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SEAT: Satellite Era Accumulation Traverse: An Airport Boomerang

December 8th, 2011 by Maria-Jose Viñas

By Lora Koenig

On December 5, we boomeranged to and from the airport. Here is a picture of Ludo and Clem in the inside of Ivan the Terra Bus on our way from McMurdo to the airport, Pegasus Field, for our flight to Byrd.

 And here is a picture of Ludo and Clem in the back of a Delta on our way back from the airport to McMurdo.

In the pictures they seem just as happy returning from the airport as they were going, but I think that was just for the camera.

We were all very excited about our flight to Byrd because we were already a week delayed in getting into the deep field. (Camps in the middle of Antarctica, outside of McMurdo Station, are called “the deep field.”) We boarded Ivan just after lunch for the 1 hour and 10 minute ride to Pegasus Field. Once at Pegasus, we were at the passenger terminal of the airport, a triple-wide trailer house that sits on a sled so it can be moved (it also serves as the Galley for airport workers), when we were told that the flight was canceled due to weather at Byrd. We were all a little sad because we want to get to Byrd to start collecting our science data. Our flight was canceled for good reason though; there was less than 100-meter visibility with high winds and blowing snow at Byrd, so there was no way a plane could land! We headed back into McMurdo and made it in time for dinner.

McMurdo is a small town and slightly more than 1,100 people are in there now, so all of our friends noticed that we were back. Everyone keeps asking when we are going to get to the field.  Well, we are going to try again today, December 7. We are scheduled for another flight with transport to the airport at 1645 this afternoon. Take off is scheduled for 7 PM and we’ll land at Byrd at around 10:30 PM if all goes well.

Actually, I think we were all secretly happy to have another Wednesday lunch in McMurdo because on Wednesdays we get cookies. We will all take a few extra cookies in our backpacks for a midnight snack at Byrd, if we make it tonight.

I am particularly anxious to get to Byrd soon because, this year, I will only be with the team until there. I will not be accompanying the team on the traverse. Once the rest of the team has left Byrd, I will head back to my office in NASA Goddard (Greenbelt, MD). My job this year is make sure the field methods, (drilling of the ice cores, taking the snow pit measurements and running the radars) are consistent with last year’s, and the team is trained and ready to go. Then I get to go home. I would love to stay with the team but I have an 18-month old son at home and last year I missed his first Holiday Season. This year, I want to be home. I am lucky to work with such a strong team so I do not have to be here for the entire time. Working in Antarctica is truly an amazing experience but with the austral summer being in December means that many polar scientists and workers spent their holidays away from family.

Keep your fingers crossed for good weather and hopefully the next post will be from Byrd!

SEAT: Satellite Era Accumulation Traverse: Chers lecteurs francophones

December 8th, 2011 by Maria-Jose Viñas

By Ludovic Brucker

Chers lecteurs francophones (que nous savons nombreux tels que familles, amis, et élèves de Goddard French Immersion Schéol), voici un petit récit résumant notre situation actuelle à Mc Murdo (77 o 51’ S, 16640’ E). Lors des prochains messages, nous essayerons d’avoir un court résumé du texte en français. N’hésitez pas à nous poser vos questions!

Tout d’abord, relatons l’objectif scientifique motivant cette campagne de terrain où nous ferons une traverse légère (déplacement en motoneiges et “nuitées” sous tentes) de 500 km durant le mois de décembre sur la partie ouest de la calotte Antarctique.

Nous cherchons à estimer l’accumulation de neige sur la calotte Antarctique, soit combien de centimètres de neige précipitent chaque année et s’accumulent avec le temps jusqu’à se métamorphoser en glace. L’Antarctique étant un immense continent d’une superficie d’environ 14 millions de km2 il est impossible d’obtenir cette information à partir de mesures locales obtenues depuis quelques stations. Par conséquent, notre objectif est d’utiliser des mesures satellites afin de retrouver cette information sur l’accumulation de neige à l’échelle continentale. Pour cela il nous faut tout d’abord obtenir des mesures in-situ pour développer des algorithmes servant à convertir la mesure satellite (celle d’un rayonnement électromagnétique, généralement dans le domaine des micro-ondes) en une grandeur physique (telle que accumulation de neige, température, densité, taille de grains de neige, ou encore présence d’eau liquide dans le manteau neigeux, etc.). Avec plus de 30 ans de mesures continuellement collectées par des radiomètres en orbite autour de la Terre, ces grandeurs servent au suivie climatique de la cryosphère en régions polaires.

