I continued this interest after moving to Alaska as a Ph.D. student, and actually wrote my dissertation on the nitrogen cycle of a small interior Alaskan lake. However, at the same time I started working on sea ice-related ecology in the coastal Beaufort Sea, at the northernmost point of Alaska, and later switched my primary interest to the Bering Sea. The Bering Sea is extremely rich in species, both in numbers and diversity. It turns out the answer is that sea ice plays an important role in the ecosystem, and increases, rather than decreases, the productivity. Now, with a trend towards reduced sea ice, the system is undergoing major changes.
Sea ice affects the system at many different levels.
For example, some mammals absolutely depend on sea ice for survival. The polar bear cannot hunt effectively in the absence of ice, and it primary prey, the ringed seal, only dens in sea ice and feeds primarily on arctic cod, which again is dependent on ice. The best route to a career in marine science, including arctic work, is to pursue a strong science undergraduate degree. While doing this, you can take advantage of intern opportunities during the summer. For example, the Alaska Sea Life Center in Seward offers summer internships to undergraduates, who learn to work with seals, sea otters, sea lions and marine birds.