DMI polar data shows cooler Arctic temperature since 1958

From Frank Lansner at Hide the Decline

From DMI (Danish Meteorological Institute) we learn, that Arctic 80N-90N temperatures in the melt season this year is colder than average. This was the case last year too, while earlier years in the DMI analysis period (1958-2010) hardly ever shows Arctic melt season temperatures this cold.

This is how DMI temperature averages for Arctic 80N-90N  melt season appears when plotted to allow compare over time:

Fig2 (When i speak of “the melt season” i refer to the period where temperatures 80N-90N are above zero Celsius. The green line above is the DMI temperature average, a little over 0,9 Celsius)

It seems that average Arctic temperatures 80N – 90N in melt season of the years 2004, 2009 and 2010 are around 0,4-0,5K whereas the temperatures in 1991 and 1993 where around 1,3 K. In general DMI´s data (if correct) reveals a cooling from the mid 1990´ies till today.

The 80N-90N area of the Arctic is practically always ice covered. Therefore, the 80N-90N is perhaps not so affected by heat from the other areas of the Arctic that has been still more ice free in the period 1995-2007. Im not sure why DMI shows such a cooling trend for the 80N-90N area, but it could appear as if the ice covered areas of the Arctic has its own history of temperatures? And how should GISS data from distant land stations account for this?

Here´s how GISS temperature appears when comparing 1991 to 2009 for the Arctic Polar region:

Fig3

The Arctic melt season is mostly June and July. For both months the GISS Arctic temperature trend 1991 vs 2009 shows warming around 0,3-0,7K which is in contrast with the DMI trends of cooling of around 0,7K for the region.

Is it basically a convincing idea to use land/city/Airport temperatures for temperatures at sea? Give it a thought:

Imagine you stand on a boat 12 km from land…

Fig4

You want to know the Air temperature in 2 meters altitude. Which temperature would be most precise, the water temperature around the boat or the temperature from land ( measured at the city airport… ) ?

Now imagine the same situation, but this time you are 1150 km from land. Which temperature would you rely most on, the water temperature around the boat or the temperature from land (city/Airport) 1150 km away?

Since 1987, James Hasen, and thus GISS, har used a 1200 km radius in their global temperatures based on meteorological stations and thus extended land temperatures to cover a considerable ocean area.

Below a compare of SST with the temperatures GISS use for ocean areas.

Fig5

1) Left: GISS land temperatures including land temperatures to cover ocean areas.

2) Right: As 1) but now for the ocean areas the actual SST measured by the Hadley centre are shown.

Both pictures are from july 2010. From this illustration we see, that ocean areas represented by SST are poorly reflected by GISS land temperature data and the idea of expanding land temperatures to cover ocean area appears challenged?

Read the entire article at Hide the Decline

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jakers

Hm, don’t see the word “model” mentioned here, the “DMI temperatures” are spoken of as if they are data points. And their model changed twice. From their site:
“Calculation of the Arctic Mean Temperature
The daily mean temperature of the Arctic area north of the 80th northern parallel is estimated from the average of the 00z and 12z analysis for all model grid points inside that area. The ERA40 reanalysis data set from ECMWF, has been applied to calculate daily mean temperatures for the period from 1958 to 2002, from 2002 to 2006 data from the global NWP model T511 is used and from 2006 to present the T799 model data are used.”
REPLY: I don’t see your mention here of when we previously covered the issue, so here it is: http://wattsupwiththat.com/2010/07/28/giss-arctic-vs-dmi-arctic-differences-in-method/
There’s far more data in DMI than you might think. – Anthony

latitude

” In general DMI´s data (if correct) reveals a cooling from the mid 1990´ies till today.”
If you plot a trend from 1958, you get a steep decline.

Dave F

…when plotted to allow compare over time…
Should read “…when plotted to allow comparison over time…”

marek

Shouldn’t all temperatures be denominated in C instead of K?

Photographs of the ice correlate very well with DMI temperatures. There has been almost no melting at the pole during the last two cold summers.

