UPDATE: the question has arisen about “occupied” aka “manned” weather stations in Antarctica (Stevenson Screens etc) versus the Automated Weather Stations. This picture on a postage stamp from Australia, celebrating the Australian Antarctic Territory in 1997, may help settle the issue. Note the Stevenson Screen near the “living pod” on the right.
Here is the larger photo of the first day of issue card, the Stevenson Screen is also just visible above the snowbank in the lower right. Rather close to human habitation I’d say. Looks like its in the middle of an AHI (Antarctic Heat Island).
Here’s another picture of a Stevenson Screen close to a building in Antarctica, from the British Antarctic Survey:
![[10004058]](http://www.photo.antarctica.ac.uk/external/guest/image/water/70/10004058)
Location: Fossil Bluff, Alexander Island
Season: 1994/1995
Photographer: Pete Bucktrout
It seems that folks are all “wild about Harry” over at Climate Audit, with the revelations occurring there, and no good kerfluffle would be complete without some pictures of the weather stations in question. It seems a weather station used in the Steig Antarctic study , aka “Harry”, got buried under snow and also got confused with another station, Gill, in the dataset. As Steve McIntyre writes:
Gill is located on the Ross Ice Shelf at 79.92S 178.59W 25M and is completely unrelated to Harry. The 2005 inspection report observes:
2 February 2005 – Site visited. Site was difficult to locate by air; was finally found by scanning the horizon with binoculars. Station moved 3.8 nautical miles from the previous GPS position. The lower delta temperature sensor was buried .63 meters in the snow. The boom sensor was raised to 3.84 m above the surface from 1.57 m above the surface. Station was found in good working condition.
I didn’t see any discussion in Steig et al on allowing for the effect of burying sensors in the snow on data homogeneity.
The difference between “old” Harry and “new” Harry can now be explained. “Old” Harry was actually “Gill”, but, at least, even if mis-identified, it was only one series. “New” Harry is a splice of Harry into Gill – when Harry met Gill, the two became one, as it were.
Considered by itself, Gill has a slightly negative trend from 1987 to 2002. The big trend in “New Harry” arises entirely from the impact of splicing the two data sets together. It’s a mess.
So not only is there a splice error, but the data itself may have been biased by snow burial.
Why is the snow burying important? Well, as anyone skilled in cold weather survival can tell you, snow makes an excellent insulator and an excellent reflector. Snow’s trapped air insulative properties is why building a snow cave to survive in is a good idea. So is it any wonder then that a snowdrift buried temperature sensor, or a temperature sensor being lowered to near the surface by rising snow, would not read the temperature of the free near surface atmosphere accurately?
As I’ve always said, getting accurate weather station data is all about siting and how the sensors are affected by microclimate issues. Pictures help tell the story.
Here’s “Harry” prior to being dug out in 2006 and after:
Harry AWS, 2006 – Upon Arrival – Click to enlarge.
Harry AWS, 2006 – After digging out – Click to enlarge.
You can see “Harry’s Facebook Page” here at the University of Wisconsin
It seems digging out weather stations is a regular pastime in Antarctica, so data issues with snow burial of AWS sensors may be more than just about “Harry”. It seems Theresa (Harry’s nearby sister) and Halley VI also have been dug out and the process documented. With this being such a regular occurrence, and easily found within a few minutes of Googling by me, you’d think somebody with Steig et al or the Nature peer reviewers would have looked into this and the effect on the data that Steve McIntyre has so eloquently pointed out.
Here’s more on the snow burial issue from Antarctic bloggers:
The map showing Automated Weather Stations in
Antarctica:
Click map for a larger image
The Gill AWS in question.
From Polartrec
Theresa was placed at this location partly to
study the air flow in the region. Looking out the window of the plane we can
definitely see the air flowing!!! Jim estimates the wind at about 25 miles per
hour.
Wind blown snow at Theresa
With the temperature around 0F the wind chill
was about 20 below, it is obvious this is going to be quite a chore.
