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citizenschallenge at 15:38 PM on 12 October 2012Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
It was funny coming across my comment. What a difference a couple years makes. I found every word interesting, or should I say compelling, this time around. We live and learn. ~ ~ ~ Incidentally, here's an interesting recent talk about the history of ocean temperature observations: 135 Years of Global Ocean Warming - UCTV's Perspectives on Ocean Science "Join Dean Roemmich, Scripps physical oceanographer and study co-author, as he describes how warm our oceans are getting, where all that heat is going, and how this knowledge will help scientists better understand the earth's climate." -
Nuccitelli et al. (2012) Show that Global Warming Continues
chriskoz - A small point of disagreement, at least in emphasis. Solar energy is the only significant heat source, as anything else (geothermal energy, waste heat from our industrial use) is 2 or 3 orders of magnitude smaller. Changes in solar energy, on the other hand, are tiny - an order of magnitude smaller than anthropogenic greenhouse forcing changes over the last 150 years. Therefore when attributing causes of global warming over that period, solar changes simply are not in the ballpark for consideration. Dale - As dana1981 pointed out, the oceans (representing ~93% of the thermal mass of the climate) have continued to warm over the period you mentioned. The atmosphere represents only ~2.3% of the climate thermal mass, and any variations in the efficiency of which the oceans absorb energy will show much larger temperature variations in the atmosphere. There certainly have been variations in radiative imbalance over the last decade - ENSO, aerosol loads, etc. - but given that ocean heat content (OHC) continues to rise, even those are fairly small change regarding ongoing climate trends. To quote Galileo, or at least something attributed to him: "Eppur si muove" - And yet it moves. Global atmospheric temperatures represent but 1/40 of the climate energy, albeit a portion we pay considerable attention to. -
chriskoz at 13:13 PM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
I further elaborate the response to Dale@24. Dale asks:What can cause the oceans to keep warming (as shown in the 2002-2008 line in the table in the article) when the accumulated heat sources decreased? Presumably, because we had the deepest solar minimum (as shown in http://data.giss.nasa.gov/gistemp/2011/) at that time.
Note that solar energy is not the only heat source. it'd variations (shown as TSI changes on the quoted page) resulted in some -0.23Wm-2 radiative forcing from 2000 on. The other heat sources (or more precisely radiative forcings): GHG, land use, albedo from aerosols, did not change much or slightly increased (CO2). As I said above, the total radiative imbalance from all sources is estimated to be 0.5Wm-2, so the drop in TSI did not result negative forcing: the earth as a whole was still gathering heat in the last decade. The strong hiatus (LaNina) esp in the end of last decade, resulted in the larger than average radiative imbalance in the last row on Table1. And that makes sense, because that table is a measure of heat imbalance. The more heat goes into ocean, the more radiative imbalance we have because the surface temperature (not the deep ocean) must rise to allow GHG to dissipate the enegry into space. You can also see from the last row of Table1, that hiatus has largest influence on planetary energy shifts than TSI variations. Again, makes sense and confirmed by others. -
skywatcher at 13:06 PM on 12 October 2012Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
dr2chase, to add to KR's points, research the Laurentide, Scandinavian and British Ice Sheets, all present at the Last Glacial Maximum, along with other hefty mid-latitude ice caps in the Alps, Patagonia and elsewhere. The extent of many of these has kept geomorphologists busy for decades (early work was 19th Century), with estimates of thickness (e.g.research on nunataks), available ice volumes have become better understood in recent decades. These can be compared to the palaeo sea level record of water volume locked up in all ice sheets, as the water has few other places to go! So we have some pretty good knowledge of the size and shape of individual large ice sheets in past times. It was the big mid-latitude sheets that were most vulnerable to rapid change under pre-Industrial forcing, but modern forcing places the Antarctic (esp. WAIS) and Greenland into the "vulnerable" category. But... It's a much more complicated question to determine how fast the sheets might melt under a given forcing, as there are issues of feedbacks, dynamical responses, surface elevation changes, moisture availability amongst many other things. You can't simply look at the "coastline", at least in part because significant ice margins were on land! That's where some modelling comes in, to give insight into key processes, constrained by the geomorphological, sea level evidence and appropriate dating of each. Events like Meltwater Pulse 1A happened, but the processes driving that rapid sea level rise are not necessarily straightforward. Something like it may not happen to Greenland or Antarctica (the glaciology may not be favourable), but as yet it can't be easily ruled out. -
