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Comments 97701 to 97750:
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Gordon1368 at 06:32 AM on 25 January 2011A Flanner in the Works for Snow and Ice
Gimme an A! Gimme a G! Gimme a W! What's that spell? AGW!!! AGW!!! AGW!!! Gooooooooo AGW!!! Yes, i am pro-AGW, it's my team, what can i say? I know it will make my life miserable, and ruin my children and maybe kill my grandchildren, but it's my side, and I am a loyal fan. I confess to morbid fascination with the declining Arctic sea ice. It's like watching a horrible wreck in slow motion, hard to believe it is happening, yet getting increasingly impossible to deny. But that other side doesn't give up! The Denialists! I hate their team! They can look at objective evidence and strongly Deny it all, first saying "It's not happening" and as the evidence that it is happening mounts, they cheer, "It's all natural!" and "It's a good thing!" I know my side will win though, and that makes me feel.... very very scared. (sorry to be sooo off topic and unscientific, fully understanding if this is deleted by the moderator) -
villabolo at 06:20 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
Rhetorically challenged? Try: Weather is local and brief; Climate is global and long lasting. Weather is the part; Climate is the whole thing. Weather is detailed and can be predicted accurately, within a week, 90% of the time. Climate is broad and basic and can be predicted adequately decades ahead. Climatologists may not be able to tell you the exact temperature or whether it rained or not in your neighborhood on June 1st 10,000 B.C.; but they can tell you if the general conditions where wet or dry; hot or cold. -
NickD at 05:55 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
As we say where I live, if you don't like the weather just wait 15 minutes, it will change. A 12F change in a day is not newsworthy, other than the few minutes spent on the weather forecast on the nightly news. -
Albatross at 05:29 AM on 25 January 2011The Climate Show #5: Green roofs and Brisbane floods
Camburn @16, "One thing I have noted is the seemingly absense of error bars in the papers. It is very hard to draw conclusions without those present." That is a generalized statement, and I can only assume it applies to the Allan et al. (2010) paper. If so, you then need to look at the data in their Table 1 (you can view the PDF by clicking on the PDF hyperlink below the abstract) which does in fact include 95% confidence intervals (i.e., error bars) for the satellite data, GPCP data and modelling data. Regardless, Zhang et al. (2007) used observed gauge data: "We used monthly precipitation observations over global land areas from the most recent version of the Global Historical Climatology Network (GHCN) to analyse precipitation trends in two twentieth century periods". "Our best estimate of the response to anthropogenic forcing suggests (Fig. 1b) that anthropogenic forcing has contributed approximately 50–85% (5–95% uncertainty) of the observed 1925–1999 trend in annual total land precipitation between 40 N and 70 N(62 mm per century), 20–40% of the observed drying trend in the northern subtropics and tropics (0 to 30 N; a decrease of 98 mm per century) and most (75–120%) of the moistening trend in the southern tropics and subtropics (0 to 30 S; 8 mm per century)." Note the ranges (i.e., uncertainty ranges). And note the impact on the S. Hemisphere tropics and subtropics have been affected. Camburn, you seem to be seeking out excuses to convince yourself that AGW is not happening and/or that the consequences in many cases are not going to be unpleasant. Feel free to seek out excuses, you are after all entitled you your opinion and interpretation of the facts, but you are not entitled to your own facts. The fact that we can already discern a notable impact on the hydrological cycle from the warming is very telling and not at all reassuring. Consider this paper by Lenderink and Meijgaard (2008, Nature): "Here, we analyse a 99-year record of hourly precipitation observations from De Bilt, the Netherlands, and find that one-hour precipitation extremes increase twice as fast with rising temperatures as expected from the Clausius–Clapeyron relation when daily mean temperatures exceed 12 °C" Only one location, but the physics apply to your part of the world too. -
thepoodlebites at 05:17 AM on 25 January 2011It's Pacific Decadal Oscillation
#67 Let's say (for the sake of argument) that the Jan. 2011 UAH anomaly is -0.2 C, a good possibility. The Dec. 2010 UAH anomaly was +0.18 C, a fact that is not in dispute, I hope. From the plot we can see that the monthly anomaly would then be back down to near Jan. 2008 (-0.3 C). Actually, that would bring us all the way back to near the beginning of the satellite record, June 1979 (-0.2 C). And remember, the peaks in 1998 and 2010 were from El Nino warming. The latest SST's still show La Nina. These are monthly means, whether the 12-month running mean drops to near zero will be determined in the coming months. Continued warming would mean higher highs and higher lows. Yeah, I'd say it's a wipe-out, just like in 2008. -
Ron Crouch at 04:58 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
