Transportation The Earth’s climate has changed many times during the planet’s history, with events ranging from the ice age to long periods of warmth. Historically, natural factors such as volcanic eruptions, changes in the Earth’s orbit and the amount of energy released from the sun have affected the Earth’s climate. Beginning in the late 18th century, human activities associated with the Industrial Revolution also have changed the composition of the atmosphere and are likely influencing the Earth’s climate.

• Buy smart – Before buying a new or used vehicle, or even before renting a vehicle, check out the EPA’s “Green Vehicle Guide” and the jointly run EPA/DOE Fuel Economy Guide Web site at www.epa.gov/greenvehicles
• Drive smart – Many factors affect the fuel economy of your car. To improve fuel economy and reduce greenhouse gas emissions, go easy on the brakes and gas pedal, avoid hard accelerations, reduce time spent idling and unload unnecessary items in your trunk to reduce weight. Gas mileage (MPG), greenhouse gas emissions, air pollution ratings, and safety information for new and used cars and trucks can be researched at www.fueleconomy.gov
• Check your tires – Check your tire pressure regularly. Under-inflation increases tire wear, reduces your fuel economy by up to 3 percent, and leads to increased emissions of greenhouse gases and air pollutants.
• Give your car a break – Use public transportation, carpool or walk or bike whenever possible to avoid using your car. Leaving your car at home just two days a week will reduce greenhouse gas emissions by an average of 1,600 pounds per year. Whenever possible, combine activities and errands into one trip. Try Parking It will help you see your contributions to clean air by giving you an estimate of miles saved and harmful emissions reduced, each time you submit your alternate commute.

Climate change refers to any significant change in measures of climate, such as temperature, precipitation or wind, lasting for an extended period (decades or longer). Climate change may result from:

• Natural factors, such as changes in the sun’s intensity or slow changes in the Earth’s orbit around the sun
• Natural processes within the climate system (e.g. changes in ocean circulation)
• Human activities that change the atmosphere’s composition (e.g. through burning fossil fuels) and the land surface (e.g. deforestation, reforestation, urbanization, desertification, etc.)
• Household Emissions Calculator - You can use the online calculator on the EPA's Web site to get a rough estimate of your personal or family’s greenhouse gas emissions and explore the impact of taking various actions to reduce your emissions.
   

A carbon footprint is a measure of the impact our activities have on the environment, and in particular climate change. It relates to the amount of greenhouse gases produced in our day-to-day lives through burning fossil fuels for electricity, heating and transportation etc. The carbon footprint is a measurement of all greenhouse gases we individually produce and has units of tonnes (or kg) of carbon dioxide equivalent. Click here to calculate yours.

Use Renewable Fuels: Both E85 and biodiesel are renewable fuels that can reduce greenhouse gas emissions from your vehicle. E85 is a fuel blend containing 85 percent ethanol that can be used in certain vehicles called Flex Fuel Vehicles (FFVs). FFVs can be fueled with E85 or with traditional gasoline. There are approximately six million FFVs on the road today. To find out if you own one of them, check the inside of your car’s fuel filler door for an identification sticker or consult your owner’s manual. If you own a diesel vehicle, consider filling up with a biodiesel blend such as B5, a fuel blend containing 5 percent biodiesel. Biodiesel is a renewable fuel made from agricultural resources such as vegetable oils.