Durant la traverse, cinq personnes seront présentes avec des rôles clés, définis:

- Michelle, au vue de son expérience lors de déploiements en régions polaires, est en charge du groupe. Après une prise en compte des idées/préoccupations de chacun, elle aura le dernier mot sur les choix stratégiques nous permettant d’évoluer en sécurité. Par exemple, il lui revient la décision de démonter le camp au petit matin afin de continuer la traverse, ou, au contraire, de rester une journée supplémentaire si le vent ou la visibilité ne permettent pas d’atteindre notre prochain point de ravitaillement en carburant (qui sera déposé dans quelques jours par avion). Michelle est également le contact radio avec le camp d’été à Byrd et la station McMurdo.

- Jessica et Randy s’occupent du forage de carottes de neige jusqu’à 15-20 mètres de profondeur, ainsi qu’aux premières analyses. Ils vont extraire des carottes d’environ 1 m de long et 5 cm de diamètre, puis les mesurer, peser et les mettre dans des tubes afin de les protéger. Ensuite, ces tubes seront transportés par avion jusqu’aux Etats-Unis.

- Clément travaille avec deux radars (bande C et Ku) que nous transportons sur un traineau spécial tracté par motoneige. Les jours de déplacement, Clément et Ludovic alterneront leur présence sur ce traineau et sur la motoneige. Comme vous vous en doutez, rester assis 8 à 10 heures à contrôler le bon enregistrement des mesures radars donne rapidement froid dans le dos ! Nous changerons donc de position très régulièrement. Durant les jours au camp, Clem passera l’essentiel de son temps aux révisions des instruments.

- Ludo, en plus de partager son temps avec Clem et les radars, réalisera des mesures des propriétés physiques de la neige dans des puits de 2 m de profondeur. En plus des mesures classiques de températures, densités, conductivité thermique, etc, nous prendrons également des photographies infrarouges permettant d’enregistrer  la stratigraphie du manteau neigeux, et d’estimer la variation verticale de la taille des grains de neige.

Notre équipe présente cette année en Antarctique est composée pour le moment de 6 personnes, les 5 déjà présentés plus Lora! Lora est une experte de la NASA dont la thématique principale est l’analyse de mesures par télédétection active et passive des manteaux neigeux en Antarctique et au Groenland. Elle a déjà réalisé 7 déploiements sur calottes polaires, dont 3 en Antarctique, elle a aussi passé 4 mois consécutifs à Summit durant un hivernage au Groenland. Sa maîtrise des préparations d’expédition est un atout incroyable tout comme sa connaissance de la station McMurdo. Lora va venir avec nous jusqu’à Byrd afin de s’assurer que tout soit parfaitement en place, puis elle rentrera dans le Maryland pour célébrer la Noel avec sa famille.

Les présentations étant maintenant faites, résumons les différentes étapes excitantes de ces derniers jours! Nous avons quitté les Etats-Unis le 17 novembre en direction de Christchurch (Nouvelle-Zélande) avec un passage par Los Angeles (Californie) puis Auckland (Nouvelle-Zélande). Après avoir perdu une journée en passant la longitude de changement de date, l’arrivée en Nouvelle-Zélande s’est très bien déroulée pour toute l’équipe.

Dimanche 20  a été consacré à récupérer nos habits polaires (voir les photos associées aux autres textes en anglais). Nous avons notamment reçu “Big Red”, cette fameuse parka rouge de la National Science Fondation (NSF) et du programme antarctique américain (USAP).

Lundi 21 fut le jour du départ pour l’Antarctique. Après un vol de 5h, le C-17 de l’US Air Force a atterri sur la glace de mer au large de la station McMurdo. Un moment magique!

Aéroport sur la glace de mer au large de McMurdo.

Nos premiers pas nous ont menés vers de particuliers engins, Delta et Terra bus, dédiés au transport en commun afin de relier la piste d’atterrissage à la Station de Mc Murdo.

Station McMurdo, vue du sommet de Observation Hill.

Les engins de transport à McMurdo sont soit équipés de chenilles, ou possèdent des roues d’une largeur exceptionnelle et d’une hauteur aussi grande que Clem!

Une illustration de la taille des roues des engins présents sur la base!

