Monday, December 15, 2014

Bob Tisdale is in a tizz over record hot seas


Update - I've added a bit on trends and anomalies, highlighting Bob's deception - just in case a stray arrives from WUWT. Sou 15 Dec 14.


Bob Tisdale has got himself into a real tizz over the record hot seas. He's posted several articles about how the seas are only getting hotter because they are getting hotter. Six just in the last week at WUWT, would you believe! It's not that they are getting hotter from global warming. They just happen to be getting hotter. Bob seems to think it's got nothing to do with global warming. It's just warming.

Bob's article had the rather long title: "The Nonsensical “Just What AGW predicts” and Other Claims By Alarmists about “Record-High” Global Sea Surface Temperatures in 2014"

Be warned - this article is a bit long-ish. While it's too, too easy to ridicule Bob's stupid greenhouse effect denial, that's not what made this article long. What happened was that I got sidetracked down various other sea surface temperature pathways.


It's not greenhouse gases, it's magic...


Bob doesn't deny the fact that the sea surfaces are getting hotter and hotter. He doesn't deny that they've never been this hot ever before in the instrumental era. What is getting him so worked up is that he is worried that people might think it's a sign of global warming. Worse still, they might think global warming is being caused by greenhouse gases. Worse still, someone at WUWT might think the warming might be the end result of all the extra greenhouse gases we've thrown up in the planet-wide rubbish dump in the sky.

Someone had the cheek to write a comment in one of Bob's previous articles that got Bob all hot and bothered (and no doubt didn't add anything to global warming, only to Bob's personal warming). He wrote:
A well-known alarmist chose to leave a comment on my blog here, in which he stated:
 Global SSTs at record highs… Just what AGW predicts.
I not only responded to that comment on that thread...
There was nothing wrong with the snippet he quoted, so I went to his previous article to see what all the fuss was about. It was curious for two reasons. First of all it showed that occasionally a "warmist" will visit Bob Tisdale's own personal blog. Hard to credit but there you go. In this case it was David Appell, who has an alarming blog - he writes about climate! Secondly, Bob didn't like the comment but he wasn't able to dispute it. What he did instead was write something about climate models not mimicking all the variations in surface temperature at precisely the time they vary. That's not how Bob wrote it. What he wrote was:
December 13, 2014 at 3:50 am
David Appell, you’re wrong once again. First off, I let your comment through this time, even though I banned you for wasting my time a while back…and still you insist on wasting my time.
Second, climate models don’t simulate Earth’s oceans. They simulate some planet’s oceans, but they’re not Earth’s. Even with the warm sea surface temperatures this year, the models still double the warming rate of global ocean surfaces over the past 33 years:
...and proceeded to put up a a couple of charts of sea surface temperature, including this one:

Source: Bob Tisdale (in case you couldn't tell!)

You can click on the chart to enlarge it. One of the first things you'll notice is that Bob modeled monthly data, where over shortish periods it's much harder to see the long term trend. Another thing you'll notice is that the chart has this written up the top:
Data and model outputs shifted so trend lines zero at start of time series.

I've no idea why Bob thinks it necessary to have the trend lines zero at the start. What he should have done was align the charts to the same baseline anomaly, not to a zero point trend line. Then he might have got something that looked like this - if he'd used different observational data:

Data sources: KNMI Climate Explorer and Hadley Centre

For the period he chose - or close enough - the trends are as follows for the data I used:
  • HadSST v.3.1.1.0 the trend is 0.132 a decade.
  • CMIP5 tos RCP6.0 the trend is 0.166 a decade.

So the CMIP 5 trend is certainly higher, but nothing like the difference that Bob got, where he said that the observed trend was only 0.87 a decade. He said he took tos for the CMIP5 data, which I did too. I chose the CMIP5 mean for tos at RCP6.0 from KNMI Climate Explorer - which I think is the same data as Bob Tisdale chose. However the above chart shows HadSST instead of Bob's choice, which was Reynolds' OI SST v2.

Another thing you'll notice is that the Hadley Centre's sea surface temperature is now approaching the modeled temperature. That's a tad surprising given the models of the time didn't allow for the lower solar irradiance, low level volcanic activity or aerosols over the past few years.


Difference in observations of sea surface temperature


The main reason for the difference between the chart above of HadSST and CMIP5 and Bob Tisdale's chart is the data he used for observations. Bob used the NOAA data - Reynolds Optimum Interpolation Sea Surface Temperature Analysis or Reynolds' OI SST v2, which is described here

I've plotted that data, together with HadSSTv3.1.1.0 and with ERSST (used by NASA). I've aligned them all to a 30 year baseline from 1982 to 2011. 1982 was the first full year I could get in the Reynolds' data from Climate Explorer. All the data was from KNMI Climate Explorer except for HadSST, which came from the Hadley Centre. I've also extended the CMIP5 data out to 2018 - just to show the variation over time. It may make watching the deniers interesting over the next two years, because the CMIP5 mean tapers off a little. If sea surface temperature keeps going up the way it has been lately, it will rise above the model mean sooner rather than later.


