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Berényi Péter at 13:23 PM on 5 March 2010Visual depictions of Sea Level Rise
I can believe relative sea level changes measured by satellites, more or less. However, absolute rates are highly dubious. Earth's moment of inertia is 8x10^37 kgm^2. There is a continuous loss of rotational angular momentum due to tidal breaking (angular momentum lost goes into orbital angular momentum of Moon, Earth-Moon distance is measured to increase by 38 mm/year). It is supposed to slow down Earth's rotation, i.e. increase LoD (Length of Day) by 2.3 msec/century. On the other hand, historic record of solar eclipses for the last 2700 years indicate a 1.7 msec/century inrease in LoD. The difference is due to glacial rebound. Land formerly covered by ice sheets rises (Canada, Scandinavia), mantle material moves to the North, closer to axis to support it, moment of inertia decreases. A -0.6 msec/century change in LoD implies a 7x10^-9 relative decrease in moment of inertia per century (-5.6x10^29 kgm^2 in absolute numbers). A sea level rise of 3.3 mm/year increase measured by satellites increases Earth's moment of inertia. The mass of a 3.3x10^-3 m thick spherical shell of radius 6.37x10^6 m and having density 10^3 kg/m^3 is 1.7x10^15 kg. Moment of inertia for spherical shell is 2/3*M*R^2, i.e. 4.55x10^28 kg/m^2. In fact about 70% of Earth is covered by oceans, so actual increase in moment of inertia due to sea level rise is more like 3x10^28 kg/m^2/year. It is only an order-of-magnitude calculation, so latitudal distribution of ocean basins is considered uniform. It implies a 3.3 msec/century increase in LoD. As the secular increase is 1.7 msec/century, it would mean a 5 msec/century recent rate. Nothing like that is seen.We have data for the last three centuries (hail to astronomy).
Earth's moment of inertia varies wildly, but there is not much trend in it. The 1.7 msec/century secular trend perhaps, nothing else. Sea level rise is undetectable. It can mean two things. Sea level is either not rising, at least not on a rate compatible with satellite data or haphazard changes in shape & internal mass distribution of Earth just mask it. The two things may even be connected. Satellite measurements show large regional differences in sea level change. It may be just the underlying mantle. The coordinate system used by satellites is not rigid (in fact rigid rotating coordinate system can not even exist). It is calibrated (and re-calibrated because of orbital drift) to a selected set of "fixed" points on Earth. But those points are not really fixed (relative to what?), they are just fixed to the surface. The question is far from being settled, slope of satellite altimetry is rather arbitrary. PNAS 2002 Twentieth century sea level: An enigma Walter Munk
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Jeff Freymueller at 11:38 AM on 5 March 2010Visual depictions of Sea Level Rise
Camel: What Steve L said, plus: 6. Most of the sea level rise from the last glacial maximum was over by about 6000 years ago. So your average is meaningless, because the average rate of rise from about 6000 years ago to a few hundred years ago was very close to zero (much closer to 0 than 2-3 mm per year is). Advanced human civilzations rose AFTER sea level stabilized, which also would have stabilized shorelines, near-coastal river gradients, etc. -
Steve L at 11:24 AM on 5 March 2010Visual depictions of Sea Level Rise
Dear Camel: 1. The "or more" is important; 2 m is a lot. 2. Not much infrastructure was at risk 9000 years ago. 3. If glaciers covered Canada, sea level would be lower. 4. But that won't happen: ice-age postponed 5. It's not all about you and your house. -
gallopingcamel at 10:40 AM on 5 March 2010Visual depictions of Sea Level Rise
Satellites provide us with great precision in the measurement of sea levels. Since the start of the satellite record the rate of rise has averaged 3.2 mm/year, in good agreement with other methods. Trying to put this in perspective, the 21st century sea level rise could be 0.3 meters or more. Is that a catastrophe? During the 20th century sea levels rose by ~0.2 meters so maybe we do have a problem as the rate appears to be rising. My understanding is that sea levels have risen by 110 meters in the last 9,000 years as the planet recovered from the last Ice Age. That works out at an average of 1.2 meters per century. Thus looking at the big picture, the current rate of rise is quite low and certainly not unprecedented. I live in Florida and at the current rate of rise my home will be at sea level in 1,000 years but by then we will probably be more worried about the glaciers covering most of Canada.Response: A rise of 30 cm by 2100 is not what the peer-reviewed science is telling us. Sea levels will not continue to rise at a linear 3.2 mm per year but are accelerating, primarily due to accelerating ice loss from the Greenland and Antarctic ice sheets. Satellite gravity measurements are already observing accelerating ice loss from both ice sheets (Velicogna 2009).
Once the contribution from ice sheets are taken into account, two entirely independent analyses (one using past sea level behaviour, the other using ice sheet dynamics) find the expected sea level rise by 2100 to be between 80 cm to 2 metres (Vermeer 2009, Pfeffer 2008). . This sea level rise will be more than inconvenient to many millions of people.
You make a good point that sea level rise has changed dramatically in the past. In fact, the past tells us volumes about how sea level responds to temperature. What it tells us is that ice sheets are very sensitive to changes in temperature. Consider that our lower emission scenarios predict a warming of around 1 to 2°C. This is approximately the same as the temperatures during the last interglacial, around 125,000 years ago. At this same time, sea levels were at least 6 metres higher than current levels.
