The combustion of petroleum based fuels in transport leads to the emission of greenhouse gases.
In the guide below, we outline the carbon footprint of the different modes and types of transport, such as road, air, water, and rail transport.
Summary – Carbon Footprint By Type Of Transport
Firstly, What Is A Carbon Footprint?
Read more about carbon footprints in this guide
General Emission Trends In Transport From The Data
General emissions trends from the data in the guide below might be:
– Passenger cars and light trucks are the main emitting types of transport in total, with heavy trucks and freight behind them
– Emissions rates (which are different to emission totals) of the different types of transport can vary, depending on several variables and factors
We discuss emission rates of the different types of transport below
– Most emissions comes from petroleum-based fuel products (like gasoline), generally in internal combustion engines
– Most emissions happen mainly at the operation stage of a vehicle when it is burning/combusting fossil fuel based fuel
– Total emissions from transport are not decreasing because the total number of miles or kilometres being driven per year are not decreasing (and in some countries, total vehicle numbers aren’t decreasing either)
There’s an increasing demand for transport essentially
There may also be other ways to express emission trends from transport other than what is listed above.
Points Related To Emissions In Transport Covered In This Guide
In the guide below, we cover the following points:
– What % of all emissions transport is responsible for as a sector
– The different ways to measure or express emissions in transport
– The different types of transport
– Which types of transport are responsible for the most emissions globally, and also in the US, and in Canada
– Which types of transport emit the most, per passenger, per unit of distance travelled
– Which types of transport emit the most, per unit of distance travelled
– The average emissions rate and quantity of the average passenger vehicle
– The types of greenhouse gases of the average passenger vehicle emits
– The carbon footprint of electric vs hybrid vs hydrogen cars
– The types of fuels (and engine systems) that are responsible for the most greenhouse gas emissions
– The lifecycle stage that most transport emissions occur at
– The potential carbon footprint of a Tesla
– The potential carbon footprint of a Prius
– What’s been the trend of transport related emissions, and what might this mean for the future?
– Different factors and variables that can impact emissions from transport
– Potential solutions for reducing emissions in transport
– Other potential environmental issues arising from transport
Potential Environmental Impact Of The Transport Sector
What % Of Greenhouse Gas Emissions Is Transport As A Sector Responsible For?
Transport might be the largest greenhouse gas emitter of any sector in the US
Based on the data below, transport might be responsible for between 28 to 33% of total emissions in the US.
In 2018, greenhouse gas emissions from transportation accounted for about 28.2 percent of total U.S. greenhouse gas emissions, making it the largest contributor of U.S. greenhouse gas emissions (epa.gov)
The four largest generators of CO2 in the U.S. are: Heating and cooling homes (21%), Heating and cooling buildings (18%), Driving cars and trucks (33%), and Industrial operations (28%) (nrmca.org)
In Europe, road transport alone might be responsible for roughly one fifth to one quarter of total carbon dioxide emissions.
ec.europa.eu indicates that in Europe:
Road transport contributes about one-fifth of the EU’s total emissions of carbon dioxide (CO2), the main greenhouse gas.
Light-duty vehicles – cars and vans – produce around 15% of the EU’s emissions of CO2 [and] Heavy-duty vehicles – trucks and buses – are responsible for about a quarter of CO2 emissions from road transport in the EU and for some 6% of total EU emissions.
Different Ways To Measure Emissions In Transport
There’s different ways to measure emissions from different types of transport
A few ways include, but aren’t limited to:
1. Total emissions or % share of emissions
2. Emissions (CO2e) per passenger mile or CO2e per mile, and,
3. The carbon intensity of a particular mode of transport or fuel (e.g. how much carbon it emits per gallon of fuel for example)
The Different Types Of Transport
There’s different types of transport to consider – on the road, water, rail, in the the air, and so on.
On the road, there’s mainly passenger vehicles and trucks (light trucks, and heavy trucks), but also motorbikes, buses, and other road transport.
On the water, there’s ships and ferries.
In the air, there’s planes.
On rails, there’s trains and trams.
There’s even new types of transport like electric bikes, scooters, and skateboards.
There’s also another category of transport to consider – passenger vs freight (and delivery) vehicles.
Non powered transport includes things such as bikes, and even walking.
Which Types Of Transport Are Responsible For The Most Greenhouse Emissions Globally?
Cars and trucks by far emit the most greenhouse gas emissions of any type of transport globally in the transport sector.
