stratospheric dynamics and chemistry
DESCRIPTION
Stratospheric Dynamics and Chemistry. Michel Bourqui , Farid Ait Chaalal, Thomas Milevski, Ryan Muncaster, Andrew Ryzhkov, Barbara Winter. What is the Stratosphere ?. Winter. Summer. WMO, Scientific Assessment of Ozone Depletion: 2002. How is the Stratosphere Working ?. - PowerPoint PPT PresentationTRANSCRIPT
Stratospheric Dynamics and Stratospheric Dynamics and
ChemistryChemistry
Michel Bourqui, Farid Ait Chaalal, Thomas Milevski, Ryan Muncaster, Andrew Ryzhkov, Barbara Winter
What is the Stratosphere ?
Winter Summer
WMO, Scientific Assessment of Ozone Depletion: 2002
How is the Stratosphere Working ?
Source: eiu.edu
Vertical structure of the temperature
The Global Circulation
Tropospheric circulation
Stratospheric circulation
Summer Winter
W = westerly wind
E = easterly wind
The Global Circulation
Stratospheric polar vortex
Summer Winter
W = westerly wind
E = easterly wind
The stratospheric chemistry
tropopause
stratopause
Pole PoleEquator
The stratospheric chemistry
tropopause
Summer Winter
stratopause
Pole PoleEquator
The stratospheric chemistry
O2 O3
UV
tropopause
Summer Winter
stratopause
Pole PoleEquator
The stratospheric chemistry
O2 O3
UV
OO3
tropopause
Summer Winter
stratopause
Pole PoleEquator
The stratospheric chemistry
O2 O3
UV
OO3
tropopause
HO2OH
O3
HO2OH
O3
HO2OH
O3
HO2OH
O3
Summer Winter
stratopause
Pole PoleEquator
The stratospheric chemistry
O2 O3
UV
OO3
tropopause
HO2OH
O3
NO2NO
O3
HO2OH
O3
HO2OH
O3
NO2NO
O3
HO2OH
O3
Summer Winter
stratopause
Pole PoleEquator
The stratospheric chemistry
O2 O3
UV
OO3
tropopause
ClOCl
O3
HO2OH
O3
NO2NO
O3
HO2OH
O3
HO2OH
O3
NO2NO
O3
HO2OH
O3
Summer Winter
stratopause
Pole PoleEquator
The stratospheric chemistry
O2 O3
UV
OO3
tropopause
ClOCl
O3
HO2OH
O3
NO2NO
O3
HO2OH
O3
HO2OH
O3
NO2NO
O3
HO2OH
O3
Summer Winter
stratopause
Pole PoleEquator
densitédensitédensity
1012 molecules cm-3
Ozone concentration, averaged along parallels, forDec – Jan – Feb of 1979 (pre- ozone hole period)
Morphology of the ozone layerA
ltitu
de (
km)
Ozone layer
Chemistry
How is the Stratosphere Working ?
Radiation
Dynamics/Transport
Middle atmosphere:
Chemistry
How is the Stratospere Working ?
Radiation
Dynamics/Transport
Lower atmosphere:
Recent Advances in Stratospheric Research
Modelling:
• 3D Chemistry-Climate Models: first inter-comparison 2002
• Chemical data assimilation: research is starting now…
Observation:
• Ozone observation by satellite since 1990s
• Envisat (EU) satellite: launched March 2002 (chemical composition)
• Aura (USA) satellite: launched January 2004 (chemical composition)
• ACE (CA) satellite: launched May 2003 (chemical composition)
• ADM (EU) satellite: will be launched in 2007 (winds)
• WINDII (CA) satellite: projected for 2009 (winds)
Our current research
• Effect of climate change on the ozone layer
• Development of a fast chemistry scheme
• Chemical data assimilation
• Transport, mixing and chemistry
• Non-linear chemistry in turbulent flows
• Stratosphere-troposphere exchange
• Solar variability and ozone layer
Our current research
• Effect of climate change on the ozone layer
• Development of a fast chemistry scheme
• Chemical data assimilation
• Transport, mixing and chemistry
• Non-linear chemistry in turbulent flows
• Stratosphere-troposphere exchange
• Solar variability and ozone layer
The effet of climate change on the Ozone Layer
CFC scenario (A1), tropospheric concentration, (WMO 1998)
(DU)
(DU)
Ozone column observations (ground-based, WMO 1998)
Ozone depletion due to CFCs
3D Chemistry-Climate Model Forecasts of Ozone Recovery(From Austin et al. 2003)
3D Chemistry-Climate Model Forecasts of Ozone Recovery(From Austin et al. 2003)
Animation_2.wmv
CO2 CH4
N2O
Changes in stratospheric ozone between 1979 and 2060?
