Module VII...Earth's Changing Climate

Essential Question...How is Earth's climate connected to its geological, biological and cultural systems?

Explore:

A fun and interesting site for introducing the solar system, along with some of our neighboring extra solar system objects is found in a history channel interactive. Note that several of the elements most commonly found in the solar system are hydrogen, helium, carbon and nitrogen.

Stephen Hawking's Universe: An Answer to Everything

I like to use Stephen Hawking's Universe with my physics students...this you tube video is a great introduction to Hawking's views...Hawking is attempting to find the "theory of everything" by combining Relativity with Quantum Mechanics. It also includes some of Einstein's work.
This you tube video describes how our solar system came to be from just a cloud of gas and dust. Combine nebula dust and gas with supernovae remnants, along with gravity, then fusion at the center of the rotating "cloud" and a solar system is born.

Explain:

I find it interesting how the views differ from one source to another when it comes to the number of stars in a galaxy and to the number of galaxies in the universe. When obtaining my master's from the University of Colorado, the numbers used were approximately 400 billion for both. Another interesting piece of data they use is a comparison with the number of stars with the grains of sand on all of the beaches of the earth. Beach sands...10^18 and stars in the universe...10^22. These numbers are difficult for anyone to wrap their head around...beginning with me! "Universe Today" and "Extreme Space" has numbers that are similar to the ones mentioned above. Very cool statistics to use when introducing the vastness and huge numbers used as we discuss stars, galaxies and the universe!

From universe to atoms...quite a jump, but directly connected! Where and how is the matter that makes up the universe created...STARS...through the method of fusion. What is fusion? Fusion is the process that energizes stars. It is the reaction in which two atoms of hydrogen combine together, or fuse, to form an atom of helium. (Atoms besides hydrogen, fuse together in stars to make other atoms up to and including iron...atoms above iron on the chart are fused in supernovae explosions) In the process some of the mass of the hydrogen is converted into energy...up through and including iron on the periodic table. Above iron energy is absorbed so the process slows, resulting in a dying star. The easiest fusion reaction to make happen is combining deuterium (or “heavy hydrogen) with tritium (or “heavy-heavy hydrogen”) to make helium and a neutron. Deuterium is plentifully available in ordinary water.

Extend:

There is a great diversity of beliefs concerning the age of the Earth and the rest of the universe, with the age of elements being an integral part of that puzzle:

*Most estimates based on a literal interpretation of the Bible, and in particular the belief that the Book of Genesis refers to a 24 hour day, cluster around 6,000 years, 2,000 years for both the age of the Earth and of the rest of the universe. These dates of creation are based on various and diverse interpretations of the Bible.
*Belief in a "young Earth" continued among scientists, until the early 18th century, when it became obvious to most researchers that geological processes were exceedingly slow, and must have been accomplished over incredibly long periods of time. A 5,800 year old earth simply was not possible. A hundred years later, investigators studying Egyptian remnants found that the civilization of Egypt began earlier than the time assigned for the creation of man. Once limited from the time constraints imposed by the young Earth concept, progress in geology and other earth scientists advanced by leaps and bounds.
*Most estimates of the Earth's age, based on actual measurements and calculations, are clustered around 4.5 billion years. Scientists further believe that the earth's crust solidified about 3.9 billion years ago. Parts of the universe itself are much older, dating back to the big bang, some 15 billion years ago. Such estimates are accepted by most old Earth creationists, by essentially all geologists, biologists and other earth and life scientists.

Carbon...also known as the element of life is the next topic. I begin atomic structure of atoms by describing how "empty" they are. I describe this concept by taking a Hydrogen atom and enlarging it until the proton is the size of a dime...where would the electron be? Place the proton on the fifty yard line of the football field and the electron would go around the goal posts. 99.9999% nothing! I take my thumb and index finger and call it my neutron shooter and pose the question..."if I fire my neutron through my students, lined up back to back, what are the chances that the neutron would go through everybody without hitting a thing! I also state that there are as many atoms in one human breath as there are number of breaths in the atmosphere of the earth. I use these examples to try to give my students an idea of not only how small they are, but also to reinforce the concept that it takes many, to say the least, to create a tiny dot with a pencil on paper.

We then use the element Carbon to express the concept that atoms are only borrowed...we all have a few carbons in our bodies that were borrowed by Hitler, Einstein, George Washington and everyone else who came before us. The Carbon Cycle helps us to understand the that the atoms that make up our bodies are only on loan and then put directly back into the cycle, but also the fact that atoms do not age! They will remain what they are "forever", unless they go through another fusion or fission process. I also like to point out that the food we eat for Calories (energy) comes from something that was once alive...ALL life as we know it is carbon based! As Carl Sagan stated, "we are all made of star dust". We (humans, animals, plants, the earth itself, our sun, stars, etc.) are all connected directly to the rest of the universe...we are the result of previous star life and death!

Evaluate:

The Teacher's Domain descriptions of how the elements needed for life were/are created (carbon, nitrogen, oxygen, etc) and the rise of greenhouse gas levels in the atmosphere (especially carbon dioxide) following the industrial revolution and in particular in the last couple of decades, shows clearly that humans are givers and takers when it comes to the concept of "our place in the universe" and directly on our earth's atmosphere. The testimonies of native people as to how their subsistence culture is changing or has changed, not by choice but by necessity to maintain their style of life, as a result of global temperature increase should make us all realize that no matter where we live on this earth, if we choose to ignore or blame greenhouse gas increases on mother nature, we will all eventually be effected in one form or another. As was stated in a previous module...it really is a disgrace to mankind that those who contribute the least to greenhouse gases are effected the most by them!

Teacher's Domain is beginning to change the way I teach...more technology integration is not only a great asset from an informational perspective and lesson plan viewpoint, but I have found that students are more engaged when GOOD technology is built into my lessons...my low performing students seem to rise even more! Thank you TD!