This last week has been an interesting one for observers of how climate change is covered in the media and online. On Wednesday an interesting paper (Thompson et al) was published in Nature, pointing to a clear artifact in the sea surface temperatures in 1945 and associating it with the changing mix of fleets and measurement techniques at the end of World War II. The mainstream media by and large got the story right – puzzling anomaly tracked down, corrections in progress after a little scientific detective work, consequences minor – even though a few headline writers got a little carried away in equating a specific dip in 1945 ocean temperatures with the more gentle 1940s-1970s cooling that is seen in the land measurements. However, some blog commentaries have gone completely overboard on the implications of this study in ways that are very revealing of their underlying biases.
The best commentary came from John Nielsen-Gammon’s new blog where he described very clearly how the uncertainties in data – both the known unknowns and unknown unknowns – get handled in practice (read that and then come back). Stoat, quite sensibly, suggested that it’s a bit early to be expressing an opinion on what it all means. But patience is not one of the blogosphere’s virtues and so there was no shortage of people extrapolating wildly to support their pet hobbyhorses. This in itself is not so unusual; despite much advice to the contrary, people (the media and bloggers) tend to weight new individual papers that make the news far more highly than the balance of evidence that really underlies assessments like the IPCC. But in this case, the addition of a little knowledge made the usual extravagances a little more scientific-looking and has given it some extra steam.
Like almost all historical climate data, ship-board sea surface temperatures (SST) were not collected with long term climate trends in mind. Thus practices varied enormously among ships and fleets and over time. In the 19th Century, simple wooden buckets would be thrown over the side to collect the water (a non-trivial exercise when a ship is moving, as many novice ocean-going researchers will painfully recall). Later on, special canvas buckets were used, and after WWII, insulated ‘buckets’ became more standard – though these aren’t really buckets in the colloquial sense of the word as the photo shows (pay attention to this because it comes up later).
The thermodynamic properties of each of these buckets are different and so when blending data sources together to get an estimate of the true anomaly, corrections for these biases are needed. For instance, the canvas buckets give a temperature up to 1ºC cooler in some circumstances (that depend on season and location – the biggest differences come over warm water in winter, global average is about 0.4ºC cooler) than the modern insulated buckets. Insulated buckets have a slight cool bias compared to temperature measurements that are taken at the inlet for water in the engine room which is the most used method at present. Automated buoys and drifters, which became more common in recent decades, tend to be cooler than the engine intake measures as well. The recent IPCC report had a thorough description of these issues (section 3.B.3) fully acknowledging that these corrections are a work in progress.
And that is indeed the case. The collection and digitisation of the ship logbooks is a huge undertaking and continues to add significant amounts of 20th Century and earlier data to the records. This dataset (ICOADS) is continually growing, and the impacts of the bias adjustments are continually being assessed. The biggest transitions in measurements occurred at the beginning of WWII between 1939 and 1941 when the sources of data switched from European fleets to almost exclusively US fleets (and who tended to use engine inlet temperatures rather than canvas buckets). This offset was large and dramatic and was identified more than ten years ago from comparisons of simultaneous measurements of night-time marine air temperatures (NMAT) which did not show such a shift. The experimentally-based adjustment to account for the canvas bucket cooling brought the sea surface temperatures much more into line with the NMAT series (Folland and Parker, 1995). (Note that this reduced the 20th Century trends in SST).
More recent work (for instance, at this workshop in 2005), has focussed on refining the estimates and incorporating new sources of data. For instance, the 1941 shift in the original corrections, was reduced and pushed back to 1939 with the addition of substantial and dominant amounts of US Merchant Marine data (which mostly used engine inlets temperatures).
The version of the data that is currently used in most temperature reconstructions is based on the work of Rayner and colleagues (reported in 2006). In their discussion of remaining issues they state:
Using metadata in the ICOADS it is possible to compare the contributions made by different countries to the marine component of the global temperature curve. Different countries give different advice to their observing fleets concerning how best to measure SST. Breaking the data up into separate countries’ contributions shows that the assumption made in deriving the original bucket corrections—that is, that the use of uninsulated buckets ended in January 1942—is incorrect. In particular, data gathered by ships recruited by Japan and the Netherlands (not shown) are biased in a way that suggests that these nations were still using uninsulated buckets to obtain SST measurements as late as the 1960s. By contrast, it appears that the United States started the switch to using engine room intake measurements as early as 1920.
They go on to mention the modern buoy problems and the continued need to work out bias corrections for changing engine inlet data as well as minor issues related to the modern insulated buckets. For example, the differences in co-located modern bucket and inlet temperatures are around 0.1 deg C:
(from John Kennedy, see also Kent and Kaplan, 2006).
However it is one thing to suspect that biases might remain in a dataset (a sentiment shared by everyone), it is quite another to show that they are really have an impact. The Thompson et al paper does the latter quite effectively by removing variability associated with some known climate modes (including ENSO) and seeing the 1945 anomaly pop out clearly. In doing this in fact, they show that the previous adjustments in the pre-war period were probably ok (though there is substantial additional evidence of that in any case – see the references in Rayner et al, 2006). The Thompson anomaly seems to coincide strongly with the post-war shift back to a mix of US and UK ships, implying that post-war bias corrections are indeed required and significant. This conclusion is not much of a surprise to any of the people working on this since they have been saying it in publications and meetings for years. The issue is of course quantifying and validating the corrections, for which the Thompson analysis might prove useful. The use of canvas buckets by the Dutch, Japanese and some UK ships is most likely to blame, and given the mix of national fleets shown above, this will make a noticeable difference in 1945 up to the early 1960s maybe – the details will depend on the seasonal and areal coverage of those sources compared to the dominant US information. The schematic in the Independent is probably a good first guess at what the change will look like (remember that the ocean changes are constrained by the NMAT record shown above):
Note that there was a big El Niño event in 1941 (independently documented in coral and other records).
