Atmospheric Chemistry

Abstract

This course provides a general introduction into atmospheric chemistry. It introduces the fundamentals of gas phase reactions, the concept of solubility and reactions in aerosols and in clouds. The learning target is to understand the chemical and physical processes responsible for global as well as regional environmental problems.

Objective

The learning target of this course is a general overview on the most important processes of atmospheric chemistry and the various problems of the anthropogenic impact on the chemical composition of the atmosphere, air quality and climate. The students should understand the chemical processes driving the evolution of the chemical composition in the troposphere and the stratosphere. They will understand how the products of these processes drive regional and global pollution, or affect the ozone layer. The students will also learn how some of these products contribute to particulate matter (aerosol) in the atmosphere, and how this impacts air quality, human health and vulnerable ecosystems.

Content

- Origin and properties of the atmosphere: structure, large scale dynamics, UV radiation - Thermodynamics and kinetics of gas phase reactions: enthalpy and free energy of reactions, rate laws, mechanisms of bimolecular and termolecular reactions. - Tropospheric photochemistry: Photolysis reactions, photochemical O3 formation, role and budget of HOx, dry and wet deposition - Aerosols and clouds: chemical properties, primary and secondary aerosol sources, phase transfer kinetics, solubility and hygroscopicity, N2O5 chemistry, SO2 oxidation, secondary organic aerosols - Air quality: role of planetary boundary layer, summer- versus winter-smog, environmental problems, legislation, long-term trends - Stratospheric chemistry: Chapman cycle, Brewer-Dobson circulation, catalytic ozone destruction cycles, polar ozone hole, Montreal protocol - Global aspects: global budgets of ozone, methane, CO and NOx, air quality - climate interactions

Resources