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Thread: What about climate models?

  1. #1 What about climate models? 
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    Do you know anything about climate models? Do you have an opinion about how useful modelling is or might be?

    If you only tune in to public arguments about climate change or read about the latest study that uses climate models, it’s easy to lose sight of the truly extraordinary achievement those models represent. As Andrew Weaver told Ars,

    What is so remarkable about these climate models is that it really shows how much we know about the physics and chemistry of the atmosphere, because they’re ultimately driven by one thing—that is, the Sun. So you start with these equations, and you start these equations with a world that has no moisture in the atmosphere that just has seeds on land but has no trees anywhere, that has an ocean that has a constant temperature and a constant amount of salt in it, and it has no sea ice, and all you do is turn it on.

    [Flick on] the Sun, and you see this model predict a system that looks so much like the real world. It predicts storm tracks where they should be, it predicts ocean circulation where it should be, it grows trees where it should, it grows a carbon cycle—it really is remarkable
    .”


    That's a quote from this (quite long) article about climate modelling. (My emphasis, my paragraphing.)

    Why trust climate models? It’s a matter of simple science | Ars Technica

    The article also points out problems with observations that aren't immediately obvious. Once it's pointed out that satellites taking images from above simply cannot see lower level clouds when there are higher level clouds in the way, it's instantly an issue if you're one of the poor souls trying to research low level cloud behaviour. There are no observations to check your conclusions against, you have to find some other indicators to work things out. Which probably means bonus! more hours, more reading, more research for you to slog through to work out the best way to test things.

    Strongly recommend the whole three pages if you're at all interested in climate generally and modelling in particular.


    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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    The clash here is between two questions. The first asked by science: "What's the best we can predict?" The second asked by politics. "What's the best for our interests that we can get people to believe?" It shows a deeper conflict between two paradigms - one where truth is absolute and waiting to be discovered, (science) and a another where truth is created by consensus. (politics)

    Minimizing this nonsense conflict is a big challenge of our time. We're in the situation we're in because it makes sense to do what we're doing: The cheapest joules come from status quo methods, like fossil fuels. But there are truly side effects of these methods that are undesirable, like climate change. A simple scientific study of politics will reveal that no one can change us from the status quo, because to do so would dramatically decrease energy availability, and thus crash the economy, getting said leader booted from office. Therefore solutions to problems we face are scientific in nature, and can't depend on consensus (to inflict short term hardship on ourselves) in a democratic political system.

    But solutions are out there. Consider this:
    Algae To Oil In 1 Hour | CleanTechnica
    Also, consider the tech I recently found which give you coal combustion (I can't find link) with the C02 output stream completely separated. Now the algae feeds on C02. The algae needs to be pressurized and heated to 300 C to turn into fossil fuels. Coal power often heats water to these hight heats/pressures to turn turbines, but substitute the algae liquid mix. The result of this napkin sketch is basically solar subsidized coal: (ideally) Twice the joules, the same amount of carbon as a normal coal plant. We can do this. In fact, we can do a lot of things, and we can do them in a way like with the above, where economy=ecology, and we actually utilize the waste products like C02 to make more energy. It just takes time, work, and effort. But in the end it translates into $$$ for the investors, and a cleaner world. All this from good science.


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    Really? Did you read the link? It's strictly about climate science. Nothing at all about policy or technology.
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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    Quote Originally Posted by adelady View Post
    Really? Did you read the link? It's strictly about climate science. Nothing at all about policy or technology.

    Really? A link that talks about modelling with technology is not about technology?

    And news flash: Climate science is very, very, very tied to policy. That's why this article was published is because there is a huge group of people denying the validity of climate models.
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    So you think the appropriate response is to talk about technology/ policy/ politics rather than the science involved.

    When we refer to epidemiology or physics or chemistry or biology or any/most other science that relies on modelling by computers, we talk about the science and/ or how the models work - we don't talk about microscopes or syringes or other possibly related technology instead of talking about science. Generally we talk about the science and then someone who works in the area talks about some nifty technology or technique they've come across.

    Without even the briefest, passing remark about the relevance or interest or details of a comprehensive description of how modelling works, you want us to think that we should jump straight into a comparison of the various merits and drawbacks of particular technologies other than computers. I happen to know quite a lot about CHP systems around the world as well as the implementation of micro solar panels on huts in isolated villages and centralised solar systems and distributed solar in ordinary suburban environments and the recent advances in onshore and offshore wind systems and tidal systems and run of river systems as well as conventional hydro. I would have put them into the OP if that was the discussion topic.

    (I'd be careful about advancing stuff like that experimental algae-to-oil thing when Harold's around if I were you. He won't even accept that there are some places in the world where renewables are now cheaper to use for electricity production than fossils. Replacing fossils in liquid fuels is only an expensive experiment for the time being and very unlikely ever to be cheap enough for ordinary consumers, though personally I think we'll have to find something like this for specialist applications. )

    would dramatically decrease energy availability, and thus crash the economy,
    I don't see why. Old coal powered plants are already being closed down all over the place and proposed new ones are being deferred or cancelled entirely. If you're talking about the USA, all you need is to look at Europe - they have much the same standard of living and about half the CO2 emissions. You can't quickly redesign cities or build public transport systems, but you can easily reduce fuel emissions on trucks and cars to the same levels as European standards. Given the general unemployment problem, you'd also do well to retrofit a whole lot of existing housing to higher standards - double glazing, sealing draughts, better lighting. The cheapest kWhs to "replace" are the ones you no longer need at all.

