ISTANBUL The severe heat wave sweeping across Europe since last week is estimated to have caused around 2,300 deaths, according to a study released on Wednesday. Approximately 1,500 (65%) of the estimated 2,300 heat-related deaths are linked to climate change, which brought about a more severe heat wave across the continent, according to the study done by scientists at Imperial College London and the London School of Hygiene and Tropical Medicine. The study said climate change tripled heat-