A new meteorological season, perhaps some new science topics to discuss…
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Unforced variations: Dec 2012
I have stopped reading Superman1. Boreholing would be a service.
The problem i have with the AMEG approach is, that they do not call for emission cuts, carbon tax and biochar.
Lawrence Coleman @293
While worst-case scenarios are important, they must be based in science, and not pure fantasy. You say that 2C would lead to an additional 7 meter SLR “from alaska, canada etc.” This is not based in science.
The total amount of land-based ice left in Glaciers and Ice-caps outside Greenland and Antarctica is only about 0.15-0.37 m (see this post by Stefan Rahmstorf: http://www.realclimate.org/index.php/archives/2007/03/the-ipcc-sea-level-numbers/ ). Hence, ca 0.4 meter is clearly a worst-case scenario from Glaciers and Ice-caps.
The thermostatic component for +2C warming (compared to pre-industrial) is less than 1 meter in year 3000 (see B1 scenario in Figure 3 in Goelzer et al 2012). In year 2300 it well below 0.5 meter according to Meehl et al (2012), which finds that RCP2.6 is associated with ca 0.15-0.25 meter SLR in 2300 (RCP2.6 yields ca +2C compared to pre-industrial in 2100 and ca +1-1.5C in 2300). Even RCP4.5 is ca 0.5 meter in 2300 (RCP4.5 yields +2.5-3.5C compared to pre-industrial in 2300) (See Supplementary Table 1 in Meehl et al (2012), which is available here: http://www.nature.com/nclimate/journal/v2/n8/extref/nclimate1529-s1.pdf )
It is the great ice sheets in Greenland and Antarctica that represent the elephant in the room. And this is where the models are most inadequate…
References
Goelzer, H., Huybrechts, P., Raper, S. C. B., Loutre, M.-F., Goosse, H., & Fichefet, T. (2012). Millennial total sea-level commitments projected with the Earth system model of intermediate complexity LOVECLIM. Environmental Research Letters, 7(4), 045401. doi:10.1088/1748-9326/7/4/045401
Meehl, G. A., Hu, A., Tebaldi, C., Arblaster, J. M., Washington, W. M., Teng, H., Sanderson, B. M., et al. (2012). Relative outcomes of climate change mitigation related to global temperature versus sea-level rise. Nature Climate Change, 2(8), 576–580. doi:10.1038/nclimate1529
Just a quick follow-up thought on the Hansen et al paper I referred to above. I have been looking forward to this paper and others in the forthcoming issue of Philosophical Transactions of the Royal Society A, based on presentations on a seminar on “Warm climates of the past – a lesson for the future?” at the Royal Society in October, 2011.
James Hansen’s talk, together with all the others, are available as mp3:s here: http://royalsociety.org/events/2011/warm-climates/
Unfortunately, there are no powerpoint slides to go with the audio, but I guess that the previously mentioned paper by Hansen contains similar images that he discusses in his talk.
Thanks for the reference to the new Hansen paper. I see that they use a model by Russell et al. simplified to have an ocean depth of 100m, resulting in halving of oceanic poleward transport. This is done to reduce equilibration times. I am reading the Russell paper now, I see that the original model has more realistic deep ocean. Mention is made of a forthcoming paper by Russell which I look forward to. Another simplification is that the ice sheets have no internal dynamics, rather are surface properties of tundra. So I wonder if all essential physics is indeed included, or something dangerous has been left out.
These quibbles aside, I like it ! Agree with the call for better paleo data.
sidd
Prokaryotes #302,
“302.The problem i have with the AMEG approach is, that they do not call for emission cuts, carbon tax and biochar.”
That’s true, but I think you have to address the ‘why’ as well as the ‘what’. There appear to be two reasons: one stated, one implied. On p.10 of the Strategic Plan, it is stated: “There is one thing that we do know can produce an appropriate amount of cooling power: the sulphate aerosol in the troposphere, as emitted from coal-fired power stations and from ship bunker fuel. This aerosol has offset CO2 warming by around 75% in the past century. There should be a temporary suspension of initiatives and regulations to suppress these emissions, while they are having a significant cooling effect in the Northern Hemisphere, unless human health is at risk.” I had a double-take when I first read this, but it does appear that they are promoting continuing certain types of fossil fuel combustion because of the cooling power of their sulphate aerosols.
The implied reason is the predicament in which they find themselves. They truly believe there is a near-term problem in the Arctic that will prove irreversible unless addressed in the relatively near future. They also look at the world as it is, and see essentially no prospect for any real CO2 emissions reduction in the near or intermediate future. So, what are their options given the three-legged stool of technical/economic/sociopolitical that I defined in #297? Well, they can do nothing, and they see that as leading to near-term disaster. Or, they can propose some high-tech option that keeps the economy going and keeps people employed, as something that might be acceptable to the public.
Would it address the underlying problem, as would the ‘emission cuts, carbon tax and biochar’ you suggest, and other similar options? Obviously not! But, it seems to me they are really saying the only thing that would ‘sell’ is some near-term politically acceptable band-aid that gave us time to address the more fundamental problem. I also view their three proposals as ‘straw-men’. They need something tangible to bring to the table, and this is what they have generated. These proposals could serve as a starting point for more serious discussions, and hopefully the technical (and maybe even political) community could provide value-added with more serious enhancements. I think they’re really trying to get some action going at this point.
Oh, i did not even knew this, lol – this is a bit nuts to try fire with fire.
Sulfur dioxide (SO2) aerosols in the atmosphere are due mainly to increasing volcanic activity not from burning coal, according to NASA. Sulfur dioxide aerosols have a cooling effect and have recently been blamed for “hiding global warming.” http://tucsoncitizen.com/wryheat/2011/07/18/nasa-says-volcanoes-not-coal-burning-is-major-source-of-sulfur-dioxide-in-atmosphere/
The good thing about AMEG seems to me that they bring up the topic of Arctic Methane, but to opt for more coal and more aerosol spraying will not work. This is just to complex, with all the storms, precipitation patterns, methane from wetlands a current major player for methane uptake.
The first step for any action is to enact the Carbon Tax – NOW! Then we need Biochar, Subsidies for clean tech, batteries …
Supe…1, that dead horse was pretty well beaten last summer.
Try http://www.realclimate.org/index.php/archives/2012/06/methane-game-upgrade/ re AMEG and EPA on sulfate regulations. Coincidental?
Boring.
Carbon held in fossil fuel companies’ reserves. (Courtesy of Carbon Visuals)
That’s on the main page of today’s http://www.washingtonpost.com/
And ReCaptcha continues to win the Turing Test with
“least tToBad”
Hear, hear. Tolerance seems to be causing positive feedback. What’s the threshold for a quorum?
Starvation Didn’t Wipe Out Sabertooth Cats
http://www.livescience.com/25848-starvation-extinction-sabertooth-cats.html
I’ll take this as more evidence for the Clovis Comet.
AMEG Cooling techniques: I also cannot see this happening on a voluntary basis having seen a bit of the international legalities involved. There will be winners and losers, will the winners be able to compensate the losers adequately and by what means. People in Africa and India can’t eat money. The understanding of the physical processes in trying to manipulate climate on a subglobal scale, specific to a particular area or region will require complete understanding to even the smallest micro level. We are still struggling to understand the macro processes. So I also think forced implementation may unfortunately be the only way. Who does the forcing? By dictatorship or committee?. I believe that geoengineering of the climate will only happen when it truly positively HAS to happen and that will of course be far too late.
perwis: The total contribution by the arctic/antarctic regions is in the ball park of 21m sea level rise. Assuming a complete melt. I did say 2 millenia although I feel this length of time is way too optimistic. Kevin Anderson believes that from 0.8-2C will be sufficient. Don’t forget the poles are already experiencing a 4C increase and this rate is accelerating. It’s hard to base this on science when the science isn’t out yet and we are in uncharted territory unless you go back to the last interglacial period, but the mechanics then were not the same as now. There was far more flora (e.g rainforest) to soak up CO2. If you believe the IPCC arctica will be ice free in summer in 30+ years..should we believe that science??