Starting to dig out Theresa
The weather station has not been working, so
George needs to figure out what is wrong with it and then fix it. The station is
almost buried in the snow so we will also need to remove all of the electronics,
add a tower section and then raise and bolt all of the electronics and sensors
back in place.
George unhooking the cables.
After refueling the plane, with the fuel in
the 55 gallon drums, Jim and Louie helped dig down to the electronics boxes that
were completely buried plus they built us a wind break that made huge difference
in helping us not be so cold. After about 4 hours we are almost through. As I am
hanging onto the top of the raised tower in the wind, one bunny boot wedged onto
the tower bracing, the other boot wrapped around the tower, one elbow gripping
the tower, my chin trying to hold the wind sensor in place and both bare numb
hands trying to thread a nut onto the spinning wind sensor I really appreciate
the difficulty of what is normally Jonathan’s job. After checking to make sure
Theresa is transmitting weather data we board the plane and head to Briana our
second station.
Notice the difference between this
picture and the first one of Theresa.
From Antarctic Diary
More movement
It’s been another flat-out week. The vehicle team have dug
up and moved the Drewery building, which was getting do buried snow was
almost up the windows. Team Met have been on the move too – all the
remaining instruments are now bolted securely to the Laws roof, so we headed
up the the Halley VI building site to relocate the weather station.
Jules starts digging out the weather station
Only 15km away, the Halley VI site looks a lot like Halley V. It’s flat,
white and snowy. Very snowy. The weather station had about 1.5m built up
around it!
Jules and Simon recovering the solar panel
In the hole!
The weather station was a survey reference point for the build project so we
had to find a suitable replacement. Could this be Antarctica’s first
pole-dancing venue?
Penguin Party memories…
After an hour or so sweating it our with shovels, the weather station popped
out and was loaded onto the sledge. Like the reference point, the station’s
new location had to be precise as vehicles are banned from the upwind
section of the site to keep that area ultra-clean for future snow-chemistry
experiments.
Weather station on the move
Driving on a compass bearing and GPS track, we found the new site just under
a kilometre away.
The final setup
UPDATE: here’s another buried station story from Bob’s Adventures in cold climes. Apparently this station is used as a reference for some sort of borehole project.
I dig weather stations
My main task for today was to get a start on raising my weather station. I’d installed it 2 years ago, and with the high accumulation at Summit, it’s getting buried. The electronics are all in a box under the snow, and the only things visible at the surface were the anemometer for measuring wind speed and direction, the thermistor for measuring air temperature, and the solar panel to keep the batteries charged.
The buried weather station. The flat green bit is the solar panel, which was about 1.5 meters off the surface when I installed the station. Can you guess why I would mount it facing down?
In the morning I downloaded all the data from the station, and checked to see that it was all in order. Then it was time for digging. I’d carefully made a diagram when I inastalled the station, so I knew exactly where to dig. A couple of hours later I’d found my box!
At the bottom of the pit with the datalogger electronics.
I brought everything up to the surface, and then was about to fill in the pit, when I realized at least one more scientist at Summit might want to make measurements in it; the pit’s already dug! So tomorrow I’ll help Lora with some conductivity measurements, then fill in the pit, re-bury the box just beneath the surface, and it’ll be ready to go for another 2 years!
And there’s more….
The Australians seem to have AWS problems as well. From the Australian Antarctic Division:
On Monday two groups headed out, with Largy and Denis going up to the skiway to check on the condition of the equipment stored there for the winter and beginning preparations for the coming summer flying season.
Bill, Brian and Ian went up to the Lanyon Junction Automatic Weather Station (AWS) to check its condition and retrieve some of the sensors in preparation for the annual servicing of the various remote units.
