Project S.C.I.N.I.: December 2007

Tuesday, December 11, 2007: Farewell!

Last Sunday we said our farewell and thank you to the community. Many people have volunteered to help us, taking time off work to come drill holes and haul heavy gear around. Even more have helped us as part of their jobs, but have done much more than that, making themselves available after hours and for inconvenient requests. We very much appreciate all that everyone has done to make things go well. So on Sunday, we set up both ROVs and invited our friends to come out and see underwater Antarctica for themselves.

Underwater life in Antarctica.

(continued...)

Now that we have finished our field work for the season, we are returning all the borrowed gear, equipment, vehicles, etc. Whatever we don’t return, we have to account for! So far, we are only missing two ice screws, which is pretty good, considering that the list of borrowed items ran to 14 pages long.

I have a theory that ice actually eats ice screws. Look at those teeth!

All the stuff that we need to bring back to with us, we have to pack up for shipping home. There are a multitude of options in terms of speed, temperature control, and expense, but all have a lot of paperwork associated with them, which has never been my strong point. We have 19 crates and boxes, before we even get to our personal gear.

Crates 1 and 2 out of 19...

And to make it all the more challenging, the weather has finally gotten nice. Clear blue sky all day makes the mountains seem so close. The sun is warm though in the shadows or a breeze it is still very cold. Nighttime walks are a wonderful way to wind down for sleep.

On a bedtime hike, Bob holds communications for the kiwi station on his fingertips.

Thanks to you too for your interest in our work and for all your comments and questions. Remember, this is only the first season of a three year project! We will update periodically until we deploy to Antarctica again in October 2008. Please come visit us again!

I'll leave you with some of my favorite images from this season -

Full Post (posted by stacy @ 18:30) 0 Comments

Monday, December 10, 2007: Ridges, Open House

Last friday I got to tour the pressure ridges near Scott Base with a small group. Our leader was Ann Bancroft, a member of the American Women's Antarctic Expedition to the south pole back in 1992, who now works as the site manager for the long duration balloon project.

Also, yesturday was the last time SCINI went in the water this season, we hosted an open house for the McMurdo community down at the jetty with both SCINI and VideoRay in the water...

(continued...)

The pressure ridges were a special treat as us Americans are usually prohibited from this more dangerous, constantly changing area. The pressure of the thick Ross Ice shelf (out of sight from the shore) pushes this thinner sea ice up against the rocky base of Observation Hill in front of Scott Base; the crevases and peaks sometimes rise so fast you can see the landscape moving from the New Zealander's base.

Here are some final clips of SCINI and video ray driving together, which gives a much better idea of how the two vehicles interact and their scale compared to the objects they investigate.

Here are 2 clips of VideoRay from SCINI's perspective, first with scaling lasers powered up (you can see the algea bloom is getting thicker this time of season as the laser's path lights up particles) and later lighting up a rock scene with nice warm bright external lights. You can really see the difference in video quality, though of course the VideoRay's more polished lighting and dome close the gap a lot:

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VideoRay Lasers(download, smaller).

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VideoRay Bright(download, smaller).

And here's SCINI manuevering around some benthic life, then shooting off into the unknown, never to be seen again...

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SCINI investigating (download).

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And away! (download).

Full Post (posted by bnewbold @ 13:08) 0 Comments

Sunday, December 9, 2007: Tales for the Spicy Penguin

Penguino, Penguino,

He's Nice-O!, Not Mean-O!,

Penguino!

(continued...)

Shortly before my son Jack was born my wife and I watched March of the Penguins and something from it stuck in our subconcious... Not long after he entered the world he became El Penguino.

When he was just a few days old and I was doing the midnight feedings I would sing the above rhyme to him. Over the last 2 years he has collected a few more nicknames, The Small Man and Mr Helpful being the most prominent, but he is still El Piquante Penguino de Quispamsis.

The Small Man doing what he does best. And ceaselessly.

Drumming...

and robbing passers-by.

So it was clear when the chance to visit Antarctica prsented itself I had to come back with penguin pictures, movies, trivia, tales, and even a hitchhiker if I could manage it. All but the hitchhiker turned out to be possible. Luckily I was able to use the SCINI project to lure Peque, the World's Most Technically Astute Penguin, into travelling with me. He has really enjoyed himself, and at cape royds he made friends with a seal who was interested in using our dive hole.

As luck would have it a dive trip to Cape Royds came up and with only a little abject pleading I was able to convince Stacy to take me along. When we got there I was amazed to see that the dive was going to be done through a hole melted in a crack in the ice. We had to break up the ice that had formed over the surface of the hole and dip it out with a bucket.