Mardi 22 et Mercredi 23, Jessica, Randy et Ludo ont suivi une formation de sécurité pour les déploiements en extérieur. Cette formation, bien mieux connue sous le nom de “Campeurs Joyeux!”, inclue une nuitée ensoleillée dehors, à proximité du Mont Erebus sur la plate-forme glaciaire de Ross. Pour varier les plaisirs, Jessica a passé la nuit dans une tente standard en forme de dôme, Randy dans une tente Scott en forme pyramidale afin de résister aux vents antarctiques. Sur recommandation de Clément, Ludo a quant à lui creusé une tranchée pour y passer une excellente nuit ensoleillée avec un panorama fantastique.

Le panorama depuis McMurdo est exceptionnel, nous profitons bien de la vue des montagnes car dans quelques jours nous seront dans une zone très plates...

Durant ce temps, l’autre partie du groupe a commencé la chasse aux caisses d’équipement envoyées depuis le Kansas en septembre dernier. Malheureusement, nos radars n’ont pas été trouvés… Apres quelques heures de recherches ils ont été localisés sur un bateau à Christchurch.

Durant la journée du Jeudi 24, nous avons tous apporté notre grain de sel aux préparations. Il s’agissait de préparer les caisses de nourriture pour les prochaines semaines, soit 350 kg d’aliments.

La dernière journée de cette première semaine était dédié à finir les préparations de toutes les caisses en partance pour Byrd. Malheureusement les radars n’étaient toujours pas arrivés à McMurdo due aux conditions météorologiques empêchant les C-17 de voler. Plus précisément, les avions auraient pu atterrirent sans difficultés mais durant la phase de descente ils avaient à traverser une couche humide qui auraient généré de la glace sur la carlingue de l’avion une fois posé. L’aileron de queue étant très haut sur ces avions et l’usage des produits dégivrant limité, aucun avion en provenance de Christchurch s’est posé depuis notre arrivé.

Dans l’espoir de recevoir très prochainement les radars, nous allons poursuivre notre découverte de Mc Murdo et de la base néo-zélandaise Scott durant le week-end de Thanksgiving.

McMurdo avec en arrière plan Mont Terror et Mont Erebus (de la droite vers la gauche).

 

SEAT: Satellite Era Accumulation Traverse: Waiting Again

December 8th, 2011 by Maria-Jose Viñas

By Lora Koenig

It’s Thursday, December 1, and I am, yet again, sitting in our office, waiting.  As the saying goes, “hurry up and wait”: This rings true in Antarctica. Last week, we were waiting for our radars to arrive on a plane from Christchurch. Usually there are about three flights a week from Christchurch to McMurdo, but an entire week of flights was canceled due to bad weather here. And finally, a plane arrived on Monday, November 28, bringing fresh fruit, new people and, most importantly, our radars.

Ludo and Clem quickly set up the two radars, ran a few tests to make sure they were working and repacked them for shipping to Byrd Camp. Normally we would take a few days to do this but, since we were delayed, we all worked hard and completed the tasks in a few hours. We repacked the equipment very carefully to prevent damage, and put it into the cargo system. (See Michelle’s blog post to learn more about the cargo system). Our intracontinential cargo needed to be in the system 48 hours in advance, and we were hoping to fly to Byrd on December 1 (that is, today).

Clem and Ludo testing the radars. The coil of wire, in the center of the picture, is a delay line that sends the radar signal through a wire that attenuates the wave. Delay lines are a good way to test the radar when the antennas are not yet hooked up.Clem and Ludo watching the radar echogram to make sure the radars were not damaged in shipping. Clem is holding a set of notes: We always have good documentation of our procedures to make sure we take consistent measurements. The notes also help us in case we forget anything.

Just as a reminder here is the location we are trying to get to.

So our estimated departure date has come and gone, and here we are still in McMurdo. This is not a big surprise; delays are common in such a harsh environment. We are now scheduled to go to Byrd on Monday December 5. All of our work in McMurdo is done, so we will use the delay to rest a bit before the hard work of the traverse begins.

Michelle and I took advantage of the nice weather to go skiing on the McMurdo Ice Shelf, which is connected to sea ice. In a few weeks, people will not be able to ski here anymore because the warm summer temperatures from both the air above and the water underneath the shelf will thin the ice.