In terms of total global emissions, the forms of transport that emit the most GHGs are:
Cars – 40%
Trucks – 34%
[Followed by Planes at 11%, Boats at 11%, and Trains at 4%]
Which Types Of Transport Are Responsible For The Most Greenhouse Emissions In The US?
In the US, passenger cars and light duty trucks make up over half of transport related greenhouse emissions, and, when adding heavy duty trucks, some estimates put that figure at 83%.
Cars and light trucks might also make up 17% of all emissions in the US (across all sectors and industries).
Emissions From Transport Sector
From epa.gov, in the US:
The largest sources of transportation-related greenhouse gas emissions include passenger cars and light-duty trucks, including sport utility vehicles, pickup trucks, and minivans [, and,] These sources account for over half of the emissions from the transportation sector.
The remaining greenhouse gas emissions from the transportation sector come from other modes of transportation, including freight trucks, commercial aircraft, ships, boats, and trains, as well as pipelines and lubricants.
From css.umich.edu, in the US:
Passenger cars, light duty trucks and medium or heavy duty trucks emit around 83% of transportation greenhouse gases.
Commercial aircrafts (7%), rail, ships and boats, motorcycles and buses and other transportation make up the rest
From css.umich.edu, in the US:
[And, when looking at all emissions in the US,] Cars and light trucks make up about 17% of total greenhouse gas emissions in the US (as of 2016).
What Types Of Transport Are Responsible For The Most Emissions In Canada?
In Canada, passenger transport makes up the most transport related emissions, followed by freight
[In Canada] Passenger transportation contributes 54% to total emissions, freight emissions are 41% of total and off-road is 5% (nrcan.gc.ca)
Emissions From Different Types Of Transport – Per Passenger, Per Unit Of Distance Travelled
Emissions per passenger, per unit of distance travelled takes into consideration:
The total number of passengers sharing a vehicle, and total distance travelled by that vehicle (such as miles or kilometres)
For example, if a car travels a certain distance with 4 people in it compared to 1 person, there’s a more efficient per passenger per mile or kilometre emission number (as the 4 people are sharing the same car, as opposed to using 4 different cars)
The data below suggests that bikes are most efficient, with trains in second
Planes are the least efficient, followed by ships
Obviously the number of people that each type of transport is assumed to carry matters with these results, but, the type of vehicle, the fuel they are using, and other factors play a role too
For planes specifically, there’s a range of factors that impact a plane’s emission rate, but, short plane trips generally emit more than long distance flights
For trains specifically, commuter and long distance trains might have similar emissions rates, and, electrified trains in cities with cleaner energy grids might have lower emissions than regular trains
For ferries specifically, the higher the knots on the ferry, the more it emits
When comparing planes, trains, and ferries, the average commercial plane flight might emit more than trains on a per passenger mile basis. Ferries however have a lower emissions rate than both of them.
All Types Of Transport – In Europe
From wikipedia.org, the numbers below are for grams of CO2 emissions, per passenger kilometre, in Europe:
[The most efficient forms of transport are Bikes (carrying 1 passenger average) at 0 gCO2 (per passenger kilometre), Trains (carrying a 156 passenger average) at 14 gCO2 (per passenger kilometre), Small Cars (carrying 4) at 42 gCO2, Big Cars (carrying 4) at 55 gCO2, Buses (carrying 12.7) at 68 gCO2, and Motorbike s(carrying 1.2) at 72 gCO2]
[The least efficient forms of transport are Planes (carrying 88) at 285 gCO2, Ships at 245 gCO2, Big Cars (carrying 1.5) at 158 gCO2, and Small Cars (carrying 1.5) at 104 gCO2]
What is not considered in the numbers above is transport such as small electric scooters and electric skateboards.
In 2016, the average domestic commercial flight emitted 0.39 pounds of CO2e per passenger mile.
