Roger Pielke Sr. has raised very strong allegations against RealClimate in a recent blog post. Since they come from a scientific colleague, we consider it worthwhile responding directly.
The statement Pielke considers “misinformation” is a single sentence from a recent posting:
Some aspects of climate change are progressing faster than was expected a few years ago – such as rising sea levels, the increase of heat stored in the ocean and the shrinking Arctic sea ice.
First of all, we are surprised that Pielke levelled such strong allegations against RealClimate, since the statement above merely summarises some key findings of the Synthesis Report of the Copenhagen Climate Congress, which we discussed last month. This is a peer-reviewed document authored by 12 leading scientists and “based on the 16 plenary talks given at the Congress as well as input of over 80 chairs and co-chairs of the 58 parallel sessions held at the Congress.” If Pielke disagrees with the findings of these scientists, you’d have thought he’d take it up with them rather than aiming shrill accusations at us. But in any case let us look at the three items of alleged misinformation:
1. Sea level. The Synthesis Report shows the graph below and concludes:
Since 2007, reports comparing the IPCC projections of 1990 with observations show that some climate indicators are changing near the upper end of the range indicated by the projections or, as in the case of sea level rise (Figure 1), at even greater rates than indicated by IPCC projections.
This graph is an update of Rahmstorf et al., Science 2007, with data through to the end of 2008. (Note the comparison is with IPCC TAR projections, but since AR4 projections are within 10% of the TAR models this makes little difference.)
Pielke claims this is “NOT TRUE” (capitals and bold font are his), stating “sea level has actually flattened since 2006” and pointing to this graph. This graph shows a sea level trend over the full satellite period (starting 1993) of 3.2 +/- 0.4 mm/year and is very similar to an independent French analysis of those very same satellite data shown in the Synthesis Report (blue lines above). The best estimate of the IPCC models for the same time period is 1.9 mm/year (coloured dashed lines in the middle of the grey uncertainty range). Hence the conclusion of the Synthesis Report is entirely correct.
The “flattening of sea level since 2006” that Pielke refers to is beside the point and deceptive for several reasons (note too that Anthony Watts has extended this even further to declare that sea level from 2006 to present is actually “flat”!). First of all, trends over such a short sub-interval of a few years vary greatly due to short-term natural variations, and one could get any result one likes by cherry-picking a suitable interval (as Pielke and Lomborg both have). The absurdity of this approach is see by picking an even more recent trend, say starting in June 2007, which gives 5.3+/-2.2 mm/yr! Secondly, this short-term trend (1.6 +/- 0.9 mm/yr) is not even robust across data sets – the French analysis shown above has a trend since the beginning of 2006 of 2.9 mm/year, very similar to the long-term trend. Third, the image Pielke links to shows the data without the inverted barometer correction – the brief marked peak in late 2005, which makes the visual trend (always a poor choice of statistical methodology) almost flat since then, disappears when this effect is accounted for. This means the 2005 peak was simply due to air pressure fluctuations and has nothing to do with climatic ocean volume changes. The trend from 2006 in the data with the inverse barometer adjustment is 2.1 +/- 0.8 mm/yr.
2. Ocean heat content. The Synthesis Report states:
Current estimates indicate that ocean warming is about 50% greater than had been previously reported by the IPCC.
This is a conclusion of a revised analysis of ocean heat content data by Domingues et al., Nature 2008, and it applies to the period 1961-2003 also analysed in the IPCC report. Pielke claims this is “NOT TRUE” and counters with the claim: “There has been no statistically significant warming of the upper ocean since 2003.” But again this is not relevant to the point the Synthesis Report actually makes and again, Pielke is referring to a 5-year period which is too short to obtain statistically robust trends in the presence of short-term variability and data accuracy problems (the interannual variability for instance differs greatly between different ocean heat content data sets):
For good reasons, the Synthesis Report discusses a time span that is sufficiently long to allow meaningful comparisons. But in any case, the trend in from 2003 to 2008 in the Levitus data (the Domingues et al data does not extend past 2003), is still positive but with an uncertainty (both in the trend calculation and systematically) that makes it impossible to state whether there has been a significant change.
3. Arctic Sea Ice. The Synthesis Report states:
One of the most dramatic developments since the last IPCC Report is the rapid reduction in the area of Arctic sea ice in summer. In 2007, the minimum area covered decreased by about 2 million square kilometres as compared to previous years. In 2008, the decrease was almost as dramatic.
This decline is clearly faster than expected by models, as the following graph indicates.
Pielke’s claim that this is “NOT TRUE” is merely based on the statement that “since 2008, the anomalies have actually decreased.”
Yes, same thing again: Pielke’s argument is beside the point, since the Synthesis Report is explicitly talking about the summer sea ice minimum reached each September in the Arctic, and we don’t even know yet what its value will be for 2009. And Pielke is again referring to a time span (“since 2008”!) that is far too short to have much to do with climatic trends.
