impact of solar uv variability on sudden stratospheric warming with lmdz-reprobus
DESCRIPTION
Impact of solar UV variability on sudden stratospheric warming with LMDz-Reprobus. A. Hauchecorne 1 , S. Bekki 1 , M. Marchand 1 , C. Claud 2 , P. Keckhut 1 , F. Lefèvre 1 , D. Cugnet 1 , S. Lefebvre 1 , F. Lott 2 , G. Thuillier 1 LATMOS, CNRS, UVSQ, UPMC - PowerPoint PPT PresentationTRANSCRIPT
Impact of solar UV variability on sudden stratospheric warming
with LMDz-Reprobus
A. Hauchecorne1, S. Bekki1, M. Marchand1, C. Claud2, P. Keckhut1, F. Lefèvre1, D. Cugnet1, S. Lefebvre1, F. Lott2,
G. Thuillier1
• LATMOS, CNRS, UVSQ, UPMC• Laboratoire de Météorologie Dynamique, CNRS, UPMC, Ecole
Polytechnique
Sun-atmosphere link:possible mechanisms
Total solar irradiance: change surface and tropospheric temperature
Solar UV: O3 production stratospheric temperature change in atmospheric circulation: amplification mechanism ?
Particle precipitations (SPE, GCR, EPP)- SPE and EPP in auroral zone: NOx and HOx atmospheric
chemistry- GCR modulated by solar wind:
condensation nuclei cloudsatmospheric chemistry chemistry
J. McCormack, 2004
Sudden Stratospheric Warming
Dynamics and transport LMDz: • Extended version of the LMDz 4th generation GCM (Lott et al.)• Tropospheric version largely used in the french community• LMDz is the atmospheric component of the IPSL Earth System model
(Dufresne et al.)
Chemistry Reprobus:• Chemistry-transport model (Lefèvre et al.)• Chemical families Ox, NOx, HOx, ClOx, BrOx et CHOx chemistry.• Heterogeneous reactions: on aerosols and PSC particles• PSC sedimentation (dehydration and denitrification) : irreversible vertical
transfer of HNO3 and H2O
CCM LMDz-Reprobus
LMDZ-Reprobus Meteorological analysis ERA40
Zonal mean temperature
LMDz-Reprobus 30 years simulations: Minimum and maximum solar conditions
for the 11-year solar cycle
All the other forcings are kept constant: SSTs, sea ice, stratospheric aerosols, CFCs, GHGs
Difference in polar temperature (K)
MIN
MAX
DIF
90°S 90°N
LMDz-Reprobus solar max – solar min
January
Temperature
February
Wind
LMDz Reprobus solar max – solar min
Temperature
Ozone
Stratosphere-troposphere dynamical coupling
From Baldwin and Dunkerton, JASTP, 2005
Conclusion
The solar UV variability mechanism has been tested in LMDz-ReprobusThere is an impact onstratospheric dynamics (sudden stratospheric warming)
Future plans- Impact on the troposphere - Comparison with other models CMAM, SOCOL, IGCM-FASTOC- Common work on the evaluation of different solar forcings
(TSI, UV, GCR, SPE, EEP)