New Research Confirms Dehydration Effects From Aircraft Contrails

Abstract. The uptake of water by contrails in ice-supersaturated air and the release of water after ice particle advection and sedimentation dehydrates the atmosphere at flight levels and redistributes humidity mainly to lower levels. The dehydration is investigated by coupling a plume-scale contrail model with a global aerosol–climate model. The contrail model simulates all the individual contrails forming from global air traffic for meteorological conditions as defined by the climate model. The computed contrail cirrus properties compare reasonably with theoretical concepts and observations. The mass of water in aged contrails may exceed 106 times the mass of water emitted from aircraft. Many of the ice particles sediment and release water in the troposphere, on average 700 m below the mean flight levels. Simulations with and without coupling are compared. The drying at contrail levels causes thinner and longer-lived contrails with about 15 % reduced contrail radiative forcing (RF). The reduced RF from contrails is on the order of 0.06 W m−2, slightly larger than estimated earlier because of higher soot emissions. For normal traffic, the RF from dehydration is small compared to interannual variability. A case with emissions increased by 100 times is used to overcome statistical uncertainty. The contrails impact the entire hydrological cycle in the atmosphere by reducing the total water column and the cover by high- and low-level clouds. For normal traffic, the dehydration changes contrail RF by positive shortwave and negative longwave contributions on the order of 0.04 W m−2, with a small negative net RF. The total net RF from contrails and dehydration remains within the range of previous estimates.

Citation: Schumann, U., Penner, J. E., Chen, Yibin, Zhou, Cheng, and Graf, K.: Dehydration effects from contrails in a coupled contrail–climate model, Atmos. Chem. Phys., 15, 11179-11199, doi:10.5194/acp-15-11179-2015, 2015.
(Source) Atmos. Chem. Phys., 15, 11179-11199, 2015
http://www.atmos-chem-phys.net/15/11179/2015/
doi:10.5194/acp-15-11179-2015
© Author(s) 2015. This work is distributed
under the Creative Commons Attribution 3.0 License.

Volume 15, issue 19 – Research article – 08 Oct 2015

Dehydration effects from contrails in a coupled contrail–climate model

Complete Study (PDF)

U. Schumann1, J. E. Penner2, Yibin Chen2, Cheng Zhou2, and K. Graf1
1Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
2University of Michigan, Department of Atmospheric, Oceanic, and Space Sciences, Ann Arbor, Michigan, USAReceived: 20 Jun 2015 – Published in Atmos. Chem. Phys. Discuss.: 17 Jul 2015
Revised: 16 Sep 2015 – Accepted: 23 Sep 2015 – Published: 08 Oct 2015

New Research Confirms Dehydration Effects From Aircraft Contrails

New Research Confirms Dehydration Effects From Aircraft Contrails

 

 

 

 

 

 

 

 

 
FAIR USE NOTICE. Many of the stories on this site contain copyrighted material whose use has not been specifically authorized by the copyright owner. We are making this material available in an effort to advance the understanding of environmental issues, human rights, economic and political democracy, and issues of social justice. We believe this constitutes a ‘fair use’ of the copyrighted material as provided for in Section 107 of the US Copyright Law which contains a list of the various purposes for which the reproduction of a particular work may be considered fair, such as criticism, comment, news reporting, teaching, scholarship, and research. If you wish to use such copyrighted material for purposes of your own that go beyond ‘fair use’…you must obtain permission from the copyright owner.

The information on this site is provided for educational and entertainment purposes only. It is not intended as a substitute for professional advice of any kind. AirCrap.org assumes no responsibility for the use or misuse of this material.

One thought on “New Research Confirms Dehydration Effects From Aircraft Contrails

  1. Sooooo, what does this mean to humans who absorb this air crap? Are we more susceptible to be more dehydrated ourselves? Do we need to wear long-sleeved clothing for now on? What??????

Comments are closed.