Saturday, November 27, 2010

Module VIII - Cryosphere Introduction

Explain - What new learning have I taken from this module?

 It is easy to forget that the melting of sea ice doesn't actually change the level of the oceans.   This module was a great reminder of this and the associated experiment with the ice melting in the glass of water is a very good demonstration of that phenomenon.  This module pointed out that the bigger issue with melting sea ice is the fact that the albedo of ice and snow is much higher than that of open water.  Yet another one of those nasty positive feedback loops. 

The second page of the module pointed out some of the other effects of the melting sea ice.  Shishmaref is a coastal village bombarded by my more violent winter storms with much less ice to keep the waters down, resulting in alarming erosion of their little island.  Whalers in Barrow and hunters in Northern Canada have to adapt to much more difficult and dangerous conditions to get to their food.  Read more about that in Charles Wohlforth's The Whale and The Supercomputer.  If humans with their snow machines and motor boats are having a harder time of it as the sea ice vanishes, imagine the plight of the polar bear.

all photos:  D. Armstrong

Extend and Evaluate - How can I use this week's resources and how useful, insightful or relevant are this module's information resources to me?

I found the Our World 2.0 website to be an incredibly diverse source of articles on climate change and indigenous peoples around the world.  It would be a great place to send students doing research on those subjects.

I felt that the video on Shishmaref would be a great way to bring home to the students how global warming is already effecting people within their own state.  Climate change is not some distant phenomenon that effects only the people of New Orleans or some tropical atoll.

The NASA video on the Earth's cryosphere will be very instructional when introducing the cryosphere to students.  It is a great overview and does a great job of showing how changes in everything from Rocky Mountain snowpack to Greenlandic glaciers has an effect on the planet.

Lastly, of course, I can use the experiment with the melting glass of ice and water to demonstrate everything from melting sea ice to buoyancy and density.  The salt water experiment is also a good one.  Our physics classes already do a lab in which ice cream is made the old-fashioned way.

Three Colleagues

Dan's blog has a great link to Ian Guch's website with all sorts of free stuff for teaching chemistry.  Great site, Dan.

Janet's blog has a link to a very moving video of one man's personal experience with climate change.

Tyler's blog has a great shot of Mt. Redoubt erupting, a reference to Project Wild's excellent resources and a useful link to UAF's science forum website.

Sunday, November 21, 2010

Module VII - Changing Climate Introduction

Sample of coquina
Explain - What new learning have I taken from this module?

This module was a great reminder about the eons of natural carbon sequestration that has been taking place since the dawn of life on this planet.  I was amazed to learn how much life has changed the atmosphere and how life and the atmosphere have evolved in unison.  In light of how much carbon has been sequestered, this makes a lot of sense, though it's not obvious without being pointed out.

When discussing climate change, I have often pointed out that when you burn the wood of a tree, you are re-releasing the carbon into the atmsophere that that tree has been removing for the last hundred years, or so.  Likewise, when you burn oil, you are now going back millions of years and releasing the carbon that was sequestered, then.  I had heard about carbon sequestration in the form of calcium carbonate in the shells of animals, but hadn't really thought about what a vast cache of carbon this represents.  It is a bit depressing to think about the increased acidification of the oceans making it harder for organisms to precipitate calcium carbonate from the water.  Yet another positive feedback loop.

The video about Inuit observations of climate change reminded me of discussions with villagers, a few years ago, about how the winters along the lower Kuskokwim just weren't as severe as they were 20 years earlier.  One of my last years in Tuluksak, the mercury dropped below freezing in early October and didn't get above freezing until late March.  All of the older villagers said that was how winter was supposed to be.  It was the only such winter that I experienced, there, in five years.

Extend and Evaluate - How can I use this week's resources and how useful, insightful or relevant are this module's information resources to me?

Helix Nebula
The video The Elements - Forged in Stars brought me back to my Freshman Astronomy class in college.  I will use this in both my Earth Science class and my Physical Science classes.

I will also use the video Ingredients for Life - Carbon in my Physical Science classes when we touch on organic compounds and why such a vast variety of carbon-based compounds exist.

The video Global Warming:  Carbon Dioxide and The Greenhouse Effect shows a great demonstration of how effective carbon dioxide is when it comes to absorbing heat energy.  It's a great visual when the infrared image of the scientist's face disappears behind a chamber of carbon dioxide.

The Capturing Carbon clip will be a great motivator when it's time to put on a science fair.  How great is it that the scientist was able to put his daughter's project into actual use?

Three colleagues and three comments

- I agreed with Alison's comment about how amazing it is that the lowly parrot fish can create all that sand in the coral reefs.  It'll give me pause the next time I curl my toes into the coral sands of Hawaii.

- I enjoyed Kathy's photos on last week's blog.

- Marilyn's blog reminded me how powerful the images on the Information is Beautiful website are.  She also mentioned a song by Tom Lehrer that I, too, play for my classes when we study the elements.

Saturday, November 13, 2010

Module VI - The View from Space

Explain - What new learning have I taken from this week's module?