#15 notcynical "Wow, 7C is 12.8F; 80F vs 92.6F, 20F vs 32.6F are not worth noting?" I you call a notation on a web page stating that there is an abnormal temperature trend as being noteworthy. Take London Canada for instance. The overnight temperatures are expected to rise by 19.8oC (35.64oF) in a 24 hour period. You won't find any hoopla in the media about it though. It's just simple weather variability. A cold front moved into the region and now it's being pushed out. Big deal. Now if the temperature were to change from -22.8oC to 22.80C in a 24 hour period, then it might be noteworthy. -
Paul D at 04:52 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
Dikran@24 I meant scale as perceived by a human. eg. A person only experiences a weather event at a very localised level and that can seem highly erratic. One can be walking along and one minute you are in a shower, the next you aren't. This localisation and detail is impossible to predict, but at the greater scale (say) from space, the weather event may seem more uniform and conforming to obvious turbulent behaviour. It's like picking up a lump of wood, it has some obvious characteristics that are well known and common to all lumps of wood, but go down to the atomic scale and things are a lot different. Molecules are moving and vibrating and it would be difficult to equate what was happening in molecule land with the formation of tree rings etc. In the analogy, a typical Joe or Jane is living with the atoms, not seeing the bigger picture. They are just interested in buying a reliable car and knowing what the weather will be like in the afternoon. Probably should have explained in more detail. My comment was really to do with peoples perceptions. The vast majority of people think on a basic level on a daily basis. I happily watch science on TV. But the vast majority would prefer to watch a soap, or reality TV. If you start talking about science, you just get a blank face or a frown! -
Marvin Gardens at 04:27 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
Great analogy about the pool and the hose and the waves. Couldn't we just as easily say the input from the hose was increased radiation from solar activity? More record highs than lows provides an increasing average which is exactly what one would expect from a warming climate. -
Albatross at 04:15 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
LandyJim @9, "Many climate models are presnted to the public as fact, in 50 years the planet WILL be 7°C warmer, the ice-caps WILL have melted and the ocean WILL be 7m deeper." I'm afraid that this statement is false, at least how it pertains to the science and the IPCC and the governments which signed off on the IPCC reports. Please note the following statement from the IPCC: "An expert assessment based on the combination of available constraints from observations (assessed in Chapter 9) and the strength of known feedbacks simulated in the models used to produce the climate change projections in this chapter indicates that the equilibrium global mean SAT warming for a doubling of atmospheric carbon dioxide (CO2), or ‘equilibrium climate sensitivity’, is likely to lie in the range 2°C to 4.5°C, with a most likely value of about 3°C. Equilibrium climate sensitivity is very likely larger than 1.5°C. For fundamental physical reasons, as well as data limitations, values substantially higher than 4.5°C still cannot be excluded, but agreement with observations and proxy data is generally worse for those high values than for values in the 2°C to 4.5°C range. The ‘transient climate response’ (TCR, defined as the globally averaged SAT change at the time of CO2 doubling in the 1% yr–1 transient CO2 increase experiment) is better constrained than equilibrium climate sensitivity. The TCR is very likely larger than 1°C and very unlikely greater than 3°C based on climate models, in agreement with constraints from the observed surface warming." [IPCC AR4 WGI page 749] Now compare that with what WUWT says, just one example but there are many more: "New paper from Lindzen demonstrates low climate sensitivity with observational data" [here] Anyhow, we are getting way off topic here... -
Albatross at 04:05 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
An excellent analogy John. I will be sure to use that in the future. Sure beats me trying to explain to people that weather is an initial value/conditions "problem", while predicting climate is a boundary forcing "problem". But as you note it is a red herring and an appeal to emotion. Yet another trick employed by "skeptics" and contrarians. The sad truth is that many weather agencies do not provide the public verification statistics, or make them easily available. So the misconception has been that forecasts are not good-- using anecdotal evidence to validate forecasts is absolutely awful. The UK Met office does an excellent job of communicating their verification stats to the public. -
nealjking at 03:56 AM on 25 January 2011Oceans are cooling
