January 8, 2011
Mission Blue: Waiting On Weather
By EDIE WIDDER
We've been WOW: Waiting On Weather. So much of what we do at sea is dependent on the weather, or more specifically the sea state. We have three- to four-foot seas at the moment, which is smooth sailing by some standards, but too bumpy for submersible operations.
A submersible is fine strapped to the deck or tooling around beneath the waves. It's just that transition through the air-water interface that's the problem. That's when things get dicey. A 6,000-pound sub dangling on the end of a cable on a rolling ship makes for a heck of a pendulum.
The same goes for big nets or Remotely-Operated Vehicles (ROVs), which together with subs are the primary tools available for studying life in the deep ocean.
I have often dreamed of a deep sea lab like the one in the movie The Abyss, where you can enter and exit through pressurized hatches the way they do in space. But in space, the pressure difference is only one atmosphere, about 44 pounds per square inch. That's the weight of a five-gallon bucket filled with water. Imagine holding that on top of your head--not comfortable, but you could do it. The hatch on a spaceship must be able to withstand that force from the pressurized interior pressing outward toward space.
But now imagine you're down in the ocean at 5,000 feet, the approximate depth of the Gulf oil spill. At that depth, we're talking about the weight of more than 50 buckets of water--more than 2,200 pounds--per square inch pressing inward. That hatch would have to be a pretty amazing piece of engineering. The submersibles and ROVs we send to that depth must be carefully designed to withstand such enormous pressures without imploding.
The deep sea's inaccessibility and its inhospitableness to humans aren't the only challenges faced by those trying to study life there. There's also the puzzle of how to study that life without disturbing it, or worse, scaring it away.
Submersibles and ROVs have noisy thrusters and bright lights that can be highly disruptive. Camera systems left on the bottom are much quieter, but most still use bright lights that can literally blind deep sea dwellers that have sensitive eyes adapted for seeing the very dimmest of downwelling light or bioluminescence. These are the challenges that ORCA's Medusa were designed to meet.
The Medusa is an unobtrusive camera system that uses far red light, which is invisible to most deep sea animals. It is a lander platform,which allows it to be deployed in much worse sea states than those required for submersible ops. Ultimately, the Medusa is a new tool for observing life in the deep sea,capable of being deployed to depths of 6,000 feet and recording unobtrusively for up to 60 hours--a perfect complement to the submersible operations planned for this mission.
The Medusa was supposed to make a series of deployments along a transect approaching the Deepwater Horizon spill site, while the submersible operated at shallower depths collecting video and sediment samples. But as today has worn on the weather forecasts have grown increasingly dire, with predictions of 60-knot winds and 12- to 16-foot seas. So we are no longer WOW--we are running for shelter! With only two surface-to-bottom-and-back deployments of the Medusa, we must abort the lander's portion of the mission.
All of us on this expedition have spent a lot of time at sea, forcing us to become philosophical about such occurrences. A mission scrubbed because of bad weather is not a first for any of us, but it is still a tremendous disappointment.
These challenges of working on and in the ocean have made assessing the extent of the damage done by the Deepwater Horizon oil spill extremely difficult and have contributed to conflicting reports in the media. Our understanding of the complex web of life in the ocean is still limited by our all-too brief visits, which can be cut short at Neptune's whim. We must continue to seek new and better ways to explore, monitor, and protect life on our ocean planet.
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January 7, 2011
Mission Blue: Seafloor Dramas Unfold Before the Medusa’s Eye
On our second full day at sea, the Mission Blue: Survivors of the Spill team departs Roughtongue Reef for quieter waters near the head of the submerged Desoto Canyon. We drop the marine observatory Medusa to the bottom for the second time. Edie Widder of the Ocean Research and Conservation Association discusses what Medusa sees in the sea, and how.
By EDIE WIDDER
After the first dive yesterday, we were thrilled that Medusa came back, and it's generally working. There are the usual little tweaks that need to be made, and that was the point of this first deployment. But we can see stuff in the video Medusa captured: fish, a lobster, angelfish…
I always get a big kick out of observing the animal life down there unobtrusively. I think this is the most unobtrusive we could possibly be, so I feel as if I'm really peaking into their world and seeing how they live their lives when we're not down in the water messing things up.
