.ON APRIL 2ND a contraption being similar to a snowfall maker on the deck of the USS Hornet, a defunct aircraft-carrier anchored in San Francisco Gulf, began producing a haze of salty aerosol bits. The clinical collaboration responsible for the task, the Marine Cloud Whitening (MCB) programme, led by the College of Washington, is actually checking out whether such aerosols could assist to decrease temperature adjustment through a type of "geoengineering". What does this term method-- and also why is it thus questionable?