Observation and simulation of wave breaking in the southern hemispheric stratosphere during VORCORE
An interesting occurrence of a Rossby wave breaking event observed during the VORCORE experiment is presented and explained. Twenty-seven balloons were launched inside the Antarctic polar vortex. Almost all of these balloons evolved in the stratosphere around 500K within the vortex, except the on...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2013-04-01
|
| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/31/675/2013/angeo-31-675-2013.pdf |
| _version_ | 1828254470008471552 |
|---|---|
| author | M. Moustaoui H. Teitelbaum A. Mahalov |
| author_facet | M. Moustaoui H. Teitelbaum A. Mahalov |
| author_sort | M. Moustaoui |
| collection | DOAJ |
| description | An interesting occurrence of a Rossby wave breaking event observed during the
VORCORE experiment is presented and explained. Twenty-seven balloons were
launched inside the Antarctic polar vortex. Almost all of these balloons
evolved in the stratosphere around 500K within the vortex, except the one
launched on 28 October 2005. In this case, the balloon was caught within a
tongue of high potential vorticity (PV), and was ejected from the polar
vortex. The evolution of this event is studied for the period between 19 and
25 November 2005. It is found that at the beginning of this period, the polar
vortex experienced distortions due to the presence of Rossby waves. Then,
these waves break and a tongue of high PV develops. On 25 November, the
tongue became separated from the vortex and the balloon was ejected into the
surf zone. Lagrangian simulations demonstrate that the air masses surrounding
the balloon after its ejection were originating from the vortex edge. The
wave breaking and the development of the tongue are confined within a region
where a planetary Quasi-Stationary Wave 1 (QSW1) induces wind speeds with
weaker values. The QSW1 causes asymmetry in the wind speed and the horizontal
PV gradient along the edge of the polar vortex, resulting in a localized jet.
Rossby waves with smaller scales propagating on top of this jet amplify as
they enter the jet exit region and then break. The role of the QSW1 on the
formation of the weak flow conditions that caused the non-linear wave
breaking observed near the vortex edge is confirmed by three-dimensional
numerical simulations using forcing with and without the contribution of the
QSW1. |
| first_indexed | 2024-04-13T01:59:14Z |
| format | Article |
| id | doaj.art-43974461e40349adb605d9d3f76f5c67 |
| institution | Directory Open Access Journal |
| issn | 0992-7689 1432-0576 |
| language | English |
| last_indexed | 2024-04-13T01:59:14Z |
| publishDate | 2013-04-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Annales Geophysicae |
| spelling | doaj.art-43974461e40349adb605d9d3f76f5c672022-12-22T03:07:41ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05762013-04-013167568710.5194/angeo-31-675-2013Observation and simulation of wave breaking in the southern hemispheric stratosphere during VORCOREM. Moustaoui0H. Teitelbaum1A. Mahalov2School of Mathematical and Statistical Sciences, Arizona State University, Tempe, Arizona, USALaboratoire de Meteorologie Dynamique Ecole Normale Superieure, Paris, FranceSchool of Mathematical and Statistical Sciences, Arizona State University, Tempe, Arizona, USAAn interesting occurrence of a Rossby wave breaking event observed during the VORCORE experiment is presented and explained. Twenty-seven balloons were launched inside the Antarctic polar vortex. Almost all of these balloons evolved in the stratosphere around 500K within the vortex, except the one launched on 28 October 2005. In this case, the balloon was caught within a tongue of high potential vorticity (PV), and was ejected from the polar vortex. The evolution of this event is studied for the period between 19 and 25 November 2005. It is found that at the beginning of this period, the polar vortex experienced distortions due to the presence of Rossby waves. Then, these waves break and a tongue of high PV develops. On 25 November, the tongue became separated from the vortex and the balloon was ejected into the surf zone. Lagrangian simulations demonstrate that the air masses surrounding the balloon after its ejection were originating from the vortex edge. The wave breaking and the development of the tongue are confined within a region where a planetary Quasi-Stationary Wave 1 (QSW1) induces wind speeds with weaker values. The QSW1 causes asymmetry in the wind speed and the horizontal PV gradient along the edge of the polar vortex, resulting in a localized jet. Rossby waves with smaller scales propagating on top of this jet amplify as they enter the jet exit region and then break. The role of the QSW1 on the formation of the weak flow conditions that caused the non-linear wave breaking observed near the vortex edge is confirmed by three-dimensional numerical simulations using forcing with and without the contribution of the QSW1.https://www.ann-geophys.net/31/675/2013/angeo-31-675-2013.pdf |
| spellingShingle | M. Moustaoui H. Teitelbaum A. Mahalov Observation and simulation of wave breaking in the southern hemispheric stratosphere during VORCORE Annales Geophysicae |
| title | Observation and simulation of wave breaking in the southern hemispheric stratosphere during VORCORE |
| title_full | Observation and simulation of wave breaking in the southern hemispheric stratosphere during VORCORE |
| title_fullStr | Observation and simulation of wave breaking in the southern hemispheric stratosphere during VORCORE |
| title_full_unstemmed | Observation and simulation of wave breaking in the southern hemispheric stratosphere during VORCORE |
| title_short | Observation and simulation of wave breaking in the southern hemispheric stratosphere during VORCORE |
| title_sort | observation and simulation of wave breaking in the southern hemispheric stratosphere during vorcore |
| url | https://www.ann-geophys.net/31/675/2013/angeo-31-675-2013.pdf |
| work_keys_str_mv | AT mmoustaoui observationandsimulationofwavebreakinginthesouthernhemisphericstratosphereduringvorcore AT hteitelbaum observationandsimulationofwavebreakinginthesouthernhemisphericstratosphereduringvorcore AT amahalov observationandsimulationofwavebreakinginthesouthernhemisphericstratosphereduringvorcore |