James Hansen and Makiko Sato
Update of Greenland Ice Sheet Mass Loss: Exponential?
26 December 2012 http://www.columbia.edu/~jeh1/mailings/2012/20121226_GreenlandIceSheetUpdate.pdf
Hate to say this, but Hansen is doing numerology on GRIS projection. If he wants to expand this into a paper with ice dynamics i might take him more seriously.
sidd
290 Superman1 said, “a [written] debate, or some sort of exchange, among three experts”
You aren’t getting the results you desire (I’m assuming) because you’re not picking venues appropriately. Though 290 is on topic and appropriate, I’m sure you were here for the discussion on Climate Dialogue’s first written debate amongst three experts, so…
Did you submit your idea for a topic to Climate Dialogue first, and are submitting it here as a back-up?
-OR-
Did you feel that Real Climate would be a better place for such a thing? If so, why?
298 Superman1 asks, “However, clouds serve their own purposes, and arbitrarily removing them might have its own set of unintended consequences. Can we model this situation with sufficient accuracy to be confident we are not making the problem worse?”
Your wording makes it sound like something with lasting consequences. Most GE projects are nearly instant-on and instant-off. I assume the timing for such an experiment would be to coincide with a big world surplus of food. Lots of safeguards and conditions ensuring any damage is minimal. Truly, can you imagine it not being so? Such a project would get more scrutiny than anything anytime anywhere. The risk, other than to the individuals in Region A who are harmed and those in Region B who benefit (when they’d swap destinies without the GE experiment), is primarily that the effort will have been wasted. Any harm beyond that is easily prevented simply by stopping the project.
OTOH, it could be said that GE’s primary harm is psychological. If we can pretend that we can get away with burning everything, then many votes will be cast to do exactly that.
Jim Larsen #316,
First time I’ve heard of Climate Dialogue. What is it?
I’m indifferent to venue. If it were posted on Climate Progress, fine. I thought the debaters would be more amenable to Real Climate because of the scientific credibility of the monitors. In any case, we need the challenges to these somewhat different assertions about where we are relative to reversibility. I’m tired of reading these papers and hearing these videos where assertions go unchallenged.
Jim Larsen #317,
“I assume the timing for such an experiment would be to coincide with a big world surplus of food. Lots of safeguards and conditions ensuring any damage is minimal. Truly, can you imagine it not being so?”
I can only go by what the AMEG proposers state in their Strategic Plan: “The situation is so urgent that, unless appropriate action is taken within a few months, the window of opportunity will be lost.” That has little to do with the forerunner research, development, and testing that I’m used to before deploying such a complex system.
The Plan states further: “The target should be to prevent a new record low of sea ice extent next year (2013). This involves providing sufficient cooling power into the Arctic to offset the warming which has built up as the sea ice has retreated.” Basically, they want to cool the Arctic. Given the heat influx laterally from both the warm atmosphere and ocean, which no doubt accelerated the melting the past few years, large regions would have to be cooled. The scale of the solution has to match the scale of the problem!
I don’t view this as a small perturbation. Where are the models that can handle the very small physical points of injection and allow regional compatibility with global compatibility? I would suspect such models would take years to develop before they were tested and passed for reliability. The proposers want to deploy the system in months! This makes a Hail Mary pass look conservative!
However, this proposal does give us an opportunity to do something constructive, rather than assemble another circular firing squad. One way to generate potential innovation is to start with some concept, identify the good and bad features, eliminate the bad ones, then build on the good ones. If enough people contribute to this process, sometimes really good ideas can result. We have a proposal on the table from AMEG; what are the positive and negative features? What needs to be eliminated; what needs to be added? Prokaryotes started to do this in #307. How can we expand this further?
Supe…1
318 Superman1,
Cool. Perhaps you’d enjoy the RealClimate discussion on ClimateDialogue’s first debate, which was on arctic sea ice and included Walt Meier, Judith Curry, and Ron Lindsay. It’s an interesting discussion with lots of good thoughts and ideas on how ClimateDialogue might fine-tune their process.
http://www.climatedialogue.org/
http://www.realclimate.org/index.php/archives/2012/11/climatedialogue-exploring-different-views-on-climate-change/
319 Superman1 said, “I can only go by what the AMEG proposers state in their Strategic Plan: “The situation is so urgent that, unless appropriate action is taken within a few months, the window of opportunity will be lost.” ”
We know that arctic ice recovers easily when conditions are appropriate. Sea ice has no tipping point and little memory. Sea ice’s “window of opportunity” could be as wide as when winter sea ice still forms. That’s a mighty wide window.
We also know permafrost and clathrates are well-protected. Like an adobe house which stays cool through a hot day, it takes a long time for a pulse of warmth to reach permafrost. 2013′s heat will be clathrate-felt decades from now as a tiny blip it almost notices.
It’s a tipping point, but the time scale is geologic. Plus, buried ice melts at different rates at different depths and surface conditions. Add in chimneys et al and the signal is blurred like crazy, like a zillion little carbon valves each doing its own thing.
From our viewpoint, it’s a long slow slide that gets ever steeper. The further along you get, the more extreme GE you’d have to do if you want to restore a semblance of initial conditions. This is especially true since whatever you do will be delayed in action. GE can restore sea ice quickly, but there’s absolutely nothing we can do about the delayed heat we’ve sent down towards the buried ice.
So what if we miss the deadline and the plan slips a year? I didn’t read the proposal and would guess the principals don’t paint the ramifications as bleak as you seem to propose – that the fate of the world hangs on what we do in the next few months. Hmm, care to buy my slightly used Mayan calendar?
Jim Larsen #321/Hank Roberts #320,
Thank you for pointing me towards Climate Dialogue. When I saw Bart’s name, I remembered the thread about his venture. In fact, I had a couple of comments on that thread.
I have read the official remarks of the three invited presenters, and some of their responses to public comments. I suspect my views on what you call an ‘interesting discussion’ differ from yours.
There are three metrics of interest in evaluating the Climate Dialogue discussion: choice of topic; selection of presenters/discussants; motives of monitors/sponsors. The central issue/topic of interest has three major components: does global warming/climate change exist; if so, what fraction is attributable to anthropogenic forcing; what can we expect if present trends continue. Why did the flagship discussion not address this central problem? Arctic ice cap loss is a potential symptom of climate change. There are many other symptoms that could have been selected, such as Greenland ice loss, Antarctic ice loss, floods/storms in Europe, droughts in SW, two hurricanes in NY in two years, etc? But, why would one select a symptom, rather than the problem and its causes?
In the medical world, a disease is characterized by many symptoms. One would not think of focusing on a specific symptom in analyzing a disease. Rather, one focuses on a ‘signature’ of symptoms to characterize a disease, that unique weighted pattern of symptoms reflective of the disease. One tracks the ‘signature’, not merely any specific symptom.
Climate change is characterized by the increased frequency and magnitude of what were once considered ‘extreme’ events. We have had hurricanes stronger than Sandy hit the NY/NJ area. Sandy was a Cat 1; I remember a hurricane in 1944 that demolished Heinz’s Pier in Atlantic City. We have had droughts in the SouthWest before; the dustbowl in the 30s. We have had extreme heat waves before. What makes these events unique to climate change is their increasing frequency and magnitude. Once in a century storms are occurring once on a decade or sooner. That should have been the focus of the flagship issue, but instead, a symptom, with its higher variability, was chosen for the focus.
