Altitude of atmospheric tracer transport towards Antarctica in present and glacial climate - INSU - Institut national des sciences de l'Univers Accéder directement au contenu
Article Dans Une Revue Quaternary Science Reviews Année : 2010

Altitude of atmospheric tracer transport towards Antarctica in present and glacial climate

Résumé

The preferential altitude of transport of continental tracers towards Antarctica under present and Last Glacial Maximum (21 kyr BP) conditions is analysed using an atmospheric general circulation model with idealized tracers which are emitted at the surface of Australia and South America. It is shown that the difference between the preferential transport altitude of Australian and South American tracers is similar in glacial and interglacial climates. Australian tracers arriving in Antarctica are consistently transported at higher altitudes than tracers emitted in South America. The frequency of low-level transport is stronger at the LGM than at present, reflecting a more vigorous atmospheric circulation at the LGM as a consequence of increased baroclinicity. While the spatial patterns of the total tracer concentrations at the Antarctic surface differ for Australian and South American tracers, with the regions of maximum surface concentration being located to the south-east of the respective tracer sources, the spatial distribution of the part advected via upper atmospheric levels is very similar for the Australian and South American tracers, with a maximum over Queen Maud Land. The simulated changes in transport characteristics cannot explain observed glacial to interglacial variations of dust size spectra which have been interpreted as indicators of the relative intensity of upper and lower level atmospheric dust transport to Antarctica.

Domaines

Glaciologie

Dates et versions

insu-00420834 , version 1 (29-09-2009)

Identifiants

Citer

Gerhard Krinner, Jean-Robert Petit, B. Delmonte. Altitude of atmospheric tracer transport towards Antarctica in present and glacial climate. Quaternary Science Reviews, 2010, 29 (1-2), pp.274-284. ⟨10.1016/j.quascirev.2009.06.020⟩. ⟨insu-00420834⟩
53 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More