Different surfaces have different temperatures. On a normal road with dark asphalt, temperatures can be as high as 50 degrees or more in summer. In a park, the surface has much more favourable properties and has a normal ambient temperature. On the road to the right, the air is stirred. It is worse to get hot in squares where there is no shade from trees and other greenery.
The cooling effect of turf is so great that the surface temperatures on a sunny summer day will be 10 to 14°C cooler than concrete or asphalt. A mown lawn is around 40 degrees. An unmown lawn is around 30 degrees. One square metre of lawn evaporates 2.25 litres of water during a summer day. The lawn needs moisture. A dry lawn does not evaporate water and does not cool the air.
The temperature difference between asphalt in the sun and asphalt under a tree is up to 20 degrees. Under trees and bushes, the asphalt is cooler.
Trees evaporate water in summer. It is 10 to 200 litres per day per tree. Depends on how much the roots take up, so if it's dry or wet. For example, when an alder tree is standing in water, it evaporates up to 180 litres a day. When it's hot, it can be up to 400 litres per day from 1 birch tree. By evaporating water, the tree cools the surroundings. Trees also need watering. Otherwise they can't evaporate water. When a new tree is planted, it must be watered. Each tree needs a different amount of water, the intensity of watering. Some trees are only watered twice a year.
Trees, shrubs and lawns retain and evaporate water and are important for cooling.
They provide a home not only for people, but also for animals, birds and insects. Think of them too.
Clean up after yourselves and don't pollute the park.
Take care of the park together with us, we regularly clean it and renew the furniture.
Martin: "The temperature of the asphalt (49 degrees) and the temperature difference between mowed and unmowed meadow."
Sandra: "If you walk down a street where there are no trees, it's a much higher temperature than where there are trees. That the worst are the flat sidewalks that don't let water through. Water can fall into the sidewalks from the cobblestones, which then evaporates and cools the street. That some colors reflect heat, red and white. We thought it was better to water the tree to the trunk, but that is not the case. That there are pores in the soil where there is room for either water or oxygen, but the roots need both."
Ales: "That temperatures vary across the city. That the city gets more wind from the west. That Prague has such different temperatures when there is no greenery and when there is. I expected the asphalt to be even warmer, but it's still a lot."
“Continue to fight for the planting of new trees. Plant lawns, shrubs and flowers. Make other more appropriate sidewalks (cobblestone, red and white). Build fountains. Water the trees using Mr. Tusher's method."
What can you do for the environment in your home or garden?
Video: PechaKucha Night Here Home Mine (7 min)
Text prepared by Martina Hronová, Sandra Lagronová and Aleš Vojáček
The texts were created thanks to self-advocates and self-advocates, with the support of Rhythm - from client to citizen and Bubahof.
The activities of the association are carried out with the financial support of Municipality of Prague 10, hl. m. Prague a Ministry of Culture of the Czech Republic.
English 
Czech