Alok Sharma, the president of this years COP26 talks in Glasgow, Scotland, has promised to speak frankly about what is getting accomplished - or not - at the most-watched climate summit in years. On Tuesday, that meant a dash of realism with his usual hopefulness.

Carbon dioxide emissions are set to rise this year after a three-year pause, scientists said at UN climate talks Monday, warning that "time is running out", even as White House officials used the occasion to champion the fossil fuels that drive global warming.