One thing you'll probably notice is that although all follow similar patterns over time, the Reynolds and ERSST are pretty close to each other whereas HadSST starts off cooler and ends up warmer.


Different baselines


Another thing is that choosing a different baseline period for the data makes a difference when doing comparisons. In the above chart, HadSST is almost touching CMIP5. The difference between the anomalies for the two are shown below:

1982-2011 baseline less the 1961-1990 baseline:
  • HadSST = 0.215°C; 
  • CMIP5 = 0.231°C
  • Difference = 0.016°C 

The reason is the way I adjusted the anomalies, which was simple and probably not the most accurate. What I was aiming for was to use the same baseline average for each one over time.

For each data set I worked out the average anomaly for each year. I took the average of the annual anomaly/temperature over the 30 year period as the zero line. Then I deducted the annual average temperature from the baseline average for each year. The difference between one average 30 year period and another can be different for different data sets.

If you can't follow that just ask. If you can tell me how to improve the calculation (without having to average each month separately), please do so.


Why did Bob Tisdale use Reynolds' OI SST v2?


Another interesting thing you'll have noticed is the trend for Reynolds' is the lowest of the lot. Is that pure coincidence or is that why Bob Tisdale chose it? I'll leave that to you to speculate. Here are the trends - note the different period for CMIP5, which lowers the trend a tad (compared to the chart above):
  • HadSST = 0.132°C/decade (1982-2014).
  • Reynolds = 0.088°C/decade (1982-2014).
  • ERSST = 0.098°C/decade (1982-2014).
  • CMIP5= 0.161°C/decade (1982-2018)

Update: Trend vs anomaly


I may not have made it sufficiently clear. For the period that Bob focused on - 1982 to now, not only did he pick the data with the least trend, but he shoved the CMIP5 model mean for sea surface temperature way up higher above the Reynolds data. He didn't align the charts properly. So he made it look as if there was a much bigger difference between the model mean and observations than there actually is. The way he did this was by aligning the bottom of the trend lines rather than aligning the charts themselves on a common baseline of the same thirty year average. Because the trend line for the CMIP5 mean is steeper, that meant he had to shove it way up higher on the chart and move the observations down lower. So his curves on that chart are in no way comparable.

I know I said that already, and the chart comparisons show what he did. Still, I thought I'd better mention it again just in case anyone missed it. It's easy to get distracted by short-ish trends and lose sight of the fact that the seas are heating up in absolute terms. And any recent gap between the model mean and the observations is closing fast. There have been gaps before. Give me a second and I'll put up a longer term chart so you can see what I mean. Bear in mind the poor coverage prior to 1970, so uncertainty will be higher way back when. Anyway - here it is - click to enlarge as always:

Data sources: KNMI Climate Explorer and Hadley Centre


I'm wondering if Bob Tisdale even knows what temperature anomalies are, given what he's done. Or if he does know. In other words was he trying to fool his readers or is he just plain ignorant?

[Added by Sou 15 December 2014 01:16 pm AEDT]

Sources of data


Why the difference in sea surface temperatures, you may be asking, so I did some investigation. Here is what I found out.

Reynolds' OISST

This is the description of what is referred to as the Reynolds' data or the NOAA Optimum Interpolation (OI) Sea Surface Temperature (SST) V2. It has a grid of 1.0 degree latitude x 1.0 degree longitude global grid (180x360) and covers virtually all the globe, from 89.5N - 89.5S, 0.5E - 359.5E. It doesn't say where the data come from except for mentioning satallite data (see below for more info). 
The analysis uses in situ and satellite SST's plus SST's simulated by sea-ice cover....The OI analysis is done over all ocean areas and the Great Lakes. There is no analysis over land. The land values are filled by a Cressman interpolation to produce a complete grid for possible interpolation to other grids. The ocean and land areas are defined by a land sea mask (the lsmask.nc file). Land values for sst do not necessarily coincide with land values from ice analysis.
There is a paper discussing these data and correction made to version 1, which resulted in version 2.  It's gives a lot of insight into how sea surface temperatures are worked out and where the data come from. Here are some excerpts, explaining the difficulties with satellite and other data and the inconsistencies with other data sets:
The in situ SST data are determined from observations from ships and buoys (both moored and drifting). Most ship observations in our period of interest were made from insulated buckets, hull contact sensors, and engine intakes at depths of one to several meters. ...
...In late 1981, Advanced Very High Resolution Radiometer (AVHRR) satellite retrievals improved the data coverage over that of in situ observations alone. The satellite retrievals allowed better resolution of smallscale features such as Gulf Stream eddies. Because the AVHRR cannot see the surface in cloud-covered regions, the biggest challenge in retrieving SST is to eliminate cloud contamination. The cloud-clearing algorithms are different during the day and the night because the AVHRR visible channels are useful in detecting clouds but can only be used during the day. Once clouds have been eliminated, the SST retrieval algorithm is designed to minimize the effects of atmospheric water vapor. The algorithms are ‘‘tuned’’ by regression against quality-controlled buoy data using the multichannel SST technique of McClain et al. (1985)...
Tuned algorithms - I bet that was what got Bob so enamoured. It wasn't the fact that it showed the lowest trend for the period after all. It was tuned algorithms that won him over :)

