During recent years two important episodes of effusive activity have been witnessed. The two have contrasting characteristics which are being studied. The eruption during September - December 2004 was more like other episodes of recent years with a relatively fast effusion rate and a duration of about 3 months. In contrast, the event of May 2001 - March 2003 lasted 22 months but with a very low rate of effusion.
Variation in the rate of effusion is being studied and compared to other parameters such as the flux of sulphur dioxide. Thermal characteristics of the 2004 lava flows are being investigated.