|
 |
Astrid Schnetzer
Postdoctoral Researcher |
|
|
What is the average temperature and salt level at the hydrothermal vents? Student
Name: Kris
State: WV Country: USA
|
|
| |
|
The temperature right at the vent can be as high as 450 deg C but the water cools off very quickly as soon as it gushes out of the chimney and mixes with the ambient water that is only 2 deg C. The salinity in deep water is about the same as that of vent fluid after it is released from the smokers (here at the East Pacific Rise it is about 34.6 ppt (parts per thousands)). Many changes in salinity are measured for vent fluid while it is still inside the earth crust. |
|
|
|
|
Do your ears pop when you go down to the bottom of the ocean? Student
Name: Audrey, CCD
State: OH Country: USA
|
|
| |
|
No, the pressure inside the sub stays approximately the same because the core of the submarine -- where the scientists and the pilot sit -- is made out of Titanium that withstands the pressure. |
|
|
|
|
How quick does it get cold when you are going down in the Alvin? Student
Name: Kyle
State: OH Country: USA
|
|
| |
|
It takes quite a while till you feel the temperature drop. We put our pullovers on at about 1000m depth after we descended for approximately 1 hour and 15 minutes. |
|
|
|
|
What sort of toxic chemicals come out of the vents? Student
Name: Thomas
State: OH Country: USA
|
|
| |
|
The substances that are generally toxic to larger animals that come out of the vents include hydrogen sulfide and several metal sulfides (iron, zinc, copper). Vent organisms have found a way to deal with the higher concentrations around the vents and scientists are beginning to understand the mechanisms they use to detoxify their tissues from these chemicals. |
|
|
|
|
Why is the pressure so much greater in the deep ocean than on land? Student
Name: Katie
State: OH Country: USA
|
|
| |
|
The pressure at depth is due to the millions of gallons of water that weigh on objects at depth. The amount of the water above you (and its weight) increases with depth and therefore pressure increases. |
|
|
|
|
Hi, I am wondering how do bioluminescent fish produce light? Thank you for your time and please answer my question. Student
Name: Alex
State: CA Country: USA
|
|
| |
|
The fish do not produce the light themselves but they harbor bacteria in bioluminescent organs (photophores) that produce light. The bacteria contain an enzyme called luciferase which reacts with a protein called luciferin as soon as oxygen is provided. During this process energy is set free in form of light. Some studies have shown that the fish can control when the bacteria glow - but how exactly they do that is not well understood. |
|
|
|
|
How does bacteria help the Pompeii worm? Student
Name: Nisarmegnice
State: CA Country: USA
|
|
| |
|
That is a great question and scientists are working hard to find out how the worm might profit from the bacteria. There are 2 theories - one is that the bacteria might function as a heat shield for the worm since most bacteria are located at the hind end of the worm where the temperature is highest when the worm hangs out in his tube. The other theory is that the bacteria might help to get rid of high concentrations of toxic chemicals such as hydrogen sulfide. Hopefully in the near future we will understand this relationship much better. |
|
|
|
|
Was it fun getting jell-o poured all over you? Do they do that to initiate all of the new divers? What exactly do you do for the team? Student
Name: Amelia
State: ID Country: USA
|
|
| |
|
The warm jello was actually a nice change after being showered with ice cold water. Everyone who gets to dive with Alvin for the first time is being showered with cold water, jello or sometimes more unpleasant things like tomato juice. My work on this cruise is to collect protistan samples from the hydrothermal vent sites. Protists are tiny creatures like ciliates or flagellates and we hardly know yet how many are present at the vents and what role they play in vent communities. |
|
|
|
|
What is life really like onboard a research vessel? Student
Name: Natalie
State: IL Country: USA
|
|
| |
|
It is very busy and often you live very irregularly. Sometimes you spend most of the night with an experiment and sleep during the day and then it turns back to normal again. All the scientists that come from several different labs and institutions get the chance to talk about their research and sometimes new working groups form. When the work is done people go and watch movies or they play ping-pong. Overall everything shapes around the work schedule and around breakfast, lunch and dinner as long as the sea stays calm. You can also do laundry on board and have a cup of tea outside on the back deck. |
|
|
|
|
How long have you been doing your research? Student
Name: Luis
State: IL Country: USA
|
|
| |
|
I have been working in oceanography and marine biology for 9 years and can't believe how fast the time has gone by. During these 9 years I have worked in the Mediterranean Sea, the Sargasso Sea (Northern Atlantic), the coastal Pacific, the Southern Ocean and now the deep sea. I have met the most interesting people and could not imagine a job that I like better than this. |
|
|
|
|
Why didn't Fried Freddy break because of the pressure? Student
Name: Bob
State: OH Country: USA
|
|
| |
|
Fried Freddy was not crushed because the pores in its shell allowed the pressure inside and outside to reach an equilibrium. |
|
|
|
|
How can fish stand all the pressure under the water and we can't? Student
Name: Aaron
State: WV Country: USA
|
|
| |
|
Many deep sea fish are well adapted to pressure. Their bodies have a much higher water content than ours with > 90% in comparison to ~ 60% in humans. Water cannot be compressed and therefore these animals are okay with high pressure. Also our organs are filled with air (lungs, stomach, etc) and this is not the case with fish at depth. Most deep-sea fish don't even have a swim bladder anymore. Since air gets compressed very strongly with the increasing pressure at depths, our lungs would collapse. |
|
|
|
|
How early do you get up to start the day? Student
Name: Kaylea
State: WV Country: USA
|
|
| |
|