We thus have to conclude that there are no grounds whatsoever for Pielke’s wild allegations against us and implicitly the Synthesis Report authors. The final sentence of his post ironically speaks for itself:
Media and policymakers who blindly accept these claims are either naive or are deliberately slanting the science to promote their particular advocacy position.
Indeed.
Doug, I have no problem with the GHG theory or the concept of thermal expansion so no conflict between us in the basics. I do consider the rising sea levels to be indicative of warming but hardly an open and shut case especially in the face of conflicting temperature readings. Should the sea levels start to lower I would view them with the same skepticism especially should the ocean temperature measurements be going up at the time.
sidd yes, I would expect that we would be improving our attributions. I have no reason to doubt we have made improvements in the last two years. I would expect that the same could be said for direct temperature measurements also. If I was going to bet on a method that would reach an acceptable level of precision first I would put my money on direct measurements. An example of an attributing factor for sea level rise that I don’t think has received the proper amount of attention is dam construction. The world Commission on Dams state that the average age of large dams is currently 35 years. This means that the reservoirs have long since filled up and they are in a state of semi-equilibrium. Yet while they were filling up they would have reduced sea level rise. Vivien Gornitz placed the sea level rise postponed by land sequestration at 1.3 to 1.8 mm per year. If the lack of consistent dam construction and new sequestration of water canceled out half of that it could account for a significant portion of the 1990s sea level rise. Then of course there are issues of subsurface water use and subsequent release to water systems, soil dehydration during times of drought, loss of biomass from deforestation, tectonic plate movements, and soil erosion all providing their own special margins of error. Yes, I would say fixing the temperature taking methodology seems our best bet.
More likely junkies.
Well, everyone does that in Amsterdam, and they get stolen anyway. Junkies sell them at a particular bridge, but even more just get thrown into the canals for sport (A’dam has special barges with small cranes and grapples that patrol, clearing the canals of tossed-off bikes, etc).
This is unrelated to political beliefs, part being driven by the need for income to buy heroin, much of the rest driven by some sort of city-wide prank sport thinking, etc.
When I was working there some years ago, a colleague had her front wheel stolen. It was replaced by someone else’s front wheel … which had a flat tire. Swapping easier than flat-fixing.
It’s always probably wrong to associate one particular local culture with some sort of global political movement.
One estimate:
http://people.uncw.edu/culbertsonj/Ch4.pdf
… estimated that fw impoundment may be equivalent to a sea level rise of 0.5-1mm/year
Ron Broberg @ 199
Some of the difference in conclusions comes from different periods for calculating the date of rise. The site seems to use a 10 year period which is probably about the minimum for sea level change. It would be useful if the climate change community could agree on this (or another period) for reporting.
steve #251:
An essential reference:
http://www.sciencemag.org/cgi/content/abstract/1154580
No, it cannot be ignored.
#247 Ron Broberg: keep in mind that these are relative sea level rises not taking into account glacial isostatic adjustment (GIA). For the NE US sites which are in the subsiding forebulge, this could explain as much as 1 mm/yr. The Alaska paper claims negligible GIA, not sure what to think of that.
But yes, for thousands of years sea level rise has been fairly small.
Steve says: “but hardly an open and shut case especially in the face of conflicting temperature readings.”
What conflicting temperature readings?
isotopious opines: “How do you know 100 years (20cm sea level rise) is a long-term trend (in the context of planetary temp).”
Because we have a reason for there being a long term trend.
Unless you can think of a way to remove the melting ice and reverse the thermal expansion of water (maybe if it is sitting in a bay it doesn’t expand, unlike in a lab and anywhere else…).
It seems, from Roger Pielke’s most recent response that this disagreement is as much about how you parse the sentence that provoked his first ‘misinformation’ post, as it is about the data.
Some aspects of climate change are progressing faster than was expected a few years ago
He seems to interpret the sentence as meaning that the data from the last few years show the rate of change of various metrics has increased over that period, whereas the point RealClimate and the Copenhagen report were trying to communicate is that the rather longer term trends are at the high end of the IPCC expectations, indeed this is Key Message No 1 from the Congress
Recent observations show that greenhouse gas emissions and many aspects of the climate are changing near the upper boundary of the IPCC range of projections. Many key climate indicators are already moving beyond the patterns of natural variability within which contemporary society and economy have developed and thrived. These indicators include global mean surface temperature, sea-level rise, global ocean temperature, Arctic sea ice extent, ocean acidification, and extreme climatic events.
On recent sea level rise, RC point to a figure from the French analysis of 2.9 mm/year, while Pielke cites 2.5 +/-0.4 mm/yr from Cazenave et al. However for Dr Pielke this represents a ‘flattening’ because it is below the longer term rate of 3.2mm/year, so ‘Real Climate has it backwards; these climate metrics are changing less than was expected a few years ago’ while for RC the significance is that ‘The best estimate of the IPCC models for the same time period is 1.9 mm/year …. Hence the conclusion of the Synthesis Report is entirely correct.’
