Dynamical perspective on the middle atmosphere research in Sweden
description
Transcript of Dynamical perspective on the middle atmosphere research in Sweden
Dynamical perspective on the middle
atmosphere research in Sweden
2010-03-24, SRS-Meeting, Stockholm
Heiner Körnich, [email protected]
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Overview
• The middle atmosphere• Impact direction?• Research areas• Outlook• Summary
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By Mark R. Schoeberl
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Middle atmosphere
Climatesystem +
Troposphere
Dynamical influence goesBottom-up Top-down
Planetary, gravity and tidal wavesLocal instability
“Downward propagation”?4
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Downward propagation of the zonal wind at 60ºNP
ress
ure
(hP
a)
NCEP reanalysis
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50
40
30
20
10
0
-10
-20
m/s
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Downward propagation of the zonal wind at 60ºNP
ress
ure
(hP
a)
NCEP reanalysis
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50
40
30
20
10
0
-10
-20
m/sdrag
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Downward propagation of the zonal wind at 60ºNP
ress
ure
(hP
a)
NCEP reanalysis
60
50
40
30
20
10
0
-10
-20
m/s
drag
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Downward propagation of the zonal wind at 60ºNP
ress
ure
(hP
a)
NCEP reanalysis
60
50
40
30
20
10
0
-10
-20
m/s
drag
By
Mar
k R
. S
choe
berl
Noctilucent clouds are very sensitive
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Photo by Nathan Wilhelm
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Photo by Nathan Wilhelm
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Photo by Nathan Wilhelm
• Sweden, France, Finland, Canada
• launched on February 20, 2001
• 250 kg
• sun-synchronous near-polar orbit at ~600 km altitude
• 2 instruments:
- Sub-mm / mm Radiometer (SMR)
- Optical Spectrograph and InfraRed Imaging System (OSIRIS)
NLC properties observed by Odin
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NLC radii from Odin
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Polar winter stratosphere temperature as planetary
wave activity proxy
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Polar winter stratosphere temperature as planetary
wave activity proxyVS.NLC radii from Odin
Signals are on the opposite side of globe!
After Karlsson et al. (GRL 2007)
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Interhemispheric coupling – The essential modelTemperature response (shaded) and control mean (contours)
-20 -10 -5 -2 -1 1 2 5 10 20
Kör
nich
and
Bec
ker
(AS
R 2
010)
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NLC ∝- ΔT
Interhemispheric coupling – The essential modelTemperature response (shaded) and control mean (contours)
-20 -10 -5 -2 -1 1 2 5 10 20
Kör
nich
and
Bec
ker
(AS
R 2
010)
Planetary waves in winter tropo-stratosphere.
Change in the mean flow
Feedbackbetween
mean flowand
gravity waves
Change in circulation and
NLC
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-20 -10 -5 -2 -1 1 2 5 10 20
Kör
nich
and
Bec
ker
(AS
R 2
010)
No interhemispheric coupling- because no gravity waves in the Summer hemisphere
Planetary waves in winter tropo-stratosphere.
Change in the mean flow
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Northern and southern winter stratosphere as seen by Odin
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(c) Chalmers
Height of the summer mesopauseKirkwood et al. (GRL 2008)
Polar mesosphere summer echos (PMSE) is a proxy for the mesopause height
On southern hemishpere more variable
Southern hemisphere summer mesopause 2007/2008 unusually high
Interhemispheric coupling helps to explain these observations.
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Annual cycle in H2O observed by Odin
Lossow et al. (JGR 2009)
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Annual cycle in H2O observed by Odin
Difference in transport circulation
through interhemispheric coupling
Lossow et al. (JGR 2009)
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By
Mar
k R
. S
choe
berl
Probing the stratospheric transport
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Stratospheric Age of Air
Stratospheric age: time from entry in the tropics to any point
New method: Using water isotopologues observed by Odin combined with a transport model
Sanchez et al. (to be submitted to ACP 2010)
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Descent observed by OdinUrban et al. (ACP 2009), Orsolini et al. (ACP 2009)
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Pot
entia
l tem
pera
ture
Tracer-tracer correlations by OdinKhosrawi et al. (ACP 2009)
Includes both transport and chemistryDiabatic descent in Ozone and N2OImportant benchmark for chemical climate models 28
By
Mar
k R
. S
choe
berl
Mesospheric instability
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Summer mesospheric 2 and 5-day wave
Belova et al. (AG 2008)
30Belova et al. (AG 2008)
Belova et al. (AG 2008)
Local instability
could yieldTop-downinfluence?
Summer mesospheric 2 and 5-day wave
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By Mark R. Schoeberl
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By
Mar
k R
. S
choe
berl
Measuring winds in the stratosphere
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Atmospheric Dynamics Mission
ADM - Aeolus
By Mark R. Schoeberl
PREMIER: Process Exploration through Measurements of Infrared and Millimetre-wave Emitted Radiation
Tropopause as key region - Research with PREMIER
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Summary Wag the tail:
Interhemispheric coupling
Stratospheric transport Wag the dog:
2 and 5-day waves?
Combining observational data with dynamical models yields a more complete picture of the atmospheric circulation.
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