Little Blue Guy

marek says:
August 5, 2010 at 2:47 pm
Shouldn’t all temperatures be denominated in C instead of K?

==============
Yes…
Unless the next sound you hear is the atmosphere solidifying… Which you wouldn’t actually hear, since there would be no atmosphere…

Tenuc

This temperature decline since 1990 can’t be right, because CO2 has increased dramatically since then and the IPCC says we will see the first evidence of CAGW at the poles???

ChickenLittle

Wouldn’t the warm ocean currents coming from the south have more impact on the arctic ice melting than the surrounding air?

kwik

Doesnt this aggrevate the CAGW crowd a bit?

Theo Goodwin

Anthony writes:
“Im not sure why DMI shows such a cooling trend for the 80N-90N area, but it could appear as if the ice covered areas of the Arctic has its own history of temperatures? And how should GISS data from distant land stations account for this?”
Sounds like real science. The truth is in the details and they are messy as all get out.

R. de Haan

Another interesting insight:
Researchers discover irrefutable proof that Arctic Sea Ice had disappeared in the mid 1800’s, at the end of the Little Ice Age.
http://www.c3headlines.com/2010/08/researchers-discover-irrefutable-proof-that-arctic-sea-ice-had-disappeared-in-the-mid1800s.html

bemused

“There’s far more data in DMI than you might think. – Anthony”
Hi Anthony,
A minor point of clarification. DMI don’t produce this data. The data comes from the initial conditions of the ECMWF weather forecast model after assimilation of observational data. DMI plotted the graph, but weren’t involved in the production of the data.
See my previous comments here:
http://wattsupwiththat.com/2010/07/28/giss-arctic-vs-dmi-arctic-differences-in-method/#comment-442773

Steven Goddard wrote,
“2) Right: As 1) but now for the ocean areas the actual SST measured by the Hadley centre are shown.
“Both pictures are from july 2010”
If they’re both from July 2010, then they’re not Hadley Centre SST data. From December 1981 to present, GISS has used Reynolds OI.v2 SST data, which is an NCDC product.

Ray

Looks like the hockey stick is pointing down.

Frank Lansner: Oops. I saw the Arctic reference and assumed the post was written by Steven, sorry. I’ll then redirect my comment to you.
You wrote, “2) Right: As 1) but now for the ocean areas the actual SST measured by the Hadley centre are shown.
“Both pictures are from july 2010″
Wrong! If they’re both from July 2010, then they’re not Hadley Centre SST data. From December 1981 to present, GISS has used Reynolds OI.v2 SST data, which is an NCDC product.
And as Zeke noted in a comment in one of your earlier posts, GISS acknowledges the Land Surface dataset with 1200km radius smoothing reads high. They keep it for sentmental reasons:
http://wattsupwiththat.com/2010/07/17/tipping-point-at-giss-land-and-sea-out-of-balance/#comment-434647
Also, please provide a link to the ERA-40 data you used to create the graph.

Henry chance

Does James Hansen have the satelite readings from 1958 to 1980 to refute this?

anthony holmes

Well , on checking the north pole web cam , which I have been assured by a member of the camera crew is correct , it is showing the cameras temperature is 11 centigrade , quite toasty for the north pole , my back yard in England is presently the same temperature – hope we do not mirror the north pole temperatures as we go into winter !!!!!

Steven Goddard: Please disregard my earlier (August 5, 2010 at 3:29 pm) comment. I saw the discussion of the Arctic and the use of the DMI data and assumed, incorrectly, the post was written by you. I’ve redirected the comment to Frank Lansner.
Sorry for the confusion on my part.

Frank Lansner: You wrote regarding Figure 6 in the remainder of your post:
“In the compare above, a few areas (between Sri Lanka and Singapore and around Spitsbergen and slightly more) has GISS ocean temperatures warmer than Hadley SST, but more often the GISS temperatures for oceans are warmer than the Hadley SST.”
First, you compared to the wrong SST dataset. GISS has used Reynolds OI.v2 for almost the last three decades. The differences you’re seeing between the GISS data over the oceans and the HADISST data may be due to the differences between Reynolds OI.v2 and the HADISST data you used incorrectly. Also, GISS includes land surface data from many islands and this may be causing some of the difference.

