Abstract

The axial component of atmospheric angular momentum (AAM) reached a decadal minimum during the winter of 1989, when the cool (La Niña) phase of the ENSO cycle and the positive phases of the North Atlantic Oscillation (NAO) and the related Arctic Oscillation (AO) were active. Here, we examine the global atmospheric dynamics associated with this event from the torque point of view. It will be shown how mountain torques on North America, South America and Europe related to these oscillations led to the AAM minimum, partly compensated by a positive ENSO‐related mountain torque over Asia. The friction torque had more nearly equal positive and negative anomalies associated with ENSO and NAO forcing, respectively, and made a smaller, offsetting contribution to the global AAM anomaly during this episode.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.