    As it is, all new power generation, not most of it, all of it, that came online in the USA during November was from renewables.

    Renewable sources now account for 15.9 percent of total installed U.S. operating generating capacity: water - 8.42 percent, wind - 5.20 percent, biomass - 1.34 percent, solar - 0.61 percent, and geothermal steam — 0.33 percent. This is more than nuclear (9.20 percent) and oil (4.05 percent) combined. Note that generating capacity is not the same as actual generation. Actual net electrical generation from renewable energy sources in the United States now totals 13-14 percent.

    Renewable Energy Provides 100% of All New US Electrical Generating Capacity in November 2013
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
    "nature is like a game of Jenga; you never know which brick you pull out will cause the whole stack to collapse" Lucy Cooke
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    Quote Originally Posted by adelady View Post

    Without even the briefest, passing remark about the relevance or interest or details of a comprehensive description of how modelling works, you want us to think that we should jump straight into a comparison of the various merits and drawbacks of particular technologies other than computers.
    I don't want us to think we should do anything, that's just what I did. But you seem up for talking about it anyway, which is cool with me:

    Quote Originally Posted by adelady View Post
    I happen to know quite a lot about CHP systems around the world as well as the implementation of micro solar panels on huts in isolated villages and centralised solar systems and distributed solar in ordinary suburban environments and the recent advances in onshore and offshore wind systems and tidal systems and run of river systems as well as conventional hydro. I would have put them into the OP if that was the discussion topic.
    Again, to me that IS the discussion topic, because this is such a hot issue. On most sites you'd have responses from like five climate change deniers already, who are politically motivated, denying models work because they predict climate change. So forgive me for pre-emptively jumping in to this space, and not looking closer at the models, but...

    Quote Originally Posted by adelady View Post
    (I'd be careful about advancing stuff like that experimental algae-to-oil thing when Harold's around if I were you. He won't even accept that there are some places in the world where renewables are now cheaper to use for electricity production than fossils. Replacing fossils in liquid fuels is only an expensive experiment for the time being and very unlikely ever to be cheap enough for ordinary consumers, though personally I think we'll have to find something like this for specialist applications. )

    would dramatically decrease energy availability, and thus crash the economy,
    I don't see why. Old coal powered plants are already being closed down all over the place and proposed new ones are being deferred or cancelled entirely. If you're talking about the USA, all you need is to look at Europe - they have much the same standard of living and about half the CO2 emissions. You can't quickly redesign cities or build public transport systems, but you can easily reduce fuel emissions on trucks and cars to the same levels as European standards. Given the general unemployment problem, you'd also do well to retrofit a whole lot of existing housing to higher standards - double glazing, sealing draughts, better lighting. The cheapest kWhs to "replace" are the ones you no longer need at all.

    As it is, all new power generation, not most of it, all of it, that came online in the USA during November was from renewables.

    Renewable sources now account for 15.9 percent of total installed U.S. operating generating capacity: water - 8.42 percent, wind - 5.20 percent, biomass - 1.34 percent, solar - 0.61 percent, and geothermal steam — 0.33 percent. This is more than nuclear (9.20 percent) and oil (4.05 percent) combined. Note that generating capacity is not the same as actual generation. Actual net electrical generation from renewable energy sources in the United States now totals 13-14 percent.

    Renewable Energy Provides 100% of All New US Electrical Generating Capacity in November 2013
    I'm glad you decided all this stuff is fair game in this thread after all, I think it is interesting and important. (as are the models that predict climate change)

    I've come to the conclusion that we can't transition from fossil fuels based off what I've calculated as a strait up cost per joule, and this is pretty well reflected in our current energy usage, which is over 90% nuclear and fossil fuels, and about 85% fossil fuels. I feel strongly about this issue, because I am really concerned about climate change, but I feel the issue has become so entangled with politics that the science has fallen by the wayside: Basically, there's a camp on the right who says climate change isn't happening or downplays it, and a camp on the left who says it is happening but then advocates a purist approach, a transition to clean energy sources which isn't really economically feasible. Massively ramping up nuclear energy is the only economically viable way I can see to replace fossil fuels, and that has issues of its own, in terms of nuke making materials and waste, and initial investment cost. Systems like I mention above that temporarily sequester C02 to feed algae to produce bio-fuels seem like a way forward to me, its about bring the existing fossil fuel infrastructure into collaboration with renewable production to get substantial reductions in carbon outputs, without relying on total changes we can't afford to make.

    Those are my assessments, anyway, I'd LOVE to find out I'm wrong, and we could actually power a thriving economy and high standard of living off solar panels or something with no carbon at all.
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  8. #7  
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    a transition to clean energy sources which isn't really economically feasible
    How do you know that?

