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Comments 27301 to 27350:
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sidd at 09:03 AM on 30 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
If I do the calculation for max amplitude of Rossby wave 2*sqrt(V/(2*omega*cos(phi)/a)) i get, as expected a few thousand miles. Why is this relevant ? Francis argues a different point entirely, that the jet stream has slowed and that meanders are more frequent, not that they exceed some hypothetical limit in a simplified atmosphere thats neglects topo and buncha other things. I advise those interested in these matters to read Isaac Held's most excellent blog
sidd
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uncletimrob at 08:54 AM on 30 October 20152015 SkS Weekly Digest #43
I have similar admittedly anecdotal, information about my students and what they understand. Nice to see some numbers and quotes from your students. I have to say I found this quote "Is this normal, I am a vegan and I did not know this." to be somewhat amusing but in the context of a person thinking about how they are living, quite interesting.
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Jim Eager at 07:45 AM on 30 October 2015Newest Entry in Inside Climate News’ #ExxonKnew Story is a Doozy
Hillary Clinton joins the call for an investigation:
http://thinkprogress.org/climate/2015/10/29/3717602/clinton-investigate-exxon/ -
Chuck Wiese at 07:38 AM on 30 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Moderator: I don't understand the concern in your question. The equation I provided was from published, peer reviewed and accepted literature into the atmospheric science published data base and the texbooks authors are all Phd's in atmospheric science. This material was taught in dynamic meteorology as part of my major and I don't believe any of the professors I had studied under would be so foolish as to present equations which are not valid or correct.
Textbooks for learning and lecture are not published scientific research papers as I believe you are refering to. And no, I have not seen any papers published that specifically used this equation. Does that make any difference? Every professor I know of has these texts in their own personal library and they are more commonly used as references and tools that simplify their own work and used to teach with as well. If you've never seen the equation before, does that make it wrong? The equation speaks for itself and it was derived by the authors I have given you correctly. If this paper by Vavrus and Francis is one of the first published in a climate journal that addresses Rossby wave theory, it shouldn't be a surprise that you haven't seen it elsewhere, should it?
Chuck Wiese
Meteorologist
Moderator Response:[RH] You'll forgive my personal skepticism of your lengthy explanations when you've expressed a rejection of basic greenhouse theory, vehemently rejected the work of a well established climate researcher, and failed to present any supporting research. You state here in this comment that the equation is from published research but have been unable to cite that research. If you're serious about engaging here I believe that would be a positive move toward advancing the discussion. Short of that you're merely sloganeering (which, as a moderator, is one of my primary concerns).
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Chuck Wiese at 06:32 AM on 30 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Michael Sweet, MA Rodger and Philippe: I will answer your comments in this one post.
To repeat, Jennifer Francis's conclusion in her paper and this article are wrong. You are trying to claim that just because she wrote it and it is more recent than the published and peer reviewed literature along with other recent publications, that time erases in and of itself older work. That is not how science works and any scientist with a doctorate degree knows this, and this is precisely what I have seen in many instances of work done in climate papers as they relate to atmospheric science. Assumptions are made and sometimes without bothering to look at the founding principles to see if they agree. I provided the references of this literature to show they do not and the specific equation that is used to estime a maximun Rossby wave amplitude. And as it solved from the primary equations, it is obvious that wind speed and latitude determine that amplitude with speed controlling. (And Philippe, yes, I meant EXP 1/2 to maen taking the square root of V/B.) In order for Francis and Vavrus to claim otherwise, they need to show where this realtionship is wrong, or where it was improperly derived. They have done neither. Ma Rodgers, your response is a bit more reasonable but none the less, there seems to be an attitude that older work is irrelevant if today's Phd's ignore it. That is preposterous. If Francis or Varus can show where these equations in the founding literature are wrong, then they have a valid hypothesis, but not until then and the reviewers should have caught the error in assumption.
Philippe, your post contains no citations that show how to compute the amplitute of Rossby waves or where the equation I gave is wrong. That is what is the key point in my writing to criticize, and as the moderator has asked of me, lets cut the dogpiling and "sloaganeering" . Your references not only fail to give a citation that disproves what I have provided, you are using references like the University of Oregon and calling them an "institution of superior education". What does this mean when they offer no major in atmospheric science or meteorology and have no Phd's on their staff to teach atmospheric science?
Turning briefly to the hurricanes I brought up, a few points for Michael Sweet: You are correct about hemispheres being divided at the dateline or 180 degree meridian so my bad for misstating that. But I was thinking of the body of water called the Pacific ocean that provides the fuel to both eastern Pacific hurricanes and western Pacific typhoons. Would that not be a better comparative for the puposes of climate rather than assigning an arbitrary cut-off meridian that has no climate significance?
To challenge some of your other points, I spoke by telephone this morning with Dr. Chris Landsea of the National Hurricane Center and asked about observing techniques that were used in the 1960's. To start with, he does agree the older techniques are not as good as those used today but I never said older methods were better. It is interesting to note that what they did do in those days was fly recanaissance aircraft down to 500 ft off the ocean surface under cloud bases to estimate the winds and had a US Air Force Weather Officer estimate visual conditions by a developed hurricane "beaufort scale". They also used doppler techniques as Jeff Masters mentions, but his quote from a "hurricane expert" at the time regarding the doppler technique makes no sense. The quote claims that because they were concerned about getting attenuation from flying sea spray that readings from the doppler shift would be erroneously high. The opposite would actually be true and the readings would be too low because the reference would be with respect to the true airspeed of the aircraft to get the ground speed and compute the surface winds. That is something I am quite faniliar with being an FAA licensed Airline Transport Pilot and Flight Engineer. The point in all of this is not to claim methods were better then than now, but there is no justification in claiming speeds were measured too high alone, either. There is a degree of error in any neasurement and these criticisms do not address the actual numerical significance. It would appear by these techniques they were accurate and the margin of error could be in either direction with changing circumstances.
BTW, Dr. Landsea has informed me that the National Hurricane Center is writing up Hurricane Patricia and intends on putting it into its perspective in comparing it to the record. Those of you who believe hurricane intensity is getting stronger and related to "climate change" may not like what he is going to say, but it will be up on their website soon.
Finally, I sense a lot of tension from the readers of this blog as well as a venomous dislike of any who take issue with the orthodoxy of what is written about humman induced climate change from CO2. There also seems to be a double standard on this site. The moderator is asking as do the bloggers to provide specific citations to back up claims made about a topic like this. There is nothing wrong with asking for them and I have provided them but I take note of the fact that the author of this article provides no citations for any of his claims other than a reference to Jennifer Francis at the end. Who is John Mason, what are his qualifications to write about meteorology or atmospheric science and why did the moderator accept the article without asking for specific citations of published work to back his assertions be included?
There is also a fake credential degradation used by warmers that needs to be pointed out here. Anyone who holds a bachelors degree or higher in atmospheric science is qualified for employment as a forecast or other operations meteorologist by the US National Weather Service. That is a national standard applied by the agency. It has nothing to do with "qualifying" to be a TV weathercaster. In that arena, there are no standards and plenty of scientific illiterates who know little but use the AMS TV Seal of Approval whose standards were lowerd to less than academic to claim the use of the title "meteorologist". Many of these people call themselves meteorologists but they absolutely do not meet the professional standards required for employment at the US Weather Service and that is the standard that counts. There are no licensing authorities that police the use of this title. The US Weather Service used to do it but ceased after standards were lowered to obtain a TV or Radio AMS seal. Hope this all helps.
Chuck Wiese
Meteorologist
Moderator Response:[RH] Can we assume, based on your continued lack of citations, that there is no actual published research that supports your position. (Honest question.)
