.ON APRIL 2ND a contraption appearing like a snow device on the deck of the USS Hornet, a nonexistent aircraft-carrier anchored in San Francisco Gulf, began creating a moisture of salty aerosol particles. The medical cooperation responsible for the venture, the Marine Cloud Brightening (MCB) programme, led due to the College of Washington, is actually looking into whether such aerosols could assist to decrease climate adjustment through a kind of “geoengineering”. What does this phrase way– and also why is it thus controversial?