STOCKHOLM, April 1 (Xinhua) -- A new, national air-travel tax was introduced in Sweden on April 1, with plane journeys departing from Swedish airports to be taxed according to the length of the flights, reported Swedish Television on Sunday.

The tax will be 60 SEK (7 U.S. dollars) on domestic flights and on flights within Europe. Flights to destinations outside of Europe will be taxed 250 SEK, unless the journey is longer than 6,000 kilometers in which case the tax rate is 400 SEK.

It is uncertain whether passengers traveling from Sweden will see rising air fares since the airlines are responsible for paying in the taxes and can decide themselves if they want to add the fees on to the ticket prices or not.

Sweden has some of the cheapest airfares in the world, according to a 2016 survey from the website Kiwi.com, which publishes an aviation price index. Sweden ranks number 10 on that index. At the same time, statistics show that Swedes fly more and more and that emissions from air travel are increasing.

A report from the Chalmers University of Technology in Gothenburg shows that, among Swedes, the number of international flights increased by 30 percent between 1990 and 2014. In 2014, the total emissions from these flights, taking into account the high altitude effect, equaled the total amount of emissions from all private car journeys in Sweden in the same year, the Chalmers report showed.

In October last year, the City of Stockholm published a report on the climate impact of Stockholmers' air travel. A summary included in that report showed that the number of departures from Swedish airports increased by 40 percent between 2009 and 2016. International flights stood for 65 percent of those plane journeys. (1 U.S. dollar = 7.20 SEK)