From the British Antarctic Survey
New climate history adds to understanding of recent Antarctic Peninsula warming
Results published this week by a team of polar scientists from Britain, Australia and France adds a new dimension to our understanding of Antarctic Peninsula climate change and the likely causes of the break-up of its ice shelves.
The first comprehensive reconstruction of a 15,000 year climate history from an ice core collected from James Ross Island in the Antarctic Peninsula region is reported this week in the journal Nature. The scientists reveal that the rapid warming of this region over the last 100 -years has been unprecedented and came on top of a slower natural climate warming that began around 600 years ago. These centuries of continual warming meant that by the time the unusual recent warming began, the Antarctic Peninsula ice shelves were already poised for the dramatic break-ups observed from the 1990’s onwards.
The Antarctic Peninsula is one of the fastest warming places on Earth – average temperatures from meteorological stations near James Ross Island have risen by nearly 2°C in the past 50 years.
Lead author Dr Robert Mulvaney OBE, from British Antarctic Survey (BAS) says,
“This is a really interesting result. One of the key questions that scientists are attempting to answer is how much of the Earth’s recently observed warming is due to natural climate variation and how much can be attributed to human activity since the industrial revolution. The only way we can do this is by looking back through time when the Earth experienced ice ages and warm periods, and ice cores are a very good method for doing this.”
Dr Mulvaney continues,
“We know that something unusual is happening in the Antarctic Peninsula. To find out more we mounted a scientific expedition to collect an ice core from James Ross Island – on the northernmost tip of the Peninsula. Within the 364m long core are layers of snow that fell every year for the last 50,000 years. Sophisticated chemical analysis – at BAS and the NERC Isotope Geosciences Laboratory (part of British Geological Survey) – was used to re-create a temperature record over this period.
“For this study we looked in detail at the last 15,000 years – from the time when the Earth emerged from the last ice age and entered into the current warm period. What we see in the ice core temperature record is that the Antarctic Peninsula warmed by about 6°C as it emerged from the last ice age. By 11,000 years ago the temperature had risen to about 1.3°C warmer than today’s average and other research indicates that the Antarctic Peninsula ice sheet was shrinking at this time and some of the surrounding ice shelves retreated. The local climate then cooled in two stages, reaching a minimum about 600 years ago. The ice shelves on the northern Antarctic Peninsula expanded during this cooling. Approximately 600 years ago the local temperature started to warm again, followed by a more rapid warming in the last 50-100 years that coincides with present-day disintegration of ice shelves and glacier retreat.”
Co-Author Dr Nerilie Abram formerly from British Antarctic Survey and now with the Research School of Earth Sciences, at The Australian National University says,
“The centuries of ongoing warming have meant that marginal ice shelves on the northern Peninsula were poised for the succession of collapses that we have witnessed over the last two decades. And if this rapid warming that we are now seeing continues, we can expect that ice shelves further south along the Peninsula that have been stable for thousands of years will also become vulnerable.”
Olivier Alemany, from the French Laboratoire de Glaciologie et Géophysique de l’Environnement was part of the expedition. He says,
“The international polar science community has collected and analysed ice cores from Antarctica and Greenland as part of an effort to reconstruct the Earth’s past climate and atmosphere. Our team wanted to understand how the recent warming and the loss of ice shelves compared to the longer term climate trends in the region.”
This research makes a significant contribution to the understanding of the role that Antarctica’s ice sheets play in influencing future climate and sea-level rise. It was funded by NERC (Natural Environment Research Council).
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Regarding that rapid warming of 2C in the last 50 years, just remember that most weather stations in the Antarctic are near humanity, and humanity requires warmth to survive. For example:
The Antarctic peninsula is the most populated place in Antarctica.
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Anthony, Ian reported earlier in the thread that the thermometers housed near camps were used for local weather only, as information for pilots and how many layers of thermal underwear to don. The temperatures measurements used for climate information are automated and “use the ARGOS data relay system, carried by the NOAA series of near-polar orbiting satellites.” negating the need for what you suggest. Im sure Ian from above would have some excellent info for you given his position within the Australian Antarctic Division. Your photo does not support in any way what you are suggesting. Have attached a link to a good site that includes a link to a page that discusses the known possible problems with the types of thermometers and sensors used in Antactica. It hasn’t been updated for some time so you may have something to contribute/ some issues may have been resolved in further study. In any case creating a dialogue with Ian may be helpful as I don’t understand why you keep referencing that photo and hypothesising about poorly sited stations when an on the ground first hand scientist tells us that they are not even used for climate related data.
