Professor Dr Johannes Lelieveld

Research Priorities: Atmospheric chemistry, troposphere, air pollution, climate change, ozone, development of models and measuring devices, HALO research
Johannes Lelieveld is a Dutch atmospheric scientist. The focus of his research is on atmospheric chemistry. He develops aircraft-based measuring programmes and models that describe transport processes in the atmosphere as well as climate change. Recent research is concerned with air pollution’s impact on humans.
Johannes Lelieveld researches the interplay between the atmosphere and processes back on earth. He asks what effect ozone and organic substances have on the climate and how the lifestyles of humans impact atmospheric processes. For his research, he developed computational models that simulate the interaction of chemical and meteorological processes and describe processes like the exchange between the liquid and the gaseous stage of the atmosphere. With these models, he was able to show that processes in the clouds affect the chemistry of ozone. His studies on the influence of tropospheric ozone, methane, and sulphate aerosols on the climate were important contributions for understanding climatic and chemical processes in the atmosphere and to the prognosis of global climate change.
Together with his team, Johannes Lelieveld develops measurement devices which are deployed on ships, satellites, and aircraft. The scientists researched, for example, the influence of the Asian monsoon on the atmosphere’s ability to self-clean during a mission with the HALO research aircraft.
The working group around Johannes Lelieveld also described the risks of nuclear catastrophes like those of Chernobyl and Fukushima with the aid of computer simulations. For this, they developed models with data from all currently-active nuclear power plants on Earth. As a result, they found that the risks associated with a nuclear meltdown are higher than previously expected.
Johannes Lelieveld was also the first to study how different sources for emissions impact the mortality rate in humans: the deaths of more than three million people around the globe are linked to air pollution. In many countries, this means that about ten times as many people die from air pollution than from traffic accidents. 
The research done by Johannes Lelieveld aims to increase the understanding of chemical processes and processes of transportation in the atmosphere in order to sharpen the predictions of air pollution and climate change so that better-suited measures can be taken.