So what exactly is a carbon footprint? In simplest terms, carbon footprint is the total amount of greenhouse gases produced by various human activities within a given time frame. Carbon footprint is usually measured in tons of carbon dioxide (CO2) released into the atmosphere. Your home has a carbon footprint if you use oil, coal or gas to heat it. That cheeseburger at your favorite restaurant has a carbon footprint: raising the beef and wheat and operating the restaurant all involves greenhouse gases. Your car has a carbon footprint, dependent on the vehicle’s fuel consumption and driving distance.
Transportation accounts for 31% of the annual carbon dioxide emissions in the United States. Annual emissions in the U.S. are around 5 million kilotons, meaning cars account for 1,550,000 kilotons of carbon dioxide emissions every year. By comparison, electricity accounts for 37% of total emissions, industry 15%, and residential and commercial use 10% — less than a third that of automobiles nationwide.
Why is carbon footprint important? Carbon dioxide emissions are offset by natural features of the environment, like forests, which remove CO2 from the atmosphere. However, large amounts of CO2 emissions outstrip the ability of these natural sources to exchange CO2 for oxygen. Changes in the amount of CO2 in the atmosphere changes the amount of heat retained by the earth’s atmosphere (the “greenhouse effect”), which in turn can effect changes in the global climate.
- List of Countries by Carbon Dioxide Emissions from Wikipedia
- Map of Carbon Footprints from Business Insider
- Carbon Footprint of Typical U.S. Household
- How Does Your Car Affect Your Carbon Footprint?
The Lowdown: Cars and the Carbon Footprint
Can the car you drive, the condition the car is in, or even choosing to drive it make a difference in carbon footprint? The answer is yes. Every gallon of gas burned releases 24 pounds of CO2 into the atmosphere. Taking the bus, walking, or riding your bike could account for hundreds of pounds of carbon dioxide a day. The average American releases 19 tons of CO2 into the atmosphere every year. Cutting down even a fraction of that could make a huge difference.
If you do drive, however, fuel efficiency is the biggest indicator of your car’s carbon footprint. The more miles per gallon your car gets, the less carbon dioxide it will pump into the air. In general, this means that smaller, more fuel-efficient cars will have a much smaller carbon footprint than a large SUV.
The true carbon footprint of a vehicle can be a little more complicated than that, however. Common wisdom suggests that newer cars generally have a smaller carbon footprint and are easier on the environment. This is certainly true for hybrids and electric cars, which have been gaining in popularity. But studies have shown that the manufacturing of a car accounts for about 30% of its carbon footprint over its lifespan.
This means that driving an older used car might actually have less of an impact on the environment than buying new. And though hybrids and electric cars provide an appealing alternative to traditional transportation, neither are perfect. Hybrids in particular feature batteries with a significant environmental impact compared to non-hybrids. Electric cars might seem emission-free on the surface, but that’s only true if the energy source they use to recharge is itself renewable.
- Carbon Footprint: Hybrid vs. Gasoline vs. Electric
- Study of Electric and Hybrid Cars from Green Car Congress
- Vehicle emission calculator from Climate Friendly
- Reducing Car Travel Emissions
- Top 10 Lowest Carbon Cars of 2014
Carbon emissions make a demonstrable effect on the environment. More CO2 in the atmosphere means the atmosphere retains more heat. This, in turn, leads to warmer land temperatures and sea water, which in turn has led to the melting of glaciers and the global rise of sea levels. Consequences of climate change include heat waves, flooding, and extreme weather, as well as an impact on the availability of fresh water.
How does this relate to you and your car? It all comes back to the average carbon footprint. The average per capita carbon footprint is 6 tons per year. In the U.S. the average is 20 tons per year, and a third of that is created by automobile emissions — meaning your car itself can put out over 6 tons of C02 a year — enough for two people.
- Global Warming for Beginners in Nine Points
- Car Pollution and Environmental Impact from Carenvironment
- Environmental Impact of Cars Infographic from Planetsave
- How Cars Affect the Ozone Layer from SFGate
- Study on Hybrid Cars from Worcester Polytechnic Institute
- Environmental Impact of Cars and Trains from Carbusters
How A Carbon Footprint is Measured
A carbon footprint comes down to choices. Your carbon footprint is a rough measure of how many tons of carbon your choices (whether related to your car, your diet, or your environment) put into the atmosphere. Factors will include:
- The number of people in your household
- What kind of home you live in
- The efficiency of your lighting, heating and cooling
- How much meat and organic food you have in your diet
- Your recycling and waste management habits
- What kind of car you own and how much you drive.
There are many free online tools to make estimating your carbon footprint easy:
- Carbon Footprint Calculator from Nature.org
- Carbon Footprint Measurement from Carbon Trust
- Measuring Your Carbon Footprint from open.edu (PDF)
- Carbon Footprint from Encyclopedia of Earth
- Carbon Footprint from the University of Colorado Environmental Center
- What is a Carbon Footprint? (The Guardian)
- Measuring Carbon Footprints from Popular Science
Measure Your Own Car’s Carbon Footprint
While there are many tools for factoring your car into your overall carbon footprint, the basic equation remains the same: the average car produces 20 pounds of CO2 for every gallon of gas burned. To measure your car’s carbon footprint yourself, simply determine your gas mileage and figure out how many gallons of gas you burn in a typical day, week or year. This will tell you your car’s basic carbon footprint. Rail, bus and airline travel have their own carbon footprints, which can range from smaller to much larger.
- Carbon Footprint Calculator
- How to Measure Your Company’s Carbon Footprint Easily from Planetsave
- What’s My Carbon Footprint? From Nature Conservancy
- Measure Your Carbon Footprint from Greenshifters
- Transportation Sustainability Tips from Hopkins
- Calculate Your Carbon Footprint from Terrapass
Tips for Reducing Your Car’s Carbon Footprint
Getting your first look at your carbon footprint can be confusing and demoralizing. The good news is, there are many ways you can reduce the carbon footprint of your car, and most of them are pretty easy.
For example: driving the speed limit, maintaining steady speed, and accelerating and decelerating slowly can all save on gas and thus reduce your carbon footprint. Keeping your car well-maintained also helps: replace your oil and air filters, check the tire pressure and keep your tires properly inflated. Consider switching to a lower mileage car insurance — if you drive less and take public transportation (or your bike) more often, your carbon footprint will naturally go down!
Finally, if you are in the market for a new car, consider your options. A new fuel-efficient car might be the best choice, but a used fuel-efficient model might be even better. Hybrids and electrics, though each have their own challenges, provide eco-friendly alternatives to gas-burning vehicles. When selecting a new car, choose the ones with the lowest proven carbon footprint.
Caring for the environment is everyone’s responsibility, but with a little planning and some careful choices, it doesn’t have to be a job.
- Reduce Your Car’s Carbon Footprint from Car Gurus
- 25+ Ways to Reduce Carbon Footprint from COTAP
- How to Reduce Carbon Footprint from Carbonfund
- Tips for Reducing Carbon Footprint from Clackamas
- Carbon Footprint Reduction
- 10 Actions You Can Take Today from Mashable
- Sustainability Tips from Native Energy