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bjchip at 06:26 AM on 25 August 20132013 SkS Weekly News Roundup #34B
One notices that the "Mega Hearing" questions include not a single question relating to how bad climate change is actually likely to be for the USA over ANY span of time. One has to wonder at their ability to ascertain that they already know all they need to know about this part of the issue.
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One Planet Only Forever at 06:11 AM on 25 August 2013Carbon Economics and the Cost of Inaction
Re my Comment 2:
A correction in the 4th para: "These types of activity should never "be protected", and their potential impacts certainly should never be "balanced" with someone's or some group's evaluation of their personal benefit in their moment.
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One Planet Only Forever at 06:06 AM on 25 August 2013Carbon Economics and the Cost of Inaction
Comparisons of "the cost to, or lost benefit of, a current generation" compared to the "costs created for a future generation by the actions of a current generation" are fundamentally unjustifiable. And applying a "net-present-value" discounting of future costs, which is often applied to such evaluations, is an added insult to the already unjustifiable attempt to excuse benefiting from creating a future problem.
The future generation is not a "set of shareholders in a business operation". The future generation cannot just declare bankruptcy to minimize their costs at some time in the future and "invest in a different planet".
So it is unjustifiable, and simply not sustainable, for actions by a current generation to create a potential consequence or problem for future generations. The development of unmanageable conditions in the future needs to be stopped. All activities of any current generation need to either be of no future consequence or preferably lead to a sustainable better future for all life on our one and only shared planet.
The challenge for the current generation is to figure out how to undo the unacceptable industrialized mass consumptive economies that have been developed by our predecessors. These types of activity should never "be protected", and certainly should never be "balanced" with someone's or some group's evaluation of their personal benefit n their moment.
As much as possible this change of economy and lifestyle should be accomplished by all of the most fortunate being required to develop the ways to live totally sustainable lifestyles and help the lss fortunate develop to that way of living with as little time as possible spent transitioning through industrial mass consumption activities and ways of life.
The entire population can sustainably live on our planet, as long as those whose lifestyle and ways of benefiting have the highest impact are required to change their ways.
So the real required action is political motivation of the most fortunate to spur the scientific development of the understanding required to lead to those best ways for humans to truly sustainably live on our one and only planet.
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John Hartz at 00:55 AM on 25 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
Mark Harrigan: Lest there be any confusion, here's what the Comments Policy says about "excessive repetition."
Comments should avoid excessive repetition. Discussions which circle back on themselves and involve endless repetition of points already discussed do not help clarify relevant points. They are merely tiresome to participants and a barrier to readers. If moderators believe you are being excessively repetitive, they will advise you as such, and any further repetition will be treated as being off topic.
This is your second and final warning about this policy. If you post repetitive comments in the future, they will be summarily deleted.
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Mark Harrigan at 23:42 PM on 24 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
@ Michael,
With due respect what you did was make a snide attack that my comments were a "Gish Gallop" - now you use condescending language like "spoon feeding".
Do you really think this is a constructive way to debate?
You also misrepresent me. At no stage did I say renewables are more expensive. I stated facts. 1) that the cost of switching is not zero 2) The economics of costing energy (fossil and renewables) is complex, 3) It is necessary for renewables to have nameplate overbuild in order to gain significant penetration of the overall supply (read the AMEO report on this) and (4) that not infrequently such costings ignore the grid transmission costs (BZE being one)
Nor did I ever claim "it might not be too bad". I simply stated that is a fact that projections of climate sensitivity include the possibility that this is low. (To be clear my personal worry is this is not the case)
Please re-read my original post more closely.
Also - I don't what to have a debate here about renewables costs. As the moderators rightly point out such a detailed debate is off topic (although you might like to look at this http://www.ted.com/talks/david_mackay_a_reality_check_on_renewables.html ) I was however talking about the relative costs of renewables versus the costs of damage as being relevant to Andrew's argument
My main point was that Andrew's logic is basically that we can take action with no regrets. That is not true under a scenario where climate sensitivity turns out to be low and costs of renewables exceed our optimistic expectations.
Instead of assuming I make "wild claims" perhaps you should open your mind to arguments and debate from someone who is saying that the arguments made by Andrew (which are generally pretty solid) need some work?
Moderator Response:[JH] You have made your point. It's time for you and others to move on.
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Mark Harrigan at 23:13 PM on 24 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
@ Scaddenup You and other seem to have misinterpreted me. And climate sensitivity is not the topic of this thread (although clearly it is not entirely irrelevant given the nature of Andrew Dessler's argument).
However the IPCC clearly supports a response to doubling of GHG emssions to be possibly less than 2 degrees - as indeed this site itself makes clear http://www.skepticalscience.com/graphics.php?g=88
Of course it is equally likely it may be very high. But I am not specualting either way (personally I worry it will be high as the ocean heat capacity - while enormous - is not infinite and we do not yet know enough about long term ocean circulation to be unconcerned - if the heat currently stored there does find it's way into the atmosphere in the near term that is a huge problem)
My point, which apparently I have not made clear, is that Andrew's argument needs to be buttressed. Because if climate sensitivity does turn out to be low (fingers crossed) and the costs of renewables do turn out to be high (a possiblity that cannot be ruled out) then taking action is NOT a no regrets policy.