HumanityRules, #54: To get anything quantitative, one would have to specify: - the magnitude of the driving temperature variation at each frequency - take into account the very complicated mixing of layers (one thing I can see from the graphs is that different things are happening at different latitudes; that means that water at different layers are mixing) - take into account the initial conditions. In the end, the best thing to do is to model the system numerically: including both the heat flow and the very complicated water flow. All I'm using this set of frequency-specific analytical solutions for is to understand a few qualitative features: i.e., why the long-period oscillation has more "thermal inertia" than the short-period oscillations. It helps the intuition a bit, but isn't good for making very detailed comparisons. -
Dikran Marsupial at 03:55 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
The Ville Actually scale isn't nearly as much of a problem as you might think. In a Taylor series expansion, the more terms you add, the more accurate the approximation to reality, even though to get a completely accurate model you often need an infinite series. But that doesn't mean that even very crude Taylor series expansions with only a couple of terms don't provide a useful approximation. Similarly for GCMs, the higher the spatial and temporal resolution (the more "scale" you include), you become able to make more detailed projections on finer spatial and temporal scales. It isn't a matter of you can model climate or you can't, it is a matter of how accurate and how refined the projections you can make. Using current technology, GCMs work well at global and regional scales (e.g. continents), but don't have the resolution to make useful projections on sub-regional or national scales. So the "scale problem" is not a problem as long as the appropriate caveats are placed on the projections (and scientists being scientists, the papers are generally full of such caveats). As GEP Box (famous statistician - if that isn't a contradiction) said "all models are wrong - but some are useful". -
Phila at 03:43 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
Please note the unnecessary apostrophe in the title of this post. -
Phila at 03:26 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
I used to use a gambling analogy to explain this to people: you can't predict the result of an individual pull on a slot machine, but you know the results will conform with the house odds over the longer term. Unfortunately, I've found that most of the people who find this "skeptical" argument compelling also don't quite get the concept of house odds. They're more likely to think about outcomes in terms of fate. Which is not all that different from "skeptics," really; they're both very bad gamblers, IMO, with a strong faith in last-minute miracles and a strong tendency to downplay their losses. -
michael sweet at 03:09 AM on 25 January 2011Monckton Myth #6: Global Sea Ice
GC: The Copenhaen Diagnosis is not produced by the IPCC. If you want to slander someone in the future please refer to the correct people. The jury is still out on whether the Arctic ice is collapsing or not. The ice volume continues to rapidly decline. Estimates of when the Arctic will be ice free have gone from 2050-2100 in the IPCC report (written in 2007) to 2014-2040 now, only three years later. I would call ice free by 2020 "a dramatic decrease in Arctic ice" that was foreseen in 2007. It is obvious from the data that the IPCC was much too conservative!! Why aren't you complaining about that? We can compare notes again in September to see how the melt goes this year. Cite a scientist who claimed that the Arctic would be ice free before 2015. Find a consensus report that gives a date before 2020. Stop making wild strawman arguments about NSIDC and IPCC being alarmist. Deniers always make these type of wild argument so they can knock down the strawman. -
MarkR at 02:56 AM on 25 January 2011A Flanner in the Works for Snow and Ice calculations
Well, by definition the calculations are for an equilibrium sensitivity (this is true and physical), but what we don't know is whether the value of the feedback parameter we measure now will be the same by the time we reach equilibrium. Which is what your second paragraph is saying! I worded my post saying that if the current measurements are representative of what we ultimately get then this means a big boost to climate sensitivity. But I also tried to make it clear that perhaps it's a case of things just melting more quickly than we expected to begin with and maybe albedo feedback will 'slow down' and head back to model values. All the paper shows is that models underestimate what we expect to see so far, we can probably be confident about that (but ofc we need to see further work for confirmation!) - but more work is needed to have greater confidence that we've underestimated the long term feedback. -
snowhare at 02:47 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
