The “health” of the Earth can be characterized by temperature as well as the pH of the oceans. We humans live and breath in a thin layer of gas called the troposphere.  This thin layer of atmosphere surrounding the Earth has always been in a state of change. Presently, the air that we breathe is 78% nitrogen, 21% oxygen, 0.93% argon and 0.0383% carbon dioxide plus a number of other trace gases especially water vapor.  The concentration of carbon dioxide is ~ 383 parts per million by volume.  Of great concern is the documented fact that the concentration of CO₂ has been rising and aside from seasonal variations this increase is well correlated with the introduction of man made sources of CO₂ (burning of coal, combustion, etc.).  The temperature of the Earth is established by a delicate balance between heat from the Earth’s crust (radioactivity), radiation from the Sun and re-radiation from the Earth’s surface to the surrounding Universe.  Clouds and aerosols also play a major role in this radiation balance.  Water vapor, carbon dioxide and other infrared absorbing gases in the atmosphere trap some of the heat being re-radiated out into space. The analogy to a Greenhouse has given the name Greenhouse Gases to these trace species. There is gathering data to suggest that the Earth is warming on average and this Global Warming has been attributed in part by some scientists to an increase in Greenhouse Gases.  The Earth acts much like the human body; a “fever” of a few degrees can cause alarm.  Many fear that the Earth may soon experience a “heat stroke”.  This talk will attempt to discuss some of the science in the debate over Global Warming.  In so doing I will also take note of the changing pH of the oceans due to increasing atmospheric CO₂.  

      A large part of the discussion on atmospheric composition and radiative energy balance (i.e., Earth’s temperature) will be based upon experiments at the University of Tennessee.  We have been carrying out atmospheric infrared absorption spectroscopy measurements using the Sun as the IR light source.  Tracking the IR absorption as the Sun rises over the Smoky Mountains and sets in the west over the Bull Run and Kingston Steam Plants we can study the distributions of gases over East Tennessee. 

• Create our T H R E E  H U N D R E D  F I F T Y ! banner
• Take photos for 350.org
• Coordinate in our Action Teams

• Discussion of Readings
• Introduction to Exonential models
• Submit an additional Action Plan Update P4
  (What is to be submitted is identical to P2, but please name the file yourteamname-P4 and submit to Moodle before the end of class today.)

• Work in groups on the Midterm Homework, M5 (due Tuesday)
• Submit an additional Action Plan Update P3
  (What is to be submitted is identical to P2, but please name the file yourteamname-P3 and submit to Moodle before the end of class today.)

• Submit an Action Plan Update P2

• Complete Modeling Assignment M4 individually for submission.
• Read pages 141-153 (all of Part 4) in the of the Dire Predictions text. We will have a reading quiz on this material on Thursday.

• Complete Modeling Assignment M3 individually for submission.
• Read pages 107-139 (all of Part 3) in the of the Dire Predictions text. We will have a reading quiz on this material on Thursday.

• Read pages 4-6 of the Environmental Issues text.
• Complete Modeling Assignment M2 individually for submission.

• Read pages 77-105 (all of Part 2) in the of the Dire Predictions text. 
• Read the entire CELTs Service-Learning Handbook which you received in class
• We will have a reading quiz on this material on Thursday.

• Join a team based upon the October 24th Ideas and submit an Action Plan P1

• Read pages 1-3 of the Environmental Issues text.
• Read pages 42-75 (the rest of Part 1) in the of the Dire Predictions text. 
• We will have a reading quiz on this material on Tuesday.
• Complete Modeling Assignment M1 individually for submission.

• Read the short "To the student" section in the Environmental Issues text. Then read the first 41 pages of the Dire Predictions text.  We will have a reading quiz on this material on Tuesday.
• We will also start working with the Environmental Issues text on Tuesday, so please bring it to class with you.

• Complete R2: On the KEF. Save this file as yourusername-2 and submit it before the beginning of our next class.

• Complete R1: Urgent Environmental Problems. Save this file as yourusername-R1.  We will learn to submit it at the beginning of our next class.