that be too unsafe for you over at the Washington Post?
BTW, I’ve had pages of climate change links to publications and other resources up on my website since 2003.
http://www.groundtruthinvestigations.com/climate_change.html
I’m finding your tone to be offensive and divisive. Sorry I’m not freaking PC enough for you. You can have the last bark.
David, 217.
I tried Tamino’s two box model with a 1-year and 10-year lag with the instrumental temperature record (concurrent with adjusting for volcanism, anthropogenic forcing, ENSO), and I got more weight on the 10-year exponential lag. About a 2:1 or 3:1 ratio, if I remember correctly. As with most variable, wouldn’t there be a longer term lag due to the time it takes for the oceans to reach an equillibrium response?
At any rate, even with the 10-year lag, the solar contribution to climate peaked in 1981, and is roughly 0.07C cooler in 2009 relative to 1998. 2009 isn’t the second warmest year (or possibly third depending on December) on record because of the Sun. It is warm in spite of the Sun.
257 Mathew L
“Current models assume relative humidity is stable as temperatures increase but empirical evidence is showing it reduces. ”
If you are interested in that topic why not try BPL’s collection here?
https://www.realclimate.org/index.php/archives/2009/12/cru-hack-more-context/comment-page-9/#comment-147201
and for “may even send it negative. ”
you should read Chris Colose at
http://chriscolose.wordpress.com/2009/03/05/what-if-relative-humidity-was-not-constant/
Does anyone have any idea why ScienceDaily issued two different articles on the Knorr findings? One on November 11, another in December. Different articles, referencing the same Knorr article (I even checked the DOI).
Completely Fed Up says:
4 January 2010 at 8:36 AM
“PS tim, what would you say to this site:”
I was approaching the Antarctic Peninsula on a ship last year about this time with a Canadian expedition leader and climate change denialist. When he showed the movie “The Great Global Warming Swindle” to a captive audience on a stormy day at sea I walked out remarking “I feel like the bastards are taking a piss in my head.”
Pretty much my view regarding http://blackswhitewash.com/.
There is a massive, well funded conspiracy being perpetrated by fossil fuel interests to subvert climate change legislation. The stolen emails were timed and orchestrated to cast doubt on climate science as the Copenhagen talks began. These are ruthless, dangerous people. More of us need to speak out to counter the conservative mob echoing their message in every venue they can find.
The problem is that way too many influential folks are persuaded the denialists are right. It’s a clever anti-science campaign. People are believers. They buy what makes them comfortable. I wouldn’t underestimate the enemy in their ability to gratify “consumers” and persuade them to hang onto high carbon lifestyles for dear life.
Thanx Ray.
Thinking a bit further – snow absorbs CO2 as it forms, falls to the earth, let’s say at the antarctic, over time compresses and becomes ice, thus trapping the CO2 content. Can this new ice absorb/release CO2?
Steve, see if they mention a source for the articles.
Usually Science Daily is just reprinting press releases.
I recall a publication with three authors — each from a different university. The first university rushed out an incorrect press release within days; the third one, home of the senior author, sent out a good press release after a week. The bad one got all the press. Might be a similar situation here, different authors, different PR departments.
Just guessing.
JEP: “It stifles communication.”
Communication requires some INFORMATION to be passed around.
most of the time there’s no information in the questions. Just sound and fury, signifying nothing.
Just like when your five year old keeps asking “why?” when you answer a question.
Communication is also two-way, if a response is going to be sent.
But note the number of zombie questions.
Dave Bassage asks about this claim: What most people don’t understand is that CO2 is more dense than air so stays near to and even sinks into the ground. If this wasn’t so then plants would suffocate & there wouldn’t be any land based life at all.
Whoever makes this claim has seriously misunderstood the basic mechanics of gases. You may want to point them to references on Maxwell-Boltzmann statistics and partial pressures.
re#263.
Dont panic. We have already adapted to 388 from ….approx 250 or so, and we are healthier now, for lots of reasons. No need for alarm for health reasons,
#275 – Geoff Wexler
Thanks for those, very useful. I have read a couple of the BPL cited papers – he is a very useful source. I don’t dispute at all that water vapour increase is a positive feedback, however the key phrase in Chris Colose’s post is:
“So, if RH were actually declining, it could simply be that the water vapor feedback is positive but less powerful than the mainstream science suggests”.
The total positive feedback budget in the models used by ‘mainstream science’ is what drives the increase in temperatures predicted over the next 90 years. If the overall positive feedback from water vapour is lower than previously thought, and a negative feedback becomes apparent (such as a negative temperature effect from increased cloud) then a significant element of the presumed warming over the next century may not happen.