Perhaps you should read Nordhaus? His economic analysis is quite clear that there is a point at which taking action becomes economically non-viable (i.e. costs of action are higher than the damage avoided). The interesting debate is where that occurs (none too easy to establish but important none the less)
Moderator Response:[JH] You have made your point. It's time for you and others to move on.
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Shizel at 23:03 PM on 24 August 20132013 SkS Weekly News Roundup #34B
We don't have time for civil disobedience. After 40 years of nuclear protest, all we have to show for our troubles is Fukushima and 60 brand new nuclear plants under various stages of completion world wide. I believe we should commit to Hansen's 100% private no-split carbon dividends using a new world e-currency. This will unite the people of the world and undermine the government-military-corporate hegemony. I also believe we should support Hansen's 4G nuclear research project. We cannot safely store nuclear waste 10,000 years when we can't even be sure of our own survival over the next 100 years. Nuclear denialists usually attack this idea with the same fevor and tactics Fox News uses against climate scientists. This schizm underlies the fultility of searching for the magic uprising narrative.
FUN WITH NUMBERS
The acidity of the oceans will more than double in the next 40 years. This rate is 10 times faster than 55 million years ago when when a mass extinction of marine life occurred. It is also faster than during 4 of earth's biggest mass extinction events during the last 300 hundred million years -- faster than even the great Permian mass extinction event where 95% of life on earth vanished 250 million years ago. The oceans are now 30% more acidic than in pre-industrial times. In less than 40 years they will be 60% more acidic than then.
http://en.wikipedia.org/wiki/Ocean_acidification
http://www.youtube.com/watch?feature=player_embedded&v=dQJHJ6dbhsA
http://thinkprogress.org/climate/2013/05/08/1976351/acidification-arctic/
http://www.earth.columbia.edu/articles/view/2951
http://readthescience.com/2012/09/17/climate-change-book-review-under-a-green-sky/
http://www.youtube.com/watch?v=cPgfnwi2m9M&feature=player_embeddedWhen ice ages come and go the planet can change temperature 5°C in as little as 5,000 years. 50 times slower than what we are doing to earth now. In the past, a 5°C change normally takes 20,000 years, we are going to do 5°C in 50-100 years, 200 times faster.
http://earthobservatory.nasa.gov/Features/GlobalWarming/page3.php
http://oceanservice.noaa.gov/education/pd/climate/factsheets/iscurrent.pdfClimate change is happening 100 times faster than in the past.
http://www.scientificamerican.com/article.cfm?id=todays-climate-change-proves-much-faster-than-changes-in-past-65-million-yearsBy 2025, humans will impact 50% of earth's biosphere. This will cause a planetary ecological state shift leading to a mass extinction event that is unstoppable and irreversible once started.
http://www.youtube.com/watch?v=D-UjEaCoVVU
http://www.ecoshock.info/2012/06/planet-shift-no-return.htmlWhy does nobody talk about the thousands of 1-kilometer wide bubbling methane seabeds recorded in 2011.
http://www.independent.co.uk/news/science/vast-methane-plumes-seen-in-arctic-ocean-as-sea-ice-retreats-6276278.htmlOnly 1% of methane needs to be released to cause total disaster.
Peter Wadhams interview
http://www.youtube.com/watch?v=_biGUz6ACBgNatalia Shakhova interview:
do you believe scientists
who spent 30 years in the arctic
or do you believe scientists
who spent 30 years at their computer?
http://www.youtube.com/watch?v=kx1Jxk6kjbQ -
chriskoz at 16:40 PM on 24 August 2013Fasullo (2013) Seeks Some Levelheadedness Regarding Sea Level Variability
Thanks for the article, John.
The text answers the two of your bullet points:
- why have drops of similar magnitude not accompanied other La Niña events in the altimeter era? (coincidence of MEI and IOD & SAM is required as seen on figure 3c)
- how can rainfall anomalies over land be responsible for such a prolonged drop? (because of unique shape of the AU continent whereax the runoff goes into lake Eyre)
But the answer to the third bullet point:
- how frequently do drops similar to the one in 2011 occur? does evidence exist in the historical record for other such drops?
does not apear obvious to me, because I don't have access to the full text. I've downloaded figure S4 and I can see the rainfall map from the 1973-74 event (setting the famous record flood levels in Brisbane for those who remember) showing the anomaly in the central basin as wide spread as the latest one. Obviously, that was before GRACE era, but I suspect the event should have left a discernible dip in the gauge record. Such dip (of 6-7mm) would have been the evidence answering that bullet point. Did you find it or was it to small to find?
Second question, what do you mean by "dominant contributor" in terms of the actual numbers? Did you establish an approx percentage of the contribution based of GRACE mass numbers?
Thanks again for a great piece of reaserch.
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Tom Curtis at 09:49 AM on 24 August 2013Carbon Economics and the Cost of Inaction
I suspect the graph shows GDP/capita. If not, it is missing a quantifier on the y-axis.
More importantly, the GDP growth scenarios are just that, scenarios. They are inputs into determining the forcing trajectory of the various scenarios rather than outcomes of applying those forcing scenarios to an economic model and determining the consequent rate of economic growth. As such they are not evidence for the thesis of the OP. I say this even though I agree with that thesis, ie, that the costs of inaction are greater than the costs of action on climate change.