REPLY: “The temperatures measurements used for climate information are automated and “use the ARGOS data relay system, carried by the NOAA series of near-polar orbiting satellites.” negating the need for what you suggest. ”
Ummm, no. Argos didn’t come into being till the mid 2000’s, and nearly all climate data before that back to the first camps in Antarctica came from Stevenson Screen type stations. While there may have been some near term improvements the fact the the stations for decades prior were near human habitation because they were required to be manually read. For example: http://www.discoveringantarctica.org.uk/alevel_2_1.html
And one of the oldest ones: http://www.nhm.ac.uk/nature-online/earth/antarctica/antarctic-conservation/blog-archive/image.php?src=http://www.nhm.ac.uk/resources/nature-online/earth/antarctica/blog-archive/images/meteorological-screen-545.jpg&from=/nature-online/earth/antarctica/blog-archive/?cat=14&paged=8
Meteorological screen used by Captain Scott’s expedition nearly a century ago – it stands about 65m behind the expedition base at Cape Evans and would have been used to capture some of the earliest information on weather on the continent.
And here’s a stamp showing a Stevenson Screen station in Antarctica: http://rammb.cira.colostate.edu/dev/hillger/BritishAntarctic.319.jpg
Here’s one from 1935: http://www.freezeframe.ac.uk/collection/british-graham-land-expedition-collection/p51-8-a094
Here’s the longest record in Antarctica, at Mawson: http://www.antarctica.gov.au/living-and-working/stations/mawson/this-week-at-mawson/2011/this-week-at-mawson-21-october-2011
Still a screen there. Still inside the camp.
Many of the newer automated stations have their own problems, such as getting buried by snow, which makes them report warmer temperatures. Sorry, you kids just don’t know what you are talking about. – Anthony
Anthony – I think you are confusing ARGO (robotic ocean buoys that measure temperature and salinity at depth) with ARGOS (satellite based data relay system). ARGOS has been around since at least the early 1980s: large scale ARGO deployments only really started in the early 2000s.
Most Automatic Weather Stations (AWS) in Antarctica use the ARGOS data relay system – since the satellites are near-polar orbiters, you gets lots of passes at high latitude and almost hourly measurements. Yes – snow accumulation does alter the height of the AWS surface above the surface if the stations are not maintained. But because of the persistent and strong surface temperature inversion over the ice sheet, this means that the measured temperatures get COLDER (not warner) as they get closer to the surface. (I question who does and who does not know what they are talking about).
The AWS are almost all in very remote sites (hundreds of kilometres from heated buildings). The record from AWS does only extend back about 30 years, and manned stations or proxies (ice cores, etc) are needed for longer records. But over the last 30 years or so, the trends from the AWS and the manned stations are consistent.
Ian is correct Anthony. ARGOS has been used in Antarctica since 1984. Your assertion that any measurements before 2000 were taken using Stevenson Screens is incorrect. A very quick google will tell you that.
REPLY: Then show it. Don’t make me do your work for you. – Anthony
http://aws.acecrc.org.au/background.html ……..to add to above
REPLY: So? It doesn’t prove your point. See below. – Anthony
Yes I’m familiar with the AWS stations in Antarctica, but neither Ian nor Kermode said AWS, you said ARGOS. Best to be precise first with your terminology to prevent confusion. I thought you were speaking of the satellite system used for the ARGOS buoys.
This still does change the fact that many Stevenson screens (such as the one that is shown in Mawson) are converted for such automated purposes and still in the camp. Rule 1 of stations is not to move them if you can help it. The CLIMAT reports, ( http://en.wikipedia.org/wiki/CLIMAT) which are used in GHCN, GISS, HadCRUT and other climate databases, clearly show such stations like Mawson and Rothera point (also shown above) in the report: http://www.ogimet.com/cgi-bin/gclimat?lang=en&mode=1&state=Anta&ind=&ord=REV&verb=no&year=2012&mes=07&months=
The AWS stations have their own problems, they tend to get buried, creating false high temperature readings due to the snow. See: http://wattsupwiththat.com/2009/02/04/snow-job-in-antarctica-digging-out-the-data-source/
Note the Fossil Bluff station, right next to a building, also in the CLIMAT report.
