2015 Summer Internship Program
Cross Isobath Exchange in Bering Canyon
This summer I worked for NOAA researching cross isobath exchange in the Bering Canyon. Oceanographers Carol Ladd, Wei Cheng, and Al Hermann shared data with me that they had collected from 4 moorings in the Bering Sea and over 40 stations sampled throughout the year 2014-2015. The goal of our project was to learn more about how water reaches the Bering Shelf, where it comes from, and what kinds of things it brings onto the shelf. The Bering Shelf is the largest fishery in the United States, and it is important to learn more about its nutrient sources and larval transport onto the shelf.
The first portion of the project focused on using a regional ocean modeling simulation to reproduce ocean dynamics. The model runs went from 2007-2013, and I used Ferret to compare model output to the observational data. I generated plots of temperature and salinity that allowed us to see the bias between model and data which could then be used as model validation. We found that the model tended to predict colder and saltier water than the data, which can be attributed to the fact that most of the water circulating onto the shelf is land derived and comes from cold glacial lakes.
At the end of the project we began running simulations looking at ocean current versus temperature, salinity, and current strength, respectively. This helped us see on a map that warm currents, especially the Aleutian North Slope Current, are responsible for much of the water that ultimately reaches the shelf. Future directions for the project include closing off Unimak Pass in a model simulation for comparison purposes. This kind of experiment would tell us how blocking Unimak would influence shelf water flow.
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