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Grand Haven students participate in annual fishing event
Grand Haven Tribune (5/15)
In Michigan, Grand Haven Area Public Schools partnered with a nonprofit organization called Pursuing a Dream to give about 300 students with special needs the opportunity to fish and enjoy the outdoors.

NYPA funding aids three St. Lawrence River projects
Watertown Daily Times (5/10)
The St. Lawrence River Research and Education Fund has provided funding for three projects that support environmental education in and around the riverís ecosystem.

Lake Michigan Academy students learn from 'Salmon in School' project
MLive (5/9)
About 100 schools throughout Michigan are selected to take part in the Lake Michigan Academy program that aims to help stock local rivers and support fishing as a leisure activity.

Huron Perth students find Lake Huron threats
Blackburn News (5/1)
Nearly 60 high school students from the public and separate boards in Huron and Perth counties spent one day at the Oakwood Inn in Grand Bend, Ontario, where they were learning about the environmental threats and challenges to Lake Huron.

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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