CFCs
(WMO 1998, WMO 2001)
Animation_2.wmv
Effects of Greenhouse Gases on Ozone Layer ?
GHG scenarios, tropospheric concentrations (WMO 2001)
Radiative effects (mainly due to CO2)
Dynamical effects (???)
Chemical effects (mainly due to N2O and CH4)
Changes in the distribution of stratospheric ozone
Changes in the total ozone
Potential effects of increasing GHGs on stratospheric ozone:
Increasing concentrations of greenhouse gases (GHGs) : CO2, N2O, CH4, …
(Low concentration of Cly)
Chemical and radiative effects for August
Total ozone change:
Chemical ozone loss slowed down due to temperature decrease
Chemical ozone loss increased due to larger N2O concentration
Total ozone change:
Separated effects of:
N2O
CO2
Chemical and radiative effects for August
Dynamical effects...
Radiative effects (mainly due to CO2)
Dynamical effects (???)
Chemical effects (mainly due to N2O and CH4)
Changes in the distribution of stratospheric ozone
Changes in the total ozone
Potential effects of increasing GHGs on stratospheric ozone:
Increasing concentrations of greenhouse gases (GHGs) : CO2, N2O, CH4, …
(Low concentration of Cly)
Transport, mixing and chemistry
1. Non-linear chemistry in turbulent
flows
2. Stratosphere-troposphere exchange
Transport, mixing and chemistry
WMO, Scientific Assessment of Ozone Depletion: 2002
Winter Summer
Instantaneous tropopause
(2 PVU from ECMWF data)
SH NH
Climatological
tropopause
PVU
Transport, mixing and chemistry
Animation of horizontal cross-section of the tropopause: click here
Transport, mixing and chemistry
A study of the interaction between chemistry and fluid dynamics at the tropopause
Ozone Water vapour OH
Animation of OH: click here
Transport, mixing and chemistry
A study of non-linear chemistry (A+B→C) in turbulent flows
Increasing diffusion,decreasing resolution
time
C c
once
ntra
tion
Transport, mixing and chemistry
Studies of Stratosphere-Troposphere Exchange (STE)
1. High resolution simulation of stratosphere-troposphere exchange episodes
2. Development of a theoretical stochastic model for global STE
3. Characterisation of dilution rate of stratospheric air in the troposphere
4. Impact of STE at the ground and origin of surface air
Transport, mixing and chemistry
Studies of Stratosphere-Troposphere Exchange (STE)
1. High resolution simulation of stratosphere-troposphere exchange episodes
2. Development of a theoretical stochastic model for global STE
3. Characterisation of dilution rate of stratospheric air in the troposphere
4. Impact of STE at the ground and origin of surface air
Transport, mixing and chemistry
Rapid transport between the boundary layer and the stratosphere
WinterStratosphere
Boundary layer
tropopause
700 hPa
Stratosphere
Boundary layer
tropopause
700 hPa
Calculation based upon ERA15 (1979-1993)
Transport, mixing and chemistry
Solar variability and ozone layer
Our approach:
1. Use a magneto-hydrodynamic model of the Sun to generate solar variability (with spectral resolution)
2. Force the photochemical scheme as well as the radiation scheme in our Climate-Chemistry Model troposphere-stratosphere chemistry-climate model.
Solar variability and ozone layer
Froelich& Lean2006
Solar variability and ozone layer
Courtesy: Paul Charbonneau, Universite de Montreal
In Summary:
Research Focus
• Stratosphere• Transport and dynamics• Chemistry• Chemical data assimilation• Ozone layer• Climate• Solar Variability• Future satellite mission STEP
Research Tools
• General Circulation Models• Mesoscale Models• Chemistry models• Trajectory models• Meteorological data (ERA40,…)• Satellite data
Research Infrastructure
• Supercomputer• Desktop computers
Research Collaborations
• University of Toronto• Universite de Montreal• University of Saskatchewan• Canadian Space Agency• MSC (Dorval and Toronto)• University of Reading (UK)• ETHZ (Switzerland)• + many others
http://www.meteo.mcgill.ca/bourqui
http://www.meteo.mcgill.ca/hydroxyl
Office: BH 815
Email: [email protected]
Further information