In other words, while we expect sea levels to rise 80cm to 2 metres by 2100, sea level rise won't stop there. They will continue to rise and at our current emission trajectory, we expect sea level rise of at least 6 metres. There is uncertainty over how long this will take - likely centuries. I imagine future generations will not look kindly at the late 20th Century/early 21st Century generations who ignored these multiple lines of peer-reviewed evidence for dramatic sea level rise. -
ProfMandia at 05:09 AM on 5 March 2010Every skeptic argument ever used
John, I just added three of my own links. Can we plug our own links? Climate Models & Accuracy Global Cooling? The Scientific ConsensusResponse: Definitely! In fact, for the time-pressed climate blogger, I would encourage your readers to submit your webpages to the directory. The more links we can get into the directory, the more useful a resource it will be.
Not to mention hopefully it will get more traffic and google ranking for your website. -
Berényi Péter at 05:05 AM on 5 March 2010YouTube video on the empirical evidence for man-made global warming
Two more Annals of Glaciology 5 1984 Impurities in Snow: Effects on Albedo and Snowmelt (review) Stephen G Warren PNAS Soot climate forcing via snow and ice albedos James Hansen and Larissa Nazarenko, November 4, 2003 -
BaerbelW at 04:54 AM on 5 March 2010Every skeptic argument ever used
@RSVP - your statement about Y2K is completely wrong. Not much happening wasn't due to "the simple passing of time" it had to do with folks like me working in IT preparing for January 1, 2000, doing lots of analysis and making lots of changes well in advance (think 2 to 3 years as we knew what was coming and when). Y2K wasn't a complicated issue it was the sheer number of potential problems it could cause due to a lot of old(er) code and data just working with a two- instead of a four-digit field for the year. Not too surprisingly, computer programs tend to do a lot of comparison operations like 'is "A" greater than "B" or not?' With a four-digit year that comparison works fine as "2000" is greater than "1999", but what would the result have been with a comparison between two-digit years "99" and "00" come new year 2000? Quite a lot could have gone wrong if we hadn't seen it coming and taken adequate steps to avoid it. Unfortunately, we are not taking the same precautions when it comes to mitigating climate change... -
Doug Bostrom at 04:39 AM on 5 March 2010YouTube video on the empirical evidence for man-made global warming
Berényi Péter at 19:01 PM on 4 March, 2010 Soot is indeed a player in this drama. For my part, I can't see putting all stakes on one hand. Here's a pretty rigorous model treatment with well described methods of soot's role in the climate, building on a pretty huge pile of previous inquiry: Climate response of fossil fuel and biofuel soot, accounting for soot’s feedback to snow and sea ice albedo and emissivity The paper is worth reading not only for its particular line of investigation but also because it reviews and builds on so much prior research. The conclusion is that soot plays a role but it's not dominant. -
Jeff Freymueller at 03:38 AM on 5 March 2010Visual depictions of Sea Level Rise
#24 suckfish asked, "30% thermal expansion plus 55% melting land ice equals 85%. What's the other 15%? Is there another source or is it just uncertainty in the figures?" I have not had time to read the new Cazenave paper yet, which is where the details of the answer lie, but I saw an earlier version of the work presented a couple of years ago. The answer is both. There are some other "lines" in the budget: terrestrial water storage (groundwater, lakes, rivers), and artificial reservoirs. (Changes in these are what matter for sea level rise or fall). But all of the terms of the budget are estimated independently of sea level rise, so the sum won't be 100% but if the estimates of the components are accurate the sum should agree with sea level rise given the error bounds. -
Berényi Péter at 01:27 AM on 5 March 2010Senator Inhofe's attempt to distract us from the scientific realities of global warming
#99 gallopingcamel at 03:10 AM on 3 March, 2010 "The biggest problems for the Mann et al. Hockey Stick reconstructions come not from climate scientists but from historians" Yes. Here in Europe we have chronicles going back to Medieval (and even earlier) times. According to one Hungarian chronicle, in 1216 "fruit trees blew in January". At that time there was no Gregorian calendar, so it might have occurred a week or so later, in early February. Even so, it is unheard of in recent times. -
Peter Hogarth at 01:04 AM on 5 March 2010Visual depictions of Sea Level Rise
HumanityRules at 11:10 AM on 4 March, 2010 You make a fair general point, but this is not a case of one data set correcting another which then validates the first! The tidal station data are relative (Land level-Sea Level) so to make them absolute we need land vertical offset corrections for individual samples, or vertical velocity estimation corrections for extended time series. As I briefly said, most recently this is done with nearby fixed stations which use GPS (see Woppelmann 2009 linked in post) or DORIS satellite systems that are ultimately referenced back to and integrated with other geodetic systems such as SLR (Satellite Laser Ranging) or VLBI (Very Long Baseline Interferometry). These systems are all used to generate a stable geocentric reference frame such as the International Terrestrial Reference Frame (ITRF). Once a sufficient number of vertically bench marked tidal stations are available (there are currently around 300) it is possible to “calibrate” (I’ll use this word rather than “correct”) the independent satellite altimeters (as their raw data are in a sense “orbit referenced”) to allow global coverage - which the tide stations obviously cannot give. It is also fair to suggest that the altimeters are not perfect and are subject to all sorts of error sources, however once calibrated, their output is independent of the tidal stations. Thus in turn they could then be used to estimate vertical offsets for tide station data where there is no nearby GPS station. This is not to say that all of the many sensors are not continually checked and calibrated, or that further corrections will not be made. Cross validation is certainly part of this process. However the possibility of a major error or drift having remained hidden over the past 17 years over several different satellite sensors is quoted as “unlikely”. On your point about recent