So far, so good. The fun for the blog-watchers is what happened next. What could one do to get the story all wrong? First, you could incorrectly assume that scientists working on this must somehow be unaware of the problems (that is belied by the frequent mention of post WWII issues in workshops and papers since at least 2005, but never mind). Next, you could conflate the ‘buckets’ used in recent decades (as seen in the graphs in Kent et al 2007‘s discussion of the ICOADS meta-data) with the buckets in the pre-war period (see photo above) and exaggerate how prevalent they were. If you do make those mistakes however, you can extrapolate to get some rather dramatic (and erroneous) conclusions. For instance, that the effect of the ‘corrections’ would be to halve the SST trend from the 1970s. Gosh! (You should be careful not to mention the mismatch this would create with the independent NMAT data series). But there is more! You could take the (incorrect) prescription based on the bucket confusion, apply it to the full global temperatures (land included, hmm…) and think that this merits a discussion on whether the whole IPCC edifice had been completely undermined (Answer: no). And it goes on – once the bucket confusion was pointed out, the complaint switched to the scandal that it wasn’t properly explained and well, there must be something else…
All this shows wishful thinking overcoming logic. Every time there is a similar rush to judgment that is subsequently shown to be based on nothing, it still adds to the vast array of similar ‘evidence’ that keeps getting trotted out by the ill-informed. The excuse that these are just exploratory exercises in what-if thinking wears a little thin when the ‘what if’ always leads to the same (desired) conclusion. This week’s play-by-play was quite revealing on that score.
[Belated update: Interested in knowing how this worked out? Read this.]
Politics will always be the way we get things done when we work with people (gr=polis). However, politics can be motivated by either ignorance or science. Eventually, I don’t see any way around it but to build a smarter voter. If that means we have to take American Idol of the air, so be it.
The current breed of denialists are not motivated by facts, so it will not matter how strong the case is for climate change. However, on a positive note, a recent poll revealed that most young women would rather talk to a guy at a party with the latest green car than to a guy with a sports car.
Geoff,
You wrote:
You can leave my country, Australia, off the list. Please don’t invent to make a point. Stick to what you know is measured accurately, both as to desertification and fires, and quote your source.
You may wish to declare your Australia a global warming free zone but …
Understanding autumn rain decline in SE Australia http://www.csiro.au/news/UnderstandingDeclineAutumnRain.html
“This is the worst bush fire conditions we have ever had in Victoria’s history …”
http://www.sott.net/articles/show/125695-Wildfires+Burn+in+Southern+Australia
Australia suffers worst drought in 1,000 years
Depleted reservoirs, failed crops and arid farmland spark global warming tussle
http://www.guardian.co.uk/world/2006/nov/08/australia.drought
Cheers, Alastair.
Roger Pielke Sr. chimes in –
http://climatesci.org/2008/06/03/biased-view-of-the-global-average-temperauture-trend-data-at-real-climate/
https://web.archive.org/web/20080703104834/http://climatesci.org/2008/06/03/biased-view-of-the-global-average-temperauture-trend-data-at-real-climate/
[Response: And another example of someone over-extrapolating from the Thompson et al paper in order to promote their pet hobbyhorse. Pretty much underlines the point of my post I think. – gavin]
Geoff Sherrington (#48):
Although desertification and fires are related in that they are both exacerbated by increasing average temperatures, I agree that they are not directly related (here in Australia at least) in the manner of fires causing deserts. Desertification on this continent is more the result of land clearance, broad-acre agriculture and grazing in arid and semi-arid regions.
However, if you want information on the impact of climate change and associated temperature rise on fires, then this report by the CSIRO is a good place to start:
Hennessy K, Lucas C, Nicholls N, Bathols J, Suppiah R, Ricketts J. 2006. Climate change impacts on fire-weather in south-east Australia. CSIRO, Australia. [PDF file, 2MB, 91 pages].
I’ve been watching these NESDIS arctic ice images:
Here’s the residual ice at the end of last year’s melt season:
By the start of this year, there was clearly multi-year ice north of Greenland and the Canadian archipelago, and thin ice everywhere else apart from in a narrow band stretching roughly from NE Greenland to Severnaya Zemlya:
The transpolar drift has steadily moved that band, and much of the rest of the multi-year ice, towards the Fram Strait:
Today the band is broken. Using this very imperfect observation, I suggest that for the first time in history there is no multi-year ice between the pole and the Fram Strait.
To get a really clear impression of the process, I recommending opening each of these images in a separate browser tab and using Ctrl-Tab to cycle through them.