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StBarnabas at 08:49 AM on 24 August 2013Fasullo (2013) Seeks Some Levelheadedness Regarding Sea Level Variability
John
great post thanks. Good to see the science going forward. Many thanks again. I am becoming more optimistic that good science rather than disinformation is winning the day. A year ago I was deeply depressed that we were entering a new dark age.
StB
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Matt Fitzpatrick at 07:50 AM on 24 August 2013Fasullo (2013) Seeks Some Levelheadedness Regarding Sea Level Variability
Ah yes, 2011. The year sea level drop was supposed to be the "final nail in the coffin" for global warming.
So many blogs claiming that the sea level dipping back to 2007-ish levels was somehow a lasting reversal of a decades long trend. Excoriating the climate models. Ridiculing NASA for—accurately, as it turns out—calling it a "pothole". Even halfway out of the "pothole" in 2012, some were still cherry picking those last few months to claim "no upward trend".
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Rob Painting at 06:08 AM on 24 August 2013Fasullo (2013) Seeks Some Levelheadedness Regarding Sea Level Variability
A highly informative post. Thanks.
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John Chapman at 00:31 AM on 24 August 20132013 SkS Weekly News Roundup #34A
Oops, that was a bit silly of me.
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A grand solar minimum would barely make a dent in human-caused global warming
Stealth - Two small but, I believe, significant points:
The references you gave for variance of insolation reaching the ground in this post are for decadal variations, in particular mid-century dimming (1950's-1980's), the well known cooling associated with high aerosols, and in fact discussed on SkS. They also discuss some indications of higher aerosol cooling in the last decade, considered as a potential influence (although not dominant) in 21st century temperatures. Aerosols are a known forcing, and variations in insolation are generally treated separately based on satellite observations. And they are not short term variations.
The uncertainties you mentioned in the Trenberth energy budget (I'm speaking of Trenberth 2009 are uncertainties in absolute values, not variances. You seem to imply a 34 Wm-2 variance in energy imbalance, which is not what that paper is stating. In fact, what they say is:
The TOA energy imbalance can probably be most accurately determined from climate models and is estimated to be 0.85 ± 0.15 W m−2 by Hansen et al. (2005) and is supported by estimated recent changes in ocean heat content (Willis et al. 2004; Hansen et al. 2005). (Emphasis added)
Again, anomalies are very important, telling us how much these values have changed - not the absolute numbers. And uncertainties in TOA imbalance are highly constrained by other observations.
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Mark Bahner at 11:12 AM on 23 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
“Mark, you have been given incisive and complete answers to this, on this forum and in Dessler's video.”
That is demonstrably false. I will give you $200 if you will identify the point in Dessler’s 6-minute video in which he states:
1) What percentage probability is associated with the word “may” (i.e., “a 50 percent probability” or “a 10 percent probability” or “a 1 percent probability”, and
2) What he means by “severe” (i.e., “global surface temperature change greater than ‘x’,” “sea level rise greater than ‘y’, ”reduction in life expectancy greater than ‘z’, etc.)Moderator Response:[DB] "That is demonstrably false"
This is tiresome. Please demonstrate where "on this forum" (not just in the video) you have not been given your "incisive and complete answers".
You will be held accountable to this.
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Bert from Eltham at 11:08 AM on 23 August 2013Bulletin of the Atomic Scientists: Closing the Consensus Gap
I am amazed at your ability to cherry pick red herrings joeygoze. It is a shame you missed my Freudian slip in calling John Cook's paper 'Qualifying the Consensus' instead of Quantifying the Consensus. The irony is by quantifying the consensus one can then qualify the consensus! This point has completely eluded your obvious talents. Bert
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scaddenp at 10:53 AM on 23 August 2013A grand solar minimum would barely make a dent in human-caused global warming
I dont actually understand where you get your 34 "window" for solar, but I cant see how that diagram can tell you anything about stability of solar radiation reaching the earth (for which you need a time dimension). The error bars about the limitations of the measuring systems, but given that solar at TOA is very stable, if you claim that energy is not reaching the surface, then the imbalance is being stored in the atmosphere. Does that sound better to you somehow? More to the point, where is the evidence for storage of that kind of imbalance in the atmoshere? On the other hand, OHC changes match pretty well with the imbalance.
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A grand solar minimum would barely make a dent in human-caused global warming
Stealth - There's plenty of regional variation in atmospheric transmission and albedo from clouds. However, global temperatures both surface and in terms of OHC show a rise that indicates an average imbalance of between 0.6-0.9 W/m2 over the last 50 years. That means the global variation of TOA imbalance is quite small over any reasonable time period.
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StealthAircraftSoftwareModeler at 07:53 AM on 23 August 2013A grand solar minimum would barely make a dent in human-caused global warming
All: my apologies. I made a mistake and started too many conversations @12. I tried to respond to all of the issues I had with Dana’s article and I should have kept it to just one. Let me back up and do some homework on ocean heating. I may even go look at Argo data and play with it a little bit.
I’d like to restart and focus just on Dana’s multiple comments stating “the amount of solar radiation reaching the Earth’s surface is very stable.” I do not think this is true at all. I think Wild 2009 and 2012 (referenced above) both claim the opposite, and Kiehl and Trenberth’s energy budget (http://curryja.files.wordpress.com/2012/11/stephens2.gif) has a huge 34 W/m^2 window (30 times the effect of CO2 forcing). This clearly indicates there is a lot of variance in surface energy, or it is hard to measure, or both. In in case, it is not stable.