acceleration, there are (of course) decadal changes in gradient throughout the historical tidal records, but the papers listed in the post give the rationale behind the reported recent increase being more significant than previous “decadal” changes. In general, it is obvious even by inspection that the shape of the long term average for the extended time series is an upwards curve, though of course this should not be substituted for careful analysis, and “long term” is relative! The “slowing down” comment was something I saw from commentators on blog sites, and was (I believe) based primarily on a couple of years worth of the then current Jason 1 data. There may well be references for this (or other previous accelerating or decelerating mini-trends in the data set), and if so I have not excluded these out of any deliberate bias, but simply because the mainstream consensus of expert opinion that I am exposed to (and have tried to communicate to a wider audience) has moved on. The best overview on the complete “system” is The Global Sea Level Observing System (GLOSS), Merrifield 2009, linked in the post. Also: OceanObs09 – Community White Paper. Observations of Sea Level Change: What have we learned and what are the remaining challenges?. Nerem 2009 https://abstracts.congrex.com/scripts/jmevent/abstracts/FCXNL-09A02a-1728088-1-OceanObs2009cwp_final.pdf -
Alexandre at 00:49 AM on 5 March 2010Visual depictions of Sea Level Rise
carrot eater #27 That's an interesting question. We can see, on the other hand, a slight spike in 1998 - which would suggest a short lag (at least on the thermal expansion side). -
carrot eater at 00:37 AM on 5 March 2010Visual depictions of Sea Level Rise
Even with lags in mind, I don't see any trace of the relative stasis in global temperatures from 1940-1970 in the sea level rise figures. Is this surprising? Is this expected? Can somebody give an explanation? -
witsendnj at 23:53 PM on 4 March 2010Tree-rings diverge from temperature after 1960
This is the most comprehensive explanation I've seen anywhere on this topic, and it's not too strongly worded. I have been looking into tree sensitivity to pollution ever since I realized that the trees are not only growing more slowly, they are actually dying at a rapidly accelerating rate. This is being reported from all over the world, not just around my farm in New Jersey. Every species of every age is in decline, as is the understory of the woods. Ozone interferes with the ability of vegetation to photosynthesize by damaging the stomata of foliage and needles. Last year, even annual plants showed the unmistakeable symptoms of exposure to toxic greenhouse gases, which is a stippling of the leaves and loss of chlorophyll, in extreme cases turning leaves into brown webs. Crop losses were disguised by the USDA and blamed on weather, but if we do not recognize this problem, famine will be the result. Photographs and links to research are posted at www.witsendnj.blogspot.com -
Berényi Péter at 23:29 PM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
Well, I have looked into the spring insolation issue. NASA has a small fortran program to calculate Insolation at Specified Location, it is called SRLOCAT.FOR and can be downloaded freely. The calendar effect turned out to be pretty large. It is even more interesting that average insolation for a specific month also depends on longitude. At the International Date Line spring can come a full day later east of it than on the other side. However, actual time zone boundaries are rather haphazard, making proper adjustment tricky. It is part of the reason monthly or seasonal averages should be handled with care. Anyway, here is average March insolation for several locations and years: 1967 (80;180) 57.75 W/m^2 (80;-180) 61.76 W/m^2 2008 (80;180) 62.02 W/m^2 (80;-180) 66.16 W/m^2 1967 (70;180) 129.17 W/m^2 (70;-180) 133.28 W/m^2 2008 (70;180) 133.57 W/m^2 (70;-180) 137.74 W/m^2 1967 (60;180) 199.09 W/m^2 (60;-180) 202.95 W/m^2 2008 (60;180) 203.25 W/m^2 (60;-180) 207.13 W/m^2 1967 (50;180) 263.59 W/m^2 (50;-180) 267.01 W/m^2 2008 (50;180) 267.31 W/m^2 (50;-180) 270.74 W/m^2 1967 (40;180) 320.35 W/m^2 (40;-180) 323.21 W/m^2 2008 (40;180) 323.50 W/m^2 (40;-180) 326.36 W/m^2 1967 (30;180) 367.53 W/m^2 (30;-180) 369.74 W/m^2 2008 (30;180) 370.00 W/m^2 (30;-180) 372.20 W/m^2 The closer the Pole, the larger the effect gets (up to than 4+ W/m^2). With retreat of Veneral Equinox, spring insolation increases, by as much as 6 W/m^2 in two hundred years (because 2000 was a leap year unlike a regular turn of century). The 8 hours retreat of equinox in 44 years is responsible for about 1 W/m^2 spurious increase in spring insolation. Also, if sum of snow covered area remains the same, just shifts from Asia to Europe, to Northern America can introduce a spurious trend. GHCN also has this time zone issue. Average longitude of GHCN stations shifted eastward by 52 degrees between 1900 and 2009. If one takes averages by latitudal bands and does not correct for longitudial shift, gets a spurious increase of some 0.5 W/m^2, in this case for autumn. -
Dikran Marsupial at 20:35 PM on 4 March 2010Visual depictions of Sea Level Rise
Just gone and checked again with Google Scholar and there are a lot more of Morner's papers from the 70s there now than last time I looked, so his Hirsch index is now rather higher than the earlier estimate, I'd say it was in the high teens. However he has very few widely cited papers from the last decade or so. -
RSVP at 20:02 PM on 4 March 2010Every skeptic argument ever used
With Y2K, everything from people losing Social Security to a nuclear holocaust were predicted. Fortunately, the simple passing of time was all that was needed to disprove the most dire predictions. For AGW, while there is no set date, there is a sense on both sides of the argument that "time will tell", and if not, it's just a matter of more time. But this is not true. Climate may be warming, but determining the source of this warming is a very different matter. -
Dikran Marsupial at 19:59 PM on 4 March 2010Visual depictions of Sea Level Rise
