.ON APRIL 2ND a gizmo resembling a snowfall maker on the deck of the USS Hornet, an invalid aircraft-carrier moored in San Francisco Gulf, began creating a haze of salted spray fragments. The clinical collaboration responsible for the project, the Marine Cloud Brightening (MCB) program, led by the College of Washington, is looking into whether such sprays may help to decrease temperature modification via a type of "geoengineering". What does this term way-- as well as why is it therefore questionable?