But if CO2 is so dangerous, why is "Cool UN" just a publicity stunt, instead of a permanent change?

...and why wasn't it implemented decades ago?

Hot air at UN to curb global warming allegedly a success

"In view of these concrete results, the secretary-general has decided to expand the Cool U.N. initiative ... until Sept. 15," Montas said.

That means some 4,500 U.N. staffers working in the glass-walled 39-story Secretariat building overlooking New York's East River will sweat it out for another week.

The experiment will end, however, before world leaders descend on the United Nations for their annual ministerial meeting the week of Sept. 22.

But Montas said it may be back.

"A winter program is under consideration right now," she said.