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decliner at 16:12 PM on 20 January 2010There is no consensus
Tom Dayton: Thank you. Please don't get me wrong - it's not an argument which i endorse (While a consensus doesn't prove something the existence of it doesn't prove its opposite). I just stumbled across it several times reading conservative authors (like the guy who got parodised on southpark recently), so I think it would deserve its own page. :) -
decliner at 16:00 PM on 20 January 2010It's the sun
Wow, thanks for the fast reply. It has been a while since I've seen the propagandistic "great global warming swindle" but it look like you're quite right about them hiding the decline. even tough it seems to me they at least didn't substitute it with instrumental data (i guess the red curve is the one for solar activity?) - but it's bad enough anyway. if the factor which is influencing tree ring growth is profoundly understood then it should be possible to correct for that influence, wouldn't it? Will read your page on that subject now. -
Tom Dayton at 15:58 PM on 20 January 2010There is no consensus
Decliner, the role of consensus is addressed in Naomi Oreskes's "Consensus in Science: How Do We Know We're Not Wrong?". -
HumanityRules at 15:32 PM on 20 January 2010Two attempts to blame global warming on volcanoes
This is similar to the TSI article earlier. We have multiple factors affecting global temperatures. If you try to take one of those factors such as volcanism or CO2 concentration and find a perfect relationship with global temperatures your going to fail. At certain time periods the relationship will breakdown and that can be highlighted to rubbish any connection. Do we believe that volcano activity has an overall affect on global temperature? It must do something (positive, negative or no overall affect). To highlight the lack of consensus on exactly what volcanos do is to just show how we need to improve our knowledge on this subject. Can we be concrete on our understanding of CO2 affect on global temps when we can't control for all the of factors affecting temp.Response: I wasn't highlighting the lack of consensus among scientists - I was pointing out the lack of consensus among skeptics. Skeptic arguments may contradict each other but they all have one thing in common - sow doubt so as to delay action on cutting carbon emissions.
We do have a fairly high degree of understanding of how volcanoes affect climate. This was demonstrated when Mount Pinutabo erupted. It gave climate scientists the opportunity to predict how global temperatures would respond to the injection of sulfate aerosols in the atmosphere. Hansen 2007 compares the model predictions to actual observations, shown below. The model results also confirmed the climate's net positive feedback - as temperatures cooled, water vapour in the atmosphere lessened which amplified cooling. -
decliner at 15:12 PM on 20 January 2010There is no consensus
While I agree that there is consensus I have another argument (used by several guys) for you to debunk: Science is not about consensus. -
decliner at 15:07 PM on 20 January 2010It's the sun
This solar graph has some resemblance to the tree ring proxy graph where mike's nature trick was applied to - to hide the decline. So couldn't you just use the trick as well? Then it would fit the instrumental data better. (This is not meant as a mocking, a serious reply would be appreciated.)Response: It's funny you should mention that. I'd not thought of it that way before but "hide the decline" is exactly what the Great Global Warming Swindle did when comparing sun to climate. They deliberately cut off solar levels at 1975. And as if this graphs wasn't misleading enough, they also "hide the incline" of temperature rise in 1980 - global temperatures actually go off the chart if you extend them to current temperatures:
As for "Mike's Nature trick", that situation is the case where the decline is not a decline in temperatures but a decline in tree ring growth's response to temperature. So it's entirely appropriate to not use tree rings as a proxy for temperature after 1960 when some other factor is clearly influencing tree ring growth. More on tree ring divergence... -
HumanityRules at 14:45 PM on 20 January 20102009 - 2nd hottest year on record while sun is coolest in a century
#34 response EXACTLY!! It does appear though that in your article you are dismissing solar variance because the relationship breaks down after 1975. There is nothing in this article any stronger or weaker than the "issue of mid-century cooling" by the skeptics. For that reason you should dismiss it. Riccardo Nobody suggested John was trying to fool us. But there is no reason to believe, like the rest of us mortals, that he's infallable. David Horton I have looked at the graph it starts lower and ends higher. If you put a single linear trend line through it I'm fairly sure that the slope would be positive. If you look at some of the links John has provided or google it you'll see that there is an upward trend since records began in the 1600'sResponse: Mid-century cooling is a good example of the logic used in this article. In recent decades, the sun has been cooling. Therefore, the logical conclusion is that the sun is not contributing any warming over this period.
