Course description:
This course introduces the air pollution modelling in urban and regional scales. The atmospheric system is first presented with the atmospheric boundary layer dynamics, its specificity in urban areas. Then the atmospheric composition is presented with the gases and particles chemical species to be considered for pollution, and a history of air quality trends over recent decades. Modelling systems are described covering the calculation of meteorology, emissions (anthropogenic, biogenic, fires, dust ..) as well as chemistry and transport of chemical species. The various deterministic modelling techniques, direct, adjoint and with data assimilation show the current level of understanding of the system and its limitations. Various current applications are described as extreme case analysis, scenario studies until operational forecast. To estimate the simulations quality, data comparisons methods are explained, from surface stations to the new satellite measurements available. These models are presented in the context of the current air quality policies in Europe and key locks are presented to understand realistic reduction choices being discussed for air quality improvement. Finally, recent studies dedicated to quantify the impact of pollution on health (urban particles and pollen) are discussed.

The course is given over 8 sessions of 2h each and 14h of lab experiments.
Course 1:
Modelling of the regional atmospheric system:
Generalities about main source and sinks
The mesoscale
Surface heterogeneities
Land/sea, topographic circulations
The atmospheric boundary layer:
turbulence
the diurnal cycle: neutrality and unstabilities
The urban meteorology
Course 2:
Chemical composition of the troposphere:
gaseous and particules species to study
relative amount
life time
Gaseous tropospheric chemistry
The radical cycle
photochemistry
NOx and VOCs chemistry
chemical regimes
Course 3:
Aerosols modelling:
Anthropogenic, biogenic and natural
Organic aerosols
size distribution
aerosol optical depth calculation
Course 4:
The main pollution sources modelling:
Anthropogenic emissions
Biogenic emissions
Fires emissions
Natural sources: volcanos and mineral dust
Course 5:
The main pollution sinks modelling:
The dry deposition
The wet deposition and scavenging
Course 6:
The air quality:
Air quality monitoring: networks, policies
Atmospheric concentrations measurements:
Network mesurements: instruments, data acquisition, detection limits
Fields campaigns: interest and examples
Satellites: Main capabilities and limitations
The air quality regulatories:
The need to develop forecasting system.
Main model types: lagrangian, eulerian, 1D to 3D, from global to urban
The spatio-temporal resolutions
The numerical system to solve
Numerical schemes: chemistry, transport and associated solvers
Forecast systems: strengths and weaknesses
Course 7:
Chemistry-transport modelling
On-line and off-line coupling
Mandatory meteo variables
Main principle of a parameterization
Sensitivity of concentrations to input parameters
Data assimilation: principle, advantages and limitations
Inverse modelling
Course 8:
Impacts of air pollution
Impact on environment: feedbacks between vegetation and surface atmospheric concentrations
Impact on health in urbanized environments
Modelling of pollen and allergies

Dernière mise à jour : mercredi 20 avril 2011