Why are we delayed? First, as I mentioned, McMurdo had a week of bad weather and no planes could land or take off.  And once the weather in McMurdo cleared, it was Byrd’s turn to have bad weather, so planes could not land there. On top of that, there is a lot of science going on at Byrd this season, including another traverse lead by a NASA colleague, Bob Bindschadler, headed to Pine Island Glacier. (Check out this video on the Pine Island project, or visit their website.) Because there are so many teams flying to Byrd, we have to wait for five flights to get in before we are assigned a plane load for our science gear, fuel, snowmobiles and ice core boxes. Our team has a full LC-130 plane load of gear that needs to make it to Byrd.

Yesterday, they were finally able to get some flights into Byrd. Our flight number is T012; flight T010 will take off for Byrd this evening, then T011 has to fly and then it’s us. We are watching the monitors in McMurdo that show the flight status, just like at the airports, hoping that flights get in. We cheer when a flight returns and groan when a flight is canceled due to weather.

There is one more issue that is causing delays.  This week they are moving the runways at McMurdo. In the early season, when it is still cold, the planes land very close to McMurdo on the sea ice at a place called Icey Runway. As temperatures warm, sea ice thins and the runway is moved farther inland to Williams Field, where the ice is thicker. This weekend is when they move airports, so there are no flights scheduled for Friday or Saturday (normally, there would be flights Monday through Saturday). So we will have another weekend in McMurdo, and when it’s time to fly to Byrd we’ll do it from William’s Field, about a 45-minute drive from McMurdo.

While we were waiting, I finally took some pictures of Percy the Penguin. Percy was given to me by a friend; it came from a geocache site in Seattle, WA and has now made it to Antarctica. Percy is actually the only penguin we have seen here. So far, the only wildlife we have encountered are skuas, large seagull-like birds, and Weddell seals that lounge on the sea ice just outside of McMurdo and Scott base.  Through there are no seals in the picture of Michelle skiing, she is on an ice shelf below which the seals could be swimming. When the seals find a hole in the ice they come up onto the sea ice or ice shelf and lounge in the sun.

Percy the penguin overlooking McMurdo Station.

SEAT: Satellite Era Accumulation Traverse: Happy Camper School

December 2nd, 2011 by Maria-Jose Viñas

By Ludovic Brucker

Jessica, Randy, and I were scheduled to attend a 2-day Field Safety Training Program (a.k.a. Happy Camper survival school the nickname makes it sound much more fun than its official title!) on Tuesday and Wednesday, 23-24 November. The training includes spending a night outdoors. I heard about the program months ago and I was definitively looking forward to this enjoyable and educational experience. The invitation read: “Be sure to show up the morning of your course dressed for the field in your Extreme Cold Weather (ECW) clothing.  […] Trust us!  We want you to be comfortable and safe for the Antarctic environment.” Sweet!

Our group on our way to the Happy Camper site, near Mt Erebus (on the left, 3794 m, or 12,448 ft, high).

On Monday evening (Nov. 22), I had carefully prepared my ECW++ pack (the ++ stands for water and food). My ECW gear consisted of: socks, bottom and top thermal base- and mid-layers, a fleece jacket, a thick bib, Big Red, boots, and all the basics (such as hat, gloves and glove liners, mittens, face protection, etc). Additionally, we took the sleep kits and tents that we will be using during our traverse. These last two are very similar to the ones you most probably use when camping, but the sleeping bag is much thicker and we also use pads, a fleece liner, warm fleece pants, and a pee-bottle. Our bag also contained other basic and mandatory items, such as sunglasses, goggles, sunscreen, lipstick, and water bottles, among other things.

The first morning of the training was dedicated to listening to lectures about the harsh Antarctic environment and its rapidly changing weather conditions, with focused courses on topics such as how to deal with hypothermia, etc. We then headed out to the field a few miles away from McMurdo station, in the vicinity of Mt. Erebus. It was gorgeous! We were a total of 20 people, all freshly arrived from New Zealand the day before.

Jessica in her ECW gear.

The outdoor session was much cooler (pardon the easy pun) than the lectures and it provided us with information on setting up camps, such as mounting a mountain tent and a Scott pyramid tent. The latter is particularly well suited to Antarctic conditions and it’s inspired in the tent Robert Scott designed for his 1910-13 South Pole expedition. It resists high wind speeds very well; we will have one in our traverse. Obviously, the tent resistance to wind is all about the quality of its snow anchors.

Folks setting up Scott tents.

Our BYU team members (Jessica and Randy) installing anchors in the snow to strongly fix the Scott tent structure.