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joeygoze9259 at 07:30 AM on 23 August 2013Bulletin of the Atomic Scientists: Closing the Consensus Gap
Newyork J - I think the fact that 6 skeptical papers got into the "support AGW" column is reason enough to suspect a methodology problem and this unfortunately weakens the conclusion of the study.
Tom Curtis - I was not suggesting data was hidden, was honestly asking for someone to point me to the data
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scaddenp at 07:24 AM on 23 August 2013A grand solar minimum would barely make a dent in human-caused global warming
Stealth, you quote a line from Stephens to support your case. I note that you didnt quote the very next line.
" Specifically, the longwave radiation received at the surface is estimated to be significantly larger, by between 10 and 17 Wm−2, than earlier model-based estimates."
Now that doesnt sit well with the idea that uncertainities make any action unwarrented, or that science is overestimating AGW.
Your statements on Kiehl and Trenberth (you dont say which paper), dont seem to fit that well with Trenberth et al 2009. While they note the difficulties in surface budget, note:
"Therefore, we have a lot more confidence in the values we have assigned than indicated by the spread within the tables. TOA values are known within about ±3% or better, except that the net is (or was) 0.85 ± 0.15 W m−2 (Hansen et al. 2005), and surface fluxes are constrained within 5% except for solar-reflected, LH, and LW, where errors may be as much as 10%."
Note the TOA estimate is well constrained. If energy isnt leaving to space, where is it and why do you think the TOA imbalance is not a problem?
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davidnewell at 04:45 AM on 23 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
Rob Honeycutt @ 21. Great response, there's always the "outliers" who are facile in their characterizations of "what is happenning."
"Reality", however, is not dependent on whether or not a vote is taken.
I hold out a consistent hope that the existential "Reality" of the potential end of "everything of value" on this Planet, (which I call Gaia just because some of y'all love the term muchly) ":<)
will cause a paradigm shift in how we relate to one another.
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How does one put a "cost" on an activity which may -stop- further evolution on the planet? And then price a gallon of gasoline to offset it?
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A grand solar minimum would barely make a dent in human-caused global warming
Stealth - You were involved in a long discussion of IR/ocean heating here, including the accuracy of OHC measurement, and in a discussion of the human contribution to warming here (thanks go to Google Search).
Yet your post on this thread repeats some of the very same misunderstandings.
It would be helpful if you were to avoid restarting discussions on another thread - without any apparent acknowledgement of either prior discussions, or the responses people have provided, as if the questions had never been addressed.
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davidnewell at 04:17 AM on 23 August 2013How much will sea levels rise in the 21st Century?
Thank several of you for correcting my misunderstanding of the aggregate production of CO2 by China, for the actual annual production by 2100.
I personally appreciate jja @ 16, interspersing his comments with "magical thinking" perjoratives.
It's one thing to be a chicken little "The sky is falling" alarmist: it's another to actually have the equivalent becoming manifest.
In regard to
" If global temperatures rise, the warmer world will radiate more energy back out into space and the energy imbalance will reduce"
being a salient response to a "+7C" increase by 2100...: well, I am speechless.
We must derive a doable "Direct Air Capture" technology.
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A grand solar minimum would barely make a dent in human-caused global warming
Stealth - I would agree with Tom Curtis - claiming that the uncertainty of multiple measurements from almost 4000 ARGO floats is identical to the error of a single measurement is absurd, and anyone with science or engineering background (which you claim) should be well aware of this aspect of signal averaging, right along with the Central Limit Theorem.
OHC is an anomaly measure, not an absolute measure, and hence the link you provided regarding absolute measures is wholly irrelevant. Use of anomalies also removes any potential systemic bias in those measurements.
Your last few comments appear to be (IMO) increasingly disingenuous.
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Tom Dayton at 02:51 AM on 23 August 2013A grand solar minimum would barely make a dent in human-caused global warming
Stealth, to follow up on Tom Curtis's reply to you, read about the Law of Large Numbers.
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Tom Curtis at 02:24 AM on 23 August 2013A grand solar minimum would barely make a dent in human-caused global warming
Stealth @17, as I understand it, the uncertainty of the mean of n values, each with uncertainty x equals x/(n^0.5). Your claim that the increase of OHC in within the error bars presumes either that there was just one measurement (for the whole ocean), or that the error of measurement is entirely composed of a systematic bias. Please put forward your evidence of either proposition.
Absent that evidence, you appear to be guilty of deliberate obscuring of the evidence (assuming that, as a scientist, you know the basic mathematics of uncertainties).
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StealthAircraftSoftwareModeler at 02:05 AM on 23 August 2013A grand solar minimum would barely make a dent in human-caused global warming
KR @14: Minnett 2000 and the A High-Accuracy, Seagoing Infrared Spectroradiometer paper (http://journals.ametsoc.org/doi/pdf/10.1175/1520-0426%282001%29018%3C0994%3ATMAERI%3E2.0.CO%3B2) point out that their “high accuracy equipment” has stated accuracies of 0.1K. The entire OHC content anomaly when converted from Joules back to temperature in the ocean is on the order of 0.09C (I assume you can do the math and conversion, but if not let me know and I’ll show my work). Clearly, OHC is within the error bars of the measurement system, unless Argo can measure more accurately (unlikely). It could be there or it might not be – it simply is too small to measure. Then, when combined with the number of measurements and uncertainties induces by thermal eddies and ocean mixture, it is seems unlikely to me that measurements can tease out the true OHC.