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PhilippeChantreau at 01:31 AM on 30 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Chuck,
You are not addressing the problem I raised, which is that all other sources I have looked so far concur with Francis on the temperature gradient, zonal index and amplitude relationship. I provided 2 of these sources, but I looked at more and they all agreed. So your problem is not only with Francis, it is also with the University of Oregon, NOAA and numerous other institutions of superior education offering meteorology courses. Innumerable other meteorologists agree with this, and, more importantly, observations of winds aloft and temperatures are also consistent with it.
A colleague of yours, meteorologist Paul Douglas, shows some nice imagery on his blog:
http://pauldouglasweather.blogspot.com/2015/02/winter-drags-extended-march-thaw-in.html
As for the paper mentioned earlier, I seriously doubt that a meteorology paper published in Nature Geoscience wold have been reviewed by people without expertise in the field, and I find it equally dubious that the rest of the authors of the paper would have no such expertise. Seriously, how likely could that be?
Of course, there is always the possibility that they're all involved in a vast conspiracy, along with NOAA, NASA and everyone else. I guess I will have to follow my judgement of the relative probabilities of being real for each option.
Unfortunately I'm not sure that I will have the time to further investigate the matter. I hope this gets sorted out. Does your formula say exponent one half? I've tried to locate online texts with relevant formulas. It's not the easiest to write mathematical formulas on SkS.
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MA Rodger at 01:13 AM on 30 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Chuck Weise Meteorologist @50.
You kick off by conflating Francis & Vavrus (2012) with the post above which is not making your task any easier. Let us here ignore the post above.
The quote you then provide from Francis & Vavrus (2012) is, as you say, from the paper's conclusion:-
According to Rossby wave theory, a weaker flow slows the eastward wave progression and tends to follow a higher amplitude trajectory, resulting in slower moving circulation systems.
I would suggest that it is a little premature to immediately declare the whole paper in error because this quote is contrary to your own understanding of the theoretical situation. It would be prudent to at least examine the paper in its entirity. It may well be that an explanation is forthcoming. And indeed there is. A reference is provided within the body of the paper.
When zonal wind speed decreases, the large-scale Rossby waves progress more slowly from west to east, and weaker flow is also associated with higher wave amplitudes [Palmén and Newton, 1969].
So it would be pudent of you to examine Palmén, E., and C. W. Newton (1969), Atmospheric Circulation Systems, Int. Geophys. Ser., vol. 13, Academic, New York. to see what is being discussed. Yet again this matter throws up an old reference book. It appears available on-line via Researchgate which is a step too far for me. So you could be on your own in this examination.
Your point @50 that the theoretical maximum amplitude of an atmospheric Rossby wave is proportional to the square root of poleward air speed does appear to suggest a contrary relationship than the one you quote from Francis & Vavrus (2012) and such an understanding would suggest the paper makes an egregious error. But do note that it is also true this paper has been challenged since publication yet not challenged on the specific point you raise. (At least, from a limited look I have not seen such a published challenge.) This is not what we would expect if the quote were as egregiously wrong as suggested @50.
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Alexandre at 20:42 PM on 29 October 2015Leveraging the Skeptical Science Glossary for references
Neat and useful. Good idea.
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uncletimrob at 18:53 PM on 29 October 2015Leveraging the Skeptical Science Glossary for references
Thank you! A nice addition that I will alert my students to.
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Eclectic at 11:18 AM on 29 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
ChuckWiese @53 : Thank you for your further comments on Rossby Waves, but please clarify what you are saying about Francis & Vavrus ["arctic amplification . . . would do the opposite of what Francis claims"]
You have not made it quite clear whether you mean: (a) arctic amplification [as a subset of global warming] is occurring yet Francis's ideas are wrong, or (b) arctic warming is not occurring and so Francis's ideas are correct (to that extent).
Also perhaps worth mentioning what you yourself think are the atmospheric circulation consequences of the present-century's increasing areas of ice-free Polar Sea (during the overall winter/summer cycle). I presume, tentatively, that large asymmetric & irregular patches of warmer sea would have some noticeable effect on zonal & meridional air flow. But is that the case; and if so, to what extent?
I hope you will correct your earlier comments about Japan & nearby ocean being "in the western hemisphere" . . . though in the bigger picture of course it doesn't really matter how you care to divide the categories of hemispheres. It's all one world, after all. (Compare, for instance, the very well documented and devastatingly strong Typhoon Haiyan, of a couple of years back.)
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michael sweet at 10:01 AM on 29 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Chuck,
Speaking about the recent hurricane you need to check your hemispheres. Japan is in the Eastern Hemisphere, not the Western. You look stupid when you make such basic errors. Jeff Masters recently discussed the Hurricane wind speeds from the 1960's. Your discription is false. The 1960's wind speeds were estimated by eye, not with a one minute measured average. It is well known that these old wind speeds are not reliable.
Why should I believe your personal interpretation of a 1957(??) textbook when you do not even know how wind speeds were measured? Even if your ancient textbook is different from current Rossby wave science, why should anyone think that it is correct instead of current peer reviewed papers? Atmospheric Physics has advanced somewhat in the past 60 years.
This is a scientific blog. You are required to either cite current literature or substantial evidence to support your claims. The unsupported word of someone who never put in the work to earn his PhD will not get you much. You will never convince anyone that you are correct when you admit you are unable to explain the science.
Moderator Response:[PS] we are rapidly approaching dog-piling here. While I strongly agree that Chuck must provide citations rather than sloganeering, I would also ask that commentators only reply if they have a substantive response to points made. I would particularly ask that people refrain from responding to tone.
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Chuck Wiese at 09:09 AM on 29 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Sid and Phil: There is only one primary reason why atmospheric Rossby waves amplify and create large storms, severe weather and temperature extremes. It boils down to an excessively large storage of potential energy stored as the gradient of temperature across the latitude lines. The waves are then ampified by the increased incidence of baroclinity which starts the process of wave amplification through the process of cyclogenesis, which further amplifies the waves by the incipient advection of temperature which displces atmospheric mass. A storm is generated in the outflow process of this and a high pressure system is generated with a "ridge" downwind of the vertical motions and mass displacement.
These processes use the stored energy and transfer heat poleward to relax the gradient of temperature. As the created storms fill, atmospheric mass is redistributed towards its hydrostatic equilibrium and the flow degenerates back to zonal and high index, with a lessened latitudinal temperature gradient. "arctic amplification" if it were occuring would do the opposite of what Francis claims.
The only exception to the physics here is in the tropical regime where tropical storms and hurricanes develop and their energy source is the warmed waters of spring and summer that convert increased evaporation into latent heat.
Speaking of that, it is also true that the recent hurricane Patricia was not the strongest hurricane ever in the western hemisphere. It was beat by super typhoon Nancy that hit Japan in September of 1961. Aircraft recanaissance measured 215 MPH winds sustained at 1 minute before this typhoon made landafll. 172 Japanese were killed with 11,539 homes destroyed and 280,000 homes flooded from storm surge. This super typhoon held a lot of its strength together for a longer period than Patricia did, which weakened rapidly as it made landfall and caused little damage with a much smaller core of CAT 5 winds.
Chuck Wiese
Meteorologist
Moderator Response:[PS] I am sure other commentators will respond to problems with this post, but I want to request again that you cite (and preferably quote) references in support of your argument. Without those cites, your post is close to sloganeering. You have been warned already. Persisting with this line will result in deleted posts. The authority accepted here is peer-reviewed research, not claims people sign their posts with.
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mancan18 at 08:13 AM on 29 October 2015Global warming could be more devastating for the economy than we thought
ubrew12 @2
It is interesting that computer models are routinely attacked in the climate change debate, whereas when it comes to predicting economic trends to determine economic policy and microtrading shares on the stock market, computer modelling isn't questioned.