    I live in a state which now averages nearly 30% power from wind and we occasionally get days where 100% of our power is from wind. And we got to this position from a standing start a mere 10 years ago. It's been vastly helped by almost a quarter of houses having solar panels on the roof - some people don't like them for power generation reasons, but they are far and away the best demand reduction and grid management mechanism for hot days.

    There are several regions in Europe and in the USA which are doing similar things in similar time frames. And the sky hasn't fallen.
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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  9. #8  
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    Quote Originally Posted by adelady View Post
    a transition to clean energy sources which isn't really economically feasible
    How do you know that?

    I live in a state which now averages nearly 30% power from wind and we occasionally get days where 100% of our power is from wind. And we got to this position from a standing start a mere 10 years ago. It's been vastly helped by almost a quarter of houses having solar panels on the roof - some people don't like them for power generation reasons, but they are far and away the best demand reduction and grid management mechanism for hot days.

    There are several regions in Europe and in the USA which are doing similar things in similar time frames. And the sky hasn't fallen.
    Frankly? Its the recent Exxon-Mobile commercials. I know they're in the ball park of correct. The one in mind says "quiz, how many days can your smart phone run off a gallon of gas, 30, 300, or 3000?" And the answer is 3000. That's like 8 years. The raw energy fossil fuels are offering at the cost they come at simply have no competition yet. that means that policy becomes an increasingly important tool in any alternatives, and that means an increasingly empowered black energy market, which is dangerous to the well being of the state.

    The solutions are out there. There's a second commercial I've seen from them, which says "energy is life". That's correct as well. The scientific view of life on earth reveals, if nothing else, the miracle of that. Billions of years ago replicators came together with the amazing property that they consumed C02, split it up with the power of the sun (photosynthesis), formed sugars and (ultimately) hydrocarbons, and released oxygen, leading to the Oxygen Catastrophe:
    Great Oxygenation Event - Wikipedia, the free encyclopedia
    These were naturally grown solar-panels/chemical batteries, called plants. But they produced so much energy and oxygen that it created a catastrophe resulting in the existence of creatures, which, like fire, consume free oxygen and sugars and output C02 to balance things out. These fires-made-flesh were called animals, what we are.

    Thus energy is life, for us anyway. Leave the plants alone and they'll rebuild the whole thing from solar power in another few million years.

    The irony of modern times is that we seemingly would sacrifice the well being of future generations for very, short term profit... Selling ancestral gold for a few cents an ounce if it buys us another beer. The only reason this is happening is a failure of our financial system to accurately reflect the state of affairs, and to call us to a higher spiritual state, which it once did. Joules, the unit of energy, I believe are the supreme currency, which drives civilization, which drives life. The most precious thing in the this and future civilizations. And as far as spirituality? The supreme goal is to become something greater than this doomed ape body we each inhabit, with its fleeting search for meaningless pleasures, and invest in things greater than ourselves, in future generations, in others. To make the effects of one's life echo through eternity, to undermine the idea of a life lived only for the benefit of one doomed individual so many seem to embrace. To embrace not the cheap promises of spiritual "heaven" offered by the charlatans who will offer it to anyone who has a few dollars to give for "forgiveness", but rather to embrace a sort of real eternal life in tune with science: a life lived where the effects of it positively effect generations ever after, as great scientists have achieved, and generous souls as well.

    The point, as far as climate change, is that we CAN do this. We can do this, and all be better for it. It is the natural order that we will do this, and any one who stands against it will be ultimately weakened for their stance. But it takes a great love, and a great commitment to science, where we deny no reality, from the value of a gallon of gas, to the reality of climate change.

    Peace, and sorry for a kinda emotional rant.
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  10. #9  
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    Climate modeling is a darned entertaining attempt to build a map of the earth and atmosphere, then extrapolate expected changes into the future.
    When many(most? all?) are tested by looking into the past, they fail the test. Does this mean that they are rubbish?
    If one looks at early maps of exploration, it becomes obvious that most were flawed. Take those flawed maps, and predict where roads, and towns would build up, then invest in realestate for the long haul? Half of the early "white" settlements along the mississippi river are now gone, washed away by the floods of a fickle river and tectonic fault system. (even with improved knowledge, millions of idiots still build in flood plains???)

    The main problem with modeling is invested interest, wherein some folks become attached to their flawed models, much as hard line Christians take every word of the bible as Gospel.
    The modelers ain't gods, and have always had to work with a small amount of information, and a lot of assumptions. And, some have focused far to much on one causal factor while ignoring others.
    As we learn more about our planet, the models should improve IF and only if the current models are recognized as successive approximations toward a goal, and not lionized as "beyond dispute".

    We are imperfect members of an imperfect species.

    ....................
    Somewhere along this path, we should pause a moment, take a giant step backward, and ask ourselves just what it is that we want of our climate, and why.
    Being as plants comprise over 99% of the biomass of this planet, and are distant cousins, looking to their preferences, and optimum climate conditions seems an obvious approach(maybe not the best approach, and only one of many).
    Disclaimer aside: Let us proceed to look at plants under varying atmospheres. If you deem optimum groath a positive, and are looking into an atmosphere enriched with CO2, then the face studies have done some experiments worth a look............the plants prospered under CO2 enriched atmospheres of 600ppm. The limiting factor was nitrogen for atleast one of their studies.
    What percent of current models adjust for the complexities of plant biomass interaction with anthropogenic atmospheric forcing?
    Which brings us to ssw events.
    but first: What percent of climate models reference ancient stomata size, number, and shapes?
    Is there a consensus on cause and effect of SSW events? There was one, when we had much less data, but now, not so much so.

