Dynamical perspective on the middle atmosphere research in Sweden , SRS-Meeting, Stockholm Heiner Körnich, MISU 1

Overview The middle atmosphere Impact direction? Research areas Outlook Summary 2

By Mark R. Schoeberl 3

Middle atmosphere Climate system + Troposphere Dynamical influence goes Bottom-up Top-down Planetary, gravity and tidal waves Local instability “Downward propagation”? 4

5 Downward propagation of the zonal wind at 60ºN Pressure (hPa) NCEP reanalysis m/s

6 Downward propagation of the zonal wind at 60ºN Pressure (hPa) NCEP reanalysis m/s drag

7 Downward propagation of the zonal wind at 60ºN Pressure (hPa) NCEP reanalysis m/s drag

8 Downward propagation of the zonal wind at 60ºN Pressure (hPa) NCEP reanalysis m/s drag

By Mark R. Schoeberl Noctilucent clouds are very sensitive 9

Photo by Nathan Wilhelm 10

Photo by Nathan Wilhelm 11

Photo by Nathan Wilhelm Sweden, France, Finland, Canada launched on February 20, 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 12

SH NH Hemispheric mean effective NLC Radius weighted with the occurrence frequency Karlsson et al. (GRL 2007) 13

SH NH Hemispheric mean effective NLC Radius weighted with the occurrence frequency Karlsson et al. (GRL 2007) Jan/Jul mean 14

NLC radii from Odin 15

Polar winter stratosphere temperature as planetary wave activity proxy 16

Polar winter stratosphere temperature as planetary wave activity proxy VS. NLC radii from Odin Signals are on the opposite side of globe! After Karlsson et al. (GRL 2007) 17

Interhemispheric coupling – The essential model Temperature response (shaded) and control mean (contours) Körnich and Becker (ASR 2010) 18 NLC ∝ - ΔT

Interhemispheric coupling – The essential model Temperature response (shaded) and control mean (contours) Körnich and Becker (ASR 2010) Planetary waves in winter tropo-stratosphere. Change in the mean flow Feedback between mean flow and gravity waves Change in circulation and NLC 19

Körnich and Becker (ASR 2010) No interhemispheric coupling - because no gravity waves in the Summer hemisphere Planetary waves in winter tropo-stratosphere. Change in the mean flow 20

Northern and southern winter stratosphere as seen by Odin 21 (c) Chalmers

Height of the summer mesopause Kirkwood 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. 22

Annual cycle in H2O observed by Odin Lossow et al. (JGR 2009) 23

Annual cycle in H2O observed by Odin Difference in transport circulation through interhemispheric coupling Lossow et al. (JGR 2009) 24

By Mark R. Schoeberl Probing the stratospheric transport 25

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) 26

Descent observed by Odin Urban et al. (ACP 2009), Orsolini et al. (ACP 2009) 27 Potential temperature

Tracer-tracer correlations by Odin Khosrawi et al. (ACP 2009) Includes both transport and chemistry Diabatic descent in Ozone and N2O Important benchmark for chemical climate models 28

By Mark R. Schoeberl Mesospheric instability 29

Summer mesospheric 2 and 5-day wave Belova et al. (AG 2008) 30 Belova et al. (AG 2008)

Local instability could yield Top-down influence? Summer mesospheric 2 and 5-day wave 31

By Mark R. Schoeberl 32

By Mark R. Schoeberl Measuring winds in the stratosphere 33

34 Atmospheric Dynamics Mission ADM - Aeolus

35 The Earth Explorer Atmospheric Dynamics Mission (ADM-Aeolus) Doppler Wind Lidar yields vertical profiles of the horizontal wind Flexible vertical resolution Accuracy: 2-3 m/s Secondary products: aerosol and cloud properties

By Mark R. Schoeberl PREMIER: Process Exploration through Measurements of Infrared and Millimetre-wave Emitted Radiation Tropopause as key region - Research with PREMIER 36

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. 37