As for carbon taxes and the potential impacts associated with climate change on an economy, I would have thought that some carbon-based surcharge could be introduced that operated like the premium paid to an insurance company to insure against risk. It would be interesting to see how the actuaries working for insurance companies are modifying their tables to take into account the increased risks associated with climate change.
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sidd at 08:06 AM on 29 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
There is another paper by Francis in 2015 doi:10.1098/rsta.2014.0170 which is quite interesting. It uses self organizing maps, for one thing, which i quite like as a technique, subject to the usual caveats. But it also clearly points out that "A slower jet stream tends to take a more meandering (meridional) path as it encircles the Northern Hemisphere [13,14]. Large north–south jet-stream waves in a highly meandering flow tend to travel eastward more slowly. These waves create the high- and low-pressure systems at the surface, so their slower eastward progression increases the likelihood of persistent weather patterns that can cause a variety of extreme events [15]." The references are quite illuminating, I entertain a (probably futile) hope that some of the denialati in this thread might read them.
Moderator Response:[PS] Added link.
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Eclectic at 07:26 AM on 29 October 2015Sea level rise due to floating ice?
ECLife @57 : At a quick glance, I would say that your "discrepancy" arises from the cases being different.
You have added 1 L of fresh water onto the top of the heavy saline (and done so slowly and carefully, I presume, to allow the fresh to "float" above the saline ~ not that this is necessary: yet it does look a "prettier" experiment done that way . . . and even prettier if you add a touch of blue dye to the saline first). But the essential point is that the fresh was not displacing the saline.
OTOH, for the earlier experiment, the (fresh) ice was displacing the heavy saline : so (according to Archimedes) it was actually displacing a smaller volume [of saline] than its own (freshwater-equivalent) volume.
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ECLife at 05:54 AM on 29 October 2015Sea level rise due to floating ice?
After giving this some thought, I thought I would try a little different experiment. I made 1L of 5% salt solution (naturally there was a change in volume when adding the salt and I wasn't going for an exact salt concentration). Assuming the mass of ice to be equal to its mass of water I poured 1L of the salt solution into a 2L graduated cylinder, using a 1L graduated cylinder and using the same, rinsed graduated cylinder, I added 1L of fresh water to the 2L cylinder. Temps were the same so no thermal difference and the volume was 2L, no change. What is wrong with my thinking?
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Phil at 05:40 AM on 29 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
I realise I'm in danger of "dogpiling", but would like to highlight this point.
Chuck Wiese @50:
"Arctic amplification therefore WEAKENS, not strengthens the latitudinal gradient of temperature."
(This is in agreement with the OP)
Phillipe @40
"When temperature contrasts are very strong, the meanders are shallow in amplitude and strong weather systems (depressions) rapidly cross the Atlantic bringing wet and windy conditions to Europe. This is described as a "high" zonal index, where the contrasts between the temperate and polar zones are strong with little mixing north or south"
So the weakening temperature gradient increases the meanders in the jet stream, no ?
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Chuck Wiese at 04:51 AM on 29 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
MA Rodger and Philippe:
Here is the statement that Jennifer Francis makes in the conclusion of her paper that is clearly wrong just as this article is by John Mason that concludes high amplitude, low zonal index is the result of WEAKER latitudinal temperature gradient:
"According to Rossby wave theory, a
weaker flow slows the eastward wave progression and tends
to follow a higher amplitude trajectory, resulting in slower
moving circulation systems."
From this she concludes it is likely that severe weather and weather extremes are likely to increase around the globe because of pronounced WARMING in the arctic that is refered to as "arctic amlplification". I asked her and her co-author, Steve Vavrus, to clarify how they conclude this when the Rossby wave physics actually show that the opposite is true. Vavrus never responded and she never demonstrated where the physics of the waves were derived inciorrectly.
The amplitude of the waves is dependant on speed and latitude and for full latitude amplification, the speed MUST increase which is a function of baroclinity and increased, not decreased tempertaure gradient.
From the literature, it is determined that the maximum amplitiude of a Rossby wave is given as A = 2 (V/B ) Exp1/2, where to get the maximum, V=v or the northward component of velocity and B is beta or the Rossby parameter, given as B= 2(omega)cos( phi)/a, wherre omega is the angular velocity of the earth and phi the latitude, a the mean radius of earth.
It ought to be clear from this that amplitude is dependent on speed and latitude, with speed controlling, with the normal speed range found at the level of nondivergence and over the range of latitude that the jet streams are found. It also should be clear to any meteorologist that air accelerates moving away from high latitude at a static pressure gradient which is the main driving factor to create high amplitudes to the waves. In other words, COLD AIR ADVECTION from high latitude. Without this, Jennifer Francis's claims fall apart.
This is very fundamental atmospheric science. You say the reviewers of her work at Nature or elsewhere would have discovered such fundamental errors before allowing publication. That is absolutely not true if the authors are not trained in or understand atmospheric science. This would go right over their heads.
I have no clue as to why someone like Francis who has a Phd in atmospheric science would make suchh a fundamental mistake in her assertions. But she did and she is wrong and so in Mr. Mason who authored this article.
If you are claiming that severe weather or temperature extremes are increasing or will increase over time, then the physics of these waves demonstrate that you are supporting the claim that the earth is cooling, not warming over time, as incraesed temperature gradients across the latitudes can only be sustatined by an intensifying cold source region. The flow of heat energy is ALWAYS from warm to cold. Arctic amplification therefore WEAKENS, not strengthens the latitudinal gradient of temperature. Francis is wrong and so is the conclusion in this paper.
Chuck Wiese
Meteorologist
Moderator Response:[RH] Have you attempted to submit a comment to the journal?
Edit: Use of all caps is not allowed, per commenting policy.
2nd Edit: Repeat comment deleted.
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ubrew12 at 04:26 AM on 29 October 2015Global warming could be more devastating for the economy than we thought
Important tip when presenting this study out in the blogosphere: The classic denier slam, 'its all based on computer models' (as if computer models instantly disqualify a study's conclusions) doesn't apply to this study.
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JWRebel at 00:13 AM on 29 October 2015Global warming could be more devastating for the economy than we thought
This is huge. (moderator edited)
In terms of policy implications and instituting a carbon tax this is a really important contribution. Contrary to the oft-heard meme ("humans have always adapted", "when absolutely necessary, technology changes"), we are building up a debt which future generations will not have the wherewithal to service, since it is the capital itself (the bounty of nature) that is being destroyed and squandered.
Future losses incurred in comparison to current costs have always remained a vague discussion, even if absolutely clear in principle. This article closes the escape routes open to rhetorical rascals.
Moderator Response:[RH] Please avoid all caps.
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PhilippeChantreau at 23:37 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Chuck Wiese, re-read the quote above: " When temperature contrasts are very strong, the meanders are shallow in amplitude ." That does not support your contention, it says the opposite. I'll add that Scaddenp's suggestion of writing to the journal that published the article you find so egregiously in error is a valid one. Did you try it?
Your argument gives the impression to be from authority. Francis has a degree in meteorology that is more advanced than yours and has published on the subject in Nature Geoscience as part of a group of authors. The likelihood that she could have made such a basic mistake and that the mistake would have gone unnoticed from the rest of her team and from the Nature reviewers is so small as to be negligible. Authority would lean more to her side.
I find it strange that one would complain about the adjustments of the NASA or NOAA datasets, which are far less problematic than all the corrections applied to the satellite data. These adjustments themselves are the subject of published articles that explain what they are and why they improve the record. Furthermore, the satellite data is an indirect measurement of teperature across large vertical segnments of the atmosphere. It is plagued by far more problems than the surface temperature data and can not by any stretch of the imagination be considered more reliable, unless one is engaged in conspiratorial or other thinking divorced from reality. I also find it suspicious that one would have to select not only the time period with such constraint but also the dataset. It seems that the "static temperature" argument has a very limited domain of validity.
