Just as meteorologists forecast the behavior of the atmosphere, scientists are using the information gathered from the PWSOS to predict the behavior of the ocean waters of the Sound and the waters that flow through it.
A research team headed up by Dr. Yi Chao from the Jet Propulsion Lab and including Dr. Xavier Capet from UCLA. have developed a Regional Ocean Modeling System (ROMS) for PWS which can simulate the behavior of currents, tides, salinity, and temperatures. Eventually, the model will also monitor biogeochemical cycles and ecosystem functions in PWS. The model uses a set of equations to approximate the behavior of the ocean at any given time during the year. The oceanographic research group is gathering data for this model from PWS and the entire Gulf of Alaska.
"If we want to model what is going on inside the Sound properly, we need to know what is going on outside the Sound," Capet said.
The group has created three scales of measurement, with the largest measuring the Gulf of Alaska, and the smallest focused on the Sound. As the area of measurement decreases, the resolution increases to as little as 1.2 square km. In 2005, the research group focused on modeling the Pacific Ocean and the Gulf of Alaska. Once the kinks have been worked out of the equations based on the large-scale movements of the ocean, the group will focus more of its energy onto the small scale, high-resolution simulations of PWS.
The preliminary studies that have been done in the Sound support other scientists' theories of a stable counter-clockwise gyre that is particularly strong in the summer. It also clearly shows the movement of a warmer current from the south as is passes along the coast in the winter. Most importantly, what the model shows is that conditions in the Sound vary greatly from one location to another, and also vary greatly from one time to another.
"There is a significant structural variation, spatial and even temporal, in the Sound," Capet said. "I was very surprised to see there was this sort of variation."
The high resolution of this model takes into account that variability, and will be able to accurately forecast the condition of the ocean with respect to surface currents, tides, temperature change, and mixing. The model will also be able to track nutrients or pollutants as they cycle through the water. With the addition of the ROMS model to the PWSOS, knowing the strength of the currents on any given day may become as easy as knowing whether or not it might rain that day.
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