The same logic applies to mid-century cooling. At that time, CO2 levels were rising. Therefore, the logical conclusion is that CO2 was not contributing any cooling over this period.
CO2 did not cause mid-century cooling. Other forcings must have been responsible.
The sun is not causing current global warming. Other forcings must be responsible. -
David Horton at 13:09 PM on 20 January 20102009 - 2nd hottest year on record while sun is coolest in a century
#35 "TSI going up since 1880" - have you actually looked at the graphs? -
Philippe Chantreau at 10:33 AM on 20 January 2010Two attempts to blame global warming on volcanoes
All the various factions arguing about action keep on repeating that we need more "studies" and more evidence on AGW. Seems to me they're the one wanting more work for climatologists... -
Marcus at 09:26 AM on 20 January 2010Two attempts to blame global warming on volcanoes
There is no logical flaw RSVP, for these reasons: 1. If CO2 were not the culprit, then knowing the real culprit-& how it changes the climate-could reveal a means of counteracting it. 2. By understanding the cause, we might also get insight into future effects-thus making adaptation much more successful. So you see, plenty of work for climatologists, regardless of whether CO2 is to blame. My other point is that *of course* we need to deal with overpopulation, resource depletion & general environmental degradation but (a) last time I checked, we were quite capable of "walking & chewing gum at the same time", as it were & (b) tackling many of the above problems dovetails very nicely with tackling rising CO2 emissions. e.g. reducing urban sprawl will allow more land to be maintained as forest or re-vegetated & will significantly decrease our consumption of a significant non-renewable resource-oil-both of which just happen to be outcomes which will result in REDUCED EMISSIONS OF CO2. Unfortunately, those who are most stridently opposed to the concept of AGW are also those pushing for ever greater population growth-because the ultimate outcome is the same-MORE PROFIT. If you want to understand the motives of the die-hard denialists, RSVP, you need only "follow the money". -
Riccardo at 07:14 AM on 20 January 20102009 - 2nd hottest year on record while sun is coolest in a century
The short and obvious answer to both comments is that John is not trying to fool people. -
Klaus Flemløse at 07:01 AM on 20 January 2010Two attempts to blame global warming on volcanoes
Thanks to Chris for post nr 7. From the link you gave, I have found that the Tephra Voulumen is about 100 times larger for Pinatubo than for St Helens. This explains the lack of fingerprints from St Helenesin the carbon emission. -
Doug Bostrom at 06:24 AM on 20 January 2010Two attempts to blame global warming on volcanoes
RSVP Sorry, can't help it: "If it is anthropogenic, it is because there are just too many anthropoids!" then "If we all did just stay in bed, maybe the environment would have had a chance. " Separate beds, presumably. -
Ned at 05:30 AM on 20 January 2010Two attempts to blame global warming on volcanoes
RSVP writes: There appears to be a small flaw in your reasoning #28. If global warming [is] NOT anthropogenic, it would suggest there is not a lot we can do about it. Yes, we can prepare for it, but we [can't] change it. Well, as amply documented on this very site, anthropogenic CO2 (plus CFCs, N2O, etc.) are changing the climate. So I don't see much point in arguing over a counterfactual. It's as if I said "Since much of Nevada is arid or semi-arid, water conservation is important" and you replied "Well, if it started raining a lot in Nevada, it would suggest that they didn't have to worry about water conservation." That may be a logically true statement, but it's not relevant to our world and it would be exceptionally foolish to accept that kind of reasoning as justification for stopping all water conservation efforts in the Great Basin tomorrow. -
HumanityRules at 05:04 AM on 20 January 20102009 - 2nd hottest year on record while sun is coolest in a century
" Of more significance is the long term trend " Why didn't you just put single trend line for the whole time period for both temp and TSI (I've seen it done for temp before). That would show TSI going up since 1880 and temp going up since 1880. What could we draw from that? -
HumanityRules at 04:58 AM on 20 January 20102009 - 2nd hottest year on record while sun is coolest in a century