After the dive we went over to the penguin rookery and Shackleton's Hut. The Hut was impressive. The wind was really biting and the snow was blowing and it was overcast. The men that wintered in that hut had weeks at a time where the bad weather we were experiencing would have been a welcome respite from the continuous storm they sheltered from in that little wooden hut.

The most important feature was a great old stove. I want a beautiful stove just like that to put in my house. It must have been a fight to see who got the bunk closest to the stove.

The warmest thing in their world

Just outside the hut was the penguin rookery. I sang them the Penguino rhyme, but the wind must have blown the words away because they did not respond. There were about 4,000 breeding pairs of penguins living in the area.

Lots of Birds...

We were at the end of the world. The sea ice ended and we could see the open water of the Ross Sea. And the penguins trekking over the ice for about a mile to jump in and fish.

We had a tour guide in the person of Dr David Ainley. He lives at Cape Royds and studies the birds. He turned me on to the excellent Penguin Science website: http://penguinscience.com/ He knows what there is to know about the birds, and is of the opinion that Happy Feet was a movie full of truth and good messages. I asked him about the singing and dancing and he allowed he had seen no dancing (yet) but that penguins do recognize each other by their distinctive individual voices, so that singing part of the movie was not so far fetched. Looks like Jack gets a dvd for Yule.

One of the great things at Cape Royds is Penguincam! If you look at the "hut pic" for 6 Dec 2007 you can see a couple people in red jackets who Rusty and I have decided must be us (they don't get a lot of visitors).

The aliens have landed

The website has tons of pictures of penguins being at home and you can see what the weather is doing at any time. I took the following movie standing just in front of the Penguincam. Check out the flag beating itself ragged in the stiff wind.

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PENGUIN FLAG! (download).

So there you have it. I came with a clear mandate to collect penguin experiences and I can return to El Piquante Pinguino de Quispamsis with stories, pictures, and a feathery little friend suitable for cuddling and assisting on whatever engineering projects The Small Man comes up with in the next few years.

It turns out that while I have been down here winter has arrived back in New Brunswick and El Penguino has started training for his own Antarctic expedition.

Full Post (posted by BLee Williams @ 20:09) 1 Comments

Saturday, December 8, 2007: Art at McMurdo

Even in the land of ice and snow, human natures primordial need for self expression burns hot. Long winters and brief interludes from work allow time for minds to wander and creativity to flow. Below are examples of the art forms that one finds when in and around town. Take a self guided stroll through the interesting and sometimes weird art of McMurdo Station.

(Continued)

In the stairwell to the Crary Library

Wall in the Science Cargo Building

Boiler in the Science Cargo Building

What's under the walking Bridge?

The bridge troll of course

Crary Lab Hall

Near the Fuel Tanks

On Hut Point- Lovingly called "Roll Cage Mary"

Another Bridge Troll

At the galley entrance

In an out of the way hall is this piece with the heart and souls of McMurdoites when asked the question of "Why did you come to Antarctica?" Zoom in and read why some came.

Full Post (posted by Rusty @ 20:34) 0 Comments

Friday, December 7, 2007: No Words, Only Pictures

(continued...)

Full Post (posted by Nicholas @ 23:55) 0 Comments

Thursday, December 6, 2007: Antarctic Hitchikers

Today we made the long trip out to Cape Royds one more time, to take advantage of a hole that David Ainley, Adelie penguin researcher extraordinaire, had for a current meter. My interest in sampling in this location is based on the penguins, but not just because they are oh-so-cute…

An Adelie penguin, Pygoscelis adeliae, poses for the camera.

(continued...)

But because there are lots of them, and they poop. The colony has about 2000 breeding pairs, who at this point are incubating eggs. As it was a mildly blustery day, the penguins were all head on into the wind, with the precious eggs tucked well out of sight. The buildup of guano from these birds is impressive, though perhaps not as stinky as guano piles in more temperate climates. During the warmest months, snow from the heights melts, runs into Pony Lake, and eventually through Pony Stream into the ocean.

A guano deposit from years of penguin occupation at the colony at Cape Royds.

Are you seeing why I find this interesting? The penguin poo is a source of organic or food material in a food-poor environment. Many benthic animals in the Antarctic respond rapidly and strongly to food input; some, such as seastars, are mobile and move in quickly to feed, others, such as worms, settle from the plankton and grow and reproduce rapidly. These opportunists change the community structure. I’d like to determine if there is a different ecology adjacent to food sources like penguin and seal colonies.

