Mail Buoy
June 6, 2003
Hi. My name is Shama Pathan.
I live in Lexington, Massachusetts and currently attend Jonas Clarke
Middle School. I am in the 7th grade and my science teacher, Ms.
Shield, asked her students to email your adventurous crew. I just
wanted to know if there has ever been a leak on a submarine or
ship (or whatever type of transportation you use in the ocean)?
Hi Shama, thanks for writing. Fortunately, there's never been a
leak during operations. But that doesn't mean they've never occurred.
Every three years or so, Alvin is entirely taken apart and then
put back together with any degraded parts replaced or repaired.
After each reassembly, the sub is put in shallow water (10 meters
deep or so) to test it. At times, during these practice runs, leaks
have occurred. Of course, the problem is addressed before further
practice and then more deep-sea dives.
Great question!
Joe Appel
Dive and Discover writer
Hello!
Wondering if there is anyway to bring up your specimens alive?
A special pressurized container?
Cindy Shyne
Dear Cindy,
Thank you for your very interesting question. Animals often arrive
at the surface alive, especially if we keep them in cold water
on their way back to the ocean surface. We use insulated boxes
on Alvin's basket to keep the water cold while the animals make
the transit up with Alvin and back on to the ship. As soon as the
animals arrive on the ship with Alvin, we put them in cold water
similar to temperatures they experience on the seafloor. Yes, pressure
chambers have been designed to keep deep-sea animals alive so that
we can study them. The chambers can be very expensive to construct.
The cost of maintaining an animal alive for long periods of time
(months) can also be expensive. Food and often fresh sea water
have to be given in very specific amounts. Scientists who study
how animals work, for example, identifying the chemicals in the
blood or how much they "breathe" (respire) under high
pressure, will use such pressure chambers.
Thank you again for your question.
Dr. Tim Shank
Cruise biologist
I'm from the USA, and my
question is: Since there has been so much precipitation in the
USA the past 8 months or so, does that affect the climate/condition
of the sea and sealife? Does it dilute the ocean's "saltiness" at
all?
Hi Sheila,
My name is Jeff Mendez, I am a scientist on the Atlantis. You have
a great question, that I am sure many people wonder about. The
key to answering it is to remember that the water forming clouds
comes from the ocean itself. This is the cycle of water. Water
is evaporated from the surface of the ocean, until it reaches a
point where so much water is in the air that it precipitates out.
This water then washes across our streets and sidewalks until it
can soak into the ground. The water will travel, sometimes as deep
as a mile underground, sometimes just inches underground. This
water may form creeks which combine to form rivers, eventually
emptying into the ocean.
Scientists can measure the saltiness of the ocean near these river
outflows... and we can tell that the surface water of the ocean
is much more fresh than the surrounding ocean. Large rivers like
the Amazon or Mississippi have large "plumes" of fresh
water sometimes extending hundreds of miles into the ocean from
the their mouths. Because fresh water is less dense than salt water
these plumes stay at the surface until they diffuse into the ocean.
In times of intense rain these plumes are larger and occur at the
smaller rivers. When it rains over the ocean only the very top
foot or so is diluted (but only a tiny bit). These fresh water
plumes do not last long, and are diluted into the ocean where the
cycle begins again.
To directly answer the question, yes rain can dilute the saltiness
of the ocean, but only at the surface, and for the most part only
near mouths of rivers. Just to give you an idea of the volumes
of water involved: The ocean is approximately 1,000 quadrillion
quadrillion gallons (this is a 1 with 27 zeroes after it, or 10^27).
The flux of a large river is only 1 quadrillion gallons a day (10^12),
of which there is only 1 part river in 1,000 quadrillion parts
ocean. All this is to say the fresh water is a very small amount
compared to the ocean.
Does that affect the climate/condition of the sea and sea life?
Sea life in the ocean is not affected by pure fresh water that
washes into the ocean. But the pollutants that wash off our streets
and waste centers do affect sea life to a large extent. If you
have been staying tuned to the website you know that rain makes
the sea very rough. It is difficult to do much work when there
is a storm; we normally stay inside and wait for the winds to die
down and the sun to come out. But if you are below the surface
it is not noticeable, and very calm. Only the very surface of the
ocean is blown about by the winds and rain.
Hope this helps,
Jeff
What is the biggest volcano (if it has a name), and what is its
size? Are there are signs that any volcanoes may be active?
Sharon Wood
Koro Public School
Australia
Hi Sharon,
Due to poor imaging of the seamounts, it is difficult to say which
of the ancient volcanoes has the greatest mass. However, Gregg
Seamount comes withing ~800 meters of the sea surface and may qualify
as the tallest seamount. The easternmost end of the New England
Seamounts may be active. The seamount, called Great Meteor, has
been dated poorly (plus or minus a few million years), so it is
not known if Great Meteor is active (although I may have the answer
in several years when I complete my thesis!).
Take care,
Matt Jackson
Cruise scientist
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