So both ‘sides’ are using [effectively] the same data to prove their point, which must mean that the points being made are fundamentally different!
(An interesting side issue is the use of the word ‘flattening’, Dr Pielke uses this to mean ‘decreasing in trend’, rather than ‘to become flat’ while Anthony Watts removes any such ambiguity by slapping a big pink ‘Flat’ annotation over his sea level graph, Pielke concedes that this is wrong (‘This finding is not flat’). Given the title of Pielke’s post, we’ll see if he advises Mr Watts to remove his inaccurate and misleading annotation, and if Mr Watts does so).
Pielke does not defend his assertion about the Arctic ice, maybe a short term trend too far, notwithstanding this, there clearly is no debate about the numerical values of the various metrics under discussion, the disagreement seems to boil down to a fairly unedifying and sterile semantic discussion about how these data are described and communicated to the public and policymakers.
Personally I don’t think the original post was ambigiuous, particularly when read in association with the Synthesis Report, and I don’t think it supports the interpretation about recent short term trends that Pielke places upon it, indeed one is surprised to find a scientist of his calibre apparently aligning himself with the ‘global warming has stopped’ crowd. This focus upon the short term continues in the challenge that ends his post …
1. Using the upper ocean heat data from 2004 to the present, what is the Real Climate best estimate of the accumulation of heat in Joules?
2. Using that value of heat accumulation, what is the diagnosed global average radiative imbalance over the time period? How does this compare with Jim Hansen’s value of an imbalance of 0.85 W/m2 for the end of the 1990s?
To which my response would be to query the significance of such a short period, given the large interannual, not to say decadal fluctuations in these numbers, and to ask why he apparently expects a monotonic, linear rise in OHC, especially given that this variability was explicitly noted by Hansen et al
Total ocean heat storage in that period is consistent with climate model simulations, but the models do not reproduce reported decadal fluctuations. The fluctuations may be a result of variability of ocean dynamics or, at least in part, an artifact of incomplete sampling of a dynamically variable ocean .
Surely Dr Pielke knows the distinction between weather and climate?
Phil Clarke.
re #222
steve, there are (at least!) two issues here, and it’s easy to get confused by mixing these up. Let’s focus on upper ocean heat content again:
ONE: Validity of the Copenhagen Synthesis report statement:
The Copenhagen Synthesis report presented new data on ocean upper heat content. This data shows that the long term trend in upper ocean heat content is greater than was thought to be the case a few years ago. The very recent reassessment has arisen following (amongst other things) identification of systematic warm biases in expendable bathythermographs (XBT’s) that artefactually raised the apparent upper ocean heat content for the decade around 1975-1985. The problem is described in detail in a paper published in November 2008 [***]. The corrected heat ocean content data was also used by Domingues et al (2008) as discussed in the top article of this thread. The upper ocean heat content data corrected for the XBT biases result in a larger long term upper ocean heat content than was considered to be the case a few years ago.
That’s the terms in which the Copenhagen synthesis report discussed our revised understanding of the warming trend in upper ocean heat. The long term trend due to greenhouse-induced radiative imbalance is larger than was thought to be the case a few years ago, since in earlier estimates, the early part of the record was aretfactually enhanced with a warm bias.
Note that Pielke hasn’t addressed the Copenhagen report statement on the terms in which they used this. In fact Pielke made no real argument whatsoever. His criticism consisted of an assertion “Their (sic) has been no statistically significant warming of the upper ocean since 2003.”, and a link to a previous web page containing a spurious “analysis” of yearly accumulated heat content (see my post #204 above). Neither of these address the scientific basis of the Copenhagen report statement.
TWO: Recent upper ocean heat content.
Pielke focusses on a very short recent period of upper ocean heat content. Originally in his “rebuttal” he was considering data from 2003 (see my post #204 above). In his updated pronouncements he’s shortend this to the period since 2004 (because the Levitus data shows a very large accumulated heat for 2003?). Whatever, these are extremely short periods from which one cannot draw meaningful conclusions of long term trends. In his original “rebuttal” Pielkes “argument” consisted of a link to an earlier web page in which he asserted that the “Observed best estimate” of accumulated upper ocean heat was “~ 0 Joules” for every year from 2003 to 2008, inclusive. We know (see my post #204) that this simply doesn’t accord with the recent scientific data. Pielke is misinforming his readers with his analysis (although on his more recent blog, he’s reintroduced these papers which is good).
Leaving aside Pielke, what can we say about recent upper ocean heat content? As the papers I cited above, and that of sidds (#236), indicate, the uncertainties highlighted by Willis 2008 (cited in my post #214) in which there is a short term (4-5 years) disconnect in the “sea level budget” between measured sea level rise and the independently determined mass (land ice) and steric (ocean heat) contributions, seems to be on the way to resolution. In each of the cases, the papers indicate that there has been a significant increase in ocean heat in this period. It also seems likely that the accumulated upper ocean heat content has been smaller in the last few years. It may be that is an artefact from difficulties in measuring upper ocean heat accurately (recent history of errors in both the XBT and ARGO data would lend us to be careful in making profound interpretations based on a few years of data!)…or it might be real. Of course we wouldn’t be surprised if the increase of accumulated uppoer ocean heat was small during the last couple of years in which we’ve had a strongish and extended La Nina episode, and the sun is rather reluctant to leave it’s position smack at the bottom of the solar cycle…..