@15 "" Wow, 7C is 12.8F; 80F vs 92.6F, 20F vs 32.6F are not worth noting? The whole post lost some credibility with that statement." You are making an argument without substance. I just pulled the daily average records for Nephi, Utah (station 426135 in the Historical Climatology Network - a fairly random pick), wrote a small script to compute the absolute difference between successive days (excluding dates with missing data) and of the 23972 date pairs, 1302 of them had *at least* 12F difference. That is an average of about 1.6 times per month. Even limiting it to 13F, we get 938 instances for an average of a bit over 1.1 times/month. Something that happens, on average, more than once a month is not unusual enough to warrant special note. As for the 'One question is why has the pool level not gone up much, if at all, in the last 10 years' comment, that belongs over in the Did global warming stop in 1998? thread. -
Ron Crouch at 02:43 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
Further where did you happen to get that models are predicting this in the first place Jim? -
Ron Crouch at 02:39 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
#9 LandyJim "in 50 years the planet WILL be 7°C warmer, the ice-caps WILL have melted and the ocean WILL be 7m deeper." Oh come now. I myself might believe that abrupt climate change might be something that we face, but I don't make rash statements like this. Unless you can substantiate this claim, it amounts nothing less than "scaremongering". -
Sasquatch at 01:53 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
Good point, Notcynical. As a high school student, we were shone An Inconvenient Truth by several well-meaning teachers. The result was polarizing to say the least. The movie was alarmist and non-scientific. Are there any charts available which plot the rise and fall of other greenhouse gases?Moderator Response: You are incorrect. See "Al Gore got it wrong." Regarding other GHGes, see "CO2 only causes 35% of global warming," "It’s CFCs," "It’s ozone," "CO2 is not the only driver of climate," "Water vapor is the most powerful greenhouse gas," "Humidity is falling," and "It’s methane." -
Pete Dunkelberg at 01:45 AM on 25 January 2011A Flanner in the Works for Snow and Ice calculations
Thanks Mark. I see that you have a good point. However it is a bit brash to say that certain symbols "by definition" represent an actual physical quantity. Consider this possible physical process: spring now comes earlier snow melts and becomes water wet ground reflects less light than dry ground (I presume here) A century later, spring comes much earlier. Then, by the time each spring when the ground is now wet with melt water, it has dried. Albedo goes back to dry ground albedo. (The wet ground period comes earlier when the sun is a lower angle). Result: equilibrium sensitivity is lower than what you project here. -
Kevin C at 01:42 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
I've met this one. It can actually be addressed without getting into chaos theory by looking at the structure of the formal argument... 1. Weather in unpredicatable (beyond x days...) 2. Given that weather is unpredictable, it necessarily follows that climate is unpredictable. What is climate? Roughly, the statistics of weather. Thus: 1. Weather in unpredicatable (beyond x days...) 2. Given that weather is unpredictable, it necessarily follows that the statistics of weather are unpredictable. The argument falls if either premise is incorrect. The second premise takes the form: "Given that X is unpredictable, it necessarily follows that the statistics of X are unpredictable." Which can be falsified by example: Given that dice are unpredictable, it necessarily follows that the statistics of dice are unpredictable. Given that lottery machines are unpredictable, it necessarily follows that the statistics of lottery machines are unpredictable. Given that crimes are unpredictable, it necessarily follows that the statistics of crime are unpredictable. Given that hard disk failures are unpredictable, it necessarily follows that the statistics of hard disk failures are unpredictable. -
DSL at 01:38 AM on 25 January 2011A Flanner in the Works for Snow and Ice
There's that term again -- "pro-AGW." What a weird thing to label people who would probably give their right and left arms to keep the climate as stable as it has been for the last several thousand years. -
Kevin C at 01:30 AM on 25 January 2011A Quick and Dirty Analysis of GHCN Surface Temperature Data
I'm afraid I think I found a mistake. I was trying to reproduce your result in python and failing. Eventually I had to instrument your code and mine, and eventually I found out the mistake. You use characters 3-7 of the station id as a key, I use 0-10. The documentation isn't very clear, but here's what I get from it and from various blogs: - The first 3 characters a country code, irrelevent for our case because it can be deduced from the rest of the station ID. So omitting this is fine. - The next 5 chars are the WMO station code. - The final 3 are the imod code. IIUC this is used for stations which so not have a WMO code. The station is given the code of the nearest WMO station, which may be a substantial distance away, plus a non-zero imod code to distinguish it. The problem is that the imod!