I found the information on toxins and haze accumulating at the polar regions rather sobering.  Ever since moving to the Kenai Peninsula, I have noticed what seems to be an inordinate amount of cancer cases amongst the local population.  This observation is completely unscientific, but it does make me wonder whether it's an effect of the local refineries or of toxic accumulation in the arctic regions.  If this does have anything to do with regional accumulations, then this is potentially devastating for Native people who live farther north and get a higher percentage of their calories from locally hunted and gathered food.  Compare the age-adjusted cancer death rate on the North Slope to that of the entire state of Alaska at this Census website.  Is there a connection?

The Native pilots video took me back to living in Bush Alaska and needing to fly to cross-country meets at neighboring villages and the general flying conditions in the state.  I have immense respect for Bush pilots and am fascinated by Alaskan aviation history.  Check out the book "Wager With the Wind" for one pilot's exciting biography.

I was amazed by the amount of information that can be gleaned from the silent video of global water vapor circulation over the period of a year.  Watching the slow, westward flow of equatorial moisture pile up against the Andes during the (northern) winter months made the cause of the Amazon's wet and dry seasons crystal clear.  Likewise, when things piled up against the Himalayas in the late spring and summer, the cause of Asia Minor's monsoon season suddenly made sense.

Extend and Evaluate - How can I use this week's resources and how useful, insightful or relevant are this module's information resources to me?
Cyclonic cloud formation off east end of Cuba

Again, I enjoyed the Google Earth exercise and liked the weather overlay.  When I get to weather with my Earth Science class, I will definitely be incorporating this into my lesson plans.  I'll also be using the TD interactive resources for atmospheric structure and the anatomy of warm and cold fronts.

I will also use the You Tube video "Making Ice by Boiling Water" when talking about the energy of phase changes with my Physical Science classes and Earth Science classes.  Of course, the danger of watching You Tube is getting side-tracked on unrelated themes - I spent half an hour checking out videos on superfluids.

Three colleagues and comments

Janet's blog has a great link to the Skeptical Science website and she pointed out that you can find webcam shots from within the Google Earth screen capture.

Dan's blog had some great information to get even more use out of your TD file by adding external links.

Kevin's Blog pointed out the close correlation of pollutants in Greenlandic ice cores and the changing activities of mankind.

Saturday, November 6, 2010

Module V - Ocean Systems

Explain - What new learning have I taken from this module?

Extra bouyant in the
Dead Sea
I found this module to be a fascinating one.  Ever since I was a kid I've been astounded by the superlatives of the ocean:  the 40,000-mile mountain chain, the depths able to swallow Mt. Everest, the worlds tallest mountain, the draw of over half of humanity to it shores - the list goes on and on.  As an adult, I became familiar with the significance of density diffences and temperature differences in the oceans through education, scuba diving and travel.  This module was a great synopsis of the factors effecting ocean currents,  world weather, resources and, ultimately, human societies.  I found the 1000- to 1600-year journey of a water molecule through the depths of the ocean to be fascinating.  Ever since doing some Cenote diving in the crystal-clear, fresh water of the Yucatan Peninsula's limestone caves, the halocline has fascinated me.  There, you can actually see the interface between fresh water and the salt water below.  It looks like a layer of clouds through which you can't see clearly from either below or above.  Check out this Youtube video of some divers going through a distinct halocline.  Every diver who has been in both fresh and salt water is familiar with the fact that you need more weights to compensate for your bouyancy in denser salt water than in fresh water and divers in the Dead Sea must need even more.

Extend and Evaluate - How can I use this week's resources and how useful, insightful or relevant are this module's information resources to me?

San Francisco at 37 degrees
46 minutes North
The most useful resource that I found in this module was the last half of the video about Ben Franklin's discovery of the Gulf Stream.  I found the animation of not just the warm surface current, but also the cool water dropping to the sea floor and returning to the Tropics to be a very good illustration of a fairly complex idea.  I would love to see such an animation that follows the entire 1000-year journey of a water molecule, but have been unable to do so, as yet.  I liked the demonstration with the lighter under the balloon.  It reminded of a trick I learned in Boy Scouts in which you can boil an egg in a paper cup over a campfire.  The paper burns away above the waterline, but stays intact where it's in contact with the water.  The exercise in GoogleEarth was also instructive, though I was unable to get the ocean temperature overlay to work.  I did, however, find a NASA image that shows the  difference between ocean surface temperatures on the two coasts of the U.S.  The cooler west coast waters certainly explain the cool, foggy summers of San Francisco, though the reason for Washington D.C.'s harsher winters is not as clear.
Washington D.C. at 38 degrees
53 minutes North
NASA image of ocean surface


Blue, glacial meltwater staying atop salt water
at the Columbia and Valdez glaciers

 I also thought that the experiment with melting blue-colored ice in warm, red water, would be very demonstrative in showing the difference in density of cool and warm waters.  Finding evidence on GoogleEarth of a similar phenomenon would be very instructive for students, though I was disappointed to find no evidence of this at the mouth of the Amazon River.  This, despite that fact that sailors of previous centuries were able to encounter less-dense fresh water atop ocean water days before arriving at the mouth of said river.

 Three collegues and three comments

I enjoyed the link on Tyler's blog to the beachcomber's alert site that showed how you can learn about ocean gyres by beach combing.

Amy's blog pointed out how incredible it is that Ben Franklin was able to map the Gulf Stream so accurately without the use of GPS or modern scientific equipment.

Janet's blog had a great link to the Oceans Alive website with a map in which Pangea is reunited - a great visual to show how much of the planet is covered by oceans.