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And the University of Maine, participating in USITASE, has the same troubles, they write:
We reached our first major destination at the end of today’s travel, the site of the Nico weather station. There are several automatic weather stations spread out over the surface of Antarctica. These stations measure things like temperature, wind speed and wind direction and then relay this data back to scientists via satellite. Anything left on the surface of the snow will eventually be drifted in and buried by blowing snow. This particular weather station (NICO) has not been seen in several years. They tried to locate it via airplane a few years ago and were unsuccessful. Our task was to find the weather station, record its position with GPS, and mark the location with flags so that in the near future, the weather station can be raised and serviced.
We arrived at the coordinates of the station around 10 pm. Our initial scans of the horizon were not productive, so Matthew and John took the lead tractor (with our crevasse-detecting radar) out to survey a grid near our stopping point. The radar should detect a large metal object like a weather station, but the survey was also unsuccessful. After a fine pasta and tomato sauce dinner, John went outside for an evening constitutional. He saw a shiny object out in the distance – further inspection with a pair of binoculars determined that it was the top of the NICO weather station! Several of us marched out to the station, which was actually about a half mile distant, marked the location with bright orange flags and recorded the position via GPS for future reference. Only the top foot or two of the station was still visible. John was in exactly the right place at the right time to see a reflection from this object while we were near the kitchen module, and so allowed us to complete our first task successfully.
Tomorrow, we drive on.
This regular burial and digging out of stations brings the whole network of AWS stations to be used as sensitive climate measurement stations into question.
I’ve had difficulties getting to CA’s page today, does that mean the site’s getting as much attention as it can handle?
I’ve been learning that the Arctic and the Antarctic are two very, very different environments. Antarctic snow just keeps piling on, up up up, burying everything pretty fast. A “polar opposite” to the Arctic, where the sea ice forms, melts, forms, melts – and I wonder if it gets melted from underneath too, as it gets heavier and starts to sink deeper into the warmer ocean (only the highest ocean is freezing, after all, since freezing water rises).
REPLY: CA was overwhelmed, but some adjustments to the server were recently made, and it should be OK now. – Anthony
Excellent work going on down there – too bad there are some willing to corrupt the data.
OT but should be of interest. Al Gore spoke to school children and told them He also told them not to listen to the ‘old people’ because they didn’t understand what is going on. Indoctrination anyone?
OUTSTANDING work. Congrats all around to you, SteveM and everyone else who toiled away. I just KNEW the scientists hadn’t been “doing the calcualtions in there head” or “on back of envelopes”. In reality, they had been ignoring obviously corrupted data, just like a real scientist is supposed to do.
Again, marvelous work gentlemen….
From your “Gill” link through the “Archived Gill AWS Data” link shows
“Ten-minute interval data for Gill AWS” data for all months of years 2003 through 2006, yet on the same page listing of “Three-hourly interval data for Gill AWS” is completely missing all data from 2003 to and including 2006.
On the surface so to speak, it seems odd that ten minute intervals of data would be recorded, but not three hour intervals.
So was snow burial more of an issue in the 1950s or ias it more of an issue now? Let’s accept that getting data from the Antarctic is a tough call. Why the concern about this now, following Steig’s paper which found a warming trend, when there was no concern expressed about it before, when the general meme was that the Antarctic was cooling? Why do you energetically challenge findings that suggest supposed warming whilst uncritically accepting any evidence of supposed cooling?
Thanks for this wonderful article.
You are right, a picture tells more than a thousand words.
The speed of accumulation of snow is incredible.
We already saw the pictures from the polar stations that had to dug out despite the use of telescopic adjustable foundations.
At http://www.iceagenow.com/Growing_Antarctic_Ice_Sheet.htm
you can find a picture of a crane and power transmission towers buried in the Antarctic snow.
This article effectively destroys all claims of rising Antarctic temperatures.
Ron de Haan (16:25:53) :
This article effectively destroys all claims of rising Antarctic temperatures.
And does it also destroy all claims of falling Antarctic temperatures?
REPLY: Interesting question. The key would be to demonstrate how these issues could result in a cooling bias. A station buried under snow will of course be warmer than the surface air not only for the insulation from that surface air it provides, but also from any heat from the electronics package slowly radiated through the snow to the temperature sensors. Without wind to carry away such waste heat from the electronics, IMHO the only place for that waste heat to go is outward and upwards and eventually to be detected by the sensors.
