September 16,  2008

ANNOUNCEMENTS

IF YOU MISSED CLASS TODAY

In class today we did the following:

1.  A few comments were also made about Test #1 on Thursday.   Some of the preceptors will hold a STUDY SESSION for Test #1 on Wed night (Sep 17) from 7:15 - 8:30 pm.  Where?  No room has been reserved, so meet in the ILC Courtyard at 7:15 and look for the preceptors and other NATS students. 

2. Dr H wrapped up Topic #6 on Radiation Laws, including a discussion on harmful UV radiation and the need for full-spectrum protection of UVA, UVB & UVC wavelengths of radiation.

Wrap-up of Topic #6 Radiation Laws   [color pdf]    [grayscale pdf]

3. Dr H then introduced Topic #7 on  Tree Rings &  Dendrochronology

   Topic  #7  Tree Rings & Dendrochronology  [color pdf]  [grayscale pdf]

A video was shown as part of the Topic #7 presentation -- a segment of The Desert Speaks PBS TV show on "Medieval Drought in the Southwest" (show #1611).  Here's a description:

Between roughly 900 and 1260 AD there was a massive drought that severely impacted the plants, animals and people of the Southwest. Now referred to as the Medieval Drought, the best records of this phenomenon can be found within the trees that lived through this difficult time period. Host David Yetman hikes with Tom Swetnam from the University of Arizona's Laboratory of Tree-Ring Research through the White Mountains of California and Sequoia National Park to observe how scientists use tree rings to gather evidence of climate conditions from thousands of years ago. By taking a core sample from the bristle cone pines of the White Mountains, scientists learned of this Medieval Drought and roughly how long it lasted. Some of the dead and downed sequoias in Sequoia National Park corroborate this information with evidence of the drought in their tree rings. This episode also offers an examination of the ruins of some of the people most affected by the drought, the Anasazi Indians, at Bandelier National Monument, a trek through a "ghost forest" and a first-hand look at "yoda" trees.

4.  The class ended with a little bit of time to begin looking at wood specimens and tree rings in the G-2 WOOD KIT Group Assignment which will be finished in class on Thursday after Test #1 is over.

ANNOUNCEMENTS

• Test #1 is on Thursday - “Top 10” is posted in D2L – There will be a Preceptor Study Session: Wed Sep 16  from 7:15 – 8:30 pm  -- no room yet, so meet in the ILC Courtyard at 7:15 to join up with the preceptors.
   
• Assignment I-1 Your Ecological Footprint is now graded and in your group folders – please take home your graded work. Grades for I-1 and G-1 will be posted in D2L soon.

IF YOU MISSED CLASS TODAY:   

• Review the Topic #6 wrap-up and Topic # 7 presentations above.
  
• You missed the interesting very "Medieval Drought in the Southwest" video.  Email Dr H if you would be like to borrow the DVD so you can watch it on your own.
  
• Review CLASS NOTES  pp 41-43 and 133-134 to get caught up on some of the information we covered on tree rings and to go over the background for the G-2 Wood Kit group assignment  that just got started at the end of class time.