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 four degrees Celsius during heatwaves. However, the effect depends on the park's size and tree density. Small gardens with scattered trees have minimal impact, while large, densely wooded areas create significant cooling. Interestingly, the study also showed that adding water features, like ponds, enhanced the cooling effect by an additional two degrees. So, when designing sustainable cities, planners should prioritize larger, connected green corridors rather than isolated small plots.