[Plane emissions are] affected by aircraft type, the length of trip, occupancy rates, and passenger and cargo weight
[For] Domestic, short distance [that are] less than 463 km (288 mi) [the emission rate is] 257 g/km CO2 or 259 g/km (14.7 oz/mile) CO2e [259 grams is about 0.57 pounds]
[For] Long distance flights [the emission rate is] 113 g/km CO2 or 114 g/km (6.5 oz/mile) CO2e [114 grams is about 0.25 pounds]
On average, trains release 0.31 pounds of CO2e per passenger mile (css.umich.edu)
On average, commuter rail and subway trains emit 0.17 kg of CO2 per passenger mile (0.11 kg/km per passenger) [0.17kg is about 0.37 pounds]
… long distance (>20 mi, >32 km) trains emit 0.19 kg of CO2 per passenger mile (0.12 kg/km per passenger) [0.19kg is about 0.41 pounds]
[Regular trains can be two to eight times higher emitting than electrified trains in some cities according to some sets of data]
Average carbon dioxide emissions by ferries per passenger-kilometre seem to be 0.12 kg (4.2 oz). [0.19kg is about 0.26 pounds]
[However, 18 knot ferries, and 24–27-knot ferries can produce a lot more]
The wikipedia.org resources have a lot more information on CO2e per distance travelled, and per passenger distance travelled.
Emissions From Different Types Of Transport – Per Kilometre Or Mile Travelled
Apart from CO2e rates per passenger mile or kilometre, some reports provide flat CO2e rates per mile or kilometre for a vehicle regardless of the number of people it carries.
The wikipedia.org resource does this for road transport and other types of transport.
In one set of European data, light commercial vehicles emit the most, followed by new passenger cars, and hybrid electric cars emitted the least.
Another set of US data showed trucks emitted more than passenger cars.
Emissions For The Average Passenger Vehicle
The typical passenger vehicle might:
– Emit 0.78 to 0.89 pounds of CO2 from the tailpipe per mile travelled
– Emit 4 to 9 metric tons of CO2 a year
– Emit 126,000 pounds of CO2e over it’s lifetime
This data though is obviously heavily dependent on specific variables and assumptions used.
In addition to the above, majority of GHGs emitted from the average passenger vehicle might be CO2, and, they might mostly come from the combustion of petroleum based fuel products in internal combustion engines.
Per Mile Emissions
Tailpipe CO2 created from driving one mile [with] The average passenger vehicle emits about 404 grams of CO2 per mile [and, 404 grams is about 0.89 pounds] (epa.gov)
The average passenger car emits 0.78 pounds of CO2 per mile driven (css.umich.edu)
… A typical passenger vehicle emits about 4.6 metric tons of carbon dioxide per year.
This assumes the average gasoline vehicle on the road today has a fuel economy of about 22.0 miles per gallon and drives around 11,500 miles per year.
If you’re commuting 7800 miles each year in your car (based on 30 miles a day for work) … And if you drive a car that gets 22 miles to the gallon every weekday, your annual carbon footprint from commuting is 4.3 metric tons (livescience.com)
Burning one gallon of gasoline creates about 20 pounds of CO2—which means the average vehicle creates roughly 6 to 9 tons of CO2 each year (c2es.org)
Emissions Over Lifetime Of Car
… roughly 126,000 pounds of CO2e [are] emitted in a car’s lifetime (assuming 120,000 miles for a 1995 mid-sized sedan) (css.umich.edu)
Greenhouse Gases Emitted
For a typical passenger vehicle … The majority of greenhouse gas emissions from transportation are carbon dioxide (CO2) emissions …
[… In addition to carbon dioxide (CO2), automobiles produce methane (CH4) and nitrous oxide (N2O) from the tailpipe and hydrofluorocarbon emissions from leaking air conditioners. The emissions of these gases are small in comparison to CO2 though]
Where GHGs Mainly Come From
[Majority of GHGs are a result of] the combustion of petroleum-based products, like gasoline, in internal combustion engines (epa.gov)
For a typical passenger vehicle, you also have the indirect carbon footprint of making the car itself, and extracting, pumping and transporting to get the oil to refineries and service stations
Carbon Footprint Of Electric, Hybrid & Hydrogen Cars
The carbon footprint of electric vehicles depends on factors like how large the car is, but also how clean the energy source is that the car gets it’s electricity from.
Cleaner energy grids might mean lower carbon footprints for electric vehicles, whereas energy grids using primarily fossil fuels might result in higher carbon footprints.
You also have to look at the individual features of the car, such as how many Wh/kilometre (or mile) the car gets from it’s battery.
The emissions of hybrid vehicles depends on the type of hybrid vehicle it is, it’s features and the system it uses, and the amount of electricity or gasoline it uses.
It also matters where it gets it’s electricity from if it uses electricity.
So, hybrid vehicles can have varying carbon footprints.
A fuel efficient hybrid vehicle might be more carbon efficient than an older internal combustion engine vehicle running on gasoline for example.
