Lake
Superior
Research
Cruise
on
board
the
Blue
Heron
Large Lakes Observatory
University of Minnesota - Duluth
May 27 - June 3, 2010
Background: I spent my sabbatical from Creighton University working at
the Large Lakes Observatory (LLO), part of the University of Minnesota,
Duluth. Most of the sabbatical (January - August 2010) was spent
in the laboratory of Dr. Liz Minor, a chemistry professor at UMD.
I studied two extraction disks used to collect and concentrate
dissolved
organic matter from natural waters. During the research cruise
pictured below, I was able to use these two different disks at the
various mooring stations that are maintained and operated by
UMD-LLO. These pictures capture some of the activities that took
place during the cruise.
The
Blue
Heron is the 86-ft research vessel operated for the
Large Lakes
Observatory, University of Minnesota - Duluth. The ship has a
5-person crew and can accommodate six scientists. It can go 20
days or 3000 miles between port calls. Inside the ship on the
main deck level (just forward of the open rear deck in the picture) is
the wet lab where my lab station was located. Forward of
that is the galley and then the bunk area. The upper deck
contained the pilot house and a lower deck features a dry lab, computer
work station for the scientists, and the engine room. Photo by
Bruce
Groehler, UMD photographer.
Standing in front of the Blue Heron at dockside. We had a day to
load
our equipment and set up our lab areas for the cruise.
Lake Superior off the bow of the Blue Heron. The lake has many
moods and personalities, some of which make the ship seem even smaller.
Under all this water lie the remains of nearly 400 commercial ships,
all much larger than the Blue Heron, that have sunk in the past 140
years.
Overview
of
my
project:
1. Water samples were collected from
specific locations and depths.
2. The samples were filtered through a 0.70 um filter to remove
particulate organic matter, leaving dissolved organic matter.
3. This filtered water was then extracted with the specialty disks.
4. I then recorded the UV-vis of the resulting filtrate (on board) and
later, back in the lab, of the material retained on the disks
(retentate).
The ship stopped at a series of seven existing moorings: Here, the
water sampler is being landed on deck after
collecting water at a specified depth.
Water sampler being emptied into various sample containers. Under
the cylinders, note the electronic equipment that detected temperature,
conductivity and depth. Pictured at left are Lindsey
and Annie (from
Virginia Commonwealth University) and Prosper, a graduate
student at UM-D, LLO.
For several experiments, water was filtered through a 0.7 um filter,
our working cut-off between dissolved and particulate
substances. In the picture above, water is being transferred to a soda
canister where is then forced by compressed nitrogen through the glass
fiber filter. The water I studied was filtered in this
way
because I was interested in measuring dissolved organic matter.
Pictured is Hongyu, a graduate student (L) and Dr. Liz Minor, of the
Large Lakes Observatory (LLO) and UM-D Chemistry. My sabbatical
was spent working in her lab at LLO.
Here Hongyu is filtering water late at night. Filtering had to be
done as soon as possible after collection. The air temperature was
about 38 oF (3.5 oC) at night in the middle of the lake -- the same as
the lake! Note
that the life jackets had refective strips so it would be easier to
locate a person overboard in the dark.
Me at my lab station on the Blue Heron with two filter rigs. I
had a porthole to the right in the photo so I had a nice view of the
lake
at all times. The lab was cool because the large door to the deck
was always open. The
purple gloves are intended to keep skin oil away from the water
samples. Lake Superior is an extremely clean lake and oils from
skin would contribute to the amount and type of organic materials
measured.
My cool window in the lab. The gloves didn't make using the laptop
mouse any easier! (Note: the computer was duct-taped to the benchtop.)
Filter rig: In my experiments, I filtered 5 L samples of lake water
through expensive extraction disks manufactured by 3M. The
extraction disk at left looks discolored because it contains all of the
dissolved organic matter that was trapped by the disk.
The label: The "3" refers to this being the third research cruise Dr.
Minor's group has taken to these locations. The "NM" refers to
"Northern Mooring" (in Ontario waters of Lake Superior). The "XC"
refers to the 3M extraction disk I was using, and the hatch marks was
my way of keeping track of how many liters of water I had passed
through the filter rig (I had another way as well). In the picture at
right, the same disk is shown
after the trapped organics were extracted with methanol. This
leaves the disk looking much lighter in color. The extracted
organic materials were analyzed.
Here I am at the UV-vis spectrophotometer that we took with us.