All the presenters were funded by the USA government. If they had been funded by e.g. the Koch Bros., there would have been a hue and cry about selective bias. Why; because grantees/contractors/employees tend to promote the views with which their sponsors are comfortable. And, the somewhat similar conclusions the presenters reached were those with which the climate change action-free USA government would be very comfortable. ‘Yes, there might be a problem, but we have time, and we really need more research.’ For any credibility, there should have been two, or preferably three, different funding sources, including one or more McPherson types with no external funding.
Finally, the motives of the monitors. They were selected by the Dutch government to perform a task. I know very well how the USA government selects such people to head panels or workshops: good scientists, but sufficiently reliable to produce the results that protect the government. I doubt the Dutch government uses different criteria. And, it worked. The result would put a gleam in the eye of any government that wanted to justify its inactivity on climate change, and delay its actions far into the future.
Sidd @315
Regarding Hansen & Sato’s note (link in @314 above): The fitting of exponential curves against the recent data of ice sheet mass loss found in Sheperd et al (2012) is a simplistic approach, and perhaps not sufficiently justified. However, they also suggest some arguments for non-linear mechanisms that could come into play (these are found in the Appendix of the note, which is an excerpt from Hansen & Sato 2012).
Hansen & Sato provides at least five arguments in favour of exponential ice sheet loss:
1. BAU scenarios have a “climate forcing that is increasing at a rate dwarfing any known natural forcing”. (p. 4)
One implication being that historical maximum glacier speeds during recent times (e.g. the methodology used by Pfeffer et al 2008) are not necessarily indicative for the maximum speeds at the end of the century. Sounds plausible to me.
2. “As warming increases, the number of ice streams contributing to mass loss will increase, contributing to a nonlinear response that should be approximated better by an exponential than by a linear fit.” (p. 4)
It seems plausible that more ice streams in the great ice sheets will be activated in a warming climate, and the contribution will therefore be more than linear.
3. “Some Greenland ice stream outlets are in valleys with bedrock below sea level. As the terminus of an ice stream retreats inland, glacier sidewalls can collapse, creating a wider pathway for disgorging ice.” (p. 4)
This also sounds plausible. For example, the Jakobshavn Isbrae has a deep trough more than 1000 meter below sea level stretching more than 60 km into the ice sheet, the Pine Island Glacier has a trough more than 250 km (Thomas et al 2011). I have not seen any modelling that takes into account the effect that Hansen & Sato describes. Perhaps someone can point me to such studies?
4. In Antarctica, “large portions of the ice sheet are buttressed by ice shelves that are unlikely to survive BAU climate scenarios” (p. 5).
The removal of ice shelve buttressing gives a highly non-linear acceleration. For example, the recent acceleration of the Pine Island Glacier looks exponential (see Figure 2 (d) in Thomas et al 2011), and the modelled acceleration after an ice-shelf breakup is even greater (see Figure 4 in Thomas et al).
5. Most of the West Antarctic Ice Sheet and large part of the East Antarctic Ice Sheet are grounded below sea level (corresponding to about 20-25 meter of SLR), making it vulnerable to rapid collapses.
These are four strong arguments, at least prima facie, for assuming a supra-linear contribution from the great ice sheets in Greenland and Antarctica. Will it be exponential during the course of the 21th century and with what exponent? This is hard to say, but Hansen & Sato’s arguments at least provide reasons to seriously investigate the possibility of greater than linear acceleration of SLR.
This is in stark contrast with the prevailing approaches to SLR projections, which seems to be based mainly on linear assumptions.
For example, the IPCC AR4 calculations of ice-sheet dynamics, which Alley et al (2008) calls “back-of-the-envelope approaches” are based on the assumption that if “ice-flow ‘contribution were to grow linearly with global average temperature change’, an additional 0.1-0.2 m of sea-level rise would result” (p. 1061).
Another example is Rignot et al (2011), which gives yet another linear extrapolation and finds that “At the current rate of acceleration in ice sheet loss, starting at 500 Gt/yr in 2008 and increasing at 36.5 Gt/yr2, the contribution of ice sheets alone scales up to 56 cm by 2100.”
If anything, I am sceptical of the dominant linear extrapolations of ice sheet dynamics, which may perhaps be due to “scientific reticence” (Hansen 2007) or “Erring on the side of least drama” (Brysse et al 2012)…
(List of not obvious) References:
Alley, R. B., Fahnestock, M. & Joughin, I. (2008). Supporting Online Material for Climate change. Understanding glacier flow in changing times. Science, 322(5904), 1061–2. doi:10.1126/science.1166366
Brysse, K., Oreskes, N., O’Reilly, J., & Oppenheimer, M. (2012). Climate change prediction: Erring on the side of least drama? Global Environmental Change. doi:10.1016/j.gloenvcha.2012.10.008
Hansen, J. E. (2007). Scientific reticence and sea level rise. Environmental Research Letters, 2(2), 024002. doi:10.1088/1748-9326/2/2/024002
Rignot, E., Velicogna, I., Van den Broeke, M. R., Monaghan, a., & Lenaerts, J. (2011). Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise. Geophysical Research Letters, 38(5), 1–5. doi:10.1029/2011GL046583
Thomas, R., Frederick, E., Krabill, W., Manizade, S., & Martin, C. (2009). Recent changes on Greenland outlet glaciers. Journal of Glaciology, 55(189), 16.
This is the dawning of the Age of Arrhenius.
30078232888
Perwis @324
In addition to the non-linear factors you mention, isn’t it also true that the flow viscosity of glacial ice would decrease with rising temperature in the ice? Or is this small enough to be neglected?
Re Jim Larsen: Sea ice does and can bounce back if it’s only due to favourable weather conditions on the surface but what about the melting from below? When the surface waters are consistantly at 0C or higher how can ice form? That to me that constitutes a tipping point. Even during the arctic winter the warm currents from the south are mixing with the cold.
Superman: I’m getting a little bored with Jim Hansen’s famous dice analogy which he drags out every interview but it does plainly illustrate the change in climate over the past 40-60 years. Before- post CC the dice had one side blue (below average temp) one side red (above ave. temp) and 4 sides white (usual temps). Now in 2012 it’s 4.5 sides red, 1 side white and 0.5 sides blue..(these are taken from global climatic events) quite a change in 40 years! You should see the bell curve..it’s unrecognisable.
Re, perwis: “Some Greenland ice stream outlets are in valleys with bedrock below sea level. As the terminus of an ice stream retreats inland, glacier sidewalls can collapse, creating a wider pathway for disgorging ice.”
I find this interesting in regards to ice flow…
Flow of Ice Across Antarctica http://www.youtube.com/watch?v=-8iWelvcd9U
Mr. perwis: There seems to be some confusion here.
1)By exponential i mean the sea level height h=h0*exp(t/tau) where tau is the time constant. Hansen exhibits two exponential projections with 5 and 10 yr doubling time. (tau is simply related to the doubling time). These are not better fits than the linear fit as Hansen himself says.
2)by supralinear i mean any polynomial increase above first order:
h=h(i)*t^i, summed over i, where at least one h(i) is nonzero for i>1
3)I see no current data supporting exponential rise in sea level contribution from GRIS, or WAIS. I do see data supporting supralinear rise.
4)Hansen himself warns that exponential rise in sea level contribution cannot persist, will be self limiting.
5)The reasons 1)-4) you mention all plausibly support supralinear rise. But a calculation must be done explicitly including these effects. Curve fitting is of no avail without physics. So I think Gregoire is a much better treatment than this GRIS projection from Hansen.In short, put in the ice dynamics like Gregoire and the climate models like Tedesco, shut up and calculate. Hansen is not lacking in wits or resource. He can do much better than curve fitting, that’s why I find his note disappointing.