Instead of spending the night in a tent, I opted for the alternative, which was digging up a trench and sleeping in it. “Why not,” I thought. “I’d rather experience my first night in an Antarctic trench when the weather is pleasant and I have resources close by than when I have no alternative to using a trench.”

A general view of our Happy Camper site with yellow Scott tents (right), classic mountaineering tents behind a wall made of snow bricks that protects the tents from the wind, and trenches (front).

Our dining area, with boiling water for tea and dehydrated meals.

My trench had a narrow opening and got wider a few feet deeper. The ceiling was made of snow bricks covered by lighter snow to close joints and holes. I used my bag as an horizontal ceiling door, right above my head. An easier option would have been using a sled for the ceiling, as others did.

A view of my trench. It is narrow at the top and wider at the bottom. Being 6 feet 3 inches tall meant I had to dig a long trench.

Me finishing up a few details to ensure an enjoyable stay in my trench.

The interior of my trench.

My night was perfect: cozy and unbelievably quiet! I didn’t even notice that the wind had started to blow strongly during the night. I woke up around 4 AM feeling a bit chilly; I ate a chocolate bar, drank some water, and went back to sleep. It was interesting to wake up in the middle of the night and be able to see like if it was day time. At this time of the year in Antarctica, all nights are bright, with only one star in the sky. It felt weird to be sleeping in a snow trench only three weeks after having slept in a hammock hung between palm trees in Big Island, Hawaii. Thanks Lora and Thorsten for these two experiences!

Happy Camper also taught us how to use a High Frequency radio. It is significantly different to use from the common very high frequency radio. After deploying the two 10-meter antennas, we made calls to South Pole station (1360 km, or 850 miles, south of us.)

In summary, these first two days outdoors were successful. However, we expect tougher conditions once we’re out in the field, in the West Antarctic Ice Sheet.

SEAT: Satellite Era Accumulation Traverse: We are in Antarctica!

December 1st, 2011 by Maria-Jose Viñas

By Ludovic Brucker

Our military C-17 flight landed on 2.3-meter thick sea ice in McMurdo Sound. McMurdo has three airfields that are used at different times during the austral summer. The sea-ice runway is located a few miles from McMurdo, and it usually operates from October to December, until the sea ice begins to break.

For a large number of us, this is our first time on the southernmost continent on Earth and, as you can imagine, landing on McMurdo Sound’s sea ice felt very special. The first minutes off the plane everyone was looking around and smiling a lot.

Michelle and Clement posing in front of the C-17 landed on sea ice. They are extremely glad to be again in Antarctica, for their third and second deployment, respectively.

Weather conditions on landing were nice, despite a low cloud that turned everything extremely bright and made it difficult to tell the sky from the snow-covered ice.

Shortly after stepping into the snow, we had to jump into one of the two charismatic vehicles that were ready to transport us to McMurdo Station. We could choose between the famous Ivan the Terra Bus (red as our parka, a.k.a. the Big Red) or an orange delta truck from the early 80s (that vehicle was already carrying people from the runway to McMurdo station before I was born!). Both vehicles have incredibly big tires.

Ivan the Terra Bus. Check out its tires!

A delta truck from the 80s that can carry about 20 people.

The ride to the station normally takes 15 minutes, but it can be four times longer when sea ice conditions aren’t safe anymore and the runway is then re-located on the ice sheet farther from the station.

After a warm welcome and a short briefing at McMurdo, we got our room keys and headed toward the dormitories. That gave us the first opportunity to walk a bit through the station. McMurdo Station (located 77° 51′ S  166° 40′ E) sits on bare volcanic rock on the coast of Hut Point Peninsula, Ross Island. The station was built in 1955; its 85 or so buildings range in size from a small radio shack to large three-story structures. It is the largest Antarctic station and the logistics center for the U.S. Antarctic Program. There are repair facilities, dormitories (for a maximum of 1200+ people), administrative buildings, a firehouse, a power plant, a water distillation plant, a wharf, stores, clubs, warehouses, and a science and engineering center (where we will spend some time before heading to Byrd, hopefully next week). All the structures are linked by above-ground water, sewer, telephone, and power lines.

Some McMurdo buildings, with Observation Hill in the background (750ft, or 230m, high).

An example of above-ground water and power lines.

View of the sea-ice runway from McMurdo station.

By the time I checked into my room and picked up my bag, a cold, light snow had started to fall. How nice! In the next days, we are going to go through several training sessions, make sure that our scientific equipment made it here undamaged, and prepare our shipment to Byrd station.