Simulation of the global contrail radiative forcing: A sensitivity analysis
Article first published online: 22 DEC 2012
©2012. American Geophysical Union. All Rights Reserved.
Geophysical Research Letters
Volume 39, Issue 24, 28 December 2012
How to Cite
2012), Simulation of the global contrail radiative forcing: A sensitivity analysis, Geophys. Res. Lett., 39, L00F03, doi:10.1029/2012GL054042., , , , and (
- Issue published online: 22 DEC 2012
- Article first published online: 22 DEC 2012
- Manuscript Accepted: 9 NOV 2012
- Manuscript Revised: 6 NOV 2012
- Manuscript Received: 27 SEP 2012
- Federal Aviation Administration . Grant Numbers: DTRT57-10-C-10016, DTRT57-10-X-70020
- radiative forcing
 The contrail radiative forcing induced by human aviation activity is one of the most uncertain contributions to climate forcing. An accurate estimation of global contrail radiative forcing is imperative, and the modeling approach is an effective and prominent method to investigate the sensitivity of contrail forcing to various potential factors. We use a simple offline model framework that is particularly useful for sensitivity studies. The most-up-to-date Community Atmospheric Model version 5 (CAM5) is employed to simulate the atmosphere and cloud conditions during the year 2006. With updated natural cirrus and additional contrail optical property parameterizations, the RRTMG Model (RRTM-GCM application) is used to simulate the global contrail radiative forcing. Global contrail coverage and optical depth derived from the literature for the year 2002 is used. The 2006 global annual averaged contrail net (shortwave + longwave) radiative forcing is estimated to be 11.3 mW m−2. Regional contrail radiative forcing over dense air traffic areas can be more than ten times stronger than the global average. A series of sensitivity tests are implemented and show that contrail particle effective size, contrail layer height, the model cloud overlap assumption, and contrail optical properties are among the most important factors. The difference between the contrail forcing under all and clear skies is also shown.