It depends on what type of work needs to be done that day. Usually I get up around 6:30 or 7:00 a.m but sometimes I get water samples from 2500m depth late at night and those need to be processed right away. This often takes until 6:00 am and then I sleep during the day until about 2 p.m. |
|
|
|
|
What kinds of things do you have to plan to go on an expedition and how do you fulfill those plans? Student
Name: Samantha
State: NC Country: USA
|
|
| |
|
The most important thing is that you formulate a clear and unique research question. For that you need to do your homework and read up on the work of other scientists that studied the same habitat or organism. If your hypothesis is formulated you need to figure out how to go about testing it. For example: if your hypothesis is that animals in the deep sea respire slower than those in surface water, then you need a way to measure respiration in both places to compare it. The next thing is to make a long list of materials and chemicals that you need for your measurements and experiments. It is always a good idea to have backup equipment in case something breaks or to have extra materials with you. And last but not least you should always have one or two more ideas or hypothesis that you can work on just in case the organism that you wanted to work on is nowhere to be seen. Since it is nature you never know who will be there for the rendevous. |
|
|
|
|
What is the most facinating thing you have discovered about they hydrothermal vents? Student
Name: Casey
State: WI Country: USA
|
|
| |
|
How diverse the environment at and around the vents is. There are diffuse flow zones, white smokers, black smokers, old inactive zones of huge basalt lobes, sulfide rocks, bacterial mats in white….. As soon as you fly around at the vents the landscape changes a lot and in each of these microenvironments you find several vent organisms that like it best there. |
|
|
|
|
What would an animal from the sunlight zone need to live in the midnight zone? Student
Name: Conner
State: CA Country: USA
|
|
| |
|
If a critter from the surface came to live in the lightless zone it would need to be able to rely on other senses than the eyes. That could mean they grow very long wiskers or they evolve to produce their own light (bioluminescence). They would also have to adapt their metabolism to the colder environment down below, which might be accomplished by having different metabolic pathways or by simply growing a thick layer of fat. Many of such adaptations have taken place throughout evolutionary time scales (milions of years). Sometimes you can even see changes within the lifetime of an animal, if that animal lives in the surface water as a larvae or juvenile and then drops deeper and deeper while it grows to become an adult (eg, anglerfish). |
|
|
|
|
Are there currents in the midnight zone? If so, what affect do they have on organisms that live there? Student
Name: Sophie
State: CA Country: USA
|
|
| |
|
There are currents throughout the water column including the zones where there is no more light (aphotic zone). You generally find 2 groups of animals in the water: the plankton and the nekton. Both words are from the Greek language and plankton means "the wanderer". Plankton are all the animals that are moved by currents and they are too small to swim against them like jellyfish, many crustaceans or comb jellies. While the currents transport these organisms horizontally they can often sink or ascend as they please. So, if these critters want to generally stay within the same area they can ride the surface currents in one direction (e.g. North), sink and ride the opposite deeper current back (e.g. South). Sometimes currents take these critters too far like you can see when jellyfish strand on the beach. Nekton summarizes all the animals that can easily swim against most large ocean currents like fish, octopus or shark. |
|
|
|
|
What was in the large water sampler and what were the results of your findings?
When is the next expedition scheduled? Student
Name: Andrea
State: MD Country: USA
|
|
| |
|
The large volume water sampler is used by my colleagues Shannon and Shellie and its main components are a pump, hoses, a battery and 2 large bags inside 2 boxes. All these parts are mounted onto a platform and this platform sinks to the seafloor due of the heavy weights attached to it. At the seafloor the Alvin positions the sampler so that it collects hot water into the bags from right near the vent. When the bags are filled (120L), the weight is released and the floats - that are attached on top - make the platform ascend to the surface where it is collected by the Atlantis. The water is then used to determine the number of microorganisms at the vents and preliminary data show that there are more viruses and bacteria in the hot water of the vent than in the deep water surrounding the vents. This is the last Extreme cruise that Dr. Cary has planned within his ongoing project. New expeditions will follow but we do not yet know when. |
|
|
|
|
I am doing a project in oceanology on phytoplankton. What is the most common phytoplankton found in the deep sea, where you are exploring in Alvin? Student
Name: Lee
State: CT Country: USA
|
|
| |
|
There are no phytoplankton in the deep sea because they need light for photosynthesis. Phytoplankton are restricted to the upper ~100 m of the water column were the light still provides enough energy to fix carbon. But phytoplankton belong to a group called protists and other members of this group like ciliates or flagellates we do study at the vents. Since we are only starting to learn about protists at vents I am not able to tell you yet which species are the most common, but we hope to find out after bringing all the samples back to our lab. |
|
|
|
|
What would your advice be to a young person who has an interest in pursuing Marine Biology as a career? Student
Name: Michael
State: CT Country: USA
|
|
| |
|
To never let anybody else tell you that what you are interested in cannot be done. I come from a landlocked country and there were several people who did not understand why I wanted to become a Marine Biologist -- I do not want to trade this job for any other. I was very fortunate to come across wonderful advisors throughout my career and I tried to learn from them the best I could. So my advice is look out for good mentors that share their knowledge and help you to become independent. |
|
|
|