[***]Wijffels SE, Willis J, Domingues CM, Barker P, White NJ, Gronell A , Ridgway K, Church JA (2008) Changing Expendable Bathythermograph Fall Rates and Their Impact on Estimates of Thermosteric Sea Level Rise J. Climate 21, 5657-5672
Abstract: A time-varying warm bias in the global XBT data archive is demonstrated to be largely due to changes in the fall rate of XBT probes likely associated with small manufacturing changes at the factory. Deep-reaching XBTs have a different fall rate history than shallow XBTs. Fall rates were fasterst in the early 1970s, reached a minimum between 1975 and 1985, reached another maximum in the late 1980s and early 1990s, and have been declining since. Field XBT/CTD intercomparisons and a pseudoprofile technique based on satellite altimetry largely confirm this time history. A global correction is presented and applied to estimates of the thermosteric component of sea level rise. The XBT fall rate minimum from 1975 to 1985 appears as a 10-yr “warm period” in the global ocean in thermosteric sea level and heat content estimates using uncorrected data. Upon correction, the thermosteric sea level curve has reduced decadal variability and a larger, steadier long-term trend.
re #259
Yup, it’s all very silly Phil! Pielke seems to be playing to the peanut gallery in his challenge to RealClimate to give an estimate of the 2004-2008 accumulated upper ocean heat content for comparison with Hansen’s modelling.
It’s particularly daft if one compares Pielke’s earlier assertion of a disconnect between Hansen’s modelled expectation of ocean heat uptake and measured heat uptake which he describes here:
http://climatesci.org/2009/02/09/update-on-a-comparison-of-upper-ocean-heat-content-changes-with-the-giss-model-predictions/
Here Pielke asserts that for “a requirement to NOT reject the IPCC claim for global warming“, various criteria of heat content should be satisfied. Thus, for example, the added upper ocean heat content must be (according to Pielke) at least 13 x 10^22 J by the end of 2008, and he asserts elsewhere that the upper oceans should have acumulated 5.88 x 10^22 J in the period end 2002 to end 2008 (if Hansens radiative imbalance GISS model projections are to be satisfied). He then proceeds to ridicule the modelling with a list of years 2003, 2004, 2005, 2006, 2007, 2008 each with “~ 0 Joules“ as their accumulated heat content!
However if we compare Pielke’s requirements with the Levitus data (see Figure in the top article to this thread), we find that (acccording to the Levitus analysis) the accumulated heat in the upper oceans is around 14.5 x 10^22 J at end 2008, and the accumulated heat in the upper oceans between end 2002 and end 2008 is close to 5.8 x 10^22 J.
So in fact the more recent analysis of accumulated upper ocean heat content is (somewhat fortuitously probably!) almost exactly what Pielke asserts it has to be as “a requirement to NOT reject the IPCC claim for global warming“!
I expect that’s why Pielke has “moved the goal posts” forward to an even shorter period (2004-2008) in his latest challenge…..
@iso:249
iso quotes Wiki:
“It should be noted that some authors propose the existence of significant short-term fluctuations in sea level such that the sea level curve might oscillate up and down about this ~1 kyr mean state. Others dispute this and argue that sea level change has been a smooth and gradual process for essentially the entire length of the Holocene..”
iso responds “Wow. Short-term = ~1 kyr mean state?”
No, iso, the short-term in this statement would be the oscillaton around the 1000 year trend – not the 1kyr trend itself.
@Vermeer:256
Good point. Probably beyond the level of the game that I’m having with isotopious. Also worth noting, analysis of tide gauge show strong regional differences. It’s not appropriate to use Chukchi by itself to try to quantify global sea level changes.
How much of sea level rise is caused by the increase in dissolved CO2? Just curious.
[Response:None. It’s way too small of an effect. -gavin]
chris #260: I don’t see anything new in this comment. I have been avoiding getting into the “what did he mean when he said that” dispute since I find the argument silly. If I want to know what someone means when they make a comment that seems obviously inaccurate compared to what I think they mean then I ask them. Who would know better what was going through their mind then the person making the statement? Perhaps he did change his “goalposts” when changing from 2003 to 2004. I see nothing wrong with a scientist changing his position to fit the data. I would be much more skeptical of a scientist that didn’t. Are there perfectly reasonable explanations why the ocean heat content may not be going up? Possibly, but the sea levels have continued to rise and so now are you arguing that even if you are wrong you are right? I don’t want to get involved in the personal animosity portion of this argument and so I will just reiterate my initial assessment: there is a conflict between sea level rise and temperature measurements. Hopefully I can leave it at that because I suspect getting any more involved in this argument will cause me to lose a very valuable resource in answering some of my questions.
