Increasingly Warmer

Another heatwave has hit our country in recent weeks, resulting in the equaling of the June air temperature record (38.3 °C) from 2019, and on July 1st, a front that effectively released vast amounts of water from clouds formed at the junction of two air masses swept over us, recording torrential rainfall and strong wind.

Just 10 years ago, we perceived thermal anomalies as a blessing, as our previous weather experiences indicated that we lived in a cold country, and a wave of hot air was a pleasant break in Poland’s cool climate. Today, more and more people feel discomfort and notice that there are increasingly more hot days. Periods of heat are especially troublesome in cities, where the structure of buildings is usually based on materials such as stone or concrete, designed for communication needs and ease of maintenance. Such „concreted” cities become unbearably hot during heatwaves and can also be susceptible to flooding due to torrential rains, as the sealed surface causes a mass of water to suddenly appear in the city with nowhere to absorb. Therefore, the current climate change poses a new challenge for cities to adapt to new weather conditions.

Green-Blue Panacea for Climate Change

A method to mitigate the negative effects of heatwaves and intense rains in the city is the introduction, development, or restoration of green-blue infrastructure. All „green” (trees, shrubs, and lawns) and „blue” (water bodies, streams, wetlands) surfaces act like a sponge, capturing excess water appearing with torrential rains, and during dry periods, they provide a water source for adjacent areas. The water evaporating from these surfaces not only improves the microclimate but also supports plant growth. In this way, instead of hot concrete, we place much cooler (evaporating) elements, making urban living easier. This is particularly important for people with weaker adaptive abilities. Additionally, large urban plants, such as trees, provide us with shade, and their canopies offer living spaces for various organisms (e.g., birds) that cannot live on „bare stone.” In other words, thanks to greenery, we can effectively increase biodiversity in urban environments. Finally, trees can disperse the energy of the wind on their branches, thus protecting urban buildings from storms. In summary, by planting and protecting already existing trees, we make the city more resilient to the currently observed climate change.