He said he got angry with Falcon for climbing into a compartment in the tethered balloon on Thursday before the balloon was accidentally released.

BBC: 'Balloon boy' found safe at home

The Stratospheric Particle Injection for Climate Engineering project, or SPICE, is a British academic consortium that seeks to mimic the actions of volcanoes like Pinatubo by pumping particles of sulfur dioxide, or similar reflective chemicals, into the stratosphere through a twelve-mile-long pipe held aloft by a balloon at one end and tethered, at the other, to a boat anchored at sea.

NEWYORKER: The Climate Fixers

Tethered to a large helium-filled balloon, the 23-pound Sword, as it's known, was able to climb up and down the long cable while workers kept the balloon steady with guide ropes.

ENGADGET: Space elevator robot reaches 1000 feet