.ON APRIL 2ND a contraption resembling a snow machine on the deck of the USS Hornet, an invalid aircraft-carrier moored in San Francisco Bay, started creating a moisture of salty aerosol bits. The medical cooperation behind the project, the Marine Cloud Brightening (MCB) program, led due to the Educational institution of Washington, is actually looking into whether such aerosols could aid to decrease temperature change via a kind of "geoengineering". What does this phrase way-- and also why is it therefore questionable?