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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 80751 to 80800:

  1. 2010 - 2011: Earth's most extreme weather since 1816?
    Eric the Red @170, you also ignore the negative PDO index from 1960 to 1970 but low rainfall, and the period from 1980 to 1990 with positive PDO index and high rainfall. Adding those two periods to the early twentieth century you have around 50 years in which there is no correlation, or the opposite correlation to that predicted. It doesn't correlate well in the 2000's either. Establishing a correlation over fifty years and then asking me to ignore the other sixty because it does not suite the hypothesis does not impress.
  2. 2010 - 2011: Earth's most extreme weather since 1816?
    Norman @165, there where about 326 in North America including the Caribbean in 2010. Of those, about 60 occurred outside the US, and 4 where geophysical, leaving approximately 260 weather related disasters in the continental United States. But for the sake of argument, let's pin that as the US figure. According to your source, there are an estimated 2,000 to 3,000 supercells in the US annually. Taking the higher figure, that means that supercells have around an 8% chance of causing a disaster. From your source, there where around 2,100 category 5 plus Earthquakes would wide in 2010. Of the 960 natural disasters in 2010, 9% or 86 where geophysical. Assuming them all to be earthquakes, that means about 4% where damaging. The US figures are 80 5 plus earthquakes, and 2, possibly 3 reported as disasters; and hence a 2.5 to 3.75% chance of being reported. Therefore on these rough figures, a magnitude five plus quake is less likely to be identified as a natural disaster than is a supercell. Your logic was:
    "The logic (not sure it will satisfy you). Most large earthquakes are already counted as disasters (percentage wise) whereas the vast majority of supercell storms do not become disasters but each one has the potential to. So an increase in population and property value could still explain this situation. Munich Re also points this out in there report."
    But as we have just seen, the probability of reporting as a natural disaster are the reverse of what you claim. So if we accept your logic, which I do not, we would expect an increase in population to result in more reports of geophysical disasters relative to weather related disasters, rather than the reverse. With regard to your initial comment, geophysical disasters are almost flat (no increase) over the period that weather related disasters increase threefold. Major geophysical disasters increase by about 50%, but major weather related disasters increase by about 100%, leaving a 33% increase unexplained by reporting issues.
  3. Eric the Red at 00:32 AM on 1 July 2011
    2010 - 2011: Earth's most extreme weather since 1816?
    Tom, With the exception of the early 20th century, I think the precipitation does correlate rather well with PDO. The more negative the PDO, the higher the rainfall. http://i44.tinypic.com/2eyb1xs.png
  4. Pete Dunkelberg at 00:27 AM on 1 July 2011
    Ocean acidification: Coming soon
    I'm sure the home team cam fix the links in the top post. Even nicer, they can add links to the titles as posts are added. Of course "decreasing pH = becoming more acidic = acidification." New people may bring up the question as time goes on. Instead of deleting, how about adding "Moderator Response: decreasing pH = becoming more acidic = acidification" when needed, and deleting or editing any excessive replies?
  5. Uncertainty in Global Warming Science
    Ken Lambert - "Because TSI has no equilibrium baseline - the area under its forcing curve is uncertain so its contribution to the energy sum is unknown." You are correct in that no matter when we start considering forcing anomalies, it's going to be difficult to find a point where the climate was at equilibrium. However, we have the track record of global temperatures, and a decent record of forcing changes both natural and human. We can see when the climate is gaining or losing energy over the last few hundred years. Global temperatures have gone both down and up over that period, which immediately tells us that we've seen forcings both above and below equilibrium - that the area under the forcing curve has gone both positive and negative. Given that simple piece of information, and looking at changes in forcings, we actually have a pretty good idea of the relative magnitude of the various forcing changes that are currently affecting climate. They are currently positive, we know when they were negative, and we've measured the changes. The big uncertainties at this point are indirect aerosol effects and cloud feedback - certainly not solar input. You seem to repeatedly call for 'more information', to state 'we cannot know' - this all sounds like a call for inaction in the face of what is actually pretty solid evidence.
  6. It's the sun
    JoeRG I don't know if you are aware of this, but there are several issues with your comment. First is that natural variability means that on a short time scale (5-10 years) 'climate' models can only give an approximation of the 'weather', where on 20-30 years they do an excellent job of looking at trends. It's not a miss unless the observations go outside the envelope of model predictions, the orange and blue bands representing the multiple-run envelope.. Therefore the fit with anthropogenic forcings is quite good. Second, given recent higher grade measurements of forcings, the post 1950's fit is accordingly better in the models. Third, 'global dimming' shows up in both model and measurement data as change to a downward trend around 1940. I think your statement regarding that is unfounded. Finally, as to models - they are an important tool for teasing out the contributions and effects of different forcings, as well as a good check on our understanding of the physics involved. Based on our understanding of the physics of forcings, the measured changes in solar activity, volcanic activity, etc., natural forcings should have cooled the climate considerably since mid-century. That did not happen - anthropogenic forcings made the difference, hence current warming. So again, the statistically significant (obvious to the point of a boot to the head) break between natural forcings and climate response became visible mid-20th century. I suggest you read the Models are unreliable thread if you have such concerns about the use of models as tools.
  7. Uncertainty in Global Warming Science
    KR #79 "That said, your repeated claim that 'integral of TSI explains all' (paraphrasing) is indeed a PRATT" I have not claimed that 'integral of TSI explains all'. What I have said is that integral of ALL the AR4 forcings over time (they all should have a time history and a projection forward) added to the same integral of the climate responses over time will give the total energy added to the earth system. Volcanic negative forcing also adds to this sum (the area under the spikes). In other words we are summing the net forcing imbalance over time to get the total energy added to the system. Because TSI has no equilibrium baseline - the area under its forcing curve is uncertain so its contribution to the energy sum is unknown. Temperature and phase change of the masses engaged will respond to this energy total somewhere in the system.