Show how snow burial of an AWS could result in a cooling bias. Maybe I’ve missed something. – Anthony
Simon: “Why do you energetically challenge findings that suggest supposed warming whilst uncritically accepting any evidence of supposed cooling?”
Because cooling is almost never artificial.
What a place; I need to go there.
Before the stampeding herd arrives, and since we are talking Antarctica; I notice that the thread on Antarctica warming per Eric Steig et al seems to have sublimed.
I have a bone to pick with someone whose name sadly I forgot and since I can’t find the thread, I can’t call him out by name.
But somewhere in that thread, I had made the statement that in parts of Antarctic such as South pole, or Vostok Station, the atmosphere was likely to be essentially devoid of water (very low vapor pressure) and possibly of CO2 as well, since at Vostok the temp can get as low as about -90C.
So whoever it was, that commented on that; he was unequivocal in his opinion that “that was total nonsense”, and by inference I was a total idiot; and he advised me to look at the CO2 phase diagram; which he kindly pointed to, such as :-http://scifun.chem.wisc.edu/chemweek/CO2/CO2_phase_diagram.gif
So I did that and then meekly submitted that he was correct, and that was nonsense; but I did not admit to being a total idiot; which I am not.
But I did launch massive research project into the matter; which finally ended a few minutes ago in discussions with my immediate boss; and since he is a PhD physicist,a nd an HP Fellow; who am I to argue with him.
So here is the situation; The CO2 phase diagram which Mr_X referred me to shows that CO2 sublimes at -78.5Deg C and one atmosphere pressure, and the soli/solid+gas phase boundary goes from about -135 deg C and 0.001 atmospheres to-56.6 deg C at 5.11 atmospheres which is the triple point.
Whence Mr_X declared that CO2 at 385 ppmv could not possibly precipitate out and form CO2 snow, even though I talked with a chap who claimed he walked on CO2 snow at the south pole, while making solar insolation readings.
Well here is what Mr_X failed to realize. That one atmosphere pressure at
-78.5 C sublimation point is the TOTAL ATMOSPHERIC PRESSURE; it is NOT the partial vapor pressure of CO2.
Considered at the atomic level at the solid/gas interface, all that the dry ice surface molecules know, is that they keep getting clobbered from above by some energetic projectiles, of unknown species exchanging energy and momentum between the species.
So what determines the escape rate of CO2 molecules from the surface is the kinetic energy exchange going on with the gas molecules, and it matters not what species that is; only the net exchange rate of energy/momentum matters.
So the equilibrium diagram definitely is a total pressure condition.
The ice under an ice skate blade, cares not whether the applied pressure comes from air or steel.
Therefore we can say with a fair likelihood of being correct, that the sublimation point of CO2 is at -78.5 deg C at 1.0 atmospheres of total pressure from all sources; which by dalton’s law would be the sum of all the partial pressures of all the atmospheric components, including the 385 ppm of CO2 gas.
So at -90 deg C, where Vostok can reach at times, the equilibrium pressure is about 0.3-0.4 atmospheres TOTAL PRESSURE.
Therefore at around -90 C at Vostok, and one atmosphere total air pressure, solid CO2 is quite stable, so precipitation of CO2 snow is quite possible, and in fact it is possible any time the air temperature drops below -78.5 deg C.
Therefore I hereby declare, I am not an idiot, and my assertion was not total nonsense.
So when Mr_X arrives here, I would appreciate an apology.
George
And thanks for the phase diagram Mr_X; there’s no such thing as too much information.
Reply: That would have been Phil. And this was the post.. Moderators have much better search tools available. For better or worse ~ charles the moderator.
Simon Evans,
Not exactly, but it does call into question the use of statistical techniques to infill and extrapolate data from suspect reference points.