Skeptics have long pointed out that atmospheric CO2 rise is a near perfect linear rise over the century while global temperatures have seen periods of rise, leveling and decline (as seen on your graph). If you also posted CO2 levels on the graph in figure 1 you could just as easily argue that the CO2 and global temperature graphs look unrelated in the period of 1940-1970 when temperatures where declining or steady.Response: The issue of mid-century cooling is addressed here. The basic point is there is not a single driver of climate - you need to take into account all forcings: sun, volcanoes, CO2, sulfate aerosols, etc. The same point applies to this page - sun is the not the only driver of climate and that becomes apparent when global temperatures rise during a period of cooling sun. Obviously some other forcing other than solar variations is driving the warming. -
Berényi Péter at 03:13 AM on 20 January 2010Skeptical Science now an iPhone app
Listen. If instrument quality is in doubt, the first thing a sane person does is to check the instruments themselves (as opposed to the arcane statistical properties of datasets collected by these instruments). The WMO intercomparision did exactly that. First in the lab, then there was also an extensive field test involving balloons. The important lesson learned is NOT "you get large variabilities". It is the exact nature of the variability that counts. They have found that below the 300 hPa level (for sure below 400 hPa) the humidity response of each instrument was consistently monotonic with a low enough random noise. Not necessarily linear, but monotonic. The large (up to 10%) variability was observed between different instrument types, not in the performance of a single instrument. The other issue was the different and temperaure dependent relaxation times of various types of instruments. But it was measured, documented and it is also deterministic. Now, if you have the description of instrument behaviour for each type along with time stamps, pressure and temperature data (even better to have the values for both ascent and descent), these errors are easy to eliminate. One does not even have to be a climate scientist to do that. I myself could perform the correction. I just do not know if the job was done or not. If it was done, there still remains some uncertainity. You have reffered to it as "when you actually fly a baloon there's much more than that". Actually not much more. There may be solar radiation acting on the case, water or ice can get inside due to precipitation and/or condensation, finally some random noise which is always present in any measurement. However, all these combined have much less effect than the difference between instrument classes, certainly less than the magnitude of the three decade trend. Moreover, these effects can not possibly have a definite trend over a multi decadal time scale. When I have drawn my conclusion, I assumed the trivial recalibration job I have described above is already done. If it is not, now, that's travesty. -
RSVP at 02:20 AM on 20 January 2010Two attempts to blame global warming on volcanoes
Ned. Your post 25 is one of the best, as it actually points to the way forward. If we all did just stay in bed, maybe the environment would have hald a chance. -
RSVP at 01:06 AM on 20 January 2010Two attempts to blame global warming on volcanoes
Marcus, There appears to be a small flaw in your reasoning #28. If global warming in NOT anthropogenic, it would suggest there is not a lot we can do about it. Yes, we can prepare for it, but we cant change it. One of the most irresponsible notions I have seen on this website come from those who are not willing to place the blame on overpopulation, especially when they support the theory that global warming is anthropogenic. If it is anthropogenic, it is because there are just too many anthropoids! -
Paz at 00:11 AM on 20 January 2010Two attempts to blame global warming on volcanoes
Thanks a lot, Chris. Very helpful. -
Marcus at 23:27 PM on 19 January 2010Two attempts to blame global warming on volcanoes
Another point, RSVP, is that if CO2 is not the real culprit, then this actually provides a whole new mystery for climate scientists to solve, thus giving them *loads* to do-both in determining the real culprit & trying to model the impacts of this new cause on future climate change. Indeed, a new culprit for climate change might require *more* scientists, not less, to pore over all the existing literature to try & get a handle on the real culprit. Second to this is that climate scientists existed before global warming became an issue, & would still exist if the whole thing proved to be a furphy, so your whole argument is really quite weak! -
Marcus at 23:21 PM on 19 January 2010Two attempts to blame global warming on volcanoes
