Ozone loss and detailed investigations on the chemistry in the core of FrIAC’s (Frozen In Anticyclones) events occurring in 2007 and 2011
Abstract
During springtime, after the final stratospheric warming, the breakdown of the polar vortex occurs and the summer circulation starts to develop. Air mass intrusions from the tropics can be trapped into the polar latitudes in an
anticyclone which can persist until August, advected by summer easterlies. These structures, named “Frozen In Anticyclones” (FrIACs), have already been observed in 2003, 2005 and 2007 by MIPAS-ENVISAT and MLS-AURA
instruments [Lahoz et al., 2007, Manney et al., 2006, Thiéblemont et al., 2011]. These FrIACs lead to an irreversible ozone loss in the tropics.
Here, we present a new case of FrIAC occurring in 2011. It is the major one in term of spatial extent since 1960 (see poster #6072). Using MIPAS, MLS tracer species and ozone measurements, we characterize in detail its duration
and location in comparison with the previous FrIAC event in 2007. We compared simulations using several CTM models, and evaluated them against measurements. Then we examined the specific chemistry in the core of the
FrIAC.
Origin : Files produced by the author(s)