  8. 2010 - 2011: Earth's most extreme weather since 1816?
    Norman @167, the SH data does not have the same dry period wet period pattern you are commenting on, but it has an even stronger trend (3.31 mm/decade) than does the NH (1.53 mm/decade). Interestingly, the SH lacks both the mid century temperature peak and the (slightly out of phase) mid century precipitation peak which are both so prominent features of the NH and global data. Further, you are inventing an unexplained cycle from the whole cloth as the pattern does not correlate well with any of the great oceanic oscillators (including such dubious ones as the AMO, which I just checked. Further, even if it was a cycle, you would not be able to check phase only trends without at least two positive and two full negative phases to check. Finally, as noted above, the SH trend is much stronger than the NH trend. The NH trend dominates the global trend, never-the-less because this is a land only index, and there is so much more land in the NH. This suggests that if it was a land/ocean index (unfortunately not possible due to lack of data) it would show a much stronger trend dominated by the SH, and hence lacking the features you are trying to build a case on.
  9. 2010 - 2011: Earth's most extreme weather since 1816?
    Eric the Red @164, I had noticed that, and even checked out a number of possible causes including: Insolation (which peaked in 1950) ENSO PDO NAO Sulfates (global dimming) Correlation between SST and Land Temp In each case there was either no obvious connection, or in some such as insolation there was good reasons to rule it out as a cause. The most important feature to note is that the NH and SH peaks do not correlate. In particular, there are many high precipitation years around 1920 in the SH as in the NH, but they are not the same years, and there is no equivalent to the 1950's peak in the NH in the SH (which rules out insolation as a cause). The best correlation with an oceanic oscillator is with the PDO (1950's peak), but the rise in precipitation in the 1980s starts far to early and far to strong for the PDO to be the cause. Consequently I would say the precipitation is tracking temperature, but imperfectly because of the noisy nature of the data.
  10. Eric (skeptic) at 22:28 PM on 30 June 2011
    Throwing Down The Gauntlet
    When my old electric water heater blew, I replaced it with another because it was my most energy efficient option. After I installed it I turned it down to the lowest possible setting (meaning the shower is just hot enough in winter when turned all the way to hot). But I also added 100 feet of PEX on the cold input so I can add some sort of preheater. Right now my preheating comes from a south facing outside wall painted black, but I can do better (for one thing PEX doesn't transfer heat well). I have more black-painted wall for passive solar heating (covered in plastic with a PV-powered fan to draw warm air in). I have enough PV electric and batteries for 100% solar computing and some emergency refrigeration. Bottom line is my electric bill is $30/month but up to $50 last summer when it was so blazing hot (60 days at 90F or above). In winter about $35 since I use a bit more hot water. My propane use for heating and cooking is minimal since I used wood for most heat and winter cooking. The electric bill includes all water (lots of new trees to water) and pumped septic. What's next? I would love to experiment with hydro electric, but 30 foot floods make that challenging (no trend since 1930 http://waterdata.usgs.gov/nwis/monthly?referred_module=sw&site_no=01631000&por_01631000_2=188914,00060,2,1930-09,2010-11&format=html_table&date_format=YYYY-MM-DD). I would gladly give up land to dammed waters (I would get better kayaking and fishing) and a right-of-way. Other ideas: passive solar greenhouse, more passive solar heating and cooling.
  11. 2010 - 2011: Earth's most extreme weather since 1816?
    Tom Curtis @ 160 My post at 158 was a poor one and I should not have made it. I just want to comment on the trend line in your second graph. I might have a different view here. I see a dry period followed by a wet period which may be linked to global warming or it could be some longer term cycle that produces dryer and wetter periods. A trend line from the dry cycle to the wet cycle indeed shows an increase. What if the trend line is drawn just in the wet cycle and just for the dry cycle considering the possibility that these are some cycles of unknown mechanism but cycles never-the-less. I would doubt you could show an upward trend of the wet cycle in graph two of your post. That was my observation.
  12. Eric the Red at 22:22 PM on 30 June 2011
    Websites for Watching the Arctic Sea Ice Melt
    Sphaerica, I said give me time, that is not a cop out by any stretch of the imagination. Here is my response: Using CRU data, the 10-yr centered moving average increased 0.59C from a low in 1967 to a high in 2002. Therefore, if temperatures decreased by a similar magnitude over a similar time period, then I would say it was all natural, -0.6C by 2037. Using the same data, the calculated climate sensitivity over the 35 years is 2.8. Therefore, based on an expected CO2 increase of 17.5% by 2037, the temperature should rise another 0.65C. Then I would say it is all CO2. Obviously any changes of similar magnitude in shorter timeframes would yield a similar result. The other number to watch is a temperature decrease of 0.2C by 2028. That is the average of the last two cooling periods, and would indicate that both natural and CO2 forces are impacting temperatures. The resulting climate sensitivity would be ~1. I think that I have set some fairly solid bounds for you. Your middle analogy is woefully inaccurate, as you imply it results from indecision and apathy, rather than scientific inquiry. In reality, there is only one answer, and it lies somewhere between the left and right shoulder of the road.
  13. 2010 - 2011: Earth's most extreme weather since 1816?
    DB @ 163 The writers of the article do believe it is a valid proxy for determining wet and dry cycles for the larger region of the Northern Great Plains. "Devils Lake is of glacial origins, and the fact that it is a closed lake has allowed meaningful paleoclimatological studies using proxy information to estimate elevation changes several thousand years before the present time. These reconstructions (Bluemle, 1991; Murphy et al., 1997).reveal numerous cycles between high and low water levels that have been interpreted to indicate wet and dry cycles over the northern Great Plains (Fig. 1)" There is no global climate there are regional climates. To determine if these regions are changing you can only examine one region at a time to look for a signal of increasing extremes. I did post a local point on snowfall for Omaha Nebraska earlier and was rebuked for this. After this I am trying to find historical information on various regions and it seems Devil's lake is considered a regional proxy.
    Response:

    [DB] The author's of that study use statistical analysis tools to arrive at their conclusions (which apply to the Devil's Lake area only).  In your prosecution of your narrative you do not use any statistical analysis of your own, relying instead on the sturdy Eyecrometer and "common sense".  On a science-based forum such as this, you are not living up to the standards of believability.

  14. 2010 - 2011: Earth's most extreme weather since 1816?
    Tom Curtis @ 154 If you go back to your post on 55 with the two types of disaster graphs (disasters and major disasters). If you look at the number difference between geophysical and weather related at the start of each graph. The number of weather related disasters is so many times higher. I have not worked it out yet but I am wondering if the starting higher number would increase the probability of a disaster from weather over geophysical when the population rate goes up at about the same rate as the disaster chart. Wheras the increasing population is not changing the lower number as much, the geophysical disaster frequency is going up on both graphs, just more slowly. Also with large geophysical disasters, being a much smaller yearly number have less probablility of disaster. But with severe storms just in the US there are about 2000 to 3000 supercell thunderstorms a year. Link to number of annual supercell stroms in US. Of those 2000 storms, anyone which could become a disaster, only a few of these become listed as disasters. With Earthquakes you have a much smaller number that cause disasters (need to be close to the 6 magnitude to cause one in areas with better construction). Your short list does show this. You can also see by matching the numbers on your post at 55 with the earthquake numbers that most large earthquakes do cause a disaster somewhere. Earthquake number and magnitude. The logic (not sure it will satisfy you). Most large earthquakes are already counted as disasters (percentage wise) whereas the vast majority of supercell storms do not become disasters but each one has the potential to. So an increase in population and property value could still explain this situation. Munich Re also points this out in there report.
  15. Climate half-truths turn out to be whole lies
    Kevin C, that's a fantastic piece of information. It will make it much easier to rebut assertions of global temp records being wrong due to incomplete global coverage.
  16. Eric the Red at 21:18 PM on 30 June 2011
    2010 - 2011: Earth's most extreme weather since 1816?
    Tom, Have you compared your rainfall anomaly graph with the GISS temperature anomaly posted in #158? The rainfall follows temperature, but with an ~15 year lag.
    Response:

    [DB] What physics-based explanation do you propose for that?  Otherwise it's another case of "I see cycles".

  17. 2010 - 2011: Earth's most extreme weather since 1816?
    Camburn @ 152 I did read through your Devil's lake article. It does show a similar concept of what I have been trying to point out in my numerous posts. Histroically the climate does not appear to be getting worse. There are large variations in rain amounts (drought and flood cycle) going back several centuries. When looking at the long history of any given area I have examined, I cannot conclude from the evidence that climate patterns are becoming more extreme or that flood/drought cycles are more intense, more frequent, or longer in duration.
    Response:

    [DB] The inescapable conclusion is that one cannot draw regional or global inferences based on single point references.  So the premise of your comment and your concept is based on a fallacious understanding of time series analysis.