Argh. Links broken in my comment #55. Here are the images:
End of last melt season:
http://manati.orbit.nesdis.noaa.gov/ice_image21/2007/D07250.NHEAVEH.GIF
Start of this year:
http://manati.orbit.nesdis.noaa.gov/ice_image21/D08001.NHEAVEH.GIF
Movement earlier this year:
http://manati.orbit.nesdis.noaa.gov/ice_image21/D08050.NHEAVEH.GIF
http://manati.orbit.nesdis.noaa.gov/ice_image21/D08100.NHEAVEH.GIF
Today’s image:
http://manati.orbit.nesdis.noaa.gov/ice_image21/D08154.NHEAVEH.GIF
RE: #30
What type of thermometers were used for these measurements? I can’t imagine a merchant vessel using high-quality scientific types. How were these calibrated? Or are there special thermometers for marine service?
Re # 57 Harold Pierce, Jr.
Interesting question. I am curious to know how the Navy’s methods during war time (or even in rough seas) compare with the meticulous methods used by oceanographers (Woods Hole oceanographers, at least):
Nansen-Bottle Stations at the Woods Hole Oceanographic Institution
Corresponding author: Bruce A. Warren
Abstract
Nansen-bottle stations were occupied by ships and personnel of the Woods HoleOceanographic Institution from 1931 to about 1981. Most of these data are in archives, but usingthem intelligently to depict the state of the ocean and to assess time changes in it requiresknowing how the observations were made, what accuracies can be assigned to them, and generally how to approach them. This report describes the evolving methods on Woods Hole stations for measuring temperature, depth of observation, salinity, and dissolved-oxygen concentration, and for determining station position. Accuracies generally improved over time,although estimates from the early years are sparse, and even later there is indefiniteness.Analytical error is to be distinguished from sloppy sample collection and other blunders. The routine for carrying out Nansen-bottle stations, from the late 1950s through the 1970s, is reviewed.
http://64.233.169.104/custom?q=cache:tW194mlD1s8J:https://darchive.mblwhoilibrary.org/bitstream/1912/1691/3/Nansen_Bottles.pdf+Nansen+Bottle&hl=en&ct=clnk&cd=13&gl=us&client=pub-2456819124576563
Gavin – Since you are willing to listen to those who have worked with the data, I invite you to answer the weblog on Climate Science today: http://climatesci.org/2008/06/03/biased-view-of-the-global-average-temperauture-trend-data-at-real-climate/
I look forward to you showing that the claim that Real Climate is biased is incorrect.
[Response: Roger, you are not going to be convinced until we agree with everything you think is important. Since that isn’t going to happen, there doesn’t seem to be much point in engaging. I’m perfectly willing to accept that you have different priorities and interests than us and would not dream of curtailing your right to blog about any of them. For instance, should I assert that you are biased because you haven’t blogged about any of my recent papers? I think not. I would expect the same courtesy from you. – gavin]
RE: #58
I once saw the term “Kriegsmarine effect”. Presumably it has something to do with the German Navy. Do you know anthing about this?
There is a huge amount merchant shipping still discharging much oily bilge water into the open ocean. Oil on the surface of water would retard its evaporation. Cruise ship can’t do this anymore and have to filter the bilge water to remove oil before discharing it into the ocean.
Confused by your response Gavin. You strongly imply that it is not responsible to say these data problems are a big deal. Pielke says the are a big deal, and he provides an analysis to suggest this accounts for a very significant amount of IPCC warming trend.
If Pielke is right are you seriously saying that finding about SSTs would not be a big deal? Why not address the issue rather than spend all this time asserting it’s not relevant?
[Response: You are confusing your Pielkes (it’s easily done). Jr is the one with the trends based on nothing originally, and based on a little something later. Why I should waste time discussing the implications of hypotheses that are certainly incorrect is unclear. All I said above is that the corrections are likely to be limited to the immediate postwar period (based on the paper itself and discussions with people in a position to know). If so, this has little or no relevance to the detection or attribution of climate change and thus no importance to the main IPCC conclusions. Is it meaningful? Of course, but meaning is not limited to the IPCC AR4 SPM. I suggested a wait and see attitude is more appropriate – others appear to disagree. We’ll see who is vindicated when the new analyses are done. – gavin]
Re #56: Nick, what’s the URL for selecting those images, and is there any sort of interpretation guide? Thanks.
Re # 60 Harold Pierce
Kriegsmarine means “war navy”
(http://en.wikipedia.org/wiki/Kriegsmarine). I don’t know what the Kriegsmarine effect is, but when I googled it I came up with this essay by AGW skeptic, Roy Spencer, of the National Space Science and Technology Center at University of Alabama, Huntsville:
Spencer Part2: More CO2 Peculiarities – The C13/C12 Isotope Ratio
http://wattsupwiththat.wordpress.com/2008/01/28/spencer-pt2-more-co2-peculiarities-the-c13c12-isotope-ratio/
I couldn’t find any mention of Kriegsmarine effect, though I didn’t read it very carefully.
By the way, Spencer’s first article on this subject (Part 1) was titled: Atmospheric CO2 Increases: Could the Ocean, Rather Than Mankind, Be the Reason?
Gavin:
All I said above is that the corrections are likely to be limited to the immediate postwar period (based on the paper itself and discussions with people in a position to know). If so, this has little or no relevance to the detection or attribution of climate change and thus no importance to the main IPCC conclusions
Thanks for this clarification. In fact befor I had misread Pielke Sr. post as talking about SST anomolies when in fact he was looking at other things when he suggests IPCC is running too hot.
