By David Stanway SINGAPORE (Reuters) - Human-induced climate change has played an "absolutely overwhelming" role in the extreme heatwaves that have swept across North America, Europe and China this month, according to an assessment by scientists published on Tuesday. Throughout July, extreme weather has caused havoc across the planet, with temperatures breaking records in China, the United States and southern Europe, sparking forest fires, water shortages and a rise in heat-related hospital admissions. Over the weekend, thousands of tourists were evacuated from the Greek island of Rhodes to es...