Today we're discussing the impact of urban green spaces. A recent study in Melbourne found that parks can reduce local temperatures by up to 4 degrees Celsius during heatwaves. Interestingly, the cooling effect extends about 100 meters beyond the park boundary. However, the study also noted that smaller parks, less than 2 hectares, have minimal impact. The researchers suggest that vertical gardens on buildings could be a more effective solution in densely built areas where large parks are impractical.