Finally, I believe OHC from NOAA suffers from modeling artifacts like surface air temperature (SAT). Please see Dr. Schmidt’s discussion of SAT at NASA GISS: http://data.giss.nasa.gov/gistemp/abs_temp.html
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Composer99 at 01:51 AM on 23 August 2013A grand solar minimum would barely make a dent in human-caused global warming
Stealth:
I would have thought your misconception regarding TOA vs surface energy balance and their respective significance with regards to global warming has been previously addressed, so I confess I am surprised to see you re-state it here.
I should also add that you appear to engage in cherry-picking. Stephens et al 2012 has to be considered in context with other papers of the same nature. As far as I have seen you have provided no analysis doing so. At the very least if you feel Stephens et al by itself outweighs any (or indeed every) other similar paper, it is down to you to show your working.
Finally, with respect to your assertions about NOAA vs ARGO, unless you yourself provide evidence (*) to support your claim, no one has any obligation to accept it as correct.
On that note, the opening paragraph of Levitus et al 2012 states:
We provide updated estimates of the change of ocean heat content and the thermosteric component of sea level change of the 0–700 and 0–2000 m layers of the World Ocean for 1955–2010. Our estimates are based on historical data not previously available, additional modern data, and bathythermograph data corrected for instrumental biases. We have also used Argo data corrected by the Argo DAC if available and used uncorrected Argo data if no corrections were available at the time we downloaded the Argo data. [Emphasis mine.]
So the data you deride uses the very same floats that Svensmark claims "have not registered any increase in temperature" and finds... that they have.
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(*) Evidence other than an appeal to your qualifications, I might add.
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StealthAircraftSoftwareModeler at 01:47 AM on 23 August 2013A grand solar minimum would barely make a dent in human-caused global warming
Sphaerica @ 13: I followed your link and “read more”, but the link seems to support my statements @12. You may not like the information because it doesn’t support a CAGW position, or it shows that Dana is incorrect, but that doesn’t mean I am “preaching.” I fully admit I may be incorrect in my statements or have misunderstood something, and if so, please correct me. What in my statements @12 are wrong?
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A grand solar minimum would barely make a dent in human-caused global warming
Stealth - Svensmark is in fact flatly wrong in claiming the ARGO probes "...have not registered any temperature rise", and you are equally off-base in claiming "...Heat Content is some output from a software model, not direct measurements...".
Temperatures measured by the ARGO floats and the XBTs before them are rising in the raw data, and the ocean heat content (OHC) is simply observed temperature change scaled by the thermal mass of the ocean layer in question - not some kind of complex model. OHC cannot be dismissed by appealing to model complexities.
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OHC may be one of the best measures of the top of atmosphere imbalance available - averaged over long time periods, global, representing (for the full depth of the oceans) ~93% of the energy changes. And it is consistent with satellite observations of TOA flux (Loeb et al 2012). Adding up components of the Earth energy budget (evaporation, thermals, clouds, albedo, etc) sums estimate uncertainties - but OHC is a direct measure of TOA imbalance.
In addition to Sphaericas link on ocean warming/IR, I would also point out a RealClimate discussion of the same work.
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2013 SkS Weekly News Roundup #34A
John Chapman - That's mm/yr, not cm/yr. 3.2mm/yr * 10 is 32 mm, or 3.2cm, or about an inch and a half per decade.
3.2mm plus 0.013mm/yr acceleration (Church and White 2006) leads to a total of about 33-34cm by 2100. That, however, doesn't figure in temperatures - semi-empirical modeling of temperature versus sea level (Vermeer and Rahmstorf 2009 for one example) predicts 90-170cm for middle-range temperature scenarios.
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John Chapman at 00:56 AM on 23 August 20132013 SkS Weekly News Roundup #34A
Roger Pielke's dissent represents 7% of the 14 AGU members, so that's consitent with the 95% consensus figure!
I note tow of the articles mention sea level rises. One at 8 inches by 2050 and the other 3 feet by 2100. Recent rates of rise have been reported at near 3 mm per year, which equates to almost a foot per decade indicating rises of 3.5 feet by 2050 and over 8 feet by 2100, and that's without an acceleration of the rise. Why are those projections inconsistent with recent measurements?
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MA Rodger at 21:49 PM on 22 August 2013How much will sea levels rise in the 21st Century?
jja @39.
The 5ZJ for 50mm SLR was calculated @30 to be 5.5ZJ (rather than approximated @19). Of course this exrtra 10% energy requirement is minor but I mention it here for the sake of correctness.
I'm on board with your estimates down to the paragraph beginning "If Atmospheric temperature is increased to +7C by 2100..." Here we hit a profound problem. If global temperatures rise, the warmer world will radiate more energy back out into space and the energy imbalance will reduce. The larger that temperature increase, the greater the reduction in (inward) energy imbalance, this being accentuated if ECS is small (a situation that is quite fun when denialists try picking up on energy fluxes to support their fantasies). So to achieve 2,494 - 3,483 ZJ global energy flux to 2100 would require all surface warming to stop over that period.