Bob,
Do you feel that the usage of NCDC or Hadley data would have any impact on Frank’s conclusions?

Bob, i use the options in GISS own utility:
http://data.giss.nasa.gov/gistemp/maps/
Try yourself, first witth empty ocean box. Then with the Had/reyn in the ocean box.
The differences i show are the differences GISS shows themselves. I just focus on the areas where both SST and GISS land temperatures for oceans are available to make it easier to see how huge the differences are.
And yes im aware that GISS has some of their stations on Islands, but non the less, the differences GISS show between their land projections and the SST they use appear considerable.

Ed Caryl

Data from the North Pole webcam is at:
http://psc.apl.washington.edu/northpole/POPS13_atmos_recent.html
The last temperature recorded was 1.9 C.

And Bob im perfectly aware that GISS has a LOTI index where they dont use these projected land temperatures much – however even in their LOTI index they use their Arctic land projections of temperatures that i focus on in this writing:
http://data.giss.nasa.gov/cgi-bin/gistemp/do_nmap.py?year_last=2010&month_last=6&sat=4&sst=1&type=anoms&mean_gen=06&year1=2010&year2=2010&base1=1951&base2=1980&radius=1200&pol=reg
And even though you think the GISS meteorological index from GISS in only for “sentimental” reasons, these data are still on the net for the public to see and use, and thus should be correct.

Ed Caryl
-1.9C

Bob, DMI does not only use ERA-40, they use to other sources/methods too, so i did the slave-work: I have magnified all DMI-maps to pixel size and counted pixel for pixel, so it took weeks.
I understand that you want the original data to work with, so would I, but still, you should honestly not miss the obvious point that recent years according to DMI has colder temperatures in the melt season than the old years (!)
Go to the DMI site and you will fast conclude that im just telling you what these data actually says quite clearly.

Frank,
Well done. It is a unfortunate that some official sites release graphs without the digital data which they were plotted from.

stevengoddard says: “Do you feel that the usage of NCDC or Hadley data would have any impact on Frank’s conclusions?”
Yes. Regarding his Figure 6, there are differences between the HADISST and OI.v2 SST datasets. But there is basically no difference between the GISS12o0km radius smoothing and the source Reynolds OI.v2. Refer to the following comparison.
http://i35.tinypic.com/2lc1t11.jpg
I used that area of the South Pacific because GISS doesn’t have any island surface station data in the region to skew the results. The Reynolds OI.v2 data is a noisier SST dataset than the HADISST. And the GISS data (1200km radius smoothing) for that area is slightly less noisy than the source Reynolds OI.v2 data.
If Frank is going to write a post complaining about GISTEMP, he should at least understand what SST data they use.

rbateman

Ed Caryl says:
August 5, 2010 at 4:27 pm
Nice link. The current DMI 80N reading is generous, being that the webcam is at 85N.

Ed Caryl

Oops. Missed the minus sign. (weird column structure) My point was that the 11 degrees seen in the webcam image is likely the internal temperature of the camera.

Jay

Oh no, its worse than we thought.
As the graph above titled “Average arctic (80N-90N) temperature during melt season. source DMI”
clearly shows the temperature is declining from 1992 to the current data. And if I do my eyeball of that trend within 20 years, the temp in melt season may be 0C or lower.
Quick -Hide the Decline

Robert

It appears that the decrease in temperatures at the artic region should probably be increasing the volume, well slowing the rate of decrease of volume at the artic. Now that the PDO is into its cold phase, and that the AMO should be reversing in the near future the artic sea ice extent and volume should increase a large amount in the coming years, and if the artic temps continue on this trend, there should be very little summer melt from now on.
Ironic how John Kerry posted a statement saying ice free artic in the summers in 5 years, and now it looks like we will be gaining ice for a long time