ERSST

Here is the NOAA description of ERSST.  ERSST is used by NASA's GISS in it's land-ocean surface temperature record, GISTemp. It is also used by NCDC/NOAA for its global surface temperature anomalies. It has a coarser grid of 2.0 degree latitude x 2.0 degree longitude global grid (89x180). It covers almost the same amount as the OISST, from 88.0N - 88.0S, 0.0E - 358.0E.
The extended reconstructed sea surface temperature (ERSST) was constructed using the most recently available International Comprehensive Ocean-Atmosphere Data Set (ICOADS) SST data and improved statistical methods that allow stable reconstruction using sparse data. This monthly analysis begins January 1854, but because of sparse data the analyzed signal is heavily damped before 1880. Afterwards the strength of the signal is more consistent over time. 

HadSST

And here is how HadSSTv3.1.1.0 is described at the Hadley Centre website. It has the coarsest grid of the three, being 5° latitude by 5° longitude grid. It uses the same data from ICOADS as does ERSST, up until 2006. After that it uses GTS (Global Telecommunication System) observations. (GTS data is transmitted from buoys and ships as far as I can make out.)
The SST data are taken from version 2.5 of the International Comprehensive Ocean-Atmosphere Data Set, ICOADS (external web page), from 1850 to 2006 and on GTS observations from 2007 onwards. HadSST3 is produced (a slightly more detailed description) by taking in-situ measurements of SST from ships and buoys, rejecting measurements that fail quality checks, converting the measurements to anomalies by subtracting climatological values from the measurements, and calculating a robust average of the resulting anomalies on a 5° by 5° degree monthly grid. After gridding the anomalies, bias adjustments are applied to reduce the effects of spurious trends caused by changes in SST measuring practices. The uncertainties due to under-sampling and measurement error have been calculated for the gridded monthly data as have the uncertainties on the bias adjustments following the procedures described in the paper.
For a detailed description of the dataset and its production process, please read the papers (part 1 and part 2) describing the data set. We recommended you read both papers before using the data.

ICOADS

ICOADS is the International Comprehensive Ocean-Atmosphere Data Set. It:
...offers surface marine data spanning the past three centuries, and simple gridded monthly summary products for 2° latitude x 2° longitude boxes back to 1800 (and 1°x1° boxes since 1960)—these data and products are freely distributed worldwide. As it contains observations from many different observing systems encompassing the evolution of measurement technology over hundreds of years, ICOADS is probably the most complete and heterogeneous collection of surface marine data in existence. 

The ICOADS page has some interesting information, such as where the measurements come from - over time. They list ships, moored buoys, drifting buoys and C-MAN (Coastal-Marine Automated Network stations ). And the chart below shows how much of the ocean has been sampled over time and for what. The area sampled grew hugely between 1940 and 1970:

Figure 3. Percentage global ocean and coastal area (1800-2007) sampled in Release 2.5 based on area-weighted 2° boxes (smoothed) for sea surface temperature (S), requiring at least five observations per month in each box, and determined from the "enhanced" (4.5σ trimming) product that includes ship and buoy records. Other curves compare the S coverage, at five observations per month, with that for sea level pressure (P), air temperature (A), wind speed (W), total cloudiness (C), and relative humidity (R). Also plotted is the evaporation parameter (G), which is computed from S, P, A, W, and R, and thus illustrates the extent to which surface fluxes can be computed from the individual observations. Source: NOAA

I didn't expect to wander around so much in this article. It was interesting to me to see that there are differences between the data sets, even though some of them overlap in regard to sources (eg ICOADS).


Models vs observations


In the comments a few days back, Harry Twinotter remarked that deniers have changed the messaging and are redefining the meaning of "pause". They are no longer claiming "it's not warming" - well the main disinformers have stopped saying that.  Many of them have stopped talking about a "pause" altogether, (leaving aside Christopher Monckton, and he doesn't go beyond the RSS satellite lower troposphere data). With the record global temperatures of the past few months, disinformers have shifted to "it's not warming as much as the models".

I wonder how long they'll be able to keep that one up for? They'll certainly have a hard time if more model runs come out with the correct forcing for solar and volcanic activity and aerosols.


Haunted by the heat!