Bob Armstrong @ 9 I wouldn't accept Morners' criticisms without checking them out first. He has made claims against the IPCC in the past that were easily verified as being baseless. I have commented on his claims made to the Telegraph (apparently clarified in the interview) http://www.telegraph.co.uk/comment/columnists/christopherbooker/5067351/Rise-of-sea-levels-is-the-greatest-lie-ever-told.html Morner says: "One of his most shocking discoveries was why the IPCC has been able to show sea levels rising by 2.3mm a year. Until 2003, even its own satellite-based evidence showed no upward trend. But suddenly the graph tilted upwards because the IPCC's favoured experts had drawn on the finding of a single tide-gauge in Hong Kong harbour showing a 2.3mm rise. The entire global sea-level projection was then adjusted upwards by a "corrective factor" of 2.3mm, because, as the IPCC scientists admitted, they "needed to show a trend"." This isn't actually true, Morner's paper on the satelite evidence makes no mention of the specific claim regarding the single tide gauge; however he does demonstrate a complete lack of understanding of the processing of satelite altimetry data (and a fair bit of Dunning-Kruger effect). For instance he doesn't reference the papers that quite clearly explain how the adjustments have been made to the raw data from the instrument. It appears that he is basing his claims on a figure without a verifiable source that is likely to be some sort of calibration plot (and not what he thinks it is). His paper is here: http://dx.doi.org/10.1016/S0921-8181(03)00097-3 and is debunked here: http://dx.doi.org/10.1016/j.gloplacha.2006.08.002 his response is here http://dx.doi.org/10.1016/j.gloplacha.2008.03.002 note Morner STILL doesn't explain the origin of his "raw data" or explain his methodology in a way that would allow his results to be reproduced (I did try and track down his references, but they no longer exist and the closest I could find were not what he claimed them to be). Morner also claims: "When asked to act as an "expert reviewer" on the IPCC's last two reports, he was "astonished to find that not one of their 22 contributing authors on sea levels was a sea level specialist: not one"." However one of those 22 is Any Cazenave, who is a sea level specialist (there may well be others), however Booker obviously could be bothered to verify Morner's claims before publishing them. Morner elsewhere claims: "I am a sea-level specialist. There are many good sea-level people in the world, but let's put it this way: There's no one who's beaten me. I took my thesis in 1969, devoted to a large extent to the sea-level problem. From then on, I have launched most of the new theories, in the '70s, '80s, and '90s." http://www.iceagenow.com/Claim_that_sea_Level_is_rising_is_a_total_fraud.htm However his work has received very little attention, his publications give him a Hirsch index of 9 (meaning he has nine publications with more than 9 citations), which is hardly consistent with his claim to be a top sea level specialist. My Hirsch index appears to be about 12 (according to Google Scholar), and I wouldn't claim to be a leading scientist in my own field. In short, one needs to be very skeptical when reading claims of fraud ("perversion"), they are easily made, and sometimes quite easily refuted. -
libertarianromanticideal at 19:40 PM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
Hi gallopingcamel Thanks. I spent many years in the trenches of the academy in a research lab. I didn't study environmental science, but I do have first hand experience with how "science" works, from the bottom (i.e., coming up with a testable hypothesis, designing and experiment and/or model (preferably both), analysis, interpretation) to the top, (i.e., finally taking all that data and telling (one hopes) a compelling story about some aspect of how the universe works (grounded in the data), and then putting the work through the hoops, i.e., presenting the work at invited talks, conferences, etc., and then, THEN, submitting the work for publication and dealing with reviewers and editors). It's a BIG DEAL. Anyone who's consistently producing work is a GOOD scientist. The job isn't to be "right." Perhaps only God knows the "truth." It is instead to successfully, creatively, intelligently apply known methods and techniques to the data, draw conclusions grounded in the data, than then present that to the world in the hopes that, in some way, it'll, advance and inspire the thinking of others. The smearing of hard working published scientists (not that anyone in this blog is doing that) announces loud and clear "I have not a clue about how scientific knowledge is produced, and worse, I don't care, I have an agenda to pursue, an axe to grind." - Cheers, Christopher Skyi, http://libertarianromanticideal.com/ -
RSVP at 19:27 PM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
CBDunkerson Referring to the graph you posted here as relates to the question that was never answered... In the graph, there is an orange and a blue region. ( Orange on my screen.) The orange region represents extra heating of atmosphere and land combined. The blue, oceans. Whereas the heat capacity of the atmosphere and land is much lower than that of water, and whereas CO2 imparts heat directly into the atmosphere, it is hard to fathom how 20 times the amount of heat is ending up in the oceans?? In light of the graph, I should re-phrase the analogy I provided above... from "Sort of like a household budget where for years every month you basically spent every penny with zero saving, and then find out you have million dollars in the bank." to "Sort of like a household budget where for years every month you did save a penny or so, and then find out you have million dollars in the bank." "a penny or so" in any case being the orange area. The million dollar is the blue. -
Berényi Péter at 19:01 PM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
#147 doug_bostrom at 10:48 AM on 4 March, 2010 "Cherry Snow" I didn't do that, used all available data. Quadratic fit was a joke, as I've indicated (it is also a joke when applied to tide gauge data). However, the fact remains. The less sunshine the less trend you get. Even snowiest month is switching from February to January. It strongly suggests some underlying cause other than "trapping" OLR. Emissivity of snow in thermal IR is excellent. In other words it is snow white in visible, pitch black in IR. It is very effective in cooling itself provided IR can escape freely to space (i.e no cloud cover). Short wave absorptivity of fresh snow is low. But as it is getting dirty, it goes up rapidly. I does not make a difference in deep winter as sun is mainly hiding behind the globe (or clouds). But it is highly relevant in springtime with skyrocketing insolation. My bet is soot (black carbon) and plain dirt, not carbon dioxide. Due to land use change more dust is carried by winds. In fall all agricultural regions of NH called ploughland are turned into artificial wet deserts at the end