Frank Lansner says: “The differences i show are the differences GISS shows themselves. I just focus on the areas where both SST and GISS land temperatures for oceans are available to make it easier to see how huge the differences are.”
But GISS does not represent that the dTs data where it extends out over the oceans is SST data or that it would resemble SST data.
You wrote, “And yes im aware that GISS has some of their stations on Islands, but non the less, the differences GISS show between their land projections and the SST they use appear considerable.”
They should have considerable differences. They are different data, illustrating different things.
You wrote, “And even though you think the GISS meteorological index from GISS in only for “sentimental” reasons, these data are still on the net for the public to see and use, and thus should be correct.”
But you have not shown that it is incorrect. In the areas where the dTs data extends out over the oceans, do you have any proof that is not extrapolated and interpolated correctly from the land surface data? As I wrote above, GISS is not representing that will equal SST data. You assume the two should be equal and that is your error.

Bob,
Frank’s post is about the discrepancy between DMI and GISS. Regardless of which of the two data sets the GISS site allows you to choose from (Hadley or NOAA) you get the same answer.
So, I would suggest that you take your complaint to GISS for claiming to use a data set which you think they don’t use.
http://data.giss.nasa.gov/gistemp/maps/

Steven Goddard: You wrote, “Frank’s post is about the discrepancy between DMI and GISS.”
Actually, Frank’s shifts to another subject.
You wrote, “Regardless of which of the two data sets the GISS site allows you to choose from (Hadley or NOAA) you get the same answer.” and continued, “So, I would suggest that you take your complaint to GISS for claiming to use a data set which you think they don’t use.”
I have no compaint. Unlike some others, I understand what datasets they use on the mapmaking page, because they state what data is used. And I also understand which of the two is the official dataset. Their official SST dataset is made up of HADISST from Jan 1880 to Nov 1981 and Reynolds OI.v2 SST data from December 1981 to present.
GISS added the ERSST.v3b SST data to their mapmaking webpage back in February. And they refer to it in the draft of the Hansen et al (2010) paper:
http://data.giss.nasa.gov/gistemp/paper/gistemp2010_draft0803.pdf
And in Hansen et al (2010) they also confirm their official SST dataset. Refer to page 26. They write, “The standard GISS global analysis uses the concatenated HadISST1+OISST data set, as described in the main text. Any of the alternative ocean data sets described here would yield slightly greater global warming, both in recent decades and on the century time scale.
“Until improved assessments of the alternative SST data sets exist, the GISS global
analysis will be made available for both HadISST1+OISST and ERSST+OISST. The HadISST1 concatenation with OISST will continue to be based on equating means for 1982-1992, as it always has been in the standard GISS analysis. The ERSST+OISST concatenation will be as described in the main text of this paper. HadISST1+OISST will continue to be our standard product unless and until verifications show ERSST+OISST to be superior.”
So it appears they’re planning to shift to the ERSST.v3b data and in the following post, I showed how that would increase their 20th century trend, as they acknowledge:
http://bobtisdale.blogspot.com/2010/02/when-did-giss-add-ersstv3b-data-to.html
And I followed up on that post here:
http://bobtisdale.blogspot.com/2010/03/giss-acknowledges-addition-of-ersstv3b.html

Frank Lansner: You wrote, “however even in their LOTI index they use their Arctic land projections of temperatures that i focus on in this writing:
http://data.giss.nasa.gov/cgi-bin/gistemp/do_nmap.py?year_last=2010&month_last=6&sat=4&sst=1&type=anoms&mean_gen=06&year1=2010&year2=2010&base1=1951&base2=1980&radius=1200&pol=reg
The link you provided is to a map, not to a post you wrote about GISS using Arctic land surface data out over the oceans.

Phil's Dad

Jay says:
August 5, 2010 at 5:34 pm
Oh no, its worse than we thought.
…And if I do my eyeball of that trend within 20 years, the temp in melt season may be 0C or lower.

I make it ten years before there is no melt below 90N (or is that above 90N – which way is up?)
It even worster than we thought!