The seastars Odontaster validus have a “dine and dash” strategy.

When I returned from my dive I was surprised that the number of tenders had doubled from 2 to 4. As we were kind of out in the middle of the seaice, I wondered where they had come from. When I got enough gear off and my lips warmed up enough to form a coherent sentence, I learned that Hugh and Chris were with PolarDiscovery, and as the wind was blowing, their helicopter ride back to McMurdo had not shown up for the second day. They wanted to know if they could hitch a ride back to town with us. They gave us chocolate, so we were happy to accommodate ☺. You can see more of their adventures at http://www.polardiscovery.whoi.edu/expedition3/journal.html

Our long day was rewarded with this beautiful view of the Barne Glacier in front of Mt. Erebus. A good end to a day that started with Nick singing "Rudolph the Red Nosed Reindeer" to me on the comms box.

Full Post (posted by stacy @ 02:30) 0 Comments

BLee just put up an old post that won't show up on this front page, check it out here!

Full Post (posted by bnewbold @ 23:58) 0 Comments

Pretty Pictures

Bob and I spent the last couple days down at the jetty doing some lighting and v
ehicle dynamics testing and we've got hours of video to pick through as an indir
ect result. Here are a few choice frames to peruse, plus a couple LIVE ACTION
video clips at the end.

(continued...)

Some of these are reasonably high resolution and you can make out more details if you click on them for the original file.

Le Video

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A bivalve claming up (download, smaller).

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An underice Antarctic dustwand RETREATING from our sun-like beam (download, smaller).

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Another example of benthic life fleeing from SCINI. This was by far the most agressive driving maneuver we tried, I think it's interesting how only part of the anenome responds. (download, smaller).

Thanks for playing...

Full Post (posted by bnewbold @ 12:23) 2 Comments

Tuesday, December 4, 2007: Bring a Hankie

I'm sure everyone is going to post about the Grand Day Out to Cape Evans. So I'll just cut to the heart of the matter.

(continued...)

I'm sure everyone is going to post about the Grand Day Out to Cape Evans. So I'll just cut to the heart of the matter and sum up why you should turn off your computer, get up off the couch and do whatever it takes to get out in the world right up past your ears. And bring a handkerchief...

Blee compares nostril size with his new friend Lester

We were at a dive hut part of the day at Cape Evans and a great fat Weddel Seal was using the dive hole thru the ice as his house. The seal (Nick appeared to know him and claimed his name was Lester) breathed so powerfully his exhalation was moving my hair 8 feet above him. He blew snot on me; I chose to believe in welcome. Thats the really cool part of these jobs: the snot. You can't get that from TV or a movie.

You know you are really there when you feel the snot.

Full Post (posted by BLee Williams @ 02:18) 1 Comments

Monday, December 3, 2007: Details of an Ice Dive

We have given several glimpses into diving beneath the ice but looking back through the earlier posts I see we haven’t given a good description of all the effort it takes to actually do a dive here. We have been doing sampling dives about every other day so I’d like to give a start to finish description of the effort involved with making those dives.

(continued)

Yesterday’s dive at Cape Armitage started off snowy with limited visibility so even a short mile from McMurdo we couldn’t see the location where we were supposed to set up the new dive site. Skeptical, I loaded the Tucker with a shovel and a large dip net and headed to meet Tom and his drill rig. The rig is a tracked Caterpillar bulldozer, called a Challenger, pulling a tracked drilling rig and followed by a tracked trailer with drill bits. I followed Tom out of town because I figured even with my inexperience, I could follow a big yellow bulldozer in falling snow without getting too lost.

The visibility gradually improved so we were able to GPS and flag the location of the dive holes we needed to drill. After mounting the 4’ diameter drill bit on the drive shaft we started to drill but soon realized the snow was about four feet deep on top of the ice. That’s a problem because it leaves the water level too far down in the hole for divers to climb out of the hole. We stopped drilling, unhooked the drill rig from the Cat and Tom started removing the snow down to the ice surface. I was surprised how hard and compact the snow was here and how much effort it takes for a big bulldozer to cut through the snow. It is not soft and fluffy like one would think and took close to an hour to remove. With the snow cleaned from the surface of the ice we were able to again position the drill bit in the hole and continuing drilling through the ice.

As the drill bit cuts, the snow and ice chips pile up in a cone around the hole. Fast shovel work is required to keep up with the drill with the main goal to keep a path in the cone clear for water to flow out when the bit breaks through the ice. Well the bit broke through the ice OK and the water flowed, but then it kept flowing and flowing, starting a lake.