6)(personal opinion) I am beginning to think, in light of the Tedesco treatment, that SMB will be as large a contribution to GRIS mass waste as calving and submarine melt. And of course it might rain on GRIS. But in the case of WAIS, not so. For example PIG is 40 Km wide compared to JI at 4Km and Thwaites is wider, the submarine exposure to warm ocean is an order of magnitude larger, and air temperature increase is is not nearly as large as on GRIS. So WAIS will melt from below.
sidd
On the first day of Christmas (I meant to have this done a few days ago) my search engine gave to me…
Atmospheric circulation and climate change, focus on Earth, AGW, extratropical storm tracks and extratropics in general, but with exceptions
I. mostly Science articles directly addressing such matters
II. background info and resources
-A. textbooks and websites, general, including some Earth/Planetary system stuff (for comparison)
-B. some more atmospheric/oceanic dynamics textbooks and websites
-C. a series of mostly peer-reviewed articles, and a few websites, roughly organized by topic (PS ‘THM93′ and the ‘CPRW’(1-4,maybe 5) papers will not be elaborated on much here; they will get more attention in part III)
III. my own attempt at a brief introduction that will help in understanding the above (I will take a break after I and II before getting to this).
In quotes, unless stated otherwise, emphasis is mine.
Most of these (in I. and II.) I have only skimmed or read the abstract and/or looked at the graphs (so don’t assume that a lack of tag or (signalling that climate change is addressed somewhere somehow) means I wouldn’t have recommended it or … etc. – also, I had a particular set of interests (extratropical storm tracks, wave propagation, synoptic and planetary scale dynamics) and goals (articles that can be used to introduce oneself to a topic, and/or that provide mechanistic explanations) and choices to ‘recommended’ reflect that. Also I probably haven’t been consistent in applying it so take it with a grain of salt – for example, in part I). I will probably never read through it all, but I have read through some and plan to read through some more. But I wanted to get this list together and post it sooner rather than later or never.
Here’s part I:…
especially recommended (also apply to a few at the beginning where I didn’t specifically say so?)
CLIMATE CHANGE – AND CIRCULATION (FOCUS ON MIDLATITUDE STORM TRACKS, with one or more? exceptions)
Especially recommended!
climate change – and background information
**
Allison Wing, 12/11/09: Extratropical Storm Tracks.
http://web.mit.edu/awing/www/stormtracks.pdf
(climate change pp. 9-10, 11-12, and starting again (I think) on p.14;
p.12: “O’Gorman and Schneider (2008) found that the eddy kinetic energy scales linearly with the mean available potential energy and that the mean available potential energy depended on the vertically integrated meridional temperature gradient. McCabe et al. (2001) and Yin (2005) also noted that the higher tropopause would mean a deeper baroclinic zone and that some system could utilize this increased supply of available potential energy aloft.” – just one of the points brought up.
also, p.12: increased H2O vapor leads to increased latent heat release, which may make extratropical storms stronger, but increased H2O vapor can/could increase horizontal latent heat flux, making storms more effective in poleward heat transport, tending to decrease number and/or strength/size? (“smaller“) of eddies.)
***
Bengtsson, Lennart, Kevin I. Hodges, Erich Roeckner, 2006: Storm Tracks and Climate Change. Journal of Climate, 19, 3518-3543.
http://journals.ametsoc.org/doi/pdf/10.1175/JCLI3815.1
(from the abstract: “The statistical distribution of storm intensities is virtually preserved under climate change using the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A1B scenario until the end of this century.“; did not find more intense storms (tropical or extratropical); find a “minor reduction” in the number of weaker storms; significant regional changes; poleward shift, more clearly in Southern Hemisphere – Southern Hemisphere storm track shifts “associated with zonal SST gradient” changes “in particular” the Southern Hemisphere.)
(nice maps)
***
Bengtsson, Lennart, Kevin I. Hodges, Noel Keenlyside, 2009: Will Extratropical Storms Intensify in a Warmer Climate? Journal of Climate, 22, 2276-2301.
http://journals.ametsoc.org/doi/pdf/10.1175/2008JCLI2678.1
(end of abstract:
interesting figures!)
***
Paul A. O’Gorman, 2010: Understanding the varied response of the extratropical storm tracks to climate change. PNAS 2010 ; published ahead of print October 25, 2010, doi:10.1073/pnas.1011547107
http://www.pnas.org/content/early/2010/10/18/1011547107
http://www.pnas.org/content/early/2010/10/18/1011547107.full.pdf+html
(part of abstract:
)
———–
***
Francis, J. A. and S. J. Vavrus (2012), Evidence linking Arctic amplification to extreme weather in mid-latitudes, Geophys. Res. Lett., 39, L06801, doi:10.1029/2012GL051000.
http://www.agu.org/pubs/crossref/2012/2012GL051000.shtml
http://www.vliz.be/imisdocs/publications/234818.pdf
(was discussed here previously (16, 69-70, 75, see also 20 and 208-212 @ http://www.realclimate.org/index.php/archives/2012/11/unforced-variations-nov-2012/comment-page-1/#comments )
I’ve seen (the links for) a couple of related youtube videos in comments at RC before; I’m not sure if these are the exact same ones:
16:04 Does Arctic Amplification Fuel Extreme Weather in Mid-Latitudes?
http://www.youtube.com/watch?v=4spEuh8vswE
1:24:25 Weather and Climate Summit – Day 5, Jennifer Francis
http://www.youtube.com/watch?v=RtRvcXUIyZg
———–
especially recommended (the next several)
Rivière, Gwendal, 2011: A Dynamical Interpretation of the Poleward Shift of the Jet Streams in Global Warming Scenarios. J. Atmos. Sci., 68, 1253–1272.
doi: http://dx.doi.org/10.1175/2011JAS3641.1
http://journals.ametsoc.org/doi/abs/10.1175/2011JAS3641.1
abstract
———-
***
Barnes, E.A., and D.L. Hartmann, 2011: Rossby Wave Scales, propagation and the variability of eddy-driven jets, J. Atmos. Sci. , 68, 2893-2908.
http://www.atmos.washington.edu/~dennis/Barnes&Hartmann_Scales2011.pdf
(
see also? Barnes Hartmann 2012 The Global Distribution of Atmospheric Eddy Length Scales
related?? – Fyfe Lorenz 2005 Characterizing Midlatitude Jet Variability: Lessons from a Simple GCM)
***
Barnes, E.A., and D.L. Hartmann, 2012: The Global Distribution of Atmospheric Eddy Length Scales. Journal of Climate, 25, 3409-3416.
DOI: 10.1175/JCLI-D-11-00331.1
http://barnes.atmos.colostate.edu/FILES/MANUSCRIPTS/Barnes_Hartmann_2012_JCLI.pdf
(in press version:
Barnes, E.A., and D.L. Hartmann, 2012: The Global Distribution of Atmospheric Eddy Length Scales. J. Atmos. Sci. , , in press.
http://www.atmos.washington.edu/~dennis/Barnes_Hartmann_2011_JCLI_scale_subII.pdf )
immediately after abstract:
———-
***
Barnes, E.A., D.L. Hartmann, D.M.W. Frierson, and J. Kidston, 2010: The effect of latitude on the persistence of eddy-driven jets. Geophys. Res. Lett., 37, L11804, doi.10.1029/2010GL043199.
http://www.atmos.washington.edu/~dennis/Barnes_etal_2010GL043199.pdf
(see eq. 3 p.3/5)
***
Barnes, E.A., and D.L. Hartmann, 2010: Testing a theory for the effect of latitude on the persistence of eddy-driven jets using CMIP3 simulations. Geophys. Res. Lett., 37, L15801, doi:10.1029/2010GL044144.
http://www.atmos.washington.edu/~dennis/Barnes&Hartmann2010c.pdf
(focusing on Southern Hemisphere; from abstract: Earth’s sphericity inhibits wave breaking on poleward side of jet, decreasing wave-mean flow feedback, widens the jet and makes the jet less “self-sustaining”; SAM is less persistent when jet is shifted poleward, and models with jets at too-low latitudes may exaggerate poleward shift in response to global warming.)
