Grassroots activists around the globe will rally October 24 to try to convince negotiators wrapping up the United Nations global climate treaty this December to target 350 parts per million as the safe upper limit for greenhouse gases. It’s the number, say leading scientists, like James Hansen, Ph.D., and his colleagues at NASA, that humanity needs to cut back to as soon as possible to avoid runaway climate change. The 2008 atmospheric loading hit 387 ppm, according to the Mauna Loa Observatory in Hawaii. That’s up almost 40 percent since the Industrial Revolution and the highest for at least the last 650,000 years.

More than 1,350 grassroots events in 98 countries are gearing up to make a meaningful statement on this Global Day of Climate Action. Everyone is invited to join this necessary call to action to arrest Earth’s climate emergency. To find or schedule a local event on October 24, visit 350.org.