Saturday, December 18, 2010

Module IX Tales of Drunken Trees, Methane Bombs & Glacier Blues


 The Learning
Viewing the TD videos allowed me to gather valuable information on the module’s topic this week.  I found them to be full of great photography and content for students to see first hand. 

The pictures of “drunken trees” and the stories of lakes disappearing around Huslia was quite an eye opener.  I found it a little ironic of the talk about decreasing the use of fossil fuels to help combat this problem but in the next scene, kids and adults are cruising around the village on snow machines or four wheelers.  You can’t take the outboard off the boat if you are going up river?!
The thawing of ice-rich permafrost causes subsidence of the land surface, creating thermokarst ponds and causing trees to tilt, which is shown in this peatland terrain in Churchill, Manitoba.  Photo by USGS

This changing arctic landscape  increases the threat of fire and new species of trees are showing up that have never been seen before.  That’s scary.

Permafrost is any rock or soil that has remained under 32˚ degrees F for over 2 years.  The Bank Island video showed many images of thawing permafrost. They estimate by 2100, the permafrost will be thawed to 11 feet. Ouch!

The interactive Mountain of Ice video showed sea levels 20000 years ago that were 400 feet lower than today.  What ancient villages are off the coast of the United States?  Submersibles should be scouring the bottom for more clues!

The rest of the videos showed great black and white photos taken hundreds of years ago and compared them to recent photos taken in 2004.  What I found so interesting was the amount of contrast and quality those old photos still possess.  I would rather look at those old photos than the washed out digital we have today.

Since 1850, the world’s glaciers have lost 30% of their total surface area.  That’s a lot of melting. 

So the fact that the world’s temperature has risen 1 degree F the past 100 years is starting to become a big deal. 

The Doing
 
Glacier study here in Southcentral would be a great way to introduce glaciers and global warming to a group of Anchorage area students.  Isostatic rebound were their school lies in the Anchorage bowl was over 1000 feet.  Imagine that. 

So much of the topography around the Anchorage Bowl and surrounding mountains is due to glaciers.  Carving turns in the Glacier Bowl above chair 6 at Alyeska wouldn’t be possible without the cirque carved by a glacier.

Portage Glacier still provides clues on the movement of these giant masses of ice.  Here are photos of scratches left by the mass of rock and ice as the glacier moved through the Portage valley.
Portage Glacier 2007. photo by author

Scratches in nearby rocks made by glacier.  Photo by author

The best site on our module would have to be the extreme Ice survey.  The time elapse photography was amazing.  Any teacher working with curriculum that deals with erosion and glaciers should use this site.   Way cool.

Another was the methane bombs being lit by the teachers and students of UAF.  I saw this in Portage one winter and can’t wait to find some pockets of CH4 around my house to light (to the chagrin of my wife….”you are NOT bringing the kids!).

This module got me thinking on how I could explore this in the classroom.  How about finding Permafrost on other planets!  Of course NASA is already exploring that with the Phoenix.
There are also UAF resources for exploring permafrost right here in Alaska.  Google Earth and Permafrost make a great connection.

What really interested me was the isostatic rebound of the land around Anchorage.  The topography around here is a natural field trip right out the door.
From this map, you can see the various landmasses and features made by glaciers. Source http://www.alaskageography.com/essays/glaciers.htm

I have heard of rebounds in the thousands of feet but could only verify under 300 feet.  But just imagine how much rock and ice must have been on the flats to lower it even that much.

The Shameless Plug

http://www.williwaw.com/magento/index.php/weather-calendars-and-publications.html
I can't leave this weeks blog without a mention about the nice folks in Haines that put out the Alaska Weather Calendar.  I have been giving and receiving these wonderful calenders since late '95 and I can't tell you enough about how much Alaskan weather photos and facts they stuff in there.  Check out their site and check up on the winter forecast and other goodies they have.
 Stay safe and have a very cheerful Christmas Solstice.  If you are in the Indian Valley look for the bonfire to the North.  The pagans will be celebrating the longer days to come at December 21st at 2:38 pm. 

Also look for the lunar eclipse that will happen late Monday night!

The Other Voices

First stop was the wonderful site from Marilyn that turned me on to Antonio Stradivari's violin making and the wood used during Europe's little ice age.  Wow

Next I went a blogging to Bobbi-Ann's site and wondered how she could work with those fish swimming all around her page?  Thats pretty cool.

Dave's site is pleasing to the eye.  The photos in the background make it look so professional.  I also agree that the climate data out there can be interpreted so many ways and  we need to keep an open mind about the data and solutions to the problem.



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