citizenschallenge at 12:09 PM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Congratulations, Dana Nuccitelli, Robert Way, Rob Painting, John Cook and last but certainly not least John Church, You folks continue to impress and educate. Dana's quick reply to Dale's (@24) question was welcome since, as they say, it was "an excellent question" and I'd been chewing on it hoping you would reply. The reminder of Rob's "The Deep Ocean Warms When Global Surface Temperatures Stall" and the further links at the bottom of that post were great. Rob's "Ocean Cooling Corrected, Again" - "Ocean Cooling Corrected, Again" - "Ocean Heat Content And The Importance Of The Deep Ocean" (happened to have reread that one a couple days ago) Ari's "Deep ocean warming solves the sea level puzzle" Doug's "Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us" Are all cued up and ready for a rereading, but I wanted to stop back in again and say thanks for getting all this important information out there. Considering the steady degeneration of the contrarian-skeptic's dialogue into infantile rantings and emotionalizing (see the SkepticForum for examples) - you must be having a positive impact. Keep it up. By the way Daniel B. thanks for that link to "Global ocean currents 1994-2002" at http://www.youtube.com/watch?v=5tRiZG-yR24&NR=1 I hadn't seen that video before, beautiful and awesome ! -
Riduna at 11:45 AM on 12 October 2012Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
I largely agree with Dr Mitrovica’s analysis of the effects of ice sheet melting and gravity on sea level but it does provoke questions. I note that he leaves to the very end of his lecture, a prediction making Hansen’s prediction on sea level rise look conservative. Hansen warns that present average global temperature is only a few tenths of a degree below the Eamian maximum when sea level was 5-6 metres above existing levels. Metrovica’s analysis predicts sea level rise of 6-8 metres by 2100 making both Hansen’s prediction and my own (4 metres) look somewhat conservative. I also agree with his conclusion that both USA coasts are very likely to prove particularly vulnerable to sea level rise caused attributable to ice loss from the WAIS but my view is that GIS will also contribute to rising sea levels on the east coast of the USA and that major cities and infrastructure on and near that coast will be inundated as a result. -
Dale at 11:30 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Thanks Dana. -
dana1981 at 11:11 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Dale @24 - it's a matter of more heat being shifted to the deeper oceans during 'hiatus decades'. See this post by Rob Painting on the subject. -
Dale at 10:16 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Probably a silly question, but one I have all the same. According to GISSTemp there hasn't been much movement either way in global surface temps (basically flat since 2003). We also know that from 2005-2010 we saw the deepest solar minimum in satellite records. My question: what can cause the oceans to keep warming (as shown in the 2002-2008 line in the table in the article) when the accumulated heat sources decreased? Source: http://data.giss.nasa.gov/gistemp/2011/ -
Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
dr2chase - You might also research geological records of ice sheet extent; there is a lot of data available on extents, although the thickness of the ice sheets is still a point of discussion. -
Philippe Chantreau at 09:26 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Congrats on the publication! Good to see that the SkS team not keeps up with the science but even adds to it. -
dana1981 at 08:51 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
From Peru @21 - a pre-published version is linked in the post where it says Nuccitelli et al. (2012). -
Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
dr2chase - As I indicated, I would expect more information as isostatic and gravitational effects are disentangled with regional sea level proxies. That should include the possibility of determining mass distributions in both glacial and interglacial periods, depending on the number and certainty of those sea level proxies. I am looking forward to those papers. -
From Peru at 08:29 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Is there somewhere a pre-published version of the paper? (most physics papers are pre-published in Arxiv) -
dr2chase at 08:15 AM on 12 October 2012Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
KR@16, yes, that's the state of the ice now. But in the paleoclimate record, what was the state of the ice just before sea level started rising multiple meters per century? -