Bob likes to make sure nobody misses the points he is making, even when they are plain dumb. He wrote:
THE WARMING IN THE NORTH PACIFIC IS NOT THE “MISSING HEAT” COMING BACK TO HAUNT US
We’ve already seen comments around the blogosphere to the effect of “high sea surface temperatures in the North Pacific indicate the increase in ocean heat is coming back to haunt us”.
He doesn't say where he saw those comments. I can't say I have but then I could have missed it. Bob explains what he wants you to believe:
That nonsense is contradicted by data. We only have reasonably complete and reasonably realistic measurements of subsurface ocean temperatures for the past decade or so, all thanks to the ARGO program. The vertically averaged subsurface temperature data from the NODC, Figure 2, for the extratropical North Pacific (20N-65N, 100E-90W), for the depths of 0-700 meters and 0-2000 meters, both show a negative trend, and that means the extratropical North Pacific from the surface to depths of about 1.25 miles have cooled slightly, not warmed, since the ARGO floats have been in place.

What he seems to be saying is that the seas haven't warmed from the bottom up all in the same spot. He trips around various oceans and touches on different papers and finally pounces on Durack14 (which I wrote about here), which had this as the first sentence in the abstract:
The global ocean stores more than 90% of the heat associated with observed greenhouse-gas-attributed global warming.

Ooh! Bob really didn't like the mention of greenhouse gases. He's a greenhouse effect denier from way back. He wrote:
The statement “observed greenhouse‐gas‐attributed global warming” is nothing more than a clever regurgitation of climate science fallacy. Warming of the oceans to depth has been observed, but climate models are used to attribute the warming to greenhouse gases.  

It's physics, not models


Of course Bob's got it back to front and upside down. There is no fallacy - there is physics. Warming has been observed but it's physics that attributes the warming to the greenhouse effect, not climate models. The same physics is the basis of climate models. Physics drives the models not the other way around. And the physics is based on observations. It's not pie in the sky stuff. Bob's a plain vanilla denier who thinks "scientists don't know nuffin'". Every time he puts his fingers to the keyboard he demonstrates the Dunning-Kruger effect.


From the WUWT comments


Lil Fella from OZ
December 14, 2014 at 2:23 am
As usual AGW alarmists are dreaming!

Mike H. (not the one we know, unless he's Poe-ing)
December 14, 2014 at 2:57 am
You’re correct we did get UKIP and very well they did too in the elections for MEP’s. Sadly their message on useless wind and solar energy projects is lost in the noise made by the media (The BBC mainly) about their policies on immigration. UKIP need to start banging the drum about the AGW scam a lot louder. 

Brute  has noticed how WUWT has banned almost every normal person from his blog:
December 14, 2014 at 2:48 am
There are fewer and fewer vociferous warmists every year.

mairon62  doesn't read science:
December 14, 2014 at 2:49 am
When will the alarmists show some respect for their own learning-curve? They cling to their silly mono-variable (co2) explanations to describe a complex world that involves multiple variables interacting in dynamic and perhaps chaotic relationships. It reminds me of Wiley Coyote’s “95% confidence” as he madly saws through the tree branch he’s standing on, only to discover that he’s standing on the wrong side of his cut when he’s in FREE FALL. How can we learn from our mistakes if we can never admit that we make them? “Look out below!” to all the arrogant, name-calling, pseudo-scientists who have made the learning process their enemy. Thanks to Bob for yet another informative post and a great example of what to do with new information.

KNR makes some grand statements out of ignorance and only toward the end thinks to "hear" the question:
December 14, 2014 at 3:01 am
Next year should there be no ‘record ‘ the alarmist can revert back to ‘one year means nothing ‘ , the heads you lose tails you I win approch, although scientifically worthless, sure does make life a lot easier for those that wish to be be always ‘right’ no matter what the reality.
Meanwhile the problem remains that the amount of data with have on ocean temperatures is tiny compared to the vast range of the ocean , so once again we revert to claiming that one star can tell us about all the billions of others stars ‘because ‘
Hear is a question, in an ideal world how many actual valid measurements of temperature would be required both land and sea to produce an actually average temperature that has real honest value , and how many do we actual have compared to that ? 

Does this paper help answer KNR's question - maybe coupled with this?

Source: Argo UCSC

Oh, a WUWT thread about hotter seas wouldn't be complete without speculation about undersea volcanoes (somehow managing to skip warming the lower ocean and jump straight to heating the top). This time it's Gerry, England
December 14, 2014 at 4:04 am
The oceans are the difficult bit since they cover 7/8 of the planet and yet how many measuring points are there? But I would suggest that even if it were possible to create a reliable network, you would need to know what is going on below the surface at the ocean floor to put your readings in context. If an area sees warming, could it be from subsea volcanic action? Note that the melting of the antarctic peninsula ice has been attributed to warm water below not warm air above and that the heat source is volcanic.