The issue is stations be right next to growing human influence in the Antarctic peninsula over the last century. Some data relay doesn’t change that, especially when the CLIMAT reports show those base stations and a few of the network of AWS stations (but not all), such as the network managed by University of Wisconsin. While there are a handful of AWS stations in the CLIMAT report, the majority are at base camps and it has always been that way because they have the longest baseline for climate.
Here’s a map of the AWS stations, many in the peninsula are warming:
The peninsula has the greatest population, it also is the most affected by changes in maritime currents. Note that not all of the AWS stations shown on the map are in the CLIMAT report.
As for who knows what about snow and warmth, ask the subniveans.
The fact remains – manual weather stations were established near camps, camps have grown over time, and they continue to be used for climate databases, even though they may have been automated. AWS stations are mostly used for independent scientific research, but except for a few listed, aren’t part of the CLIMAT reports. They also don’t have the long term history.
In another polar envirnment, see how even a village like Barrow has issues with waste heat http://onlinelibrary.wiley.com/doi/10.1002/joc.971/abstract
http://www.cas.umt.edu/geography/documents/Hinkel_etal_2003_winter_UHI.pdf
Sorry, not buying your arguments.
Thanks for the long reply Anthony but at the start you say we didnt mention AWS…….from Ian previously….
“Most Automatic Weather Stations (AWS) in Antarctica use the ARGOS data relay system”
I said “are automated and use the ARGOS data relay system.
Ians comment mentions AWS and both are very specific that it is the data relay system not a plural of the ARGO system. Please read things more carefully to avoid confusion.
I don’t see every comment that gets posted on this blog we have a team of moderators so I never saw the original I only saw yours
Shelama says:
August 27, 2012 at 10:55 am
Anthony, your credibility remains unchanged with me.
With me as well!
This is what has happened since I last looked at these comments?
The people who gladly accept the physics of longwave infrared when talking about the radiative properties of greenhouse gases operating many kilometers above their heads, and call all skeptics “anti-science deniers” when a few out-there ones don’t,
Can’t accept those physics over much-shorter distances of several tens of meters, and make snide insults about Anthony Watts’ credibility.
And they say we are the ones who refuse to accept “Inconvenient Truths”? And wonder why people don’t accept their doubletalk?
The photo is not of Mawson Station. It is a temporary traverse station. The sole purpose of the weather station is to determine what the weather is like before venturing outside.
Simon says (Ha, good one!) on August 29, 2012 at 12:58 am:
A. Show where it was stated the Stevenson screen pictured on the 1997 Australian Antarctic Territory first day cover featuring the Apple huts was at Mawson Station, as you are implying was stated.
B. Why go to all that trouble to set up such a scientific instrument to just make a quick check of outside conditions? There are no day/night 24-hr variations in temperature, it’d basically be what it was the day before. Precipitation is practically nonexistent. The only real thing worth checking would be wind speed, and that Stevenson screen sure ain’t housing an anemometer.
That setup is for scientific temperature measurements, and that’s all. If all they needed to know was the temperature on the other side of the door, there are far simpler alternatives that can be setup far faster, even built into the huts. Your statement fails the practicality, reasonableness, and logic tests.
Kadaka,
You need to read the upthread comments. A scientist who lived in the hut nearest the screen said the temperature was measured for the purpose of determining what clothes to wear when they left the hut. Your comment fails the informed comment test. Pay attention to what other people tell you to prevent lapses like this from happening.
kadaka (KD Knoebel) says: (August 29, 2012 at 12:01 am )
“….And they say we are the ones who refuse to accept “Inconvenient Truths”? And wonder why people don’t accept their doubletalk?…”
As Michael Sweet has pointed out your error kadaka, here is a chance to redeem yourself and demonstrate that you have some integrity. But then, if you had actually read the previous comments before making your post, you wouldn’t have made the error would you.
So how about it? Going to admit you are wrong?
Michael Sweet says:
“A scientist who lived in the hut nearest the screen said the temperature was measured for the purpose of determining what clothes to wear when they left the hut.”
Yes. But. That is not the purpose for which the station was built. Is it?
The picture here gives a better idea of the proximity of the weather station to the unheated huts.
Even if the station was used for long-term records, which apparently it hasn’t been, not to mention it is not situated on the peninsula…
It would be easy enough to adjust for the step change if in fact there was any extra heat affecting it from the huts.
You can see pictures of the actual AWS weather stations in the Antarcic Peninsula at the following link.
http://amrc.ssec.wisc.edu/aws/index.php?region=Antarctic%20Peninsula&station=Bonaparte%20Point&year=2012
No nearby buildings evident.