dana1981 at 08:15 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
chriskoz @19 - 0.62 is just the conversion factor between J/yr and W/m2. For the radiative imbalance see Table 1 in the paper and post. Our results are in the same ballpark as Hansen and a number of previous radiative imbalance studies. In the ballpark of 0.5 W/m2, depending on exactly what timeframe is considered. -
chriskoz at 08:09 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Dana@17, That number (Ftoa = 0.62Wm-2) coincides with the best estimate of the TOA radiative imbalance (I remember Jim Hansen said it was 0.5Wm-2). Looks like those numbers mean the same, at least to me. Can it be considered some confirmation, that TOA flux calculated from OHC changes (by large the main heat sink on the planet) and from radiative imbalance fall into the same ballpark? -
vrooomie at 07:24 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
"SkS being an outlet of the League of Evil Scientists." Wha??? Where's my sticker, then?...;) I tend to think yours, and others, opinions are correct. If (snort..."if"...) Watts resorts to that, I see it as just more rhetorical rope with which to hang himself. I do 'sense a disturbance' in the (bloggers') Force that suggests the tide is truly turning towards science. It might be wishful thinking, however... -
Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
dr2chase - See the USGS reference on this topic. Potential (m) / Location 64.80 / East Antarctic ice sheet 8.06 / West Antarctic ice sheet 0.46 / Antarctic Peninsula 6.55 / Greenland 0.45 / All other ice caps, ice fields, and valley glaciers 80.32m Total In other words, Greenland and Antarctica are the primary repositories of land ice, and the source of past multi-meter changes in sea level. I expect that Mitrovica and company will be putting out a number of papers on specific attributions based upon relative sea level change fingerprints in the near future. -
dana1981 at 05:57 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
DMCarey @15 - to convert from J to W/m2 you first get the change in energy over time (i.e. Joules per year converted to Joules per second = Watts), then divide by the surface area of the Earth to get W/m2. There's a formula in the paper (click the Nuccitelli et al. 2012 links in the above post for a free copy). Ftoa = 0.62[d(OHC)/dt] Where OHC is in Joules per year and Ftoa (top of the atmosphere flux) is in W/m2. Converting years to seconds and dividing by the Earth's surface area yields a convenient factor of 0.62. -
dr2chase at 05:19 AM on 12 October 2012Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
AndrewDoddsUk@5, Would be lovely to know what ice was available to melt when we had meters-per-century rise. That's one part of the puzzle I'm unclear on; was this large chunks of the northern ice caps running off into the ocean? (that is, would the max rate be proportional to the length of the glacier faces onto the oceans?) Did sea level rise trigger some large positive feedback? Was it just plain *melt*? (wouldn't that require an extraordinary amount of heat delivered to white ice?) -
Composer99 at 04:41 AM on 12 October 2012The Economic Damage of Climate Denial
funglestrumpet notes: The more of those ugly wind turbines we have peppering our once beautiful landscape Others have pointed that wind turbines are a fair sight more attractive than, say, coal mines, but I would suggest most of the fixtures of modern fossil-fuel civilization are also unpleasant compared to wind farms. At the city where I live (Ottawa, Ontario), our old-school shopping centres near the city centre (Rideau Centre & St Laurent centre) are hideous concrete blocks. The building where I work is a squat metal box. The main highway through town (provincial highway 417) is a long strip of pavement marring the landscape. How are wind farms any uglier than most of the modern accountrements of affluence? -
DrYew at 04:35 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
#9 MarkR - thanks, see it now... -
DMCarey at 04:01 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
I'm afraid I have to agree with Noesis; Watts will very likely be unable to find any fault in the paper itself (excellent work, it should be noted), and as such will perpetuate something along the lines of SkS being an outlet of the League of Evil Scientists. It's a pity that in the absence of a legitamite rebuttal, attacks on character are called upon instead. I am curious though, I often see heat content changes expressed in matters of W/m2, but I am not familiar with how the conversion is done save from Btu. How exactly does one convert Joules to W/m2 for instance? -
Composer99 at 03:13 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Congratulations to the SkS team! -
Bob Lacatena at 01:41 AM on 12 October 2012Shapiro et al. – a New Solar Reconstruction
