1. Carbon Footprint of the U.S. Population: Causes and Spatial-Temporal Pattern Class Project Me/ENV 449, 4/30/2007 By: Louis Hsu Instructor: R. Husar Transportation Sector Carbon Emissions & The Carbon Emissions Factor

2. Overview of U.S. Transportation Sector Carbon Emissions 1.Categorization of the U.S. transportation sector 2.Causality chain model of carbon emissions 3.Graphs of historical transportation carbon emissions from 1960-2004 4.Graphs of projected transportation carbon emissions trends out to 2050 5.Parameters influencing the carbon emissions factor 6.Suggestions to improve the carbon emissions factor

3. Categorization of the U.S. Transportation Sector by Transportation Mode Passenger Transportation –Passenger Car –Light Truck –Bus Urban, Intercity, and School –Rail Commuter, Heavy, Light, and Intercity/Amtrak –Air Carrier Freight Transportation –Single-Unit Truck –Combination Truck –Class I Rail –Air Carrier –Water Domestic and Foreign vessels in US Waters –Oil –Gas

4. Causality Chain Model of Transportation Carbon Emissions With the following data, the U.S. population was directly translated into carbon emissions –Population (P) –Registered Vehicles (VR) –Vehicle Miles Traveled (VMT) –Passenger Miles Traveled (PMT) –Freight Ton-Miles (FTM) –Energy Intensity, or Fuel/VMT (EI)

5. Causality Chain Model of Transportation Carbon Emissions Passenger Transportation Model: –(P) x (PMT/P) x (VMT/PMT) x (Fuel/VMT) x (Carbon/Fuel) = Carbon Emissions due to Passenger Transportation Freight Transportation Model: –(P) x (FTM/P) x (VMT/FTM) x (Fuel/VMT) x (Carbon/Fuel) = Carbon Emissions due to Freight Transportation Some modes of transportation did not have adequate data, so the model had to be shortened by 1 factor. For example, Fuel/PMT would replace (VMT/PMT) x (Fuel/VMT).

6. Historical Transportation Sector Carbon Emissions from 1960-2004 Dashed line represents a more comprehensive second source, EIA, computed by fuel type as opposed to mode of transportation

7. Historical Passenger Transportation Carbon Emissions from 1960-2004 Passenger cars contribute the most in passenger transportation carbon emissions

8. Historical Passenger Transportation Carbon Emissions from 1960-2004 Light trucks and urban rail have the highest growth rates in passenger transportation

9. Historical Freight Transportation Carbon Emissions from 1960-2004 Combination trucks contribute the most in freight transportation carbon emissions

10. Historical Freight Transportation Carbon Emissions from 1960-2004 Combination trucks also have the highest growth rate in freight transportation, followed by air carrier and rail

11. Projected Transportation Carbon Emissions from 1960-2004 Carbon emissions for 9 modes of transportation were projected out to 2050, normalized at 1990: 1.Passenger Car 2.Light Truck 3.Air Carrier (Passenger) 4.Bus, Total (Passenger) 5.Rail, Total (Passenger) 6.Combination Truck 7.Air Carrier (Freight) 8.Rail (Freight) 9.Water (Domestic Vessels only) All 9 models assumed the same annual growth rates for their causality factors for easy comparison: –PMT/P or FTM/P = 0.5% –VMT/PMT or VMT/FTM = 0.5% –Fuel/VMT or Fuel/FTM = -1.0% The negative growth rate means better fuel efficiency

12. Projected Passenger Car Carbon Emissions

13. Projected Light Truck Carbon Emissions

14. Projected Air (Passenger) Carbon Emissions

15. Projected Total Bus Carbon Emissions

16. Projected Total Rail (Passenger) Carbon Emissions

17. Projected Combination Truck Carbon Emissions

18. Projected Air (Freight) Carbon Emissions

19. Projected Rail (Freight) Carbon Emissions

20. Projected US Water Carbon Emissions

21. Parameters influencing the carbon emissions factor The trend of the carbon emissions factor (Carbon/Energy) was assumed to be constant. Its parameters are: 1.Type of Fuel Used 2.Carbon Content Given Type of Fuel Used

22. Suggestions to improve the carbon emissions factor Buy hybrid cars Given a regular gasoline car, one could find gas stations with lower carbon content fuels Be active in pushing for laws that would lower the carbon content of all types of fuels Research on developing lower carbon content fuels Educate people about importance of energy efficiency in vehicles

23. References Indicators of energy transportation sector data –http://intensityindicators.pnl.gov/trend_data.stmhttp://intensityindicators.pnl.gov/trend_data.stm Energy Information Administration –http://www.eia.doe.gov/http://www.eia.doe.gov/ –http://www.eia.doe.gov/emeu/efficiency/ee_repo rt_html.htmhttp://www.eia.doe.gov/emeu/efficiency/ee_repo rt_html.htm Bureau of Transportation Statistics