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Discussion > Questions for the UKMO

More adjustments noted recently:

"There has been much discussion recently about temperature adjustments made by GHCN in Iceland and Greenland, which have had the effect of reducing historic temperature levels, thereby creating an artificial warming trend. These can easily be checked at the GISS website, where both the old and new datasets can be viewed as graph and table data, here and here.

It has now been identified that similar adjustments have been made at nearly every station close to the Arctic Circle, between Greenland and, going East,via Norway to Siberia, i.e 56 Degrees West to 86 Degrees East, about 40% of the circumference.
...
Trausti Jonsson, a senior climatologist at the Iceland Met Office, has already confirmed that he sees no reason for the adjustments in Iceland and that they themselves have already made any adjustments necessary due to station moves etc before sending the data onto GHCN.

Clearly the fact that nearly every station in the region has been adjusted disproves the idea that these sites are outliers, which give biased results not supported by nearby stations.

GHCN were asked in January to investigate this issue and so far have failed to come up with any explanation."

http://notalotofpeopleknowthat.wordpress.com/2012/03/11/ghcn-temperature-adjustments-affect-40-of-the-arctic/#more-964

Mar 11, 2012 at 9:26 PM | Registered Commentermatthu

matthu - Mar 11, 2012 at 9:26 PM

You may find a possible reason if not an answer at:-

http://data.giss.nasa.gov/gistemp/2011/

"Footnotes"

"Exchange of continental and marine air masses in the Arctic implies that coastal meteorological stations should provide a better estimate of surface air temperature change than would measurements of ocean temperature. Satellite infrared observations, as discussed by Hansen et al. (2010), support our conclusion that the GISS analysis does not exaggerate Arctic temperature anomalies, indeed, the anomalies seem to be conservative."

Mar 11, 2012 at 9:58 PM | Registered CommenterGreen Sand

"In the course of collecting and analyzing data, researchers have many decisions to make: Should more data be collected? Should some observations be excluded? Which conditions should be combined and which ones compared? Which control variables should be considered? Should specific measures be combined or transformed or both?

It is rare, and sometimes impractical, for researchers to make all these decisions beforehand. Rather, it is common (and accepted practice) for researchers to explore various analytic alternatives, to search for a combination that yields “statistical significance,” and to then report only what “worked.” The problem, of course, is that the likelihood of at least one (of many) analyses producing a falsely positive finding at the 5% level is necessarily greater than 5%."

The above quote is from Roger Pielke Jr. "False Positive Science"
http://rogerpielkejr.blogspot.com/2012/03/false-positive-science.html

He explains the phenomenon so much better than I have managed to do. And obviously, scientists of the calibre who work e.g. at the Met office must be aware of this phenomenon. No?

Because, when e.g. you start wanting to add the Arctic temperatures into your analysis, is this simply because temperatures here have apparently been warming faster than the rest of the world and therefore match your modelled results more closely and would you have thought it so important to do this if this had not been the case?

In fact, why have you not considered adding more readings from the Antarctic into the pot? (Surely not because those temperatures don't add to the trend you are so desperately looking for?)

So my really sincere question to anyone from the Met Office is: what precautions do you routinely take to ensure that you don't allow this phenomenon to bias your numbers? And do you ever challenge others who may not be as diligent as you in taking these precautions, or should we simply afford them the benefit of the doubt?

Over to you, Richard.

Mar 15, 2012 at 9:58 PM | Registered Commentermatthu

Judith Curry has an article today which suggest that

HadSST3 selectively removes the majority of the long term variations from the pre-1960 part of the record. ie. it removes the majority of the climate variation from the majority of the climate record.

In a previous comment (Mar 9, 2012 at 11:50 PM) Richard claimed

I don't think it is "tampering". Analysis methods do get updated.

In reply, I point to Nelson's Funnel Experiment where tampering is simply described as

the adjustment of a stable process after each occurrence; treating every event as though it were special.

So, no: what appears to have been happening is not exactly analogous to tampering.

When you also get to choose which adjustments to retain and which to discard and there is inadequate data management to maintain a proper audit trail of adjustments which have been made, then this is somewhat worse than tampering.

Scientists all around the world (Australia, New Zealand, United States, UK, Russia, China) do understand what has been going on but have to contend with considerable reluctance to face up to it.

Just my opinion - but shared by many, I am sure.

Mar 16, 2012 at 9:20 AM | Registered Commentermatthu

matthu,

SST SERIES, AIR TEMPERATURE SERIES, AND THE WORLD WAR II SHIFT ADJUSTMENT

Not sure of the author, link is to Tallblokes site, certainly an interesting topic.