of growing season. With the occasional drying up of thin upper layer of bare soil, it gets windborne and deposited elsewhere, possibly on snow. Filtering smoke for fluffy carbon particles is entirely possible, not prohibitively expensive and is already done in Europe. Wind erosion of soil can also be mitigated by dividing fields up, planting tree stripes. Both techniques have immediate local benefit, do not need international treaties and heavy government intervention to enforce. Just some public attention. Which is in short supply, should not be diverted by scaremongering. As I have said, the question can be decided by looking at regional NH winter snow cover trends (moisture vs. temperature limited areas close to perimeter). A pointer to literature? Also, it is not entirely true that spring insolation is constant. There is a Gregorian calendar effect, Veneral equinox retreating along calendar year since 1900, a 648 sec/year rate on average until year 2100 when it will be reset. There are full day jumps in leap years. In 2008 spring came more than a day earlier than in 1967. Of course the effect for autumn is the opposite. -
suckfish at 18:37 PM on 4 March 2010Visual depictions of Sea Level Rise
30% thermal expansion plus 55% melting land ice equals 85%. What's the other 15%? Is there another source or is it just uncertainty in the figures? -
gallopingcamel at 18:11 PM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
libertarianromanticideal, I never thought of myself as a sycophant but I find myself in awe of your analysis (#143). Richard Lindzen commands respect that most scientists can only dream of. Lindzen lacks the hubris and over-reaching that characterises the IPCC and its acolytes. He admits that he cannot predict whether the global temperatures will rise or fall by 2100. The IPCC on the other hand predicts with 95% confidence that global temperatures will rise by 2 degrees Celsius by 2100 and possibly as much as 7 degrees Celsius. Given that global temperatures have risen by only 0.7 degrees since 1860, the huge temperature rises predicted by the IPCC should have become noticeable by now. BTW, the Fermilab folks are a blast. I got five 500 kW precision power supplies from them as a gift! Spares too! -
libertarianromanticideal at 17:19 PM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
Hi CBDunkerson, I think you've probably characterized Dr. Lindzen here. He's certainly fodder for the global alarm contingent, but w/in the academic sphere, the man is highly respected and regarded, as much as any scientist can be w/in his field. There's simply no question about that. Fermilab is not only the institution that's invited him to give talks. These institutions do so because he's an acknowledged expert in the field, and he has something to offer. They wouldn't invite him if they didn't think that. Within the field, his hypotheses and work are not regarded as "reaching [their] last stand." He publishes, he has research grants (try to get one of those!), he trains post-docs, who need 1) an adviser who publishes at a regular rate, with their names on the paper, and who 2) gives them an opportunity to extend the work done in his lab, to present that work at conferences, and -- hopefully -- to publish. The competition for beginning (i.e., associate professor) tenure track academic positions is fierce. If the guy was on some sort of "last stand," post-docs simply would go elsewhere. That's not the case (see: http://www-eaps.mit.edu/faculty/lindzen/students.html, and http://www-eaps.mit.edu/faculty/lindzen/students2.pdf). The man is working scientist, he has a working lab which is a publishing factory -- he's doing his job and he's good at it. Period. Additionally, other experts in the field put his ideas to the test. And other researchers put their ideas, theories and hypotheses to the test, and so on. While no one completely agrees with anyone else (they may not even like them), everyone takes everyone's else work and ideas very Very VERY seriously, even if they disagree. They're paid thinkers, all of them. That's their job. If somebody stops "thinking," or they start beating a head horse, their academic research career is over, nobody invites them to talks (because they have nothing new to offer, which is the point of these professional talks), potential post-docs go elsewhere, research grant money dries up, and they stop publishing. This is definitely not Lindzen's situation. In fact, he's done something quite unusual, extremely difficult, and highly valuable. He's one of those rare researchers that is thriving in a minority camp. That's rare and it takes talent. Everyone in his field respects that. You can take that to the bank. Finally, what's the field's current stance on the issue of positive feedback mechanisms in the climate? It's not a closed issue. Copy and paste this in your browser's URL window: "forcing feedback" site:.edu This tells google to search for this keyword phase across all academic domains. You can also do a search across all government domains, e.g., "forcing feedback" site:.gov There's 100's of papers, talks, discussions. And these google searches almost certainty under-estimate the interest in the topic. If it was close to being a closed and decided issue, you would see a very different set of hits. For example, if you instead google this: either "speed of light" site:.edu you'll get 10's of thousands of hits, but ZERO are about anything seriously asking the question, "hummm . ... what effect does the 'either' have on the velocity of light?" The either theory was dis-credited by the the theory of relatively over 100 years ago. All these hits are about how the theory was dis-credited. None of this means Lindzen is "right." It does mean he's highly relevant to the discussions currently ongoing w/in the climate research community. - Cheers, Christopher Skyi, http://libertarianromanticideal.com/ -
Jeff Freymueller at 13:31 PM on 4 March 2010Visual depictions of Sea Level Rise
#16, P@J, "Will that [changes in the geoid] have a sigificant effect on what areas are impacted by sea level rise?" Yes, geoid changes do cause regional variations in sea level. These are most important close to where the ice is melting (for example, in Alaska we have estimated geoid changes as larger as 4-5 mm per year from the rapid melting). Geoid changes from possible future large-scale melting in Greenland and Antarctica would affect larger areas (because of the larger size of the ice loads). There are some additional factors that come into play when dealing with the big ice sheets -- global changes in the shape of the earth. Jerry Mitrovica had a recent paper in Science about a year ago that worked this out for West Antarctica. A summary was in Science Daily: http://www.sciencedaily.com/releases/2009/02/090205142132.htm -