Steve Bloom @ 62: The images are scatterometry, QuikSCAT daily ice images. You can pick the images yourself from the directory view:
http://manati.orbit.nesdis.noaa.gov/ice_image21/
e.g. D08154.NHEAVEH.GIF: year 08, day 154, northern hemisphere average.
This page provides, and links to, more information about the instruments, data collection, and interpretation:
http://manati.orbit.nesdis.noaa.gov/cgi-bin/qscat_ice.pl
> Kriegsmarine
There’s a fellow who will be along any minute to fill you in on his theory. Or you’ll find it at a great many websites — oceanclimate.de and seaclimate.com among others.
Perhaps realclimate’s “bias” consists of reporting on what the papers actually say, rather than reporting on what they say and twisting it around to be some new attack on the IPCC and AGW…which the Pielkes seem to be joining the club for doing any chance they can get
Perhaps the authors would not have written this in the abstract:
//Corrections for the discontinuity are expected to alter the character of mid-twentieth century temperature variability but not estimates of the century-long trend in global-mean temperatures.//
Re 47 Timo
The Sun et al paper links the WV/cloud bias to ENSO rather than global warming. This is in their paper:
//”These results suggest that at least in the models, the feedbacks of water vapor and clouds estimated
from the ENSO cycle cannot be used as harbingers for the feedbacks of water vapor and clouds
during global warming.”//
Of course, as further evidence of “bias,” (RC’s of course) this didn’t stop Roger Pielke Sr. from declaring so confidently that
//”This study indicates that the IPCC models are overpredicting global warming in response to positive radiative forcing.”//
Silliness.
Re 59 – Gavin, I just read Roger’s response. He is really an annoying prima donna. “Dance with me, or you are rejecting the art of dance.” He does not understand that he does not understand. To use the words of a recent Secretary of Defense, he seems to be plagued by unknown unknowns.
Re. 33 “Hank Roberts wrote: “The dry dock, with 15 people on board, was adrift in heavy seas for 2 days before being taken back under tow by the Admiral Makarov on Oct 16.”
“and had trouble doing the job” (but is this in the NW passage itself or outside of it?) Is this your opinion or facts?
Note that it might not have been in the NW passage itself that was so bad…the “adrift event” took place off Nova Scotia…which I believe is not part of the infamous north west passage and the Cabot passage “is part of an important shipping route”:
“Cabot Strait, channel connecting the Gulf of St. Lawrence with the Atlantic Ocean, between Cape Breton Island and the island of Newfoundland, southeastern Canada. The channel is 110 km (70 mi) wide. It is part of an important shipping route. Ferries cross Cabot Strait, between Cape Breton Island and the island of Newfoundland. The channel is named after the Italian navigator John Cabot.”
http://encarta.msn.com/encyclopedia_761564151/Cabot_Strait.html
As Arch Stanton found:
“This use of the Passage to
avoid storms in the open ocean demonstrated
its advantage for international
shipping should the ice be reduced.
The fact that the dry dock was
then almost lost in a storm off Newfoundland
seemed to confirm the benefits
of sheltered waters of the Passage
route.”
http://www.navyleague.ca/eng/ma/papers/huebert_e.pdf
So Hank, I wonder if the Northwest Passage itself is really so difficult to navigate…or is it instead the usual shipping lanes that are so hard to navigate in comparison?
In other words, can you now just crank up an icebreaker and go through the NW passage and save ~3000 Km or 5000 miles while in a “calm NW passage”?
RE: #66
Hank, thanks for the links. Absolutely fascinating. Do you think that the enormous amount maritime activity with modern ships bigger than most WW II battleships could be having an effect on the oceans or some sections of the oceans. The authors of these articles seem to think so.
Their propellers of htese ships really churn up the sea. Essentially all of their heat energy is released into the ocean enviroment.
Google “P&O Ventura” This ship is just huge and boogles the mind.
Unlike naval vessels, merchant ships usually travel in well-defined sea lanes. Can the satellites see their effects? Know any links?
Gavin
Have you see this sentence at the end of the Thompson et al. article?
“However, compensation for a different potential source of bias in SST data in the past decade the transition from ship to buoy-derived SSTs ,might increase the century-long trends by raising recent SSTs as much as 0.1 °C, as buoy-derived SSTs are biased cool relative to ship measurements”
[Response: Yes. I mentioned it above. This would imply that the last few years in ths SST record is biased a little low – but as I said also, it’s probably best to wait and see how this plays out when all the new corrections are made. – gavin]
This bunch of sites promoting the naval war climate effect is probably the most bizarre stuff you can find on the entire web.
Anyway – I used it as an excuse to call my grandfather who is well into his nineties and spent WWII on a german submarine as an engineer. He said they had very sophisticated temperature measuring equipment on these ships but of course they never used it to detect the temperature as an absolute but for calibrating various sonar sensors on weapons and the ship itself. He also mentioned that they kept detailed records about the exact depth of temperature layers. Furthermore there apparently were seperate measurements for engine inlet and ballast water temperature used to finetuning the ship’s engine performance and diving behaviour but he doubted they would be much use in research due to lack of absolute calibration and lack of records. When I told him, why I wanted to know all this stuff, he answered that there should be nobody better positioned to know the exact water temperatures at any depth in any part of the oceans than the post-war US and russian sub fleets. Is that true and if so – are these records available for research and already in use for climate science? Considering the degree of sophistication on modern nuclear subs, they should be the most reliable and most traveled water termometers out there – they’re certainly the most expensive.