Hydrogen Fuel Cell Cars
A hydrogen fuel cell vehicle emits only water vapor during operation, but, like an electric vehicle, it needs a primary energy source to make the hydrogen fuel.
This energy source has a carbon footprint, especially when it’s a fossil fuel.
Where the primary energy source used to produce hydrogen is a fossil fuel like natural gas, the carbon footprint might be higher.
It’s worth mentioning that some reports indicate that a car running on hydrogen has a lower carbon footprint compared to a conventional internal combustion engine vehicle, and hydrogen also has better fuel efficiency than gasoline
The Type Of Transport Fuel (& Engine System) That’s Responsible For The Most Greenhouse Gas Emissions
Apart from the type or mode of transport, the type of fuel or energy source used for a vehicle also contributes to emissions.
For example, with road transport, gasoline, diesel and cars running on electricity, might all have different emission rates.
The type of engine or battery system the car uses can also matter, like for example when comparing an internal combustion engine vs an electric car battery and electric motor.
From the data below:
Petroleum based fuel (like gasoline and diesel) is the most common fuel
Petroleum-based products (like gasoline) in internal combustion engines emit the most GHGs, whilst natural gas might emit less as a fuel
Diesel emits more per gallon than gasoline, but diesel has better fuel economy. So, more distance can be achieved out of a gallon.
Most Commonly Used Car Fuel
Over 90 percent of the fuel used for transportation [in the US] is petroleum based, which includes gasoline and diesel (epa.gov)
Types Of Transport Fuel & Engines Responsible For The Most Emissions
Considering only tailpipe emissions, natural gas also emits 15 to 20 percent less heat-trapping gases than gasoline when burned in today’s typical vehicle (ucsusa.org)
In the United States … the majority of greenhouse gas emissions from transportation are carbon dioxide (CO2) emissions resulting from the combustion of petroleum-based products, like gasoline, in internal combustion engines (epa.gov)
Emissions Rates & Efficiency Of Different Fuel Types
Gasoline releases 19.6 pounds of CO2 per gallon when burned, compared to 22.4 pounds per gallon for diesel … However, diesel has 11% more BTU per gallon, which improves its fuel economy (css.umich.edu)
For a typical passenger vehicle… the tailpipe CO2 created from burning one gallon of fuel … are:
… CO2 Emissions from a gallon of gasoline: 8,887 grams CO2/ gallon
… CO2 Emissions from a gallon of diesel: 10,180 grams CO2/ gallon
Burning one gallon of gasoline creates about 20 pounds of CO2 … (c2es.org)
[In Australia] Every litre of unleaded petrol consumed generates around 2.5kg* of greenhouse gas (measured in CO2-e or carbon dioxide equivalent), one litre of diesel fuel generates about 2.9kg* CO2-e and LPG 1.7kg* CO2-e (greenfleet.com.au)
Emissions From Different Energy Sources
Energy sources will be more important in the future as more electric vehicles from example are on the roads, and electricity they use will need an energy source.
Read more about the different energy sources and their emission rates in this guide.
At What Lifecycle Stage Do Majority Of Car Emissions Occur?
Most of the carbon footprint of a regular passenger car comes from the driving/operation stage.
There are indirect emissions to consider at other stages too though – such as the car manufacturing stage.
Whilst it is estimated that around 80-90% of emissions happen at the vehicle usage stage whilst burning fuel, all vehicles have a carbon footprint at their manufacturing stage too (indirect emissions), and this is where the remainder of emissions might come from for cars
For electric cars, direct emissions happen when electricity is generated (at a power plant, or somewhere else).
What Stage Majority Of Car Emissions Occur At
Of the roughly 126,000 pounds of CO2e emitted in a car’s lifetime (assuming 120,000 miles for a 1995 mid-sized sedan), 86% is from burning fuel (css.umich.edu)
The direct carbon footprint can be measured from tailpipe emissions, or in the case of electric cars, the emissions from the energy source (css.umich.edu)
Can come from mining and sourcing materials, manufacture, shipping and transporting, pumping and refining, maintenance and servicing of the car, and waste disposal.
Every time you buy a new car, you effectively mine 3-7g of “platinum group metals” to coat the catalytic converter [and] The six elements in the platinum group have the greatest environmental impact of all metals, and producing just one kilo requires the emission of thousands of kilos of CO₂ (theconversation.com)
streets.mn and drivetribe.com both outline the impact of production carbon footprints, but drivetribe.com also outlines the impact of making batteries and shipping.