    The bottom line for science, is that there is no bottom line
    except(maybe)
    ...
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  11. #10  
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    When many(most? all?) are tested by looking into the past, they fail the test. Does this mean that they are rubbish?
    No. It means they need to be changed in some way. That's what modellers do. "Hindcasting" is the standard testing method.
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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  12. #11  
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    Quote Originally Posted by sculptor View Post
    Climate modeling is a darned entertaining attempt to build a map of the earth and atmosphere, then extrapolate expected changes into the future.
    When many(most? all?) are tested by looking into the past, they fail the test. Does this mean that they are rubbish?
    If one looks at early maps of exploration, it becomes obvious that most were flawed. Take those flawed maps, and predict where roads, and towns would build up, then invest in realestate for the long haul? Half of the early "white" settlements along the mississippi river are now gone, washed away by the floods of a fickle river and tectonic fault system. (even with improved knowledge, millions of idiots still build in flood plains???)

    The main problem with modeling is invested interest, wherein some folks become attached to their flawed models, much as hard line Christians take every word of the bible as Gospel.
    The modelers ain't gods, and have always had to work with a small amount of information, and a lot of assumptions. And, some have focused far to much on one causal factor while ignoring others.
    As we learn more about our planet, the models should improve IF and only if the current models are recognized as successive approximations toward a goal, and not lionized as "beyond dispute".

    We are imperfect members of an imperfect species.
    Quite frankly the broad sweeping logical false equivalence and claims that modelers don't recognize shortcomings statements make you look like an idiot. Read the discussion parts of nearly any peer-review climate model result for lots and lots about limitations, concerns and prospective future research including some of the points you make when you aren't ranting.
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  13. #12  
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    I think this might be a good topic to post this just released article.

    Long-Term Climate Warming Trend Sunstained in 2013 - NASA Science
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  14. #13  
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    Quote Originally Posted by Lynx_Fox View Post
    Quote Originally Posted by sculptor View Post
    Climate modeling is a darned entertaining attempt to build a map of the earth and atmosphere, then extrapolate expected changes into the future.
    When many(most? all?) are tested by looking into the past, they fail the test. Does this mean that they are rubbish?
    If one looks at early maps of exploration, it becomes obvious that most were flawed. Take those flawed maps, and predict where roads, and towns would build up, then invest in realestate for the long haul? Half of the early "white" settlements along the mississippi river are now gone, washed away by the floods of a fickle river and tectonic fault system. (even with improved knowledge, millions of idiots still build in flood plains???)

    The main problem with modeling is invested interest, wherein some folks become attached to their flawed models, much as hard line Christians take every word of the bible as Gospel.
    The modelers ain't gods, and have always had to work with a small amount of information, and a lot of assumptions. And, some have focused far to much on one causal factor while ignoring others.
    As we learn more about our planet, the models should improve IF and only if the current models are recognized as successive approximations toward a goal, and not lionized as "beyond dispute".

    We are imperfect members of an imperfect species.
    Quite frankly the broad sweeping logical false equivalence and claims that modelers don't recognize shortcomings statements make you look like an idiot. Read the discussion parts of nearly any peer-review climate model result for lots and lots about limitations, concerns and prospective future research including some of the points you make when you aren't ranting.
    That wasn't meant for climate modelers-----I seriously doubt that any are in here.
    The 2 paragraphs were meant for those who are reading what is posted in here.
    You really should have figgured that out on your own. You may be having a problem with objectivity here?

    As re climate models--please link to one that will(has) accurately predict(ed) the past, against which we may guage it's accuracy.
    As recently as 2012, i pointed out that professor Dr. Julie Brigham Grette and the lake el'gygytgyn crew stated that they couldn't find a single climate model within which fit their field data. They did not state this to disparage climate modeling---in prof Brigham Grette's words: “We’re having trouble explaining all of that data – it provides us with new questions,” Julie said. “That’s more or less the scientific method – once you have some answers, you also get more questions. It’s to be expected.”
    In the intervening months, i've read maybe a dozen discussions of efforts to tweak the extant models to reflect that data.

    I do not despair the effort, much as maps continue to improve by re-examining mistakes, so to I expect the same of all honest efforts of man. In the words of one of my old professors Buckminster Fuller: "The map is not the terrain."
    Or, as I have stated, field data always trumps modeling.

    I stand by my words:
    As we learn more about our planet, the models should improve
    The possibility that we may never have models that will accurately predict the varied forcings does not negate the value in trying to constantly answer the next question.

