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The Polar Museum: news blog

Posts Tagged ‘science’

Sounding out the Antarctic

Wednesday, November 23rd, 2016

This blog post was written by Grace Atkinson, a local student who came to see us in the Museum and asked if there was anything she could do. We gave her a research project, and this blog post is the outcome.

As an International Baccalaureate student with a keen interest in both geography and the Antarctic I decided to contact the Polar Museum to see if there was a project I could do outside of my studies to enhance my geographical knowledge as I am planning to study Geography at University. After looking at the exhibits I thought a blog post about radio-echo sounding in the Antarctic would be an engaging topic to research.

My aim is to increase people’s awareness of the different techniques used by scientists in the Antarctic to collect data from the ice sheets as the study of ice is becoming increasingly important; its thickness is useful in determining the impacts of climate change. Radio-echo sounding is a geophysical technique which investigates the thickness of glaciers and ice sheets, this becoming crucial within the study of glaciology. Before radio echo sounding was invented by the Scott Polar Research Institute in the 1960s, scientists such as Amory Waite, used radio to measure ice thickness however this method wasn’t widely known. Radar became more popular after an incident involving a WW11 Allied aircraft which when flying across Greenland crashed into the ice due to miscalculations with their radar altimeters. The accident caused increased interest in using the radar for experiments that measure ice sheet thickness in the Arctic.

Oliver Shepard stands on snow holding ice core drill during the Transglobe Expedition 1979-82.

There are lots of ways to study ice. In this picture Oliver Shepard stands on snow holding ice core drill during the Transglobe Expedition 1979-82.

The technique of radio-echo sounding since being developed in the 1960s is now used by a variety of institutes such as the US National Science Foundation to investigate and map the ice covered terrain in the Antarctic. As water and ice are transparent, low frequency electro magnetic waves can be used in the Antarctic to obtain the information and this method is accurate which is why it is used in other scientific investigations, for example marine acoustic sounding. There are echo pulses which penetrate the ice sheets enabling scientists to receive and analyse the data. These pulses are particularly useful for researchers studying the dynamics of ice sheets and their internal ice structure in sub-glacial regions. The radio echo sounding machine has two crucial components, these being the transmitter which sends out the echo pulses, and the receiver which records the strength of waves and the time it takes for waves to bounce back.

Traditional measurements of sea ice thickness are through drill holes which are effective at giving a good overview of ice thickness in extensive areas, however, the use of electromagnetism in radio echo sounding is much more accurate and reliable by comparison. In addition to this, one of the biggest advantages of radio echo sounding in the drilling of holes is its speed.

The invention of radio echo sounding has been influential and the gateway to the development of more recent methods of measuring sea ice thickness, for example the satellite altimetry which relies on the use of a radar pulse. However, there are limitations to the measurements as the laser only collects data in cloud-free conditions.

After researching the use of radio echo sounding in the Antarctic regions I believe it has proven to be the technology of major interest and importance due to its significance in scientific development such as the discovery of subglacial lakes in Antarctica.

Read about some of the work carried out by scientists at SPRI in recent years here.

New Science in the Museum

Wednesday, September 14th, 2016

I mentioned in my original blog post was that I’ve had one or two ideas about how the Museum could better communicate modern Polar science. Well, here’s one of them: revamping the interactive science displays. The Museum currently has three touchscreens explaining modern Polar science, entitled, respectively, Ice, Climate and Science. These were first installed when the museum was redeveloped in 2010 and are now a little out of date as technology and science have moved on a lot in the last few years. There’s plenty of good information, but the whole thing could do with being rethought and revamped to make it clearer and more representative of the current foci of Polar science.

The Museum's current interactive screen setup

The Museum’s current interactive screen setup

This would be a good way of improving the Museum’s modern science offering – the screens are simply html pages, so there’s very little back end to manage – without having to spend a lot of time or money. I’ve come up with a few suggestions for how things could be improved, such as dedicating one screen to providing the background to Polar science, one to remote sensing (satellites and all that jazz) and one to computer modelling (I may be slightly biased there). These last two are essential tools across all aspects of modern science, so it seems sensible to focus on them. This redesign will also give the Museum the opportunity to link in with the scientific research work many of the staff are involved in, which would also greatly help it to better represent recent scientific developments.

Perhaps you can think of some things that you’d really like to see in the museum. If so, drop the team a line at museum@spri.cam.ac.uk or find them on Twitter or Facebook!

Samuel

Old Science in the Museum

Wednesday, August 31st, 2016

I promised in my last blog post to give some details about some of the more unusual or interesting objects I’ve found whilst poring over the Museum’s scientific collection. I mentioned Andrée’s stuffed carrier pigeon previously, but here are four more objects that I think give a good sense of the Museum’s holdings.

