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Local Travel Emissions

1. What is Local Travel? Local travel includes trips to work, school or daycare, as well as trips for shopping, entertainment, services, personal business and local visits to friends and family. Local travel does not include trips taken for business purposes. Business trips are taken for commercial purposes and are not counted as part of your personal greenhouse gas emissions. Local travel takes place within your community or, if you live in the country, are part of your general routine trips. Unless you live in a large metropolitan area or in the country, most of these trips are of a relatively short distance (less than 25 kilometres round trip).

2. What is "round trip distance"? Round trip distance is the total distance you travel for one trip, from when you leave your home to when you return to your home. One trip can be a trip to the store and back or several small trips "chained" together. For example, if you travel to work or school, then on the way home you stop off at the local store, then go on to visit a friend, and finally return home, that would be considered one trip. Either estimate or use your car's odometer to find out what the total distance was from the time you left home to the time you returned home. This is the "round trip distance." Remember to enter the number of round trips you take IN ONE WEEK!

3. How does my mode of travel affect emissions? Your mode of travel (the type of vehicle you travel in) can make a big difference in terms of your greenhouse gas emissions. Your mode of travel (the type of vehicle you travel in) can make a big difference in terms of your greenhouse gas emissions. There are several vehicle types you can choose in the Climate Change Calculator: • bicycle • city bus • subway • light rail • commuter train • car You can also choose to walk. What you will notice when you look at the list of modes in the climate change calculator is that the type of car or cars you have will be shown at the bottom of the list. The climate change calculator automatically takes the information about your car(s) that you provided in the "user definition" screen and places it in the list. The different modes shown will produce different amounts of greenhouse gas emissions for every kilometre travelled. For example, walking and taking your bicycle produce no greenhouse gas emissions at all, no matter how far you travel. Public transit (city buses, subways, light rail systems and commuter trains) usually produces fewer emissions per kilometre travelled than cars. For example, a diesel city bus produces about 156 grams of greenhouse gases for every passenger travelling one kilometre. The comparable figure for subways is about 34 grams, for commuter trains about 55 grams and for light rail about 21 grams. On the other hand, one person travelling in a small car produces about 259 grams of greenhouse gases for every kilometre travelled, in a mid-size car, 316 grams, and in a mini-van, sport-utility vehicle or big car, 460 grams. However, if those choosing to drive their cars decide to take passengers, their personal greenhouse gas emissions drop substantially. With just one passenger, car emissions are cut in half, with two passengers, they are cut by two thirds. Many people choose to drive their cars to work, usually without anyone else in the car. This is a major source of greenhouse gas emissions, urban smog and other air pollution problems, not to mention traffic jams. There are several ways you can reduce greenhouse gas emissions from taking your car to work or school. One of the best ways is to find a friend (or better yet, several friends) travelling in the same direction and give them a ride! If this is difficult or impossible, use public transit if you can.

4. How does vehicle occupancy affect emissions? Vehicle occupancy means the total number of people riding in the vehicle. For example, if you are driving your car alone, your vehicle's occupancy is 1. If you have one passenger, your vehicle's occupancy is 2, and so on. If you are the only passenger in a car, then the vehicle occupancy is 2 (you and the driver). The Climate Change Calculator lets you see how your personal emissions change as the number of people riding in the vehicle changes. When you choose a mode, the calculator automatically selects an occupancy appropriate to the type of vehicle. For example, studies have shown that a city bus has, on average, 9 passengers riding in it. By contrast, subways and commuter trains have, on average, 20 passengers per car and light rail systems have 31 passengers per car. Cars and bicycles are assumed to have only one occupant (the driver) and, of course, unless you are carrying someone on your back, you are walking as a single person! The calculator lets you change the occupancy of the vehicle you are travelling in. If you take the bus to school or to work during rush hour, you may find that it is always full. If you think it always has more than 9 occupants, change the occupancy in the scroll box to the right of the screen and see how this changes your personal emissions. If you ride to work or school every day by yourself, but would like to see how riding with a friend to work every day would change your personal emissions, change the occupancy to two and see what happens!

5. What is "modal split"? When you think about all the trips you take in one week, you probably find that some of them are walking trips, some are taken with your bicycle, others are taken using the family car, and still others are taken using public transit. For each of the round trip distance categories, you can choose up to four modes of travel. When you choose more than one mode of travel, the calculator automatically displays a slider bar at the bottom of your screen. This lets you estimate how many of the trips you have taken in that trip distance category are taken by each mode. For example, say you take 10 weekly trips with a total distance of less than 5 kilometres. If you walk to the corner store three times, are driven to school five times, and take your bike to the park twice, then about half of the slider bar would be for your car trips to school, one third of the bar would be for walking trips to the corner store and the rest would be for bike trips to the park. The calculator will automatically calculate your personal emissions based on the modal split you choose.

6. How are my local travel emissions calculated? The amount of fuel needed to move a car of a certain size, a city bus, subway or light rail car one kilometre is fairly well established by scientific study. For each trip distance category, the average distance is taken. For example, trips in the "less than 5 km" category are assumed to be 2.5 kilometres in length. The trip length is then multiplied by the amount of fuel needed to move the vehicle type you chose one kilometre. The amount of fuel used is then multiplied by an "emissions factor" - the known amount of greenhouse gases produced when, say, a litre of gasoline or a kilowatt-hour of electricity is consumed. These emissions factors have been established by scientific studies. The emissions to move the vehicle are then multiplied by the total number of trips taken in the distance category. Finally, the total emissions are then divided by the number of occupants in the vehicle. If you chose more than one mode, the total emissions for each vehicle type are multiplied by the fraction of total trips taken by that mode. These numbers are then added together to arrive at your total personal emissions from travel in that trip distance category. This process is repeated for each trip distance category. Then the emissions are added together and shown on your personal emissions bar at the top of the screen.