    Are you up on the findings of the cryosat studies?
    In the three years of data, the arctic sea ice volume has not changed significantly; including the "record" low areas of sea ice coverage, untill(?)the recent 50% rebound(which seems to be indicating asignificant increase in volume). The data is still being analyzed, and has been claimed to indicate quite different results.
    "One of the things we'd noticed in our data was that the volume of ice year-to-year was not varying anything like as much as the ice extent - at least for the years 2010, 2011 and 2012," explained Rachel Tilling from the UK's Nerc Centre for Polar Observation and Modelling (CPOM).
    This must bring into question the previous estimates of arctic sea ice volume based on surface coverage data.
    The CryoSat data is still young, and will need more data collection to significantly impact extant models.
    I feel confident that it will open up new answers and new questions.
    Last edited by sculptor; January 22nd, 2014 at 10:24 PM.
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    Are you up on the findings of the cryosat studies?
    In the three years of data, the arctic sea ice volume has not changed significantly; until the recent 50% rebound(which seems to be indicating a significant increase in volume)
    Here's a graphic representation of volume of Arctic sea ice 1980-2012. (There is no updated version of this product.)

    Even if - and it's doubtful - there's been a 50% increase in sea ice volume between September 2012 and 2013, that would simply get to a volume of just over 5 million cubic kms. That's less than the volume in 2009, nowhere near the historic average of the satellite record. In fact the average is between two and three times that.

    Arctic Sea Ice Volume September Monthly Average By Decade & Year 1980-2012
    This graph divides each calendar decade into 10 "slices", one for each year in that decade. The average September Arctic sea ice volume
    is plotted for each year, moving clockwise around the graph and taking one full decade to complete a circuit. The average volume of sea ice
    for any particular September is represented by that plot's distance from the center of the graph; as shown by the vertical axis, more ice volume
    places the plot farther from the center of the graph, while less ice volume places the plot closer to the center.




    The historic average of Arctic sea ice volume is shown in this graphic. Notice that the 2013 September point is not even within one standard deviation of the average (and it's also more than half a standard deviation below the trend line for these decreasing numbers).


    Fig. 2 Total Arctic sea ice volume from PIOMAS showing the volume of the mean annual cycle, the current year, 2010 (the year of previous September volume minimum), and 2007 (the year of minimum sea ice extent in September). Shaded areas indicate one and two standard deviations from the mean.
    Monthly averaged ice volume for September 2013 was 5,000 km3.

    This value is
    56% lower than the mean over this period,
    70% lower than the maximum in 1979, and
    0.6 standard deviations below the 1979-2013 trend.


    September ice volume was about 1600 km
    3 larger than in September of 2012 and within 500 km3 of the 2010 September ice volume.


    The graphs for anomalies/trend and other details are shown on this page Polar Science Center » PIOMAS Arctic Sea Ice Volume Anomaly

    This must bring into question the previous estimates of arctic sea ice volume based on surface coverage data.
    Do you know how the PIOMAS figures are arrived at? They're certainly not a subset of the extent and area data.
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  16. #15  
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    adelady: One of the interesting things about arctic sea ice volume, is that early estimates were just that:
    Estimates
    .
    The ESA invested no small amount of time, energy, and money on the failed launch of CryoSat 1 and then the successful CryoSat 2 in an attempt to finally have something better than the guestimates of the past. The spokespersons for the CryoSat project have not dismissed the earlier "estimates" but invariably lable them as "estimates". I would suggest that we all keep that in mind when looking at claims of absolute values.

    There is little doubt that the volume of arctic sea ice has been diminishing since the end of the "little ice age", and, even more so with the heavy industrialization and higher tsi values since ww2. The absolute numbers, however remain speculative.
    So, take the estimates for what they are, estimates based on area, and a very few drill and core samples.

    This coming year's data should be very interesting, and hopefully informative.
    And, I sincerely hope that investments into the means of finding more accurate data continue apace.

    From your link:
    Sea Ice Volume is calculated using the Pan-Arctic Ice Ocean Modeling and Assimilation System
    and:
    Sea ice volume is an important climate indicator. It depends on both ice thickness and extent and therefore more directly tied to climate forcing than extent alone. However, Arctic sea ice volume cannot currently be observed continuously.
    and:
    Model improvement is an ongoing research activity at PSC and model upgrades may occur at irregular intervals. When model upgrades occur, the entire time series will be reprocessed and posted.
    more here:
    Polar Science Center » Data

    Models are based on prior information(some of which is innacurate) and will change over time. Meanwhile, they are useful as guides if we always keep in mind that they are in and of themselves, only models.

    Your:
    Even if - and it's doubtful - there's been a 50% increase in sea ice volume between September 2012 and 2013, that would simply get to a volume of just over 5 million cubic kms.
    may be innacurate
    as per the CryoSat people:
    In October 2013, CryoSat measured about 9000 cubic km of sea ice – a notable increase compared to 6000 cubic km in October 2012.
    So, your 5 million cubic kms. may be off by quite a bit----(Their 9k vs your 5m is really odd----so, as time permits, I'll look into this disparity, and crunch some #s. Though I think you a tad biased, I can't recall a time when you've been this innacurate--------------damned curious)

    Models are tricky beasties.

    and:
    Over the last few decades, satellites have shown a downward trend in the area of Arctic Ocean covered by ice. However, the actual volume of sea ice has proven difficult to determine because it moves around and so its thickness can change.
    The shortcoming of CryoSat is that it can only measure to a depth of about 10 meters-----which is (mostly) just fine for sea ice, but leaves something to be desired for land based ice.

