How does the atmospheric variability drive the aerosol residence time in the Arctic region?

M. Ménégoz (1) , A. Voldoire (2) , H. Teyssèdre (2) , D. Salas y Mélia (2) , V.-H. Peuch (2) , I. Gouttevin (1)

1 LGGE - Laboratoire de glaciologie et géophysique de l'environnement
2 CNRM - Centre national de recherches météorologiques

This paper aims at characterizing the impact of the atmospheric variability on the aerosol burden and residence time in the Arctic region. For this purpose, a global simulation using an emissions inventory from the year 2000 is performed for the period 2000-2005. The model thus describes a 6-year evolution of sulphate, black carbon (BC) and mineral dust, whose variability is driven by the atmosphere only. Our simulation is validated thanks to comparisons with surface observations. The aerosol residence time takes minimum values in fall: 4 days for sulphate and 8 days for BC and dust. It takes maximum values in June: 10 days for sulphate and 16 days for BC and dust. However, from one spring to another, it can vary by about 50% for sulphate, 40% for BC and 100% for dust, depending on the atmospheric variability. In June, sulphate, BC and dust burden averaged over the Arctic region reach respectively maximums of 1.9 mg[S] m-², 0.2 mg m-² and 6 mg m-², characteristic of the so-called "Arctic haze". From one year to another, these values can vary by 20% for sulphate, 10% for BC and 60% for dust.

Mots clés: aerosols; arctic; atmosphere; residence time; pollutant transport

Domaines: Sciences de la Terre

M. Ménégoz, A. Voldoire, H. Teyssèdre, D. Salas y Mélia, V.-H. Peuch, et al.. How does the atmospheric variability drive the aerosol residence time in the Arctic region?. Tellus B - Chemical and Physical Meteorology, 2012, 64, pp.11596. ⟨10.3402/tellusb.v64i0.11596⟩. ⟨insu-00845306⟩