Riccardo at 11:47 AM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
Berényi Péter, the linear fit is meaningless, look at the residuals (yearly averages, i'd suggest). I would not trust a second order polynomial extrapolation either unless you have good reasons to believe it will follow this law. In other words, your analysis says nothing valuable on what will happen in 2100, let alone "a huge one" or "contradict to mainstream climate theory". It's could be just a statistical trick to make things look "scientific" and i'm sure it could also work in some quarters. But you know, people here tend to believe that real science is much more serious than just this. -
HumanityRules at 11:10 AM on 4 March 2010Visual depictions of Sea Level Rise
The satelite data goes through a correction process. This correction process involves comparison to tidal gauge levels. I wonder do you have a reference for this statement in your article "Most recently, corrected tidal station data from the satellite altimeter period of 1993 to 2010 is in good agreement ". What is the basis of this correction? Has the tidal gauge data been corrected on the basis of satelite data? If both sets of data are being corrected using the other data set isn't it obvious that both will begin to agree with each other? Is the statement throughout this article that both sets of data agree with each other just a product of the correction process? Is it true that uncorrected satelite data shows no trend? Shouldn't this article focus on the data correction process as it is this that is giving us a trend? Finally why put "slowing down" in speech marks, this suggests it didn't happen when in fact from 2004-2009 it did slow down. Also for the sake of balance it would be fair to actually show a link to the reference for this work as you do with others. -
Doug Bostrom at 10:48 AM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
Berényi Péter at 10:26 AM on 4 March, 2010 You'll probably be interested in looking at Tamino's take on this: Cherry Snow He concludes there's no statistical power to conclude models have been upended by aberrant snow cover.Response: You know, what would be great here is if one of you added the argument about snow cover to the list of skeptic arguments. Then as you argue back and forth with URLs, you also add the links to the directory.
Hmm, maybe I should write some code where if someone posts a URL in a comment, it follows up with a reminder: "hey, don't forget to add this to the directory" with a link to the Add Link Form. :-) -
Berényi Péter at 10:26 AM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
Departure from Normal 2009 December 2010 January 2010 February -
Peter Hogarth at 10:10 AM on 4 March 2010Visual depictions of Sea Level Rise
From Peru at 08:41 AM on 4 March, 2010 Links for data series and images: in same order as images...The charts are my basic Excel versions updated to 2010. http://www.pol.ac.uk/psmsl/author_archive/jevrejeva_etal_1700/ http://www.pol.ac.uk/psmsl/author_archive/church_white/ http://ibis.grdl.noaa.gov/SAT/SeaLevelRise/LSA_SLR_timeseries.php http://climate.nasa.gov/blogs/index.cfm?FuseAction=ShowBlog&NewsID=239 http://ibis.grdl.noaa.gov/SAT/SeaLevelRise/LSA_SLR_movies.php http://svs.gsfc.nasa.gov/vis/a000000/a000300/a000352/index.html I think the website that the third image was from has now updated and changed, but Josh Willis still has a copy on his NASA blog site, which I've linked to. -
Berényi Péter at 10:06 AM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
Re: #144 OK. Do you have data on history of regional distribution of NH winter snow? Lack of snow cover can be due to either low moisture or high temperature. If you are right, NH winter snow cover during the last four decades increased in dry areas while decreased elsewhere by roughly the same amount. This hypothesis can be tested, it is falsifiable in principle. However, this winter has not shown this pattern. There was heavy snow in Western Europe, US, Korea & China. None of them is a desert, get plenty of rain during winter if not snow. -
KLR at 09:31 AM on 4 March 2010Every skeptic argument ever used
Fun! Here they are as an Open Office .ods spreadsheet, complete with a couple of stacked bar graphs for your edification. Feel free to add to your resources if you so desire. There are separate graphs for >100 links and <100; the latter should be broken down into 50-100 and 0-50 for legibility. Yech. Sorting out piles of manure. Off to figure out what an "Infared Iris" is. Wasn't she one of the Super Friends? You know, Superman, Batman, Aquaman, Wonder Woman... -
Si at 09:00 AM on 4 March 2010Every skeptic argument ever used
CoalGeo, yes that is clear. John talks about accelerated warming in his argument which I think is hard to justify - and not from the link of his you gave compared with your link - see the difference in the graphs? Sorry about the light relief remark - Arno's post had not been deleted when I posted - it was a very long essay on a book he had written! -
From Peru at 08:41 AM on 4 March 2010Visual depictions of Sea Level Rise
John Cook: From where are this beautiful maps and time-series shown in this post?Response: Peter Hogarth mentions that the first one comes from the NOAA Laboratory for Satellite Altimetry and the second from the NASA/Goddard Space Flight Center Scientific Visualization Studio. He has an amazing talent for tracking down sources so perhaps he'll post links... -
From Peru at 08:34 AM on 4 March 2010Visual depictions of Sea Level Rise
John Cook: This Telegraph news: "Rise of sea levels is 'the greatest lie ever told'" http://www.telegraph.co.uk/comment/columnists/christopherbooker/5067351/Rise-of-sea-levels-is-the-greatest-lie-ever-told.html merits a response (I found it following the links of the "recent claim" above). Here is claimed (full quote): "One of his most shocking discoveries was why the IPCC has been able to show sea levels rising by 2.3mm a year. Until 2003, even its own satellite-based evidence showed no upward trend. But suddenly the graph tilted upwards because the IPCC's favoured experts had drawn on the finding of a single tide-gauge in Hong Kong harbour showing a 2.3mm rise. The entire global sea-level projection was then adjusted upwards by a "corrective factor" of 2.3mm, because, as the IPCC scientists admitted, they "needed to show a trend". So TOPEX-POSEIDON, JASON 1, JASON 2 and ENVISAT are also adjusted for showing a rapid sea level rise, Mr. Nils-Axel Mörner ?! Are all this SATELLITES part of the Global Conspiracy?! Of course, Science and Deniers are both right that the IPCC need to be advised by sea level experts: it grossly UNDER-estimated sea level rise, now at 3.3 mm/yr. -
