Nearly 200 nations started online negotiations today to validate a UN Science Report that will anchor autumn summits charged with preventing climate catastrophe on a planetary scale.<br />'' <br />''The report that is going to be finalised is being considered very important worldwide, World Meteorological Organization head Petteri Taalas told some 700 delegates by Zoom.<br />'' <br />''The Intergovernmental Panel on Climate Change (IPCC) assessment is critical for the success of the Glasgow climate conference in November, he said.<br />'' <br />''Record-smashing heatwaves, floods and drought across three continents in recent weeks, all amplified by global warming, have added pressure for decisive action.<br />'' <br />''For years, there were warnings that all of this was possible, that all of this was coming, the UN's Climate Chief Patricia Espinosa, said in a statement.<br />'' <br />''A key G20 summit with climate on the agenda is slated for late October.<br />'' <br />''The world is a different place since the IPCC's last comprehensive overview in 2014 of global heating, past and future.<br />'' <br />''Carbon pollution from burning fossil fuels, methane leaks and agriculture has driven up the thermometer 1.1 degrees Celsius so far.<br />'' <br />''<span style="color: #222222;">Scientists have calculated that greenhouse gas emissions must decline 50 per cent by 2030 and be phased out entirely by 2050 to stay within range of 1.5 degrees Celsius.</span><br />