My distiction between weather and climate is a matter of resolution with both respect to time and space. Both are driven by the same fundamental processes. Models, either statistical,fundamental, or a combination of both are limited by our lack of underestanding of the fundamental processes and the accuracy of the data that we try to model. A really good model should be able to predict both weather and climate changes.
Looks like the gauntlet has been dropped.
Any fuzzy kiwis here to take it up in an honest and thorough manner?
How is it possible to distinguish a sinking coral atoll from rising sea level. I mean all atolls are doomed, sooner or later they’ll all be submerged.
To Barton PL, Ron B, Hank R, GK and John M.
Thanks for your comments. We have noted them and where appropriate we will modify the site. We would welcome constructive criticism which can be sent by going to our web site and clicking on: Contact
We have also added more background on who we are and why we developed, and are still working on, the site at:
http://www.climatedata.info/FAQ/faq.html
Thanks also to Anne T Cyclone and Julius St Swithin (whose day will be celebrated on 14 July) for stopping by our site and posting comments.
Ron and Pat
Yet, our lack of understanding of fundamental processes etc doesn’t stop Fred from “proving”, in the paper linked to his sig above, that burning fossil fuels doesn’t contribute significantly to the observed increase in CO2 concentration during the industrial age. The increase is just (of course!) part of a natural cycle.
re #264
Fair enough steve. I think the arguments have been pretty much played out on this thread now. I would just say that (as I indicated in my post #260) the section of the Copenhagen Synthesis report on upper ocean heat content is prefectly clear about their meaning of an increase in the long term rate of accumulation of upper ocean heat as a result of reassessment taking into account instrumental measurement biases, and Pielke, while rejecting their statement, chose not to address this. It’s not really about a misunderstanding over \meaning\ in this case.
I’m not sure what you mean by this (and don’t bother answering if you don’t feel like it – I just want to clarify my position):
It’s quite likely that with a somewhat reduced radiative imbalance (sun at bottom of solar cycle) and strongish La Nina, that the last couple of years will yield upper ocean accumulated heat that is (temporarily) smaller than the long term trend. That’s what we’d expect. That’s not imcompatible with a continuing sea level rise which has both mass (land ice) and steric (ocean heat) components. The recent data (several papers cited in my post #204 and by sidd #236) indicates that there isn’t necessarily an incompatibility (as there seemed to be a year ago) between the independent measures of sea level rise and the calculated rise resulting from a summation of the steric and mass contributions to sea level, and in fact the steric (ocean heat) component continues to be significant. That’s what the scientific evidence indicates in my view.
“Models, either statistical,fundamental, or a combination of both are limited by our lack of underestanding of the fundamental processes and the accuracy of the data that we try to model.”
The randomness on any one day is evened out when you turn it into climate.
To that extent, climate is MUCH easier than weather to predict.
After all, if climate were so hard, how come atlases have “average temperature” and “average rainfall” in their statistics on a region and yet don’t update them each year?
#264 steve:
“Hopefully I can leave it at that because I suspect getting any more involved in this argument will cause me to lose a very valuable resource in answering some of my questions.”
You’re a model of decorum. I don’t think you have anything to fear on that account.
L. David Cooke wrote in 243:
Sorry about not responding sooner. I was getting wrapped up a bit in a new book that an acquaintance has coming out on the role of viruses in the evolution of life — and digging into the origins of early type II introns from which later type II introns, spliceosomal introns and retroviruses appear to have evolved. (The answer appears to lie in retroplasmids similar to the Mauriceville retroplasmid, although it is complicated by the mobility of type II introns, including their lateral transmission by plasmids and the exchange of genetic material between plasmids and their bacterial hosts. But I am no expert, and simply relying upon the technical papers I find on the web.)
The role of the deeper penetration of electromagnetic energy into the ocean as opposed to land makes a great deal of sense. I assume that the same would apply to visible light as well which would be more significant in the sense that the peak of the solar spectrum is in the visible range, but perhaps less significant to the extent that visible light, particularly the lower, less energetic end of the spectrum (e.g., red light) will tend to get absorbed closer to the surface?
However, another thought comes to mind. Solid matter will be rigid, and as such will not result in the circulation of heat due to the movement of matter itself. Porous solid matter such as soil will be less conducive to conduction. Both of these will result in heat being kept closer to the surface rather than smeared out in the layers below — although given borehole measurements clearly there is some smearing which is more or less a linear function of depth.
But in the case of the oceans there is circulation, and not all of that circulation is due to convection. Much is due to tidal motion where the motion itself will be inversely proportional to the distance from the surface. This will result in thermal energy penetrating more deeply into the the ocean, smearing out the thermal energy and resulting in a lower temperature at the surface even after equilibriation. Or so I would assume. Then again, tidal motion also travels along the bottom of the ocean, and the breaking of such waves occurs there as well — which should result in further heat transport there as well.