=0 stations are separate stations. By ignoring the imod code, you merge all of these stations into the single WMO station. In the case of disjoint records, the resulting record contains both (but only gets a single baseline), in the case of overlapping records, the last overwrites the others. Examples include: 68262: 14168262000 14168262001 44373: 21544373000 21544373002 72211: 42572211001 42572211002 42572211003 72214: 42572214000 42572214001 72217: 42572217001 42572217002 42572217004 72672: 42572672000 42572672001 42572672002 42572672003 72671: 42572671001 42572671002 42572671003 42572671004 42572671005 42572671006 72670: 42572670001 42572670003 42572670004 42572670005 42572670006 42572670007 42572670008 42572670009 42572670010 42572670011 42572670012 So I changed this in my program and verified I could reproduce your results. Here's my 2 graphs plus yours:http://postimage.org/image/35hd6ufc4/ Note that with 5/8 char station IDs I match your results pretty well. With 11 char IDs the results are rather different. What threw me for a while is that the full ID gives apparently worse results, so I assumed at first that it was my mistake. In particular, it shows a much larger hump around 1935. But looking at the station IDs, it is clear that a lot of the imod codes are in the US (country=425). I think what your code is doing is merging a lot of US stations, and thus reducing the overweighting of US data arising from the over-representation of US stations in the data. The correct solution of course is geographical binning (or some equivalent method) to deal with this over-representation. So I implemented that in my version. Here's what I get, along with NASA's resutls:
http://postimage.org/image/2f5tftz9g/ Note that the difference between the 5 and 11 char versions is now reduced, and apart from the sparse early data the curves follow the gistemp data quite well, including the 1935 period. I'm still not 100% certain, so I'm hoping someone more knowledgeable will comment, but at the moment it seems to me that the 11 character approach is the correct one.
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Pete Dunkelberg at 01:24 AM on 25 January 2011A Flanner in the Works for Snow and Ice
Here is a pdf file of the slides from a presentation of the paper. MarkR, I appreciate your comments. Since you mention textbooks, why not name and briefly describe a couple? -
notcynical at 01:13 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
"A change in temperature of 7º Celsius from one day to the next is barely worth noting when you are discussing weather." Wow, 7C is 12.8F; 80F vs 92.6F, 20F vs 32.6F are not worth noting? The whole post lost some credibility with that statement. The pool analogy is a good one... up to a point. One question is why has the pool level not gone up much, if at all, in the last 10 years even though the water has been flowing in at an ever increasing rate. This is not to deny that water is flowing into the pool, just that things are not so simple, and that there are still some things we do not have a good explanation for. -
Eric (skeptic) at 01:00 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
The example of 7 degrees change in average should perhaps be supplemented with a sentence on the length of time versus the type of prediction. The GAT just dropped 0.1 degrees in two days which could not have been predicted a week ago. Last year a rise of 0.3 degrees in a month was only as predictable as the El Nino with a few months skill at best. At the same time that we are inflicted with unpredictable day-to-day changes in albedo, week-to-week changes in atmospheric circulation, month-to-month in ocean circulation, the GAT plods upward decade-to-decade reflecting AGW and (to various debatable extents, long term cycles). Prediction of AGW is deterministic and can be greatly helped with empirical studies (e.g. measurements of actual OLR changes from feedback processes). The greatest uncertaintly in AGW predictions is the changes in weather itself, e.g., will AO become more positive or more negative (or cycle between both extremes or neither)? Temperature data source http://discover.itsc.uah.edu/amsutemps/data/amsu_daily_85N85S_ch05.r002.txt -
muoncounter at 00:36 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
#9: "Many climate models are presnted to the public as fact" On the contrary, I find the language of climate models overly timid. See the thread 'IPCC is alarmist' for examples of consistent use of conditional language. "When climate change is presented to the public as predictions instead of facts, then there may be less and less arguments" Wishful thinking at best. The primary tactic of the 'argument' community is to create doubt via making noise. See Oreskes' book for an exceptionally well-documented history of this. -
TimTheToolMan at 00:14 AM on 25 January 2011The 2010 Climate B.S.* of the Year Award
dehogza writes : "Lindzen testified to Congress that it's not really warming, and that supposed warming is due to modern thermometers that magically records transient warmth more efficiently than older mercury-based thermometers, while at the same time not being more sensitive to transient colder events." Would you care to speculate the conditions surrounding those "transient cold events" that might tend to effect the daily minimum for me? -
JMurphy at 00:12 AM on 25 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