By the same token, RSVP, if CO2 is the real culprit (as all the evidence seems to suggest), then reducing CO2 emissions will require significant cuts in our use of fossil fuels-which will in turn hurt the profits of the companies that mine & refine these fossil fuels. Is it any wonder, then, that a great deal of the anti-AGW bias is coming from individuals & groups with such strong links to the fossil fuel industry? -
RSVP at 22:56 PM on 19 January 2010Two attempts to blame global warming on volcanoes
Ned, Actually what you are trying to say is that if CO2 is no the real culprit, climate scientists have nothing to do. And therein lies the bias. -
Ned at 22:26 PM on 19 January 2010Two attempts to blame global warming on volcanoes
RSVP writes: Even if the current trend in global warming is actually anthropogenic, (and due solely to CO2 emissions), all it takes is one huge natural disturbance, or change on the part of nature to make anthropogenic forcing completely irrelevant (at least for a time). So? Even if you've saved up scrupulously for retirement, a large comet hitting the Earth would wreck the economy and eliminate your retirement savings. So there's no point in saving for retirement. Seriously, what is your point? As far as I can tell, every single one of your dozens of posts here consists of rather transparent attempts to justify not doing anything serious about reducing our impact on the climate system. But this one just seems ridiculous. We shouldn't bother doing anything to reduce our CO2 emissions because some mysterious catastrophe could happen suddenly and render all our work irrelevant? That logic could be used to argue against doing anything about anything. Why bother getting out of bed in the morning, when you could be hit by a streetcar on the way to work? -
Riccardo at 21:13 PM on 19 January 2010Skeptical Science now an iPhone app
Berényi Péter, the WMO intercomparison pubblication you quote is a lab test of different sensors, not field data. It assess the difficulties of the humidity readings even in controlled conditions and still you get large variabilities especially at low temperatures. When you actually fly a baloon there's much more than that. I don't want to mean that we have to discard radiosonde data, they are a piece of the puzzle. But given the large uncertainties, the small trend (a few percent) and the disagreement with satellite data, I (with Paltridge et al.) would not draw any strong conclusion, let alone claims like "Water vapor feedback in terrestrial photosphere is negative. It is as simple as that." -
RSVP at 20:26 PM on 19 January 2010Two attempts to blame global warming on volcanoes
Even if the current trend in global warming is actually anthropogenic, (and due solely to CO2 emissions), all it takes is one huge natural disturbance, or change on the part of nature to make anthropogenic forcing completely irrelevant (at least for a time). Or is this not conceivable? On the other hand, as per chris #22, even if the Earths temperature did rise 10 degrees for 500 years due to a comet, you would still have to baseline the problem from the new mean, and consider only extra forcings due to CO2 and sunlight. In other words, Paz, it doesnt matter how much heat is coming from the bottom of the sea due to hotspots and fissures.Response: Man-made warming is not due to CO2 emissions only - there are also warming contributions from ozone, methane, contrails, nitrous oxide, CFCs. But the warming from CO2 is both the strongest forcing and the fastest rising. -
Berényi Péter at 11:53 AM on 19 January 2010Skeptical Science now an iPhone app
Riccardo at 22:56 PM on 17 January, 2010: "You will easily find a lot of papers on the dry bias and possible recalibration of radiosonde data" No, not easily. I have fond something though. INSTRUMENTS AND OBSERVING METHODS REPORT No. 85 WMO RADIOSONDE HUMIDITY SENSOR INTERCOMPARISON PHASE I: Laboratory Test Central Aerological Observatory Dolgoprudny, Russian Federation June 1995 - June 1997 A. Balagurov, A. Kats, N. Krestyannikova (Russian Federation) PHASE II: Field Test NASA Wallops Flight Facility Virginia, United States 8 - 26 September 1995 F. Schmidlin (United States) WMO/TD-No. 1305 2006 http://www.wmo.int/pages/prog/www/IMOP/publications/IOM-85_RSO-RH-Phase_I-II/IOM-85_RsoHumiditySensors_Phase-I-II.pdf The analysis is thorough. And it was performed in 1995-97. More than ten years ago. I don't quite understand why was it published only in 2006. It should be enough to do the instrument recalibration job up to the 300 hPa level, verifying the long term humidity trend up there this way. I can see the NCEP/NCAR Reanalysis is going on. http://www.cgd.ucar.edu/cas/guide/Data/ncep-ncar_reanalysis.html However, I was not able to find reference to the WMO Radiosonde Humidity Sensor Intercomparision, which would be an absolute must. It may be my fault, a