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MA Rodger at 21:59 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Chuck Wiese @various 32-45.
Adding to Eclectic @48, if you find some issue in the subjects raised @48 and wish to discuss them, use the approporiate thread....
...and in an appropriate manner. Concerning your input into this thread, it amounts to assertion-backed-by-insult and so far entirely lacking in any substance. If it is as you say @44 that you “have no intention of trying to educate a scientific illiterate like yourself on this subject”: if this is true then you have come to the wrong site.
It is a simple test you have to pass for this site, Chuck. Explain yourself. This is important. If you cannot explain yourself, then it is very likely you yourself do not understand what you are talking about.
Science does not operate by waving a comment and saying 'This is wrong because it contradicts the chapters that cover Rossby Waves in a couple of standard text book which are books accepted as a reference by all meteorologists!!!' And science does not operate by saying 'You are a scientific illiterate. You have no place in science.' SkS is a site that, bottom line, deals in science. Science is not like some medeaeval guild that restricts access to its secrets. So if you wish to discuss science, please act accordingly, to the best of your ability.
So far here, all we have got to is your assertion “Jennifer Francis is wrong in her paper and her assertions and so is the author of this article regarding its conclusions.. Those chapters prove it. She and those in this group have it backwards. Large waves equal large latitudinal temperature gardients and vica versa. This is basic atmospheric science and ANY unversity trained meteorologist knows about it.”
I assume you refer to Francis & Vavrus (2012). Which specific part of this paper are you asserting is wrong?
Further, it is unwise to cite chapters in a couple of books that you must know those you address will almost certainly have no access to. Do you expect all the people visiting this thread to go out and purchase copies? Because that is the only way they will be able to see what it is you are saying. If what you are attempting to establish is that well established (your reference to chapters in two books, Godske et al (1957) and Haltiner & Martin (1957) both which date to the 1950s), this piece of science must be set out in another place.
If this is not done in some manner, we may well be arguing at cross-purposes. Chuck, it is your call.
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Eclectic at 20:26 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
ChuckWiese @ #44 (and earlier) :
It would be advantageous to you, if you would read the Climate Myths section ["Argument" number 12 ] titled "CO2 lags temperature - what does it mean?" in relation to the Ice Ages. If you educate yourself on this matter, then you won't be so confused about what leads to what, in climate change. That would be a good start!
Just as importantly, examine the evidence showing overwhelmingly that global warming is continuing. [See the Myth number 5 about the so-called "Pause".] And look around you : sea-levels are faster rising, and vast amounts of ice [hundreds of cubic Kilometres annually] are melting away in this world ~ all as a result of an ongoing excess of incoming heat, year by year and decade by decade : i.e. real global warming. There may be an "18-year Pause" happening somewhere or other . . . but it's certainly not here on planet Earth.
Talk is cheap, and nonsensical verbiage even cheaper ~ so please take some time out to educate yourself on the most very basic climate matters, before you try to tackle any of the complexities.
Once you have corrected those basic errors in your earlier statements, then you can try discussing the minor details of circulation of the atmosphere. But you seem to have gotten things back-to-front . . . so, please, get the foundations right, before you start building anything higher.
Education is the key, and SKS here is an excellent website for your gaining of real knowledge on climate.
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bozzza at 20:10 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
@ 45,
Can you not see that you are propaganda itself?
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bozzza at 20:09 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
@37,
You are saying CO2 has no effect on anything, perhaps?
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Chuck Wiese at 18:06 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Tom Curtis: Your paragragh 1: OK. Not the Tom Curtis banker. Instead, "philosopher" of some sort, no real education defined and certainly none in science. How does that qualify you with respect to me? I would say you are not knowledgeable about anything in atmospheric science. Your statements reveal it. (snip)
2) I am not claiming anything with respect to Francis and myself. I am referencing her claims against established literature that she is contradicting but has not disproven. You on the other hand cannot seem to do anything more than bumble around with nonsensical rubbish that you bring Miskolczi into that he had nothing to do with in the Francis claims about Rossby waves that are wrong.
On "substantive matters"
1) The ice core records DO NOT reflect a pattern that would suggest CO2 leads temperature. And anyone who knows anything about radiation physics of the atmosphere knows that the earths hydro cycle dwarfs CO2 radaition effects and you would never expect such a result. If it were true it would be surprising and contradictory to IR radiative transfer.
2) You are rambling and bumbling on here about nothing. (snip) We are not talking about Miskolczi and a "humidity" thesis. We are talking about his calculated effects of CO2 and water vapor and how they disagree with expected global tempertaures from failed climate models. The radiosonde data is part of the record, it is not incorrect., and neither is the observed drying of the upper troposphere from modern day satellite measurements.
3) The satellite records show no discernable trend in tempertaure for 18 years of statistical significance. GISS, on the other hand along with NOAA "adjusted" long standing ocean surface temperature records and has given no valid explanation for the manipulations. It looks like the lack of warming in the satellite records was becoming an untenable embarrassment. And yes, the two records, satellite and surface are physically connected by the dry adiabatic lapse rate contrary to the fake claims they are not.
4) My descriptions of Rossby wave physics are summaries of what the authors have written. This topic is long, complex and math intensive. I have no intention of trying to educate a scientific illiterate like yourself on this subject. But I will be glad to answer questions about it if you take the initiative to study it yourself and ask questions you don't understand. I gave you the references. If you are too lazy to look them up, that is your problem, I'm not going to do it for you. I know your type, and your preconceived notions will never be open to scientific facts. You will just keep bringing up irrelevant points and make demands that are time consuming and unreasonable.
Jennifer Francis is wrong in her paper and her assertions and so is the author of this article regarding its conclusions.. Those chapters prove it. She and those in this group have it backwards. Large waves equal large latitudinal temperature gardients and vica versa. This is basic atmospheric science and ANY unversity trained meteorologist knows about it.
You demonstrate little ability to comprehend or discuss atmospheric science other than to parrot the innacurate claims made on this site and insult respectable, knowledgeable people who disagree with you and can prove you wrong.
(snip)
Chuck Wiese
Meteorologist
Moderator Response:[RH] Multiple commenting infractions.
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Eclectic at 17:23 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Mr Chuck Wiese :
What a great pity that you seem not to have encountered the SKS website before now.
If you go to the Home Page, upper left corner, you will find a listing of more than a hundred Climate Myths. Work your way through those topics there that most interest you, and you will soon find that your climate science education will be enormously improved.
In particular, you will learn how the "global temperature 18-year stasis" is a foolish fabrication by non-scientists & non-mathematicians. You may at the same time reflect on how the global sea-levels continue to rise and global ice-sheets & glaciers continue to melt ever faster in recent decades : in a manner entirely inconsistent with a "pause" in global warming.
Also, you will learn about the causal and temporal relationships between changes in atmospheric CO2 and global temperature during the recent series of glaciations.
Education is a wonderful thing, and cannot be too heartily recommended !
Your contretemps over the identity of the Skepticalscience poster Tom Curtis, is something I cannot help you with. Nevertheless, with time, you will come to appreciate & admire his scientific knowledge ~ even though he scorns to use a SpellChecker.
There are many other posters who have much scientific capability, and who may be happy to assist in your education.