A +7⁰C global temperature rise (above pre-industrial values) with ECS=4.3 would result in increased outward radiation of 5.3 W/m^2 or 86 ZJ pa. Subtracting this would make your 58 to 81.2 ZJ pa negative, although I would assume your +7⁰C was assuming long term positive feedbacks which are usually considered additonal to ECS.
Your final estimated values assume that energy imbalance will increase as additional RF accumulates. That is a big assumption. I would suggest that taking the rate of change of RF (ie ∆RF) as a proxy for energy imbalance may be a useful first assumption. Present levels of net RF are difficult to quantify but positive RF are better quantified with ∆RF = 0.043 W/m^2 pa over recent decades. Continuing at that rate would give an additional 3.7 W/m^2 by 2100. This does not provide a basis for projecting a significantly larger ∆RF over the coming century and thus no large increase in future energy imbalance can be inferred from such a consideration.
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Bob Lacatena at 13:54 PM on 22 August 2013A grand solar minimum would barely make a dent in human-caused global warming
Stealth,
Preach less, read more. Your understanding of ocean warming is wrong.
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chriskoz at 13:34 PM on 22 August 2013Coumou & Robinson on Extreme Heat: Choose Your Own Adventure
Tom@1,
I would not be so sure that "observations overshoot the model projections" for the event shown on figure 2. You cannot say that unless you have and compare the actual data. Eyeballing may be very subjective. For example, having downloaded the high quality picture, my eyeballs concentrated on large swathes of dark blue coloured 1-SIGMA observations in NAmerica, Siberuia and WAus, whereas the models paint it light blue or green, thus models overshoot the observations there.
Your question:
is the percentage of land area shown represent the percentage of total land area or the percentage of actually observed land area?
can only be answered the the authors. But I think it should the the latter (of actually observed land area), if they did not interpolated the grids with no data; otherwise it would not make sense in the context of comparing the observations with the model predictions.
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StealthAircraftSoftwareModeler at 13:24 PM on 22 August 2013A grand solar minimum would barely make a dent in human-caused global warming
Solar Output is Stable
Solar Output may be fairly stable at the top of the atmosphere, but solar radiation reaching the earth’s surface varies significantly. See: Wild 2009 in JoGR (http://www.leif.org/EOS/2008JD011470.pdf) and Wild 2012 in the AMS (http://journals.ametsoc.org/doi/pdf/10.1175/BAMS-D-11-00074.1).
Additionally, the uncertainty in the observations in the earth’s energy balance is significant. See: Stephens et al 2012 in Nature (http://www.nature.com/ngeo/journal/v5/n10/full/ngeo1580.html). A direct quote is:
“This lack of precise knowledge of surface energy fluxes profoundly affects our ability to understand how Earth’s climate responds to increasing concentrations of greenhouse gases.” – Graeme Stephens et al.
A quick look at Kiehl and Trenberth’s energy budget shows the surface imbalance is 0.6 +/- 17 W/m^2. Yes, that is plus/minus 17 W/m^2, which is an error bar that is 34 W/m^2 wide. The reduced IR flux from 1950 to today due to CO2 is on the order of only 1 W/m^2. The uncertainty in the earth’s surface energy balance is at least 30 times larger than the forcing effect of CO2.
Heating of the Deep Oceans
The ocean is warmed almost exclusively by short wave solar radiation. IR radiation from CO2 or the aerosphere does not, and cannot penetrate liquid water (not more than a few millimeters). Since the ocean surface is has also paused in warming, either short wave solar radiation is warming the ocean, or the deep ocean is not warming. Converting from heat content to degrees C, the ocean warming over the last 30 years is less than 0.1 degrees C, which is probably well within the error bars or the Argo float’s measurement ability.
Svensmark Gets Ocean Warming Wrong
Svensmark statement is not refuted by the NOAA Heat Content chart. Svenmark states the Argo floats have not registered any increase in temperature. The NOAA Heat Content is some output from a software model, not direct measurements like the Argo floats. Unless you can prove that Argo does show an increase in temperature, the NOAA Heat Content is a non sequitur to Svenmark’s claim.
Human Influence on Climate Change is Bigger than the Sun's
This may be true if you meant the change in the solar output at the top of the atmosphere -- since that varies by about 1 W/m^2,and the effect of CO2 is on the order of 1 W/m^2. But at the earth’s surface, the +/- 17 W/m^2 uncertainty completely swamps the effect of CO2.
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Mark Bahner at 13:05 PM on 22 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
No, I'm saying that Andrew Dessler's statement that "97% of scientists think global warming may be severe" means precisely nothing without further defining:
1) What "may" means...a 50 percent probability? 10 percent? 1 percent? 0.1 percent?
2) What "severe" means...how much global temperature rise, how much sea level rise, what will it do to global GDP, what will it do to life expectancy, and so on.
Moderator Response:[PW} Mark, you have been given incisive and complete answers to this, on this forum and in Dessler's video. It's clear you do not like the answers and are now on *extremely* thin ice, wrt to sloganeering. Further sloganeering ~will~ be removed.
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Bulletin of the Atomic Scientists: Closing the Consensus Gap
Old Mole - Quite true, quite true.
It's just that "We are that particular tiny fraction of the 3%", although accurate, isn't a very catchy slogan for denialists. It might make a good T-shirt, though.