I would stress my concern is not that the science is somehow wrongly done, but that our picture of the ‘engine’ driving the climate is incomplete and therefore the outcomes from the models maybe significantly more uncertain than current models show.
I question whether it is worth going to (metaphorical) war over the single issue of CO2 when there are much more current, certain and devastating problems that need tackling. We may reduce global emmissions of CO2 but while our backs are turned the fish have all gone, the forests burnt to dust, all the big primates dead and the rivers sucked dry. These are often cited as consequences of AGW, but actually they are the consequences of direct human action. They would happen whether global temperatures rise or fall.
For those paranoid about the choir and the consensus (as I can be at times) could someone point us to examples of robust disagreements and challenges at some time in the past among the current choir members and how those disagreements were/have been resolved? I belabor, yet again, the obvious fact that the amount of data, proxies, etc. is overwhelming, especially when one can look at 50 years or 50 million years. And even more overwhelming is what has been done with and to the data.
The greatest fear out there among reasonable people is that this much-tweaked data got nudgeded consistently in ways which always eventually confirmed, or at a minimum never negated the thrust of AGW assertions.
It is discouraging that even what should be a simple assertion about whether the weather has warmed, cooled, or stayed the same for the last ten years is clouded. Ask that question; The responses? “You idiot, it has obviously: A. warmed B. stayed the same C. Cooled D. It is too soon to say because it is only 10 years E. Don’t forget that you really are an idiot, dupe, or ideologue because you have not already decided (which can be said with gusto by either side, although I will grant that the blather of the right is LOUDER, for sure).
But hey, it’s the internet where “robust” conversations happen all the time, right?
Matthew L. says: 4 January 2010 at 9:12 AM
“Being an older guy I have seen many environmental and energy crises come and go…”
Matthew, can you quickly name five environmental crises that were identified by scrupulous research and which then went away all by themselves?
#260 Ray,
I think you are over-reacting a touch. I am not dismissing any science, just suggesting that there is plenty of room for new discoveries.
Just because a science is ‘mature’ does not make it ‘complete’. With Newton’s help astronomy and astrophysics were very mature before Einstein came along and turned it all upside down. There is still plenty of room in climate science for big shocks, paradigm reversals and major discoveries. I am not saying there necessarily will be any shocks, but to say with any certainty that there won’t be any is a bold call in such a massive and complicated scientific field.
You state that the greenhouse gas theory has been known since 1824 yet 186 years later we still do not know the effect on the greenhouse effect of the most obvious feature of our climate and weather – the clouds. And it is not just the clouds – what about the PDO, NAO, ENSO? Do we know really know everything there is to know about ocean currents and their effect on global warming?
What you are stating is that the models and constraints are mature and well tested, but that is assuming we know all we need to know about the underlying mechanisms driving climate.
You really say it all in your first paragraph. “Yes, clouds remain a big uncertainty. So do aerosols.”
Quite – and there are the unknown unknowns as well. That is my point.
Ryan (#270) said:
Talk about famous last words. What do you think “tipping point” means? If your cup is still happily filling up with coffee does that mean it will never brim over? Think.
(That’s just a comment on the logic of tipping points in general. It is not to say we’ll reach a tipping point in ocean CO2 uptake as if the “cup” metaphor applied. On the contrary I believe a gradual slowdown is expected.)
Leo G., Gas transport in ice is slow but nonzero. This is why ice cores are able to give us a picture of temperature and CO2 going back ~600000-800000 years.
Todd Friesen (274) — Tamino makes the point that a 30 year characteristic time agrees quite well with ModelE; that is presumably the characteristic time to affect the whole mixed layer ocean. So now we have quite a puzzle. Various studies indicate that the response to the solar sunspot cycle is in the range 3/4 to 2 years; Tung and co-workers suggest less than 1 year is most likely.
The effects noticed in Usoskin et al. ought, IMO, be quite small but I don’t see anything wrong with their correlation analysis. Try a two box model with characteristic times of 10 and 30 years and then a three box model with characteristic times of 1, 10 and 30 years. Do either of these do better than Tamino’s and your 1 and 10 year model, and if so, is the improvement statistically significant?
Dwight (285) — You’ll find various disagreements mentioned in “The Discovery of Global Warming” by Spencer Weart, first link in the science section of the sidebar.
Matthew L., What you are ignoring is all the different lines of evidence that show us that CO2 sensitivity is more than 2.1 degrees per doubling and most likely 3 degrees per doubling. Now why would you be ignoring that. The damage that could result from climate change could negate any progress we make on any of the other issues you raise. At present it is the only issue that poses an imminent threat (~100 year timeframe) to the continued viability of human civilization. I consider that worth fighting for.
