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Unforced variations: Dec 2012

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A new meteorological season, perhaps some new science topics to discuss…

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369 Responses to "Unforced variations: Dec 2012"

  1. Patrick,

    Your project might be better served by a blog site. As it evolves you could post executive summaries here along with a link to your site. That’s appropriate because this is a comments section, not a Guest Post.

    And linking back to old Unforced Variations posts, which can’t be corrected or updated, well, it won’t work. You’ll surely have a deeper knowledge and better words later. Once all the pieces of a system are in place, tons of stuff simplifies and the chaff can be raked out – unless you’re using a write once site like RC – especially when things are spread out amongst many Unforced Variations. When one’s highest sort key is MonthPosted, well, obsolete stuff which can’t be updated will be hard to keep track of….

  2. 348 S1 said, “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?”

    Instead of making everyone do the Groundhog Day thing, how about you read the whole CD discussion? You’ll find that plenty of folks, including me, had that same concern.

    S1 said, “solutions can only come when the energy consumer is willing to forego his ‘addiction’. This could either be voluntary or involuntary.”

    Complete drivel, there. One sentence contradicts the previous. Willing to involuntarily forgo his addiction? PWI? (or in some states PUI)

    There’s a structure called the amygdala in the brain which screams when it recognizes danger. It’s got veto power over logic. I’m guessing your posts are generally amygdala-driven.

  3. 348 S1 said, “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?”

    I just noticed how your analogy fits your beliefs. Filling out the story:

    “Without the surgery you’ll be dead in a week. Each day you delay the surgery will halve your odds of survival.”

    So… do you endure the pain? After all, the safest anesthesia is none at all, which fits perfectly with your desired solution.

  4. S1, it seems you’re discovering issues , or are figuring this all out all by yourself, for the first time.

    People have been working on these for quite a while, actively, worldwide. Look at some of the sidebar blogs — you’ll find the discussions well under way.

    RC has been pointing to those discussions for a long time now.
    Pointing, because they’re happening _there_. Not here where the science is being learned by those interested in it as it happens.

    Read, for example, the links at EcoEquity (to pick a personal favorite off that long list in the sidebar).

    You’re not alone. You’re catching up with work well advanced.
    Figure out which ways people are going, and decide who to join.

    Remember: delay is the deadliest form of denial. Delay for example as done by the tobacco and chemical industry over decades by funding opposing sides of a policy issue — to pull people apart, generate extremes at the cost of the center, and leave a vacuum where people might agree on policies. Be wary.

  5. re 351 Jim Larsen – thanks, I’ll consider it –
    – problem: I have very little knowledge of starting a blog (I suppose there’s a ‘blogging for dummies’ book out there…)
    – but it is possible to link back to a single comment, so that’s not an issue – I don’t think.

  6. Here, for example — follow the pointer to EcoEquity:

    America’s first “climate dividend”
    Where they point to, and recommend, what they describe as a
    —- excerpt follows —-

    Great piece in the Huffington Post today on California’s new climate regime. Mike Sandler, in a piece called The Birth of Carbon Pricing and Delivering California’s First ‘Climate Dividend’ can see what, alas, many climate activists miss — allowance auctions can be understood in a very positive light indeed. Sandler writes here of America’s first climate dividend and offers an analysis that is astute in both its details (which I will skip, hoping that you read the article) and its overall import.

    He even quotes the mad utopians at the California Public Utility Commission on the commons logic that is carefully embedded in the new system ….”
    —— end excerpt —-

    More under “Other Opinions” in the sidebar.

  7. Mr. Perwis:

    A review by Joughin et al. (Science,2012,v338,pp1172 et seq.) of oceanic influence on ice sheets might interest. Oceanic heat transport drives basal melting of ice shelves but the process is not well understood. The modelling difficulty is that the resolution of current GCMs are too coarse. When finer scale models are applied the results are more dire.

    “Where regional-scale ocean models have been coupled to GCMs, the results indicate the potential for far more extreme changes within this century than had been anticipated (26).”

    The Hellmer paper, ref 26,(Nature,2012,v485,pp225 et seq.) is an unsettling analysis of the Filchner-Ronne shelf, usually considered stable. A quote

    “… our melt rates have to be considered as lower bounds.”

    These ‘lower bounds’ show strong basal melt commencing in the second half of this century. One model at fine resolution (FESOM, exhibited in the supplementary material) shows basal melt beginning in the 2020s.

    The last two sentences in Joughin are:

    “The remaining challenges require a coordinated and sustained effort by glaciologists, oceanographers, and climate modelers before reliable projections of future sea level can be made. Until that time, Greenland and Antarctica will remain the “wild cards” in sea-level projections.”

