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Bay City tall ship sets sail for season of education, fun
The Associated Press (4/24)
An educational tall ship is back for another season on the Lake Huron waters off Bay City, Mich.

Salmon raised in Guelph classroom soon to swim in Lake Huron
Guelph Mercury (4/22)
Schools in Ontario are participating in the Lake Huron Fishing Club's salmon hatchery program, which aims to rejuvenate a salmon population that has been severely diminished.

Apostle Islands celebrates century of National Park Service
Superior Telegram (4/10)
In Wisconsin, Apostle Islands National Lakeshore joins parks, programs and partners across the country to encourage everyone to find their park and share their stories online at FindYourPark.com.

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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