***
Barnes, E. A. and D. L. Hartmann (2012), Detection of Rossby wave breaking and its response to shifts of the midlatitude jet with climate change, J. Geophys. Res., 117, D09117, doi:10.1029/2012JD017469.
http://www.agu.org/pubs/crossref/2012/2012JD017469.shtml
(in press form: http://www.atmos.washington.edu/~dennis/Barnes_Hartmann_2012_JGR.pdf )
(changes in anticyclonic and cyclonic wavebreaking associated with climate change and poleward jet shift in the Southern Hemisphere:
abstract:
offhand, I don’t know if the cyclonic and anticyclonic wave breaking events mentioned are generally poleward or if there are any equatorward breaking events as well…)
———-
***
Zelinka, M.D. and D.L. Hartmann, 2012: Climate Feedbacks and their Implications for Poleward Energy Flux Changes in a Warming Climate, J. Climate , 25, 608-624.
http://www.atmos.washington.edu/~dennis/Zelinka&Hartmann_2012.pdf
(see also (both below in the H2O section):
Muller and O’Gorman 2011
Held and Soden 2006 )
——–
especially recommended
*
Graff, Lise Seland, J. H. LaCasce, 2012: Changes in the Extratropical Storm Tracks in Response to Changes in SST in an AGCM. J. Climate, 25, 1854–1870.
doi: http://dx.doi.org/10.1175/JCLI-D-11-00174.1
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00174.1?journalCode=clim
(
)
especially recommended (includes STRATOSPHERE)
**
Butler, Amy H., David W. J. Thompson, Ross Heikes, 2010: The Steady-State Atmospheric Circulation Response to Climate Change–like Thermal Forcings in a Simple General Circulation Model. J. Climate, 23, 3474–3496.
doi: http://dx.doi.org/10.1175/2010JCLI3228.1
http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3228.1?journalCode=clim
http://www.atmos.colostate.edu/ao/ThompsonPapers/Butleretal_JClimate2010.pdf
(abstract:
tropical troposphere warming: poleward shift in extratropical storm tracks; weaker stratospheric Brewer-Dobson circulation (opposite to what happens in most climate change experiments)
polar stratospheric cooling: poleward shift in extratropical storm stracks – “very” sensitive to forcing’s “level and depth”; stratospheric Brewer-Dobson circulation weakens in midlatitudes, strengthens at high latitudes “because of anomalously poleward heat fluxes on the flank of the polar vortex.”
polar surface warming: equatorward shift in extratropical storm tracks
responses to forcings in general: some differences between equinox and winter, nonlinear responses (sum of responses to individual forcings not equal to response to all forcings together)
…
(my speculation following abstract only: so maybe we have poleward shift, followed by equatorward shift when most arctic ice loss occurs (in ~winter +/-), followed by continuing poleward shift?)
especially recommended
***
Butler, Amy H., David W. J. Thompson, Thomas Birner, 2011: Isentropic Slopes, Downgradient Eddy Fluxes, and the Extratropical Atmospheric Circulation Response to Tropical Tropospheric Heating. J. Atmos. Sci., 68, 2292–2305.
doi: http://dx.doi.org/10.1175/JAS-D-10-05025.1
http://journals.ametsoc.org/doi/abs/10.1175/JAS-D-10-05025.1
http://www.atmos.colostate.edu/ao/ThompsonPapers/ButlerThompsonBirner_JAS_2011.pdf
(tropical tropospheric latent heating, eddy fluxes of PV, heat (which is like PV at the surface))
(see also Schneider 2006 because of isentropic slopes?)
——–
… AND THE STRATOSPHERE:
especially recommended
***
Simpson, Isla R., Michael Blackburn, Joanna D. Haigh, 2009: The Role of Eddies in Driving the Tropospheric Response to Stratospheric Heating Perturbations. J. Atmos. Sci., 66, 1347–1365.
doi: http://dx.doi.org/10.1175/2008JAS2758.1
http://journals.ametsoc.org/doi/full/10.1175/2008JAS2758.1
http://journals.ametsoc.org/doi/pdf/10.1175/2008JAS2758.1
(compares different distributions of stratospheric heating, including one that is implied (in the abstract; haven’t read it through) to correspond to solar effects)
(interesting graphs; jet and storm track shifts, index of refraction (see p. 1356, equation 4))
especially recommended
Simpson, Isla R., Michael Blackburn, Joanna D. Haigh, 2012: A Mechanism for the Effect of Tropospheric Jet Structure on the Annular Mode–Like Response to Stratospheric Forcing. J. Atmos. Sci., 69, 2152–2170.
doi: http://dx.doi.org/10.1175/JAS-D-11-0188.1
http://journals.ametsoc.org/doi/abs/10.1175/JAS-D-11-0188.1
(refraction, critical line, momentum flux, equatorial stratospheric heating, effects of eddy phase speeds)
see also
Barnes, E.A., D.L. Hartmann, D.M.W. Frierson, and J. Kidston, 2010, and
Barnes, E.A., and D.L. Hartmann, 2010
Haigh, Joanna D., Michael Blackburn, Rebecca Day, 2005: The Response of Tropospheric Circulation to Perturbations in Lower-Stratospheric Temperature. J. Climate, 18, 3672–3685.
doi: http://dx.doi.org/10.1175/JCLI3472.1
http://journals.ametsoc.org/doi/abs/10.1175/JCLI3472.1
especially recommended
***
Miller, R. L., G. A. Schmidt, and D. T. Shindell, 2006: Forced annular variations in the 20th century Intergovernmental Panel on Climate Change Fourth Assessment Report models. J. Geophys. Res., 111, D18101, doi:10.1029/2005JD006323.
http://www.image.ucar.edu/idag/Papers/Miller_annularpatterns.pdf
(troposphere-stratosphere coupling, GHG, anthropogenic aerosol, and volcanic forcing, models vs. observations)
Hartmann, D. L., J. M. Wallace, V. Limpasuvan, D. W. J. Thompson and J. R. Holton, 2000: Can Ozone Depletion and Global Warming Interact to Produce Rapid Climate Change? Proc. Nat. Acad. Sci., 97, 1412-1417.
http://www.pnas.org/content/97/4/1412.abstract
… H2O in the STRATOSPHERE:
*
Maycock, Amanda C., Manoj M. Joshi, Keith P. Shine, Adam A. Scaife, : The circulation response to idealized changes in stratospheric water vapor.
Journal of Climate 2012 ; e-View
doi: http://dx.doi.org/10.1175/JCLI-D-12-00155.1
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00155.1
(abstract:
)
————
… H2O AND STRATOSPHERE:
especially recommended
climate change
***
Scaife, Adam A., Thomas Spangehl, David R. Fereday, Ulrich Cubasch, Ulrike Langematz, Hideharu Akiyoshi, Slimane Bekki, Peter Braesicke, Neal Butchart, Martyn P. Chipperfield, Andrew Gettelman, Steven C. Hardiman, Martine Michou, Eugene Rozanov, Theodore G. Shepherd, 2012: Climate change projections and stratosphere–troposphere interaction. Climate Dynamics, 38, 2089-2097.
