The risks of global warming were the highlight of the first global art show on climate change that launched several symbolic performances seen from space.
From the US southwest to spots in countries like China, Egypt, India and Spain, thousands of volunteers were coming together for the weeklong photo-performance project that ends November 27, just ahead of UN climate talks in Cancun, Mexico.
Using human bodies as the main media, the show was organized by US environmentalist Bill McKibben and his 350 Earth advocacy group, whose name points to the number of parts per million that most scientists agree is an acceptable upper level of carbon dioxide in the atmosphere.
Currently, that level is about 390 parts per million.
The group brought the global project into focus Saturday in the United States and Spain.
In Santa Fe, New Mexico, more than 1,000 Girl Scouts and other residents holding blue posters crammed into a dry riverbed to form a human "flash flood" depicting where the Santa Fe River should be flowing.
"It's hot in here, there's too much carbon in the atmosphere!" the volunteers chanted.
At 10:53 am, participants flipped their cardboard posters to the blue side so a passing satellite could photograph them from orbit.
People also gathered in Delta Del Ebro, Spain to walk through a huge maze conceived by artist Jorge Rodriguez Gerada, while in New York a painting depicting the New York and New Jersey coastline after a seven-meter (23-foot) rise in sea levels was unveiled on a rooftop and photographed from space.
Thom Yorke, lead singer of rock supergroup Radiohead and an advocate of climate action, put a succinct message about the 350 Earth project on his band's website.
"The plan is to make images visible from the skies to remind those in Cancun that we are running out of time. We can't keep putting this off," Yorke wrote.
On Sunday thousands were gathering at a state park outside Los Angeles to form a giant image of an eagle taking flight over a field of solar panels, while on Monday in Mexico City, thousands of children will create a huge hurricane, with the number 350 depicted in the eye of the storm.
Mumbai will see schoolchildren group together in the shape of an elephant to represent the "elephant in the room" that is climate change.
In Australia, a torch display will form the number "350," in a warning about the risk of more wildfires if global warming is not halted.
And in Iceland, artists at the foot of a receding glacier plan to arrange red rescue tents in the shape of a giant polar bear.
McKibben acknowledged before the project that technical terms can be weak when it comes to inspiring people to change, but he was confident the images photographed from space would resonate with those who see them.
"One of the things I hope this achieves is to remind people that we live on a planet. Just like Venus and Mars, we are a hunk of rock out in space and our future depends on, among other things, the gaseous composition of our atmosphere," McKibben said.
The UN forum has made dismal progress toward a global deal to reduce harmful emissions, and McKibben said was he not optimistic about the Cancun talks.
"I think it is going to be a longer process than everyone has hoped."