Mar 16, 2012 at 9:49 AM | Unregistered CommenterLord Beaverbrook

Hi matthu

My colleague Dr John Kennedy, lead author of the recent paper discussed in that post, has given some detailed responses on Judith's blog and is discussing the issues with the other folks there. If you have any questions about it, it's probably best to post them on the thread at Judith's.

Cheers

Richard

Mar 17, 2012 at 10:04 PM | Registered CommenterRichard Betts

Thank you, Richard - I will have a look at that thread.

Your reply, of course, focuses on one paper and not on the general principal which seems to be pervasive in climate science. It seems clear that you are reluctant to be drawn into this area of discussion. Let's leave it there.

Cheers

Matthew

Mar 18, 2012 at 7:42 AM | Registered Commentermatthu

Open letter to the Met Office:


Date: Thu, 22 Mar 2012 17:19:10
From: Paul Matthews
To: Press office, Richard Betts, Peter Stott, Stephen Belcher
Subject: Misleading web page on HADCRUT4


I write to complain about the misleading information
given out in the Met Office press release
http://www.metoffice.gov.uk/news/releases/archive/2012/hadcrut-updates

The page includes a table of rankings that is completely meaningless,
since the 2010 HADCRUT anomaly of 0.53 is only 0.01 above the 1998
value of 0.52, but the uncertainty is of the order of 0.1.
The line that will be picked up by the media,
(and already has been, as a quick search confirms, see
http://www.telegraph.co.uk/earth/earthnews/9153473/Met-Office-World-warmed-even-
more-in-last-ten-years-than-previously-thought-when-Arctic-data-added.html
http://www.bbc.co.uk/news/science-environment-17432194 )
is that there is a new 'ranking' in which
2010 is now the warmest year, not 1998.

This meaningless ranked table is, of course, not to be found in
the published HADCRUT4 paper, which does not mention ranking of individual years
at all.

It is exactly this kind of misleading propaganda put out by
climate scientists that is responsible for the increasing
distrust of the whole field by scientists from other areas.


Paul Matthews

School of Mathematical Sciences,
University of Nottingham,
University Park,
Nottingham NG7 2RD, UK

Mar 22, 2012 at 5:22 PM | Registered CommenterPaul Matthews

@Paul Matthews Mar 22, 2012 at 5:22 PM

Well said, Paul ... particularly:

The page includes a table of rankings that is completely meaningless,

When I looked at that table last night, I first thought there must be something wrong with my thought processes; because - given the introductory text and table caption "Annual global mean temperature record under HadCRUT3 and HadCRUT4" - I initially expected to see a "comparison" of HADCRUT3 and HADCRUT4.

"Self," I said after looking at the first row, "why are they comparing 1998 with 2010?"

So, consider it "confirmation bias" if you will, but I was really pleased to see your assessment of this, Paul :-)

Mar 22, 2012 at 11:55 PM | Unregistered CommenterHilary Ostrov

Hi Paul

I do share your concern about the risk of this nominal ranking being given more significance than it deserves (see my comment to Joe Romm about this, following his post at Climate Progress).

However, like it or not, it is the kind of question we get asked about, and we have the data to provide an answer (including uncertainties) so we do so - and are careful to give the uncertainties, as you can see.

If we didn't do that then someone else would simply do the ranking themselves, and may miss out the uncertainty estimates. It's not propaganda, it's just answering questions that we get asked!

As well as clearly including the uncertainty estimates, the news release doesmake clear that the update to record does not change the overall conclusion:

Updates have resulted in some changes to individual years in the nominal global mean temperature record, but have not changed the overall warming signal of about 0.75 °C since 1900.

Cheers

Richard

Mar 24, 2012 at 12:36 AM | Registered CommenterRichard Betts

Hi Hilary

why are they comparing 1998 with 2010?

Specifically to make it clear that the nominal "hottest years" in HadCRUT3 and HadCRUT4 are very close, and that the difference is well within the uncertainties!!!

Cheers

Richard

Mar 24, 2012 at 12:41 AM | Registered CommenterRichard Betts

Hi Richard, I posted this earlier, but in the midst of other stuff:-

I know you are very busy but if you get chance could you get somebody to shed light on the following?

Some days ago you pointed at the following MO page to explain the HadCRUt3 /Arctic issues:-

“Global-average annual temperature forecast”

http://www.metoffice.gov.uk/research/climate/seasonal-to-decadal/long-range/glob-aver-annual-temp-fc

At the bottom of the page is:-

Figure 3: The difference in coverage of land surface temperature data between 1990-1999 and 2005-2010. Blue squares are common coverage. Orange squares are areas where we had data in the 90s but don't have now and the few pale green areas are those where we have data now, but didn't in the 90s. The largest difference is over Canada.

Why did the MO not have the 2005-2010 Canadian land surface temperature data? I am not aware of any of the stations being closed? If they have been could somebody please point me in the right direction?

