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.
Simon Evans (17:06:33) :
“I simply don’t know, but I certainly don’t see why the snow issue necessarily implies a warming bias over time.”
Elementary – snow is an insulator. When caught in a blizzard, dig a snow cave to survive.
Also from Simon:
“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. ”
Since the Harry data is basic to the Steig paper – and the Harry data is corrupted, then the Steig paper is automatically corrupted. If the paper is reqworked with the correct data then it becomes rehabilitated (sorta). But until then, the results are scientifically and logically void.
Also from Simon:
“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.”
Evidently there is a continuing issue with Antarctic records. If nothing else, interpolation of satellite data between stations is a questionable technique. But there’s also the question of data continuity and quality. Bad data, “correct results” = Bad Science.
According to Steig (over at RC), the automated weather stations (the ones that have the snow burial issues) were not used in the temp reconstruction, so most of this discussion is moot.
And while burial might effect the absolute temperatures recorded by the automated stations, it is not clear to me how that would necessarily bias the temperature TREND upward- unless the length of time the stations are spending buried is increasing.
And it is certainly possible for snow burial to introduce a cooling bias. Most snow falls during Antarctica’s winter. The stations probably don’t get dug out until the spring (not much outdoor field work goes on during the Antarctic winter). So the stations stay buried in the cold winter snows until they are dug out during warmer weather.
The insulative properties of snow work both ways- it also keeps the cold winter snow that buried the station from warming up as surface air temperatures rise in the spring.
So there is no reason to assume that any bias (if there is any) in the temperature trend from the automated stations is towards warming.
REPLY: See the update imagery at the top, looks like the Stevenson Screen is fairly close to the only heat sources around. – Anthony
Ric Werme.
I understand your frustration but as I understand it, Steve McIntire tried to get co-operation & failed. That is in my belief unfortunate as it creates ‘sides’.
Just releasing data & methods would either substantiate or deny the claims. Hiding of both makes suspicion.
How, (effectively,) public employees can claim intellectual property rights, I have yet to ascertain.
DaveE.
What would this station be ranked for quality? I read this at CA, good stuff. It’s amazing to see the stations get buried like that. Being from Michigan, I can imagine digging out that kind of instrument in that cold.
I’ve been trying to get code and data from Eric Steig who oddly claims his code has been archived.
http://noconsensus.wordpress.com/2009/02/05/steigs-code/
The team has lost their mind lately.
Forgot to mention.
Remember the 2-3ºC “uncertainty”!
That’s not an offset but an error band in the satellite surface readings.
They’ve not got the surface readings sorted yet, so how do you get a precision of 0.1ºC?
DaveE.
George E. Smith (16:41:08) :
I’m afraid I have to vote for Phil still. (And not just because HP laid me of a couple years ago. Very good timing actually, so no complaints. Well, about that. There are other reasons why I bought a Lexmark laser printer last week.)
Sure, the dry ice is getting banged around by lots of molecules, but that means fairly little – unless there is enough CO2 vapor, less CO2 will freeze than is evaporating. Two analogies:
Not a good analogy, but recall recent discussions about hot things and cold things both radiating and hot things absorbing photons from cold things but still cooling. The warm things still cool because they radiate more than the cold.
Better analogy, consider dew formation. Dew only forms when the ground temp is cold enough so that air is being chilled to less than the dewpoint. The partial pressure of H2O is not one atmosphere, it is well less than that. However, the air is saturated and the partial pressure of H2O follows the H2O phase diagram. (The same with frost, but you don’t see much frost, and I’d feel compelled to talk about frost point vs dew point. I show both at http://home.comcast.net/~ewerme/wx/current.htm .) If your description were right, dew would form whenever there is water vapor and an air temp of less than 100C.
When I head into work lately, one of my tasks is to clear my windshield. Some days it has snow this time of year, some days it has frost, some days it’s clear. Some days the air temp is 30F (not this year!) and there might be frost, some days the air temp is 0F and their might be frost. The frost depends pretty much solely on the dew point and the partial pressure of H2O vapor in the area.
So, in the CO2 phase diagram at http://scifun.chem.wisc.edu/chemweek/CO2/CO2_phase_diagram.gif we’re running off the edge. In the lower left corner, suppose the partial pressure of CO2 were 0.001 atm. That’s 1000 ppm, about 3X the current level. Equilibrium would be around -135C. Dry ice would evaporate above that temperature, and grow below that temperature.
You’re not a total idiot, but perhaps your biggest mistake was to believe a PhD physicist. 20 minutes timeout at RealClimate for you! That or move to New Hampshire and learn what RealWeather is all about. 🙂
I wonder what that person was walking on. Perhaps frost that forms at Antarctic temps is different than the types frost most people get to see. About the only thing more interesting than liquid water is frozen water.
“Pamela Gray (17:14:43) :
They need a barbecue to keep the snow away. Works everywhere else. Right?”
Ok. That was funny.