  18. 2010 - 2011: Earth's most extreme weather since 1816?
    DB in 158 Thanks for the correction. I did reread Jeff Masters point on that and it is not that warmer air woould cause more overall rainfall (as you pointed out) but more extermes. Heavier rain in some areas and stronger droughts in others. You are completely correct. This is a very intelligent website and the posters expect and demand a higher level of reasoned responses. Too many mistakes and misunderstandings is too sloppy. I am trying to demonstrate points of histrorical weather patterns but a failure to keep it error free will work to make my posts seem sophmoric and not worry of consideration.
  19. The Climate Show 15: Michael Ashley and the ineducable Carter
    To be honest, I rarely watch the show - I download the podcast onto my iPod and listen to it while doing chores. My interview is on at the 45 minute mark and hurtles by for only 13 minutes (over that time, my daughter walks past in the background, our dog ambles by and you can see the back of Wendy's head the whole time).
  20. Ocean acidification: Coming soon
    That list of punning headlines would make any sub-editor proud. Does 'always take the weathering' make any sense outside of Oz and NZ? Looking forward to the series.
  21. Throwing Down The Gauntlet
    "Cool", yup, that's definitely what they're thinking Adelady, no doubt about it. Well, actually it might be bemusement, it's difficult to tell sometimes. I'm sticking with 'electric motorbike' though, electric bike means electric bicycle to me. And plenty of bragging rights when it comes to mpg conversations.
  22. Throwing Down The Gauntlet
    Oh, & I've also gone with a Green Power scheme recently. I only use around 5-6kw-h of electricity per day, so its only costing me an extra 1c/kw-h for 100% Green Energy. That's a *bargain* in my opinion-especially once the carbon tax kicks in ;-)!!!
  23. Throwing Down The Gauntlet
    I went with a Continuous Flow Gas Hot Water system myself. Cost a few hundred dollars more than an electric hot water storage system but, in the 5 years since I installed it, its paid for itself several times over. Plus its generating a fraction of the CO2 emissions that my old water heater used to generate, because its much, much more efficient!
  24. Throwing Down The Gauntlet
    David, I think the personal/ domestic action is worthwhile. Mainly because of the general perception that running the government is much the same as running a household or a business. (I think this is a bit misguided, but nevertheless it's there.) If people see that it's 'normal', 'economical' or even 'cool' to take these actions, the stage is set for more general economy wide action. ('Cool' refers to the opinion of school students about a teacher happily coasting straight past school buses held up in traffic - on an electric bike, not a motorbike. It actually looks more like a Vespa scooter.) When lots of people in your street have solar PV, you're not becoming a 'hippie' or a 'greenie' if you instal it too. And it's easy to get bragging rights in your retirement village - my mum always checks the readings on her system before she goes anywhere.
  25. The Planetary Greenhouse Engine Revisited
    @ Patrick I downloaded the free software FreeFem++ at http://www.freefem.org/ff++/ which solve the PDE systems and I used it. I used a domain 90x120. The abscissas between X15 and X75 represent an entire Earth’s meridian circumference, that’s, X15 is the equator at midday, X30 the North Pole, X45 the equator at midnight, X60 the South Pole, X75 again the equator at midday. The abscissas 0-X15 and X75-X90 have been used only to obtain a perfect symmetry of the range X15-X75 with respect to X45. The ordinates represent the Earth’s atmosphere layer high 120 km above the surface. The assumed surface temperatures change sinusoidally along the meridian being 200K at poles and at equator 290K at midnight, 320K at midday. Using FreeFem++ I have solved the two-dimensional problem in the steady state using the follow system: ∇•u = 0 //continuity u •∇u + gk + Cp∇T – νΔu = 0 // momentum u •∇(CpT + gz) – λΔT = 0 // total energy without KE imposing a) T = 270 K at 120 km (within the thermosphere) and at 50 km (top of the stratosphere) b) T = temperature of equilibrium due to the emission 6e-8*T^4 for the thermal sinks of the tropopause at 10 km and the mesopause one at 90 km and plotting a) the temperatures ”(temperature)” b) the vertical velocities ”(vertical velocities)” c) the vectors velocity ”([u,v])” d) the lapse rates at X15 (equator at midday) ”(X15-equator at midday)” , at X22.5 , mid latitude at midday, ”(X22.5-mid latitude at midday)” , at X30, poles, ”(X30-poles)” , at X37.5, mid latitude at midnight, ”(X37.5-mid latitude at midnight)” , at X45, equator at midnight, ”(X45-equator at midnight)” I have to make amends for my mistake. The mesosphere lapse rate is not able to activate the convection. I have reduced the ordinates to 10 km and plotted also the horizontal and vertical components of the velocities which are quantities with sign so it is possible to understand the sense of the eddies thermally induced. ”(velocities X90)” I have plotted some lapse rates for different latitudes. At the equator the concavity of the lapse rate is positive showing that the energy of the lower atmosphere is increasing both in daytime and nighttime; for the mid latitudes the lapse rates day/night are linear; at the poles the concavity of the lapse rate is negative because the falling air is losing its energy.” (lapse rates of temperatures)” The results of this very simple simulation confirm what was well known: - we need different temperatures on the surface to activate circulation induced by convection - the turbulence is present almost exclusively within the lowest region of the tropopause - if the Earth is not rotating and then without the Coriolis forces, the global circulation occurs according to a simplified one-cell way between the equator and the poles, as we can see, e.g., at http://www.physicalgeography.net/fundamentals/7p.html or at many other sites of physical geography on the web. The most important result is that it is enough to add two radiating layers at the top of both the troposphere and the mesosphere and the behavior of the entire atmosphere seems satisfactorily (even if grossly) explained. May be, the physics is more and more simpler than we tend to depict it.
  26. Throwing Down The Gauntlet
    Given perseus's point above I'll tell you about my new electric motorbike: It costs not significantly more than an equivalent (125cc) petrol driven bike, £3000 new, and has similar performance. Top speed 60mph. Range 40 miles, and possibly up to 70, which is more than adequate for my commute to work and back each day. Cost of charging less than 1p per mile and the batteries should last 2000 charging cycles, or about 4 to 5 years of regular use, before they need replacing (current price about £800). Even with the current energy mix this gives emissions reductions compared to a petrol bike over its lifetime - and if you're replacing a car then the savings, both financial and environmental, are massive. This is a realistic solution that's available now. I enocurage you all to participate in it.
  27. The Climate Show 15: Michael Ashley and the ineducable Carter
    Hey, that's a good 15 minutes shorter than the previous episode, so the efforts at brevity are having some effect! barry, it's well worth watching the whole lot. I like to have it open on my second screen while doing other more menial tasks on the first [cough World of Warcraft cough]...
  28. Throwing Down The Gauntlet
