This is a text version of the notes presented in class.

Feel free to email the instructor (dpalmer@kent.edu) with any
comments about the format and ease of use of these online notes.

1.Lecture 27:  Oceans and the Future
Focus Question:  How could a warmer ocean and a warmer atmosphere impact society?
Note:  Review for Final exam today-bring your questions-any questions from any material throughout the semester will be welcomed.
I will bring the old exams again-I plan to have them available before and after class today.
 

2. The Fossil Fuel Connection
Burning fossil fuels produces CO2 and water and releases heat
Example: burning 1 gallon of gasoline produce 19.6 lbs of CO2
 The impact of a population on atmospheric CO2 depends on:
  - size of population
  - affluence per capita
  - impact of affluence (i.e., technologies used)
Current CO2 emissions*:
 North America:  ~5 metric tons carbon per person per year
 Western Europe ~2 metric tons carbon per person per year
 Africa        ~0.3 metric tons carbon per person per year
*Data source: Carbon Dioxide Information Analysis Center, USDOE

3. Atmospheric CO2, 1950-1990's
Atmospheric CO2 can be measured directly from air samples
Measurements at Mauna Loa, Hawaii show an increase in atmospheric CO2 of 85 parts per million
(ppm) over the past 50 years
Data source: Keeling, D.C., and T.P. Whorf, 1998: Atmospheric CO2 records from sites in the SIO air
sampling network.  In "Trends: A Compendium of Data on Global Change", Carbon Dioxide Information Analysis
Center, US Dept. of Energy.

4. Atmospheric CO2, 1740-1990's
Air bubbles within polar and glacial ice are analyzed to determine CO2 levels in the past (yellow squares)
Atmospheric CO2 increased nearly exponentially from 280 ppm in the 1740's to about 370 ppm today
Other greenhouse gases have also increased

5. Just How Unusual is the Present Level of CO2?
Data shows that today's CO2 levels were last reached  125,000 years ago
Some climatologists believe that a doubling of today's  CO2 level last occurred 20-40 million years ago

6. Industrialization in the Greenhouse
Global temperature trends show a 0.6 deg C increase over the past 100 years and about 0.5 deg C increase
over the past 25 years
This is coincident with increases in atmospheric greenhouse gas concentrations
Graphics: (top) Average global temperature, 1860-1990's, (bottom) CO2 emissions.  Graphics courtesy of
US Global Change Research Information Office.  See   http://prod.gcrio.org/ipcc/qa/cover.html

7. Trends in Measured Surface Air
Temperature (Past 50 Years)
Red = warming trend
Blue = cooling trend
Larger circles = more warming or more cooling
Graphic: Courtesy of NOAA Global Historical Climate Network.

8. An Emerging International Consensus
"We conclude that the variations and trends of the examined indicators consistently and very strongly
support an increasing global surface temperature over at least the last century, although substantial
shorter-term global and regional deviations from this warming trend are very likely to have occurred."
- Intergovernmental Panel on Climate Change, "Climate Change 2001: The Scientific Basis"

9. Potential Climate Changes
Primary effects:
- Warmer temperatures
- Sea level rise
- Water cycle impacted
   (reduction in N.hemisphere snow)
- Sea ice extent reduced (Arctic)
- Changes in frequency/intensity of storms (particularly hurricanes)
Types of changes:
- changes in average conditions
- changes in variability
- rapid changes
- "surprises"
Graphic: Hurricane Floyd, Sept. 14, 1999. Courtesy of NASA.

10. Potential Impacts of Climate Change on Society
Many sectors of society may be affected...
- Agriculture and fisheries
- Infrastructure
- Water resource management
- Human health
- Ecosystems/biodiversity
Climatologists, economists, sociologists politicians and others are studying the potential impacts of
climate change on these sectors and on individual countries
Graphic: (top) Sunrise, courtesy of NOAA, (bottom) wheat harvest, at ARS Central Great Plains
Research Station, Akron, Colorado.  Photo by S.Bauer, courtesy of US Dept. of Agriculture.

11. Predicting Future Climate
Uncertainties:
- Interactions between different elements of the climate system (e.g., global warming and clouds)
- Future CO2 emissions are unknown
- Potential impacts of mitigation technologies
- Unforeseen surprises
Graphic: Climate change feedbacks, courtesy of United Nations Environmental Program, World
Meteorology Office.

12. What Does the Future Hold?
Options being studied include:
- Mitigation to reduce emissions
 - using fewer fossil fuels
 - energy efficiency
 - substitution of technologies
 - removing CO2 once it's
      produced ("sequestration")
- Adapation to a new climate
Graphics: (top) Site of a "clean coal" plant of the future, Brilliant, Ohio, courtesy of US DOE, (bottom)
  Cool change logo, courtesy of US EPA.

Time for a Review!  Remember, the FINAL EXAM is
Thursday May 3rd  from 7:45-10:00 AM in our classroom!

Covering the entire course, with special emphasis on the section after Exam 3
Style:  Multiple Choice & Matching
Number of Questions:  Between 65 and 75
 Approximately 95% from lecture material
 Approximately 5% from readings not covered in lecture

How much does this count?  It will count towards 40% of your final grade.
You will need to turn in both your scantron answer sheet AND your test to get credit on the exam.
BRING A PENCIL AND AN ERASER!