In any case thank you again. You have given me more to think about, which is pretty much always a good thing.
Fred Haynie says, “A really good model should be able to predict both weather and climate changes.”
Uh, given that weather is demonstrably chaotic, good luck with that. So, if you apply your logic to investing, I’d guess you’d be running to sell about now. After all, no model predicted the day-to-day behavior of the stocks. Did you even think about that statement before you wrote it?
[Response: Actually, this isn’t as bad an idea as you think. The basic code is very similar – the differences are in the initialisation and kind of experiment that is run. Standard climate models can be used in weather forecast mode if set up appropriately – though the weather forecasts are generally worse because the resolution is not as good, and the skill scores for this process have not been the key target over time. On the other hand, running weather models as if they were climate models doesn’t work very well either – turns out there are usually a lot of small terms that aren’t important for a few days, but make large differences to the climatology. – gavin]
Thanks Doug, I appreciate the comment.
Further to gavin’s response to 274, isn’t the reason why the UK Met Office model is called the “Unified Model” is because it’s the same model for weather and climate, so a unified code base.
I can’t find it on their website any more, but it used to say it. It may be that “the UM” is now so well known they don’t think they need to tell people about it.
However, the limit of forecast for the weather is still dominated by chaos rather than the calming influences of averaging and accumulation, so your calculating ability is vastly different.
Rob asks: “How is it possible to distinguish a sinking coral atoll from rising sea level. I mean all atolls are doomed, sooner or later they’ll all be submerged.”
You can see if the sea level is rising or the ground level lowering.
I mean, it’s only a stab in the dark, but that would me MY guess…
Could you not google for this first? It’s not like it’s a hot topic for climate denial debate, so it should be fairly easy to spot a good link.
Fred states: “My distiction between weather and climate is a matter of resolution with both respect to time and space”
There’s a fair bit more difference.
It doesn’t matter TOO much about solar flares when it comes to weather. Over the time of a *weather* forecast, there’s not a lot of change there.
Then again, climate doesn’t really care that there’s more rain on a weekend, because it adds up all the weekends and looks for trends.
Cloud formation is ESSENTIAL to getting good weather forecasts. It makes a BIG difference to the temperature and no cloud equals (near enough) no rain.
Getting its average effect is all that’s needed for climate forecasts.
The weather doesn’t really care about CO2 causing warming.
Climate does.
“What becomes important” is what makes the biggest change to predicting climate right and predicting weather right.
I know I’m coming to this rather late, but can someone please explain to me, or point me to an explanation on, what is the effect of the inverse barometer correction on a near-global sea level data set like this.
I am aware of the science behind the inverse barometer correction on smaller scales: surface pressure is a boundary condition for the pressure field in the ocean, so that at equilibrium a drop in surface pressure would require a small rise in sea level to maintain a zero horizontal pressure gradient.
However a change in surface pressure over the global ocean as a whole (as might be caused by a shifting in atmospheric mass from over the oceans to over the land, or vice versa) would not raise global sea level, which is constrained by global ocean volume.
However, there’s another “however” to consider: the satellite altimeters don’t work all the way to the poles (do they stop at 70 deg N & S?). So an exchange in atmospheric mass between the circumpolar regions and the mid-latitudes, will also affect the sea level, and in this case the sea level can adjust to it.
So has anyone assessed whether the inverse barometer correction on the CU sea level dataset really does improve its estimate of the quantity we really want, which is global ocean volume?
RE: 273
Hey Timothy Chase,
Sorry for possible mis-communication in regards to the radiative versus convective statement. Generally, I was suggesting the land/air versus sea/air interface. The point being that most of the heat released by dry land would be primarily by radiative transmission where most of the heat released by the ocean would be convective transmission, in to the atmosphere.
(The only difference would be the release of heat by moist land versus dry land, which suggests that if droughts were to increase there would be a higher tendency for the land to retain more heat then the ocean for a given surface area.) This in part plays into the discussion of regional deviation of the Jet Stream and the deviation of Rossby waves, which is a topic for another day…
As to internal turn over within the masses, granted the ocean will more likely model the atmosphere; however, it would likely be inverted as the troposphere is primarily warmed from the bottom and the ocean mainly from the top. (In essence, you have the “burner” heat bubbling up through the pot of one and you are trying to “broil” heat into the pot of the other…)
Cheers!
Dave Cooke
PS: As to viral evolution acting as the primary driver, it is entirely possible that short RNA strings may have affected the mitochondrial more so then the nucleolus DNA. http://en.wikipedia.org/wiki/Mitochondrial_DNA 7/6/2009
(Now it would be interesting to see the radiative source and its participation in either mutation or the creation of free agent RNA strings. Is it possible that the lack of pre-stratospheric ozone allowed UVA through, which attacked Blue Green bacterial DNA forcing the mutation into the two separate kingdoms…?)
