The latest survey results for Nishinoshima Island as of March 2016 are available: No major changes were identified
Geospatial Information Authority of Japan (GSI) took aerial photographs of Nishinoshima Island on March 3rd, 2016 using its Unmanned Aerial Vehicle (UAV). The latest analysis results are now publicly available.
The area was approximately 2.73 square kilometers. The elevation of highest point was approximately 142 meters. The volume was 87,210,000 cubic meters. (Those values are unofficial.)
This photographing was performed by GSI’s Unmanned Aerial Vehicle (UAV) launched from Chichijima Island, Ogasawara Village, Tokyo, with the cooperation of the Ministry of Defense. GSI initiated photographing from December 2013, and interpreted aerial photographs and obtained topographic changes on a regular basis. This was the ninth photographing.
Comparison of measurement results
Comparison of measurement results with aerial photographs and orthophotographs taken around Nishonoshima Island last December is shown in the table below.
Comments from Professor Setsuya Nakada
Earthquake Research Institute, The University of Tokyo, (Leader of The Nishinoshima General Observation Team, Coordinating Committee for Prediction of Volcanic Eruption)
Given the measurement errors, these results can be considered that there was little change in topography between this and last surveys. However, it appears that formation and erosion of sand areas on the coast have slightly been increased in consequence of currents and waves in the ocean.
Considering this time’s results, together with the aerial observation results taken by Japan Coast Guard and analyses of satellite thermal images from last December onward, it seems that Nishinoshima Island ceased its eruption activities at the beginning of last December and stays dormant from then on.
In spite of this, the possibility of future reactivation cannot be completely denied.
The present aerial photographs are being published on the Internet under "GSI Maps".
Related website for information relating to eruption activity in area around Nishinoshima Island
URL: http://www.gsi.go.jp/gyoumu/gyoumu41000.html (in Japanese)