Re 47 Timo
maybe you are aware, that cloud types, properties, distribution, thickness, etc. in the tropics (that is, what the Sun paper is all about, see title) are different from those over the rest of the planet and might react different on global warming. ENSO forcing is not a very good analogon for global warming concerning clouds (as the authors assert).
Harold Pierce writes:
Do the math, Harold. The amount released is trivial compared to the ocean’s heat content, or even the upper ocean’s heat content.
Roger, in your post you complain, that RC has not commented on a specific paper.
Since it is not possible to comment on any published paper, this complaint is strange.
However, some short comments on your post http://climatesci.org/2008/01/30/a-serious-problem-with-the-use-of-a-global-average-surface-temperature-anomaly-to-diagnose-global-warming-part-ii/ for the readers here (comments on your site are closed), since it concerns my former research field:
The post claims a significant bias in global temperature trends due to a warm bias in nocturnal minimum temperature trends due to the stabilisation (positive temperature with height) of the nocturnal boundary layer during calm nights.
It presents a back-of-the envelope estimation of the possible influence of this bias since 1990.
This estimation has serious problems, e.g.:
1) The temperature trends presented in the IPCC report are based on monthly averages, which are calculated from continuous measurements for a lot of the stations, and not as assumed only from daily maximum and minimum temperatures, especially since 1990. Thus the influence of the daily minimum temperature is smaller than assumed.
2) The discussed problem (the formation of a nocturnal boundary layer) over mid-latitudes only occurs for a number of nights during summer, i.e. for perhaps 30-60 days a year. For stations in high latitudes it will be less, for those in the subtropics it will be more. However, this reduces the effect by a factor of 5-10.
3) The assumption, that in terrain with more relief this effect will be stronger, is strange. Relief causes winds in the discussed situations, which will reduce the effect. The effect is strongest in plains. Thus it concerns only part of the stations. This further reduces the effect.
In addition, there are more fundamental questions (e.g. the trends are about surface temperatures, so why bother about different trends at other heights).
Sorry, that I also have not the time to comment the paper more in depth.
Harold Pierce #71:
http://climateboy.blogspot.com/2007/10/shipping-lanes.html
and links therein
There must somewhere be explanation how eg GISS makes the global land & ocean temperature averages. Then it shouldn’t be a big deal to estimate how these bucket adjustments change the temperature series? The GISS is so often referred here in RC and by IPCC, which rely just on peer reviewed articles, that there must be a good description how the SST averages are calculated? And which stations are used, how station moves or changes are handled, how UHI effects are calculated and so on for the land stations. Any help?
[Response: http://data.giss.nasa.gov/gistemp though the ocean temperatures are a blend of the HadISST product and the satellites from 1982 onwards (Reynolds and Smith). – gavin]
#73
*OT apologies*
what a wonderful response from your grandfather – so acute and clear sounds like he is absolutely on the ball plus I would take his word (“is it true?”) over many others!!
> 73, Henning’s grandfather on submarine data
He’s right. Part of the US data set for the Arctic was declassified at the behest of then Senator Al Gore; the Navy has a large climate modeling program and publishes some work steadily. E.g.:
… The area first declassified is called the “Gore box” ….
https://www.realclimate.org/index.php/archives/2006/03/climate- …
https://www.realclimate.org/index.php/archives/2006/05/more-on-the-arctic/ –
… bear in mind that Maslowski has access to data that none of the other modelers have (the stuff outside the “Gore box”). …
fergusbrown.wordpress.com/2007/12/12/did-someone-stir-the-martini/
As a lay person (albeit with a Science degree) I find it interesting that the last 7 posts on this site have been disputing claims by Climate Change skeptics or data/studies that may/may not support their case. If the skeptics and their arguments are so off-the-wall why all the focus. “Doth the lady protest too much???”
When discussing sea surface temperatures please see the following new study about sea level rise:
Berge-Nguyen, M., A. Cazenave, A. Lombard, W. Llovel, J. Viarre, and J.F. Cretaux. 2008. Reconstruction of past decades sea level using thermosteric sea level, tide gauge, satellite altimetry and ocean reanalysis data. Global and Planetary Change Vol. 62, No 1-2, pp. 1–13, May 2008
They reconstructed approximately 80 mm sea level rise over 1950–2003, i.e. a rise of 1.48 mm yr−1. This rise is below the estimate of the IPCC and have no acceleration.
And after 2003 sea levels are falling…
Re 81. Gee, Patrick, why don’t you take that “science degree” off the shelf where it’s gathering dust and put it to some use learning the science yourself?
Perhaps you have been unaware of the well funded disinformation campaign waged by coal and oil interests to discredit good science and heap calumny on good scientists. Perhaps you are not outraged when ignorant food tubes distort science to support their own pet theories. Perhaps you don’t feel that civilization is under threat in a society where more people believe in angels than believe in evolution. On second thought, go ahead and put that science degree back on the shelf. You’ll never need it.
Urs – Thank you for taking the time to comment on the Climate Science weblog on the warm bias [http://climatesci.org/2008/01/30/a-serious-problem-with-the-use-of-a-global-average-surface-temperature-anomaly-to-diagnose-global-warming-part-ii/]. Here are the answers to your very good questions:
1. The monthly mean is obtained as the average of each daily maximum and minimum temperature, so that the warm bias is not reduced by averaging.