briefing would be welcome. So the NCEP reanalysis dataset is either uncorrected for known instrumental biases or Paltridge, Arking & Pook have revealed a gaping hole in current theory which is based on constant RH above 850 hPa. In the first case your statement "many scientists around the world are still working on this issue" lacks credibility. A job like this taking more than ten years to be done properly is flagrancy itself. Otherwise the average climate model is falsified. Water vapor feedback in terrestrial photosphere is negative. It is as simple as that. As for surfacestations.org. You know full well the quality of individual stations (or the lack of it) is not documented nearly as well in reanalysis studies as by those volunteers. One would wish for such a check on a global scale. http://www.ncdc.noaa.gov/crn/ "The vision of the USCRN program is to maintain a sustainable high-quality climate observation network that 50 years from now can with the highest degree of confidence answer the question: How has the climate of the nation changed over the past 50 years?" "Fifty years from now". Rather forty three in 2010, as the US Climate Reference Network (with some long term quality control) was started in 2003. Need say more? Surfacestations is checking USHCN (United States Historical Climatology Network), which is an entirely different beast. http://www.ncdc.noaa.gov/oa/climate/research/ushcn/ushcn.html NCDC guys are cross-checking neighboring station data, read (incomplete) station history files and do all kinds of statistical tricks, but no one goes there to have a look for the sake of good old reality check. -
chris at 09:41 AM on 19 January 2010Two attempts to blame global warming on volcanoes
re the TP Barnett et al paper in my post #19 above. The url corrupts when pasted here (perhaps John Cook can fix it!). You can find the downloadable pdf by Googling using the search term: Penetration of human-induced warming into the world's oceans. Barnett TP The link to the pdf will be high up on the list of results...Response: I've fixed the link in Comment #19. What I think happened was you copied and pasted the URL from the google search results. The problem is google abbreviate the URLs that they display in the search results (hence the /../ peppered through the URL). You need to click on the link then copy and paste the full URL from the browser's URL bar.
BTW, thanks for posting that paper. When I get around to the "heat from underwater volcanoes are causing global warming" argument, Barnett et al is a key part of the answer. -
chris at 09:18 AM on 19 January 2010Two attempts to blame global warming on volcanoes
re #12 From Peru The apparent dichotomy of the apparently quite sizeable geothermal heat flux (0.09 W/m^2) compared to the radiative forcing from CO2 (0.9 w/m^2) is resolved by noticing that the geothermal flux isn't a forcing. The geothermal flux is the background stationary level of heat flow from the interior, and since this has been proceeding for millenia and more into the deep past, the earth's ocean/surface temperatures will be near equilibrium with respect to the geothermal flux (unless it has changed massively in reecent times). So the forcing is near zero. It would be more appropriate to compare the geothermal flux (0.09 W/m^2) to the total solar flux averaged over the earth surface (1370/4 W/m^2). -
Riccardo at 09:05 AM on 19 January 2010Two attempts to blame global warming on volcanoes
a few minutes too late, and chris's answer is more detailed ;) -
Riccardo at 09:01 AM on 19 January 2010Two attempts to blame global warming on volcanoes
From Peru, on a geological time scale even land volcanoes may have a role, as probably happened in the deep past and on a much smaller scale in the last century. But it's irrelevant for recent global warming, what matters is what changes, not what is constant. One more point, as Gavin Schmidt said a while ago answering a question, underwater volcanoes would warm the deep ocean more than the surface, which is not happening. -
chris at 08:56 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Another way of addressing your question Paz, is to examine the vertical distribution of enhanced ocean heat in a warming world. The time variation of enhanced heat will be quite different if the heat penetrates the ocean from the atmosphere, compared to the notional situation of enhanced undersea volcanic activity (a notion which completely lacks evidence - one would have to postulate that undersea volcanic activity has all of a sudden increased by a truly vast amount). There's a fair amount of analysis of enhanced ocean heat distribution, and this is consistent with ocean warming as a result of heat penetration from the atmosphere. A "classic" paper is this one, downloadable from the link below (there's quite a bit of more recent studies too...): Barnett, T. P. et al. (2005) Penetration of Human-Induced Warming into the World's Oceans Science 309, 284-287 -
