NeMO-ROPOS Cruise:
This year's NeMO-ROPOS cruise will briefly visit the Cleft segment of the Juan de Fuca Ridge before going on to NeMO at Axial volcano. At Cleft, we will deploy an array of new instruments, which will be part of another seafloor observatory effort sponsored by the NSF/RIDGE Program. Once at NeMO, we will use ROPOS to continue the time-series measurements we have been making on the seafloor since the January 1998 volcanic eruption. This includes taking samples of hydrothermal vent fluids, the microbes that live in them, and the animals that live around them. In 1998, we were able to witness the creation of new hydrothermal vent sites and the first biological colonizers on the new lava flow. Since then we have been returning each year to document how these sites are continuing to change and evolve. We will also be recovering and redeploying a variety of seafloor instruments (including an upgraded near-real time NeMO Net camera system) that allow us to continue our observations of hydrothermal and geological processes between our summer NeMO expeditions. Finally, we will be continuing our high- resolution geologic mapping of the 1998 eruption site, and will begin some new geophysical measurements to tell us if Axial volcano is already inflating with magma and getting ready for its next eruption.

NeMO-CTD Cruise:
The NeMO-CTD cruise will also visit NeMO (Axial Volcano) and the Cleft segment of the Juan de Fuca Ridge. At Axial Volcano we will be making our fourth ctd-cruise since the eruption of January, 1998. We are constructing a time series of observations of hydrothermal activity to understand how vent fields evolve after an eruption. Work there will consist of two principal activities: water sampling and seafloor mooring recoveries and deployments. The water sampling will consist of vertical profiles and near-seafloor tows of instruments to map and sample emissions from hydrothermal vents that form extensive plumes in the deep water around the volcano's summit. Water samples will be analyzed for gases, trace metals, microbiological activity, and suspended particulate matter in order to map the distribution of the plumes. Moorings left at the summit in 1999 will be recovered and the data downloaded at sea. New moorings will be deployed for recovery in 2001. These moorings monitor the fate of the plumes between our yearly cruises.

At the Cleft segment we will be doing similar work to maintain a time series that began in 1986, when a volcanic eruption is believed to have occurred there. Our tracking of hydrothermal activity there is longest such time series anywhere on the seafloor.