2. The nocturnal boundary layer occurs at all latitudes, of course, and in the higher latitudes persists 24 hours a day in the winter. At these high latitudes in the winter, where a significant wamring has been reported,the warm bias results in an overstatement of the warming.
3. In complex terrain, the lower elevations (closed valleys, depressions, ect) have cool air pooling when the synoptic wind and large scale pressure gradient are weak. This results in the stable boundary layer being a common feature, particularly in the winter at middle and high latitudes (e.g. such as the Grand Valley of Colorado).
The result of this warm bias is a significant overstating of the surface temperature warming.
Re 83. Ray,
instead of yr political comments on scientists, I see different scientific views in all details of Climatology, worth debatable with scientific courtesy.
In general, I see enormous amount of neutral, ‘mainstream’, alternative, critical and sceptical studies, normally funded and peer-reviewed.
Media and blogosphere are sui generi.
“squishy science”
Repeating what Gavin wrote “Every time there is a similar rush to judgment that is subsequently shown to be based on nothing, it still adds to the vast array of similar ‘evidence’ that keeps getting trotted out by the ill-informed.” …
Repepeating what longtime CBS WCCO-TV meteorologist Mike Fairbourne said recently – in the 1970s “we were screaming about global cooling. It makes me nervous when we pin a few warm years on squishy science.”
Fairbourne said he has talked “to a number of meteorologists who have similar opinions” as his, adding that he is concerned about “the extremism that is attached to the global warming.”
I think we need to be concerned about where meteorologists, and many people who listen to them, are getting their educations about climate change and global warming from. NOAA’s NWES meteorologists have made light of and poked fun of global warming for more than a decade, and counting?
http://www.startribune.com/nation/19095579.html?page=1&c=y
Re # 81 ” If the skeptics and their arguments are so off-the-wall why all the focus.”
Well, people tend to argue with those with whom they disagree – if there is no disagreement, there is little to argue about (unless you want to nitpick). Now, if you are asking, Why not ignore the AGW skeptics/deniers? it is simple: They (some of them, at least) wield influence far in excess of their scientific credibility on the issue, and some of them are hell-bent on misleading the public, as Ray has pointed out.
#73
Henning,
I would like to meet your grandfather and swap a sea story or two. He is a rare survivor of some of the harshest naval warfare on both sides in history. His memory sounds right on the money to me. I spent 15 years as a Cold Warrior, slinking around in much greater comfort on US nuclear submarines and then another 15 training submariners, maintaining the ships and planning their operations.
I cannot speak for the Soviet submarine data gathering practices but the US submariners logged everything. Strategic missile submarines put together extensive data packages after each approximately 60 day patrol. These included almost continuous comparisons of inertial velocity and electromagnetic log velocity. This gives a continuous measure of ocean current (set and drift). Daily XBT traces were taken which provided sound velocity profiles down to 1000 feet or more. At least daily traces of sound velocity from operating depths (a few hundred feet) to periscope depth were submitted. Continuous, highly accurate bottom contour traces were recorded. Sea water injection temperatures were logged hourly. All of this was coupled to very accurate continuous inertial navigation based positions.
Polaris patrols started in 1960 with much the same data gathering that, I think, continues to this day on Trident submarines. Well over 3000 patrols have been conducted. A patrol of 60 days would have between 9000 and 10000 miles of continuous track over chunks of the Norwegian Sea, North Atlantic or Mediterranean about the size of Texas. Similar patrols were conducted in the Pacific from 1964 on. Each data package was submitted for analysis to the Applied Physics Laboratory at Johns Hopkins University. The bottom line for the analysis was whether or not we had maintained continuous target coverage and the ability to launch within national command authority guidelines. Later the data packages were extended to cover more sonar system related data and used to develop better sonar and also confirm that we were not being followed by the “other guys”.
The data reduction effort would be enormous. I think the effort could provide good temperature data over an almost 50 year period and down to depths of at least 100 meters. The ocean current data is unique and should be a valuable input to ocean modeling. Best of all for me would be knowing we contributed to something beyond mutually assured destruction.
Declassifying this data will require strong political leadership—at least as strong as provided by Mr. Gore in breaking loose the Arctic ice data. I can think of no one better to take on this task then my own Representative Jay Inslee (D-Washington). He already has a stellar record on energy and climate.
Timo,
Different scientific views? Exactly where in the peer-reviewed literature is there any contention that CO2 sensitivity is significantly less than 3 degrees per doubling (other than, say the ill-fated attempt of a certain scientist from BNL).
Yes, there are areas where uncertainty remains. The role of CO2 is not among these. If you contend otherwise, produce the peer-reviewed literature backing your position.
Re 87 Chuck,
Science is not about credibility, but facts. When Climatology is mostly probabilities, there’s always room to debate.
Everyone, whether neutral, ‘mainstream’, alternative, critical or sceptical, who proclaims certainty, only proves poor knowledge, false confidence and lack of scientific understanding (& behavior).