Falkenherz, To add to DSL's point about your "very likely" comment... if you made that statement in good faith, believing it to be a valid and tenable position, then you need to step back and to realize how (subtly) warped your view has become as a result of propaganda. There are a hundred (thousand?) trivial little details like this one that you have probably completely and uncritically accepted without even knowing it. Any scoffing dismissal of mainstream science, dripping with venom and disdain, is quite honestly the position of a 21st century moron, someone who wants to enjoy all of the fruits of our modern civilization while living within it like a savage. Your current position is one of a stone age aborigine who believes a camera will steal his soul, and he won't believe otherwise until the tribal shaman (in the form of an un-degreed blogging ex-TV-weatherman?) assures him otherwise. It's up to you to go back and delete these twisted preconceptions from your mental image of climate science. You need to do that before you can proceed and actually understand. On the other hand, if you did not make the "very likely" statement in good faith... -
Noesis at 01:01 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Congratulations on the paper. I suspect Watts will merely ignore the paper unless forced to acknowledge it's existence, and if forced to address it, he'll dismiss it out of hand with an ad hominem and a link back to some other previous post that attacks Skeptical Science. -
vrooomie at 00:28 AM on 12 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
T'will be interesting to see how Wattsy spins this one: kinda amazed he hasn't yet, at least as of this morning (10/11/12). congrats to all for hard work, diligence, and the wherewithal to keep up this good and important work. -
DSL at 00:22 AM on 12 October 2012Shapiro et al. – a New Solar Reconstruction
Falkenherz: "to quote the infamous wording of IPCC, 'very likely'." This is the kind of comment, Falkenherz, that suggests you're not as open-minded in your approach as you've claimed. The IPCC's wording is only "infamous" among the Heartland group and its adherents. The general public rarely encounters the actual language of the IPCC (how many people outside of the online climate "debate" just up and decide to read the SREX?). It was attacked because it was an inherently soft target: there was no way for the IPCC to use language that could not be attacked. If they had used numerical values for confidence and certainty, they would have been attacked (in presentation to the general public) for trying to quantify certainty (which, to the general public, seems impossible). Had they expressed any sort of absolute certainty, they would obviously have been attacked for being unscientific (science does not deal in absolutes). What would you have them do? Or are you just satisfied to re-hash the attack, an attack that serves absolutely no purpose within the context of the current argument but does act semiotically to place you within a certain group from which you've previously attempted to divorce yourself? Further, if you really want to understand this, then you're going to have to do the math to some extent. There are free spreadsheet programs with useful functions, if you don't have Excel. There are other resources to help you as well. Science of Doom is basically an online textbook. It has taken me four years (spare time, after the babies go to bed) for me to work out the details well enough to not feel like a complete idiot when I open my mouth. -
wili at 23:52 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Yes, congrats on a great article. I'm always trying to find ways to express scientific info to a more general public. Wiki shows the energy released from the Hiroshima bomb to have been ~6 x 10^13 joules. Adding the figures for heat increase in the top 700 meters and from 700-200 meters gets me, eyeballing it, about 25 x 10^22 joules. So can I tell students and others that the amount of heat GW has added to the top ~2000 meters of ocean is roughly equivalent to 4 billion Hiroshima bombs? (And this all since ~1972!?) Please check my maths and other assumptions. Do we have updates on the OHC levels since 2008? Thanks ahead of time for any corrections/pointers...Moderator Response: [DB] Glenn shows in this post that the amount added from 1961-2011 (133 Terawatts) is equivalent to 2 Hiroshima bombs a second. Continually since 1961. -
Bob Lacatena at 23:51 PM on 11 October 2012Climate time lag
Falkenherz, The article does not "jump." It introduces a key concept, radiative imbalance, and then relates it to the problem. It is, in fact, the crux of the above post. I agree that it could be clarified, but you can't expect every blog post to qualify and explain every single detail within it. At some point you have to say "gee, radiative imbalance, I don't quite understand that, maybe I should go read up on it and then come back and re-read this article again." Or, you could invite a lengthy stream of comments, all of which explain it to you, and yet...I believe these are two totally different things...