This morning’s deployment was at the head of Desoto Canyon. That's where a lot of deep water sweeps up, possibly with some of the oil and dispersant in it. We have adjusted a few things and hope we'll get a sharper image and the best quality data that we possibly can.
It's a learning process, learning a new way of deployment from the ship. It was nice when we could take a device down with a submersible and line it up exactly on the area that we were interested in. But the point of this is to find a lower-cost way to have more access to the ocean.
We're getting a big dose out here of just how difficult access to that environment really is, especially for submersibles, because they've got a very limited sea state in which they can operate. But even with a system like medusa that you basically kick over the side of the ship there are still a lot of limitations, and it's frustrating.
When we were watching the team recover it yesterday, I was thinking of all these clever ways that we could have to recover it that would be much more efficient, but would require more money. That's always the problem.
The need for monitoring is huge. A lot of the damage that's been done in the ocean would not have happened if we'd had the kind of monitoring that we need. We have to know how our life support systems are being affected by what people are doing in pulling the very last fish out of the ocean at the same time that we're filling it up with our toxins and plumes.
Earth is a spaceship traveling through space. If you were going on a long space mission, the first thing you'd want to do is find out what your life support systems could withstand for the length of your trip, and you'd sure want to have the best monitoring possible to know that they were being maintained at peak performance the whole time. We're not doing that, and we really need to find ways to do it.
The Medusa is another way of trying to see into a world that is very resistant to our seeing into it.
The Eye in the Sea camera system, Medusa's predecessor, has been very exciting, far beyond my wildest dreams. I had this feeling that there had to be a lot of animals and behaviors that we weren't seeing because of the ways we were trying to observe. If you drag nets behind ships, there are a lot of animals that can outrun nets, that can see them coming. If you go down with submersibles and remote-operated vehicles, they have bright lights and noisy thrusters, and some animals are going to stay away from them.
How many animals are there in the ocean that we don't even know about because we've been scaring them away? If you think about it, the only reason we even knew that giant squid existed, something that enormous, was because they happened to float when they die. What about the stuff that doesn't float? We have no way of knowing that it's down there. That was the point of the Eye in the Sea.
Initially, I couldn't get any funding for it, because the funding agencies don't want to fund something unless you can tell them what you're going to discover with it. That was the point: I had no idea. I had to put the first systems together from bits and pieces, different funding sources. It actually started out as an undergraduate engineering project for the Harvey Mudd Engineering Clinic. We gave them pieces and they kludged it together. I got some funding from NOAA to put it in an underwater housing. The Monterey Bay Aquarium Research Institute paid for the battery and some of the early tests, which were critical.
Once we had something that was sort of working, we brought it out here, very near where we are right now. It was actually the Brine Pool, and I thought that's kind of like an oasis on the bottom of the ocean where I figured large predators might patrol.
The Brine Pool is one of the magical places on the planet that ought to be on everybody's bucket list, if only we could have submersibles for everybody! It's a lake underwater. You have to keep reminding yourself that you are underwater looking at a lake underwater, because it's this pool of brine that's so heavy it forms a pool on the bottom of the ocean.
This one is quite large, and it's got a coastline. It's surrounded by clams and mussels. There are symbiotic bacteria that can live off the methane that bubbles up through the Brine Pool. If you go down with a submersible and try to penetrate the surface, you can't, because it's too dense. You can push the manipulator arm through it, no problem, and it creates waves that sort of lap up against the shore. It's surreal, something straight out of science fiction.
Anyway, we put Eye in the Sea down there for the first time, and I had its camera programmed to go for four hours of background recording. Then we had this electronic jellyfish lure that I had developed that imitates certain bioluminescent displays. I had it imitating the pinwheel display of a deep-sea jellyfish. It's called the burglar alarm, and it's meant to attract the attention of large predators. If the jellyfish is caught in the clutches of a predator, its only hope for escape may be to attract something bigger that will attack its attacker. It's the same reason that birds and monkeys have fear screams: They're meant to attract the attention of large predators.
