THREE DIMENSIONAL SIMULATION OF HYDROGEN CHLORIDE AND HYDROGEN FLUORIDE DURING THE AIRBORNE ARCTIC STRATOSPHERiC EXPEDITION
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چکیده
Simulations of the evolution of stratospheric distributions of hydrogen chloride (HC1) and hydrogen fluoride (HF) have been carried out for the period of the Airborne Arctic Stratospheric Expedition (AASE) with at three-dimensional chemistry-transport model. Simulations were performed assuming only homogeneous gas phase &enr. istry for HF and both homogeneous gas phase and heterogeneous chemistry for H C1. Results show heterogeneous loss of H CI is needed to provide agreement with infrared column measurements. Estim•ttes of the impact of heterogeneous loss on the global H C1 distribution are obtained from the model. Reductions of HC1 due to heterogeneous lo s are calculated to be localized to regions of high vorticity, even after more than a month of integration.
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