Tom Dayton at 08:39 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Sorry, Paz, I don't remember. Look at the comment I cross-referenced earlier, and click on the links you find there; they might have what you're looking for. Otherwise I suggest looking at the U.S. Geological Survey web site. -
Tom Dayton at 08:36 AM on 19 January 2010Two attempts to blame global warming on volcanoes
From Peru, the forcing from solar minimum and solar maximum is zero. Because the min and max cancel each other out, over every 11 years. And geological timescales are irrelevant to the past 150 years in which human-induced warming has been most pronounced. -
Tom Dayton at 08:32 AM on 19 January 2010Two attempts to blame global warming on volcanoes
From Peru, I got the data from the sources I listed in the comments I cross-referenced in my previous comment. Where I wrote "For details, see ....". You should read first, type second. -
Paz at 08:29 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Thanks Tom, very interesting. Do you know of any charts that track recent the amount of underwater volcano eruptions over the recent decades? -
From Peru at 08:28 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Tom Dayton: Remember that the difference between Solar Maximum and Solar Minimum TSI is near 1 W/m^2 .Taking into account the Spherical Surface of the Earth, this gives us a forcing of 0,25 W/m^2. Now 0,09/0,25 = 0,36 ... 36% of Solar Variability! If your data is true, it can be an important Climate Forcing on geological timescales! -
yocta at 08:26 AM on 19 January 2010Two attempts to blame global warming on volcanoes
To add to Tom Dayton's comment..although this is to do with CO2 emissions rather than heat from undersea/submarine volcanoes the US Geological survey has a comparison of CO2 emissions from volcanoes vs. human activities. ...Human activities release more than 130 times the amount of CO2 emitted by volcanoes--the equivalent of more than 8,000 additional volcanoes like Kilauea... http://volcanoes.usgs.gov/hazards/gas/index.php -
From Peru at 08:20 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Geothermal Heat emission = 0.09 watts/m^2 ? This is 10% of our measured Radiative energy imbalance of 0.9 watts/m^2! Where do you get this data? 10% seems too much! -
Tom Dayton at 08:09 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Paz, the heat coming from undersea volcanoes along with the entire rest of the crust of the Earth (0.09 watts/m^2), is tiny compared to the forcing from CO2 (2.66 watts/m^2). For details, see my comments #234 and the following #235 in the Skeptic Argument Volcanoes emit more CO2 than humans. -
From Peru at 07:48 AM on 19 January 2010Two attempts to blame global warming on volcanoes
This is a thing that continues to cause me a headache: The Early 20th Century(1900s-1940s) Warming of 0,4 ºC. It seems to me a lot strange that it peaked in the 1940s (then followed by a slight cooling of -0,1ºC until the 1970s) when both: a)Solar Activity peaked in the 1960s b)Big volcanos erupted(after near 50 years of calm) in the 1960s So, why Temperatures peaked in the 1940s and not in the 1960s? My suspect were Tropospheric, man-made AEROSOLS, but after seeing the GISS graph, TOTAL forcing still peaked in the 1950s at 0,5 W/m^2, still A DECADE(1950s) AFTER TEMPERATURES BEGAN TO COOL! What is going on? It could be: 1)Errors in temperature data or in the GISS total forcing estimation(this second is more likely as Aerosols Forcings are still considered "highly uncertain") 2)Climate Variability masking the (warming)forcing in the 1950s (for example, a series of weak El Niños and strong La Niñas) What do you think? -
Paz at 07:35 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Is there any data on underwater volcano eruptions? An argument that seems to be popping up more and more is that global warming is driven by underwater volcanoes that (1) warm the oceans, which (2) in turn warm the athmosphere. Is there any data about whether this can be ruled out? I think the appeal of this argument comes from a) that underwater are supposedly hard to track (so a large scale increase of eruptions could be going on without our knowledge) b) several recent papers arguing that part of the recent warming is driven by the oceans. It did some searching and could not find anything on this hypothesis, although I am sure it must be out there. -
yocta at 07:02 AM on 19 January 2010Why does CO2 lag temperature?
