Gravity waves in the winter stratosphere over the Southern Ocean: high-resolution satellite observations and 3-D spectral analysis
Atmospheric gravity waves play a key role in the transfer of energy and momentum between layers of the Earth's atmosphere. However, nearly all general circulation models (GCMs) seriously under-represent the momentum fluxes of gravity waves at latitudes near 60∘ S, which can lead to significant...
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ftfzjuelichnvdb:oai:juser.fz-juelich.de:868088 2023-05-15T14:02:57+02:00 Gravity waves in the winter stratosphere over the Southern Ocean: high-resolution satellite observations and 3-D spectral analysis Hindley, Neil P. Wright, Corwin J. Smith, Nathan D. Hoffmann, Lars Holt, Laura A. Alexander, M. Joan Moffat-Griffin, Tracy Mitchell, Nicholas J. DE 2019 https://juser.fz-juelich.de/record/868088 https://juser.fz-juelich.de/search?p=id:%22FZJ-2019-06679%22 eng eng EGU info:eu-repo/semantics/altIdentifier/wos/WOS:000503444400003 info:eu-repo/semantics/altIdentifier/hdl/2128/23716 info:eu-repo/semantics/altIdentifier/issn/1680-7316 info:eu-repo/semantics/altIdentifier/issn/1680-7324 info:eu-repo/semantics/altIdentifier/doi/10.5194/acp-19-15377-2019 https://juser.fz-juelich.de/record/868088 https://juser.fz-juelich.de/search?p=id:%22FZJ-2019-06679%22 info:eu-repo/semantics/openAccess Atmospheric chemistry and physics 19(24), 15377 - 15414 (2019). doi:10.5194/acp-19-15377-2019 info:eu-repo/classification/ddc/550 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2019 ftfzjuelichnvdb https://doi.org/10.5194/acp-19-15377-2019 2022-07-14T11:19:29Z Atmospheric gravity waves play a key role in the transfer of energy and momentum between layers of the Earth's atmosphere. However, nearly all general circulation models (GCMs) seriously under-represent the momentum fluxes of gravity waves at latitudes near 60∘ S, which can lead to significant biases. A prominent example of this is the “cold pole problem”, where modelled winter stratospheres are unrealistically cold. There is thus a need for large-scale measurements of gravity wave fluxes near 60∘ S, and indeed globally, to test and constrain GCMs. Such measurements are notoriously difficult, because they require 3-D observations of wave properties if the fluxes are to be estimated without using significant limiting assumptions. Here we use 3-D satellite measurements of stratospheric gravity waves from NASA's Atmospheric Infrared Sounder (AIRS) Aqua instrument. We present the first extended application of a 3-D Stockwell transform (3DST) method to determine localised gravity wave amplitudes, wavelengths and directions of propagation around the entire region of the Southern Ocean near 60∘ S during austral winter 2010. We first validate our method using a synthetic wavefield and two case studies of real gravity waves over the southern Andes and the island of South Georgia. A new technique to overcome wave amplitude attenuation problems in previous methods is also presented. We then characterise large-scale gravity wave occurrence frequencies, directional momentum fluxes and short-timescale intermittency over the entire Southern Ocean. Our results show that highest wave occurrence frequencies, amplitudes and momentum fluxes are observed in the stratosphere over the mountains of the southern Andes and Antarctic Peninsula. However, we find that around 60 %–80 % of total zonal-mean momentum flux is located over the open Southern Ocean during June–August, where a large “belt” of increased wave occurrence frequencies, amplitudes and fluxes is observed. Our results also suggest significant short-timescale variability of ... Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Southern Ocean Forschungszentrum Jülich: JuSER (Juelich Shared Electronic Resources) Antarctic Southern Ocean Antarctic Peninsula Austral Atmospheric Chemistry and Physics 19 24 15377 15414 |
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Forschungszentrum Jülich: JuSER (Juelich Shared Electronic Resources) |
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language |
English |
topic |
info:eu-repo/classification/ddc/550 |
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info:eu-repo/classification/ddc/550 Hindley, Neil P. Wright, Corwin J. Smith, Nathan D. Hoffmann, Lars Holt, Laura A. Alexander, M. Joan Moffat-Griffin, Tracy Mitchell, Nicholas J. Gravity waves in the winter stratosphere over the Southern Ocean: high-resolution satellite observations and 3-D spectral analysis |
topic_facet |