1) Don't say "I believe." There is no "believe" in science. There is "I understand" and "I don't understand." If you say the latter, then you have more to learn. Period. Your statement is also an insult to all of the people who have posted responses to you and tried to explain it to you. Basically what you are saying is that you still don't understand and don't want to be bothered, you'd rather stick with your initial and wrong misconception. And they both are and are not two totally different things. They are different in that one (radiative imbalance) is the cause of the other (temperature change with a lag). But you can't separate them. Climate lag is not a magical fairy effect imposed by the cosmic climate-lag equation of ∂T = ΕWr⁰Ng. It is a manifestation of the fact that radiative imbalances are small compared to the heat capacity of the earth, and so that imbalance must be maintained and constant over a long period of time for a forcing to have a noticeable effect on global mean temperature. If the forcing is not large enough or not constant, there is no detectable change. If there is a detectable change, it is not linear. You need to go study radiative imbalance and understand this before you can continue. You cannot choose to skip this simply because you want to "keep it simple." That's like saying traffic signs and stop lights are too complicated. You're a new driver. It's hard enough to steer and press the gas and brake pedals, so you want to be allowed to drive around for a few weeks without paying attention to those bothersome traffic signs and laws. They just get in your way. -
Bob Lacatena at 23:34 PM on 11 October 2012Shapiro et al. – a New Solar Reconstruction
Falkenherz, First, please, you appear to have skimmed the article, or at best read it without complete comprehension. Please re-read the article several times, and when you hit something you are not absolutely sure of, go do some more research on it. But remember, the point of the article is to discuss whether or not the Shapiro reconstruction is valid, not how TSI correlates to temperature....shouldn't that just mean "faster"?
No. Why would you think that? If the NH warmed "faster" then it would get further and further out of balance with the global mean. How could that physically work?Are there any...?
What do you mean? There must be global reconstructions against which to compare the NH reconstruction, otherwise no one could state any factor at all.... 0,4 and not 0,8 Degree, as IPCC states...
Citation, please. Is this supposed IPCC statement about the northern hemisphere or the globe? To 2000, or 2007? Using 1880 as a baseline, or some other point? Was this an observed or projected value? Did you get this from an actual IPCC report, or from some blog that is itself misrepresenting a statement by the IPCC?At the same time, TSI was raising by 6 W/m2...
If you accept the Shapiro reconstruction, which is the entire point of this article. That reconstruction is an outlier with problems explicitly explained in the OP. Don't cherry pick the data that best fits your hypothesis. That's bad science.How is that possible?
(a) You're still not understanding climate lag and (b) it's probably not, which is sort of the point (that reconstruction is suspect... a 6 W/m2 increase in such a short period has all sorts of problems), and (c) as has been repeatedly explained, there are other factors in climate, and solar variation is only one (and one that in all probability does not vary greatly over time).How is that possible?
See the answer above.How is that possible?
See the answer above....maybe we can nevertheless and at least do a more general comparison of TSI and temperature levels...
Yes, we can, we have, and when we do, it seems that the correlation is very, very weak, unless you consider all of the other factors (aerosols, volcanic activity, GHGs, albedo changes) simultaneously. Which is why we have climate models, and which is why trying to sort things out with just 2 variables (TSI + GT) and one constant (climate lag) is never, ever, ever going to lead to anything of any value.... we see very rough correspondence between average GT and TSI.
Over very long time scales when using the Shapiro reconstruction, which has been called into question, and which is at odds with other solar reconstructions. So why do you uncritically cling to it? This entire post is about the issues with Shapiro, and yet you have adopted it as fact and are attempting to use it to sort out your own misconceptions of climate. Doesn't that strike you as a silly approach?Jump-conclusion: Everything seems to be "normal" at first glance?