Billy Liar

anthony holmes says:
August 5, 2010 at 3:46 pm
Well , on checking the north pole web cam , which I have been assured by a member of the camera crew is correct , it is showing the cameras temperature is 11 centigrade …

Was it the leprechaun who lives inside the camera that told you that?

Phil's Dad

Bob Tisdale says:
August 5, 2010 at 5:43 pm

With the greatest of genuine respect (as this is very much your area) when you say;

“…do you have any proof that is not extrapolated and interpolated correctly from the land surface data?”

…isn’t the point that it shouldn’t be done at all (even if technically handled correctly)
The coast is an important/significant meteorological boundary and ignoring that in the global temperature picture surely gives an incorrect overall reading.
I am way outside my comfort zone here but I think I see what Frank is driving at.

Amino Acids in Meteorites

Glad to see this post. I think it’s important for showing what is really happening with Arctic temperatures for a contrast to what GISS is showing.

MichaelM

Although Bob Tisdale has made many valid criticisms of Frank’s procedures, I think the central theme of his post still bears careful consideration, as Steven Goddard pointed out.
Certainly GISS does not cover over the SST data with land data in their final product, but they do more or less that very thing in the artic. With little station data, they use Hansen’s 1200km smoothing (a peer-reviewed method)to ‘fill in’ the artic with a trend that diverges from that of DMI .
Now who is right? I don’t know; but they can’t both be right. Anyways, Willis Eschenbach posted a while back dismantiling the 1200km correlation thesis (IMHO).
_MichaelM

GregO

Ed Caryl – thanks for the link showing the cooling at the north pole. Wow that looks cold to me for August!
I just can’t help but wonder if we aren’t headed for a b i g chill in the future…

Fuzzylogic19

R. de Haan says:
August 5, 2010 at 3:22 pm
Another interesting insight:
Researchers discover irrefutable proof that Arctic Sea Ice had disappeared in the mid 1800′s, at the end of the Little Ice Age.
***
Irrefutable? What’s your definition of irrefutable. Then again, whatever it is, it will be ‘irrefutable’.

MichaelM says:
August 5, 2010 at 8:18 pm
“Although Bob Tisdale has made many valid criticisms of Frank’s procedures..”
Try not to generalize. Bob recently made a long nice illustrated article showing some consistensy between NCDC, CRU and GISS land data, because he thought that I was attacking the GISS land data when I was not. I was attacking the weighting of GISS land data. So the whole point of the article was hard to find for me and it really confused me a long time.
– But I did make a dumb mistake thatBob then eventually pointed out in the comments.
But Michael, please go through my site: http://www.hidethedecline.eu and see if “franks procedures” generally have a problem before you just write like this.
Bob: I think its good that you want the sceptic forums to be of highest possible quality, but i cant help wondering why I dont see any excitement in your writings of the central element in my findings? Honestly dont you find it interesting that DMI actualy shows a cooling 80N-90N ?? Why not one word of enthusiasm?
In april (i think) I made a story about La Nina “shark” at joanne Novas site indicating that La Nina would come soon, and PANG the day after you wrote a whole article that nobody should take notice of this “fuss” that one should not expect La Nina. But what happened… ?
So we can all make mistakes, we should just help each other in a good way, motivate each rather than the opposite.
K.R. Frank

Roger Knights

Bob Tisdale says:
August 5, 2010 at 3:43 pm
Frank Lansner: Oops. I saw the Arctic reference and assumed the post was written by Steven, sorry.

It would help if thread-author’s names were made more prominent, by being for instance boldfaced, enlarged, and/or centered.