Potential Carbon Footprint Of A Tesla
The carbon footprint of a Tesla depends on a range of factors.
An example of one of those factors might be the type of Tesla you buy, as some Teslas for example can solar charge from their roof for example, and others have better power efficiency or capability.
Car size, wheel size, whether it’s front vs rear wheel drive, battery size, drive range per charge, are some examples of other factors.
Future factors like new models, new designs and features, new technology and so on may also impact the carbon footprint of Teslas.
From the data below:
A Tesla S may have a carbon emissions rate of 222g of carbon per kilometre driven
A Tesla S may have a larger manufacturing footprint than an internal combustion engine car, but, a Tesla can recycle it’s battery, and, there might be a large emissions reduction of a Tesla S over an internal combustion engine car during driving
Carbon Footprint Of A Tesla S
Some people have had their Tesla S models independently tested to provide 444 watt hour per kilometre (Wh/km)
When applying a 0.5 g CO2/Wh for electric energy consumption, the Tesla S car has carbon emissions of 222g/km
Carbon Footprint Of A Tesla vs Internal Combustion Engine Vehicle
From forbes.com, when comparing a Tesla’s carbon footprint vs internal combustion vehicles including hybrids …:
… the manufacturing of a full-sized Tesla Model S rear-wheel drive car with an 85 KWH battery was equivalent to a full-sized internal combustion car except for the battery, which added 15% or one metric ton of CO2 emissions to the total manufacturing.
… this was trivial compared to the emissions avoided due to not burning fossil fuels to move the car [where] Tesla has a 53% carbon footprint reduction, even when taking into account the usually coal fuelled electricity a Tesla uses to power the battery
Tesla are also able to recycle their batteries into completely reusable materials and substantially reduce the carbon footprint of manufacturing Lithium-ion batteries [and] Unicore are able to recover 70% of the carbon in the end of battery lifecycle
The popularmechanics.com resource in the resources list at the bottom of this guide has more information about challenging carbon myths about Teslas.
Potential Carbon Footprint Of A Prius
From the data below:
– Newer Prius’ might be getting more emissions efficient
– Some all electric cars might have a lower carbon footprint than some models of Prius’
– Some Prius’ might be have a lower carbon footprint than a Tesla at the beginning of their lifecycle, but, a Tesla may end up with the lower carbon footprint after a certain amount of miles/kilometres driven
– Prius’ may have some limitations with achieving long term emissions targets and goals
Trend For Prius Emissions
Per wikipedia.org, each new generation of the Prius produces less emissions per mile driven.
Carbon Footprint Of Latest Prius Model
According to the Toyota website as of March 2021, the latest featured Prius model ‘rated at 3.4L/100km for combined fuel economy and 80g/km for combined CO2’
Carbon Footprint Of Prius Prime
According to greencarreports.com: ‘[the Prius Prime emits] 181 grams of CO2 per mile [but] several all-electric cars proved even greener than the Prius Prime over their full life cycles, including the Tesla Model 3, the Chevy Bolt EV, Nissan Leaf, and Ford Focus Electric’
Carbon Footprint Of Prius vs Tesla
streets.mn has an article worth reading which shows on a graph that a 2020 Prius starts off more carbon friendly from an emissions perspective than a Tesla 2020 Model Y, but the Model Y ends up slightly ahead overall after 100,000 miles driven.
Potential Limitations With Relying On Prius’ For Emissions Reductions
Two other articles worth reading are from drivetribe.com and greencarreports.com though – they both outline why Prius’ aren’t the perfect solution to transport related emissions, by outlining some limitations.
What Is The Trend Of Transport Related Emissions Over Time?
From the data below:
– Total transport related emissions are increasing over time globally, and in certain countries and regions
– Total vehicle miles travelled/driven are increasing over time
– Average new vehicle economy has improved over time
So, it might be accurate to say that fuel economy and fuel efficiency improvements are not having a positive impact on emissions. The same might be said for decreased tailpipe emission rates.
This is because the total distance travelled is increasing.
Demand for travel, population growth, economic growth, urban sprawl, and periods of low fuel prices are examples of factors that can increase total emissions, and total vehicle miles travelled.