    read more at:
    http://www.esa.int/Our_Activities/Ob...rom_record_low

    ...............
    edit:
    ok scratch the 5 million, the error was yours, it should have read 5,000(from your linked and quoted)

    (I ain't throwing stones here---[jesus]-- just seeking a greater understanding)
    Last edited by sculptor; January 23rd, 2014 at 01:47 PM.
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    So, your 5 million cubic kms. may be off by quite a bit----(Their 9k vs your 5m is really odd----so, as time permits, I'll look into this disparity, and crunch some #s. Though I think you a tad biased, I can't recall a time when you've been this innacurate--------------damned curious)
    1. I was using September average figures - not October. There can be huge variations year to year in October depending on how early or late the refreeze begins. September is more reliable as an indicator of end of season melt.
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    still doesn't compute adelady. Please re-read your linked above.

    Meanwhile let's look at averages and deviations therefrom.

    Arctic sea ice extent for December was 12.38 million square kilometers (4.78 million square miles). This is 700,000 square kilometers or 270,300 square miles below the 1981 to 2010 average, making it the 4th lowest December extent in the 36-year satellite data record.
    from: Arctic Sea Ice News and Analysis | Sea ice data updated daily with one-day lag
    When you take the link, you'll notice an "ask us" tab on the right side of the page. The folks at nsidc are really nice(and helpful). If you read their material, and compare it to other's, and have a question, just ask them. If my experiences can be considered the norm, you should get an e-mail response within a day or 2.

    700K sq.km. is just a tad under 6% of the 12.38 million square kilometers quoted.

    So, we're looking at area of arctic sea ice that is a tad over 5% under the 1981-2010 average--------
    Are we expecting too much precision for climate models to be able to predict such a small percentage change in area coverage of arctic sea ice?
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    Are we expecting too much precision for climate models to be able to predict such a small percentage change in area coverage of arctic sea ice?
    Too much precision?

    1. When it comes to the Arctic climatologists are still out of breath running to catch up with the much faster than expected loss of Arctic sea ice. They got a gigantic shock in 2007 - but even then some of them were saying that this was an unusual outlier rather than a continuing trend.

    2. Specific predictions for a specific month/ year about specific features of specific regions anywhere in the world? Not what climate models do.

    Climate models are many things, but one thing they most definitely are not is a large scale version of a weather predicting model. Climatologists are interested in trends.

    Seeing as your reference states that the December extent is "the 4th lowest December extent in the 36-year satellite data record " I'd say that's all you need to show that the trend of continuing loss of sea ice continues and shows no signs of returning to the historic average.
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    You seem to be confusing loss of sea ice area coverage with loss of sea ice volume or loss of total sea ice.

    What accurate measurements of volume we do have, seem to lead to a different conclusion.
    Data collection ain't quite as easy as climate modeling, but needs be done none the less.

    A one year upswing in sea ice volume and area does not guarantee a reversal of a trend, and may be misleading.
    The most important thing to know is what we do not know.
    From an admission of ignorance, we may proceed to acquisition of knowledge.
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    Quote Originally Posted by sculptor View Post
    You seem to be confusing loss of sea ice area coverage with loss of sea ice volume or loss of total sea ice.
    Actually she was pretty specific. If anyone might be confusing things it's you good Sir; but it's hard to tell with you continued tactic of broad brush statements about modeling and what not. I'll it to your good devices to find the dozens of studies about loss of multiyear ice, some of which go back to early US Navy reports as they surveyed where they could poke through the ice when you were a much younger man.

    As it turns out Arctic volume and extend are strongly correlated with each other (fifth figure down here: The Arctic Institute - Center for Circumpolar Security Studies)




    What accurate measurements of volume we do have, seem to lead to a different conclusion.
    No they don't. If anything they closely follow each other with less than complete correlation because volume seems to be dropping faster than extent.
    (See 6th figure)

    Data collection ain't quite as easy as climate modeling, but needs be done none the less.
    They inseparable. I'll belabor this point because a lot of folks seem to miss that almost all natural sciences nowdays are advancing at a remarkable pace because of modeling coupled to observations and physics. To take a simple example, you can't do something as simple at get a station atmospheric pressure without a model of the atmosphere between the station's elevation and sea level, or take a temperature without a model of electrical resistance and temperature by the thermometer, or any of a hundred other examples from simple ones here to using most complex models to check for physical consistency between observations (it's the absolutely best means to check for "bad" data). It might not have been that way when you were younger, but the strong link between observation and modeling for measurement applies to just about all sciences now days--get on board and learn about it instead of taking ignorant broad brush swipes every time you mention models which you time and time and time again demonstrate you don't know anything about.

    A one year upswing in sea ice volume and area does not guarantee a reversal of a trend, and may be misleading. The most important thing to know is what we do not know.
    You know as well as others here that one year' data doesn't mean a trend in anything related to climate. You can't really even start to derive meaningful information till you get to about seven years, and thirty is considered the norm before drawing any conclusions.