Many, many thanks for your replies and contribution.

Regards

Mar 24, 2012 at 10:54 AM | Registered CommenterGreen Sand

In an earlier comment I had noted:

given the introductory text and table caption "Annual global mean temperature record under HadCRUT3 and HadCRUT4" - I initially expected to see a "comparison" of HADCRUT3 and HADCRUT4.

"Self," I said after looking at the first row, "why are they comparing 1998 with 2010?" [emphasis now added - hro]

To which Richard Betts replied:

"why are they comparing 1998 with 2010?"

Specifically to make it clear that the nominal "hottest years" in HadCRUT3 and HadCRUT4 are very close, and that the difference is well within the uncertainties!!!

With all due respect, Richard, this sounds like bureaucratic bafflegab to me! As does the rest of the MO's "press release".

What is a "nominal" hottest year supposed to mean? And since the table in question specifically indicates that the "uncertainties" column pertains only to HADCRUT4, why would one infer that the "difference" between these two "nominal" hottest years (whatever that is supposed to mean) lies within the "uncertainties".

IOW, in the interest of "communicating" with an admitted layperson, would you care to try again and offer an explanation of this otherwise meaningless table in plain English :-)

And while you're at it, perhaps you could explain what one is supposed to infer from:

Updates have resulted in some changes to individual years in the nominal global mean temperature record, but have not changed the overall warming signal of about 0.75 °C since 1900.

I'm not sure how this 0.75°C might have been derived. But, as it currently stands, I would take this to mean that in the last 110 years, the average global temperature has risen considerably less than 1° C. So perhaps you could also explain (in plain English!) why we should be so worried about such a virtually imperceptible change.

Thanks.

Mar 25, 2012 at 9:15 AM | Unregistered CommenterHilary Ostrov

From reading the MO press release and watching Peter Stott's presentation I get a noticeable impression by omission that the IPCC predictions of temperature change by 2100 are on the extreme side and are superseded by the latest thought that a 0.75C rise over the last 100 years of industrial growth in the Western World is nothing to worry about.

Would this press release meet the criteria required for the Secretary of State to re-evaluate the 2008 climate change act targets and pass such advice to the Climate Change Committee?
Amendment of 2050 target or baseline year


(1)The Secretary of State may by order—
(a)amend the percentage specified in section 1(1);
(b)amend section 1 to provide for a different year to be the baseline year.
(2)The power in subsection (1)(a) may only be exercised—
(a)if it appears to the Secretary of State that there have been significant developments in—
(i)scientific knowledge about climate change, or

(ii)European or international law or policy,
that make it appropriate to do so, or(b)in connection with the making of—
(i)an order under section 24 (designation of further greenhouse gases as targeted greenhouse gases), or
(ii)regulations under section 30 (emissions from international aviation or international shipping).
(3)The developments in scientific knowledge referred to in subsection (2) are—
(a)in relation to the first exercise of the power in subsection (1)(a), developments since the passing of this Act;
(b)in relation to a subsequent exercise of that power, developments since the evidential basis for the previous exercise was established.
(4)The power in subsection (1)(b) may only be exercised if it appears to the Secretary of State that there have been significant developments in European or international law or policy that make it appropriate to do so.
(5)An order under subsection (1)(b) may make consequential amendments of other references in this Act to the baseline year.
(6)An order under this section is subject to affirmative resolution procedure.

Mar 25, 2012 at 10:22 AM | Unregistered CommenterLord Beaverbrook

Hi Hilary

Thanks for introducing me to a new word "bafflegab" - I'd not heard that before, but shall enjoy using it!

The point is, we get asked "what is the warmest year in the record?", and when we say "well it's very hard to say for sure because the uncertainties are larger than the differences between rankings" the response is "well what do the numbers actually say?" and it's true that you can take the numbers and put them in a ranked order, even if that doesn't particularly mean very much. So we give out the numbers and the uncertainties, so the information is out there (a good thing, no?). By "nominal hottest year" I mean "you can technically call it the hottest year if you like, but it may not actually be the exact hottest year".

If you want to see how the updates affect individual years or have other questions on the detail, please read the paper or feel free to download the data yourself and take a look. Our press release just aimed to address the questions that we know from experience are the most common regarding this kind of thing.

It's not for me to tell you whether to be worried about a 0.75 degree rise in global temperature or not. Please make your own decision about what you want to worry about!

:-)

Best,

Richard

Mar 25, 2012 at 10:23 AM | Registered CommenterRichard Betts

Richard, when you get asked "what is the warmest year in the record?", I don't see why it is so hard to say: "well the record shows that there has been no significant warming since 1998 although that temperature has probably been matched in 2010"?

How could you get criticised for that?

