Our group covers a broad spectrum of topics, mainly focusing on tropospheric gas and aerosol phase chemistry.
The main current topics are:
Impact of emissions on atmospheric composition
In our group we focus on the impact of natural, biogenic and anthropogenic emissions on the chemical properties of the atmosphere. We use numerical model to optimize present-day emissions based on observations as well as to investigate the outcomes of various emissions scenarios.
Estimate for the average annual 2009.5–2014.5 June–August change in surface ozone from a 4.2% yr−1 NH increase in ethane, and inferred emission increases in propane, butane and pentane isomers from USA OIL and Natural Gas sources. From Detlev et al., Nature Geoscience (2016).
Estimate for the average annual 2009.5–2014.5 June–August change in surface ozone from a 4.2% yr−1 NH increase in ethane, and inferred emission increases in propane, butane and pentane isomers from USA OIL and Natural Gas sources. From Detlev et al., Nature Geoscience (2016).
Oxidation capacity of the atmosphere
The self-cleaning or oxidation capacity of the atmosphere is essential for the removal of pollution in the troposphere. In our group we study the formation and the factors governing the concentration of radicals in the atmosphere, with special focus on hydoxyl radicals (OH), the main radical present in the atmosphere. With numerical simulation we investigate the OH reactivity and the process which controls OH (and other radicals) concentration.
Trace species measured in the OMO aircraft campaign at 300 to 120 hPa (9 to 15 km altitude), with error bars in green, compared with EMAC model results. From Lelieveld et al., Science (2018).
Trace species measured in the OMO aircraft campaign at 300 to 120 hPa (9 to 15 km altitude), with error bars in green, compared with EMAC model results. From Lelieveld et al., Science (2018).
Aerosols nucleation and growth on global scale
Aerosol particles influence climate through aerosol–cloud and aerosol–radiation interactions. A detailed understanding of the sources of aerosol particles is necessary to study their climate and health effects. In our group we study the aerosols budget on a global scale, with special focus on new particle formation (NPF), i.e. nucleation and growth of new aerosol particles from vapours, which is an important source of secondary aerosol particles in the troposphere and planetary boundary layer.
Number concentrations of multi-acid new particles (nucleation mode) at 250-hPa altitude simulated with theglobal model (EMAC). The extra particle number concentrations are shown, that is, relative to the same model without multi-acid nucleation. From Wang et al., Nature (2022).
Number concentrations of multi-acid new particles (nucleation mode) at 250-hPa altitude simulated with theglobal model (EMAC). The extra particle number concentrations are shown, that is, relative to the same model without multi-acid nucleation. From Wang et al., Nature (2022).
Air pollution and its health burden
Long term exposure of air pollution in general, and fine particulate in particular, can have effect on human health. This has been proved by multiple epidemiological studies, although the magnitude of the impact remains difficult to quantify. In our group, we investigate the effect of pollution and its contributing factors to the human health on a global scale.
Graphical representation of estimates of global excess mortality attributable to atmospheric fine particulate (on the left) and ozone (on the righ. The symbols show the average estimates, while error bars represent the 95% confidence levels. The color code denotes different exposure-response functions. From Pozzer et al., Geohealth (2022).
Graphical representation of estimates of global excess mortality attributable to atmospheric fine particulate (on the left) and ozone (on the righ. The symbols show the average estimates, while error bars represent the 95% confidence levels. The color code denotes different exposure-response functions. From Pozzer et al., Geohealth (2022).
