Dennis Walikainen W hen Sarah Green discusses her research on Lake Superior, she speaks in hushed tones, as if she were letting us in on some huge secret. In a way, she is. Lake Superior has been a relative unknown, at least in the research world, until now. Noel and Erik will be able to date the sediment to see how fast things are depositing, and Charlie will be looking for resting zooplankton eggs, which wait for a storm to come along, resuspend them and make them hatch, even though they may be have been sitting in the sediment for many years. The researchers will also be looking at the history of productivity in three different areas, taking cores off Ontonagon, Portage Entry, and Eagle Harbor, and comparing them with samples off the tip of the Keweenaw.
Researchers also wish to surmise what happens to the current when it gets to the tip.
The Ranger III , a local icon and passenger vessel to Isle Royale National Park, will also help out. We will also be using optical measures to look at differences between terrestrial water, such as brownish Portage Lake, and Lake Superior, what we call lake water. The current is warmer than water that surrounds it, being formed by near-shore shallow water, which tends to be warmer due to solar heating. The thermal bar forms in the spring and becomes well-defined at some time. The thermal bar breaks up later in the summer when the surface of the lake heats up and differences in temperature take on a horizontal look across the lake.