This title appears in the Scientific Report :
2023
Estimation of the QBO wave driving based on satellite observations and reanalyses
Estimation of the QBO wave driving based on satellite observations and reanalyses
limate models have difficulties to simulate a realistic quasi-biennial oscillation (QBO) of the zonal wind in the tropical stratosphere and its response to a changing climate. One of the main reasons are uncertainties in the wave driving by small scale gravity waves and global-scale equatorial wave...
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Personal Name(s): | Ern, Manfred (Corresponding author) |
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Contributing Institute: |
Stratosphäre; IEK-7 |
Imprint: |
2023
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Conference: | QBO Workshop, Oxford (UK), 2023-03-27 - 2023-03-31 |
Document Type: |
Poster |
Research Program: |
Climate Feedbacks |
Publikationsportal JuSER |
limate models have difficulties to simulate a realistic quasi-biennial oscillation (QBO) of the zonal wind in the tropical stratosphere and its response to a changing climate. One of the main reasons are uncertainties in the wave driving by small scale gravity waves and global-scale equatorial wave modes. Therefore estimates of the wave driving from global observations and from reanalyses are needed as a guidance for further improvement. In our work, we discuss how estimates of the QBO driving by global-scale Kelvin waves can be derived from temperature observations of SABER infrared limb-sounding satellite data. These estimates are compared with estimates from three modern reanalyses (ERA-5, JRA-55, and MERRA-2), and qualitatively good agreement is found. The expected gravity wave driving of the QBO is estimated from the reanalyses by evaluating the residual term in the Transformed Eulerian Mean (TEM) zonal momentum budget. These estimates are compared with absolute values of the gravity wave driving of the QBO derived from SABER infrared limb soundings. Even though the estimates from the satellite data are subject to large errors, qualitatively, we find reasonable agreement with estimates from the reanalyses. This supports the use of reanalyses as a reference for free-running climate models. |