I knew it wouldn't take long before I could refer to Frank D's volcanic calculations :)

The mods must have been napping because Rob Painting wrote - and it's still there:
December 14, 2014 at 3:36 am
The multi-model mean eliminates natural variability, so of course the multi-model mean doesn’t match the recent period dominated by the negative phase of the Interdecadal Pacific Oscillation (IPO) – the largest source of natural variability in the climate system over multi-decadal timeframes. It’s a strawman argument to make such a comparison.
The record sea surface temperatures are suggestive of the IPO moving into its warm (positive) phase. The weaker winds mean the export of warm surface water out of the tropics is slowing down, and the mixing of heat down into the subtropical gyres is weakening. The outcome of all the changes in ocean circulation should see sea surface temperatures increasing dramatically over the coming years. The sluggish transport of warm surface water out of the tropics will be very problematic for coal reefs. We will see a swarm of bleaching events during the positive phase of the IPO.

I noticed in the press there is a lot of concern at the moment about coral bleaching - also see the video here.

Rob Painting explains more about climate models, which deniers like Bob Tisdale will never 'get" - though I know he'd have read the same here and elsewhere.
December 14, 2014 at 4:10 am
It’s really not that difficult to understand. Run a whole bunch of model simulations and natural variability occurs at different times because the models are individual possible realisations of Earth’s climate. Average them all together, which is what the multi-model mean is, and you remove all the wiggles representing these natural climate variations from the individual simulations.

Bob Tisdale isn't shy about showing off his ignorance, nor does he probably realise he's substantiating what Rob Painting wrote:
December 14, 2014 at 7:50 am (excerpts)
...Rob, I presented model-data comparisons starting in 1981. Are you aware the IPO was positive for most of that time. But that’s neither here nor there.

Yes, Bob - right up until the sea surface temperature drifted below that which was modeled. He continues:
Second, you’re wrong about the IPO about being the largest source of natural variability over any timeframe. ENSO dominates the Pacific and the globe. Are you aware there are multidecadal variations in the strength, frequency and duration of El Niño and La Niña events, so that El Niños dominate during some periods and La Niñas in others? It’s easy to see when you smooth HADISST-based NINO3.4 SST anomalies with a 121-month filter.
Bob's misquoting - Rob wrote over "multi-decadal time frames" not *any* time frame. Bob knows very little about anything except ENSO and how to plot sea surface temperature charts.  Surprisingly he doesn't know anything much about the PDO. (I noticed this when he wrote an article recently without mentioning the PDO once, when he should have.) When Bob talks of "multidecadal variations" in ENSO - they demonstrate the impact of the PDO, with El Nino's not being as strong when the PDO is in its cool phase, while La Nina's can dominate. For example, from NASA (my emphasis):
The PDO can intensify the impacts of La Niña or diminish the impacts of El Niño. In its "cool, negative phase," warm water, which causes higher-than-normal sea-surface heights (because warmer water expands and takes up more space), forms a horseshoe pattern that connects the north, west and south Pacific with cool water in the middle. In its "warm, positive phase," these warm and cool regions are reversed, and warm water forms in the middle of the horseshoe.
Such phase shifts of the PDO result in widespread changes in Pacific Ocean temperatures and have significant global climate implications. During the 1950s and 1960s, the PDO was strongly negative, or cool, and global temperatures seemed to level off. During most of the 1980s, 1990s and 2000s, the Pacific was locked in a strong positive, or warm, PDO phase and there were many El Niños. We are currently in the early stages of a cool PDO phase that began around 2006. Cool, negative phases tend to dampen the effects of El Niños.

whiten wrote a very long comment trying to back up Bob's argument that global warming doesn't mean greenhouse warming - it could be something else that's causing it, but whiten doesn't say what that might be. Not even a guess. I haven't pasted the lot, but you get the drift. Anything but CO2, though "anything" isn't specified.
December 14, 2014 at 4:55 am (extract)
The bigger problem with the AGW mentality is that it confuses the GW (what we call global warming) with AGW.
In that mentality Gw is by default an AGW.
While NO ONE REALLY CONTENDS OR DISPUTES THE ~0.8C warming of the last ~150 years(actually what we call a GW) they keep claiming and interpreting any sign or effect of it as a certain AGW.
As far as I can tell, the problem of the oceans heat content in the past, previous to the hiatus, has actually been ignored by the AGW croud simply because it’s patern of variation did confuse the AGW.
The signal in that variation does not seem to have lagged behind and following the atmospheric warming as it should have been expected in the case of a GW caused by CO2 emissions or in the case of an AGW.
It’s pattern actually makes the oceans heat content to be considered more significant as a probable cause of the GW of the last 150 years. It seems like the GW has followed the oceans warming pattern actually, especially in the first part of the warming period.
Is ridiculous to think, claim and pretend that the 0.8C warming will not show any signs in the pattern of the oceans heat or warming.
Is even more ridiculous under the cicumstances to blindly and without any care at all consider the latest observed warming of oceans surface as a clear sign of AGW.

Luke tries to tell Bob that the oceans can't keep warming forever without some forcing agent. Blaming it on "weather" won't wash:
December 14, 2014 at 7:17 am
Bob, your concluding statement is nonsensical. You state “For nearly six years, we’ve discussed how weather events can lead to long-term warming of the oceans—at the surface and at depth.” If the coupled atmosphere/ocean system is not gaining heat, how can you have long-term warming of the oceans without a large decline in atmospheric temperatures? The answer, of course, is that the overall heat content is increasing tremendously- the latest estimate is about 250 trillion Joules per second.

