How Transportation is a Major Polluter: The Role of Cars, Planes, and Ships

Overview of Global Transportation Emissions

Almost 24% of all CO2 emissions in the world come from transportation, according to the study. The USA had the highest rate of greenhouse gas emissions in the world in 2022. Transportation was responsible for 28% of all emissions in the country, which was the largest single source of emissions. In this sector, there are many different types of cars, planes, ships, and other things. Each of these types contributes differently to the total amount of emissions.

Road transportation: a world centered on cars

The biggest source of pollution from transportation is cars and trucks. According to 2019, about 71.7% of CO₂ emissions from traffic in the European Union came from cars and trucks. Only light-duty vehicles, such as cars and vans, emit more than 3.5 gigatonnes of CO₂ into the atmosphere annually worldwide.


About twenty-five percent of all CO2 emissions in the US come from cars and trucks. For every gallon of gasoline used, about twenty-four pounds of CO2 and other gases that cause global warming are released. This big chunk of GHG pollution is caused by cars and burning fossil fuels. Not only do cars release greenhouse gases (GHGs), but they also release air pollutants like nitrogen oxides (NOₓ) and particulate matter that are bad for people's health.

Pollution from modern airplanes

The airline industry is already a major polluter that has a big effect on radiation, climate change, water use, and ozone damage. It is responsible for 2.5% of all CO2 emissions from aircraft around the world. Additionally, aviation had impacts that went beyond aviation fuel. When fossil fuels are burned, carbon dioxide and other carbon-based pollutants are released into the environment. There are two-thirds of aviation's climate effects that aren't caused by carbon dioxide emissions. These are effects that warm the planet without the carbon dioxide emissions from airplane engines. The effects of waste fully release non-carbon air pollutants along with carbon dioxide, which is a terrible thing because it makes the Earth warmer.

International levels of emissions have gone up by about 146% since 1990, which is a record high for the aircraft industry. Because of this, foreign air travel became one of the most polluting types of aviation very quickly. There is a big problem with lowering pollution because more and more people want to fly, and flying uses a lot of energy.

Pollution from Maritime Transport

About 3% of the world's greenhouse gas emissions are still caused by maritime transport, which is a big number when you think about how much trade happens between countries. These ships mostly use heavy fuel oil, which releases air pollution like sulfur oxides (SOx), nitrogen oxides (NOx), and particulate matter like smoke and fine dust. Such pollution has a direct and negative effect on the health of people living along the coast and the quality of the air.

Environmental Crimes and Their Results

Accidents that happen on ships can be bad for the environment. For example, the recent accident where the oil tanker Stena Immaculate and the cargo ship Solong crashed north of Holland may have caused oil leaks, fires, and the possible release of dangerous materials that could harm marine life. Only these kinds of accidents bring attention to how shipping affects the environment and how dangerous it is.

[Compare and contrast different types of transportation.]

To figure out how different types of transportation affect the environment, we need to look at more than just CO₂ emissions per passenger-kilometer. We also need to look at fuel economy, the use of clean technologies, and a lot of other emissions.

CO₂ Emissions and the Distance Traveled by Each Passenger

When it comes to emissions per mile driven, the different types of transportation leave a big gap. For every kilometer that a train passenger travels, about 14 grams of CO2 are released into the air. On the other hand, for every kilometer that a plane traveler travels, this number is closer to 285 grams. This data is useful for comparison because it shows that flying is much worse for the environment than taking the train.

Low-cost fuel and other kinds of fuel

Adopting better technologies depends on how people get around. For example, electric vehicles (EVs) leave a much smaller carbon footprint than gasoline or diesel cars, especially in places where energy comes from cleaner sources. Companies are developing sustainable aircraft fuels (SAFs) for airplanes in an effort to reduce pollution. For example, California formed a consortium whose goal is to increase the supply of SAFs to 200 million gallons by 2035. This capacity will allow the state to meet the needs of about 40% of all interstate trips. Hydrogen, ammonia, and biofuels are being looked into by the maritime shipping business as cleaner fuels.


Much of the world's pollution comes from transportation. For example, cars, planes, and ships all release a lot of gases that cause the greenhouse effect. Getting rid of the pollution caused by transportation can be done in several ways. These include using better technologies, creating fuels that last, and making rules that encourage all types of transportation to use less energy and produce fewer emissions.