Axial volcano and NeMO Net, click for full size map

The NeMO Net system uses acoustic modems to relay data from seafloor instruments to a buoy at the surface, which in turn sends the data to NOAA's Pacific Marine Environmental Laboratory via satellite. This year three instruments on the seafloor were linked into NeMO Net: two Remote Access Samplers (RAS) in the ASHES vent field, and a Bottom Pressure Recorder (BPR) near the center of the caldera. The map above shows the location of each component of NeMO Net during the latest deployment.

UPDATE: The NeMO Net buoy and the two RAS samplers were recovered on June 5th, 2003 for servicing, after almost a full year in the field. Therefore, the plots below are no longer being updated, but show the data transmitted to shore between July 22, 2002 and June 5, 2003. The buoy and a RAS sampler will be redeployed during the 2003 NeMO Expedition (August 27-September 8), and the display of real-time data on this site will resume then.

3-days with tides |  All Data with tides 3-days without tides |  All Data without tides

The BPR is located near the center of Axial caldera, and precisely measures the pressure of the overlying ocean, as a way to monitor for inflation or deflation of the volcano. The raw BPR data (purple) closely follows predicted ocean tides (black). But after subtracting the tides from the BPR data, the difference (red) shows any sudden changes in seafloor height which may signal the onset of an eruption at the volcano. Three days of pressure data and the cumulative data are displayed in separate plots, with and without tides.