.ON APRIL 2ND a device appearing like a snow equipment on the deck of the USS Hornet, an invalid aircraft-carrier tied in San Francisco Gulf, started making a haze of salted spray particles. The clinical partnership responsible for the project, the Marine Cloud Brightening (MCB) programme, led by the Educational institution of Washington, is actually investigating whether such aerosols could help to slow down environment change via a type of "geoengineering". What performs this phrase mean-- as well as why is it thus debatable?