Séminaire
The Cheju ABC Plume-Asian Monsoon Experiment (CAPMEX) was conducted during August-September of 2008 off the Coast of Cheju (Jeju) Island in Korea to take advantage of the unique event associated with unprecedented air pollution mitigation actions during the 2008 Beijing summer Olympics. We collected ground-level and high-elevation unmanned aircraft data before, during, and after the Beijing reductions to infer the black carbon (BC) radiative forcing of pollution plumes from Beijing and other Chinese megacities. The unmanned aerial vehicle (UAV) measurement component of this campaign took place during August 9 to September 30, 2008. The UAV payload was mission-specific and was outfitted to perform a particular set of measurements. These measurements include aerosol concentration, aerosol size distribution, aerosol absorption, cloud drop size distribution, solar radiation fluxes (visible and broadband), and spectral radiative fluxes.
Throughout the CAPMEX, we captured both heavy and light pollution events and witnessed air masses from both pristine oceanic sources and major cities including Beijing and Shanghai. During this period, long-range transported aerosols and black carbon from Beijing, Shanghai and Marine regions were sampled in aerosol layers up to 3-4 km above sea level. The flights during the Beijing- plume period clearly show the elevated levels of BC concentrations in the mixed layer as well as above the mixed layer, and corresponding trends observed in the total particle concentration and the particle size distributions. The diurnal mean solar heating rate, calculated from the observed solar fluxes in shortwave regime (0.3 ~ 2.8 um), at 3 ~ 4 km altitudes for Beijing and marine plume conditions were about 1.0 and 0.75 K/day, respectively. This suggests that an increase of BC concentrations above the boundary layer in the polluted Beijing plume contributed about 30% of atmospheric heating.
Jean-Christophe RAUT
LATMOS / IPSL
Université Paris 6 (UPMC)
Tour 45-46, 3e étage
4, Place Jussieu 75252 Paris Cedex 5
Phone : +33 (0)1 44 27 53 62
Fax : +33 (0)1 44 27 37 76