Long answer: it shows that in the recent past the primary driver of climate, i.e. the only factor that was able to vary consistently for a long enough time to affect climate (i.e. fractionally drop or rise for hundreds of years) has been the sun. Other factors like albedo changes, volcanic activity, natrual aerosols etc. have not been strong enough or long lived enough to, over the long term in the past thousand years, greatly affect climate. But GHG are not small in their effect, and they are not short lived. They'll be in the atmosphere for hundreds to thousands of years, and their forcing dwarfs even the Shapiro reconstruction of TSI changes. So what does that tell you? Short answer: Key (wrong) words in your statement/question are "seems", "normal" and "first glance". No. You can't eyeball this stuff and get it right, there is no "normal", and first glances are always, always deceiving. You are starting from a very, very, very bad point with all of this, the assumption that the answer is as simple as that hot thing you see in the sky, and a mythical lag like the way you have to wait for the fuel pump to fill your gas tank. At the same time you are ignoring the science that describes all of the other factors, simply because it's too complicated and you want to start "easy." There is no easy. Please make some effort to actually learn the subject, all of it, and stop playing games and wasting everybody's time by taking a too simplistic approach to the subject. -
tamikenn57 at 23:32 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Congratulations! Would any of the testing be at location(s) where ocean circulations would be indicated or is deep water too shallow? -
MarkR at 20:01 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
#8 DrYew, the caption explains that it is OHC increase. I agree that the y axis label could be labelled 'heat content change' to make it clearer. -
Falkenherz at 19:38 PM on 11 October 2012Shapiro et al. – a New Solar Reconstruction
The main argument of the article is to take the difference of north globe temperature level from 1500 to 1800 (+0,15 Degree) and compares this to the same difference in TSI levels of 6 W/m2. This infers tome the question whether it is the chicken or the egg we are looking at first. Since we are right where I want to be, namely comparing the relation of long-term TSI to long-term global temperature (GT), I have some observations/questions: First, on the temperature data used here: It is stated that the Ljungqvist reconstruction exhibits larger temperature changes than the planet as a whole by a factor of approximately two. Based on my limited school knowledge about oceanic and continental climate, shouldn't that just mean "faster"? Are there any global reconstructions which show that this factor of 2 is indeed true? Also, I eyeball that the temperature difference between 1880 and 2000 is 0,4 and not 0,8 Degree, as IPCC states for the whole globe. So could it even be smaller instead of larger temperature changes, by the factor of two? Second, on comparing the curves: At 1700, temperature jumps up by 0,4 Degree, after it fell about the same about before, in the course of almost a century. Behold, the End of the Maunder Minimum (MM). At the same time, TSI was raising by 6 W/m2 (from 1360 to 1366 W/m2). This seems to be a direct feedback, without any climate lag, from TSI to GT. How is that possible? GT then stays more or less the same level for two centuries until 1900. TSI drops in between almost back to the value from the MM. How is that possible? We see another jump up of GT, roughly from 1900 to 1960, by almost the same amount as after the MM; 0,4 Degrees. TSI was raising about 4 W/m2 in that time, again, apparently no lagged response time of GT. How is that possible? My jump-conclusion: Short term relations of TSI to temperature are not possible without heavily taking into consideration all other possible forcings. Seems to make no sense otherwise. Third, not being able to correlate curves on a short-term timescale, maybe we can nevertheless and at least do a more general comparison of TSI and temperature levels: As to the medieval warm period, as well in the antique, we see very rough correspondence between average GT and TSI. High level TSI corresponds to high level temp. Temp seemed at those times roughly to be at the same level as today. And the same applies for TSI! Jump-conclusion: Everything seems to be "normal" at first glance? (Of course, an "unnormality" would be there if temp rises further in the next decades, which is, to quote the infamous wording of IPCC, "very likely".) -
Falkenherz at 19:28 PM on 11 October 2012Climate time lag
John, I would welcome that. In my opinion, some clarification would be good. Talking about global temperature being submitted to a "climate" lag is one thing, and my discussion was focusing on that. But the article jumps midway into talking about an inceased radiative imbalance. I believe these are two totally different things, and this could be clarified. Bob, my approach is rather to go from simple to more complicated. It's the natural learning process this way. gws, a lot of work, and believe me when I say I do not understand Math formulas (as I have for example no clue what a multiplier to a multiplier in brackets minus something should tell me in the end). The conclusion is of course nothing new. I was aware that most of part of the response was already before 1960; that's why we were talking about a trailing-off, and I was trying to focus on what level of difference we are actually looking at in order to determine the scale of trailing-off we should take into account. BTW, in the Saphiro article, which Sphaerica linked to, I can do a lot of observations which show that directly comparing TSI to GT on a under-100-year scale makes absolutely no sense. Sometimes you see an almost direct response, sometimes none at all. I am trying to comment that over there. My bottomline for the climate lag article here; it should probably explain how "radiative imbalance" is calculated without resorting to global temperature, as the latter seems to greatly mislead. -
