United Nations Secretary-General Antonio Guterres has warned of a “point of no return” in climate change as a result of inadequate efforts to stop it. The U.N. chief spoke in Madrid on Sunday ahead of a 10-day climate conference attended by 25,000 people from around the world. Spain has offered to host the event on short notice after Chile withdrew due to political turmoil there. VOA’s Zlatica Hoke reports.