On the trail of urban heat islands

Moritz Burger graduated second best in his class at the Graduate School of Climate Sciences and has been awarded a 2020 Oeschger Young Scientist's Prize for this achievement. Now, as he writes his doctoral thesis, he remains true to his master’s thesis topic: Bern’s urban climate. 

Porträt von Moritz Burger

He lives in Bern and knows the capital city like the back of his hand. Besides attending grammar school and completing his bachelor’s and master’s studies there, Moritz Burger has made Bern his research subject. His topic: the summer heat, or more precisely, Bern’s urban heat islands.

Like many things in Moritz Burger’s life, this field of research came about rather by chance. “I like to let myself be guided a bit by the things that come my way,” he says. That’s exactly how he came up with the idea of earning a master’s in climate sciences. While doing his bachelor’s degree in geography, Moritz Burger liked the mix between the exact and social sciences. After a semester abroad in Spain, however, he felt the need to specialize more. That’s why he finally decided on the climate master’s degree: broadly diversified in terms of content and with a specialization of his choice.

The Bernese scientist doesn’t regret his decision to keep studying, noting that this degree feels more tangible than his bachelor’s. “Now I’m a climate scientist with a background in geography.”

Heat maps for the city of Bern

For his master’s thesis, he analysed climatological data collected by the OCCR’s Climatology Group in 2018 and 2019. Gathering this data involved some 80 automated stations that measured Bern’s air temperatures every ten minutes. With the help of data on land use such as green spaces or wetlands, the young climate scientist then interpolated heat maps for the city of Bern.

Now Moritz Burger is working on his dissertation in this same field. “I was asked if I’d like to further develop the heat island project based on my master’s thesis,” he says – another happy coincidence.

Among other things, his current research work on Bern’s urban climate will focus on predicting which parts of the city will get hotter – and how much hotter – within a matter of hours. This data will be incorporated into a project on the consequences of heat waves on human health by the OCCR’s Climate Change and Health group. For another part of his dissertation, Moritz Burger wants to find out what part of the temperature increase in Bern is due to climate change and what part to urban development. To do this, he is modelling the urban climate.

The basis for answering the various questions is not only the current measurement data on Bern’s urban climate, but also the results of a measurement campaign from the years 1972-1974. Half a century ago, the Geographical Institute of the University of Bern was already operating 50 measurement stations. But only some of them were equipped with temperature sensors. At that time, the focus was not on urban heat islands, but on the air pollutants that plagued the city. At least this problem is no longer so pressing. The summer heat, on the other hand, will probably be part of everyday life in Bern and many other Swiss cities in the future.

(February 2021)