On the biggest scale, total emissions are influenced by the total number of vehicles on the road, and total number of miles driven by all vehicles
Total Transport Related Emissions
In terms of the overall trend, from 1990 to 2018, total transportation emissions have increased due, in large part, to increased demand for travel (epa.gov)
Total Number Of Vehicle Miles Travelled/Driven
The number of vehicle miles traveled (VMT) by light-duty motor vehicles (passenger cars and light-duty trucks) increased by 46.1 percent from 1990 to 2018 … (epa.gov)
… total annual vehicle-miles driven have increased by more than 140 percent since 1970 (pollutionissues.com)
Average New Vehicle Fuel Economy
[Average new vehicle fuel economy has improved every year since 2005] (epa.gov)
Emissions Trends In Transport Specifically In Europe
emissions … are still 20.5% higher [in 2012] than in 1990 [and] Transport is the only major sector in the EU where greenhouse gas emissions are still rising (ec.europa.eu)
Different Factors & Variables That Can Impact Emissions From Transport
There a both general, and specific factors and variables that can affect the emission totals and emission rates from different modes of transport.
Some of these factors are specific to the driver and the individual vehicle, whilst some are external factors
Emissions numbers can vary between cities and countries, and even based on assumptions and data used in calculations
Some factors might include:
Variables that lead to different emission rates are the type of fuel used, emission regulations and laws in an area, the brand, model and features of the car, and how fuel efficient the car is (technology and weight of the car might play a role here).
The total number of cars on the road also matters, along with the total distance being driven by all vehicles
Aviation & Air
The length of the flight
Longer flights can be more efficient because the take off energy is averaged out with more distance travelled.
But, shorter flights may lead to less total emissions
There are different factors and variables that ultimately determine each aircraft’s emission rate
Water & Ferries
For sea transport, the carbon intensity can depend on how many knots the ferry or ship is travelling at
Inner city buses emit greater rates of GHGs compared to outer city long distance buses.
How often a bus has to stop, and traffic jams, detours, and pit-stops can all impact emission rates and efficiency.
Trains & Rail
Commuter trains emit at a lower rate than long distance trains
Also, detours, and stop-overs add to total emissions.
How many people does the train hold in total?
Rail emissions per passenger kilometer can differ from country to country, and depending on whether the rail is electrified or not, and how clean the electricity is
Electrified trains may have different carbon footprints to other trains
Shipping & Delivery Vehicles
Delivery vans and trucks tend to have lower emission rates than big rig transport boats and vessels.
When measuring by kg of CO2 per Ton-Mile, air cargo is the worst emitter, followed by trucks, trains, and sea freight last.
The type of vehicle (car, truck, etc)
The brand and model of the vehicle
The size of the vehicle
How many passengers the vehicle can hold
The fuel used by the vehicle (gasoline vs diesel for example)
The fuel efficiency (how many miles per gallon it gets, or, how many miles per charge it gets)
Whether it uses an internal combustion engine, or an electric battery with an electric motor
The conditions the vehicle is driven in
How the vehicle is driven (e.g. slow stop-starting in a city vs faster consistent driving on a highway vs redlining on a race track)
How clean the electricity source is if it’s an electric car
The condition of the vehicle – how well maintained it is
Individual features and design of the car such as the size or width of the tires, regenerative braking, tailpipe carbon capture technology and so on
The weight and load on the vehicle
Options/accessories fitted to the vehicle
Factors and variables that might vary throughout the whole lifecycle and all stages of the vehicle (sourcing and mining of materials, manufacturing, shipping, operation, waste disposal, and so on)
Large Scale Variables
Total distance covered by all vehicles (total miles or kilometres)
Total number of individual vehicles on roads, in the air, in the water, and so on
The carbon footprint of a vehicle varies depending on the type of vehicle it is (css.umich.edu)
Potential Solutions For Reducing Emissions In The Transport Sector
It’s worth noting that more sustainable transport has several potential solutions (that currently involve trade offs) that might help address emissions and also air pollution
But, total number of vehicles and total distance travelled per year also matters, because more total miles by all vehicles, generally equals more emissions overall.
Other Potential Environmental Issues Arising From Transport
In transport, the emission of air pollutants that contribute to outdoor air pollution is a separate issue to the emission of greenhouse gases that contributes to a changing climate.
Regular air pollutants from transport include particulates, carbon monoxide, ozone and other air contaminants that decrease air quality and can impact human health.
The potential solutions for reducing air pollutant emissions from vehicles are similar to those suggested for reducing greenhouse gas emissions from vehicles (as both result from the burning of fossil fuels as a main source of the emissions and pollution)
You can read more about the full impact of transport and vehicles on the environment in this guide.
2. Various ‘Better Meets Reality’ guides
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