Mar 25, 2012 at 4:07 PM | Registered Commentermatthu

Matthu - plus 1

By not saying that, the Met Office gives the impression of 'spinning' the figures for policy..
and the explanation is weak, we get asked for it.. doesn't mean you should provide it in a manner to be 'spun' for political use.

Good communication, is clear and concise.. not the bafflegab we often see by very many scientific press offices.

Mar 27, 2012 at 11:58 AM | Unregistered CommenterBarry Woods

Thanks, Barry.

Though it would be nice if Richard (amongst others) were just a little more prepared to accept that this is what has been going on. In the meantime, we get the likes of Vicky Pope in The Guardian bemoaning the fact that science may be being misused (really?) and feigning concern that science may not always be being presented objectively.

Ho hum...

Mar 27, 2012 at 1:23 PM | Registered Commentermatthu

Richard,

There is a very informative discussion going on here.
There is a need for definitions of the complex models currently being used, something that I would like to clarify, as per your reply on March 14th in unthreaded. Discussion is open and friendly, any chance of an input or pointer to model definition?


Where did you hear that? That would be quite unusual, and as you say, quite unrealistic. We model the atmosphere as a fluid moving on an oblate spheroid rotating about an axis which is offset from the perpendicular to the plane of its orbit about the sun....

Cheers

Richard

Apr 6, 2012 at 9:47 AM | Registered CommenterLord Beaverbrook

Hi Richard,

I have some questions for you and the MO modelling experts about another recent paper from the McGill group.

Here is a brief summary of their conclusions:-

1/ At time scales longer than 10/30 years (the climate regime), the magnitude of observed temperature fluctuations increases with increasing scale.
2/ GCMs tested by the authors do not reproduce the observed scaling behaviour when unforced.
3/ With the partial exception of ECHO-G, forced runs of the tested GCMs are not much different.

Here are my questions:-

A/ What are the physical effects suspected by the MO of causing the scaling behaviour observed within the climate regime?
B/ Do the MO models incorporate simulations of these physical effects?
C/ Do the MO models reproduce the observed climate regime scaling behaviour?

Apr 10, 2012 at 8:01 AM | Unregistered CommenterPhilip Richens

I have had no reply to the email I sent to 4 people at the Met Office on 22 March, 3 weeks ago.

The lack of any response, plus Richard's statement that he shares my concern is as close as we are going to get to an admission of wrong-doing.
The argument that people would ask us anyway is of course nonsense, as pointed about by Matthu. The correct response to such an enquiry would be to say that it's inappropriate to draw up tables since the differences are much less than the uncertainties.

Apr 13, 2012 at 1:19 PM | Registered CommenterPaul Matthews

For a number of years I have had a one simple, single, question to the MO “is our(your) ability to predict the temperature of this planet improving or diminishing?”

So far I have only been directed to “hindcasts” which by definition have no relevance to the question whatsoever.

Today posted on WUWT:-

“Met Office – COPing to predictions”

http://wattsupwiththat.com/2012/04/14/met-office-coping-to-predictions/

It purports to contain the UK MO predictions from 1998 onwards!

In which case I will go away and see what if any actual forecasts were made and just how well they turned out?

Somehow I suspect the answer will be “scientifically” unclear whilst containing “policy” certainties!

Apr 14, 2012 at 11:38 PM | Registered CommenterGreen Sand

Richard,

I heard via the Today program this morning that the Midlands are now in an 'environmental drought' but could not find that expression in your Drought description .


There is meteorological drought which is essentially time without rainfall. There is agricultural drought which is a reduction in the amount of water available for crop growth. There is hydrological drought which is a reduction on the amount of water in rivers and in the ground. There is economic drought which concerns access to water. This has socio-economic implications as well.

The reason I ask is that in the East Midlands I am overlooking a field next to the Trent that is still water logged from last weeks rain, I cross the Trent in several places on a regular basis which does not look stressed, my garden in Central Midlands and my relatives gardens in West Midlands haven't had to be watered so far this year and yet the vegetables and plants are growing healthily. Fruit trees are budding and potatoes, carrots and onions are growing well, Rapeseed seems abundant in the fields.

Perhaps you could elucidate the details of an 'Environmental Drought' for me and how it is influenced by model projection?


Bearing in mind the different definitions of drought we can still assess how climate change may affect drought, and the amount of time spent in drought, by interpreting the output of computer climate models.

Apr 16, 2012 at 8:17 AM | Registered CommenterLord Beaverbrook

Greensand,

Willis is assisting with your enquiries.

Apr 16, 2012 at 8:33 AM | Registered CommenterLord Beaverbrook

Thanks Lord B, I will take a look and on past performance I expect Willis will be far more succinct and to the point!

Apr 16, 2012 at 3:06 PM | Registered CommenterGreen Sand