Related Experiment Video
Updated: Mar 19, 2026

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data
Published on: December 9, 2015
Role of quasiresonant planetary wave dynamics in recent boreal spring-to-autumn extreme events
Vladimir Petoukhov1, Stefan Petri2, Stefan Rahmstorf2
1Potsdam Institute for Climate Impact Research, D-14412 Potsdam, Germany; john@pik-potsdam.de petukhov@pik-potsdam.de.
Abstract:
In boreal spring-to-autumn (May-to-September) 2012 and 2013, the Northern Hemisphere (NH) has experienced a large number of severe midlatitude regional weather extremes. Here we show that a considerable part of these extremes were accompanied by highly magnified quasistationary midlatitude planetary waves with zonal wave numbers m = 6, 7, and 8. We further show that resonance conditions for these planetary waves were, in many cases, present before the onset of high-amplitude wave events, with a lead time up to 2 wk, suggesting that quasiresonant amplification (QRA) of these waves had occurred. Our results support earlier findings of an important role of the QRA mechanism in amplifying planetary waves, favoring recent NH weather extremes.
Related Concept Videos
Frequency of Spring-Mass System
Consider a block on a spring on a frictionless surface. There...
Sound Waves: Resonance
Precipitation Processes
Forced Oscillations
Concept of Resonance and its Characteristics
Standing Waves