Bob Tisdale is either thick as two planks or being disingenuous - I opt for the former. Feel free to pick the latter. Bob ignored the bit about the "coupled atmosphere/ocean system", which is the point that Luke was making. In other words, if there wasn't greenhouse warming then the overall system wouldn't be getting hotter. If the system is being forced then it can't just be "weather".
December 14, 2014 at 8:12 am
Luke, my statement is not nonsensical. I did not say the coupled atmosphere/ocean system is not gaining heat. Read what I wrote. It’s real easy to understand. Here it is again:
For nearly six years, we’ve discussed how weather events can lead to long-term warming of the oceans—at the surface and at depth.
You even quoted it, so I’m really surprised you misunderstood it. Then again, you may have been trying to misrepresent what I wrote. Now, that would not surprise me.
Have good day, Luke. 


Paul J. Durack, Peter J. Gleckler, Felix W. Landerer and Karl E. Taylor "Quantifying Underestimates of Long-term Upper-Ocean Warming." Nature Climate Change 5th October 2014. DOI: 10.1038/nclimate2389 (pdf here)

Reynolds, Richard W., Nick A. Rayner, Thomas M. Smith, Diane C. Stokes, and Wanqiu Wang. "An improved in situ and satellite SST analysis for climate." Journal of climate 15, no. 13 (2002): 1609-1625. doi: http://dx.doi.org/10.1175/1520-0442(2002)015<1609:AIISAS>2.0.CO;2 (open access)

41 comments:

  1. It's interesting that only the Reynolds OISST data incorporates satellite observations and that it exhibits the lowest trend.

    Satellite SST data remain problematic to this day:

    The mean [ocean] skin temperature is generally several tenths of a degree colder than the mean bulk temperature (Schluessel et al., 1990).The instantaneous bulk-skin temperature differences can be as large as 1.0 K to -1.0 K (Robinson, 1985), depending on the wind and surface flux conditions.For instance, when the long wave radiation from the upper few micrometers of the ocean is upward, the skin temperature is usually cooler than the bulk SST.Latent and sensible heat fluxes can cool the sea surface further if the air is dryer or colder.

    Because of the small penetration depths of the infrared and microwave radiation, the satellite instruments from space can only measure the upwelling long wave or microwave radiations from the surface skin layer. However, most oceanographers are interested in the bulk SST in the surface mixed layer because traditionally this is the temperature measured by ships, by drifter buoys, and by moored thermometers, etc., and because the variations of the bulk SST involve large heat exchange, which can impact the earth´s climate.The errors of satellite SST measurements due to the bulk-skin temperature difference can cause significant inaccuracies in global climate studies.



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    1. BBD yes, I hadn't realised the extent of the problems till I read the Reynold's paper.

      I think HadISST infills with satellite data for its 1x1 grid. It probably has the advantage of HadSST to keep it more on the straight and narrow.

      BTW - makes you wonder why Bob chose the Reynold's data, given he pretends to be so finicky about accuracy - and even the authors seem to be saying it's the worst of the bunch. Bob's doing a Monckton :D

      Delete
  2. That's a damn fine laptop you've got Sou.

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  3. That last exchange with Luke proves Bob is both dense and disingenuous. First, because he's too dumb to understand the law of energy conservation. Thus, he thinks things can warm by magic. Second he's disingenuous because he notices that he has sidestepped the coupled system question, and then continues to sidestep it. An honest person would say, "however, if you're wondering if the combined system is gaining heat and, if so, what's causing it, well...it is gaining heat and it is AGW." OK, ok, I don't expect him to answer the question correctly, but he could at least acknowledge and address the implicit questions if he were a true and curious skeptic.

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    Replies
    1. The coupled system mechanism is obviously friction.

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    2. Ha! Of course, you break a system into two parts. Those two parts have friction and now you have your source of energy!

      Delete
    3. Call it Bob's perpetual motion climate machine.

      Delete
  4. I look forward to next reading Mr. Tisdale's striking new theory on dinosaur physiology: ""All Apatosauruses are thin at one end, much, much thicker in the middle, and then thin again at the far end."

    With due credit to the vertebrate paleontologists of Monty Python.

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  5. Since you mentioned the seas, I'll call this on-topic: maps of various cities with extreme sea level rise (I'll link to my own fair city -- my apartment will be dry land).

    http://spatialities.com/2014/12/02/montreal-archipelago/

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  6. Gerry, England (undersea volcanoes): "The oceans are the difficult bit since they cover 7/8 of the planet"

    Sorry for being such a scientist: it is 2/3.

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    Replies
    1. He's just a man ahead of his time :)

      via numerobis: http://spatialities.com/2014/12/02/montreal-archipelago/

      Delete
    2. Or, using Tisdale logic, the oceans cover the wet bits.

