So, the biggest challenges lie not in technical feasibility or cost, but in changing social behavior?
Sparber: From a technical point of view a great deal is now possible. We can't switch to 100 percent non-fossil energy overnight, but we can cover some ground if society goes along with it. Many people still see the phase-out of fossil fuels primarily as a sacrifice. The fact that this also offers many economic opportunities is not communicated enough. If, instead of importing fossil energy, we rely on energy efficiency and renewable energies, we can create added value of hundreds of millions of euros annually, even in a small region like South Tyrol, as one of our studies shows. We should also look at costs comprehensively, not just the purchase, but the entire life cycle of a product. An electric car may cost more to buy, but it costs much less to use than a gasoline or diesel vehicle. If I insulate my house, that's up-front financing that pays off later. And it creates added value in the country because it provides work for craftsmen living here.
Of course, all this touches on social issues, because we have to break up systems that have grown and functioned over decades. And like any change, it’s difficult on the one hand, but on the other holds opportunities. And there will also be losers. To ensure that as few as possible suffer and many benefit, it is important to shape this process proactively.
Psenner: Winners and losers: In my opinion, this is a very crucial point. The extent to which crises affect people depends very much on their social status, as the pandemic clearly demonstrated. Inequality has increased even more, and I think that the protest movements, some with fascist tendencies, arise because people are resistant to changes that might make them worse off. If it is clear from a scientific point of view what needs to be done, but a quarter of the population is still not prepared to do it, then this may be because people see themselves as potential losers.
Basically, it's a problem of justice, and if we don't get a grip on that, we won't be able to master the climate crisis either. We scientists are perhaps sometimes deluding ourselves: We think it's enough to know the facts. But that alone does not lead people to change their behavior or their systems.
Timing is another factor of climate change that does not contribute to decisive action: we need to radically reduce CO2 emissions now, but we won't see the effect for another 20 or 30 years.
Sparber: That's precisely why it's important to see the economic opportunities - and to create them. After all, many people think entrepreneurially and get on board when new, promising paths open up. Doing the right thing for the climate also means a better quality of life in the short term in many areas: living comfort is much higher in a renovated building; if there are no cars with combustion engines in our cities, we have less noise, pollutants, and stench.
Psenner: In addition to the time factor, there is also the competition for attention: the pandemic has pushed climate change completely into the background, as has the loss of biodiversity.
The other global environmental crisis ...
Psenner: These crises are closely related; they cannot be considered and solved separately. Especially here in the alpine region, it is very clear how climate change leads to species loss and species displacement. We know the speed at which animal and plant species are disappearing, but most people are not aware that with each species a part of us is also disappearing - a part of our evolutionary heritage, but also of our future. Because preserving biodiversity has very concrete consequences and benefits. Not only for agriculture, but also for medicine: most active medical ingredients come from the plant and animal kingdoms and from microbiology.
One of your institute's projects, Mr. Sparber, is also about biodiversity - green facades and roofs are intended to help cities counteract problems such as heat islands and flooding, while at the same time creating more habitats for animals and plants. How do such nature-based solutions fit in with your technological orientation?
Sparber: They are a nice addition, and I think it is important to think in a versatile way here, to exhaust all possibilities. Greenery is often a solution that has many positive effects, provides cooling, binds fine dust and stores water. Energy and ecological and aesthetic aspects all come together. Green roofs reduce the rooms below overheating, and they can also be combined with technological solutions such as photovoltaics. Of course, this requires more space, but we have that space. If you look at the satellite image of Bozen-Bolzano, you can see that most of the roofs are neither green nor have PV systems, but lie fallow, dead roofs.
Psenner: Of course, such nature-based solutions can only be effective if we reduce emissions at the same time; one cannot just replace one with the other. People often think too briefly here - for example, when experts argue that we simply have to reforest part of our agricultural land because forests remove CO2 from the atmosphere; this would also help biodiversity. I don't think it would make sense, given the ever-increasing world population that needs to be fed, to turn agricultural land back into forests. But it is instructive to look at how these agricultural lands are being used: of the 50 million square kilometers of the Earth's surface where people farm, 40 million are used to produce livestock feed - only 10 million square kilometers are used to grow human food. There is a lot out of balance. I'm not saying that everyone should stop eating meat and the world will be saved - it's not that simple. But we need a change in our way of life.
Sparber: And we need true costs. When you see how cheap meat is compared to other foods, you have to ask yourself the question: is life really worth so little?
How do you feel about the future?
Sparber: I am a moderate optimist. I believe we will get our act together, but there will be consequences. To believe we'll get it right, everything will be all right - that's unrealistic. We have to get our act together very quickly. I think that in two or three generations, we'll look back on this crazy age where we burned masses of coal, oil, and gas. But the question is how many meters the sea level will have risen, how many people will have lost their livelihoods and how much biodiversity will have been lost. It all depends on how quickly we can make the necessary changes.
Psenner: I have dealt with other environmental crises of great magnitude in my career: there was eutrophication of lakes, acid rain, the hole in the ozone layer. The problems were understood and, even if not completely overcome, were contained. There are lessons to be learned from past crises - but it is important to realize that climate change is a problem of a very different dimension. We must do the nearly impossible: limit the warming to 1.5 maximal 2 degrees. We will only succeed if we change, and all adapt to such an extent that as a society we can still live with the change in an environmentally compatible way.