Thanks for the chuckle!
JimB
“MattN (17:29:25) :
The next question I have is, will Stieg correct this error?
Will Nature make a retraction?”
Posts on RC indicate that this data error has no impact on the conclusions reached in the paper.
JimB
that’s the best place to never work
The screen at BAS fossil Bluff is perfectly positioned to experience the plume downwash from the heating flues. Winds about 2 -3m/sec or more trap the plume in behind the building wake (cavity zone), with the resulting increase in ambient temperature in the building cavity zone. Plume Dispersion 101. I would certainly not trust the data from that location.
Ok…how is the idea of a warming trend in antarctica where instruments have become buried in snow NOT funny?
JimB
Jeff Id (18:44:18) :
Unless I’m missing something, you missed the comment 160 just before the link I posted:
Gavin’s link looks like it goes to data, though I didn’t go beyond that page.
I don’t understand his rant about archiving data, there are 30 year-old source archiving systems that GISS doesn’t use and more modern ones that work just fine over the Internet. I’m sure there are plenty of students at Columbia and Washington who use them today and could set them up for “the team” in to time at all.
I’d volunteer to go to Antarctica and do a site audit for A’s project, but funding is hard to come by . . .
Or i could drive to Mesa, AZ and help out.
Tough decision . . .
H
Jeff Id (18:44:18) :
I’ve been trying to get code and data from Eric Steig who oddly claims his code has been archived.
Oh – I understand, data is available, RegEm is available, actual code for analysis is not. That seems rather rude.
See the update imagery at the top, looks like the Stevenson Screen is fairly close to the only heat sources around. – Anthony
But how does burial affect the temperature trend? I would think that the automated stations have had the burial issues since they where initially set up. So that wouldn’t bias the temperature trend unless the time they spend buried has changed through time- and that could be either a warming or cooling bias.
I wonder if Hansen is quietly chuckling at the mess his detractors, Gavin and Steig, have found themselves in?
Robert Wood (17:08:36) :
Great post Anthony.
‘I hereby give to humanity, patent free, an idea for automatic Antartic weather stations that will not get buried by snow’.
Robert,
Can you send me a sketch or a drawing.
I will build a prototype for testing.
Oh, great. A commemorative stamp with a badly sited CRS!
The irony!
Pamela Gray (18:10:40) :
“Richard, you beat me to it. I was just going to say that buried temperature sensors HAS to be the fault of school teachers. HAS to be!”
I would never blame the teachers. They can only work with what they are given. I know many teachers that disliked the “system” as much as anyone.
Anthony,
I noticed that you show the Stevenson screen next to the heated hut partially hidden by the snow bank.
If I’m not mistaken that snow bank is actually the snow that must be repeatedly removed from around those heated buildings. It seems that the deeper that this artificial valley becomes, there would be some greater effect on the thermometers. In which direction, I don’t have a clue.
Mike Bryant
Ric Werme (19:18:17) :
Bingo, now how does he claim openness?
My first guess is that his paper is correct. Lack of information makes me wonder why not? I mean come on, if the Antarctic is warming let’s see, I want to know. We already know the rest of the world warmed so no loss there.
He obviously has the code all together on an easily accessible file set. His coauthor Mann actually did a pretty good job of disclosure in his 08 paper.
OT but good
The snake’s enormous dimensions are a sign that temperatures along the equator where the remains were found were once much balmier. (hotter)
“The bigger you get, the more energy you need overall,” Head said. “And since they get their energy from external environments, the bigger they are, the more energy they’re going to require from the external environment.”
(Snakes are cold-blooded animals, so they don’t generate their own body heat.)
The researchers calculated that in order to support the slithering giant, its tropical habitat would have needed a temperature of about 86 to 93 degrees Fahrenheit (30 to 34 degrees Celsius).
“Tropical ecosystems of South America were surprisingly different 60 million years ago,” said Jonathan Bloch, a vertebrate paleontologist at the University of Florida, Florida Museum of Natural History, who worked with Head on the snake study. “It was a rain forest, like today, but it was even hotter and the cold-blooded reptiles were all substantially larger. The result was, among other things, the largest snakes the world has ever seen … and hopefully ever will.”
link:
http://www.foxnews.com/story/0,2933,487885,00.html
Does it worry anyone else that satellites are now going to be recording the temperatures and CO2 output? There will come a day when only a select few will have official, government approved access to weather and carbon dioxide data. In the not too distant future, I believe that weather stations will be considered obsolete and land based data will be publicly scoffed at by the likes of James Hansen and Al Gore. These are dangerous times.
I thought Steve didn’t have a problem with your title? Perhaps you can post about his censorship, as that is a topic you’ve shown an interest in when it comes to the “alarmists”…
Richard, I am a teacher with three degrees and published research. I don’t just work with what I’m given. You seem to have a low opinion of a teacher’s ability to think and reason. What “system” are you talking about if not the teachers?