Seminar
SPEAKER: David Fahey, NOAA ESRL CSD
TIME: Thursday, May 7, 2009, 3:30 p.m.
PLACE: DSRC (NOAA Building) Room 2A-305, 325 Broadway, Boulder
DIRECTIONS: See http://esrl.noaa.gov/csd/seminars/
TITLE: Aviation and global climate change in the 21st century: Should you stop flying?
ABSTRACT:
Aviation emissions contribute to the radiative forcing (RF) of climate. Of importance are emissions of carbon dioxide (CO2), nitrogen oxides (NOx), aerosols and their precursors (soot and sulphate), and increased cloudiness in the form of persistent linear contrails and induced-cirrus cloudiness. Aviation has grown strongly over the past years, despite world-changing events in the early 2000s, resulting in an increase of passenger traffic of 38%. Presented here are updated values of aviation RF for 2005 based upon new operations data, and updated projections of aviation RF for 2050. The lack of physical process models and adequate observational data for aviation-induced cirrus effects limit confidence in quantifying their RF contribution. An examination of a range of future technological options shows that substantive reductions in aviation fuel usage are possible only with the introduction of radical technologies. Carbon calculators are in use to estimate climate contributions from various human activities. Aviation carbon calculators are of special interest because of aviation's intense use of fossil fuel. However, all are incomplete or incorrect in accounting for short-lived climate forcings because of the lack of a suitable metric for aviation climate effects.