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Alaskan Oceans:
Temperature and Salinity
Elizabeth Litwin
Introduction
The coast of Alaska, one of the longest in the world, is
bordered by many large bodies of water: the Pacific Ocean,
Gulf of Alaska, the Bering Sea and the Arctic Ocean. By
comparison, Massachusetts is only bordered by the Atlantic
Ocean. Because of this amazing difference, I became
interested in studying the ocean waters of Alaska, also
known as oceanography. I became involved with this project
as a member of the Young Explorers Team that went on the
Harriman Expedition Retraced in Summer 2002.
As I learned more about oceanography, I became more
interested in salinity and temperature. Although I
understood the idea of temperature, I was less familiar with
the idea of salinity. After doing some research,
I found out that salinity is the amount of salts in one
kilogram of water. Since I was going to be traveling the
coast of Alaska by ship, measuring salinity and temperature
seemed like a logical thing to do for a project. These two
measurements are closely connected. In a laboratory, the
hotter water gets, the more salt can be dissolved in it.
Using this idea, my project question is, Is the
salinity higher in the warmer Southern waters of Alaska
compared to the colder Northern waters? As our ship
traveled north toward the Arctic Ocean and the water got
colder, does salinity go down?
Methods
Collecting salinity and temperature data was actually a
lot of fun. The first thing that I had to do was make data
sheets and put them in a book. The information that had to
be collected on each sheet was the date, time, location,
salinity, and temperature readings. Although there are three
temperature layers of the ocean, my project focused on the
surface layer. To do this, each time the ship anchored I
asked a crewmember to help me get a bucket of water off the
stern. The crew was always helpful and seemed interested in
what I was doing.

Measuring salinity and
temperature
Once the bucket was on the stern, I used a Palm Pilot
with a temperature and salinity probe to gather my data.
Each reading was entered into my data book. I also took
water samples at each location by putting sea water in a
clean plastic bottle and labeling it. I analyzed my data
first by making a spreadsheet based on each location that I
collected data. Then I used a chart wizard software program
to make the charts.
Results
Table 1 shows the 32 locations where salinity and
temperature measurements were taken.
Table 1 - Salinity and
Water Temperatures
LOCATION
|
SALINITY
|
H2O
TEMP
|
Metlakatla
|
27.7
|
51.03
|
Wrangell
|
12.2
|
51.26
|
Juneau
dock
|
15.2
|
50.17
|
Skagway
dock
|
4.2
|
47.72
|
Sitka
dock
|
27.4
|
55.90
|
Yakutat
dock
|
27.0
|
57.00
|
Kayak
Island
|
29.7
|
56.64
|
Cordova
dock
|
27.1
|
51.26
|
Valdez
|
5.4
|
43.82
|
College
Fiord
|
27.2
|
40.64
|
Harriman
Glacier (Face)
|
3.3
|
36.98
|
Harriman
Glacier (1.5 mi out)
|
13.9
|
42.60
|
Latouche
Island
|
24.1
|
58.47
|
Kenai
islands
|
24.6
|
51.39
|
Kenai
Fiord
|
24.3
|
57.61
|
Kodiak
dock
|
31.3
|
53.34
|
Kukak
Bay
|
25.4
|
59.08
|
Chignik
|
31.0
|
54.80
|
Unga
Island
|
32.7
|
52.73
|
Otter
Cove
|
32.8
|
53.71
|
Dutch
Harbor
|
34.6
|
51.51
|
St.George
|
33.7
|
47.11
|
St.Paul
|
33.6
|
48.09
|
St.Matthews
|
33.7
|
43.45
|
Hall
Island
|
33.8
|
45.65
|
St.Lawrence
|
33.2
|
45.53
|
Teller
|
19.2
|
50.17
|
Little
Diomede
|
34.4
|
40.52
|
Cape
Dezhnev, Russia
|
28.5
|
39.55
|
Lorino,
Russia
|
30.4
|
41.74
|
Itygran,
Russia
|
34.0
|
38.94
|
Yanrakino,
Russia
|
32.5
|
43.94
|
Chart 1: Southeast/Central, sample
points 1-8. The average temperature was 52.6 dgF. The
average salinity was 21.3 ppt. Wrangell, Juneau, and Skagway
all pulled down the average salinity. These three locations
are within the Inside Passage and they are influenced by
water coming from land. Each is right next to a freshwater
river. All the other locations are more effected by the
ocean. The temperatures are all about the same.

