.ON APRIL 2ND a contraption looking like a snowfall device on the deck of the USS Hornet, an obsolete aircraft-carrier anchored in San Francisco Bay, began creating a moisture of salty aerosol bits. The scientific partnership behind the project, the Marine Cloud Brightening (MCB) program, led due to the University of Washington, is actually examining whether such aerosols may assist to slow down weather improvement through a type of "geoengineering". What does this condition mean-- as well as why is it therefore disputable?