Phil’s Dad: You wrote, “…isn’t the point that it shouldn’t be done at all (even if technically handled correctly)”
The GISTEMP land surface dataset that GISS identifies as dTs is a carry over from an old paper in which GISS attempted to reproduce global surface temperature without using SST data, because the SST data was so sparse in the 1980s. According to a comment that I linked above by Zeke Hausfather…
http://wattsupwiththat.com/2010/07/17/tipping-point-at-giss-land-and-sea-out-of-balance/#comment-434647
…GISS maintains it for sentimental reasons. Personally, I wish it didn’t exist, because it adds confusion.
You wrote, “The coast is an important/significant meteorological boundary and ignoring that in the global temperature picture surely gives an incorrect overall reading.”
Agreed. Extending that land surface data out over the oceans provides a significant bias.
You continued, “…but I think I see what Frank is driving at.”
I believe I see what Frank is driving at, too. I wrote a post about how GISS deletes SST data in the Arctic and Southern Oceans and extends land surface data out over the oceans:
http://bobtisdale.blogspot.com/2010/05/giss-deletes-arctic-and-southern-ocean.html
But Frank’s post shifts out of the Arctic, possibly to illustrate the bias created by the land surface data. But in his discussion of it, he has identified the SST dataset incorrectly. In June 2010, GISS does not use Hadley Centre data. If Frank had written “Hadley/Reynolds” I probably would not have commented about his post.

MichaelM wrote: “Certainly GISS does not cover over the SST data with land data in their final product, but they do more or less that very thing in the artic.”
Just to clarify, it’s really not a “more or less” thing. They purposely delete SST data for much of the Arctic so they can replace it with land surface data, which has risen at a higher rate.

Nylo

Please keep in mind that GISS doesn’t pretend that land temperature is equal to sea temperature 1200km far. GISS deals with temperature anomalies. What GISS says is, no matter what the true temperatures at the airport and at the sea are, if the airport temperature is 0,5K higher than normal for the airport, the temperature at the sea will probably be 0,5K higher than normal for that place at the sea.
Not that I think that this is a valid assumption, but it is definitely not the same as in the “what’s the temperature in my boat?” example provided.

Bob, you write: “Frank had written “Hadley/Reynolds” I probably would not have commented about his post.”
Its true, its a typo, it should have been “Hadley/Reynolds” as this is the data I show and use.

Rhys Jaggar

Look at the DMI graphs: you’ll see that ‘warmer’ temperatures are at the coldest times, but ‘summers’ are cooler.
How does that all fit together?

Frank Lansner: You wrote, “Bob: I think its good that you want the sceptic forums to be of highest possible quality, but i cant help wondering why I dont see any excitement in your writings of the central element in my findings? Honestly dont you find it interesting that DMI actualy shows a cooling 80N-90N ??”
Not particularly. The majority of the DMI data is from the ECMWF ERA40 computer model reanalysis, and if you’re not aware of it, ERA40 has a higher monthly Arctic surface temperature trend (80N-90N) from 1958 to 2002 than GISTEMP.
http://i33.tinypic.com/2wgt92d.jpg
You wrote, “In april (i think) I made a story about La Nina ‘shark’ at joanne Novas site indicating that La Nina would come soon, and PANG the day after you wrote a whole article that nobody should take notice of this ‘fuss’ that one should not expect La Nina. But what happened… ?
“So we can all make mistakes, we should just help each other in a good way, motivate each rather than the opposite.”
Are you implying that I made a mistake in that post? Because there is none. Here’s a link:
http://bobtisdale.blogspot.com/2010/05/typical-average-el-nino-traditional-el.html
The intent of the post was to illustrate that very few El Nino events are followed by La Nina events. I did not make a prediction that there would be no La Nina. In fact, my closing comment was, “Will a La Nina follow the 2009/10 El Nino? Considering that only 2 of 10 El Nino Modoki events since 1950 were followed by La Nina events, the odds are against it. But nature does provide surprises.”
And with respect to your thinking I wrote that post in response to your “The La Nina shark rises to bite” at Jo Nova’s, the date on your post at Jo Nova’s is May 2, 2010, but my post was dated May 1, 2010. And I wrote it months before it was posted. I even noted that in the second paragraph, “A number of months ago I noticed some of my visitors arrived from Google searches of ‘typical El Niño’ or ‘average El Niño’. I prepared this post for them back then but got sidetracked and never posted it.”
So don’t think my posts are written to prove that yours are wrong.