24 March 2014

Environmental Science and Technology best policy paper of 2013

A comparison of the climate impacts of different modes of travel has been named the best policy paper of 2013 by the editors of the journal Environmental Science & Technology (ES&T). The study, conducted by MAG researcher Jens Borken-Kleefeld and colleagues from CICERO - Center for International Climate and Environmental Research - Oslo, was selected from all the policy-related, peer-reviewed papers published in ES&T last year.

EST 2013 - Mode, load and specific climate impact from passenger trips

EST 2013 - Mode, load and specific climate impact from passenger trips

Mode, Load, And Specific Climate Impact from Passenger Trips

Jens Borken-Kleefeld, Jan Fuglestvedt and Terje Berntsen

Environ. Sci. Technol., 2013, 47 (14), pp 7608–7614.
DOI: 10.1021/es4003718

The climate impact from a long-distance trip can easily vary by a factor of 10 per passenger depending on mode choice, vehicle efficiency and occupancy. The specific climate impact of long-distance car travel is compared with that from coach, train or air trips, accounting for emissions of both CO2 and short-lived climate pollutants. This particularly affects the ranking of aircraft’s climate impact relative to other modes. The specific impact is assessed for both the Global Warming Potential and the Global Temperature Change Potential, considering time horizons between 20 and 100 years, and comparing with results accounting only for CO2 emissions. A car’s fuel efficiency and occupancy are central determinants of whether the impact from a trip is as high as from air travel or as low as from train travel. These results can be used for carbon-offsetting schemes, mode choice and transportation planning for climate mitigation.

Further discussion of the study's findings may be heard in an interview with Terje Berntsen, corresponding author of the paper.

An article commenting on ES&T’s Best Papers of 2013 by the journal's editor-in-chief explains the process undertaken to select the top papers in four categories from the 1730 articles published by ES&T in 2013.

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Last edited: 21 September 2014


Jens Borken-Kleefeld

Senior Research Scholar

Air Quality and Greenhouse Gases

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International Institute for Applied Systems Analysis (IIASA)
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