On March 19th, 2021, I interviewed Prof. Dr. Wilhelm Kuttler. Due to technical difficulties – on that day the servers of Instagram and WhatsApp were also unavailable for certain times – we held this interview by telephone. Prof. Kuttler was extremely well prepared and wrote down answers to the questions in advance. He generously made these available to me. In the following you will find written answers to interesting questions.
Introduce yourself briefly. Who are you? What do you do? What makes you stand out?
My name is Wilhelm Kuttler. I am a retired university professor of climatology. Retired for a few years. During the active time I was chair of applied climatology at the University of Duisburg-Essen. My field of research was and is urban climatology. This deals with the climatic and air-hygienic conditions in urban settlement areas. I am still very interested in climatic issues on all scales. In particular, I have been dealing for a long time with the problem of the impact of global climate change on cities and how to make them fit against climate change. I am head of the Environmental Meteorology Committee at the Association of German Engineers (VDI) in Düsseldorf. This committee drafts guidelines on climatic/air-hygienic issues.
What is climatology? What does a climatologist do?
Climatology is a subfield of meteorology. (physics and chemistry of the atmosphere) Climatology is dedicated to the study of small- and large-scale processes in the atmosphere and with their interactions between hydrosphere, biosphere, lithosphere and cryosphere. Statements about the climate concern not only the mean values of the measured parameters, but also their statistical moments. The investigation of long-term changes is also one of the tasks of climatology (e.g. Global Climate Change). The recording period should – in order to provide comparable data – be 30 years (= climate normal period: 30 years; e.g. 1961-1990). The tasks of a climatologist can thus be diverse, since they cover a wide spectrum.
How do you see the future? What is better and what is worse? Or will everything stay the same?
In my opinion, the various measures to protect the climate are effective, if not immediately, then in the long term. What is important is that there is an increasing rethinking in people’s minds to the effect that they should use all environmental resources more sparingly. Sparingly means using as little of everything as possible. I am confident that we will succeed in this; however, we have only gone part of the way, and efforts must continue or be stepped up.
As early as the 1980s, NASA scientist James E. Hansen warned of a rise in temperature caused by man-made emissions. You have already been able to gather quite a bit of knowledge and life experience. Is the climate crisis really that bad or is the problem merely being made into a trend by the media?
The so-called man-made intervention in the climate should be sufficiently proven by measurements and model-based calculations. Even before J. E. Hansen, a German urban climatologist, P. Albert Kratzer, pointed out the influence of greenhouse gases, especially CO2, on atmospheric warming in the 1930s. The guideline for statements on climate change should be the publications of the IPCC (Intergovernmental Panel on Climate Change), an intergovernmental association of thousands of scientists from all over the world, who present a status report on the earth’s climate every 5-7 years. All countries of the earth are involved in this, so that reliable statements can be assumed. According to this report, the anthropogenic share of climate change is more than 90%. From this it follows that man should act.
To what extent do humans influence the climate? After all, there is also natural climate change.
With the help of modern calculation methods (climate models), the natural climate fluctuations can be separated quite well from those artificially caused by humans. According to this, natural climate change is present, yes of course, it always has been, but it obviously accounts for only a fraction of anthropogenic climate change.
I’m not sure what the state of play is: Are you still doing research on urban climatology and urban air hygiene in Essen? Can you explain what exactly you are doing there and what results you have come to so far?
As an urban climatologist, I investigate the climatic conditions of a city body. Analyses of almost all climatic elements (temperature, humidity, radiation, wind) are made in order to obtain a comprehensive picture of the (preferably) small-scale climatic situation of a city. These investigations are important since they often serve as comparative data – as a basis – for further investigations, for example, when structural changes are made in order to determine in advance what effects a planned construction measure will have. Particularly topical in current urban climate research is answering the question of how cities will respond to the impacts of global climate change and what will happen when heat waves occur or heavy rains with flooding potential fall. Yes, I continue to be involved in research. We have done a lot of research so far in urban climate research. To list you here, there is not enough space for that.
How realistic is it to become climate neutral as a city in the Ruhr region or perhaps even in Germany in general? What are the biggest hurdles? (Time, money, etc…)
Just as globally, energy would have to become more expensive locally in order to use less of it. Creating more forests and greening would be one way, but certainly not enough. The pricing of CO2 emissions has been initiated and will increase in the future, so it can be assumed that less energy will be consumed because it will then become more expensive. Advance emissions trading, 80 euros/t CO2.
Prof. Dr. Kuttler also lists the following things:
- Reduce gray emissions (energy used to create buildings)
- Humans emit about 1 t CO2 per year through their body physiology, but in Germany about 9 t per year through consumerism…
- Demand: Establish and expand training in climatology (in schools) Climatology should become a school subject; teacher training is in a bad way in Germany
- The creation of rock gardens on private property should be prohibited
- in addition, something should be done against ALAN (= artificial light at night), the light pollution at night
- Ensure that in our climate the insulation of buildings is further advanced in order to reduce the expenditure for the heating of buildings
Maybe more specifically related to the Ruhr region: Are there things that have long since become outdated here? What should have been done a long time ago?
- Use cars less often, bicycle and/or public transport more often
- Shorten transport of goods by buying regional products
- Reduce sealing (increase water infiltration)
- Prioritize greening (on surfaces and buildings)
- Increased use of regenerative energies
- Regenerative Energien ev. verstärkt nutzen
- Reduce specific housing and heating energy demand [< 100 kWh/(m2 ∙a)]
- Use climate-friendly building materials and light building colors (possibly photovoltaics)
In conclusion: After all, we want to come out of this interview with a good conscience. Can you think of any good news to fight climate change?
The fundamental problem is that much of what causes global climate change has been known for a long time. There is simply a lack of implementation, that is, a lack of following the pathways charted by science to address climate change. Why were scientists’ recommendations largely followed at Corona and not followed on climate change? Is it possibly because the fear of getting sick from Corona is personally seen as greater than having to suffer from the more general consequences of climate change?