CERFACS CERFACS Scientific Activity Report Jan. 2010 – Dec. 2011

INTRODUCTION
instead of regular kerosene. The agrofuels are expected to release less soot particles and NOx emissions.
If those assumptions are right the aircraft using agrofuel should have slightly less atmospheric impact, but
uncertainties are large due to very limited data existing on emissions by engines using agrofuels.
In addition, a new project has been initiated to evaluate the atmospheric impact of the solid propellants
used by the Ariane V and VEGA rockets, and by the SOYOUZ rocket that uses kerosene as a propellant.
In the case of rockets using solid propergol a significant fraction of the chlorine from the propellant is
released in form of chlorine radicals and gases, Cl, ClO, Cl 2 , that can locally destroy the atmospheric
ozone. Evaluations of these effects have been performed with a simple chemistry-diffusion model. The
results obtained show a significant ozone destruction regionally above the launch site and are consistent
with observations reported for the US shuttle launches. In the case of Soyouz, preliminary calculations
show that a moderate ozone destruction can be found in the upper stratosphere due to the water vapour
emissions whereas negligible effects are expected in the lower stratosphere. The impact of soot emissions
and the possible formation of ice in the stratosphere remains to be evaluated.
We have developed numerous cooperations within the present research activities. With the CNRM for the
use of Méso-NH and ARPEGE/Climat and MOCAGE models, with the LSCE for implementation of our
plume parameterization, with the ONERA for the near aircraft field simulations, and at the european level
within the SWAFEA project coordinated by ONERA to study the impact of alternate fuel to the kerosene.
Further, the “RTRA Sciences et Technologie pour l’Aéronautique et l’Espace” is supporting the ITAAC
project that is coordinated by CERFACS and IMFT, and includes research teams from the CNRM, the
IMFT, the ISAE, the LAPLACE laboratory and the SAFIRE unit.
The study of the possible impact of rocket launches on the atmospheric ozone content has been supported
by the CNES.
The next sections detail the results obtained within the period covered by this report.
180 Jan. 2010 – Dec. 2011