    From an admission of ignorance, we may proceed to acquisition of knowledge.
    How ironic.
    Last edited by Lynx_Fox; January 23rd, 2014 at 11:15 PM.
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    You seem to be confusing loss of sea ice area coverage with loss of sea ice volume or loss of total sea ice.
    Me? You're the one who cited variations on sea ice extent "4th lowest December extent in the 36-year satellite data record " even though we were talking about volume at the time. I didn't mention the discrepancy because I didn't think that was the issue - and I was already guilty of using millions instead of thousands for cu. kms. Too used to extent/area discussions I suppose.

    And I'm not sure you're entirely clear on the distinction between sea ice extent and sea ice area anyway. But the definitions/explanations are provided at the NSIDC FAQ so they're always there for your reference.
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  23. #22  
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    Quote Originally Posted by Lynx_Fox View Post
    ...
    What accurate measurements of volume we do have, seem to lead to a different conclusion.
    No they don't. If anything they closely follow each other with less than complete correlation because volume seems to be dropping faster than extent.
    (See 6th figure) ... .
    Isn't it curious that the CryoSat crew has come up with data which may be opposite:

    "One of the things we'd noticed in our data was that the volume of ice year-to-year was not varying anything like as much as the ice extent - at least for the years 2010, 2011 and 2012," explained Rachel Tilling from the UK's Nerc Centre for Polar Observation and Modelling (CPOM).
    Curiouser and curiouser:
    Your linked claims:
    The decline of sea ice volume has been even more prominent than the decline of ice extent
    Granted, CryoSat has only been operational for about 3 years. While data from your linked is older than the latest from CryoSat. And, darn-it, the satelite is already almost 50% disfunctional. It will be close to a miracle if we can get another 3 years of data out of it. I sincerely hope that they are already building it's replacement.

    The CryoSat folks go on to say:
    In October 2013, CryoSat measured about 9000 cubic km of sea ice – a notable increase compared to 6000 cubic km in October 2012.
    Over the last few decades, satellites have shown a downward trend in the area of Arctic Ocean covered by ice. However, the actual volume of sea ice has proven difficult to determine because it moves around and so its thickness can change.
    CryoSat was designed to measure sea-ice thickness across the entire Arctic Ocean, and has allowed scientists, for the first time, to monitor the overall change in volume accurately.
    About 90% of the increase is due to growth of multiyear ice – which survives through more than one summer without melting – with only 10% growth of first year ice. Thick, multiyear ice indicates healthy Arctic sea-ice cover.
    Your linked claims:
    The graph depicts monthly Arctic sea ice volume for 2005-2011 and the monthly averages for 1979-1990 and 1979-2000. The decline of sea ice volume has been most prominent during the months of July-October. In contrast to sea ice extent, however, the decline of sea ice volume over the past decade has been more significant throughout the year.
    While the CryoSat folks think NOT:
    One of the things we'd noticed in our data was that the volume of ice year-to-year was not varying anything like as much as the ice extent - at least for the years 2010, 2011 and 2012
    ..................Is it any wonder that we do not agree?........
    ............
    You're right adelady, I use those words(extent and area) interchangeably. Whereas, they are only approximations of each other. Unfortunately, I am of the age wherein, quite often, I will pause in mid sentence wondering what the next word I intended to say was. Then, I grasp at an approximation, and proceed.
    (sigh)
    ..................
    One thing I've learned recently, is to search for the most recent climate data---------ofttimes not getting to older information.
    Thanks for the links.
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  24. #23  
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    Quote Originally Posted by sculptor View Post
    Quote Originally Posted by Lynx_Fox View Post
    ...
    What accurate measurements of volume we do have, seem to lead to a different conclusion.
    No they don't. If anything they closely follow each other with less than complete correlation because volume seems to be dropping faster than extent.
    (See 6th figure) ... .
    Isn't it curious that the CryoSat crew has come up with data which may be opposite:

    "One of the things we'd noticed in our data was that the volume of ice year-to-year was not varying anything like as much as the ice extent - at least for the years 2010, 2011 and 2012," explained Rachel Tilling from the UK's Nerc Centre for Polar Observation and Modelling (CPOM).
    Curiouser and curiouser:
    Your linked claims:
    The decline of sea ice volume has been even more prominent than the decline of ice extent
    Granted, CryoSat has only been operational for about 3 years. While data from your linked is older than the latest from CryoSat. And, darn-it, the satelite is already almost 50% disfunctional. It will be close to a miracle if we can get another 3 years of data out of it. I sincerely hope that they are already building it's replacement.