info:eu-repo/classification/ddc/550 |
description |
Atmospheric gravity waves play a key role in the transfer of energy and momentum between layers of the Earth's atmosphere. However, nearly all general circulation models (GCMs) seriously under-represent the momentum fluxes of gravity waves at latitudes near 60∘ S, which can lead to significant biases. A prominent example of this is the “cold pole problem”, where modelled winter stratospheres are unrealistically cold. There is thus a need for large-scale measurements of gravity wave fluxes near 60∘ S, and indeed globally, to test and constrain GCMs. Such measurements are notoriously difficult, because they require 3-D observations of wave properties if the fluxes are to be estimated without using significant limiting assumptions. Here we use 3-D satellite measurements of stratospheric gravity waves from NASA's Atmospheric Infrared Sounder (AIRS) Aqua instrument. We present the first extended application of a 3-D Stockwell transform (3DST) method to determine localised gravity wave amplitudes, wavelengths and directions of propagation around the entire region of the Southern Ocean near 60∘ S during austral winter 2010. We first validate our method using a synthetic wavefield and two case studies of real gravity waves over the southern Andes and the island of South Georgia. A new technique to overcome wave amplitude attenuation problems in previous methods is also presented. We then characterise large-scale gravity wave occurrence frequencies, directional momentum fluxes and short-timescale intermittency over the entire Southern Ocean. Our results show that highest wave occurrence frequencies, amplitudes and momentum fluxes are observed in the stratosphere over the mountains of the southern Andes and Antarctic Peninsula. However, we find that around 60 %–80 % of total zonal-mean momentum flux is located over the open Southern Ocean during June–August, where a large “belt” of increased wave occurrence frequencies, amplitudes and fluxes is observed. Our results also suggest significant short-timescale variability of ... |
format |
Article in Journal/Newspaper |
author |
Hindley, Neil P. Wright, Corwin J. Smith, Nathan D. Hoffmann, Lars Holt, Laura A. Alexander, M. Joan Moffat-Griffin, Tracy Mitchell, Nicholas J. |
author_facet |
Hindley, Neil P. Wright, Corwin J. Smith, Nathan D. Hoffmann, Lars Holt, Laura A. Alexander, M. Joan Moffat-Griffin, Tracy Mitchell, Nicholas J. |
author_sort |
Hindley, Neil P. |
title |
Gravity waves in the winter stratosphere over the Southern Ocean: high-resolution satellite observations and 3-D spectral analysis |
title_short |
Gravity waves in the winter stratosphere over the Southern Ocean: high-resolution satellite observations and 3-D spectral analysis |
title_full |
Gravity waves in the winter stratosphere over the Southern Ocean: high-resolution satellite observations and 3-D spectral analysis |
title_fullStr |
Gravity waves in the winter stratosphere over the Southern Ocean: high-resolution satellite observations and 3-D spectral analysis |
title_full_unstemmed |
Gravity waves in the winter stratosphere over the Southern Ocean: high-resolution satellite observations and 3-D spectral analysis |
title_sort |
gravity waves in the winter stratosphere over the southern ocean: high-resolution satellite observations and 3-d spectral analysis |
publisher |
EGU |
publishDate |
2019 |
url |
https://juser.fz-juelich.de/record/868088 https://juser.fz-juelich.de/search?p=id:%22FZJ-2019-06679%22 |
op_coverage |
DE |
geographic |
Antarctic Southern Ocean Antarctic Peninsula Austral |
geographic_facet |
Antarctic Southern Ocean Antarctic Peninsula Austral |
genre |
Antarc* Antarctic Antarctic Peninsula Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Southern Ocean |
op_source |
Atmospheric chemistry and physics 19(24), 15377 - 15414 (2019). doi:10.5194/acp-19-15377-2019 |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000503444400003 info:eu-repo/semantics/altIdentifier/hdl/2128/23716 info:eu-repo/semantics/altIdentifier/issn/1680-7316 info:eu-repo/semantics/altIdentifier/issn/1680-7324 info:eu-repo/semantics/altIdentifier/doi/10.5194/acp-19-15377-2019 https://juser.fz-juelich.de/record/868088 https://juser.fz-juelich.de/search?p=id:%22FZJ-2019-06679%22 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/acp-19-15377-2019 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
19 |
container_issue |
24 |
container_start_page |
15377 |
op_container_end_page |
15414 |
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1766273411651207168 |