DOI 10.1007/s00382-011-1080-7
http://atoc.colorado.edu/~jweiss/5060/ScaifeEtAl2011.pdf
http://link.springer.com/article/10.1007%2Fs00382-011-1080-7#
(from abstract: many extratropical regions: increases in winter rain, flooding; stratospheric circulation has significant regional effects; changes consistent with stratospheric winds affecting growth rate of baroclinic eddies through depth of troposphere, “A change in mean wind structure and an equatorward shift of the tropospheric storm tracks relative to models with poor stratospheric resolution allows coupling with surface climate. Using the Atlantic storm track as an example, we show how this can double the predicted increase in extreme winter rainfall over Western and Central Europe compared to other current climate projections.“)
————-
H2O:
especially recommended
climate change
***
Booth, James F., Shuguang Wang, Lorenzo Polvani, 2012: Midlatitude storms in a moister world: lessons from idealized baroclinic life cycle experiments. Clim Dyn, ?, ?.
DOI 10.1007/s00382-012-1472-3
http://www.columbia.edu/~lmp/paps/booth+etal-CLIMDYN-2012-onlineversion.pdf
http://pubs.giss.nasa.gov/abs/bo03200f.html
(I’ve only looked at this a little tiny bit, but p. 3/16 indicates cartesian geometry and constant f; I’d be curious what corrections would be found for spherical effects)
(abstract, emphasis mine:
)
(the part about vertical vs horizontal extent doesn’t surprise me (not that any of it does))
***
Schneider, T., P.A. O’Gorman, and X. J. Levine, 2010: Water vapor and the dynamics of climate changes. Rev. Geophys., 48, RG3001,
doi:10.1029/2009RG000302.
http://www.agu.org/pubs/crossref/2010/2009RG000302.shtml
http://arxiv.org/pdf/0908.4410.pdf
(H2O vapor dynamic effects = latent heating;
majority of abstract, emphasis mine:
)
**
Dettinger, Michael
Atmospheric Rivers
http://www.scwa.ca.gov/files/docs/outreach/calendar/extreme-events/Atmosperic%20Rivers%20Dettinger%20EE%203-14-12.pdf
(slide 13/26 – AR vs PE ?)
(slide 24 refers to climate change)
————–
***
Muller, C. J., P. A. O’Gorman, 2011: An energetic perspective on the regional response of precipitation to climate change. Nature Climate Change, 1, 266-271.
doi:10.1038/nclimate1169
http://www.nature.com/nclimate/journal/v1/n5/abs/nclimate1169.html
http://www.gfdl.noaa.gov/cms-filesystem-action/user_files/cjm/mullerogorman11naturecc.pdf
(most of abstract:
)
***
Held, Isaac M., Brian J. Soden, 2006: Robust Responses of the Hydrological Cycle to Global Warming. J. Climate, 19, 5686–5699.
doi: http://dx.doi.org/10.1175/JCLI3990.1
http://journals.ametsoc.org/doi/abs/10.1175/JCLI3990.1
http://www.gfdl.noaa.gov/bibliography/related_files/ih0601.pdf
(H2O water vapor abundance shaped by Clausius-Clayperon relationship, H2O evaporation rate shaped by energy fluxes. One is larger than the other. Consequences for circulation.)
(it gets easier to summarize if you wait longer after reading it)
(PS I’d add – unless they address this – it’s been ~ 2 years since I read it, but anyway – with increasing greenhouse (LW) forcing having some effect at the surface (not generally equal to tropopause or TOA levels), the convective energy flux should tend to increase ?. H2O vapor especially adds to that effect over some range of temperatures, until saturation at a temperature higher than present (when net LW surface cooling approaches zero) – provided sufficient RH (presumably low RH just delays the effect?). H2O also absorbs some SW radiation, so beyond that point, H2O would reduce SW heating of the surface and thus reduce convective heat flux from the surface. Cloud LW feedback …? albedo feedback in general, except that associated with atmospheric solar heating, would increase convective heat flux when it is positive. The fraction of convective heat flux that is latent heat tends to increase with temperature, so that would tend to peak after the peak in total convective heat flux. Would there necessarily be a peak if it were solar forcing, or would H2O LW saturation at the surface with increasing H2O SW absorption and … scattering? (clouds aside) … just slow the increase in convective surface cooling? Convection regionally can be larger than otherwise given some regions where convection heats the surface.)
Shiu, C.-J., S. C. Liu, C. Fu, A. Dai, and Y. Sun (2012), How much do precipitation extremes change in a warming climate?, Geophys. Res. Lett., doi:10.1029/2012GL052762, in press.
http://www.agu.org/pubs/crossref/pip/2012GL052762.shtml
(abstract:
)
————-
‘PALEOCIRCULATION’
*** (Paleoclimate, high latitude amplification)
Lee, Sukyoung, Steven Feldstein, David Pollard, Tim White, 2011: Do Planetary Wave Dynamics Contribute to Equable Climates? Journal of Climate, 24, 2391-2404.
DOI: 10.1175/2011JCLI3825.1
http://www.meteo.psu.edu/~sbf1/papers/equable.pdf
JUST BECAUSE IT’S INTERESTING
Sabato, Jude S., 2008: CO2 Condensation in Baroclinic Eddies on Early Mars. J. Atmos. Sci., 65, 1378–1395.
doi: http://dx.doi.org/10.1175/2007JAS2504.1
http://journals.ametsoc.org/doi/full/10.1175/2007JAS2504.1
(cites Fantini 2004)
CLOUD FEEDBACK
Hartmann, D. L. and K. Larson (2002), An important constraint on tropical cloud – climate feedback, Geophys. Res. Lett., 29(20), 1951, doi:10.1029/2002GL015835.
http://www.agu.org/journals/abs/2002/2002GL015835.shtml
Why are so many trees falling? (Seattle weather blogger Cliff Maas)
“… my hypothesis is that we had a wet, snowy period with consistently cool, but not super cold, temperatures in a range that promoted sticky snow. No major wind events to blow off snow. No pineapple express warming. It all game together in a very unusual way, causing massive snow loading on trees. Another contributor might be the mild temperatures that have left the ground unfrozen and thus less able to hold the trees in place. …”
Mr. Perwis:
I should have pointed out that the following projection is supralinear in my terminology, since they include a t^2 term
“Another example is Rignot et al (2011), which gives yet another linear extrapolation and finds that “At the current rate of acceleration in ice sheet loss, starting at 500 Gt/yr in 2008 and increasing at 36.5 Gt/yr2, the contribution of ice sheets alone scales up to 56 cm by 2100.”
Mr Patrick 027 writes:
“Most of these (in I. and II.) I have only skimmed…”
“I will probably never read through it all, …”
Sir, you are discourteous. Many decades ago, I sometimes used to receive letters that had a postscript:
“Dictated, but not read”
Your post elicits the same response in my mind. If you feel that we should pay attention to your compendium of links, might you be gracious enough to read the articles first ?
sidd
AMEG: GeoEngineering [GE] with sulfur compounds really turns me off because they oxidize to form sulfuric acid. We have been trying really hard to get H2SO4 out of our air. Other GE: Covering the Arctic ocean with ping pong balls must be some kind of pollution.
To rephrase my question, is AMEG just another fringe group that belongs in the borehole? I am well aware that RC has pronounced methane hydrates and melting tundra to be minor issues, at least for now. Does AMEG damage the cause by being a fringe group or is there no such thing as bad publicity?
Jim Larsen #322,
“I didn’t read the proposal and would guess the principals don’t paint the ramifications as bleak as you seem to propose – that the fate of the world hangs on what we do in the next few months. Hmm, care to buy my slightly used Mayan calendar?”
Read the proposal; I basically just quoted from it.
sidd – “shut up and calculate. Hansen is not lacking in wits or resource. He can do much better than curve fitting, that’s why I find his note disappointing.”