LandyJim wrote : "Many climate models are presnted to the public as fact, in 50 years the planet WILL be 7°C warmer, the ice-caps WILL have melted and the ocean WILL be 7m deeper.. This is BAD science, or at least the reporting of it." Sounds more like BAD reporting to me, or do you have actual examples ? LandyJim also wrote : "When climate change is presented to the public as predictions instead of facts, then there may be less and less arguments raised against it." The former is currently the way climate change is reported by the people involved in studying it - just have a look at the last IPCC report. The latter will never be possible with a certain section of society, because they don't want to accept the facts. Unfortunately, enough of them have enough influence to impede progress : that is the real problem. -
Paul D at 23:32 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
Dikran, maybe weather is somewhat chaotic, but the causes of it aren't. Same goes for climate. Excluding unpredictable events such as something big hitting the Earth, the main inputs that cause weather are well known, or known well enough. Those inputs cause well known behaviours globally. There are actually more knowns than there are unknowns (beginning to sound like Rumsfeld!). But the ultimate outcomes may be less predictable. In some respects it is the scale that is a problem. Most people probably don't realise that the machines and equipment they use, only work reliably because someone has worked out the statistical probability of it failing and using components that minimise the probability of the product failing. All they see is a product that works for x years. They don't think that reliability is 'engineered' and they just get the engineered result. They then expect the same to be done with a system that is not engineered and have expectations that go beyond what is practical. I think half the issue is the huge expectations people have today. -
MarkR at 23:21 PM on 24 January 2011A Flanner in the Works for Snow and Ice
RE: 19 LandyJim To me this method makes perfect sense, based entirely on how feedbacks are defined and by looking at the heat flow in the system. If you go to my notes (linked to twice in the article), I give the relevant equations. If you don't follow the importance of this then introductory climate science textbooks tend to include it and it makes a lot more sense. If you can find flaws in this, then you have the makings of a wonderful, groundbreaking paper. :) We have a world where there are different feedbacks. We are interested in temperature's effect on them, and then their effect on radiation which can be converted to an effect on temperature. By considering the feedback parameter dF/da.da/dT you get the parameter a's effect on F given a change in T. This, from mathematical definitions allows you to determine the ultimate climate sensitivity assuming the feedback remains close to its measured value. By measuring it in observations, what you are doing is measuring feedback a1 as a1(F,T,a2,...,aN) i.e. it is a function of the (N-1) other feedbacks. But by taking observations, you are measuring it at specific values of a2,...,aN so their cross effects are included. You then measure the other feedbacks, e.g. clouds might be a2(F,T,a1,a3,...,aN) and that fully includes the coupled effects to the other feedbacks as well. So in each individual measurement, you don't need to calculate the other ones, you just need to independently measure them all. This is why Flanner's results are useful even though they don't discuss clouds in much detail. It's not scaremongering, it's just what the real world has done, which has been measured and reported on by a group of scientists who have a very useful theoretical tool that allows them to put it as a single value that is easy to compare and handle and very physically relevant. -
Dikran Marsupial at 22:58 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
A thought experiment based on a double pendulum is the best way of explaining this canard that I have been able to come up with. Weather is chaotic, and inherently unpredictable (beyond a short prediction horizon) but that doesn't mean the long term statistical properties of the weather (a.k.a. climate) are chaotic or unpredictable. Likewise the the exact path followed by a double pendulum can't be predicted beyond a short prediction horizon, but you can make predictions about its statistical behaviour if you for example you stuck a large magnet to one side (follow the link for pretty picture and discussion of simulation based prediction). -
LandyJim at 22:31 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
