Monitoring Submarine Volcano With Satellite Remote Sensing

Monitoring submarine volcano is not an easy task compared with land volcano because it is covered by seawater and located in remote area. Satellite remote is a powerful tool for monitoring submarine volcanic activities such as discolored seawater, floating material and volcanic plume. Fukutoku-Okanoba submarine volcano (24°17'0"N, 141°29'6"E) erupted on July 2, 2005. Three days after the eruption, ASTER observed the discolored seawater and the floating materials within the 40 km form the submarine volcano. At the most dense discolored seawater area, reflectance of ASTER band 1 is 3% higher the surrounding seawater. The floating materials are similar in ASTER VNIR reflectance spectra to clouds, however, the floating materials can be separate from clouds using their shape and stereo image features. The extensions of discolored seawater area and floating material detected by ASTER were 6.34 km2 and 1.14 km2, respectively. It is possible to estimate the scale of submarine eruption using the quantitative data derived from satellite remote sensing.