Steve L at 08:25 AM on 4 March 2010Visual depictions of Sea Level Rise
Thank you Peter. I ended up trying to calculate how much water would have to go into the atmosphere to reduce sea level by 1 mm, and I came up with 3.6x10e14 kg. This is about 3% of the amount in the atmosphere so, at least by my careless calculations, changes in water vapour would be pretty negligible compared to the >10 mm annual swings in sea level. -
skagedal at 08:22 AM on 4 March 2010Every skeptic argument ever used
Ok, so repeating some comments I made on Facebook regarding this very cool project: 1. It would be nice if there was a field for language. I'd like to keep track of articles on Swedish press, and what arguments they use, so why not use this tool - but I wouldn't want to clutter the list for non-Swedish readers. 2. I think it also could be useful with a field to classify sources in categories such as "mainstream media" and "blogs", or such. The reason is that if that you're going to cover the whole denialist blogosphere, it's going to get unwieldy, and someone might be interested in just seeing how arguments are used in regular media. But maybe it's better to wait and see how it turns out. Regards, Simon -
Peter Hogarth at 08:13 AM on 4 March 2010Visual depictions of Sea Level Rise
Steve L at 07:32 AM on 4 March, 2010 From what I have read you are correct. It can be considered as seasonal exchange of water mass between Ocean and Land storage, which would be driven more by Northern Hemisphere processes as that is where most land is. -
Philippe Chantreau at 07:53 AM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
In regions where the temperature is already low in the winter, higher temps will bring more precipitation, which will still be in the form of snow as long as the temp is below freezing. Having the average winter temps go from -6C in any location to -2C would constitue a huge increase in temp but would not yield any less snow. In fact there would likely more of it. Spring insolation has not changed with time, it certainly does not explain a trend of higher spring temperatures. The same applies to summer and autumn. In any case, your rendition of model projections and of what is said in the IPCC links you provided is not faithful to the reality of either. The model projections, once again, are in agreement with the data. As for you forcing reflexion, CO2 forcing depends on IR radiation coming from the surface, heated by solar irradiance. I would expect high albedo surfaces to convert much less solar irradiance into IR. I would also expect a surface in darkness most of the day to act somewhat the same, to a lesser extent. -
P@J at 07:51 AM on 4 March 2010Visual depictions of Sea Level Rise
It would be interesting to see how any rise in sea level was offset my shifts in the geoid resulting from mass movement. mass loss from Greenland and Antartica will surely operate faster than geostatic rebound can compensate, resulting in a subtle but measureable shift in the gravitational geoid. Will that have a sigificant effect on what areas are impacted by sea level rise? -
Steve L at 07:32 AM on 4 March 2010Visual depictions of Sea Level Rise
I have a question about Fig 2: What explains the intra-annual variation? It looks like sea level is greatest at the end of nothern hemisphere's autumn. I would guess that melt of snow and ice on land has something to do with it, or perhaps water storage and agriculture. I should google to see if water vapour varies enough to show up. But maybe somebody here can point to a good annual budget for sea level? Thanks. -
Joe at 07:30 AM on 4 March 2010It's methane
The question is not about what's in the atmosphere, but about what humans are responsible for emitting. Maybe there is a lot more CO2 in the atmosphere than methane, but what percentage of each those gases are human activities responsible for? Historically(averaging over the past 400,000 years) CO2 is around 240ppmv, and now it is around 385ppmv(60% higher). Methane is historically(over past 1,000 years) around 700ppb and now at 1700ppb(140% higher). The % for CO2 is smaller if we start from the warm period average of around 280ppmv. While the sheer volume of human released carbon dioxide and its warming affects probably are far greater than that of human released methane, humanity seems to have changed the concentration of atmospheric methane much more than that of carbon dioxide. The fact is that changes in agriculture and diet are the easiest way for an individual to lesson his or her environmental impact. Local, organic, and vegetarian diets are a simple highly effective remediation strategy. Disclosure: I am a vegetarian and so strongly biased on this particular issue, but this point cannot be ignored. sources: http://en.wikipedia.org/wiki/Carbon_dioxide_in_Earth's_atmosphere http://ecen.com/eee55/eee55e/growth_of%20methane_concentration_in_atmosphere.htm -
CoalGeologist at 07:20 AM on 4 March 2010Every skeptic argument ever used
Si, at #48: The goal of the skepticalscience.com site is to inform readers of the scientific evidence for climate change. The links you provided are not helpful in this regard (nor do they provide "light relief"), because the very real decline in Arctic sea ice cover is very difficult to discern. The following graphic shows the trend far more clearly: http://nsidc.org/images/arcticseaicenews/20100303_Figure3.png John provides several other helpful links in his post: http://www.skepticalscience.com/Arctic-sea-ice-melt-natural-or-man-made.htm The videos are particularly sobering, showing the flushing of old sea ice from the Arctic Ocean. (It's all gone, now, by the way... the old sea ice, that is.) http://www.youtube.com/watch?v=Co68_tod0dQ -
macfanpro at 07:11 AM on 4 March 2010It's satellite microwave transmissions