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Old Mole at 07:29 AM on 22 August 2013Bulletin of the Atomic Scientists: Closing the Consensus Gap
I cannot personally understand why people seem so intent on attacking the 97% figure as unrealistic when clearly it is the 3% figure that really deserves scrutiny, since it really is not 3% at all, but over a dozen fractions of a percentage point combined without any real reason for doing so.
Take for example the Lu study blaming CFCs by blatant curve fitting. Do you imagine for one moment that any survey of climate scientists asked the question "Are you convinced that CFC'c are responsible for climate change?" (although that would, technically constitute AGW, since there are no naturally occuring CFCs) that over 99% of those expressing an opinion would disagree? Wouldn't that hold equally true of theories about solar fluctuation, cosmic rays, or the intervention of the Flying Spaghetti Monster?
Calling it 3% vastly inflates the credibility of AGW opponents, and hides what they really are ... cranks at the fringes of scientific thought.
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Tom Curtis at 07:23 AM on 22 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
Mark Harrigan @33, your point (1) is clearly addressed by Dessler in his video, as shown in the transcript @37. The "hole in the logic" is, it turns out, simply a matter of your not paying attention to what was said.
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Tom Curtis at 07:19 AM on 22 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
Mark Bahner @35, you are angling to suggest that Andrew Dessler does not adress the issue as to which has the greatest net cost, switching to renewable energy or maintaining business as usual. That, however, is not the case. He adresses the issue very specifically from 4:38 in the video. He says:
"There are several reasons to think that switching to renewable energy, even if climate change turns out to not be a very serious problem, is not a terribly bad action. There are co-benefits, such as cleaner air and political benefits of not using fossil fuels. In addition, its a reversible decision. If we choose not to burn coal now, we can always burn it later. And finally, it is inevitable. We're going to run out of fossil fuel, and we're going to have to make the switch; and in general the earlier you start making these changes, the cheaper they are - so starting now has that advantage.
It is also worth pointing out that climate change is, at a very fundamental level, irreversible. Every cubic kilometer of ice we loose, every centimeter of sea level rise that occurs - those are not going to be reversed on any timescale that we care about. Those are irreversible changes so far as I'm concerned. And irreversibility means that you have to be very certain of the costs and benefits before you take an irreversible action.
And so when you put all this together, it seems very clear to me that the worse error is not taking action on climate change, and having it turn out to be severe. And I think that if you want to argue that we should listen to the 3% of dissident scientists, then you have to make the argument that that is not the case - that switching to renewable energy is the worse mistake. I think that that's an extremely difficult argument to make."
I would add to that that:
1) BAU will result in a change in global means surface temperature as great as the difference between the last glacial maximum and the preindustrial average; and the assumption that such a large change can be made without major disruption of agriculture is fanciful;
2) Global warming has a high probability of completely or partially destroying major ecosystems including all arctic and subarctic ecosystems, the Amazonian rainforest, and the Great Barrier Reef (which is an almost certain casualty of ocean acidification alone, let alone the additional impacts of global warming) and the idea that humanity can swan along unharmed amidst such wide spread ecological catastrophes is again, fanciful; and
3) The most detailed economic analyses of the issue, as represented in IPCC WG 2 and 3 show the economic cost of BAU to be greater than that of taking action to prevent climate change, even though they make the absurd assumption that no matter how great the impact of climate change, it will never slow economic growth.
Thus, Dessler adresses the issue you raise and your complaint appears to boil down to that he does not do so in the same detail as WG 2 & 3 within the scope of a six minute video.
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scaddenp at 07:19 AM on 22 August 2013Andrew Dessler on Why It's Stupid not to Act on Climate Change
Mark harrigan - you argument would be better if you could cite some credible science supporting a climate sensitivity of less than 2. Hoping it will be low without also doing any kind of risk assessment for it being greater than 3 doesnt sound like sensible strategy to me. Words like "severe" or "mild" arent really that useful. Better is to look at what the projected climatic effects will be for a sensitivity of 2 and compare those impacts with costs of mitigation now.
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Tom Curtis at 06:42 AM on 22 August 2013Bulletin of the Atomic Scientists: Closing the Consensus Gap
Sphaerica @26, there is one instance in the self rated papers of a paper rated by abstract as explicitly endorsing with quantification (1) being self rated as explicitly rejecting with quantification (7), ie, a difference of -6, which is not shown on the graph. That represents the same percentage of papers as that shown for differences of -4 and 4. It is, therefore, not consequential, but should be shown for accuracy.
It is very amusing to see Joeygoze trying to suggest that the data has been hidden, when it is freely available for download.
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Bob Lacatena at 05:34 AM on 22 August 2013Bulletin of the Atomic Scientists: Closing the Consensus Gap
joeygoze,
In case you don't find it in there (although you really should read the post to which I linked -- you seem to be suffering from a lot of misconceptions based on "yeah, but what if..." thinking), the self rating data is here.
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Leland Palmer at 05:32 AM on 22 August 2013Toward Improved Discussions of Methane & Climate
Apparently, according to the IMPACTS group modeling, the sea of Okhotsk may be very important to the U.S. Their modeling shows a severe anoxic region in the northern Pacific, originating in the sea of Okhotsk, after 30 years of methane hydrate release, according to their conservative modeling. The figures in their Powerpoint slide show illustrate this anoxic region extending across to Alaska, down the west coast of Canada, and all the way down the California coast to around Baja California, wandering out into the Pacific near the equator, then continuing in diluted form along the west coast of South America.
