signature=6533feb2e7cb193e268b6b7b37509ef5,Variability and evolution of mid-latitude stratospheric a...

摘要：

The article presents new high-quality continuous stratospheric aerosol observations spanning 1994–2015 at the French Observatoire de Haute-Provence (OHP, 44° N, 6° E) obtained by two independent regularly-maintained lidar systems. Lidar series are compared with global-coverage observations by Stratospheric Aerosol and Gas Experiment (SAGE II), Global Ozone Monitoring by Occultation of Stars (GOMOS), Optical Spectrograph and InfraRed Imaging System (OSIRIS), Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) and Ozone Mapping Profiling Suite (OMPS) satellite instruments, altogether covering the time span of OHP lidar measurements. Local OHP and zonal-mean satellite series of stratospheric aerosol optical depth are in excellent agreement, allowing for accurate characterization of stratospheric aerosol evolution and variability at Northern mid-latitudes during the post-Pinatubo era. The combination of local and global observations is used for careful separation between volcanically-perturbed and quiescent periods. While the volcanic signatures dominate the stratospheric aerosol record, the background aerosol abundance is found to be modulated remotely by poleward transport of convectively-cleansed air from the deep tropics and aerosol-laden air from the Asian monsoon region. The annual cycle of background aerosol at mid-latitudes, featuring a minimum during late spring and a maximum during late summer, correlates with that of water vapour from Microwave Limb Sounder (MLS). Observations covering two volcanically-quiescent periods over the last two decades provide indication of a growth in the non-volcanic component of stratospheric aerosol. A statistically-significant factor of two increase of non-volcanic aerosol since 1998, seasonally restricted to late-summer and fall, is associated with the influence of the Asian monsoon and growing pollution therein.

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