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  2. Regulations for Emissions from Vehicles and Engines

Research on the Environmental Impacts of Contrails (Text only)

Both aircraft performance and weather contribute to contrail formation.

Sunrays reflect off contrail clouds.

Contrail clouds block some of the solar waves and retain some of the Earth's energy from escaping.

Aircraft factors:

  • Fuel
  • Engine
  • Aircraft Type
  • Flight Path

Weather factors:

  • Conditions
  • Location
  • Time of Day
  • Time of Year

Regulations for Emissions from Vehicles and Engines

  • Onroad
    • Passenger Vehicles
    • Commercial Trucks & Buses
    • Motorcycles
  • Nonroad
    • Aircraft
    • Heavy Equipment
    • Locomotives
    • Marine
    • Recreational Vehicles
    • Small Equipment & Tools
  • Greenhouse Gas
Contact Us About Regulations for Emissions from Vehicles and Engines
Contact Us About Regulations for Emissions from Vehicles and Engines to ask a question, provide feedback, or report a problem.
Last updated on July 22, 2025
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