A string of unprecedented weather and climate events has struck multiple continents in recent weeks, killing hundreds and displacing many more.
Why it matters: Unrelenting heat in Southeast Asia, flooding in Brazil and Texas and other events provide a foreboding preview of the summer season and match scientific expectations of a warming climate.
President Biden is trying to thread a geopolitical needle: working with China on climate while thwarting imports of cheap Chinese electric vehicles, and other low-carbon tech.
Why it matters: The two nations are the world's largest greenhouse gas emitters, accounting for roughly 45% of energy-related carbon dioxide.