Sunday, July 15, 2007

Vacation time

Sea, sand and sun: what better way is there to disconnect from the ice-filled world of Antarctica? I am leaving to go on vacation today, and will be back in a few short weeks. Posting will probably be irregular while I am away, however, I will try to keep as up to date as possible.

Best summer (boreal summer) wishes to all my readers, be you at work or in the process of enjoying a few days' break. I will be back soon, my batteries charged by liberal applications of solar energy and salt water, ready to pick up where I left off.

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Thursday, July 12, 2007

A seismologist's view of thermodynamics

Since when have seismologists been interested in thermodynamics? Personally speaking, thermodynamics was one of my least favorite subjects at university. In the past few days, however, it has become necessary for me to look into it again.

Here is the problem: how to keep our seismic stations running for as long as possible after the sun goes down for the Antarctic winter, when the only power available comes from pure-lead batteries? The colder the batteries get, the less power they can supply. So the problem becomes: how can we keep the batteries warm for as long as possible?

While the sun is up, we can generate power using solar panels, so we can use some of this power to heat the enclosure in which we house the batteries. The amount of energy we dissipate as heat within the enclosure and its degree of insulation will determine the temperature we will be able to maintain the batteries at.

At sundown, we will no longer be able to actively heat the enclosures, so they will start to cool down. The temperature will fall exponentially, until it reaches the outside temperature, approximately -60C, at which the batteries are essentially dead. The rate of the exponential decay depends on the enclosure insulation, but also on the heat capacity of its contents. The batteries themselves will contribute to this heat capacity, slowing down the cooling significantly.

We still need to run some control experiments, but it seems that a combination of good insulation and the heat capacity of the batteries may allow us to keep recording for a non-negligible part of the Antarctic winter.



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Wednesday, July 11, 2007

Historical seismometers #1 - Wiechert

Modern seismometers are all well and good - in fact most are excellent - but they are not as fascinating as historical instruments. The institute I work at in Strasbourg runs a Seismology Museum that contains a superb collection of seismometers. In this series of posts, I'll be showcasing my favorite ones.


First up, the Wiechert horizontal seismometer, shown in the figure above [photo credit Michel Dufloux]. It is an entirely mechanical seismometer, made in Gottingen (Germany) in 1904, and was in use in the Strasbourg seismic observatory between 1904 and 1968.

It is essentially an inverted pendulum, which records both components of horizontal motion on rolls of smoked paper. It weighs 1000 kg, and has a natural period of 8 seconds. Damping is provided by two air-pistons on the top of the instrument. The pendulum is centered by placing a series of small weights on top of the main mass. This instrument is very delicate to set up and use, but it is truly a work of art.

The Wiechert in Strasbourg is no longer in operation, but is visible in our museum. However, the Wiechert Earthquake Station in Gottingen, which is open to the public, does have a working instrument.

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Antarctic Sea Ice Video

Antarctica is covered in land-ice, and surrounded by a skirt of sea-ice. This latter is not stable, but grows, shrinks and moves throughout the year.

The following is a video published by SCAR (Scientific Committee for Antarctic Research). It shows two full cycles of Antarctic sea-ice growth, compiled from satellite observations.

Antarctic Sea Ice 1994-1995

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Tuesday, July 10, 2007

Expedition planning #3 - The purchasing jigsaw

Seismic experiments require seismic stations, which don't exactly come cheap. You would think that once funding has been secured, the rest would be easy. Read on to find out how purchasing anything in a university context is like doing a jigsaw puzzle.

Once the funding is approved, it has to be made accessible, i.e. put into a university spending account which you can order from. At this stage, you often have to pre-decide how much of this money will be used for "investment" (i.e. for purchasing items which cost more than a certain amount and which have to be inventoried), and how much will be used for running costs. You had better get this part right, because university accountants will most likely refuse to change anything once it's been decided.

The next step is publishing a public Equipment Search, in which you state what it is you would like to purchase, and give the criteria on which you will judge offers made to you by the various companies which make or distribute the equipment you are searching for. Once the search is officially over, you must chose one of the competing bids, and justify your choice using the criteria you published in the search itself.

