SO2 EMISSION MEASUREMENT BY DOAS (DIFFERENTIAL OPTICAL ABSORPTION SPECTROSCOPY) AND COSPEC (CORRELATION SPECTROSCOPY) AT MERAPI VOLCANO (INDONESIA)
The SO2 is one of the volcanic gases that can use as indicator of volcano activity.Commonly, SO2 emission is measured by COSPEC (Correlation gtech brush bar Spectroscopy).This equipment has several disadvantages; such as heavy, big in size, difficulty in finding spare part, and expensive.DOAS (Differential Optical Absorption Spectroscopy) is a new