Friday, November 30, 2012

What causes jet streams?

Jet streams are one of the most interesting phenomena that people never see, never experience, and probably don't understand. Yet, seldom does a TV meteorologist make it through a broadcast without mentioning them. So, what's all the fuss about? What causes them? How do we know where they are? I've tried to find answers to these questions AND figure out ways to make jet streams interesting to my students. This week's resource is a PowerPoint presentation that I put together based on what I learned. CLICK HERE to check it out. For best results, download the presentation to view it.

The key that helped me understand why there are jet streams was a "pressure block" activity that I did while taking the DataStreme (online) Course offered by the American Meteorological Society. Although I don't have students do the activity, I use photos of the blocks in my presentation. The topics covered in the PowerPoint are . . .

1. Jet Streams: What and where?

2. How do we know where they are?

3. Why are they important?

4. What causes them?

NOTE: The presentation is posted on www.slideboom.com - a free site that allows you to post up to 100 presentations, which students or colleagues can view or download. To view other presentations that I've posted type "rod benson" into the search box.

Thursday, November 22, 2012

Concretions: An Interesting Stop on the Rock Cycle

Three friends and I recently took at kayak trip through the White Cliffs of the Missouri River in north-central Montana. We took time to do some short hikes to explore the fascinating geology of the area. During one excursion we hiked into the Eagle Creek drainage where concretions are especially abundant. Telling students about "concretions" is a great way to make the "compaction and cementation" (lithification) part of the rock cycle more interesting. Before you explain how they are formed, consider showing students photos of concretions* and then ask them to come up with a theory. To learn more about concretions CLICK HERE. Similar processes were also involved in the formation of the strange pedestal rocks, which we saw several miles downriver. To see 45 photos from our trip, CLICK HERE.

NOTE: If students have a good understanding of "plate tectonics" and "the rock cycle", they have a decent foundation in geology. For more about the rock cycle, check out this Rock Cycle PenCast.

*The links embedded in the above text will take you to several photos.

Friday, November 16, 2012

Quality Online Courses for Earth Science Teachers

Some of the best courses that I've taken over the years have been those provided by the American Meteorological Society. The AMS offers online courses related to meteorology, oceans, water systems, and climate. They are free, and you earn 3 graduate level semester credits! More importantly, the courses are top-notch, but not overwhelming. I've taken all of them except for the climate course, and they have all impacted my instruction in a positive way. I highly recommend them. CLICK HERE to learn more about the meteorology course or HERE to learn more about the other courses.

This week on PBS: The Dust Bowl by Ken Burns airs on PBS Sunday and Monday evening, Nov. 18-19 at 8 pm Eastern Time. Also, the topic of this week's NOVA is about superstorm Sandy.

Friday, November 9, 2012

The Role of the Moon on D-Day

In honor of Veterans Day (Nov. 11) take a look at how the Moon played a major role in the planning of one of the most important invasions ever; the invasion of the northern coast of France on June 6, 1944. CLICK HERE to find out more.

Friday, November 2, 2012

Image Lets You See Vapor in the Air

One of the best things about the internet is the access that it gives to real-time weather images. This allows me to show students many different aspects of a storm as it moves through. As much as I enjoy geology topics, it seems that students have a hard time getting excited about changes that take place over thousands or millions of years. On the other hand, weather changes from hour to hour, minute to minute. We can compare what we see happening outside to satellite images, weather maps, RADAR images, pressure maps, temperature maps, current wind animations, etc. Its relevant and it makes sense!

One of the fun new images I learned about on Mike Heard's Blog shows "Total Precipitable Water" (vapor in the air over ocean water). Mike is a broadcast meteorologist in Butte, Montana. He explains the images on his blog site. To see the current loop, CLICK HERE. . . Or, CLICK HERE to watch a YouTube video about the images.