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Tom Curtis at 17:18 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Chuck Wiese, former TV weatherman, (snip)
As Glenn knows quite well, I am not the Thomas Curtis employed by Deutsche Bank. Rather, I am this Tom Curtis. You will no doubt now riddle my qualifications (only a BA, and that only in philosophy), but when you do you will miss the point. The point is that by ending every communication you make on the subject of climate science with the title, "Metereorologist" you are implicitly claiming that what you say ought to be accepted based on your expertise alone. That is particularly the case given that you do not cite sources, and in this instance presented no data. Well, I am prepared to accept that some people are entitled to so ponitificate. Those people, however, are restriced exclusively to those with an extensive publication history on the topic in hand, and who are in agreement with the scientific consensus on the particular issue on which they discuss. Put another way, even the most qualifed loose their right to pontificate once the detailed topic of discussion is contentious within the scientific community.
You do not fit that category.
What is more absurd is that you are implicitly claiming that your authority as Chuck Wiese BSc, and sometime TV weatherman is superior to that of Jennifer Francis PhD in atmospheric sciences, with her thesis focussing on the Arctic, and with 40 odd recent publications on related topics. Not to mention the more then ten similarly or better qualified people who have reviewed and or discussed her thesis in the peer reviewed literature without noting the "killer argument" against it you claim to have found.
In that context, and given your implicit claim to authority, rebutting that claim does not constitute a personal attack. When you claim authority on a topic, the reality of that authority becomes relevant to disussion - and when yours is discussed it is found to be worse than non-existent.
That is demonstrate hilariously when you defend yourself against accusations of pseudoscience by apealing to Miskolczi.
On to more substantive matters:
1) The ice core record shows that rises(and falls) in CO2 generally (but not always) lags the rise(and fall) in SH temperatures, but precedes rises in NH and global temperatures. This record is consistently misrepresented by deniers who refuse to acknowledge that sometimes CO2 rises precede even SH temperatures, and insist on treating the purely regional SH temperature record as a global record. The facts as revealed by all of the data are fully consistent with a strong enhanced greenhouse effect with the initial rise in CO2 triggered by milankovitch forcing.
2) On Miskolczi's humidity thesis, even the well known AGW skeptic Roy Spencer can only bring himself to say:
"... his additional finding of a relatively constant greenhouse effect from 60 years of radiosonde data (because humidity decreases have offset CO2 increases) is indeed tantalizing. But few people believe long-term trends in radiosonde humidities. His result depends upon the reality of unusually high humidities in the 1950s and 1960s. Without those, there is no cancellation between decreasing humidity and increasing CO2 as he claims."
So, only if two thoroughly implausible spikes in water vapour from the early days of the radiosonde record, when instruments are known to have been unreliable, are not artifacts is there even a basis for the claim - but it would remain without theoretical basis of any substance.
3) The temperature trend over the last 18 years exactly, using the most recent update from GISS is 0.118 +/- 0.104 C/decade. That is, it has a statistically significant trend that distinguishes it from zero, but not from the model predictions. (Determined here, with an initial date of 1997.78) So, even the tired old, mendacious denier trick of pretending a positive trend not statistically distinguishable from zero is "a static global temperature" is now out of date. Time for you to switch to "its only because of the El Nino" while hoping we don't notice how carefully you cherry picked the last very strong El Nino for the start date of the sequence.
4) You mention two textbooks in defence of your claim, not quote no passages. Nor do you explain how their result was derived. In the meantime, Francis and Vavrus also cite a textbook in support of their views:
"When zonal wind speed decreases, the large-scale Rossby waves progress more slowly from west to east, and weaker flow is also associated with higher wave amplitudes [Palmén and Newton, 1969]. Slower progression of upper-level waves causes more persistent weather conditions that can increase the likelihood of certain types of extreme weather, such as drought, prolonged precipitation, cold spells, and heat waves. Previous studies support this idea: weaker zonal-mean, upper-level wind is associated with increased atmospheric blocking events in the northern hemisphere [Barriopedro and Garcia-Herrera, 2006] as well as with cold-air outbreaks in the western U.S. and Europe [Thompson and Wallace, 2001; Vavrus et al., 2006]."
Presumably then, at least one of you have misinterpreted your source, and your appeal to your authority as a BSc to ensure that it is not you really does not cut it, evidence wise. Particularly given your vocal history espousing pseudoscience.
Moderator Response:[RH] Let's get off the personal issues about who is who and just address the issues.
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Chuck Wiese at 16:44 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Philippe: Your statements support my contention. Low zonal index translates to high amplitude blocking and that is associated with strong latitudinal temperature gradient that transforms stored potential energy across latitude lines liberated by the exchange of cold to warm (southward) and warm to cold (northward)> If the zonal index is high, the gradients are relaxed across latitude and the amplitude decreases and wavelengths decrease to shorter waves, giving a higher N.
If the arctic is warming, the tendency MUST be towards a higher zonal index and lessened energy exhange.
There are no "modern" textbooks I have ever seen that prove Rossby physics as initially derived wrong. Just because there are more "modern" texts proves nothing if they do not demonstrate superseding old ideas with proofs. This is a major issue with "climate science". A lot of people claiming their own ideas are fact when they don't jive at all with founding principles and never disproved the foundations established in atmospheric science.
The satellite temperature records speak for themselves. With statistical methods applied, there has been no warming trend of the earth for over 18 years.
Chuck Wiese
Meteorologist
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PhilippeChantreau at 16:02 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
What I found relative to the zonal index and Rossby waves "amplitude" (the size of the meanders):
"When temperature contrasts are very strong, the meanders are shallow in amplitude and strong weather systems (depressions) rapidly cross the Atlantic bringing wet and windy conditions to Europe. This is described as a "high" zonal index, where the contrasts between the temperate and polar zones are strong with little mixing north or south. In contrast, the meanders sometimes develop very large amplitude waves which eventually break down (rather like an ox bow lake forming from an overdeveloped river meander). When this happens the "zonal index" is said to be low, and strong north-south transfers of heat take place. This results in extremes of heat waves and cold snaps depending on whether the waves are bringing your locality deep tropical or deep polar air."
Source:https://moodle.thelangton.org.uk/gip/HTMLpages/w_depres.htm
This is consistent with the OP's description. However, I note that the authors of the OP discuss the Atlantic Oscillation more than the the gradient and zonal index.
This presentation from University of Oregon shows a similar relationship between the zonal index and amplitude, or wave number, and concurs with the OP that high zonal index leads to quickly passing and generally non extreme weather systems.
homework.uoregon.edu/pub/class/atm/rossbyprimer.pdf
Blocks and extreme weather events are associated with high amplitude waves and low zonal index in all the sources I have found so far. A low zonal index is associated with lower temperature gradients.
I can say that the information I have gathered on my own so far does not corroborate this statement from Chuck Wiese above: "It is a fcat that blocking patterns as discussed here are the result of larger, not lesser temperature gradients."
I also read in the OP that indeed Arctic amplification is expected to reduce the temperature gradient and be associated with a lower zonal index. However, the behavior of the AO is also quite important.
Given the short time so far spent looking into this interesting issue, I have obviously not be able to obtain the 1957 text cited by Chuck Wiese in support of his view. However, there is considerable work and research that is much more recent than that, including meteorology textbooks, and they should certainly be considered as more up to date. The theory of Rossby waves is a bit of a challenge to confirm by observation. I found some publications by a team at University Iowa that had sevreal observations in disagreement with the theory's predictions. They did, however, qualify their results and stopped short of drawing any conclusions on the theory itself.
This statement by Chuck Wiese: "static global temperature for over 18 years and counting" needs to be substantiated. Examination with statistical methods shows otherwise. It probably should be discussed on another thread.
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TonyW at 15:56 PM on 28 October 2015Interview with Gavin Schmidt
Is there a reason for cutting off these reposts, so that we have to go to another site to read the rest? Often it's only a paragraph or so more though, this time, it was a little more substantial.
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Chuck Wiese at 14:14 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Glenn: How do you know this? He is not the head of Deutscher Bank. He is a part of their "cliamte division". It is believable I have the right person. Just look at the references and content of discussion.
