Today, in our environmental science lecture, we'll discuss urban green spaces. A recent study in Melbourne found that parks can reduce local temperatures by up to 4 degrees Celsius during heatwaves. This cooling effect is mainly due to shade and evapotranspiration from trees. However, the researchers noted that the benefit is strongest within 100 meters of the park. Beyond that distance, the temperature difference drops significantly. Also, they observed that larger parks with diverse tree species provide more consistent cooling than smaller, grassy areas. So, for city planners, it's not just about having green spaces, but their size and design matter.