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Pair plans to walk around Lake Superior
Sault Ste. Marie Evening News (2/3)
While people have driven, biked, sailed and even kayaked around Lake Superior, there are only a few records of people walking around the lake. Two individuals are making plans to do just that.

EDITORIAL: Lessons from the wind: Students will capture data that could save district money
Muskegon Chronicle (1/14)
Wind power has become a hot button issue in West Michigan. Grand Valley State University researchers are studying the issue under a grant and will be reporting the results as each section of its study is completed.

Fishery Trust invests in future
Grand Traverse Herald (1/13)
The Great Lakes Stewardship Initiative has an ambitious goal: create the next generation of Great Lakes stewards whose advocacy will support the lakes' long-term sustainability. The Grand Traverse Conservation District will be an integral part of this effort.

TEACH Calendar of Events
What's going on in your neighborhood this month? Meet other people and learn together at recreational and educational events! Our new dynamic calendar is updated daily with current educational events.
TEACH Questions & Answers

Do the Great Lakes have tides?
from Jean in Milton, Massachusetts and Thor in Davisburg, Michigan

The same forces are at work on lakes as on oceans -- the moon pulls on inland lakes, too. However, you won't find large tides on lakes as you do on oceans; lakes just don't have enough water in them for large tides to occur.

Dr. David Hollander -- a specialist in lake systems at Northwestern University -- was asked about tides on inland lakes. He said that the Great Lakes sometimes experience slight changes in water levels over short time scales, and in spring, there's a substantial influx of water due to melting of winter snows farther north. Yet, none these changes in water level can be called a true tide.

Click to see larger image. However, there is some disagreement on the subject. According to the Canadian Hydrologic/Hydrographic Service, the Great Lakes experience tides from 1 to 4 cm, the strongest being on Lakes Superior and Erie. These tides are often masked out by meteorologically induced phenomena, such as a seiche (pronounced "sayshe"). When wind pushes down on one part of a lake, the water surface rises in another part, producing waves (most noticeable on Lake Erie because the lake is so shallow).

Read TEACH's segment, Great Lakes water levels, for more information; if you'd like a more in depth explanation, download the Great Lakes Commission's Living with the Lakes brochure.

Thank you both for your question!


Answered on October 1, 2000

 

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