The volcanic alert level at Mauna Loa on the Big Island has been downgraded from “;advisory”; to “;normal”;—the lowest since the grading system was put in place several years ago.

Hawaiian Volcano Observatory scientist-in-charge James Kauahikaua said the change means there is a decreasing chance of an imminent eruption at Mauna Loa.

“;It's unlikely to erupt in the very near future,”; he said yesterday.

Kauahikaua said scientists expect some signs such as swelling before an eruption, and there have been no such signs. The last eruption was in 1984.

Mauna Loa has been at the “;advisory”; level since the alert level system was adopted in 2005-2006, and was changed Tuesday to “;normal.”;

The alert system has four levels: “;warning,”; “;watch,”; “;advisory”; and “;normal.”;

Hawaiian Volcano Observatory scientists use various methods to measure changes on the mountain, including global positioning system technology.

Kauahikaua said Mauna Loa inflated after the 1984 eruption, then started to deflate.

He said the mountain began inflating again in mid-2002, and there were swarms of earthquakes in 2004 when inflation started to pick up.

Kauahikaua said since mid- to late 2009 the inflation has tailed off and the global positioning system receivers have not moved.

Kilauea has been erupting since 1983, with a summit vent opening at Halemaumau in 2008.