      Delete
  7. Re the Mike H. comment.
    http://www.heraldscotland.com/politics/political-news/revealed-the-hate-filled-face-of-ukip-in-scotland.20948587

    Probably time for me to get a new online id.

    ReplyDelete
    Replies
    1. Oh no - don't do that. (The other Mike - the denier - usually posts as the Scottish Sceptic at WUWT.)

      Delete
  8. Sou,

    Thanks for the more complete analysis linked to, you know, actual theory ... and plain common sense.

    I probably haven't fully absorbed your anomaly calculations to know if this would make a material difference, but when dealing with CMIP5 data I always make sure the models are pegged to observations via a 1986-2005 baseline first before moving the whole mess to some other baseline, say 1951-1980 to match GISS. Reason being, it's my understanding the 1985-2005 baseline is chosen because 2006 is the beginning of the projected (vs. hindcasted) portions of the model runs, so the 20-year baseline ending at that boundary gives the truest indication of performance to actuals.

    ReplyDelete
    Replies
    1. Yes, what I did was a bit rough - but fundamentally sound.

      What Bob did was quite silly (I'm being kind) - shifting the charts to make both trend lines start at zero.

      You can see in the second chart of mine, with the trend lines for all of them, that he'd have to have shoved the model mean curve up quite a bit higher to get the trend line to start in the same spot as the Reynolds (or any of them). Double deception.

      Delete
    2. Sou, to my eyeballs, your calcs look just fine as the hindcasted model portion runs right through the middle of the actuals curves. Bob looks to be pulling another Spencer-esque "95% of observations are wrong" manuver. I thought about doing my own graph and calling him on it, but didn't have the energy to waste my time wasting his time.

      Delete
    3. ... which is my long-winded way of saying thanks for taking the time to do a bang up job of rebutting his nonsense. :)

      Delete
  9. I've added an update to make the point clearer, in case anyone missed out on his double deception. Including a chart of all the instrumental data available.

    ReplyDelete
  10. "What Bob did was quite silly (I'm being kind) - shifting the charts to make both trend lines start at zero. "

    He might be a poster child for Dunning Kruger, but he's learned from the master with that half witted trick. That's straight out of Monckton's playbook.

    ReplyDelete
  11. I know you're reading Bob Tisdale. I challenge you to explain--using fewer than 250 of your own words--how your "persistent weather event" creates higher sea surface temperatures.

    ReplyDelete
    Replies
    1. "Persistent weather event" is a euphemism for "climate". Bob is really a closet warmist. You heard it here first.

      Delete
  12. This paper is going to not help then ...

    http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-14-00006.1.

    Shows that in the new ERSSTv4 the warming in most recent decades is enhanced. Two things the buoy correction and the infilling technique change things in last 20 years.

    Part 2 is also somewhere in the AOP queue there and adds uncertainties. No, I don't want my mental imagery to go there ...

    ReplyDelete
    Replies
    1. Well guess what?

      Bobby or another WTFUWT? is lurking over this thread.

      How do I know this?

      WTFUWT? has a new (~2 hour old) thread (by BT) on the above paper mentioned here, like more than 12 hours ago.

      And the 1st Google reference is?

      Oct 14, 2014, like two whole months ago, way to go BT, getting his science from HW!

      Delete
    2. Yes, Bob is a avid reader of HW (though often the HW articles go over his head).

      I see that he's now decided to align his SST curves to a baseline period, too. I wonder how long that will last?

      Delete
    3. Maybe we can educate him by the back door then? If we keep posting links to science and all.

      Delete
  13. A general plea. Would everybody please stop wasting Bob Tisdale's time.

    ReplyDelete
  14. "Bob"'s been caught shifting trend lines upwards before:

    http://tamino.wordpress.com/2011/05/09/favorite-denier-tricks-or-how-to-hide-the-incline/

    He hasn't got a clue. Not a statistical bone in his body. He's good at writing lots of nonsense that tops the 5000 word mark though. I think most LOL, WHUT!ers make it through the first para or so and then chime in with a "Great job, 'Bob'!", then move on to consume the next bit of nonsense over there.

    ReplyDelete
  15. It may be amusing to snark at Dr Bob, but the issue is one of epistemic closure rather than a Dunning-Kruger effect.

    Some time ago at WUWT when Bob was explaining how the 'so called AGW' warming trend was really just the ENSO cycle acting as a ratchet, with warming during El Nino dominated periods and stasis during La Nina periods, I complimented him on his accurate description of the instrumental data.

    But pointed out that this staircase pattern of warming he had described was not present in the last 1000 years of ENSO data, that showed a sawtooth pattern around a steady average.
    As it was generally agreed that during El Nino periods the Earth lost energy because of a positive energy imbalance, and gained energy during La Nina periods the fluctuation around a mean was expected.
    What required an explanation was the recent change in description of ENSO temperatures that showed no cooling after El Nino periods.
    I suggested that the small changes in the way energy was lost from the Earth might result in less energy lost and more gained in each part of the cycle, so that the sawtooth of past ENSO cycles is converted to the ratchet/staircase of the present.
    And perhaps the findings about the physics of radiative transfer of CO2 would help provide part of the missing explanation for the reason for the change in ENSO behaviour.

