.ON APRIL 2ND a gizmo appearing like a snowfall equipment on the deck of the USS Hornet, a defunct aircraft-carrier anchored in San Francisco Bay, began producing a moisture of salty spray particles. The medical cooperation behind the project, the Marine Cloud Whitening (MCB) program, led by the Educational institution of Washington, is investigating whether such aerosols may help to slow down weather adjustment by means of a form of "geoengineering". What does this term method-- and also why is it thus questionable?