naa a22 4500 530201615 20181026074439.0 cr unu---uuuuu 181026s2016 xx s 000 0 eng 1680-7316 10.5194/acp-16-15529-2016 doi 10.5194/acp-16-15529-2016 doi (BORIS)oai:boris.unibe.ch:91617 (ETHRESEARCH)oai:www.research-collection.ethz.ch:20.500.11850/123933 530 ddc 550 ddc 910 ddc Multidecadal variations of the effects of the Quasi-Biennial Oscillation on the climate system [Elektronische Daten] [Stefan Brönnimann, Abdul Malik, Alexander Stickler, Martin Wegmann, Christoph Raible, Stefan Muthers, Julien Anet, Eugene Rozanov, Werner Schmutz] Atmos. chem. phys. publishedVersion openAccess eu-repo Effects of the Quasi-Biennial Oscillation (QBO) on tropospheric climate are not always strong or they appear only intermittently. Studying them requires long time series of both the QBO and climate variables, which has restricted previous studies to the past 30-50 years. Here we use the benefits of an existing QBO reconstruction back to 1908. We first investigate additional, newly digitized historical observations of stratospheric winds to test the reconstruction. Then we use the QBO time series to analyse atmospheric data sets (reconstructions and reanalyses) as well as the results of coupled ocean-atmosphere-chemistry climate model simulations that were forced with the reconstructed QBO. We investigate effects related to (1) tropical-extratropical interaction in the stratosphere, wave-mean flow interaction and subsequent downward propagation, and (2) interaction between deep tropical convection and stratospheric flow. We generally find weak connections, though some are statistically significant over the 100-year period and consistent with model results. Apparent multidecadal variations in the connection between the QBO and the investigated climate responses are consistent with a small effect in the presence of large variability, with one exception: the imprint on the northern polar vortex, which is seen in recent reanalysis data, is not found in the period 1908-1957. Conversely, an imprint in Berlin surface air temperature is only found in 1908-1957 but not in the recent period. Likewise, in the model simulations both links tend to appear alternatingly, suggesting a more systematic modulation due to a shift in the circulation for example. Over the Pacific warm pool, we find increased convection during easterly QBO, mainly in boreal winter in observation-based data as well as in the model simulations, with large variability. No QBO effects were found in the Indian monsoon strength or Atlantic hurricane frequency. Creative Commons Attribution 3.0 Unported http://creativecommons.org/licenses/by/3.0 ethresearch Brönnimann Stefan joint author Malik Abdul joint author Stickler Alexander joint author Wegmann Martin joint author Raible Christoph joint author Muthers Stefan joint author Anet Julien joint author Rozanov Eugene joint author Schmutz Werner joint author Atmospheric chemistry and physics 16(24), pp. 15529-15543 1680-7316 367226995 http://boris.unibe.ch/91617/1/acp-16-15529-2016.pdf text/html WWW-Backlink auf das Repository 1 info:eu-repo/semantics/article boris PeerReviewed boris peerstatus BORIS 856 40 http://boris.unibe.ch/91617/1/acp-16-15529-2016.pdf text/html WWW-Backlink auf das Repository BORIS 700 1- Brönnimann Stefan joint author BORIS 700 1- Malik Abdul joint author BORIS 700 1- Stickler Alexander joint author BORIS 700 1- Wegmann Martin joint author BORIS 700 1- Raible Christoph joint author BORIS 700 1- Muthers Stefan joint author BORIS 700 1- Anet Julien joint author BORIS 700 1- Rozanov Eugene joint author BORIS 700 1- Schmutz Werner joint author BORIS 773 0- Atmospheric chemistry and physics 16(24), pp. 15529-15543 1680-7316 367226995 ETHRESEARCH 856 40 http://hdl.handle.net/20.500.11850/123933 text/html WWW-Backlink auf das Repository (Open access) ETHRESEARCH 700 1- Brönnimann Stefan joint author ETHRESEARCH 700 1- Malik Abdul joint author ETHRESEARCH 700 1- Stickler Alexander joint author ETHRESEARCH 700 1- Wegmann Martin joint author ETHRESEARCH 700 1- Raible Christoph C. joint author ETHRESEARCH 700 1- Muthers Stefan joint author ETHRESEARCH 700 1- Anet Julien; id_orcid 0000-0002-2949-1363 joint author ETHRESEARCH 700 1- Rozanov Eugene joint author ETHRESEARCH 700 1- Schmutz Werner joint author ETHRESEARCH 773 0- Atmospheric Chemistry and Physics Göttingen : Copernicus 16 (24), pp. 15529-15543 1680-7375 BK010053 XK010053 XK010000 BORIS BORIS BORIS info:eu-repo/semantics/article openAccess ETHRESEARCH ETHRESEARCH ETHRESEARCH Journal Article Open access