Dave
Mark:
http://www.metoffice.gov.uk/science/creating/daysahead/nwp/um.html
“The Met Office Unified Model (UM) is the numerical modelling system developed and used at the Met Office. It is unique, because it has been designed to allow different configurations of the same model to be used to produce all our weather forecasts and climate predictions. The system has been in continual development since 1990…”
Pielke lost at least one subscriber to his blog when he said the decrease in sea ice has stopped, based on comparing 2008 figures to a 2009 figure that *does not exist yet* (the September minimum). Talk about not playing with a full deck—oops, I mean data set. (Anybody, please feel free to consider that ad hominem, heh heh.)
Sea level presentation, illustrated talk, much here:
http://www.clim-atic.org/documents/2009%20docs/Climate%20change%20and%20sea-level%20rise%20-%20Professor%20John%20Moore%20Arctic%20Centre.pdf
“Cloud formation is ESSENTIAL to getting good weather forecasts. It makes a BIG difference to the temperature and no cloud equals (near enough) no rain.
Getting its average effect is all that’s needed for climate forecasts.”
I’m not sure that’s really the whole story. It would be, if the effect was a one-way street but I don’t think it can be. Since clouds affect temperature and temperature affects clouds (plus a whole lot of other factors kicking in both ways and many of them not fully understood), there can’t be anthing like so easy as an “average effect”.
Ta. Hank.
bob, you need to get the AVERAGE effect right. Your climate model doesn’t care if there was heavy cloud outside St Pancreas station at 1400 on the 15th June or whether it was merely light cloud.
It does care if you can manage to get the proportion of heavy cloud close enough.
Mark #286
Maybe we mean the same thing. I guess the point is: how do you get the proportion of something like heavy cloud right (averaged over a grid cell) when the thing you’re looking for is a lot smaller than the cell itself, interacts heavily with all the other parameters traced, can move from one cell to another and can, when averaged, mean “one huge,deep cloud” as well as “many small, shallow clouds” which gives the same number but would still make a differnce for climate when systematically misjudged? My gut feeling is that cloud parameterization can only achieve so much but won’t really crack the problem with the way climate models work today. Unless clouds can be treated and traced as separate entities or objects, wandering on their own through grid cells and interact with them, they will probably remain one of the biggest sources of uncertainty. Frankly I don’t understand why that approach hasn’t been taken in the past – or maybe it has, failed and I simply couldn’t find it or there is an obvious reason for not doing so that I, not knowing anything about climate but just software development, am not aware of.
“I guess the point is: how do you get the proportion of something like heavy cloud right”
Actually, that’s one I do know about.
Microclimate studies.
You work out with VERY detailed physics and VERY SMALL boxes (rather like you do when designing the aerodynamics of fighter aircraft for the military) and work out “and what changes if we change THIS” over and over (and, I suspect, for the people who do this for a living, OVER, and OVER, …) again.
Then you run your model through a historical forecast test:
Get some weather start time in the past.
Run your model for some years.
Check the results against the weather observations over that period.
(the important bit here is that the data is in the past, so is OBSERVATIONAL EVIDENCE, but it isn’t used to tune your model parameters and therefore isn’t curve fitting, but a record you check your model against)
If it works our wrong, you try and think of how. Model that (from the physics) and try your even newer model.
“My gut feeling is that cloud parameterization can only achieve so much but won’t really crack the problem with the way climate models work today.”
The Greeks thought that the seat of reason was in the stomach and the head was just an organ for cooling the blood.
They were wrong.
Don’t listen to your gut, listen to your brain.
More papers available on sea level and climate on John Moore’s page, in addition to the very clear slideshow presentation that I linked recently above. It’d be good to focus on what’s really happening, rather than being distractible by kerfluffles in the bogusphere.
It’s generous of the authors to make full text available
http://www.ulapland.fi/home/hkunta/jmoore/johnarticles.html
a few recent ones that might be worth a look, links in original page:
102. Moore, J. C., A. Grinsted, and S. Jevrejeva (in Press) Wavelet-lag regression analysis of Atlantic tropical cyclone dependence on ENSO and Atlantic thermohaline variability Proceedings of the 1st International Summit on Hurricanes and Climate Change., J.B. Elsner & T. Jagger (Eds.), Springer
96. Jevrejeva, S., J.C. Moore, A. Grinsted and P.L. Woodworth (2008) Recent global sea level acceleration started over 200 years ago, Geophysical Research Letters, 35, L08715, doi:10.1029/2008GL033611.
95. Moore, J. C., A. Grinsted, and S. Jevrejeva (2008), Gulf Stream and ENSO increasing the temperature sensitivity of Atlantic tropical cyclones, Journal of Climate. 21 (7) 1523-1531
94. Jevrejeva, S., J.C. Moore and A. Grinsted, (2008) Relative importance of mass and volume changes to global sea level rise, Journal of Geophysical Research 113, D08105, doi:10.1029/2007JD009208.