@dchristie64 You are forgetting two things: first, and most important, the inverse square law, as well as the difference between correlation and causation. The first problem, the inverse square law, says that the power of a electromagnetic transmission goes as you double your distance to the transmitter down by the square of it's value. This means that the results you had in the 80's were caused by radio waves orders of magnitude higher that the amount that a person gets from a satellite, due to the massive distance from the satellite. The second omission, the difference between correlation and causation, means that other factors than satellites can cause the mentioned problems, such as global warming and cancer, despite similar timing. The space age was also linked with massive technological advances, which most likely caused the mentioned problems. Sure, the first satellites showed up at around the same time, but that only means that the events are correlated, not that that satellites caused the problems. -
stevecarsonr at 07:08 AM on 4 March 2010Every skeptic argument ever used
When I read about the idea I was "skeptical" but now I see the actual page with its layout, I'm thinking "really good!". In fact, it almost needs its own home page! Well, added my first link using the form: CO2 – An Insignificant Trace Gas? I'm sure I'll be adding a few more. The challenge will be to keep a good hierarchy of arguments. That's the value of it now. Great job.Response: Thanks, Steve, I had thought your very informative pages would be a welcome resource so if you're adding them in, that's much appreciated (and I believe of much benefit to those perusing the list of arguments). -
Berényi Péter at 07:04 AM on 4 March 2010YouTube video on the empirical evidence for man-made global warming
#142 Philippe Chantreau at 04:29 AM on 4 March, 2010 Philippe, area of snow cover can only increase along the edges, not in the middle of already snow covered regions. At edge of snow temperature should be somewhere around freezing point. If winter snow coverage does not decrease, the line separating regions above and below freezing point can not move North. So NH winter snow coverage is a good (semi)global thermometer. Increased precipitation can not account for stability of winter snow cover, because if temperature is too high, one gets rain, not snow. Spring snow cover is not a very good indicator. In Northern Hemisphere insolation in spring is increasing rapidly, temperature goes up, snow melts. Spring weather is solar driven. One does not have to be an expert to know that much. In winter solar forcing is at its minimum, relative to it CO2 forcing should be more prominent. It is not. For an already cold snow covered landmass there is no other way to get even colder than either by pushing heat poleward or radiating some heat out to space for it is the coldest heat reservoir around (2.7 K). From polar regions, heat can only get out of the system, it has nowhere else to go. CO2 somehow can not trap it. -
Doug Bostrom at 05:39 AM on 4 March 2010Sea level rise is exaggerated
Argus at 05:07 AM on 4 March, 2010 Ah, you're right, different interviews. Here's what I referred to: http://www.climatechangefacts.info/ClimateChangeDocuments/NilsAxelMornerinterview.pdf In this interview, Dr. Mörner makes a lot of accusations, statements that seem reckless and would not pass muster via this site's moderation policy. Beyond that, I find the sheer amount of falsity and misconduct Dr. Mörner claims he sees to be unlikely. Dr. Mörner has a distinguished publication record in his field, yet he's sneeringly dismissive of researchers working with methods he's not accustomed to using. I'll hazard a guess about why he's so upset about this matter and sees what can only be described as a fairly vast conspiracy among other scientists. Dr. Mörner is a geologist who likes getting up to his elbows in actual material things out in the field, no bad thing. But as well, he appears to have a fundamental mistrust of numerical methods he believes are "sophisticated" in the pejorative sense of the word. He's not comfortable with remote sensing and he's not comfortable with abstractions. As an example of how Dr. Mörner's seeming lack of insight into disciplines he does not appear to understand leads him into the weeds, he summarizes research conclusions about Greenland's ice volume trend as "falsification." For me, that's where his credibility on this matter flatlines; referring to the already large and growing body of research into Greenland's ice volume condition as "falsification" is not a persuasive argument. -
Si at 05:37 AM on 4 March 2010Every skeptic argument ever used
Nice guest post from Arno - Here are some nice arctic Sea ice graphs for light relief http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg http://nsidc.org/data/seaice_index/images/daily_images/S_stddev_time Aagin, your point about the acceleration of sea ice loss is easily countered. -
Peter Hogarth at 05:09 AM on 4 March 2010Visual depictions of Sea Level Rise
D Kelly O'Day #6 The Colorado data is Topex/Jason 1. Judging from the Jason 1 website there could be temporary technical reasons for a delay in data release. Jason 1 data is also not fully updated on the NOAA site below. Anyway, there are various outlets for the altimeter data http://ibis.grdl.noaa.gov/SAT/SeaLevelRise/LSA_SLR_timeseries.php Gives a choice of all altimeters/most applied corrections, but be aware that GIA correction is not applied. I assume from your gallery of excellent charts that you can deal with netCDF data format? (most of the alternative sources use this). If not there's a free converter app for later versions of Excel (or whatever!). Daisym #12 Yes, Figure 1 is a little deceptive. The Jevrejeva 2008 data extends back to 1700 using best available (admittedly there aren't many, so uncertainty is higher) tidal stations with long records. This shows esentially "flat" long term average until around 1800, then a gently increasing rise up to current levels. I have a chart of this also if there is interest.Response: Here's the Jevrejeva data with uncertainties. For the record, Peter emailed me this graph in his first draft of his article and I edited it out in order to keep the article from getting too long. Shows what I know: -
Argus at 05:07 AM on 4 March 2010Sea level rise is exaggerated
Maybe we have heard different interviews. Anyway, I listened to a one-hour telephone (I think) interview on the site: http://itsrainmakingtime.com/2010/nilsaxelmorner/ At about 33 minutes nto the recording he talks for only a minute or so about Venice specifically, mentioning the long range of measurements available. He did not use the temporary drop as an argument. He is also generally very clear about how you must separate local changes (both going up and down), around the world's coast lines, from overall changes in the oceans. He sounds very credible and knowledgeable to me.
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