The role of planetary waves in the tropospheric jet response to stratospheric cooling
Abstract
An idealized general circulation model is used to assess the importance of planetary-scale waves in determining the position of the tropospheric jet, specifically its tendency to shift poleward as winter stratospheric cooling is increased. Full model integrations are compared against integrations in which planetary waves are truncated in the zonal direction, and only synoptic-scale waves are retained. Two series of truncated integrations are considered, using (i) a modified radiative equilibrium temperature or (ii) a nudged-bias correction technique. Both produce tropospheric climatologies that are similar to the full model when stratospheric cooling is weak. When stratospheric cooling is increased, the results indicate that the interaction between planetary- and synoptic-scale waves plays an important role in determining the structure of the tropospheric mean flow and rule out the possibility that the jet shift occurs purely as a response to changes in the planetary- or synoptic-scale wave fields alone.
Citation
Smith , K L & Scott , R K 2016 , ' The role of planetary waves in the tropospheric jet response to stratospheric cooling ' , Geophysical Research Letters , vol. 43 , no. 6 , pp. 2904-2911 . https://doi.org/10.1002/2016GL067849
Publication
Geophysical Research Letters
Status
Peer reviewed
ISSN
1944-8007Type
Journal article
Description
K.L.S. is funded in part by a Natural Sciences and Engineering Council of Canada Postdoctoral Fellowship. R.K.S. acknowledges support from the National Science Foundation.Collections
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