It looks to me like solar panels are lower than the temp sensors. This would seem to indicate that the stations would quite broadcasting before the temperature sensors go below the snow (looks like 6″ to 12″ above the solar panel). Of course the height of the sensors above the snow will decrease from 6′ or so as the snow “buries” the station.
Simon Evans — Why the concern about this now, following Steig’s paper which found a warming trend, when there was no concern expressed about it before, when the general meme was that the Antarctic was cooling?
It’ll take “The data for years says one thing and Steig says another, so why is that?” for a thousand, Alex.
Maybe it’s just me, but I have the distinct impression that if Gavin were to cough, your head would compress.
Reply: Stick to civil discourse ~ charles the moderator.
Can’t quite reconcile “Last Two Days of Observations” link to “Text Data” with seemingly multiple data with no rhyme or reason, out of order and conflicting, for example:
ID Date Time Temp
8911 2009035 134740 -30.1
8911 2009035 134740 -14.1
It seems also that maybe half of the entry dates should have been one day off, instead of them all being “2009035” apparently the 35th day of 2009.
jeez (16:41:09) :
Simon Evans,
Not exactly, but it does call into question the use of statistical techniques to infill and extrapolate data from suspect reference points.
But I’m not sure that it does, jeez – after all, the exercise has been referenced against IR satellite readings which maybe (I don’t know for sure, and I expect this work to be followed up and either confirmed or else challenged) give us a better assessment of Antarctic temperatures than we had before. Let’s all agree that the station data is poor and the MSU data is poor (for reasons of altitude, etc.).
I’m sure you can see my point. The impression is that the obvious limitations in Antarctic data are only challenged if it suits the agenda. If I had posted here before the Steig paper saying that the Antarctic station data was unreliable and that, therefore, the ‘cooling’ was meaningless I fully expect that I would have been howled down. It’s fair enough if people are expressly pursuing one side of the argument, so to speak, but any suggestion of scientific disinterest is hard to swallow.
REPLY: Simon see my question above – anthony
G Alston (16:47:18) :
Simon Evans — Why the concern about this now, following Steig’s paper which found a warming trend, when there was no concern expressed about it before, when the general meme was that the Antarctic was cooling?
It’ll take “The data for years says one thing and Steig says another, so why is that?” for a thousand, Alex.
Maybe it’s just me, but I have the distinct impression that if Gavin were to cough, your head would compress.
Cut out the ad homs and stick to the discussion – you do your argument no credit by choosing to resort to personal sneers.
Reply: Moderators agree with Simon. Missed that one. I’m leaving in for continuity, Anthony may think otherwise. ~ charles the moderator
We should also not forget the example of the so-called “lost squadron” f P-38s and B-17s that got abandoned on Greenland in 1942, and were discovered around 2002 or so under 262 feet of snow/ice which presumably dposited ove 60 years. Although some of the planes were crushed somewhat; ne of the P-38s was recovered and is flying again. But the point is, there is no evidence that the planes sank into the ice. The ice was far too cold to melt under the pressure of the planes; so all that 262 feet was 60 years of precipitation on Greenland; and I don’t see why Greenland and Antarctica would be totally diffrent, other than the altitudes and greater size of Antarctica.
Now if Anthony will do a “site bias” examination of the manned Antarctic stations.
I can’t imagine that at 50 below temps the heating of the buildings, runways, etc. at the manned sites don’t influence the readings. Are the temp sensors on top of the buildings to avoid cover by the snow?
Just a thought . . .
H
Anthony,
Simon see my question above – anthony
Ok, thanks. Of course I don’t know, and can only speculate. If maintenace of stations has improved over the record period, then one would expect a cooling bias, with earlier periods being more subject to biased warming from snow cover than later…? Of course, the opposite could be the case if maintenance has degenerated (and indeed, perhaps there have been periods of better or worse maintenance during the record period). I simply don’t know, but I certainly don’t see why the snow issue necessarily implies a warming bias over time.