If he is not this person, he reveals a shallow understanding of atmospheric science or meteorology and perhaps he would like to tell us who he is.
(snip)
Chuck Wiese
Meteorologist
Moderator Response:(RH) Who any person is or isn't is not important here. Address the issues.
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Glenn Tamblyn at 14:01 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Small problem Chuck.
Thats not the Tom Curtis you are having a conversation with!
Hard to be head of Deutscher Bank of America or any other division of Deutscher Bank when you live in Australia. -
Chuck Wiese at 13:27 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Of course not, bozzza. Your point makes the point that as the ocean temperatures rise, so does atmospheric CO2 concentration. But without a positive feedback from water vapor, the expectations from climate models fail, which they have done. We have had a static global temperature for over 18 years and counting, contrary to failed modeling in spite of rising CO2. This implies as the data does that the feedbacks are negative, which the data shows with a dryer upper troposphere.
Chuck Wiese
Meteorologist
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bozzza at 13:13 PM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
The facts are that CO2 is less soluble at higher temperatures. Does Chuck disagree with this?
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Chuck Wiese at 10:51 AM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Mr. Curtis: Your comments reflect an individual who knows little or next to nothing about meteorology or atmospheric science. As such, the only thing in your background that you seem capable of is to launch personal attacks against those who don't agree with you. (snip)
The physics of Rossby waves are well established in the published scientific literature. Those who don't get that like the comment from scaddenp and you assume I need to publish a paper to prove my assertion. That is incorrect. The opposite is actually true. It is up to the author of this article and Jennifer Francis to show where the prior established and peer reviewed literature is wrong. References of this include "Dynamic Meteorology and Weather Forecasting", authors Godske,Bergeron, Bjerknes and Bundgaard. American Meteorological Society Volume 605, 1957, Chapter 11, Hydrodynamics of the Atmosphere. With your background, you wouldn't recognize the names but the authors are famous for their work in atmospheric science. Another reference, " Dynamical and Physical Meteorology" Haltiner and Martin Chapter 12, Horizontal Frictionless Flow, 1957 ISBN 57-8005.
The physics of planetary Rossby waves are quite clear in all of this literature and point at the fact that if latitudinal tempertaure gradients decrease from arctic amplification, the amplitude of the waves and mean inflection points migrate to higher latitude and decrease. This is the opposite of what this article and Francis claim. As I said, she has offered no physics to demonstrate where the founding literature is wrong. But that is how the scientific method works. You need to prove where the established literature is in error and that has not been done.
I want to thank you for pointing out my lecture to the Oregon Chapter of the American Meteorological Society and would encourage the readers to watch it. There were also two other presenters who share my views, physicist Gordon Fulks and Climatologist George Taylor.
Your point 1 has been debunked. The ice core records prove temperature actually leads increasing CO2, not follows it. There is no demonstrated cause of CO2 affecting temperature as claimed by politicians like Al Gore. (snip)
Your point 2 is wrong. My lecture used MODTRAN and water vapor IR radiation calculations derived by Dr. Ferenc Miskolczi, a principle research scientist from NASA who specialized in IR radiative transfer. The point in doing the calculations were to show the warming of the last century far exceeded what basic IR radiation calculations would demonstrate and that there are no positive feedbacks from water vapor as claimed by warmers.
It is interesting that those like youself with no apparent science background are quick to name call those like me as "deniers" and all of the other nasty things you do, but it is also interesting to look at your background, This is from Bloomberg Business: "Mr. Thomas Curtis is the Managing Director and Global Co-Head of DB Climate Change Advisors. He has been the Global Head of Strategic Planning and Communications, Head of Business Development, and Member of Global Operating Committee at Deutsche Asset Management Inc. As Global Head of Business Development from 2004 to 2009, and prior to that, as the Head of Corporate Strategy for Deutsche Bank Americas from 2000, Mr. Curtis has been responsible for initiating and executing ...the full bio is here:
http://www.bloomberg.com/research/stocks/private/person.asp?personId=13010869&privcapId=84655488 (snip)
It would appear that you are a heavily invested special interest banker and finace person of sorts who stands to lose a lot of profit and potential income if the desired regulations and taxes imposed from carbon upon individuals fails to get traction from politicians. It also appears from your comments that you not only don't understand the fallacy of claimed "consensus" opinion on AGW, but fail to realize the concept is a ruse and a lie. There si no "consensus" on AGW like you and many other special interests claim:
http://www.climate-resistance.org/2013/07/tom-curtis-doesnt-understand-the-97-paper.html
BTW, I have more experience in opertaional meteorology than you claim. I am President of Weatherwise, Inc, and have developed a first generation brand of weather instrumentation of its kind that has predictive value:
http://www.google.com.gh/patents/US5372039
(snip)
Chuck Wiese
Meteorologist
Moderator Response:[RH] Commenting infractions almost too numerous to mention. Please read through the comments policy before making any more comments here.
Please note that posting comments here at SkS is a privilege, not a right. This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.
Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.
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Tom Curtis at 09:38 AM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Given that Chuck Wiese provides no data, or citations in support of his claims, instead relying entirely on his authority as "Chuck Wiese, Meteorologist", it is appropriate to find out what that means. It turns out it means he has a BS in Atmospheric Science from Oregon State University, and (by his claim) 25 years experience "in operational weather forecasting". According to David Appel, that experience comes down to his being a former TV weatherman.
What ever his prior experience, it is clear he is no scientist. His Jan 2012 presentation at the Oregon Chapter of the American Meteorological Association, for example, is a play book of refuted denier arguments. (As an aside, he is presented their as a "Meteorologist, Oregon State University" which would normally, and in this case falsely, suggest he had a staff position at OSU. He seems addicted to inflating his credentials by ambiguity.) My favourite section is where he 2002 - 2010 correlation of CO2 with two global temperature measures showing he is not afraid to blatantly cherry pick. This is a particularly egregious case given that:
1) We have more than a centuries worth of data on temperature and (using icecores) CO2 concentration so that there can be no need and no excuse to use a shorter period than (at minimum 1959 - present) for purposes of correlation; and
2) He knows the maths of radiative physics so that he knows annual variations in CO2 are predicted to have almost no temperature effect, even ignoring thermal inertia, so that by presenting less than a decade of temperatures for the correlation, he knowingly chose a time span over which the tempeature variation is dominated by other factors than CO2 rise (primarilly ENSO).
This episode shows that not only does he dispute the consensus position on global warming, but that he is prepared to go into full denier mode, using all the cunning and dishonest tricks that implies to defend his position.
Consequently, my view is that the opinions of Chuck Wiese, Meteorologist should be treated with a very large grain of salt, unless he backs them up in detail with cited works from the peer reviewed literature.
Speaking of which, here is a more recent review of the Francis & Vavrus hypothesis. It is amazing how none of the eleven authors thought of Wiese's objections. That may be because, as I have understood the hypothesis, Francis and Vavrus propose an increased local thermodynamic gradient due to some of the Arctic Ocean being ice covered, and some not. From that it follows that Wiese is arguing a strawman.
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scaddenp at 06:27 AM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
That is an interesting observation. The obvious response would be to submit a comment on the paper to the journal. Have you thought of doing so?
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Chuck Wiese at 03:22 AM on 28 October 2015A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
This article's conclusions consist of frivolous nonsense and and clearly wrong.
The amplitude of atmospheric Rossby waves is proportional to the speed of the jet and the speed is directly proportional to the gradient of tempertaure across the latitudes.
It is a fcat that blocking patterns as discussed here are the result of larger, not lesser temperature gradients. If the arctic was warming as cliamed, the amplitude of the waves MUST decrease and the mean inflection point of trough to ridge must do the same thing. It is impossible for the conclusions here to be correct if it is warming rapidly in the arctic. If that were true, the oppososite would occur, that is, a decrease in amplitude of the waves and a northward migration. Increased severe weather can only bec a consequence of addtional stored potential energy, not less, which tranlates to INCRESING temperature gradient, not decreasing.
