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. However, the researchers noted that this cooling effect depends on the size of the park and the density of trees. For instance, small pocket parks with scattered trees have minimal impact, while large connected green corridors can create a significant cooling breeze. Interestingly, the study also revealed that green roofs on buildings are more effective at reducing indoor energy use than at lowering street-level temperatures. So, when planning cities, we should prioritize establishing connected green networks rather than isolated small gardens.