Climate Disruption Is Now Locked In. The Next Moves Will Be Crucial.

America is now under siege by climate change in ways that scientists have warned about for years. But there is a second part to their admonition: Decades of growing crisis are already locked into the global ecosystem and cannot be reversed.

This means the kinds of cascading disasters occurring today — drought in the West fueling historic wildfires that send smoke all the way to the East Coast, or parades of tropical storms lining up across the Atlantic to march destructively toward North America — are no longer features of some dystopian future. They are the here and now, worsening for the next generation and perhaps longer, depending on humanity’s willingness to take action.

“I’ve been labeled an alarmist,” said Peter Kalmus, a climate scientist in Los Angeles, where he and millions of others have inhaled dangerously high levels of smoke for weeks. “And I think it’s a lot harder for people to say that I’m being alarmist now.”

Last month, before the skies over San Francisco turned a surreal orange, Death Valley reached 130 degrees Fahrenheit, the highest temperature ever measured on the planet. Dozens of people have perished from the heat in Phoenix, which in July suffered its hottest month on record, only to surpass that milestone in August.