Realizing that the ice must have been pressed down slightly below sea level by the weight of all the snow, we quickly built a snow dam in the cone to stop the flow. Tom then had to move a foot of snow back in around our hole just so the dive hut wouldn’t be sitting in a lake of freezing water. Freezing your dive hut into the ice is not a good idea. Once the hole was finished and the snow was smoothed for moving in the dive hut, the dip net became the weapon of choice. There are a lot of ice chunks and slush that must be dipped out, one net at a time until the surface is ice free. Each full net is heavy so it’s a workout to clear the hole.

When we finished clearing the hole, we towed the dive hut and positioned it over the hole in the ice. With careful aiming we got it right the first time.

We then drilled a second hole a few hundred yards away going through the entire process all over again. It took half a day but that's what it takes to get the dive holes ready for divers.

Next step is readying dive gear in the dive locker and partially suiting up. The base layers that keep you warm under the actual dry suit are a layer of thermal polypro underwear and then a thick fluffy insulated jumpsuit. On each foot I wear a liner sock, a neoprene sock, a wool sock and an insulated bootie that goes over the top of the other three. Getting into the dry suit wearing all that insulation should constitute a Yoga routine. Hands are then wiggled through the wrist seals while making sure that the small plastic tubes called “tubies” lie properly on your wrist and protrude through the wrist seals. These little tubes are critical because they allow air to move into your glove, keeping your hand from getting tightly squeezed during descent. They also allow you to move warmer air from around your body into your gloves by shaking your hands vigorously above your head when your hands get cold. Next is getting your head through the neck seal, particularly difficult for divers like Nick with little necks and big heads. There are two main zippers on the suit that seal you in for what you hope is a dry dive.

Our other dive gear consists of the air tank with two tank valves, each with its own separate regulator. This redundancy is a safety measure in case your primary regulator freezes and free flows air while you are doing your dive. The second regulator is on your chest within easy reach so you can switch regulators when needed. Switching regulators is a skill you must demonstrate on your check out dive here before you are allowed to continue diving in Antarctica. It sounds like a simple feat but the restricting tightness of the hoods and frozen lips makes it difficult to get a regulator in or out of your mouth. The dive guru here, Rob Robbins, demands that skill even though he says that the regulator freeze ups happen on less than 1% of the dives. I’m really glad however he made us practice that skill because I have had two free flows out of ten dives. I guess I'm really messing up his low freeze up percentages. The risk of freeze ups mandates diving with a buddy essential because the bulky insulation and dry suit make it extremely difficult to reach around and turn off your own valve to the free flowing regulator. On your own you have to quickly take your tank off to reach the valve so having your dive buddy there to turn off the valve to the free flowing regulator keeps the air in your tank and your stress level down- Thanks Stacy! Twice!

All this dive gear and the sampling gear are loaded into the Tucker and for the drive to the dive site. Once at the dive hut everything is unloaded from the Tucker into the dive hut. Preparation for the dive begins with again clearing the ice from the dive hole and then setting up our safety line. This weighted line drops through the ice hole and extends to the bottom. Spaced along the line are flags and three flashing strobes and a small emergency air tank with a regulator. The flags and strobes help us keep track of the dive hole in the twilight to dark conditions under the ice. Also attached to the bottom of the line is our box of sampling cores, an underwater digital camera and an underwater video camera.

Final dive preparation begins sitting on the edge of the hole and wiggling in to a shoulder harness weight belt weighing forty pounds. Two pound weights are then strapped on each ankle and fins are strapped on. All important dive computers are fitted to wrists or hoses and the air tank backpack is loaded on and air is turned on to both tank valves. Note that in under ice conditions, no buoyancy compensators (BC) are used because rapid assents to the surface are a bad idea, creating more danger than safety. Slushy frazil ice under the sea ice can obscure a diver pressed up against the ice, plus it's very difficult to see your dive hole when at the bottom of the ice. Proper boyancy is therefore acheived by adding or releasing air directly from the dry suit. It takes some practice but good control of your boyancy using the dry suit becomes second nature. On the head go a neoprene "gorilla mask", a thick neoprene hood and finally a latex hood. These three hoods keep my head surprisingly warm and dry but at the price of being a bit constricting and claustrophobic. It’s sure better than a wet head, but I prefer to put these on at the last minute possible before the dive.