So four hours into the deployment, we activated the pinwheel display for the first time. 86 seconds after it came on, it recorded what was probably a six-foot-long squid that's so new to science it can't even be placed in any known scientific family. I certainly couldn't ask for any better proof of concept than that!
On the basis of that experience, I went back to the National Science Foundation and said this is what we'll discover, and they gave me sufficient funding to make the unit that went into the Monterey Canyon last year as the world's first deep-sea webcam. We actually have a year's worth of data from that webcam that we are hoping to have students help us analyze, because there's so much of it, we can't look at it all.
And now we've got the Medusa. The original Eye in the Sea could go down to 1,000 meters, about 3,000 feet. The Medusa can go to twice that depth.
This gives us an opportunity to do monitoring in some of Sylvia Earle's "Hope Spots." We need to find out, first of all, the places that are worth protecting, that need to be protected in order to make the Gulf healthy again. We can't do it all with submersibles, as we're dicovering out here. Remote-operated vehicles certainly help, but they're going to be scaring a lot of the animals away. If we want to understand the ecosystem, we need to look at it in as minimalistic a fashion as possible. That’s what the Medusa does.
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January 5, 2011
Mission Blue: Medusa To Deploy To Bottom Of The Gulf
By Edith "Edie" Widder
I've brought the Medusa deep sea observatory. It's a lander system that you can just throw off the back of the ship. It floats down to the bottom and settles there, and then it can record for two to three days. It uses the same principle as the Eye in the Sea camera system that I developed.
It uses far red light that's invisible to the animals. The idea is to be able to see without being seen. In this particular instance, one of the things we're hoping to see is six-gill sharks, because we've seen a lot of six-gills in the past using this kind of unobtrusive recording.
I'm very curious to see how they're doing, given the impacts of the oil spill. One of the things that we discovered using the Eye in the Sea is that they feed by slurping sand up from the bottom sometimes. That sand would likely have a lot of oil in it now.
To be able to record for hours and hours may seem long-term: With submersibles, we have incredibly brief visits that are fairly disruptive to the animals, because the white lights and noisy thrusters scare them away. This is better, but it's still not nearly long enough. That's the hardest thing to make people understand: With these very brief visits it's hard to get any kind of a sampling of what it was like before and what it's like now.
The system is stationary while it's on the bottom: It better not move, at least, unless there's a six-gill pulling on it--which actually has happened. That was with the old Eye in the Sea. We had a number of instances where we found that it tipped over, and we thought it was some kind of current. But no, now we realize that it was probably six-gills, because they can be fairly tenacious once they find the bait. Wanting to yank it, they yank the camera over with it sometimes.
Here's the great thing: The Medusa can go down to 2,000 meters. So we can go down to the depth of the spill site. The question is whether we will or not, because we have a lot of concerns about the currents and how bad they're going to be. It takes a long time for the Medusa to get down--it can take almost two hours. It could drift along the way, so we have some concerns. There's a certain amount of trepidation associated with throwing $70,000 worth of gear off of a perfectly good ship and just hoping you're going to see it again.
The way we retrieve it is we send an acoustic signal, and there's a transponder on the Medusa that responds by dropping a weight. We have 75 pounds of steel that will turn to rust and basically disappear eventually. We leave that on the bottom, and then it pops to the surface with its own floatation. We have a satellite beacon on it, so if we don't happen to be in quite the right place we can still find it.
The Medusa takes video, and it also has a CDT--so it's measuring conductivity, temperature, and depth. And it's got a light meter on it so it's measuring a profile of light penetration as it goes down.
This is the first time I've worked with this unit in the field, so there's more than a little trepidation. We deployed it once in a lagoon at very shallow depths just to work the kinks out. But this is its first open ocean deployment. We are going to put it in at a depth where, if it didn't come back, the Deepworker could reach it and hopefully help retrieve it. That gives us a sense of reassurance for this first deployment.
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