    I think the economic argument for some sorts of action is quite strong (thus the comment about the denier with the rooftop PV). A few years back, our (electric resistance) hot water system failed. We paid a premium of ~$1,000 or so to go solar. Since then, our electricity bill has been about $100/quarter less. In another few years, the savings will have completely paid for the hot water system - total cost, not just the 'solar premium'. Given the prospects for ever-rising electricity prices, I think a rooftop PV array may be in our near future as well. I'd love to get one big enough to offset our entire daily use, but not sure the budget will stretch that far. Perseus, I like your analogy - it fits in well with the government motivation. If 50% of people with riverfront properties sandbag, then the government will probably step in and do the rest. You're certainly not going to ever get 100% community buy-in, waiting for that means the whole enterprise is doomed because of the cranky denier on the corner who claims the river has flooded before, it's entirely natural, we shouldn't do anything about it...
  29. Ocean acidification: Coming soon
    Also looking forward to this series! OA, all by itself, may have devastating impacts on human activity - here's a quote from an FAO briefing paper[pdf] for the COP15 conference: Fish (including shellfish) provides essential nutrition for 3 billion people and at least 50% of animal protein and minerals to 400 million people in the poorest countries. Over 500 millon people in developing countries depend, directly or indirectly, on fisheries and aquaculture for their livelihoods. Not to mention the monetary value - the NOAA indicates that commercial fisheries in the US alone were worth $3.9 billion in 2009. FAO numbers put just the international trade in fishery produce at ~$85 billion per year.
  30. It's the sun
    @KR You cannot deny that a well tuned, means a good model can predict everything wanted. Honestly, this IPCC model linked is a bad one. The only section that has a nearly proper correlation is the time after 1963 in the upper diagram (anthropogenics included). The other part, 1900 until 1963, does not fit at all. This is a mess, because this is the section to which the natural forcings have to be attuned. Neither in the upper nor in the lower diagram there are any signs of fitting the lower peak around 1910 or the higher peak in the 40th. So the predicted temperature curve is much too flat. As well, the effect of global dimming, widely accepted in science, is missing (the natural forces would have caused higher temperatures, countered by this effect). This is a clear sign of underestimated natural forcings in this model (both curves are almost identical in this time, so the anthropogenic forcings are negligible). One that claims to have a sceptic look at science must have recognized this - and, if I am right, most posters here claim it. Regrettably I have to conclude that it is not as you suggest that there would be an excellent correlation. Perhaps some kind of excellence in the part that is claimed to be important, but a mess in the offcut. Generally, models, even those accepted by the IPCC, do not always match the reality. You can of course use the models to get your conclusions, but how reliable can models be if the tuning sections don't fit at all?
  31. 2010 - 2011: Earth's most extreme weather since 1816?
    Further to Tom's point - a proper evaluation of an hypothesis is compare observation to actual model prediction not just what you think the model predicts. The models for regional effects of weather as the globe warms are not that robust but do clearly delineate areas which will get wetter and which will get dryer. The worrying thing about the Min et al paper was that there was more extreme precipitation events than models than their models predicted.
  32. The Climate Show 15: Michael Ashley and the ineducable Carter
    Yikes - it's an hour+ long. Not all of us have spare bandwidth/time to check it out. Can you do a quick round-up of the segment, or at least give the time code? Cheers, barry.
  33. Lessons from Past Climate Predictions: Don Easterbrook
    stefaan: Yes, you can add more and more cycles, sub-cycles, and epi-cycles until your simulation provides quite an accurate reproduction of past behaviour. Such models almost invariably fail the prediction test - which I believe was one of the key reasons for the downfall of the geocentric model of the solar system - as time went by, more and more sub-cycles were needed to account for the variance between model and reality, until the whole house of cards collapsed, to be replaced by the heliocentric model which was described by a few (relatively) simple equations, and which allows fairly accurate prediction centuries into the future. I think the term 'house of cards' is accurate in that example, as it was all based on, and completely relied on, one fundamental assumption, that the Earth was the centre of the universe. Observation showed that fundamental assumption was incorrect, and additional complexities were added in to the model (with no basis in physical science whatsoever) in order to account for that error. In the climate science field, however, there are multiple foundations (e.g. CO2 absorption spectra, black body radiation, conservation of energy) which are so thoroughly tested by experiment and observation that it would be very improbable for any of them to be overturned at this point in time. Tamino has a good post covering another 'skeptic' prediction that turned out to be not-so-good - this time from the 2009 NIPCC report regarding arctic sea ice. The last graph is a cracker - especially when you consider most of that data was available at the time the NIPCC report was written!
  34. 2010 - 2011: Earth's most extreme weather since 1816?
    Norman @158, your conclusion that warmer air will hold more water, and hence there will be fewer droughts is to simplistic. As a first order effect, it is in fact true that warm air can hold more water; and all else being equal, this will lead to greater precipitation. Indeed, that is just what we see globally (over land). As can be seen below, the expected daily rainfall over the globe is increasing with increasing temperatures. Based on the GRCM3 model, the expected increase is about 0.06 mm per day over course of the 20th century, and as much as five times that increase over the course of the twenty first: A 0.06 mm/day increase translates to an annual increase of 22 mm over the period 1900 to 2010, or about 2 mm per decade. That does not sound like a lot, but it is an increase in the mean global anomaly, ie, the average of the increase at all recording stations. In other words, your typical city is expected to be receiving 242 mm more rain per annum now than they where in 1900. According to Australia's Bureau of Meteorology, the trend over that period has been 2.08 mm/decade, or a mean increase of 243 mm. As a hindcast, that retrodiction was not bad. But that is just the simple stuff. In fact, the change in precipitation is not expected to be, and has not been evenly distributed in space: Some areas are expected to receive less rainfall, and consequently other areas must receive more. The natural consequence of that is that some regions are now more prone to droughts, and some more prone to floods. And one crucial point you neglected is that, if air is dry, its increased capacity to carry water just means it sucks more moisture out of the environment than it used to. That means just looking at changes in precipitation understates changes in aridity in some areas.
  35. Throwing Down The Gauntlet
    What is surely more important is that others learn by your example and the behaviour spreads. There is little to be gained in being an isolated example and making oneself feel better. Surely the community as a whole needs to be encouraged (or made) to participate. Otherwise it becomes the mentality of sandbagging your stretch of the river whilst your neighbour does nothing. It only works if everyone does it.
  36. Stephen Baines at 15:02 PM on 30 June 2011
    Climate's changed before
    That's really interesting kiwipoet. I think there are some important observations here that I have observed myself, albeit in a less obvious way. I wonder if you should post this in another thread where it might be more relavent - maybe the consensus image thread or another concerning communication of climate science. Any advice moderators?
    Response:

    [DB] Several come to mind, chief of which is probably this one:

    Infographic: 97 out of 100 climate experts think humans are causing global warming

  37. Lessons from Past Climate Predictions: Don Easterbrook
    Albatross: Well, yes. Check out this paper from his home page: http://myweb.wwu.edu/dbunny/research/global/CO2_atmospheric-carbon-dioxide.pdf
  38. 2010 - 2011: Earth's most extreme weather since 1816?
    Tom Curtis # 149 You chop too much off my concept and then use it as an agrument against my point... I continued my line about the proxy link of Munich Re. "The best posted so far is the Munich Re disaster trend. And this is an indirect proxy with too many other varialble to create a conclusive argument of the overall thesis." On the paper you reference, what did you think I was trying to show? My point of adding that paper was the larger point. Weather extremes happen all the time. The article of this thread is concerned that 2010 is so unusual and is proof that Global warming is now drastically changing weather patterns. I do not happen to share this view and post long term historical records of various locations and ask for evidence that shows a drastic or unusual nature in our current weather or climate patterns. So far I have looked at droughts. I looked at droughts in Texas, North America, Australia, the Pacific Coast. In the data I pull up I cannot see any increasing droughts in intensity, duration or frequency. I have mentioned flooding. I have found China has floods at least every other year. A proxy with too many variable that can effect it is not the best type. Some proxies are very direct. The expansion of a liquid based upon its temperature. What we are directly measuring is expansion. The expansion translates well to a temperature of the liquid. There are few other variables, besides temperature, that expand the fluid so it works well. Munich Re even mentions the many possible variables when linking disaster events to extreme weather events. It is the last page of the Munich Re report you linked to. I am not against proxies but data using them may only give you an approximation. If many variables effect a proxy then it probably would not be used.
  39. 2010 - 2011: Earth's most extreme weather since 1816?
    skywatcher @ 148 Sometimes I am not clear enough in the point I am making and I apologize for that. I was talking about the wet years cycle and it level. The wet cycles from 1950 to the present do not show any significant upward trend that I can see. You are correct during the cooler years the Global precipitation was mostly dry except a few wet years. I am thinking of connections buy may not present them well. I am not a professional presenter and I think my fingers move faster than my brain. If this was a formal paper I was writing in college, I would be more careful with my wording and thought process. I have been assured if I make a mistake in one of my posts then some interested member will point them out, I will then attempt to correct the error the best I can. Here is the connection I was getting at with the wet cycle trends on the Jeff Masters global precipitation chart. GISS global temp anomaly. You can see the temp was going down from the 1940's to the 1970's. Then it begins its rapid rise for the next 40 years. The precipitation graph does not show this increase. I am saying I can't see a similar upward trend in the precipitation graph that would prove the expected result of global warming prediction. Warmer air holds more water and this will lead to increased precipitation.
    Response:

    [DB] "Warmer air holds more water and this will lead to increased precipitation."

    What source do you have for that declaration?  As written, the logic does not parse.  As warmer air does indeed hold more water, the evidence shows that desertification and soil aridity increases overall, while precipitation events may become more severe, with greater potential for runoff and erosion.

    To have an expectation that temperature increases will then show similar upward trends is an unsupported fallacy.

    You are faring poorly in your argumentation.

  40. 2010 - 2011: Earth's most extreme weather since 1816?
    Camburn @153, if that is supposed to be a rebuke to this thread, it is ill placed. Jeff Masters does not mention tornadoes in his post. Nor has anyone here, to my knowledge, argued that there has been a statistically significant increase in the number of severe tornadoes. I and others have argued that there has been a significant increase in severe weather events in general, and that that is related to global warming, but to suggest that we should not discuss extreme weather in general is nonsense.
  41. David Horton at 13:55 PM on 30 June 2011
    Throwing Down The Gauntlet
    That is fine, but the trouble is that personal action (and I have taken actions along the lines you suggest) is nowhere near enough - only a fraction of the response needed.
  42. 2010 - 2011: Earth's most extreme weather since 1816?
    Tom Curtis @ 150 I did not know I had any credibility with you in the first place but thanks for pointing out my error. I did mean North America and for some reason put Northern Hemisphere. I checked again and I did have it correct on my original link.
  43. 2010 - 2011: Earth's most extreme weather since 1816?
    Tom Curtis @ 146 Thank you for the links to the Amazon and past droughts. You are a better cyberman than myself. Most my searches for any type of record on Amazon droughts pulled up page after page of the 2010 drought with no history.
  44. Lessons from Past Climate Predictions: Don Easterbrook
    Hi Dana, This may have been addressed, but going by Easterbrook's "predictions" it is not clear to em what he thinks climate sensitivity to doubling CO2 is. From what I can gather they suggest that sensitivity is very close to zero, in which case that would be ludicrous.
  45. 2010 - 2011: Earth's most extreme weather since 1816?
    Norman @94 (By special request) Norman is arguing against my contention (@88) that:
    "You think there is an important distinction only because you have in your mind that an Earthquake is a big thing hitting a large region. Of course, the damaging region of most earthquakes is in fact small, but you typically think of the big newsworthy quakes. In contrast your idea of a weather related disaster is just a single thunderstorm or twister. In fact, for statistical purposes it is a weather front, or a tornado outbreak; so while a big earthquake is pretty much guaranteed to damage nearby cities, a large weather related disaster is very likely to hit multiple states, or even countries."
    (Emphasis added) Against this contention he supplies the following evidence:
    "The quake just before 4:37 a.m. was centered six miles from West Salem, Ill., and 45 miles from Evansville, Ind. It was felt in such distant cities as Milwaukee, Des Moines, Iowa, and Atlanta, nearly 400 miles to the southeast. "It shook our house where it woke me up," said David Behm of Philo, 10 miles south of Champaign. "Windows were rattling, and you could hear it. The house was shaking inches. For people in central Illinois, this is a big deal. It's not like California." In West Salem itself, a chimney on one house fell and there were reports of cracks in walls. "We're very thankful we had no one injured," said Harvey Fenton, the town's police and fire chief. He was at first unsure what to make of the sudden rumbling when it woke him up. "A major shaking is the best way I can describe it," said Fenton, 58. Fifteen miles to the southeast, in Mount Carmel, a woman was trapped in her home by a collapsed porch but was quickly freed and wasn't hurt, said police dispatcher Mickie Smith. A century-old apartment building there, a former schoolhouse, was evacuated because of loose and falling bricks."
    (emphasis added) As the point of contention is the damaging radius of small earthquakes, evidence that a small earthquake has a damaging radius of around 10 miles (six miles from West Salem to the epicentre in approximately the directionof Evansville, and hence Mount Carmel, which was 15 miles from West Salem). I assume Norman has focussed on the fact that the earthquake was felt up to 400 miles away. However, what is at issue is not detection, but whether the event would have been recorded as a natural disaster, and for that, the relevant issue is the radius of damage, not of detection. Norman also presents evidence that magnitude 7 quakes can have damaging radii of up to 100 miles. Again, I do not see how this does anything but support my claim that "a big earthquake is pretty much guaranteed to damage nearby cities", and nor is it relevant to my claim that "a large weather related disaster is very likely to hit multiple states, or even countries". To put this into context, there are seven earthquakes listed by wikipedia as occurring in the US in 2010. They were: The Eureka Earth Quake (6.5), 463 buildings damaged, $43 million in losses; The Illinois earthquake (3.8) no damage or injuries; The Pico Rivera earthquake Not worth more than a stub, so no futher information; The Baja California Earthquake (more details later); The Borrego Springs earthquake (5.4) apparently no injuries or damage; The Potomac-Shenandoah earthquake , again only worth a stub; and The Indiana Earthquake (3.8) no injuries or damage. The important thing to note is that of these earthquakes, only two would count as natural disasters according to the criteria of Neumayer and Barthel, 2011, and only one, the Baja California earthquake, would count as a major natural disaster by their criteria. As it happens, the Baja Earthquake is listed as number 17 on Munich Re's list of 50 major natural disasters in 2010. They list it as causing, 2 fatalities, overall losses of $US 1.15 billion, and describe as follows:
    "Mw 7.2. 6,000 homes damaged. Water and sewage systems damaged. Telecommunication, electricity cut off. Injured: >230, evacuated/displaced: 25,000"
    Five other natural disasters in the US make the 2010 list of major natural disasters: 15) Severe storms and floods in New York and New Jersey, causing 11 fatalities, $US 1.7 billion in damage, and "Thousands of homes, businesses, cars damaged/destroyed. Losses to airport facilities and infrastructur[e]"; 22) Severe storms, tornadoes, and floods in Tennessee causing 32 fatalities, $US 2.7 billion in damages, and ">70 tornadoes. Thousands of homes and cars damaged. Water supply affected. Crops destroyed, livestock killed. Losses to infrastructure."; 26) Severe storms, tornadoes, and flash floods in "USA esp CO" (Connecticut?) causing 1 fatality, $US 0.85 billion in damages, and "Buildings, cars damaged. Losses to infrastructure and agriculture."; 33) Severe storms and tornadoes in "USA esp MT, MN", causing 4 fatalities, $US 0.83 billion and "Buildings, cars damaged. Losses to infrastructure and agriculture."; and 42) Wildfires in " USA: esp. CO" causing no fatalities, $US 0.31 billion in damage, and "170 homes, mobile homes, numerous cars destroyed, thousands of buildings damaged." (Number 50 on the list is also from the US, but does not meet the Neumeyer and Barthel's criteria for a "major disaster".) Bear in mind that the annual rate of "major disasters" have doubled over the last thirty years. Norman's contention that weather related natural hazards are not increasing is only plausible if detection rates of major natural disasters have risen by close to 100% or more over that period. If they have only risen by 50%, then there is still a substantial increase in events over that period. Looking at the list of major weather related disasters above, clearly that claim is not reasonable.
    Response:

    [DB] Fixed tags.

  46. 2010 - 2011: Earth's most extreme weather since 1816?
    I can only recommend everyone read response number 6 in the following thread. The author of said response is a scientist at NOAA. Bill Patzert
    Response:

    [DB] "The author of said response is a scientist at NOAA."

    Umm, no.  If it is indeed the same Bill Patzert as this one, then he is a scientist at JPL.

  47. Humanracesurvival at 12:48 PM on 30 June 2011
    Throwing Down The Gauntlet
    I like the blunt way this is going... Bottom line, shut down the denial machine now and do not let the MSM get away with underreporting the story of the century.
  48. 2010 - 2011: Earth's most extreme weather since 1816?
    Devils Lake is not far from the Missouri River Basin and experiencing very simliar long term precipitation trends. This study shows long term Devils Lake basin hydrology. Long Term Hydro study of Devils Lake
  49. 2010 - 2011: Earth's most extreme weather since 1816?
    Norman @145, your counter-argument against Father Theo is specious. The tornado peak in 1974 was a consequence of the very strong 1974 La Nina, while the 2011 peak (expected to be almost as large, and possibly larger) is also correlated with a very strong La Nina. Therefore attributing the large 1974 peak to "chaos" is not justified and your counter-argument fails. The annual run off for the Missouri does not show any correlation to ENSO discernible by eye. However, it does show a distinct rising trend, with 9 out of 12 MAF 34.3 events occurring in the last 40 years of a 110 year record, and the highest three occurring in the latter period in nice sequential order. This does not prove a causal relationship between global warming and high run off. However, there is a proven relationship between global warming and higher specific humidity, so the maths here isn't that hard.
  50. 2010 - 2011: Earth's most extreme weather since 1816?
    Norman @147, it would help your credibility no end if you would at least start drawing a distinction between North America and the Northern Hemisphere.

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