On October 24th and 25th, people in 181 countries came together for the most widespread weekend of environmental action in the planet’s history. At over 5200 events around the world, people gathered to call for strong action and bold leadership on the climate crisis.On Saturday the 24th in New Orleans, a demonstration was held on Tulane University’s campus, led by local environmental groups and students near Tulane University as part of a day of global political action staged by 350.org, an international campaign to address climate change.On drawn to Congo Square in Armstrong Park by the music of 350 musicians, hundreds of New Orleanians became part of 350NOLA, a party with a purpose organized by the Gulf Restoration Network, 1Sky, the Sierra Club and other environmental groups. Attendees ranged from musicians to youth climate activists to families to anyone else curious about the growing climate change movement. Various environmental organizations and progressive groups set up tables with informational pamphlets and friendly faces to chat with. Many photographers and videographers roamed the rally, equally eager to capture the spirit and excitement of the day as the attendees, speakers, and performers were to provide it.While the events on Sunday were part of a global movement, they had a distinctly New Orleans flavor. Marching bands from Sophie B. Wright School, Martin Behrman Charter School and O. Perry Walker High School kept the crowd moving during the two-hour rally.Local trumpeter Leon “Kid Chocolate” Brown invited anyone with an instrument to join in “When the Saints Go Marching In,” drawing cheers from the crowd.At about 1:45 PM after the rally, “Kid Chocolate” led a second-line through the French Quarter with parade goers waving 350 handkerchiefs as they sang and strutted their way to dba, a Frenchmen Street bar to watch the Saints beat Miami and drink delicious Nola Brewery beer.So what does this 350 number even mean?350 is the number that leading scientists say is the safe upper limit for carbon dioxidemeasured in “Parts Per Million” in our atmosphere. 350 PPMit’s the number humanity needs to get back to as soon as possible to avoid runaway climate change. Currently, we are hovering around 390 PPM. The planet is in its danger zone because we’ve poured too much carbon into the atmosphere, and we’re starting to see signs of real trouble: melting ice caps, rising sea-levels, more powerful hurricanes. We need to scramble back as quickly as we can to safety.How do we actually reduce carbon emissions to get to 350?Make no mistakegetting back to 350 means transforming our world. It means building solar arrays instead of coal plants, it means planting trees instead of clear-cutting cypress forests, it means increasing efficiency and decreasing our waste.Where did this 350 number come from?Dr. James Hansen, of NASA, the United States’ space agency, has been researching global warming longer than just about anyone else. He was the first to publicly testify before the U.S. Congress, in June of 1988, that global warming was real. He and his colleagues have used real-world observation, computer simulation, and mountains of data about ancient climates to calculate what constitutes dangerous quantities of carbon in the atmosphere.World leaders will meet in Copenhagen, Denmark, in December to write a new global treaty on cutting emissions, but the current draft doesn’t meet the 350 level. The United States must show strong leadership on this issue if the rest of the world is going to do their part in reducing emissions and transitioning to cleaner, renewable energy like solar and wind.Climate change, rising sea-levels, more intense hurricanes and coastal erosion are all inextricably connected. The GRN and its partner 1Sky will continue to pressure our elected officials in Congress to pass strong, effective climate change legislation that will protect our coast and communities.To view photos from 350NOLA, please visit: http://www.flickr.com/photos/26367809@N03/sets/72157622542519537/Jonathan Henderson is the 1SKy organizer for the Gulf Restoration Network. For more information, contact email@example.com.