The face mask gets its requisite spit and is filled with icy seawater so it won’t fog up. By this time I am usually getting overheated and sweating inside my suit and anxiously looking forward to getting in to the cold water. Each hand gets a wool glove and then the dry glove is stretched over a sealing ring in the dry suit for what you hope are dry hands (sometimes these leak- ask Nick!). Putting on dry gloves requires help from another person so we always have at least one dive tender assisting divers throughout the preparations. My mask goes on last and the dive tender works the mask seals under all the hoods so the mask will seal against your skin. A final check of the gear, grab a dive light and then you are ready to drop in the hole ....

...unless the hole is plugged by a thousand pound seal breathing in your hole. In that case you just wait until the seal is willing to let you use his breathing hole. Breathing holes are critical real estate here and the Weddel seals aggressively defend their breathing holes against other seals. Fortunately they seem very unconcerned about us divers using "their" holes.

Dives typically take around thirty to forty minutes to complete the sampling, explore the area and safely ascend back to the surface in the dive hole. Each diver has to ascend through the ice hole singly while the others wait just below the ice. Occassionally we even have to wait for a seal to vacate the hole before we can make our final ascent to the surface.

Tanks and weights are removed and lifted off the diver and fins removed so that the diver can climb a metal ladder that was lowered in the hole during their absence. Once out of the water, mask and gloves come back off and you stand next to the hut’s heater trying to get your lips, fingers and toes functional again. For me it’s only these extremities that get cold and the longer the dive the colder they get. It’s manageable though and each dive the cold seems less of an obstacle.

The conclusion of the dive means bringing up the down line loaded with samples and cameras, reloading the Tucker, driving back to the dive locker and spending an hour cleaning and prepping gear for the next dive. Samples are processed, cameras are downloaded and cleaned and finally much food is eaten to replace all the calories burned during the day.

Subsequent review of the digital images or video sometimes leads to the dissappoinment of finding the data unuseable for one reason or another. That forces a return to the site to repeat the sampling. Unfortunately the hut has often already been moved so the the dive is repeated without a warm hut. It's good incentive to get it right the first time.

Yesterday’s dive at Cape Armitage took us a total of about 9 hours to complete. It's a lot of work to do a dive in Antarctica but just seeing these unique and beautiful under ice communities is reward enough.

Full Post (posted by Rusty @ 01:46) 2 Comments

Sunday, December 2, 2007: Weeks of testing finally pay off

Today was one of the most eventful SCINI days we have had in a long time. BLee, Bryan, Bob and myself planned on launching SCINI so that we could evaluate her performance over several engineering test that BLee had established. These tests were going to help determine if SCINI was ready to take on science missions. In the past I felt we have really rushed into getting SCINI in the water for science missions without having strict test to judge her performance. But today’s test was solely focused on maneuvering and reliability. The past two weeks have focused on making the robot reliable and has helped to build our confidence. Now after weeks of testing SCINI was ready to get wet once again.

(continued...)

The weather today started off with blue skies and lots of sun. It was as if Antarctica granted SCINI approval to dive beneath the ice shelf. In the lab Bob did a dry run of setting up the whole computer system with some help from Bryan. Bob is the cohesion in this project and he will be the one to carry on the lessons from this season to the next two years. During this dry run BLee and Rusty prepared our navigation holes while I worked the GPS system. These simply tasks sound quick and easy but let’s not forget we are in Antarctica. By the time everyone was on the same page, task wise, and it was time for lunch.

After a fabulous Sunday brunch we were packed, loaded and ready for our test. At the dive site we unloaded everything and once again allowed Bob to set up the operation but this time without the help of Bryan. This was Bob’s true test and he passed it with only asking one question. Before SCINI is dropped in the water we have established a pre-deployment checklist to ensure that all of the motors spin and in the correct direction, the lights turn on and off and that we are able to capture video. Thanks to previous weeks of testing SCINI passed the test without any problems and was ready to get wet. BLee took over the piloting position while Bob deployed the robot.

