Researchers from the University of Gävle show that the cities in Denmark have become both denser and greener in the last 20 years.
Densification and more greenery in cities have previously often been seen as opposites, so the results from the large survey that was conducted in Denmark surprised the researchers. Other studies have shown an increase in greenery in the landscape as a whole, but here it is revealed that it has also happened in areas where there has also been an increase in population density.
– This shows that cities in our climate zone can become both denser and greener and we know that greenery in cities is important for people’s physical and mental health, says Karl Samuelsson, environmental researcher at the University of Gävle.
The researchers have looked at residential areas in Denmark and included every single address in the whole country, over two million addresses. They have investigated how many people live within a radius of two hundred and fifty meters around each address and how green the area is.
– It is a large data material, which shows over 20 years of development, 1995 to 2016, and what we know is the first time national population density is mapped based on individual address points. To see the development of greenery, we have used satellite images, says Karl Samuelsson.
Karl wants to highlight the remote analysis methods they used, with high-resolution images from satellites that are constantly getting better, where it will be possible to see in even greater detail how the landscape develops.
– It gives us very great opportunities for the future to understand this type of trend to a greater extent.
Climate change is the cause but also urban planning
Although climate change since the mid-90s, with a warmer climate but also more precipitation, is probably what causes this increasing greenery, he emphasizes that urban planning has also made it possible by not building in green areas.
– It is an interesting result, because it is something not really included when talking about these issues. That climate change, at least at our latitudes, will probably make cities greener in the future.
“Important to show that it is possible”
Karl says that it is important to show that it is possible to achieve strategic densifications, without making cities so dense that it has negative public health effects from congestion and stress, and at the same time get the positive effect of the cities being greener in the long run.
Climate scientists predict that we will have more precipitation in our part of the world in the future, but also that the weather will be uneven, with dry periods and periods of very heavy rain.
– The cities of the future could become more resilient if they take advantage of the increased greenery and create a green structure that can withstand this type of extreme weather.
– This does not mean that climate change is good, it is catastrophic and we still have to stop it. But relatively, we in the Nordic countries may not see as catastrophic effects compared to what you can see in other places in the world, says Karl Samuelsson.
Researcher presentation Karl Samuelsson
Text: Douglas Öhrbom, HIG