Effects of missing gravity waves on stratospheric dynamics; part 1: climatology

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F20%3A10421920" target="_blank" >RIV/00216208:11320/20:10421920 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=5Xux-_IRE7" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=5Xux-_IRE7</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s00382-020-05166-w" target="_blank" >10.1007/s00382-020-05166-w</a>

Result language

angličtina

Original language name

Effects of missing gravity waves on stratospheric dynamics; part 1: climatology

Original language description

Energy and momentum deposition from planetary-scale Rossby waves as well as from small-scale gravity waves (GWs) largely control stratospheric dynamics. Interactions between these different wave types, however, complicate the quantification of their individual contribution to the overall dynamical state of the middle atmosphere. In state-of-the-art general circulation models (GCMs), the majority of the GW spectrum cannot be resolved and therefore has to be parameterised. This is commonly implemented in two discrete schemes, one for GWs that originate from flow over orographic obstacles and one for all other kinds of GWs (non-orographic GWs). In this study, we attempt to gain a deeper understanding of the interactions of resolved with parameterised wave driving and of their influence on the stratospheric zonal winds and on the Brewer-Dobson circulation (BDC). For this, we set up a GCM time slice experiment with two sensitivity simulations: one without orographic GWs and one without non-orographic GWs. Our findings include an acceleration of the polar vortices, which has historically been one of the main reasons for including explicit GW parameterisations in GCMs. Further, we find inter-hemispheric differences in BDC changes when omitting GWs that can be explained by wave compensation and amplification effects. These are partly evoked through local changes in the refractive properties of the atmosphere caused by the omitted GW drag and a thereby increased planetary wave propagation. However, non-local effects on the flow can act to suppress vertical wave fluxes into the stratosphere for a very strong polar vortex. Moreover, we study mean age of stratospheric air to investigate the impact of missing GWs on tracer transport. On the basis of this analysis, we suggest that the larger ratio of planetary waves to GWs leads to enhanced horizontal mixing, which can have a large impact on stratospheric tracer distributions.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10509 - Meteorology and atmospheric sciences

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2020

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Climate Dynamics

ISSN

0930-7575

e-ISSN

—

Volume of the periodical

54

Issue of the periodical within the volume

5-6

Country of publishing house

US - UNITED STATES

Number of pages

19

Pages from-to

3165-3183

UT code for WoS article

000516155200001

EID of the result in the Scopus database

2-s2.0-85079723683