oops I meant CO2 in this case not lagging temperature :$ -
Andy Skuce at 06:42 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Klaus, you may find this article helpful: http://climate.envsci.rutgers.edu/pdf/ROG2000.pdf On page 192 there's the following statement: "While the Mount St. Helens eruption of 1980 was very explosive, it did not inject much sulfur into the stratosphere." There's also a table on the same page comparing historic eruptions and the various indices used to measure the intensity of the eruptions and their effect on climate. -
chris at 04:11 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Klaus, the site urled just below has a list of all of the major known volcanic eruptions of the Holocene (having Volcanic Explosive Index of 4 and higher). If you click on each volcano in the list it gives you detiled information about known properties. You might get some info there as to why St Helens isn't on the graph. It was a pretty major explosion, but perhaps it didn't have a large effect on very high altitude transmission of solar radiation..??? http://www.volcano.si.edu/world/largeeruptions.cfm?sortorder=desc 70n, a very quick way of assessing the Mauna Loa record is to compare it with the record of CO2 averaged over the sea surface sites. The data are continuously updated at the NOAA Mauna Loa site. The Mauna Loa record is very similar to the record of the sea surface average: http://www.esrl.noaa.gov/gmd/ccgg/trends/ -
Klaus Flemløse at 03:49 AM on 19 January 2010Two attempts to blame global warming on volcanoes
I am very facinated by the Mount St. Helens explotions in 1980. To me it was big.However is not at the graphics. Is it as mistake ? Do you have a listing of vulcanoes by size ? http://en.wikipedia.org/wiki/Mount_St._Helens -
70rn at 03:06 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Yeh? Well it's nice to have that off the list of arguments. All we have to do now is minutely scan every centimetre of the sea floor for volcanoes, (who are there in their millions apparently, pumping away in vast numbers with out changing the temperature profile or acidity of the ocean significantly, which is thoughtful) and you might even cause some ambivalence on this issue in a few heads. -
Ned at 02:51 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Thanks, 70rn. It's even simpler to point at all the other CO2 monitoring stations that have been set up elsewhere: http://gaw.kishou.go.jp/wdcgg/ Just as an example, I clicked on "Data / Quick Plot", then "Barrow" (Alaska), then "CO2 (continuous)", then chose Monthly data "File / Quick Plot", and plotted the result as a PNG. Lo and behold, a nice rising trend in CO2 from 1973 onward, with a strong seasonal cycle, too. I don't know of any volcanoes at Point Barrow, and I am unaware of any volcanoes that belch CO2 with such a nice, smooth, consistently rising trend over three decades! -
70rn at 02:01 AM on 19 January 2010Two attempts to blame global warming on volcanoes
Here's a paper discussing the detection and removal of local co2 emissions from the Mauna Loa ('mount' obviously, but get better search results when you that term) record. Basically it states that localized co2 from the vents is at a completely different concentration and not mixed with the surrounding air and as such easy to distinguish from the background. It also notes that it is variable minute by minute - were as background data is steady over hours. -
70rn at 01:39 AM on 19 January 2010Two attempts to blame global warming on volcanoes
@ Ned Yeh the Mount Loa comment is pretty hard to shake off. A point to highlight to those that make this claim is the lack of a spike in the data last time it erupted (84) and the fact that the volcanoe has been overall less active than normal over the following quarter of a century, and as such if the readings were contaminated by the site then the data should have shown a corresponding decline. I don't doubt that the current data is calibrated against other sites in the NOAA network as well as secondary observations from sources like weather balloons.
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