DrYew at 19:19 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Could you just explain the zero level on the axis? Heat content can be neither zero or negative so I assume there's a false origin - which makes it appear as if HC has doubled since 1995. cheers jonathan -
Cornelius Breadbasket at 19:17 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
You have worked so hard on this. Very well done. -
bill4344 at 15:33 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Well done indeed, team! -
Stevo at 15:16 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
A milestone if ever there was one. Congratulations! Now keep 'em coming. -
Rob Honeycutt at 14:17 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Excellent work as always, Dana! You rock!! -
DSL at 13:37 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Hey, what's up with you people? You didn't trumpet it. You didn't wind up the press. You didn't get your minions to start babbling questionable assumptions. You let actual working climate scientists get involved. What's up with that? Congrats, all. Not surprising, so I won't add any exclamation marks. -
Albatross at 13:32 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
Congratulations to the authors! This is not going to be the first peer-reviewed paper that the SkS team produces... It is going to be interesting to see what excuses the fake skeptics are going to contrive to try and dismiss or downplay this solid refutation of DK12. It would not surprise me if at the same time, the fake skeptics fail to recognize or cede the serious problems with DK12 that undermine its entire premise.Response: [JC] "This is not going to be the first peer-reviewed paper that the SkS team produces"
Well, it is the first. Whether it's the last peer-reviewed paper that SkS produces is another matter :-) -
Daniel J. Andrews at 13:24 PM on 11 October 2012Nuccitelli et al. (2012) Show that Global Warming Continues
I saw this via twitter, and wanted to say congratulations there, but figured it would appear here where I could say it. So "Congratulations!" for getting published and for the work itself. Very nicely done indeed. Hope you all are still flying high on this. -
chriskoz at 09:33 AM on 11 October 2012Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
jyyh@12, Jerry explains that in great details starting from 25:00. Re-watch it. -
Jeffrey Davis at 07:50 AM on 11 October 2012Update from Easton Glacier: Climate Crocks on Ice
We saw a glacier in Alaska this summer that had retreated ~500 ft. In a year. -
Same Ordinary Fool at 04:33 AM on 11 October 2012Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years
Icarus @9 "He [Mitrovica] and others working on the same problem start with the equivalent of four "fingerprints" all laid down atop each other: they know how much sea levels have risen during the past century - or in some cases, several centuries - at various inhabited locations. From these observed changes, their work is to isolate the distinct impact - of the melting of the West Antarctic Ice Sheet; the Greenland Ice Sheet; other glacier systems including that in Alaska; and thermal expansion...In this way they are able to make an indirect observation of precisely how much volume and mass each ice sheet has lost." (Harvard Magazine) "Localization" effects can be determined from the difference between the video's Greenland effects map based on a uniform 1mm equivalent (of meltwater to cover the world's oceans) and another Greenland effects map with the same amount of meltwater located where the melting actually took place, based on best estimates. (Oceanography, pp32-34, Figure 4) Conceivably this might also be done with separate oceans. I bet Jerry Mitrovica could solve it, if he had enough grad students.Moderator Response: [DB] Fixed Link. -
John Hartz at 03:46 AM on 11 October 2012Climate time lag
Seems to me that the OP would benefit from an update that incorporates the some of the detailed comments being made in response to Falkenherz. -
gws at 02:47 AM on 11 October 2012Climate time lag
KR, indeed. That is why I commented that this is Falkenherz's "thought experiment". As the long time lag dominates, the picture is not too far off, but as was commented here before, the shorter air-T time lag has additional effects that make it more realistic. -
Climate time lag
A single lag time is insufficient to describe the observed climate response (as in Bob Loblaw's post, the model shouldn't be too simple). Tamino has an excellent post on this, Fake Forcing, where he examines attempts to use single lags - attempts that require ad hoc, physically unsupported tweaks to come even close; the "fake forcings". On the other hand, if you consider a two-box model, two time lags, roughly corresponding to the responses of atmosphere and oceans, you can replicate climate behavior quite well. That model (lags in Taminos example of 2 and 45 years, respectively) fits observations quite well without modifications, and has the added benefit of being based on physics. It also directly provides an estimate of climate sensitivity using purely instrumental data, of 2.4C/doubling of CO2, well within IPCC estimates. Sliding time-lines back and forth for visual matching (which also neglects the fact that the climate responds to all forcings, not just one, and that analysis should be measured by statistics, not the "eyecrometer") is equivalent to using a single-box model - that's just too simple to describe observed climate behavior.
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