First up is an early pocket sun compass used by Captain Sir James Clark Ross on his voyages in both the Arctic and the Antarctic. Ross’s work was crucial in fixing the position of both Magnetic Poles, which allowed great improvements in Polar navigation. Until the shape and contours of Earth’s magnetic field were known, navigation near the Poles had to be carried out using non-magnetic instruments, such as a sun compass, because the difference between true north/south and magnetic north/south was very large at these high latitudes, but of unknown magnitude. Therefore, other solutions were devised, making this compass not only an item of immense historical significance, but also a good demonstration of practical navigation and the difficulties inherent in early Polar exploration.

Ross's sun compass

Ross’s sun compass

Of possibly even greater historical significance is the second item: Amundsen’s reckoning of his position at the South Pole. Scott and his men found this tied to a flag when they arrived five weeks later and thus knew they had been beaten. The text reads:

‘The Norwegian Home Polheim // is situated in 89° 58′ S Lat // SE by E (comp.) 8 miles // 15 Decbr. 1911 // Roald Amundsen’

Amundsen went to a great deal of effort to verify his position and make sure he had actually reached the Pole, sending men out in several directions for several miles, just to be certain they hadn’t got it wrong. This piece of paper is therefore the outcome of some quite precise navigational and cartographic science as well as marking one of humanity’s major exploratory achievements.

Amundsen’s reckoning of his position

Amundsen’s reckoning of his position

The third object symbolises what is perhaps a lesser-known facet of Polar science: geology. Geology was an important element of many early Polar expeditions, with Antarctic fossils and rocks used to support the emerging theory of continental drift and plate tectonics, and remains of interest to this day. Indeed, this particular piece of rock is a specimen of basaltic lava from the 1967 eruption of Deception Island in the South Shetland Islands (just off the west coast of the Antarctic Peninsula). Antarctica might be seen as a frozen continent, but this piece of lava goes to show that it’s alive and kicking!

Deception Island lava

Deception Island lava

The fourth and final object brings us bang up to date. It’s a digital optical module (DOM) from the IceCube Neutrino Observatory. The observatory was completed in 2010 and sits more than a kilometre under the ice sheet at the South Pole, with thousands of DOMs spread over a cubic kilometre of ice. The observatory detects the flashes of light emitted by neutrinos as they interact with normal matter, allowing information about their origin and energy to be extracted. It’s also unexpectedly turned out to be a surprisingly-useful glaciological tool, as it’s allowed scientists to map the movement of deep layers of the ice, which would otherwise be virtually impossible. This particular DOM developed a fault in testing, so wasn’t used, but this remains probably the Museum’s best current example of modern Polar science and of so-called ‘Big Science’.

Digital Optical Module from the IceCube Neutrino Observatory

Digital Optical Module from the IceCube Neutrino Observatory

Samuel Cook, work placement student

Science at the Polar Museum!

Wednesday, August 17th, 2016

I’m an MPhil student at SPRI, hopefully progressing on to a PhD come October, and after realising I was going to have a three-month gap over the summer between the end of the former and the start of the latter, I was anxious to do something vaguely productive for at least a part of it. I therefore spoke to Charlotte, the curator, who it turned out had something in mind for just such an occasion. My academic work focuses on computer modelling of glaciers, which, you may think, has very little to do with a museum. To some extent, you’d be right, but not entirely (and who says you can’t be interested in more than one thing anyway?). What I was being asked to do, using my scientific expertise, was to look through the Polar Museum’s large collection of science-related artefacts, identify strengths and weaknesses, and suggest items that could be added to the collection to fill any obvious gaps, particularly with regards to modern Polar science (see, I said modelling wasn’t entirely irrelevant). This was known to be a bit of a gap in what was, unsurprisingly, a more historically-oriented collection.

Stuffed carrier pigeon from the Andrée balloon expedition to the North Pole

Is it a bird? Is it a plane? Yes, it’s a bird. The Museum’s stuffed carrier pigeon from the fatally-unsuccessful Andrée balloon expedition to the North Pole.

Having spent an inordinate amount of time combing through the Museum’s database, launching exploratory expeditions to the basement and deciding quite what you categorise a stuffed carrier pigeon as (is it natural history? Is it communications technology? Is it a navigational aid?), I’ve managed to get a fair idea of what we have and haven’t already got. As a result of this, I’ll be writing a report for Charlotte outlining the current state of the collection and suggesting what we might want to consider acquiring to strengthen it. One problem that has become obvious is that, with modern Polar science being so based on remote sensing (i.e. using satellites and airborne instruments to gather data) and computer analysis, the actual number of tangible objects related to it is rather smaller than it was a century ago – and most of the ones that do exist are essentially variations on the theme of ‘something that looks like a smartphone’. Given getting an entire satellite isn’t really practical for such a small museum, I’ve had to think a bit more widely about what best represents modern science. I’ve come up with a few ideas, so watch this space to see if any exciting new gizmos make their appearance in the future! Further blog posts will be forthcoming, giving a bit more detail about some of the objects I’ve found and some of my ideas.

Needless to say, it’s been a busy few weeks!

Samuel