Bill, it’s not solely _your_ health that matters, and not only mammalian respiration. Adaptation is wishful thinking.
http://www.int-res.com/articles/theme/m373p285.pdf
Dwight asks: could someone point us to examples of robust disagreements and challenges at some time in the past among the current choir members and how those disagreements were/have been resolved?
Serendipitously, we have Gavin’s new post, The carbon dioxide theory of Gilbert Plass, which fits the bill nicely.
Dave Bassage @238, your “skeptic” has either never learned anything about how the atmosphere works or is hoping that you haven’t. You might suggest that he read up on temperature-driven convection and pressure gradient driven wind and turbulence as they are what insure that CO2 is a well mixed gas throughout the atmosphere.
That said, his example of people who live in valleys suffocating does in fact rarely happen in instances of still air and temperture. Try googling Lake Nyos, Cameroon:
http://en.wikipedia.org/wiki/Lake_Nyos
Gavin, might I suggest a post called ‘Arguing in the noise while drowning in the signal.’ or something to that effect.
To those worried about the tone of this debate: yes, it’s true. Supporters of the Anthropogenic explanation of climate change can be testy at times when arguing, especially on the internet. But you have to keep in mind the company you’re in.
We don’t and shouldn’t claim to be omniscient or sinless, but for the most part, such reasoned commentary as you see here comes from people who are keen to understand the problem and its consequences. I can’t speak for others, but I’ve found that once you get down to it, that the consequences are frankly terrifying.
The way in which the arguments unfold is a testament to the anonymous and democratic nature of the internet. An intelligent eleven-year-old in Tulsa can post something inspired by his father’s latest rant against the “elitist scientists and their crazy theories” and reach a hundred million people. A marine biologist can talk about his latest research on the effects of ocean acidification on coral reefs and reach just as many. The vast majority of people reading might find the the eleven-year-old’s commentary is funny, cogent, something that they can connect to. The marine biologist’s piece, however, is boring, depressing, perhaps incomprehensible to most people.
I’ve found that writing thousand-word posts in response to the most vocal deniers is generally a waste of time- I’ve been accused of just “posting a bunch of crap,” when I feel that I explained my position and the evidence behind it to the best of my ability.
Being a denier puts you in poor company. It puts you in the company of people who think that “Liberals and Gorons do not require proof of anything, no scientific method, tests, history, nothing is required. The only necessary proof needed is their “feelings”” is appropriate commentary.
http://www.delawareonline.com/comments/article/20100101/OPINION10/91231029/The-evidence-of-man-made-global-warming-is-missing
(Full disclosure- I’m the Propergander you see in that thread)
Being a denier puts you in the company of people who have no idea how to think scientifically. I had one denier claim that an analogy where I compared Earth’s heat budget to a household budget was wrong because I didn’t take into account how “obvious” each of the factors I named was. Thinking scientifically, I had listed the factors by magnitude. “Obvious,” being so subjective, never entered into my mind.
If we seem rude, it’s because each of us has likely had dozens of similar interactions and have concluded some very uncomplimentary things about the mentality of those who deny anthropogenic global warming. So please, consider not just our rudeness, but the illogical, rude, and just plain crazy people that you have chosen to surround yourself with.
You AGW folks have a real problem in logic. You have to insist that the evidence for catastrophic AGW is beyond debate, which is a very difficult line to take. The skeptic’s line is merely that catastrophic AGW is debatable. So if you debate you have conceded their argument. You have to take what I call the “Gore defense,” which is refusing to debate. This makes you appear unscientific, because debate is at the heart of science.
David
[Response: Sorry, but it is you that have it all wrong. The issue is not whether we can prove whether AGW is catastrophic (a strawman argument), but whether the risks of continually increasing CO2 emissions are worth hedging against. By defining the problem your way, you close yourself off from ever acting in the absence of 100% proof of catastrophe (an impossibility prior to any such event), and thus paint yourself into a denialist corner from which no discussion will ever draw you out. And you wonder why people don’t waste time talking to you? – gavin]
I am currently developing an online non-majors course on climate change biology.
Any suggestions for books that cover both the physical and biological aspects of climate change at a level appropriate for non-science majors?
Thanks!
Yet how many armies had to recompute their artillery tables after Einstein “turned physics upside down”?
None.
Why? Because the errors introduced by using Newtonian physics are very small, one might say tightly constrained, under normal circumstances. Even before Einstein we would’ve known if Newtonian physics was grossly wrong at that scale, due to observations (apples falling up from trees, not down, etc).
That’s what Ray’s trying to get you to understand about climate. There are undoubtably “known unknowns”, but enough is known about climate from multiple lines of evidence that there’s extremely high confidence in climate sensitivity to CO2 doubling being constrained to the range given by the IPCC.