When we went to the 350.org action in Times Square on Saturday, my four-year-old Bella insisted that "the lady" paint 350 on her face.
350 is the number of parts per million carbon dioxide we can afford to have in the atmosphere without the global warming tipping point occurring
I was honored with the chance to say a few words to the crowd. "What's the most important number in the world?" I shouted into the mike.
"350!" the crowd shouted back.
Later, when we got home, Bella's mom called on the phone.
"Mom," Bella said. "Do you know about 350?"
"What about it, hon?"
"It's the most important number in the world," my little girl said.
Photo credit: Nancy Kaszerman