Will there be hydrogen sulfide clouds rolling in from the Pacific into northern California within my lifetime?
A lot of that probably depends on the global methane hydrate inventory, and whether hydrate dissociation will be a top down, orderly process.
Is the real global hydrate inventory 80,000 (or more) cubic kilometers of hydrate or around 4000 cubic kilometers?
Whatever the methane hydrate inventory is, Dickens says that under projected warming conditions, the methane hydrate stability zone will shrink by about 50 percent. So, whatever is down there, maybe half of it is likely coming out, over the next decades or centuries.
Does the IMPACTS modeling take into account gas driven pumping of sea water through the hydrate deposits, for example? Wouldn't gas release into methane chimneys make the seawater in that chimney less dense, pumping upward flow? Would warm water flow down an adjacent channel, to fill that chimney? Could a sort of chaotic or oscillating flow driven by gas pumping and alternating chilling of water in adjacent channels result?
How sure are we that gas pumping will not lead to pumping of sea water through the hydrate deposits, when gas releases by the hydrate deposits increase by tens or hundreds of times?
Here's a paper that talks about very slow flow, driven by gas pumping, tidal pumping and various other forces through a normal hydrate deposit, not yet much affected by global warming:
How much will gas driven pumping increase when methane gas emission from shallow hydrate deposits increases by tens or hundreds of times?
All of this would seem to make the slab models used by the IMPACTS team at least questionable, and possibly actively misleading.
If scientific conservatism is helping to kill the biosphere, maybe it's time to try something else.
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jja at 05:29 AM on 22 August 2013How much will sea levels rise in the 21st Century?
MA Roger @37
you said, "I have yet to see anyone describe how an energy flux can be created large enough to melt enough ice for anything like 5M SLR."
You have also said (@19) that "To melt enough ice to achieve 50mm SLR p.a. would require roughly 5 ZJ p.a"1. If 11/5 of total SLR is due to thermal expansion and not ice melt (probably closer to 1/3 ) and
2. We want to find how much ice would be needed to melt to raise sea level by 5M
and we use your assumptions then
5 ZJ (ice melt) = 5 CM sea level rise, 100ZJ (ice melt) = 1 M sea level rise, Target Sea Level rise = 4 M = 400 CM = 400ZJ (ice melt)
Current Energy imbalance according to Hansen and Soto is 11.6 ZJ per year
Total Energy imbalance from today to 2100 = current energy imbalance + Increased RF between now and 2100 = (11.6 ZJ per year (corresponding to .75W/m^2) + 46.4 ZJ per year to 69.6 ZJ per year) , (corresponing increased RF from now to 2100 of between 3 to 4.5 W/M^2 additional forcing)Therefore the total energy imbalance at 2100 compared to today will be between 58ZJ per year and 81.2 ZJ per year.
These total energy imbalance values will yeild an average imbalance between now and 2100 of (approximately) 29 and 40.5 ZJ per year.
So, over an 86 year period, the total period extra energy absorbed by planet earth is between 2,494ZJ and 3,483 ZJ between now and 2100.If Atmospheric temperature is increased to +7C by 2100 and Arctic amplification due to early summer sea ice loss occurs then the deposition of 400ZJ (conservative estimate) is certainly plausible.
compare with alternative calculation below, the
The value I used was indeed RF values not energy imbalance. If I use your math and Hansen & Sotos value of .75 (they adjust for the solar minimum) I get a value of (7.5 * .75/.58) * 1.2 which is equal to 11.6 ZJ p.a. this will make a total earth cumulative energy imbalance of 1,000 ZJ by 2100 (86 years) If even a few of the non-linear feedbacks are taken into account and a higher (more realistic) emission scenario is used then the value of energy imbalance by 2100 could easily be 4-6X the current value. Therefore the total cumulative energy by 2100 will be closer to 3,000 +2,000/-1,000 ZJ . This will increase if I used the slightly higher values of Balmaseda, Trenberth & Kallen
In addition, if the ECS value is 4.3 then surface warming will be greater and the proportion of heat transferred by convection to land-based ice will increase. -
Bob Lacatena at 05:02 AM on 22 August 2013Bulletin of the Atomic Scientists: Closing the Consensus Gap
joeygoze #24,
That information is available, and in fact has already been published here, at SkS, along with the following histogram:
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NewYorkJ at 04:10 AM on 22 August 2013Bulletin of the Atomic Scientists: Closing the Consensus Gap
joeygoze,
See "Table 5. Comparison of our abstract rating to self-rating for papers that received self-ratings."
Useful would be to read the full study, the supplementary material, the FAQ, and examine the full list of papers and authors yourself, and as a learning exercise, doing your own ratings. Most of the criticism tends to be from individuals who do not have a good understanding of the study, or hope their target audience doesn't.
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joeygoze9259 at 03:22 AM on 22 August 2013Bulletin of the Atomic Scientists: Closing the Consensus Gap
NewYorkJ - So can you point me to the following data? From the article in your link.
"We invited the scientific authors to categorize their own papers, so if they responded, their 'correct' classifications of the full papers are included in our database. As illustrated in the graphic below, we found the same 97% consensus in both the abstracts-only and author self-rating methods." I see the graph below the text but it is expressed in %s, want to see the number of papers in which authors also gave a response and agree with the classification, is that available?
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