I agree there is a clear lack of understanding in the public domain of the difference between weather forecasting and climate predictions. Governments are actually to blame for this, but so is the science community because of statements that are made. Many climate models are presnted to the public as fact, in 50 years the planet WILL be 7°C warmer, the ice-caps WILL have melted and the ocean WILL be 7m deeper.. This is BAD science, or at least the reporting of it. It should be worded so that people understand this is a prediction of what MIGHT happen if things stay as they are. The problem is we cannot predict what will happen this time tomorrow, let alone in 50 years. A major series of volcanic events can alter the weather very rapidly, many of the events predicted may have effects that have not been foreseen or may not be as severe as people and models estimate. The truth is we understand the climate and the weather very poorly, Yes reasonable predictions can be made over a few days to a week, but this is based as much on experience as calculations. The atmosphere of our planet is highly complicated, the interactions it undergoes within it and with external influences is immense, and we have only scratched the surface in our understanding. Models may be getting better, the information we put in is of a higher quality, but there is still those unknowns, the uncertainties and the unknowable. When climate change is presented to the public as predictions instead of facts, then there may be less and less arguments raised against it. -
LandyJim at 22:16 PM on 24 January 2011A Flanner in the Works for Snow and Ice
@Geln Tamblyn #11 That criticism seems to me to be based on a rather simplistic view of how science works Jim. Much of science is based on researchers looking at small parts of a puzzle. This spurs others to investigate other parts. And what a research team looks at depends on their backgrounds, resources, budegt etc. To criticise some work because it didn't try to look at all aspects seems unfair. Others will do that over time. This paper is showing one result. Others will no doubt look into other aspects subsequent to this. Patience Jim Glen, I understand how science works very well and in general for how science operates in the modern world your comments are correct, but there is also a responsibility to researchers to ensure that their papers are as complete at possible. MarkR has highlighted the minuscule cloud data in the article, but it does not stack up as it is incomplete, perhaps in haste I worded my original post in a misleading way...(Just going to hospital with 9 month old son..). For the record, I am not devoid of a science background. I am an Electrical Engineer and I hold an Honours Degree in Astronomy, currently, as I said in a post in the Hurricane thread, I am working on Hurricane data to ascertain what if any changes have occurred there and as an aside I am researching rainfall records from all nations who have rivers feeding the Atlantic and all inter-related data on this, including sea state locally, temperature, salinity etc. As I have said, I do not accept many of the Pro AGW arguments, but that does not mean I will simply sit on my hands..it will simply take me time to compile all the data I need to come to an independent conclusion about a few aspects of this that simply do not sit straight with me as they do not make sense. -
sime at 22:09 PM on 24 January 2011Monckton Myth #6: Global Sea Ice
If this keeps up there won't be any ice in a few years never mind a few decades... http://climateprogress.org/2011/01/23/canada-mildness-high-presure-record-ostro-global-warming/ "The largest anomalies here exceed 21°C (37.8°F) above average, which are very large values to be sustained for an entire month." Abrupt climate change perhaps? Here comes the boxer, that we trained so well! -
alexaraujoc at 21:13 PM on 24 January 2011Hockey stick is broken
I would like to call your attention to the most recent temperature reconstruction, which was published in Science this month. The paper entitled "2500 Years of European Climate Variability and Human Susceptibility" by Büntgen et al. actually suggests that the current warming has no parallel in the last 2500 years. ABSTRACT Climate variations have influenced the agricultural productivity, health risk, and conflict level of preindustrial societies. Discrimination between environmental and anthropogenic impacts on past civilizations, however, remains difficult because of the paucity of high-resolution palaeoclimatic evidence. Here, we present tree ring–based reconstructions of Central European summer precipitation and temperature variability over the past 2500 years. Recent warming is unprecedented, but modern hydroclimatic variations may have at times been exceeded in magnitude and duration. Wet and warm summers occurred during periods of Roman and medieval prosperity. Increased climate variability from ~AD 250 to 600 coincided with the demise of the Western Roman Empire and the turmoil of the Migration Period. Historical circumstances may challenge recent political and fiscal reluctance to mitigate projected climate change. -
MarkR at 21:05 PM on 24 January 2011A Flanner in the Works for Snow and Ice
#9 LandyJim: the paper specifically considers clouds. e.g. at the top of the right hand column of text on the second page. It is an observational set so implicitly it includes non T & non F interactions with cloud, vapour etc which is very useful if you go to the calculations attachment and follow what's going on there. You see that feedbacks can be decomposed into independent, measurable values and the feedback equation fully includes their interaction with each other. The method used by Flanner makes no assumptions about ice->water, I have no idea where you got that idea from! To determine the feedback parameter for albedo changes you don't need to know much about clouds. But to determine the total global warming you need to know all the individual feedback parameters quite well. Other papers have looked at other feedbacks (e.g. Dessler '08/'10; Chung '09; Lauer '10 spring to mind). -