    This was met with more blank incomprehension than hostility. What was obvious was that for Bob, the description was sufficient. It answered all questions about what was happening, and any further analysis was viewed as partisan quibbling. The necessity for any further explanation of events was dismissed. His accurate description closed the matter definitively.

    I did point out that this made the situation even more alarming than the AGW theory. After all if ENSO now works as a ratchet on global temperatures, then when will it stop? before or after the Oceans boil dry ?!
    (Grin)

    izen

    ReplyDelete
    Replies
    1. Epistemic closure, I like that. I've found the best reason to bring up the concept of the planet dissipating more energy during positive ENSO phases than negative in contrarian fora is as fodder for their own raucous amusement.

      Delete
  16. where he said that the observed trend was only 0.87 a decade

    Bob's hiding the incline again? Tsk tsk.

    ReplyDelete
  17. A few general bits as I know Dick Reynolds professionally. (Aside: He has finally finished retiring.)

    One is, the 1 degree weekly OI is not his latest/greatest analysis system. It is a legacy system, run only for the use of the CPC (climate prediction center).

    For a decade or more, he (and collaborators, now Viva Banzon and collaborators) have done a 0.25 degree, daily analysis (still using OI methods), with retrospective run back to September, 1981 -- when the AVHRR was first launched. See http://www.ncdc.noaa.gov/sst/ for data.

    The satellite versus buoy problems/issues do exist, as to buoy vs. ship, and argo, and ... well, observing is a messy problem. But the quote makes it sound worse than it is. We _can_ have diurnal layers form -- very warm, very thin layers of water. But to do this requires that it be sunny (never happens at night, or morning), clear, and calm (winds less than 6 m/s required, less than 2 m/s to get a strong layer). Most of the day, and almost all of the globe, these conditions don't exist.

    The satellite observations are indeed, strictly speaking, of the skin temperatures. But they are referenced (not exactly adjusted) to buoy temperatures. This part is actually, because of the scarcity and infrequency of diurnal layers, not too much of a problem. The part that is more problematic is using statistical regressions between the satellite observations (energies observed in different infrared bands) and sea surface temperature in the first place.

    A different approach, which avoids that regression problem (but not the skin vs. buoy temperature issue) is to do what's called a physical retrieval. Take your knowledge of radiative transfer and the current state of the atmosphere (by way of a global weather analysis) and trace the satellite's band observations back to what surface temperature would cause them. The results are generally pretty close to the statistical regressions (which is why some people still use them), but tend to be markedly better in very humid or very dry conditions (tropics and poles, for instance). One such source for current (as opposed to climate) SST analysis is http://polar.ncep.noaa.gov/sst/rtg_sst_high/

    (if you recognize a name, rest assured that all comments here are mine alone and do not represent my employer.)

    ReplyDelete
    Replies
    1. Thanks Robert. I wasn't able to work out who used the data so you've filled in some gaps. I didn't mean to sound disparaging of the work, either - only of Bob Tisdale's misuse of it. I found the paper I referenced extremely informative, too, even though it's a few years old now.

      Delete
    2. No problems, just that this was a rare chance for me to add some behind the scenes comments.

      The bulk of sst analysis hasn't changed fundamentally for a couple of decades, so you don't need to be too concerned about the age of the papers. Some details have, such as the physical retrievals (only used in the last about 10 years), and the increased interest in diurnal layers in the last ~5-10 years.

      If (when) you have questions, feel free to send me email, or a twitter dm.

      Delete
  18. Has anybody read the exchange with Nate in https://archive.today/4wwIC#selection-1191.54-1191.288 ? Too funny. Here's some of my favorite quotes:
    "The higher sea surface temperatures in 2014 are easily explained by the upward shifts in the sea surface temperatures, of the South Atlantic, Indian, and West Pacific Oceans, in response to the 1997/98 El Nino and the 2009/10 El Nino…."
    (emphasis mine because that text kept me laughing and wanted to share the fun)
    Later Nate asks:
    "discussion about the upward steps after El Ninos/La Ninas. Would expect downward steps or gradual downward decays as well, but don’t see these. How do you understand this? AGW?"

    Bob replies:
    "Nate, there are gradual decays in the sea surface temperatures, but the next strong El Nino came before the decay was complete."
    then
    "Downward steps? We only have 33 years of satellite-enhanced SST data. If and when we see one, I’ll be the first to report on it. "

    Bob is so close, yet so far.

    ReplyDelete
    Replies
    1. Bob is such a sad fake, but he gets no sympathy because his tone is constantly humorlessly pseudo-authoritative. It's a grating performance.

      He must be very disappointed with the La Nina dominated decade undermining him :)

      Delete

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