Since we can’t use our projector I decided to put the powerpoint presentation on the web.

Anyway many of you were having some difficulty identifying the step in the rock cycle represented by each stage in your investigation.  The illustration of the rock cycle in the investigation packet should help and also, later in the investigation, you will complete an interactive web activity. Click on the picture below and work through the interactive rock cycle activity now. You should then be able to complete your investigation (here is a copy of the investigation) (Here is a guide to the write-up). If you want to improve your test score from class take the web test again; print it and give it to me in class.

Now enjoy the video!

Reflecting on what I have learned so far about plate tectonics leaves me with more questions than answers. Can you help me to answer the question below and better understand the effects of plate tectonics on the surface of the Earth? I learn best through pictures and short explanations so creating an informative poster would be great.

1) I heard something about the Atlantic Ocean getting larger; how is that possible? How fast is it growing? Can I see it?

2) I heard that the Atlantic Ocean is getting bigger, so it made me wonder do the continents get larger too? How could a continent grow?

3) I was looking at a map and there are lots of mountains all around the world. How do mountains form? Are any forming now? Do all mountains form the same way?

4) I saw a map that showed the location of volcanoes and I noticed there was a whole bunch of them around the edges of the Pacific Ocean. How do volcanoes form and why are there so many near the Pacific Ocean?
 
5) I heard that volcanoes form near the edges (boundaries) of tectonic plates. But I saw volcanoes in Hawaii and I know it’s not near the edge of a plate how did it form? Are there other volcanoes that aren’t near the edges of a plate?

6) We saw that earthquakes happen along plate boundaries but I don’t understand why. I also want to know how earthquakes can be used to find out about the inside of the Earth.

Click the image to read the article.

Speaking of El Nino projects, I’m still working on grading all of them; please be patient. I should have all the grades done by Monday. I look through them all first to get an idea of how well you did. Then I grade each one, after which I go back and take a final look before putting grades in Progress Book. Below is an outline of what I’m looking for.

Ocean circulation and how it changes during El Nino. 

• Factors that influence currents: winds, land masses, Coriolis effect
• Normal non-El Nino Pacific currents: strong easterly trade winds, easterly equatorial currents, mounding of warm surface waters in the western Pacific, cold deep water upwelling along South America
• El Nino changes: weak or reversed trade winds, equatorial currents reverse (flow down hill) towards east, central and eastern Pacific warm, western Pacific cools, upwelling ceases.

Relationship between ocean and atmospheric circulation during El Nino:

• Changes in pacific equatorial currents and warming of central and western Pacific affects atmosphereic (Walker Cell) circulation. Normal Walker Cell circulation collapses or reverses, trade winds become weak or blow from the west and warm moist air raises over the central and eastern Pacific causing rains in normally dry areas, low pressure moves east, high pressure takes over west.
• Jet streams move south across US increasing precipitation in the south and making northern US warmer
• Changes in these circulations affect the weather around the globe

Weather impacts in Central Florida:

• Changes to jet stream results in fewer hurricanes due to increase wind shear aloft, hurricanes that do form tend to be pushed more towards the north Atlantic.
• Temperatures do not vary significantly, some slight cooling in winter months of about 2-3°
• Increased cloud cover and rainfall, an additional 10 inches (30%). This may have some negative impacts on crops and tourism, however it helps to recharge the aquifers and reduce the number of brush fires
• Increased likelihood of tornadoes

Relationship between ocean circulation, the aquatic food chain and El Nino:

• During non El nino years upwelling occurs along the west coast of south America. This upwelling brings nutrient rich cold bottom waters to the surface where it helps feed small organisms called phytoplankton. Phytoplankton are producers and form the bottom rung of the ocean food chain.
• During El Nino years the upwelling stops which results in significantly less phytoplankton. The reduced levels of phytoplankton means each level higher up on the food chain will have insufficient food.

How El Nino changes might affect the food chain/production in Florida:

• While El Nino has a significant negative affect on the fishing industry along the west coast of South America, it does not have a significant impact on fishing in Florida. El Nino is an event in the Pacific ocean not the Atlantic. However it may affect imports of certain fish and fish products raising prices due to decreased catch
• El Nino does affect our winter crops in Florida with increased rainfall and reduced sun. Increased rain might delay planting or increase diseases. Different varieties may need to be planted or different planting techniques used. Increased rain may be beneficial to some crops. El Nino even affects cattle raised in Florida, as pasture area is less productive and excessive rain can lead to hoof problems.

Here’s an excerpt from Discovery News about today’s quake.

Sept. 29, 2009 — A powerful earthquake with a magnitude of up to 8.3 struck off the South Pacific island nation of Samoa on Tuesday, triggering a tsunami as coastal residents fled to higher ground.

The Pacific Tsunami Warning Center said waves 1.57 meters (five feet) tall hit American Samoa, while 0.7 meter waves were recorded in Samoa.

The center had earlier issued a tsunami warning for a large swathe of the South Pacific including Fiji, New Zealand and Tonga after the U.S. Geological Survey reported a 7.9 magnitude quake.

The center later said an 8.3 magnitude quake had been recorded at a depth of 33 kilometers (21 miles). It was not immediately clear if this was the same quake and the USGS’s website did not provide exact details of its location.

“Sea level readings indicate a tsunami was generated,” said a statement from the Pacific Tsunami Warning Center.

WATCH VIDEO: Learn more about the Pacific Coast’s tsunami warning system.

Related Content:

• Planet ‘Restlessness’ May Predict Big Quakes
• Triple Junction of Crusts Caused 2007 Quake
• HowStuffWorks.com: Earthquakes
• More Discovery News

Over 70% of the elctricity in the US is produced from fossil fuels. How much of our non-renewable energy resources do we have left? When will they begin to run out 2030, 2050 or will they last longer?

What should we do?

Rock Cycle (Copyright © 1999-2003, Wheeling Jesuit University/Center for Educational Technologies®. All rights reserved. Used with permission)

I like this illustration of the rock cycle showing how rocks change over time. Click on the picture or follow this link to read more.

Remember how we said that earthquake activity can signal a possible volcanic eruption? Well scientist have recently noticed an increase in seismic activity around Mt Reboubt in Alaska.

A little hard to read but here is an image from the seismograph. Click on the image to get a larger view.

I’m sure many of you do not know where Mt Redoubt is located so here’s a map. 

So I wonder. Do you?

What is the inside of the Earth made of? How hot does it get? I wonder…..