does climate change now mean regular severe heat waves? future warming is determined by future emissions. if we stop dumping carbon dioxide into the atmosphere the world will stop warming. tomorrow night s leadership debate is cancelled after rishi sunak and liz truss indicate they do not want to take part following last night s encounter when the five rivals attacked each other s records and policies. ukraine s president suspends his security chief and top prosecutor over accusations that members of their departments were collaborating with russia. good afternoon and welcome to bbc news. the uk s first ever red warning for extreme heat has come into effect, meaning there s a danger to life and the threat of major travel disruption. the red alert covers much of england, from london and the south east up to york and manchester. parts of england could be hotter than the western sahara and the caribbean. tomorrow, temperatures could exceed a0 degrees in southern england, which w