#82, Timo, I can’t find that paper, but here are some related charts that show sea level rises overall, but thermal contraction since 2003, perhaps that’s what you were referring to?
http://www.aviso.oceanobs.com/en/news/ocean-indicators/mean-sea-level/science-questions/index.html
Yesterday’s Science Times section of the NY Times had a brief piece on this topic. http://www.nytimes.com/2008/06/03/science/03obtemp.html?ref=science
Also pack up all your cares and woes if you’re concerned about the future of renewables, especially solar power, the same section contains an article in which Dr. Ray Kurzweil says in part:
” Worried about greenhouse gas emissions? Have faith. Solar power may look terribly uneconomical at the moment, but with the exponential progress being made in nanoengineering, Dr. Kurzweil calculates that it’ll be cost-competitive with fossil fuels in just five years, and that within 20 years all our energy will come from clean sources.”
http://www.nytimes.com/2008/06/03/science/03tier.html?_r=1&ref=science&oref=slogin
Re 89. Ray,
about climate sensitivity please see e.g.
1. Kiehl, Jeffrey T., and Christine A. Shields, 2007. Inter-model climate sensitivity. NCAR Climate Change Prediction Program study 2007, online http://www.cgd.ucar.edu/ccr/shields/posters/ccppsensitivity.pdf
2. Kiehl, Jeffrey T., 2007. Twentieth century climate model response and climate sensitivity. Geophys. Res. Lett., 34, L22710, doi:10.1029/2007GL031383, November 28, 2007
Abstract
Climate forcing and climate sensitivity are two key factors in understanding Earth’s climate. There is considerable interest in decreasing our uncertainty in climate sensitivity. This study explores the role of these two factors in climate simulations of the 20th century. It is found that the total anthropogenic forcing for a wide range of climate models differs by a factor of two and that the total forcing is inversely correlated to climate sensitivity. Much of the uncertainty in total anthropogenic forcing derives from a threefold range of uncertainty in the aerosol forcing used (TH = tuned) in the simulations.
[edit – FUD removed]
5. Seiffert, Rita, and Jin-Song von Storch, 2008. Impact of atmospheric small-scale fluctuations on climate sensitivity. Geophys. Res. Lett., 35, L10704, doi:10.1029/2008GL033483, May 21, 2008
Abstract
Climate change scenarios are based on numerical models with finite spatial and temporal resolutions. The impact of unresolved processes is parameterized without taking the variability induced by subscale processes into account. This drawback could lead to an over-/underestimation of the climate sensitivity. The aim of this study is to investigate the impact of small-scale atmospheric fluctuations on the modeled climate sensitivity to increased CO2 concentration. Using a complex coupled atmosphere-ocean general circulation model (ECHAM5/MPI-OM) climate response experiments with enhanced small-scale fluctuations are performed. Our results show that the strength of the global warming due to a CO2 doubling depends on the representation of small-scale fluctuations. Reducing the horizontal diffusion by a factor of 3 leads to an increase of the equilibrium climate sensitivity by 13%. If white noise is added to the small scales, the climate sensitivity tends to weaken. The largest changes in responses occur in the upper troposphere.
[edit – irrelevant ref removed]
Not trying to hijack this thread:
“Our investigation found that during the fall of 2004 through early 2006, the NASA Headquarters Office of Public Affairs managed the topic of climate change in a manner that reduced, marginalized, or mischaracterized climate change science made available to the general public through those particular media over which the Office of Public Affairs had control (i.e., news releases and media access).
NASA internal review June 2008
“The report found credence in allegations that National Public Radio was denied access to top global warming scientist James Hansen. It also found evidence that NASA headquarters press officials canceled a press conference on a mission monitoring ozone pollution and global warming because it was too close to the 2004 presidential election.”
http://www.hq.nasa.gov/office/oig/hq/audits/reports/FY08/IG-08-017.pdf
#86 warm Northern re-greetings Pat, Being of Scottish ancestry, I rather go down fighting the good fight, than sit down and watch the show go bad, complacency rules the world, even people in key science positions follow the business as usual flow, but it does not mean we all have to agree to do nothing. Ya TV met guys have for the most part been horrendous on the subject for the longest time. They can’t distinguish the difference between climate and weather forecasting. We got a CBC weather woman who isn’t so bad, try watching CBC National news if you have access.
#84 Roger, Nice arguments, they are trivial at best, of no real consequence aside from flaunting semantics. Why don’t you do a weighted temperature of your Colorado Upper Air Radiosondes, Over the last 3 months, and see if there is a noticeable variation? Just wondering if you have a bit of access, and a bit of curiosity? You may be surprised by what you find.
Thanks so much for the fascinating Maritime Archeo-Climatology.
This triggers a thought that there must be a huge amount of data in airline pilot reports. I know that every aircraft has a high quality thermometer or even two or more. And at any moment, there are thousands of aircraft in flight somewhere globally. Sometimes pilots report weather info. With aircraft transponders reporting other data, Shouldn’t all aircraft report temperature too? Seems like an easy way to collect data. And there might be lots of data to mine.
> Aircraft
Sounds like special instruments would be preferable, avoiding people blogging about how the Boeing 737 thermometers were known biased and the Airbus temperature gauges were placed downwind of the engines….
But it’s being tried:
“… Moffett Field isn’t generally open to civilian aviation. To get access, Google’s founders, Larry Page and Sergey Brin, along with CEO Eric Schmidt, agreed to pay $1.3 million annually to NASA through a holding company they control and to carry scientific instruments aboard their aircraft….”
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/11/15/BU85SK0QM.DTL
I imagine the radio call.