    I think you will agree that papers such as these are much better than curve fits to mass waste measurements.

    sidd

  8. Patrick, wordpress blogs are free and user friendly, the widgets are self explanatory, setting up takes less than an hour, google takes about six weeks to include so action will be slow at first

  10. Mr. Larsen:
    The section on tidewater glaciers in the Joughin paper I referred to in my previous comment might help you with your question:
    “…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)”

    Very briefly, from the paper: ” It is important to note that many fjords are choked with a mélange of sea ice and icebergs (Fig. 4) that can extend deep (>100 m) into the water column.”

    Here Figure 4 is a revealing picture of JI

    “Another way that warmer fjord waters may contribute to glacier retreat and speed-up is through the influence of melt on the ice mélange choking many glacier fjords (Fig. 4), especially in winter. In summer, the mélange’s constituent icebergs typically float freely, but in winter sea ice bonds them together to form a rigid mass that is pushed down the fjord by the advancing glacier terminus (42). Although the strength of this amalgam should have only a small effect on the back stress, observation and theory both indicate that it can suppress wintertime calving (42, 43), which picks up again in spring and summer when the mélange remobilizes and clears the fjord. On Jakobshavn Isbræ, this seasonal variation of calving rates allows the terminus to advance over the winter and retreat during the summer, causing its speed to vary annually by 20 to 30% near the terminus. Warmer water in the fjord may shorten the period when the mélange is frozen, causing retreat by lengthening the duration of when strong calving occurs. ”

    Mr. Perwis:
    Another supralinear factor for GRIS is the albedo flip, detailed in Box’s meltfactor blog and in Tedesco.

    One big supralinear factor for WAIS, is the retrograde slope of the bed beneath the ice, as Joughin points out

    “The bedrock geometry on which an ice sheet rests provides an important control on its stability. With no ice-shelf buttressing, ice discharge scales nonlinearly (n > 3) with grounding-line thickness, making it difficult to stabilize the grounding line on slopes where the bed deepens with distance inland (7).”

    n>3 is huge, as Weertmann and Mercer knew, and Schoof explicitly calculates in Ref 7.

    sidd

  11. Patrick said, “but it is possible to link back to a single comment, so that’s not an issue – I don’t think.”

    But comments are often followed by clarifications, corrections, and extensions. To which correction do you point? Previously solved errors will reappear, and you’ll end up with spaghetti code.

    I’m in the same boat with regard to creating a blog. I chose Blogger. It’s free and so far not bad. My first substantial post, To EV or not to EV, is getting close to first publication.

  12. Weertman, Lliboutry and the development of sliding theory
    A.C. FOWLER
    http://people.maths.ox.ac.uk/fowler/papers/2011.4.pdf
    is a review of the controversial development of glacial sliding theory. I but quote one sentence; “Weertman’s simple theory is still often used, but it should
    not be.”

    The paper is not difficult to skim and the essence of the problem ought to emerge. I commend this review to anyone interested in the movement of glaciers and ice streams.

  14. sidd, Jim Larsen @359:

    Jason Box’s blog post on the Ilulissat glacier (also known as the Jakobshavn Isbrae) illustrates my worries:
    “Flying over Ilulissat glacier this July, it was stunning to notice how retreat has proceeded upstream into a northern tributary, producing effectively two main calving fronts to this ice sheet outlet. The faster stream from the west off the right side of the photo also remains in retreat. The glacier is based below sea level more than 75 km inland (Thomas et al. 2011).” http://www.meltfactor.org/blog/?p=762

    Adding miles of fjord only have a limited effect by making it harder for the ice to travel to the ocean (see the quote by Joughin et a above). Instead, retreat of the glacier grounding lines far into the ice sheet seems bound to create wider outlets, effectively activating new ice streams in the ice sheet, which seems to have happened recently in the Iluissat glacier.

    Glaciologist Robert Bindschadler puts it very succinctly: “there is no physical reason … that those outlet glaciers won’t just eat out the heart of the Greenland ice sheet” and and regarding the outlet glaciers in Antarctica, “there is no reason they should’t be draining the entire marine-based part of the West Antarctic Ice Sheets, and perhaps similar to the East Antarctic Ice Sheet” I have linked to Dr. Bindschadler’s lecture on my blog (the quotes are at ca 51 minutes in the lecture):
    http://climatevideos.wordpress.com/2012/01/10/documentary-of-research-on-the-pine-island-glacier-and-lecture-by-dr-robert-bindschadler/ (See also the slides Dr Bindschadler uses to illustrate how large parts of the Greenland and Antarctic ice sheets are below sea level.)

    Can present ice sheet models simulate the recent behaviour of the Ilulissat glacier? Has the state of ice sheet models really advanced so far from 2007, when the IPCC found it impossible to even provide an upper bound of the potential contribution from ice sheet dynamics?

    Interesting and important as that may be, it is now new years eve and I wish contributors and commentators at Real Climate a happy new year, and best wishes for a great 2013! Thank you for all your efforts!

  17. Re 360 Jim Larsen – thanks. I guess I’ll have to really proofread before posting comments. How friendly is Blogger to equations? (e.g. is it any easier than entering html code for superscripts and subscripts and bold for vectors etc. here?)