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The impact of cars on environment and climate

Why you should learn about the environment

The whole world is trying to reduce its carbon dioxide emissions. A significant part of those emissions is caused by vehicle traffic. This means that the Riksdag, the government and its agencies have an interest in getting people to be as environmentally friendly as possible.

Environmental objectives in the curriculum for a category B licence

  • Be aware of the environmental requirements set for the vehicles.
  • Learn the correlation between driving style and environmental impact (eco-driving).
  • Understand how your choice to drive (rather than take the train, for example) impacts on the environment.

Greenhouse effect

The greenhouse effect is named after the function of a greenhouse. The rays of the sun come in through the glass ceiling of the greenhouse and give off heat. Most of that heat then remains in the greenhouse, creating a suitable environment for the plants.

The same process occurs naturally at a larger scale as well. In that case, the earth is the plant and the atmosphere is the glass ceiling.

The problem arises when the greenhouse effect is unnaturally enhanced. This is what happens when we extract fossil fuels from the earth and burn them. One of the residues that form is carbon dioxide (the most important greenhouse gas).

The carbon dioxide rises and gets caught in the atmosphere, which makes the “glass ceiling” thicker, making it trap too much heat.

Normal greenhouse effect

Normal greenhouse effect
The rays of the sun (yellow arrows) pass through the atmosphere (grey line) and reach the earth. Much of the heat is absorbed (red dots) and the excess bounces off the earth’s surface and is reflected back out into space (red arrows).

Enhanced greenhouse effect

Enhanced greenhouse effect
The car releases emissions into the atmosphere, which makes it thicker. When the atmosphere gets thicker, some of the heat rays reflected back from the surface cannot get through. These rays instead bounce back towards the earth while emitting more heat. In other words, the earth is getting warmer than it otherwise would.


There are many potential consequences of a warmer climate. Some we can already see today, others we have thankfully not yet experienced.

Examples of climate change consequences

  • Natural disasters – meltwater from giant glaciers can cause great floods.
  • Agricultural disturbances – certain food crops are highly sensitive to temperature shifts, which means that very small changes can make their cultivation impossible.
  • Diseases – we can get diseases spreading to Sweden that currently cannot withstand our cold climate.
  • Water shortage – a large part of the earth’s population uses glacier meltwater as drinking water. If the glaciers melt, these people will have no water to drink.
  • Conflicts & wars – when a country no longer has access to drinkable water, or is struck by natural disaster, the people have to go somewhere else. It is not certain that millions of climate refugees will be welcomed with open arms in other countries, which could lead to war.

Reduce your impact

  • Drive green (eco-driving).
  • Buy a car that is kind on the environment. New cars are usually better than old ones.
  • Use public transportation to a greater extent; it is more environmentally friendly.
  • Wash your car with environmentally friendly detergents and do it at a car wash.
  • Have the right air pressure in your tyres.
  • Take off any unnecessary equipment (such as a roof box).

Theory test with video questions

Video questions – Swedish theory test Free demo – try 65 questions

Last updated 2021-01-22.