Note how the instrument is tied to the table with cording to prevent it
from sliding off the table in high seas. Note also how I held the
sample bottles upright behind the cord. This prevented tipping,
falling, and rolling. For most of this trip, the seas were
reasonable, although I quickly learned how to use my hip along with my
legs, spread apart, to make a tripod for stability, especially useful
when pouring liquids.
Old Glory on Memorial Day. At left, the water sampler and at
right, the core
sampler (samples the lake floor)
Other
experiments. In the following pictures, some of the other
sampling techniques used
by the other scientists are shown:
Here the core sampler (returns cored samples of the lake floor) is
being lowered into the lake.
Here the core sampler is returning from a visit to the bottom of the
lake
where it collected samples of the lake bottom. The water is so
clear
that one can see the sampler through 30 feet (10 m) of water.
Mud from the core sampler is being removed from the core tubes.
Note the sampler in the background.
This is a sediment trap used as part of a long-term experiment
(months). As sediment slowly sifts to the bottom of the lake, it
is caught in the yellow cone and collected in one of the bottles at the
bottom. Every two weeks, for example, the bottle carousel
advances to a new bottle. The sediment trap is set on one cruise and
collected on another. On this particular cruise, the sediment
trap was
recovered from a mooring damaged during the winter of 2009-10.
A plankton net.
Prosper using a filter rig. Filter rigs are used for a variety of
projects.
The ship and crew.
This is Captain Mike in his pilot house explaining something about the
ship's
capabilities. We were welcomed to visit the pilot house and
Captain Mike was always interested in our projects and how they were
going.
This is a view from on the back deck, looking forward toward the lab
area. Note several differences between this research cruise and
a typical Caribbean cruise. (I never found the pool deck, ballroom, or
the shuffleboard courts, however, the dining was exceptional!)
Just like at home, everybody gathers around the kitchen table (ooops,
galley table)
Kathy, one of the four crew members, served amazingly satisfying and
delicious meals! She and the other crew members had a delightful
sense of humor and were wonderful hosts. (Next time I will do
something with my hair before pictures!)
Here are two bunks. Each had curtains for privacy. My bunk
was the top one and I tried hard not to step on John in the lower bunk
getting in and out of the bunk.
This is a rare photo where some of the crew seem to be relaxing.
Standing is Captain Mike (left), and Justin, the ship's technician
(from the LLO) and Rual
(sitting). The nice weather must have brought them to the
deck.
Flying the colors.
Here I am on deck on a particularly nice morning.
Sonar tracks the lake bottom.
No cruise is complete without a visit to the engine room. Note
the ear protection. Rual was the guide and the tour was
conducted entirely with gestures. The
engine was 775 horsepower, got 2 gallons to the mile and cruised at 9
miles per hour.
The research group.
Our research group on deck. From left: Me, Annie (a collaborator
from Virginia Commonwealth University), Hongyu, Liz and Prosper.
One other scientist, Lindsey, is not pictured here; with sampling at
anytime during 24
hours, it was hard to find everyone awake at the same time. In
this picture I am just getting up (note coffee), while Prosper and
Hungyu are ready for bed after being up all night.
Lake Superior and its incredible beauty.
Out my lab porthole.
Gray seas with a storm approaching.
Sunset over Michigan's Keweenaw Peninsula (known to the locals as the
U-P where the residents call themselves "Yoopers").
Almost home.
At the end of the cruise: Heading into Duluth's shipping canal and
under the Lift Bridge.
Acknowledgments.
My sabbatical has been a great
experience, with the highlight being the research cruise on Lake
Superior. I wish to express my gratitude:
to the Creighton University College of
Arts and Sciences for providing sabbaticals.
to Dr. Liz Minor for hosting me as a visiting professor in her research
lab and for providing an interesting project for me.
to the students in Dr. Minor's group, specifically Brittany, Meg,
Prosper, Hongyu, and Melissa (from Dr. Werne's group) for teaching me
many of the techniques I used.
to the faculty and staff of the Large Lakes Observatory of the
University of Minnesots, Duluth for making me feel most welcomed.
I especially enjoyed lunches with them and the graduate students.
to Dr Josef Werne, whom I've never met, for allowing me to use his
office while he was on sabbatical in Australia.
to the crew of the Blue Heron, Mike, John, Kathy, and Rual, for making
my cruise experience the highlight of my sabbatical.