    The CryoSat folks go on to say:
    In October 2013, CryoSat measured about 9000 cubic km of sea ice – a notable increase compared to 6000 cubic km in October 2012.
    Over the last few decades, satellites have shown a downward trend in the area of Arctic Ocean covered by ice. However, the actual volume of sea ice has proven difficult to determine because it moves around and so its thickness can change.
    CryoSat was designed to measure sea-ice thickness across the entire Arctic Ocean, and has allowed scientists, for the first time, to monitor the overall change in volume accurately.
    About 90% of the increase is due to growth of multiyear ice – which survives through more than one summer without melting – with only 10% growth of first year ice. Thick, multiyear ice indicates healthy Arctic sea-ice cover.
    Your linked claims:
    The graph depicts monthly Arctic sea ice volume for 2005-2011 and the monthly averages for 1979-1990 and 1979-2000. The decline of sea ice volume has been most prominent during the months of July-October. In contrast to sea ice extent, however, the decline of sea ice volume over the past decade has been more significant throughout the year.
    While the CryoSat folks think NOT:
    One of the things we'd noticed in our data was that the volume of ice year-to-year was not varying anything like as much as the ice extent - at least for the years 2010, 2011 and 2012
    ..................Is it any wonder that we do not agree?........
    ............
    You're right adelady, I use those words(extent and area) interchangeably. Whereas, they are only approximations of each other. Unfortunately, I am of the age wherein, quite often, I will pause in mid sentence wondering what the next word I intended to say was. Then, I grasp at an approximation, and proceed.
    (sigh)
    ..................
    One thing I've learned recently, is to search for the most recent climate data---------ofttimes not getting to older information.
    Thanks for the links.
    Next time read what Cyrosat actually says...not what you would hope they might say taking what they say and trying to extend it to periods of time they weren't referring to.

    "“It’s estimated that there was around 20 000 cubic kilometres of Arctic sea ice each October in the early 1980s, and so today’s minimum still ranks among the lowest of the past 30 years,” said Professor Andrew Shepherd from University College London, a co-author of the study."

    There it is in context for you...not hard to confuse in the least.

    --
    I do hope space agencies continue their support for projects such as Cryosat, despite cheery picking deniers trying to cut them off at every opportunity.
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    Even without your peculiar need to say it, I already mentioned that the Cryosat dada was young, and that it only covered 3 years.

    Your:“
    It’s estimated that there was around 20 000 cubic kilometres of Arctic sea ice each October in the early 1980s, and so today’s minimum still ranks among the lowest of the past 30 years,” said Professor Andrew Shepherd from University College London, a co-author of the study."
    Begins with: It is estimated
    OK?

    I had previously mentioned that the CryoSat folks didn't dismiss the earlier models and estimates, but invariably referred to them as estimates.
    Just where, do you think I got that from?

    You already know that I am biased in favor of field data over models.
    That being said: The CryoSat folks use modeling to interpret their data.
    So much like Pope Francis said: "Who am I to judge?"
    But, then again, looking for disparities in or between data or models, is always of interest.

    Lynx
    really:
    more and more when I read your comments I see some wierd personal animosity.
    When I cut and paste quotes from linked sites, I am just sharing their words, and not "what I [you] would hope they might say"
    I provide the links that you might read context for yourself, and quote the parts I deem "in play" in our current correspondence.

    Please read what I actually posted.
    .................................................. ......
    Your linked didn't even agree with CryoSats volume data (for the same time period).
    That is the sort of anomoly/disparity I would actually wish to discuss.

    Where do we go from here?
    Last edited by sculptor; January 24th, 2014 at 02:30 PM.
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    Quote Originally Posted by sculptor View Post
    Even without your peculiar need to say it, I already mentioned that the Cryosat dada was young, and that it only covered 3 years.

    Your:“
    It’s estimated that there was around 20 000 cubic kilometres of Arctic sea ice each October in the early 1980s, and so today’s minimum still ranks among the lowest of the past 30 years,” said Professor Andrew Shepherd from University College London, a co-author of the study."
    Begins with: It is estimated
    OK?
    This is your standard cop out when ever something gets published that doesn't' fit into your brain housing group. EVERYTHING is estimated, and most of it in recent natural sciences affirmed by hard physics-based models.

    You already know that I am biased in favor of field data over models.
    I fully get that...WE ALL ARE. What you completely fail to seem to understand is even the simplest field data, is in large part meaningless in complex systems until it is put into physical models--until that time is isn't information. Field data, modeling and information are inseparable.
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    You're right adelady, I use those words(extent and area) interchangeably. Whereas, they are only approximations of each other.
    No they're not. The FAQ at NSIDC gives as good a description as any.

    What is the difference between sea ice area and extent?


    Area and extent are different measures and give scientists slightly different information. Some organizations, including Cryosphere Today, report ice area; NSIDC primarily reports ice extent. Extent is always a larger number than area, and there are pros and cons associated with each method.


    A simplified way to think of extent versus area is to imagine a slice of swiss cheese. Extent would be a measure of the edges of the slice of cheese and all of the space inside it. Area would be the measure of where there is cheese only, not including the holes. That is why if you compare extent and area in the same time period, extent is always bigger. A more precise explanation of extent versus area gets more complicated.
    ..........

    You can read the rest at Frequently Asked Questions on Arctic sea ice | Arctic Sea Ice News and Analysis
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    Read the "Data and Methodology" section of this paper Sculptor: http://psc.apl.washington.edu/zhang/...l_grl50193.pdf

    You should be able to distinquish over a dozen estimates, parameterizations (simple models), and comparisons to other estimation methods as well as complex models. Most of the other estimates built on their own multi-tiered set of estimates to refine their own outputs (look at the references). Like pretty much all natural sciences, the entire scientific progress is built on estimations, each with their own strengths and weaknesses depending on what it's being used for.
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