North Carolina’s senators, however, have tried to stop state-funded researchers from releasing similar reports. The law approved by the senate on 12 June banned scientists in state agencies from using exponential extrapolation to predict sea-level rise, requiring instead that they stick to linear projections based on historical data. http://www.scientificamerican.com/article.cfm?id=north-carolina-sea-level-rises-desipte-senators
Apparently Hansen is not alone with this “fitting” or what you call it. And then there are abrupt developments to expect, which suggest extreme developments to come. Then consider his track record on projections. Even with all the really conservative IPCC estimates on 2100 SLR, he was on this and each year the “general consensus” is further coming in line with what Hansen had calculated much earlier.
Kinematic First-Order Calving Law implies Potential for Abrupt Ice-Shelf Retreat http://climatestate.com/pure-climate-science/item/kinematic-first-order-calving-law-implies-potential-for-abrupt-ice-shelf-retreat.html?category_id=79
And then there is this:
The researchers estimate that 50 per cent of the West Antarctic Ice Sheet (1 million km2) and 25 per cent of the East Antarctic Ice Sheet (2.5 million km2) overlies preglacial sedimentary basins, containing about 21,000 billion tonnes of organic carbon. Team leader, Professor Wadham said: “This is an immense amount of organic carbon, more than ten times the size of carbon stocks in northern permafrost regions. http://climatestate.com/pure-climate-science/item/potential-methane-reservoirs-beneath-antarctica.html
Edward Greisch #337,
” is AMEG just another fringe group that belongs in the borehole?”
According to the Collins Dictionary, a ‘fringe group’ is defined as ” a group that is on the periphery of a larger organization because its views are more extreme than the majority”. Not necessarily a negative connotation. If the mainstream is going in the wrong direction, it may be a positive connotation.
Two academics listed in AMEG are Stephen Salter and Peter Wadhams. Salter has a background in wave energy conversion and cloud albedo enhancement, and Wadhams has been making ice measurements in the Arctic for decades. Both appear to be highly credible. They see the collapse of the Arctic as we speak, with the potential for unknown damage. The Strategic Plan comes across to me as an act of desperation by well-meaning people who are seeing no action being taken to contain the damage. The proposal is obviously flawed, as a few posters have already pointed out. Tell me, what other choices do they have to get something done?
“I am well aware that RC has pronounced methane hydrates and melting tundra to be minor issues”
On Arctic ice and related issues, I would give higher priority to Wadhams’ views.
[Response: We have asked for, and not received, any backing for Wadham's views for an exponential fit to the ice volume. This is the sole 'evidence' for his prediction of an ice free summer in 2015, but that is not in any way convincing to most everyone else, and so, yes, this prediction (and the dramatic consequences that are supposed to follow) is 'fringe'. Sometimes fringes are right, but in science they dominate by the weight of evidence, not authority. - gavin]
Operation Icebridge, Dec. 2012 — here’s the developing large crack in the ice stream mentioned above:
http://www.youtube.com/watch?v=anfbjiShjP8
Re 336 sidd – I understand the sentiment, but I read the abstracts I provided, and didn’t ask anyone to read any farther – actually didn’t ask anything at all. I hope to read more; if someone else does too, great, if not, well I certainly understand why. It’s there for those who want it. That was the intent. Sorry for the misunderstanding.
… oh, I guess you took the word ‘recommendation’ as unconditional and complete, as in ‘you must read this whole thing regardless of your interest’. Well I didn’t mean it that way. Okay, done.
323 Superman1 asked, “why would one select a symptom, rather than the problem and its causes?”
Ahh, Engineering attempts to engage in Public Relations….
Cuz the goal is to have the public give a damn. The public is on a 1 hour news cycle, so unless it’s happening RIGHT NOW, it’s, like, whatever.
Biggest melt ever. Hollywood-style exaggeration but it’s real life reported (or not) in real time.
Not that it lit the public’s fuse, but I think the topic was spot on perfect for an initial post made at that time.
The lesson here is clear. If you want to make a political difference, forget PACs. Invest in mass media and leverage your voice.
Seriously, the analogy for Climate Change is exercise. Ya know you oughta do it. Ya know you’ll be better off. You’ll feel better, more energy, yada yada yada….
But skipping today won’t hurt, and exercising today will do so little as to be no good (0.2 pounds?? woo.) and won’t be near as much fun as that bag of chips…
323 Superman1 said, “I suspect my views on what you call an ‘interesting discussion’ differ from yours.”
Probably. You head straight for the prey. I see around corners.
S1 asked, ” what fraction is attributable to anthropogenic forcing; what can we expect if present trends continue. Why did the flagship discussion not address this central problem?”
In the battle for a scrap of desert amongst the descendants of two brothers who worship the same god in slightly different ways (Palestinians and Jews), the actual sitting at a table in the same room – the arrangements, the tiniest detail which might suggest superiority of morals or power had to be addressed. That sort of thing takes decades….
It was/is a friggin kindergarten stupid family squabble.
Skeptics VS Warmists. Yep, we’re right. So? We still have to get to the table.
So a symptom we all can see. Something which God has Revealed (to continue the religious analogy). By finding agreement in something, it sets the tone for finding agreement in larger issues, and it eliminates wiggle room. Things we disagree on are often best left for later. Find another thing we can agree on. Eventually, the mosaic we create with such agreements will lock in the truth for things we could never directly resolve.
S1 said, “Once in a century storms are occurring once on a decade or sooner. That should have been the focus of the flagship issue, but instead, a symptom, with its higher variability, was chosen for the focus.”
They’re both symptoms. The drought is more local, which helps PR, but the sea ice is less controversial, which helps agreement. The model for success isn’t Our Side beating The Evil Opposition to death, but building a new consensus with the mindset that EVERYONE at the table is TRULY INTERESTED in finding the REAL truth. (The caveat is that many feel the best place to find the REAL truth is in THEIR beliefs. That’s not immoral. We cherish folks who do works through faith.)
S1 went into a funding rant….
dude. Chill.
The “Alarmist” argument (which I often agree with) wasn’t missing by intent. At least two Alarmists were asked to participate. One never responded. The other accepted, and then backed out due to lack of time.
324 perwis quoted, ” “As the terminus of an ice stream retreats inland, glacier sidewalls can collapse, creating a wider pathway for disgorging ice.”
yeah, but adding 5 miles of fjord just makes it HARDER for ice to get from the receded glacier to the ocean. Woo if it’s wide. I know that the ice/water interface can enlarge, but disgorgement has got to be hindered by retreat. (Here’s where I hope somebody fills in what I’m missing)
327 Lawrence C, I agree completely. I’m no expert and can’t quantify, but as the ocean waters increase in temp, one would have to target colder and colder surface air temperatures to achieve whatever September ice extent is desired. I’m sure that the “instantness” would slow down too. With a warm Arctic Ocean and warm waters flowing in from a warm world, it could take years of induced brutal winters to cool the system back to a semblance of normal.
338 S1 said, “Read the proposal; I basically just quoted from it.”
No thanks. I mostly just wanted to know if your stance reflected theirs. If so, your excerpts were plenty.
342 Patrick,
Perhaps a better leading synopsis? I got the impression of a ton of stuff tossed in my direction with nary a clue as to why or what. That there was “1000 pages” sitting in front of me might have contributed to my failure. Whether I was typical or not, I briefly pseudo-scanned and got nada.
MODERATORS:
I am getting “could not open socket” on perhaps 2/3rds of my submissions. It fixes itself without changes. I’m on OS X 10.4.11
Re Jim Larsen @ 346 – had the same problem last night.