Chart 2: Prince William Sound,
samples 9-12. The average temperature was 41 dgF. The
average salinity was 12.5 ppt. I removed these sample points
from the Southeast/Central samples because they are so
different from the other areas. Prince William Sound is
surrounded by many large glaciers that empty into Prince
William Sound. Glaciers are freshwater sources that make the
salinity drop. The temperatures are also lower then chart 1,
because glaciers are colder then average ocean water.

Chart 3: Central/West, samples13-21.
The average temperature was 54.7 dgF. The average salinity
was 29 ppt. Compared to chart 1 and 2, the salinity and
temperatures shown in chart 3 are steady throughout the
Central/West region. All of the locations are influenced by
the waters of the Gulf of Alaska and Pacific Ocean. However,
the salinity gradually increases as the sample locations
move west, farther away from glaciers of the Kenai
Peninsula. Compared to charts 1 and 2 the temperature also
increases as the influence of glaciers decrease.

Chart 4: Bering Sea, samples 22-32.
The average temperature was 44.1 dgF. The average salinity
was 31.5 ppt. The pattern in chart 4 is steady like chart 3,
except for sample 27, Teller. Tellers bay is enclosed
by a long sandbar that traps freshwater coming from the
land. As a result, the salinity drops and the temperature
goes up. Salinity is higher in chart 4 then in any other
region. This is because glaciers do not influence this area
the way they do in all the other regions. This region has
the coldest temperature except for Prince William Sound that
is heavily influenced by the cold glacier water.

Chart 5: A comparison of salinities
and temperatures by the regions described in Charts 1
through 4.

Chart 6: A comparison of sample
locations that have been influenced by freshwater/glaciers
(Wrangell, Juneau, Skagway, Valdez, Harriman Glaciers, and
Teller) to locations that are not heavily influenced by
freshwater. It is clear that freshwater and the cold water
of glaciers causes the salinity and temperature.

Conclusion
My original question was, Is the salinity higher in
the warmer Southern waters of Alaska compared to the colder
Northern waters? My data actually shows the opposite.
In Chart 5, you can see that in the more northern areas of
Central/West and Bering Sea, the salinity increases. This is
because the environment affects the salinity and temperature
in many different ways, unlike a laboratory experiment. I
found that glaciers and freshwater rivers heavily influence
salinity and temperature regardless of whether you are in
the north or the south (Chart 6). Wrangell, Juneau, and
Skagway (Chart 1) are and Teller (Chart 4) places where
freshwater has a big influence. Freshwater from glaciers had
a big impact on salinity in Prince William Sound (Chart
2).

Calving glacier

Glacier ice cubes
It is clear that the different shapes of land affect the
salinity and temperature. The Inside Passage, Prince William
Sound, and Teller (Chart 1, 2, 4) are all land shapes where
fresh water coming from the land gets trapped and does not
get mixed up with the more salty ocean water. In the
Central/West region and Bering Sea (Chart 5) the shore is
directly on the ocean and the salinity is higher. So, there
are three things that influence salinity: the amount of salt
that can dissolve in water, the amount of freshwater that is
put into the ocean water, and the shape of the land
surrounding the water.
Bibliography
Bartsch, Paul, et al. A Bibliographical
and Short Biographical Sketch of William Healey Dall.
Washington, D.C.: Smithsonian Institution, 1946.
Foresman, Scott. Science Insights:
Exploring Matter and Energy: Addison Wesley Longman, Inc.,
1999.
Hill, Amy, Marine Biology, An
Introduction to Ocean Ecosystems. Maine: J. Weston
Publisher, 1995.
Norcross, Brenda, Professor of Fisheries
Oceanography, Institute of Marine Science Alaska Fairbanks.
Unpublished communication, July 2001.
Pearson, Roger and Hermans, Marjorie,
eds. Alaska in Maps: A Thematic Atlas. Fairbanks, Alaska,
Institute of the North, University of Alaska,
2000.
Peckol, Paulette, Professor of Marine
Biology, Smith College. Personal communication. Unpublished
communication, February 18, 2002.
White, Virginia, Chemistry Instructor,
Smith College. Unpublished communication, February 18,
2002.
Wockley, Melissa, Teacher of Marine
Biology, Williston Northampton. Unpublished communication,
spring and summer, 2001.
World Wide Web Sites
Chamberlin, Sean. The Seasonal
Thermocline and Its Effect on Phytoplankton
World Wide Web, Oceans on Line. National Oceanic and
Atmospheric Admistration.
Office of Naval Research. Ocean
Water: Salinity, Focus Ocean Web site.
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