The world must do more to combat the climate crisis, a new report declares, because the rate of melting on the Earth's poles and the increase in extreme weather events are projected to be much higher than previosuly predicted.

Those findings came from the United Nations Science Advisory Group United in Science report (pdf), published Sunday ahead of Monday's Climate Action Summit.

"I urge leaders to heed these facts, unite behind the science,and take ambitious, urgent action to halt global heating and set a path toward a safer, more sustainable future for all," U.N. Secretary General António Guterres writes in the report's foreword.

The Earth is coming off of the five warmest years on record, a rise in temperatures expected to contribute to an increase in melting ice in the Arctic and Antarctic and corresponding rising seas worldwide. With more extreme tropical cyclones, fires, heatwaves, and food insecurity on the horizon, the report warns, "there is a growing recognition that climate impacts are hitting harder and sooner than climate assessments indicated even a decade ago."

"Climate change causes and impacts are increasing rather than slowing down," said Climate Summit co-chair Petteri Taalas.

Taalas said that the world needs to do more than double its efforts to reduce emissions if there's a hope of keeping the temperature increases to below the threshold called for the Paris climate deal.

"To stop a global temperature increase of more than 2 degrees Celsius above pre-industrial levels, the level of ambition needs to be tripled," said Taalas. "And to limit the increase to 1.5 degrees, it needs to be multiplied by five."

As The Guardian reported Sunday, that means taking immediate action to curtail the recent rise in coal for energy.

"Governments now need to introduce effective regulation to shut down coal power plants well before the end of their technical lifetime and considerably reduce their use in the meantime," Climate Analytics decarbonization team lead Paola Yanguas Parra said.

At Monday's summit, as Common Dreams reported, youth activist Greta Thunberg tore into world leaders who have not in her view thus far taken scientific findings on the climate crisis seriously. Immediate action is needed, she said.

"For more than 30 years the science has been crystal clear," said Thunberg. "How dare you continue to look away, and come here saying that you are doing enough, when the politics and solutions needed are still nowhere in sight."