A gaseous cloud rises from the crater of Mauna Loa, center, on the big island of Hawaii, April 4, 1984. The ground is shaking and swelling at Mauna Loa, the largest active volcano in the world, indicating that it could erupt. Scientists say they don't expect that to happen right away but officials on the Big Island of Hawaii are telling residents to be prepared in case it does erupt soon. (AP Photo/John Swart, File)