State-of-the-art climate models are drastically underestimating how much extreme rainfall is increasing due to global warming, according to a study published Monday, signaling a future of more frequent catastrophic floods unless humanity curbs greenhouse gas emissions. It comes as countries prepare to meet at the COP28 summit in Dubai, which begins later this week, amid concerns that it will soon be impossible to limit long-term warming to 1.5 degrees Celsius, the level scientists say is needed to limit the worst effects of human-caused climate change. Researchers from the Potsdam Institute for Climate Impact Research (PIK) examined the intensity and frequency of extreme daily precipitation over land in 21 "new generation" climate models used by the UN body in its global assessments.  They then compared the changes predicted by the models with those observed in the past, finding that almost all climate models significantly underestimated the rates at which the increase in precipitation extremes escalated with increasing global temperature. (CGTN)