“Hello, Sergei? Moffett here. We’re diverting your Hawaii vacation flight by a couple hundred miles to get better data on that hurricane offshore of Baja before it hits San Diego. Yes, hurricane. No, you’ll be fine. Fasten your seat belts, this may be a bit bumpy …”
Or imagine hundreds of North Atlantic or polar flights — at very specific altitudes and routes – and altimeters are pretty accurate. How about 50 years of temperature data at 30,000 feet? Different planes and different hardware is similar to the bucket problem above. The data may be there in the past, certainly so in the future. Looks like a straight forward study.
Re # 90 Timo
Most scientific “facts” are accepted as such based on probability – that’s the reason scientists perform, and report, statistical analysis of their data. And virtually all scientific conclusions are debatable (though some are so thoroughly confirmed that further debate is of little value). In this regard, climatology is no different from any other field of science. Surely you know all of this?
As for credibility, in order to avoid having to repeat every scientific study myself, I have to rely on research conducted by others in order to advance my knowledge. So, I have to mentally assign a degree of credibility to the papers I read, and to the authors of those papers. I’m much more willing to accept the findings of well-credentialed authors publishing in reputable, peer-reviewed journals. For the same reason, I am inclined to accept the information reported at RC based on the scientific reputations of the contributors. I know full well,however, that any given statement, or any given conclusion, by any of the RC contributors could be partially or completely wrong. But, I have far more confidence in their statements than I do of many of the authors at other climate science websites. Roy Spencer, S. Fred Singer, Roger A Pielke, Sr., and others may well make valid contributions to the field of climatology, but I am inclined to view their statements with skepticism, at least until I see their views confirmed in the peer-reviewed literature. Though, S.Fred Singer’s assertion in an ABC news interview that it never occurs to him that he might be wrong on AGW convinced me that he merits no credibility as a scientist.
If you have followed the AGW debate in the blogosphere and in the popular press, you are well aware that there is a lot of misinformation being published, some of it intentionally. Nationally (U.S.) syndicated columnists George Will and Charles Krauthammer both had op-ed essays published during the past week, in which they continued to advance their skepticism about AGW – they clearly are not getting their “facts” from the peer-reviewed climatology literature, and they are clearly not reading RC. So, the question is, where are they getting their information? Very likely it is the small number of AGW skeptics with science Ph.D.s whose views receive widespread attention in the media and blogosphere but somehow don’t make it into the peer-reviewed literature (or, what they publish in the peer-reviewed literature is not what gains them a following of AGW skeptics and deniers).
It is those authors, whose influence in the blogosphere and mass media outweighs their scientific credentials (and publication record) in the field of climatalogy, that are the subject of many of the RC posts – the RC contributors are trying to set the record straight. Patrick’s question(# 81) is either disingenuous or he is remarkably ill-informed.
Re: #82 on sea level rise.
That paper doesn’t appear to be available (for free) on line, but the abstract is. See the following link:
http://www.science-direct.com/science?_ob=ArticleURL&_udi=B6VF0-4RC2NPR-1&_user=10&_coverDate=05%2F31%2F2008&_rdoc=1&_fmt=high&_orig=browse&_srch=doc-info(%23toc%235996%232008%23999379998%23687592%23FLA%23display%23Volume)&_cdi=5996&_sort=d&_docanchor=&_ct=13&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=2116d200a8f96f26d3a37d50865c3061
The abstract states:
“This study investigates past sea level reconstruction (over 1950–2003) based on tide gauge records and EOF spatial patterns from different 2-D fields. In a first step, we test the influence on the reconstructed signal of the 2-D fields temporal coverage. For that purpose we use global grids of thermosteric sea level data, available over 1950–2003. Different time spans (in the range 10–50 yr) for the EOF spatial patterns, and different geographical distributions for the 1-D thermosteric sea level time series (interpolated at specific locations from the 2-D grids), are successively used to reconstruct the 54-year long thermosteric sea level signal. In each case we compare the reconstructed trend map with the reference. The simulation indicates that the longer the time span covered by the spatial EOFs, the closer to the reference the reconstructed thermosteric sea level trends. In a second step, we apply the method to reconstructing 2-D sea level data over 1950–2003, combining sparse tide gauge records available since 1950, with EOF spatial patterns from different sources: (1) thermosteric sea level grids over 1955–2003, (2) sea level grids from Topex/Poseidon satellite altimetry over 1993–2003, and (3) dynamic height grids from the SODA reanalysis over 1958–2001. The reconstructed global mean sea level trend based on thermosteric EOFs (case 1) is significantly lower than the observed trend, while the interannual/decadal sea level fluctuations are well reproduced. Case 2 (Topex/Poseidon EOFs over 1993–2003) leads to a global mean sea level trend over the 54-year time interval very close to the observed trend. But the spatial trends of the reconstruction over 1950–2003 are significantly different from those obtained with thermosteric EOFs. Case 3 (SODA EOFs over 1958–2001) provides a reconstruction trend map over 1950–2003 that differs significantly from the previous two cases. We discuss possible causes for such differences. For the three cases, on the other hand, reconstructed spatial trends over 1993–2003 agree well with the regional sea level trends observed by Topex/Poseidon.”
Sea level is clearly not decreasing since 2003, as you can see at the following link:
http://www.cmar.csiro.au/sealevel/sl_hist_last_15.html
From the graph at the above site, it’s apparent that sea level fell a bit during the 2007 La Nina, but it’s clearly on rise again. The trend is 3.3 mm/year, about double the 20th century trend and clearly an acceleration over the past 50 years.