Then you can have a purchase order made out by the university. This requires the presence of a person qualified to draw up the order (this is not left to scientists - oh no!), and of the person who is responsible for the university account being used to make the purchase (which is often a senior scientist). Of course, the probability of both of these people being present at the same time (or at least soon after one another) is a function of the distribution of public holidays, and the of tendency of people to go on vacation. This latter factor is the most important one during the months of July and August.

Then, finally, you can send off the purchase order, arrange for shipping to a customs broker, and arrange for the customs broker to deliver when the university will be open again after the holidays. You hope, of course, that delivery will be made in time for you to test the equipment you have purchased before sending it on to the underside of the world for your crazy seismic experiment in Antarctica.

If you think this is more than enough to give you a head-ache, you are not alone! Maybe once I'll have done this a few more times it will all seem easier. For the moment, it's not fun at all...

[Image credits: Weston Boyd]
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Monday, July 9, 2007

McMurdo Blue Moon Run

To continue the series of crazy things done on Antarctic bases, Chris Calnan on the Antarctic Conservation Blog tells the story of The Blue Moon Run, a run of around 2.5 kilometers from McMurdo to Discovery Hut and back. About half of the over-winter team at McMurdo participated took part, some running, others walking.

A two and a half km run at -33 degrees C - not really my idea of fun!

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Sunday, July 8, 2007

CASE-IPY - Scientific Project

CASE-IPY : Concordia Antarctic Seismic Experiment for the International Polar Year

The CASE-IPY project is a part of a larger IPY initiative, the Polar Earth Observing Network (POLENET), which includes contributions from 24 countries, including France, Italy, Australia and the United States.

The aim of the POLENET consortium is to investigate polar geodynamics, the earth’s magnetic field, crust, mantle and core structure and dynamics, and systems-scale interactions of the solid earth, the cryosphere, the oceans and the atmosphere. Activities will be focused on deployment of autonomous observatories at remote sites on the continents and offshore, coordinated with measurements made at permanent station observatories.

We propose deploying 10 broad-band seismometers in East Antarctica, using Concordia / Dome C as our starting point. Our deployment will be coordinated with those of our Italian, American and Australian colleagues in order to achieve maximum coverage of the East Antarctica Plateau, and to share a maximum of logistical support.


Proposed IPY deployments in East Antarctica. Red: CASE-IPY. Dark blue: USA. Dark green: Australia. Light green: Italy (INGV). Light blue (small symbols): TAMSEIS (previously deployed by USA).

Our deployment will cover a part of East Antarctica that has as yet never been the subject of investigation, and will be a fully functional seismic antenna in its own right. It will also complete and connect the American, Australian and Italian deployments, thereby helping to create a single, large-footprint seismic array which will cover a substantial portion of the continent.

This combined POLENET East Antarctica network will number some 55 stations, and will have a combined length of over 4000 km, with a significant 2D component, providing unprecedented coverage of East Antarctica, and allowing us to reach the following objectives:
  1. improve our knowledge of the regional crustal structure;
  2. improve our knowledge of the regional lithospheric structure;
  3. improve our sampling for inner core studies.

You can read more about the project on the IPY Expression of Intent database, which you can reach from this post: Concordia Antarctic Seismic Experiment - International Polar Year.

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Friday, July 6, 2007

IPY news : CASE-IPY is selected !!!

Our International Polar Year project has just been selected by the ANR (Agence National de la Recherche)!! In short, this means the CASE-IPY project has passed scientific scrutiny, and is deemed worth of funding. Phew....!!!!

We have been waiting a long time for this news (ever since the application deadline, which was March 1st - four months ago). My first reaction upon hearing the news this morning was elation: "We made it!". The second was: "Oh my God we are actually going to have to run this crazy experiment..." Still, even that thought is no way near enough to wipe the grin off my face.

Now for the dampener: although the project selection phase is now over, we still do not know what the funding decision itself will be. The ANR conditions funding of selected projects on the validation of each project's budget, on their financial analysis of our partners, and on the transmission of all necessary administrative and financial information by each of the partners.

