HILO » The lava lake at Kilauea’s Halemaumau crater has been rising gradually in the last few months.

Volcanologists don’t know what the significance of the rise is. It’s possible that the lava could spill out of the pit and on to the crater floor, though this might take months to happen.

The Hawaii Tribune-Herald reported the observatory’s seismologists are also watching an increased number of earthquakes in the upper east rift zone.

Hawaiian Volcanoes Observatory scientist-in-charge Jim Kauahikaua says the increase in seismicity somewhat resembled the prelude to a brief June 2007 eruption in a remote section of Hawaii Volcanoes National Park. But there have also been several similar seismic episodes when nothing happened.

Kilauea is the world’s longest continually erupting volcano. The east rift zone began erupting in 1983.