@ 345 – thanks for the feedback. I think I tend to expect that stuff will take up fewer lines than it actually does. Perhaps I was too focussed on getting it posted before one more day passed. I’ve been working on this since I think early November, and actually even earlier than that. Part I was supposed to be about climate change specifically so some of my tags were gratuitous; also, except for the Wing paper, the ‘especially recommended’ should have been dropped; I started out knowing that I wanted to tag some sources with that label but over time I perhaps over or under-used it; it would have been better just to put the citations in bold as an attention-grabber.
I don’t want to stop anyone from digging in, but I wanted to eventually post a brief intro into some subject matters that would make these articles more understandable. The problem is, there’s a few i’s to dot and t’s to cross on my side before I’m ready to do that, and I just didn’t want to sit on all these articles until I had time to read through them more. At least I’ve got the abstracts under my belt now.
Also, when I do try to write an ‘intro to planetary fluid dynamics’, I’m going to want to provide citations, and that’s the boring, tedious part (for me), so I figured it might go faster (for me) to post a list of articles first; I could always refer back to those postings at a later time. Having the list put together should help me avoid reading a bunch of stuff and then typing about it having forgotten what came from where.
As for those articles which I don’t anticipate reading beyond the abstract, I think they still serve a purpose in:
1 Some are cited by the articles that I will go through, and it’s nice to have the citations and links there already in case I need them.
2 While one must be careful about taking things out of context, I thought I might use some things as reference material where I’d read the parts that provide what I’m interested in. Case-in-point: Vasavada, Ashwin R., Adam P. Showman, 2005: Jovian atmospheric dynamics: an update after Galileo and Cassini. Rep. Prog. Phys., 68, 1935-1996.
doi:10.1088/0034-4885/68/8/R06
http://www.lpl.arizona.edu/~showman/publications/vasavada-showman-2005.pdf
- I don’t anticipate getting through the whole thing any time soon (because gas giants aren’t the focus), but there were about ten pages in there which provides a nice summary of how eddies can form and drive jets (quasi-/__-geostrophic turbulence, Rhines scale, forcing and dissipation) and a really neat diagram with a page (1967) that gave me a much better understanding of how/why Taylor columns would fit in Earth’s outer core (than I got from Karato – nothing against Karato; great (geology) book) – which I realize is going off on a tangent but why explain PV and then strictly limit yourself to thin-shell stably-stratified fluids?
- also, there are some websites that provide information which I already know a lot, so I’d just be reading parts of them.
3 It provides an awareness of the issues to see that their are articles about particular things. I think this can motivate interest in learning about those things from the other sources (those sources which are better for introductory purposes or have a bigger-picture outlook).
And of course once I had a list put together I wanted to post it.
PS I wasn’t going to post quoted abstracts for everything in part II; I just figured it made sense to do that for part I (I see I forgot one).
Jim Larsen #345,
“n the battle for a scrap of desert amongst the descendants of two brothers who worship the same god in slightly different ways (Palestinians and Jews), the actual sitting at a table in the same room – the arrangements, the tiniest detail which might suggest superiority of morals or power had to be addressed. That sort of thing takes decades….”
This is ‘superficiality’ carried to new heights! The above diversions are meant for public consumption only. The central problem is that each side would like to gain control of the full territory. The Israelis would like to cover the West Bank and Gaza Strip with new settlements, and have the Palestinians emigrate to other Arab states. The Palestinians would like to send the Israelis back to Europe (the main group), and turn the whole region into a Palestinian State. Until those fundamental issues change, the superficialities will dominate the news.
We had the same problem in Korea and Vietnam. The Paris Peace talks in Vietnam, and similar talks in Korea, were delayed, according to the Press, by differences on the shape of the table and who sat where. The central problem was neither side was ready to surrender or negotiate, so they engaged in these superficialities.
In climate change, we have a similar problem, but with an added dimension. Rather than recognize the inherent addictive nature of the problem, we focus, as you did repeatedly, on the need for public information and political action. If the problem were lack of information, then the solution would be dissemination of information. But, if the problem is addiction to intensive use of cheap fossil fuel energy, then the solution is not merely provision of information, but addressing the addiction head-on. But, it’s so much more convenient to blame the cartels than the addicts.
MODERATOR: I also get the same socket errors and could not post at all yesterday.
sidd @330
I am not saying that Hansen & Sato sufficiently justifies the hypothesis that mass loss will follow an exponential curve. However, the arguments they provide give reason for concern that mass loss will be accelerating, at some faster-than-linear pace. Of course, exponential developments are a very special case, and it would be interesting to read more justification from Hansen regarding the hypothesis of exponential mass-loss of the great ice-sheets.
It is correct that Rignot et al:s projection is supra-linear (it is accelerating ice-loss), but they assume a linear acceleration. It is not far-fetched to assume that ice-loss will be accelerating more in the end of the century under BAU-forcings. Will it be exponential? Maybe not, but can we rule it out?
Hansen & Sato also points out that recent sea level projections are primarily based on linear assumptions. Notably, this include the “back-of-the-envelope” calculations for ice dynamics in IPCC AR4, expert judgments such as Pfeffer et al (2008) or Katsman et al (2011) (see my discussion in post # 324), as well as the the semi-empirical methods by Vermeer & Rahmstorf (2009) and others (Rahmstorf, Perrette & Vermeer (2011) say that “a non-linear response of ice sheets could make semi-empirical projections overestimate or underestimate the true future sea level rise.”). I would argue that the linear assumtions are not justified based on the exatcly the kind of phenomena that Hansen & Sato (2012) highlights.
The billion-dollar question is if the current ice-sheet models are any better. My understanding is that the forthcoming AR5 sea level projections rely on ice-sheet models for estimating the future contribution from ice-dynamics (which is where the main uncertainty is, see my post #303 above).
I read Hansen & Sato’s recent note and their brief discussion of this in Hansen & Sato (2012) as yet another warning of scientific reticience regarding sea level rise and that current methods for sea level projections probably does not sufficiently capture the scale and speed of the loss that can occur over short periods of time (this century) due to non-linear responses of the great ice-sheets in Greenland and Antarctica.
Jim Larsen #345,
“The “Alarmist” argument (which I often agree with) wasn’t missing by intent. At least two Alarmists were asked to participate. One never responded. The other accepted, and then backed out due to lack of time.”
Okay, so if you’re scheduled for major surgery, and the first two anesthesiologists the surgeon requests back out, you’d go ahead with the surgery anyway? What was the rush for the dialogue without a balanced team?
On to a more fundamental issue. I have been promoting the viewpoint that the major roadblock to combating climate change is the effective ‘addiction’ of the energy consumer to cheap and plentiful fossil fuel-supplied energy. That seems not to be resonating on this site. Instead, the focus appears to be ‘let’s target the media for not getting the correct info to the public, and the energy companies for their media and political influence’. Now, if I believed info restriction or undue political influence were the major roadblocks, then I would agree that the focus on the media or the politicians is appropriate. But, if the consumer is the major roadblock, and the consumer drives the politicians, then the focus on the politicians has it backwards, and can never solve the problem. Any politically-driven mandates on heavy energy use restriction, or politically-driven taxes/penalties on heavy fossil fuel use will go nowhere without public acceptance. So, it seems to me from first principles that the energy consumer is the central problem, and solutions can only come when the energy consumer is willing to forego his ‘addiction’. This could either be voluntary or involuntary.
Now, if this message is not being received, it seems to me there are three potential major causes: there is a problem with the transmitter, there is a problem with the transmitting medium, there is a problem with the receiver, or any combination of the above. So, where are the main problems? Do you disagree with the fundamental message presented above? If so, tell me how the politicians could institute the required harsh changes without the consent of the energy consumer? Any other comments would be appreciated as well.