Once in the water the first test we conducted was a maneuverability test. One example of this test was to drive the robot laterally so that the vehicle would move sideway without changing its direction. SCINI passed all six maneuverability test and we moved onto the depth test. We have two sensors that measure vehicle depth. One sensor is located on SCINI and the other sensor is located on the transponder of the navigation system. The navigation system has a default depth sensor that we wanted to verify with an external sensor. To check the depth of both of the sensors we can place a tape measure down the dive hole and compare the readings of the senor to the tape. Both of the depth sensors checked out within a meter of each other and this was acceptable. Next we moved onto the navigation test. First we tested the noise levels of all three transducers while the robot was at a standstill. If there is too much noise our navigation system won’t work and we will have sporadic navigation that will be unusable. Our navigation noise levels checked out just fine and we moved onto navigation tracking while moving. There was some difficulty driving the vehicle at this point and it could have been a result of several things. For whatever the reason we were unable to complete our maneuverability navigation test so we moved onto driving test. These tests were similar to the previous ones but required us to pick an object at some distance away and follow it straight ahead and another object vertically in the water column. The two other tests required SCINI to hold a position in the water column while looking at an object and was followed by a test that point the camera bottle at the bottom of the ice. These tests were designed to judge if SCINI is capable of mapping physical features along the ocean bottom. Again due to driving difficulties we were unable to complete the entire driving test.

We were unable to complete many of our designed tests but left the dive site with a huge accomplishment. The total time of our test ran nearly five hours and this was the longest duration we had ever run SCINI without turning her off. Not only does this prove the reliability in a single dive but five hours is much longer than any science dive will ever require. So in the end we had some victories and we will head back to the lab to plan out where SCINI should go from here.

Full Post (posted by Nicholas @ 21:13) 0 Comments

Saturday, December 1, 2007: A shorter list

With SCINI almost completely rebuilt and tested, and only 2 weeks left, it’s time to reevaluate what we can achieve in the remaining time, without making ourselves too crazy. We have been remarkably successful so far, and we’d like to keep that high note.

SCINI beginning underwater explorations, with the hole in the ice visible in the background.

(continued...)

Our engineering goal for the season was to fine tune the navigation system. We were concerned before we arrived that echoes between the underice surface and the seafloor would confuse the positioning system. The software settings gave an option that helped us minimize the underwater noise, giving us positioning accuracy down to 10 cm. However, we learned that topside noise is a problem. The generator needs to be grounded, even if it has a noise filter. This has led us to consider solar power rather than petroleum-based engine power. More difficult to deal with is noise from undefined radio frequency sources, which is intense and sporadic around McMurdo. Unshielded cables function as giant antennas, picking up the noise and relaying it into the navigation system as error. Thus, shielded cables must be run across the ice. We also learned that it is easy to get transducer cables stuck in the ice, because they are running through small holes that refreeze quickly. Our solution has been to start with larger holes, place insulative plugs in them, and rigorously maintain them every half hour by dipping out the forming ice with a soup ladle. Next year, our approach will include placing small heating coils in the holes (like aquarium heaters) that can also be run off the generator or solar. This should keep us from having to run any more ‘ducer rescue missions! So we have two things we can improve for next season (longer shielded cagles, and heaters) but we are overall pleased with the performance of the navigation system. We have demonstrated consistent, accurate underwater navigation, a success!

One of the three transducers that make up our navigational net hanging beneath the ice.

Our science goal for 2007 was to find “the Lost Experiments”, and map and survey them. Up to 40 years old, these structures include experiments on predation, succession, larval dispersal, and substrate selection. Initially set up by Dr. Paul Dayton, their locations were based on visual lineups, and their depths sometimes exceed current safe diving limits. The ROV allowed us to overcome both of these issues, by letting us search safely at depth for hours, and by tying the underwater navigation net into GPS to get positions we can easily return to. We are enormously pleased that we found all of the sites, and one of our goals for the remaining time here is to complete the mapping on two of them.

One of the many experimental structures showing remarkable colonization and growth.

Other progress that we have made is harder to quantify - or at least, harder to define as completed. In our work at New Harbor, we proved that we can deploy SCINI in remote areas with limited support…but can we get even more remote, and with less support? The operational limits for successful missions have not yet been set, or even pushed. We have shown that we can overlay data collected under different navigation nets, but can we overlay data collected from different dive holes, expanding the area of seafloor that is known? We can exceed diving depth limits – but how far can we go? Different modeling calculations for pressure vessels give us different results, and tether constraints on mobility are as yet unknown, so the only true test will be a real world one. We can use sonar to map hard manmade structures; can we also identify biological targets such as giant sponges?

A sponge, such as the Calyx arcuarius shown here, is soft bodied, but has silica spicules and a different density that seawater. We won't know until we try how "visible" sponges are to sonar.

But that is getting past what we plan to accomplish in our remaining time this season. We have seven small goals left, and 7 days to complete them before we must begin packing up. How far do you think we’ll get?

SCINI illuminating the Antarctic seafloor communities.

Full Post (posted by stacy @ 18:35) 1 Comments

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