What I would like to know is whether the issue with ‘Harry’, or any other of these issues, are specific to the Steig paper. If they are, then fair criticism. If, however, they are raw issues with all the records for the Antarctic, thern that is another matter. It might be that Steig et al are being challenged for trying to make the best of a bad job.
Great post Anthony.
I hereby give to humanity, patent free, an idea for automatic Antartic weather stations that will not get buried by snow.
The base of the station is a central disc and a concentric ring, both will be aerodynamicly profiled, so as to not trap snow, as will the sensor and electronic package and solar cell on top of the tower.
Each, central disc and concentric ring, will be capable of supporting the weight of the weather station on loose snow, so they will need to be fairly large. The weather station tower is supported on both of these, the central disc and the concentric ring, with pneumatic rams. The pneumatic reservoir could also be used as an energy storage device for the electronics.
Initially, the concentric ring may support the station and the disc would be elevated above the surface. When snow build-up covered the concentric ring and threatend the disc, the disc would be pushed down to contact the snow and then the concentric ring elevated. The process is then reversed when the central disc starts becoming buried.
If the area has a regular known snow build-up rate, then a simple timer could control operation, say once every 3 months. Otherwise, snow level detectors could be implemented in the tower, pointing down.
Further instrumentation for control purposes may include tilt meter and GPS.
BTW Does anyone have information on the actual effect of the repeated snow burials on the temperature records?
IMO, the eduation system is responsible for creating a couple of generations of folks who are not critical thinkers/problem solvers. They have been taught to read a textbook, memorize the content and choose the right answer from a list when tested. It’s easy to see how this becomes read a peer reviewed paper, memorize the content, choose the conclusion as the right answer … It’s quite easy to herd this kind of thinking by having just a couple of research papers influence everything else that follows.
In a recent article “kitchen experiments” were discussed . I’m not at all surprised that this went right over many heads. It’s not in a book. Not too surprising that in response to these real life examples we got references to more papers.
In many ways we can’t blame these folks for the way they think. That is how they were taught. Unfortunately, this allows a small number of people to influence an entire branch of science.
Ever wonder why a large percentage of skeptics are older? We were taught how to think things through. To get the answer we had to work it out from scratch. That hasn’t been a key part of our educational system. In fact, I suspect you’ll find most of the younger people who are skeptics were actually forced to think things through at some point. However, that number is exceedingly small.
No wonder Al Gore is telling kids to quit listening to older people.
Something to think about …
I watched the Holy, er History Channel (or Discovery, don’t remember which, might have even been Mil Channel) on that. Very interesting.
The CA thread contains several of my comments, and a request which may get a better response here. I am looking for better specifics on station mechanical and electrical design and construction than I seem to be able to find on the U of Wisc site or the references contained there. And, some new inquiries: What kind of battery works reliably at those temperatures? And, how does the solar panel work in the total darkness of Antarctic winter? Maybe the anemometer also drives a generator which charges the battery? While the sun goes away for a few weeks, the wind seems to never really stop. The fact that any data is gathered under these conditions is amazing.
They need a barbecue to keep the snow away. Works everywhere else. Right?
Can I just explain that when, in the past, I have speculated that too many of the Global Warmmongers started off as just woefully inept fifth-rate physicists, and only slowly became dishonest, I didn’t mean to imply that they stopped being woefully inept too.
Gary A. (16:45:09) :
“It looks to me like solar panels are lower than the temp sensors. This would seem to indicate that the stations would quite broadcasting before the temperature sensors go below the snow (looks like 6″ to 12″ above the solar panel). Of course the height of the sensors above the snow will decrease from 6′ or so as the snow “buries” the station.”
Maybe not. There must be battery packs for the electrical system, I think that there are a lot of cloudy days down there. They may hold enough charge to operate for weeks, maybe months. I doubt these batteries are much of a source of heat, though, with regards to whether buried sensors would be getting heat from them. Heat reflecting off snow when the sensor is above snow level would likely be a bigger issue, and more the closer the sensor is to the snow level.