MarkR at 20:54 PM on 24 January 2011A Flanner in the Works for Snow and Ice
#6: krab, I tried to be clear by stating that it was their contributions to the Northern Hemisphere. They concentrated on the NH to do a like-for-like comparison between models and the data they had. To convert to global is easily done assuming models=truth for the southern hemisphere, but doesn't tell you the scale of the mismatch between observations vs models. -
Paul D at 20:53 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
This sort of conversation is the type one would have with another bus user whilst waiting for a bus. Those that insist on driving and never use public transport, probably avoid this type of reality and only encounter it in the comments of a newspaper web site. There isn't a lot that can change the intellectual abilities of the people you talk to, what is done, is done! But what you can do is spend some time explaining the issue in terms that they might understand. There is no guarantee that even if the person you were talking to was better educated, that they would be more inclined to agree with you. See this report: http://environmentalresearchweb.org/cws/article/news/44825 -
les at 20:49 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
small suggestion, the sentence: "However, slight errors in initial conditions make a forecast beyond two weeks nearly impossible." might be: "However, slight errors in initial conditions make a weather forecast beyond two weeks nearly impossible." very pedantic, I know. But then the use of cherry-picking and selective quotation by some, calls for that. -
MarkR at 20:40 PM on 24 January 2011A Flanner in the Works for Snow and Ice calculations
These calculations are by definition for the equilibrium climate sensitivity. That's why I said at the bottom 'if the current pattern holds...' So if this relationship between temperature-albedo and albedo-flux holds, then you would expect a boost of 20% to climate sensitivity if your original estimate was 3 C and all other feedbacks retain their properties linearly. This sounds a bit weird, but I'm thinking of doing a post at some point to try and make it clearer. In effect the feedbacks 'reinforce each other' - the extra energy trapped by your change in albedo is 'recycled' multiple times by the enhanced greenhouse effect etc. -
HumanityRules at 20:36 PM on 24 January 2011Oceans are cooling
52 nealjking From all that is it possible to put absolute values on abyssal warming to forcings of different magnitudes over different time periods? The reason I ask is there seems to be some subjective descriptions of different time periods as being long and short.
was used to suggest forcing over only 1-2 decades have had significant impacts on abyssal warming. While the discussion around this image.
suggests volcanic forcings (4-5 years) fall into the category of forcings that only have a temporary effect on OHC at the top level, similar to season variation. There seems to be some convinient placing of different forcing into particular categories in order to make wider points about what is going on here.
I'm interested to know if the conclusions about all these different forcings can be resolved by a consistent description of heat transfer in the oceans?
-
Tom Curtis at 20:04 PM on 24 January 2011A Flanner in the Works for Snow and Ice
Pete Dunkelberg, thanks (sort of :) ) for picking up my slip. The comments regarding sensitivity were in responce to Bodo @5. -
MattJ at 19:01 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
Failing to understand the difference between short term and long term averages and their predictability is a common failure among the 'innumerate'. Innumeracy is as big a problem as illiteracy -- if not more so, since people instinctively recognize the latter as bad but tolerate the former all too easily. -
adelady at 18:58 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
You want accurate. I'll give you accurate Followed this one from Hot Topic (I think). I'm keeping it foreverandever. -
Pete Dunkelberg at 18:15 PM on 24 January 2011A Flanner in the Works for Snow and Ice calculations
I agree with Steve Bloom: something is not right here. I think you may have mixed transient response with equilibrium sensitivity. This is quite a worthwhile discussion all the same. -
Pete Dunkelberg at 17:56 PM on 24 January 2011A Flanner in the Works for Snow and Ice
Tom Curtis, you arrive at a good conclusion despite a slight typo: "The paper finds a much greater albedo rise (sic)...." but I don't think sensitivity belongs in this discussion (but I don't have the paper). Perhaps a slight slip in the OP set you off. I think this is another indication that the "slow" feedbacks are not cooperating by being slow. They are are not influenced by what we call them. -
Glenn Tamblyn at 17:45 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
I want some of what he was smoking... -
villabolo at 17:30 PM on 24 January 2011Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
I guess climatologists have been perceived as...
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