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Ice-Out Update: March 6, 1998

Today's Report Includes:

Walden Pond Announces Early Ice-Out!

Official 1998 Ice-out Date
February 26th @ 1 pm

"Four days later than last year--and nearly a month earlier than any of Thoreau's recorded dates," exclaimed Susan Wheelright, of Fayerweather School. "Another mild winter in New England!"

So ends our 1998 Internet Ice-Out contest for Walden Pond, a full month earlier than the deadline! If you live in the Eastern United States and you think it's been a warm year, now you have solid facts to prove it. We've included Thoreau's ice-out records from the 1800's in the chart below and added records for the 1900's, collected by Journey North students. This has been an unusually warm year!

Ice-Out Records for Walden Pond

Collected in the 1800's by Henrry David Thoreau
1845 April 1
1846 March 25
1847 April 8
1851 March 28
1853 March 23
1854 April 7
...... and in the 1900's by Journey North students
1995 March 18
1996 March 23
1997 February 22
1998 February 26

Introducing This Week's Official Ice-Out Observation Post

Our 3rd official ice-out post is Lake Minnetonka. This still-frozen lake is located right outside the window of the Journey North headquarters in Minnesota. People here have always been eager for spring, and for the past 111 years they've kept ice-out records for this lake. By law, all ice fishing houses must be removed by March 1st, because heavy trucks are needed for the task.

Ice-out dates are one of the best natural ways to measure the amount of heat the earth has received, and compare spring's pace from year to year. Look at the 111 years of ice-out data , and then see how you would answer these questions:

Challenge Question #4
"When do you predict ice-out of Lake Minnetonka will occur in Spring, 1998? Do you see a correlation between el Nino years and early ice-out dates? Is the earth warming? Do the 111 years of ice-out data from Lake Minnetonka support the global warming theory?"

Ice-Out Data from Journey North Observers

"The only bodies of water that freeze are the dogs' water bowls!" wrote Mrs. Veselka of Houston, Texas. "The students do remember that their swimming pools froze on top a long time ago (estimate: 1988)." (dveselk@tenet.edu)

 Report the Ice-Out Date of Your Local Waters
Thanks to everyone for contributing ice-out data, especially those in the south where this concept is so foreign. Remember: When ice-out occurs on your local lake, pond, river or ocean, please report to Journey North.

How to Respond to Today's Challenge Question

1. Address an e-mail message to: jn-challenge-ice@learner.org

2. In the Subject Line of your message write:
Challenge Question # 4

3. In the body of each message, answer the question above.

The Next Ice-Out Update will Be Posted on March 20, 1998.