“Don’t listen to your gut, listen to your brain.”
Yes, very funny. But all you’re saying in #288 is that the parameterization for wide grid GCMs haven’t been created from thin air but arrived at through some sort of high resolution modelling, probably verified using sattellite cloud object data and other observations. Well, I guessed that (with my brain) anyway. However the question is not how the parameterization has been calculated. The question is whether parameterization (thus “averaging” the effects of and on clouds in relatively large areas) is the best way to model clouds in a GCM.
“The question is whether parameterization (thus “averaging” the effects of and on clouds in relatively large areas) is the best way to model clouds in a GCM.”
Is that question the best way to improve GCM’s?
Talking of bupkis, Gavin, you may want to check what your words are being twisted to:
http://www.bbc.co.uk/blogs/thereporters/richardblack/2009/06/climate_meltdown_yet_fusion_la.html#P82584576
Mark #292
Answering it would be a start. I’m aware that you obviously can’t and/or don’t want to, so don’t bother and leave it to somebody else.
It’s basically the only way on a global scale given today’s computers, because of the combinatorial explosion of computations required as the size of the grid “boxes” shrink. As I understand it, from reading some model explanations available from the UK Met office, cloud phenomena are smaller than the grid size currently used.
As computers get faster, grid size can be shrunk, and have been shrinking over the last 20 years (when Hansen was running his early models in the 1980s even the supercomputers of the day were puny by today’s standards). Then more stuff can be physically modeled at the resulting higher spacial and temperal resolution.
This totally ignores the increasing state of physical knowledge that can be reflected in models, My guess is that the combinatorial explosion of computations that results when one shrinks the grid far outweighs the costs of incorporating new physics when processing an individual grid during each time step, but I am *only* guessing.
Bottom line, though – more spacial and temporal resolution and physics in the model, the more time spent watching lights blink and the electricity bill soar until you get a new computer that’s significantly faster. Then you can improve things and wait for the next new fast computer to come along.
ReCaptcha – what the signers of the Declaration were hoping for if they lost the Revolution: 1776 acquited.
On June 26, 2009, a person named Kimberly Strassel wrote an article in the WSJ called THE CLIMATE CHANGE CLIMATE CHANGE. She made a number of interesting claims:
1. A growing number of … scientists … once again doubt the science (of AGW).
2. The Polish Academy of Science has just come out against AGW.
3. The number of skeptics is swelling.
4. Sen Jim Inhofe now counts 700 scientists who disagree …
5. Ivar Giaever, a Nobel Prize winner (physics) decries AGW as “The New Religion.”
6. The earth’s temperature has flatlined since 2001.
7. Credit for much of this goes to Dr. Ian Plimer.
Kim’s email address (in the WSJ so it is public) is kim@wsj.com
Her call is for scientists to re-engage on the science.
The WSJ gets read by a lot of influential people.
Burgy (who does not subscribe to any of the above).
Bobberger, you know why parameterization is done?
http://www.google.com/search?q=define%3Aparameterization
# The representation of physical effects by simplified parameters in a computer model rather than by computing them dynamically
en.wiktionary.org/wiki/parameterization
# parameterize – Alternative spelling of parametrize
en.wiktionary.org/wiki/parameterize
# A technique that modelers employ to replace highly complex climatic processes or processes that occur on too small scales to be fully represented …
http://www.csa.com/discoveryguides/models/gloss.php
# This refers to the technique in climate models of representing processes that can’t be resolved by the dynamic physics of the model, or that …
http://wikiadapt.org/index.php
http://www.google.com/search?q=best+enemy+good
“3. The number of skeptics is swelling.”
How could it? After all the Oregon Petition had 31,000 climate scientists signing it and it was all skeptics, compared to the 800 on the side of the IPCC!
How many climate scientists does the world HAVE!!!!
“I’m aware that you obviously can’t and/or don’t want to, so don’t bother and leave it to somebody else.”
I am willing to, but you merely ask questions and *assume* they are important.
You say “this is not known” and *assume* that this makes a difference.
You say “this needs to be answered” but refuse to prove why it must.
Answer the questions raised by your insistence.
If you don’t know, how do you know they MUST be answered?
“Unless clouds can be treated and traced as separate entities or objects, wandering on their own through grid cells and interact with them, they will probably remain one of the biggest sources of uncertainty.”
But the eating habits of a single soldier in the army doesn’t stop logistics from keeping their men fed and supplied.
Even though the food such a soldier needs depends on what he’s done that day, how he’s interacted with his allies and his enemies.
But logistics uses an average soldier.
Not that specific soldier.
And they seem to do OK with it.
Are you SURE that what you say is necessary?
Another example.
Ideal gas laws.
They are the result of literally countless particles all running around at different speeds. No single atom or molecule is tracked.
Yet we get VERY good numbers for using in real applications where accuracy is important by considering them as an “average” and “a range” rather than “this atom here…” and tracking it through the gas.
Are you SURE your requirements are needed?