Submitted by Anonymous on Fri, 12/12/2008 - 20:31
Forums
Ancient Buried Ice in Antarctica

Hi Jackie, Barney Peterson here.  The kids in my fourth grade and I have read your journal entries and looked at your wonderful photos with great interest.  A question from the class is, if Antarctica is so dry, how is the ice cement formed?  What is it exactly? 

Keep up the good work.  We will continue to follow your adventure.

Sat, 12/13/2008 - 17:15

Jacquelyn Hams

Hi Barney,
It is good to hear from you and I am glad you are following the trip.

The question is outstanding, and one currently being addressed by many researchers in the Dry Valleys.  The question is, if Antarctica is so dry, how is ice cement formed?  Although the full answer is unknown, the following represents a best guess.
 
Even though air temperatures are constantly below freezing in the Dry Valleys, and snow fall is minimal, there are times when the sun warms surface rocks and allows some snow melt to form.  The snow melt percolates down into the soil and freezes, forming ice cement.  Given the extremely cold temperatures, the ice cement is stable for very long periods, and is being recharged by infrequent snowmelt during particularly sunny years.
You might want to look at the questions from Lollile's 6th grade Redd School class regarding the formation of cemented ice as well.
 
Jacquelyn Hams
Los Angeles Valley College 

Fri, 12/19/2008 - 07:40

Barney

Thanks for a very well-written and easy to understand reply. Our current science unit is "changes of state" and students are developing a pretty good understanding of freezing and thawing as our area is fast in the grip of a series of storms from the Arctic. Merry Christmas to you and stay safe and "warm" (relative term?).

Sat, 12/20/2008 - 20:38

Barney Peterson

Barney Peterson
Keep up the good work. Your responses to the many questions students are asking are really well done. We have tried some activities with simulated ice and sediment cores in class to give the students a taste of what the researchers do, but we can't duplicate the extreme cold that makes it possible to examine things before they melt. (Of course, if we were in school just now it would be very possible as we are in the grips of rare winter storm and when I checked my portable classroom yesterday it was 15 F outside and 42F inside. We would not have to work so fast just now.)
I will continue to follow your adventures through the holiday break and share them with my students when they return. Happy Holidays and be safe.
Barney

Sun, 12/21/2008 - 16:36

Jacquelyn Hams

Hi Barney,
Thank you and please continue to follow.  I am just back in Los Angeles (talk about culture shock!)  and I have a couple of journals to post with maps as soon as I adjust to being back and spend some quality time with the family. I do plan to follow up with Dr. Marchant's results and develop some lesson plans based on the trip.
Jacquelyn Hams
Los Angeles Valley College