In short: today's news means we should be funded, but we don't yet know by how much.



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Tuesday, July 3, 2007

Featured organizations #1 : GeoHazards International


GeoHazards International is a Non Governmental Organization (NGO) with a mission:

To reduce death and suffering - particularly among children - due to earthquakes and other natural hazards in the world's most vulnerable communities through advocacy, preparedness, prevention and mitigation.

This mission is entirely independent of political, business, religious or research agendas. It is achieved through a combination of international assistance and local responsibility. Recognition of risk and of the methods used to manage it, are central to the way GHI helps vulnerable communities reduce death and injury. Communities are made safer because GHI

  1. raises awareness of risk;
  2. builds local institutions to manage that risk;
  3. strengthens schools, thereby protecting and training the communities' future generations.
GHI is managed by a small Board of Trustees, which includes specialists in earthquake and natural hazards. Technical guidance is provided by a group of international experts in the earthquake risk of developing countries, that form GHI's Board of Advisors. Day-to-day operations are performed by a small group of GHI Staff, who are based in Palo Alto, California.

Despite such a small team, the GeoHazards International has successfully run a number of hazard-mitigation projects. They are currently running projects in
Delhi (Earthquake Safety Initiative for Lifeline Buildings) and Dharamsala (both are in India).

GHI invite all people committed to helping reduce death and injury due to earthquakes in the world's most vulnerable communities to become a member of their organization.

For the whole month of July 2007, you can also contribute to GHI by voting for them on the Educated Earth donation poll.


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Monday, July 2, 2007

Midwinter: a great post from Halley

Midwinter has come and gone. The sun is slowly making its way back to that place on the horizon from which it will burst forth again, ending the long and cold Antarctic night. Slowly, as the aftermath of the festivities wears off, stories about Midwinter fun and games start making their way into the blogosphere.

One of these stories comes to us from Halley, courtesy of their Comms manager. A Midwinter Celebration tells of the various fun activities being run during the weeks before and after their grand Midwinter banquet. One of these activities is the preparing of "Christmas presents". Each member of the winter-over team has to make (emphasis on make, not buy!) a present for one other team member. These gifts are to be presented at Midwinter... Read the original post (linked above) to find out more!

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Sunday, July 1, 2007

Antarctica : Top 10 videos

How to tell the story of Antarctica? Some use words, others images, yet others videos. Here is my Top 10 selection of videos depicting Antarctica (descriptions are those of the original video postings):

  1. Antarctica Time Lapse: A Year on Ice - Time-lapse video filmed in Antarctica, in and around McMurdo Station and Scott Base.
  2. Antarctique - En suivant les traces... - Winner of the prize "GLACON D'OR 2007" at the NUITS POLAIRES amateur film competition (Paris le 18 février 2007).
  3. Antarctica Condition 1 Weather - Filmed at McMurdo Station, where it is relatively sheltered by the surrounding hills. The weather down here is classified as being Condition 3 (nice weather), Condition 2 (not so nice), or Condition 1...
  4. Aurora Australis - The Southern Lights - Time-lapse footage of the Aurora Australis, or Southern Lights. This is the Southern Hemisphere equivalent of the Aurora Borealis or Northern Lights.
  5. Volomania - An extract from the film "Antartide 2002", depicting an adventurous trip on the Antarctic Peninsula.
  6. Antarctica in 5 minutes - From Elephant Island to the Antarctic Circle.
  7. Antarctica: A Flying Tour of the Frozen Continent - Narrated tour of Antarctica through the eyes of RADARSAT. Credits: NASA Goddard Scientific Visualzation Laboratory.
  8. Dive Antarctica - Summary video of Dive Antarctica trip 2006
  9. Diving Under the Ice - The Exploratorium's Mary Miller dives under the ice in Antarctica!
  10. South Pole Station Tour - Visit Antarctica with a guided tour of the Amundsen-Scott South Pole Station, directed by researchers working on the South Pole Telescope


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