Teleconnections of the Quasi-Biennial Oscillation in a multi-model ensemble of QBO-resolving models

• Published in: Quarterly Journal of the Royal Meteorological Society
• Main Authors: Anstey, James A., Simpson, Isla R., Richter, Jadwiga H., Naoe, Hiroaki, Taguchi, Masakazu, Bellprat, Omar
• Other Authors: Barcelona Supercomputing Center
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2021
• Subjects: Àrees temàtiques de la UPC::Enginyeria agroalimentària::Ciències de la terra i de la vida::Climatologia i meteorologia; Stratospheric circulation; Teleconnections (Climatology); North Atlantic oscillation; Atmospheric circulation > Mathematical models; Polar vortex; Quasi-Biennial Oscillation; Seasonal forecasting; Stratosphere; Stratosphere–troposphere coupling; Teleconnection; Estratosfera; North Atlantic
• Online Access: http://hdl.handle.net/2117/350224; https://doi.org/10.1002/qj.4048

The Quasi-biennial Oscillation (QBO) dominates the interannual variability of the tropical stratosphere and influences other regions of the atmosphere. The high predictability of the QBO implies that its teleconnections could lead to increased skill of seasonal and decadal forecasts provided the relevant mechanisms are accurately represented in models. Here modelling and sampling uncertainties of QBO teleconnections are examined using a multi-model ensemble of QBO-resolving atmospheric general circulation models that have carried out a set of coordinated experiments as part of the Stratosphere-troposphere Processes And their Role in Climate (SPARC) QBO initiative (QBOi). During Northern Hemisphere winter, the stratospheric polar vortex in most of these models strengthens when the QBO near 50 hPa is westerly and weakens when it is easterly, consistent with, but weaker than, the observed response. These weak responses are likely due to model errors, such as systematically weak QBO amplitudes near 50 hPa, affecting the teleconnection. The teleconnection to the North Atlantic Oscillation is less well captured overall, but of similar strength to the observed signal in the few models that do show it. The models do not show clear evidence of a QBO teleconnection to the Northern Hemisphere Pacific-sector subtropical jet. We acknowledge the UK's Centre for Environmental Data Analysis (CEDA) for hosting the QBOi data archive. This work was supported by the National Center for Atmospheric Research, which is a major facility sponsored by the National Science Foundation under Cooperative Agreement no. 1852977. Portions of this study were supported by the Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling Program of the U.S. Department of Energy's Office of Biological & Environmental Research (BER) via National Science Foundation IA 1844590. NB was supported by the Met Office Hadley Centre Programme funded by BEIS and Defra. SO and LG were supported by the National Centre ...