Scientists have discovered that summer is lasting longer and feeling hotter around the world. A new study examined weather patterns in ten cities across the globe. Researchers found that summer conditions now last about six more days every ten years. The change is even bigger in Sydney, Australia, where summer grows by fifteen extra days per decade. This is about two and a half times faster than the global average. The study, published in the journal Environmental Research Letters, shows that human-caused climate change is making summers start earlier and feel more intense.