I have written to Jennifer Francis about this and challenged her claims. She has never responded with any proofs of her assertions to demonstrate where the physics of Rossby waves in the published literature are wrong, which they would have to be for this article or her assertions to be correct.
Chuck Wiese
Meteorologist
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One Planet Only Forever at 00:05 AM on 28 October 2015Interview with Gavin Schmidt
Regarding the minimum Arctic Sea Ice extent, reviewing the minimimums presented by NSIDC it appears that minimum ice extent values that are noticably lower than adjacent years occur within a few years after an El Nino (The straight line trend on the NSIDC chart is a bit misleading for this evaluation. A curved line through the data points would more obviously highlight what I am referring to).
Values significantly lower than adjacent years in the minimum extent occured in the following years (with El Nino event years in brackets based on the NOAA ONI history):
- 2012 (2009/10)
- 2007 and 2005 (extended mild El Nino 2002 through 2007)
- 1999 (1997/98)
- 1995 (1991/92)
- 1990 (1986/87/88)
- 1985 (1982/83)
If this is a significant correlation between El Nino and Arctic minimum extents then a minimum below 2012 levels would be expected in 2017 or 2018.
Time will tell, but the ability of people to maintain a 'disbelief of the contantly improved understand that rapid global climate system changes are occurring with the only viable explanation for the changes being human impacts that can be reduced (contrary to developed popularity and profit interests)' appears to be diminishing at an increasing rate.
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Digby Scorgie at 17:04 PM on 27 October 2015The Brave New World of Ecomodernism
#66 KR
My question was partly rhetorical (!), but you're right, it comes down to money and infrastructure. Something like a carbon tax has to make fossil fuel expensive enough to result in its phase-out. However, I can't help thinking this is like dividing by zero: for fossil-fuel production to tend to zero, the tax has to tend to infinity. A sure-fire way of achieving decarbonization is to require fossil-fuel producers to cut their production by a mandated amount every year for a mandated period. But I can't see that happening.
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Glenn Tamblyn at 14:00 PM on 27 October 2015Climate sensitivity is low
psagar
Some points to remember. Climate response (and thus climate sensitivity) isn't just about radiative balance, heat capacity etc. Another key factor is Albedo - how reflective the Earth is.If the earth reflects the same percentage of sunlight then climate change is about radiation, heat capacity etc.
However if the Albedo is changed by climate change this in turn changes the energy balance and adds other climate change. There may be changes in cloud cover. Far more certainly there will be changes in surface reflectivity; changes in snow and ice cover, open water area, regions of desert, vegetation patterns etc. All these impact reflectivity. Warming certainly reduces snow & ice cover for example.
Importantly, many of these changes take long time periods to occur. Ice sheet changes particularly take centuries to unfold.
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Tom Curtis at 12:18 PM on 27 October 2015Climate sensitivity is low
psagar @367, first, Forcing (or Radiative Forcing) is given the following definition by the IPCC:
"Radiative forcing Radiative forcing is the change in the net, downward minus upward, radiative flux (expressed in W m–2) at the tropopause or top of atmosphere due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide or the output of the Sun."
(My emphasis)
I have quoted the full entry in the glossary below, as it contains relevant technical information plus some comments on idiosyncracies of usage.
The important point for this discussion is that radiative forcings are only those changes in TOA energy flux due to external drivers, ie, those not effected by climate variables such as (particularly) temperture and (also) precipitation, wind velocity etc; at least not on the time scale of interest. So, while a change in CO2 concentration will cause a change in radiative forcing, and changes in temperature will cause changes in TOA energy flux, changes in temperature do not cause changes in radiative forcing (by definition of radiative forcing). While this is a just a matter of definition, in my experience those who ignore the clarity given by distinguishing between radiative forcings and changes in TOA energy flux in response to feedbacks always end up making mistakes when thinking about issues of climate change.
Looking at this in more detail, we have:
ΔQ = ΔF - α ΔT (1)
where ΔQ is the change in net downward TOA energy flux, ΔF is the change in forcing, ie, the change in net downward TOA energy flux that is independent of climate states, ΔT is the change in global means surface temperature, and α is the climate feedback parameter. The climate feedback parameter is also defined in the IPCC glossary, and equation (1) is just an algebraic transformation of the mathematical definition of the climate sensitivity parameter given there. (Note, however, that the IPCC uses ΔQ for forcing, and ΔF for energy flux. I use the opposite values as it is more intuitive, and also the common practise among some climate scientists.) The units for α is in Watts m-2 oC-1, and it is the converstion factor between GMST and change in net upward TOA energy flux.
From (1), simple algebra tells us that when the GMST is at equilibrium, ie, ΔQ = 0, then
ΔF = α ΔT (2)
Equation (2) just tells us that ΔF and α ΔT have opposite intrinsic directions, ie, while ΔF reffers to net downward flux, α ΔT refers to net upward flux (as emphasized above).
Now, by definition, if ΔT equals the Transient Response to a given forcing, ΔF, then ΔF - α ΔTCR does not equal zero. If it did, the TCR would be the also be the Equilibrium Climate Response. Nor can it be greater than the ECS, for (with a positive forcing) if it were ΔF - α ΔTCR would be negative. It would follow that at some lower temperature the TOA heat flux (ΔQ) would have been equal to zero, at which point the GMST would have stopped changing, thereby preventing the temperature rising to the greater value. It follows that TCR < ECS, more or less of necessity.
So, while it is possible to construct unrealistic scenarios where TCR is approximately equal to ECS, it is literally not possible to construct one where TCR > ECS. At least, not without a fantasy physics.
Glossary Entry
"Radiative forcing Radiative forcing is the change in the net, downward minus upward, radiative flux (expressed in W m–2) at the tropopause or top of atmosphere due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide or the output of the Sun. Sometimes internal drivers are still treated as forcings even though they result from the alteration in climate, for example aerosol or greenhouse gas changes in paleoclimates. The traditional radiative forcing is computed with all tropospheric properties held fixed at their unperturbed values, and after allowing for stratospheric temperatures, if perturbed, to readjust to radiative-dynamical equilibrium. Radiative forcing is called instantaneous if no change in stratospheric temperature is accounted for. The radiative forcing once rapid adjustments are accounted for is termed the effective radiative forcing. For the purposes of this report, radiative forcing is further defined as the change relative to the year 1750 and, unless otherwise noted, refers to a global and annual average value. Radiative forcing is not to be confused with cloud radiative forcing, which describes an unrelated measure of the impact of clouds on the radiative flux at the top of the atmosphere."
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michael sweet at 12:07 PM on 27 October 2015Corals are resilient to bleaching
It strikes me as ulikely that sunscreen is harming corals in remote Hawaiian islands with no tourists, the Great Barrior reef where tourists do not go and in many other remote locations. Even if it were poisoness enough to affect corals in the ocean, which I doubt, it would only affect the most visited locations.
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Daniel Bailey at 08:58 AM on 27 October 2015Corals are resilient to bleaching
"It may not be ‘ocean acidification’ killing coral after all..."
And
"A greater threat to corals than warming and acidity may be..."
The operative phrase is "may be". Further study is required to quell the pell-mell rush down the steep path to Hyperbole land.
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Argus at 07:45 AM on 27 October 2015Corals are resilient to bleaching
"Oops! It may not be ‘ocean acidification’ killing coral after all – common chemical found in sunscreen is poisonous to coral reefs"
A greater threat to corals than warming and acidity may be suntan lotion that contains oxybenzone or any of three other ingredients. See:
Sunscreen contributing to decline of coral reefs, study shows
Moderator Response:(Rob P) There no evidence, as far as I am aware, of ocean acidification killing reef coral in the modern ocean. The decline in saturation state and the increase in hydrogen ions (falling pH) are likely making calcification, the building of coral's calcium carbonate skeleton, more difficult though.
