Carl Sagan's TV series 'Cosmos' inspired Guus Velders as a teenager

Professor of Air quality and climate interactions Guus Velders

Since April 2017 I am a professor of air quality and climate interactions at IMAU, in addition to my work at the National Institute for Public Health and the Environment (RIVM). With this appointment I try to strengthen the scientific basis of the RIVM work and to make students at IMAU aware of policy processes in The Hague and internationally. I also try to get students interested in an internship at RIVM, so they can experience interactions with policy processes at first hand. I currently work two days a week at IMAU and three days at RIVM. The variety in the work is very nice: doing research, publishing, supervising students, giving lectures, conversations with policy makers in The Hague, interviews with the press, conferences, meetings of the Examination Board, etc.

During the current coronacrisis I work from home, which goes well. RIVM and IMAU activities are now even more intertwined than before, but I like the dynamic. What I miss most are spontaneous meetings with colleagues. That is not only pleasant, but I now also realize that it gives energy and new ideas.

Colleagues of mine at RIVM are now busy fighting the corona virus outbreak, but I am not involved in that. I see Jaap van Dissel and other RIVM colleagues only on TV. I do get a lot of questions from the press about the effects of the lockdown measures on air quality, nitrogen deposition and CO2 emissions. With several colleagues, I am now working on a scientific article on this.

How did it all start for me? As a teenager I was fascinated by Carl Sagan's TV series Cosmos and I think this series contributed to my choice of studying physics at the University of Twente. After my PhD in quantum chemistry in 1992, I ended up at KNMI for fulfilling my military service. There I spent eighteen months modelling air traffic emissions and their effects on the atmosphere. In 1993 I ended up at RIVM as a researcher. Currently, everyone knows RIVM from the nitrogen problems and the coronacrisis, but much more is happening there. I started at RIVM working on the ozone layer and processes in the stratosphere. After that, my field of activity shifted somewhat to processes in the troposphere and modelling air quality in the Netherlands and Europe. Over the past 15 years, the connection of these issues with climate change as well as the link between climate change and public health has received more and more attention. Central at RIVM work are always the societal challenges; what issues are important for society and require attention of citizens and policymakers? The scientific research carried out is also directed towards answering such questions in society.

I have not worked continuously at RIVM. In 1999/2000 I spent six months at NOAA (Boulder, USA), and from 2005 to 2010 I worked for the Environment and Nature Planning Agency, which later became the Netherlands Environmental Assessment Agency (PBL).

Since 1997 I have been part of a UN scientific assessment panel that advises international policymakers on the state of the ozone layer. Every 4 years we write a report for this with an international group of scientists. This is a lot of work, but the interaction with colleagues from other countries is also very inspiring and results in many new partnerships. For example, since 2006, together with colleagues from the US, I have brought the climate benefits of ozone layer policies (under the Montreal Protocol) to the attention of policy makers through scientific publications. Partly based on this research, a global climate treaty was agreed upon in 2016, strongly limiting the future use of hydrofluorocarbons, powerful greenhouse gases used in air-conditioning systems. During this work I often stood with one leg in science and with the other in the international policy arena. Very exciting and you learn a lot.

Currently, it is only 15 minutes for me to bike from IMAU to RIVM, but by the end of 2021 it will only be 1 minute. Then, RIVM moves to a new building in the Utrecht Science Park. Three years later than originally planned, because the original building design did not properly consider the vibrations resulting from the tramway that runs right past it. There is already a lot of cooperation between RIVM and the University, but the hope is that the cooperation will become even stronger through the move. Attending lectures at both places will become easier and you will meet each other more quickly in the park, assuming of course that the corona measures will then be behind us.

Guus Velders