This is because coral build their skeletons in internal chambers semi-sealed off from the ambient seawater and need to pump hydrogen ions out of the chamber in order to raise the saturation state. It permits aragonite crystals formation in this highly supersaturated environment. Lower ocean pH, as ocean acidification is currently doing, and you increase the concentration of hydrogen ions dissolved in seawater. Coral therefore have to expend more energy in pumping these ions out of the calcification chamber.It's problematic because, like many organisms, the energy budget is very tight and they can't afford to use up energy allocated to reproductive purposes. Skimp on calcification and the coral skeleton will become weaker. And there is evidence that it is indeed occurring at some locations.
But this rebuttal is about coral bleaching and subsequent mortality because the world's oceans are becoming too warm. That's the more immediate concern
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The Brave New World of Ecomodernism
Digby Scorgie - Short answer(s): money and infrastructure. Right now fossil fuels are cheaper and there is a supply and distribution network for them. Change won't happen on a large scale until there are economic reasons for it.
Case in point: Swift Fuels has developed alternative aviation gas, not to mention jet fuels, that are derived from either plant or fossil fuel feedstocks. The reason this is actually going to market is that general aviation fuel consists of 100LL, that is 'low-lead', as the 50-60 year old piston engine designs on use by GA require leaded fuel. That's an ecological nasty, and there's considerable pressure to phase the really small 100LL market out entirely - but the GA fleet will need _something_ to fly with, so Swift Fuels has an economic opportunity.
I suspect that carbon taxes and to some extent regulations that increase the cost of fossil fuels commensurate with their actual costs to the environment and health would rapidly drive a change-over to renewable synfuels for all aviation and for much of the transportation market. But until it's economically advantageous to do so, it's going to be difficult to reduce transportation use of fossil fuels.
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psagar at 02:08 AM on 27 October 2015Climate sensitivity is low
Tom Curtis @366, Thank you. "The smaller the effective heat capacity, the more rapidly will the model reach equilibrium, and the closer TCR will be to ECS." I agree that the the samller the effective heat capacity, the more rapidly will the model reach equilibrium, but I do not understand how that lead to conclude "and the closer TCR will be to ECS".
I like the definition of climate sensitivity as 'change in surface temperature per unit change in radiative forcing'. But the change in surface temperature would also cause a change in radiative forcing. So, we cannot say with certainty that ECS is higher or lower than TCS.
I clearly see that the change in surface temperature and TOA radiative forcing simulated by the model depends upon the model complexity, for example, how the ocean circulations are represented. Assuming a constant external forcing, different models would show different surface temperature change and so the climate sensitivity of different models would also be different. So I still have a thinking that ECS could be higher or lower than the TCS depending upon the complexity of the model.
Talking about real world or observations, we cannot still be certain that the TCS would be lower than ECS. For example, say we measured temperature change and radiative forcing for a decade and get a transient climate sensitivity. Now lets calculate the same for 100 years (assuming that we have the data). How can we say with certainty that one would be higher than another?
Moderator Response:[JH] Please see the SkS Glossary for the comonly accepted scientific definitions of TCS and ECS.
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michael sweet at 20:19 PM on 26 October 20152015 SkS Weekly Digest #43
I teach High School in Tampa, Florida. Every year at this time I assign a writing assignment where students read the NSIDC summary of the Arctic Sea Ice melt season (located here, scroll past the Antarctic summary). I just finished reading the reports.
I received about 53 reports from my AP Chemistry students. They are 11th and 12th graders. They are the best students in the school. This year 2 students said that they were aware of the melting sea ice situation before they wrote their report, one of those students had written the same report for me two years ago. One student who had written the report two years ago said they had never heard of the sea ice melting. (about 5 students had me two years ago).
This year only one student suggested that the melting ice is not a problem. Students may slant their reports since they know I feel strongly about the subject. 6 or 7 years ago it was much more common for students to say AGW was no problem or a hoax, at least 10% of students (unfortunately never counted). For the past three years few students say AGW is a hoax and only one or two per class strongly question AGW.
Selected comments (they are required to say something they learned):
"I learned that Global Warming is, in fact, not a myth, and that there is numerical data to support that."
"Before this I didn't really think Global Warmiing existed but now, from the data, I can see that it really does exist".
"I had no idea of the problem"
"I was very shocked to find out just how much [sea ice] had been lost over the years".
"I knew [Global Warming] was a problem, but I was unaware that it was that big of a problem ...I learned that Global Warming is not a myth, but that it is a reality affecting us now, and will continue to be a problem in the future".
"I had no prior knowledge regarding Arctic Sea Ice ... this is the first evidence of [global warmng] that I have ever really seen, and it is quite shocking".
[From this report] "I learned that decreasing ice levels can have bad effects on the Earth's environment"
"Is this normal, I am a vegan and I did not know this."
[The decrease] "suprised me, I did not think it was so drastic."
"I learned the Arctic Sea ice was melting more than most people, including me, were aware of."
Students frequently call for more research to determine if this is normal and what is the cause. They say we should do something if it turns out to be caused by humans. They are concerned this might be a problem for future generations and worry about their grandchildren. Many students this year acknowledged AGW and suggested action should be taken immediately.
I have my students do another report in January about the NOAA temperature data. That should be interesting this year. Sorry for the long post.
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Tom Curtis at 12:41 PM on 26 October 2015Climate sensitivity is low
psagar @365, the IR flux from the top of the atmosphere is a function of Global Mean Surface Temperature (GMST), not of how much heat is stored at the Earth's surface. Therefore, as a forcing is an imbalance in the Top Of Atmosphere (TOA) energy flux, to restore equilibrium with a change of forcing requires a change of GMST. No amount of change in Ocean Heat Content (OHC) by itself will have any effect on that.
Of course, change in heat content is related to change in temperature by the heat capacity. Therefore, increasing the OHC will also increase GMST. That increase, however, will continue until the TOA imbalance is eliminated, which is to say, until the change in GMST causes a change in OLR sufficient to compensate for the original forcing and any consequent changes as a result of feedback. The difference the effective heat capacity of the system makes is that the larger the capacity, the more heat must be pumped into the ocean for the same rise in GMST.
So, turning to the relationship between Transient Climate Response (TCR) and Equilibrium Climate Sensitivity (ECS). Technically the TCR is the temperature after 70 years of increasing CO2 concentration by 1% per annum (ie, at the time the CO2 concentration reaches twice the initial value). The ECS is the temperature after the CO2 is doubled and the temperature stops changing (ignoring slow feedbacks). Typically that is about 200 years after the CO2 reaches 2 times its initial concentration, although it varies from model to model depending on the effective heat capacity of the Earth's surface in the model. The smaller the effective heat capacity, the more rapidly will the model reach equilibrium, and the closer TCR will be to ECS.
In the real world, the TCR is a close approximation to the immediate temperature response to a slow forcing change. Thus we can treat the TCR is the current mean decadal temperaure divided by the current forcing and multiplied by 3.7 W/m^2 (ie, the forcing for doubled CO2). However, as the TOA energy imbalance currently is about 0.8 W/m^2, we clearly are not yet at equilibrium even though we are, by the approximation above, at the TCR for the current forcing. As closing that imbalance requires increasing GMST, it follows that ECS > TCR in real life, and not just in the models. As an aside, ECS cannot be less than TCR by virtue of the definitions of the terms, and will only equal TCR if the effective heat capacity of the Earth's surface closely approximates to zero.
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