AUV CTD time series measurements
Project Manager/Lead Engineer: Tom O'Reilly
Lead Scientist: Francisco Chavez

Sea trials of MBARI’s Dorado autonomous underwater vehicle (AUV) hardware and software have been very successful to date. Thus far, most Dorado missions have emphasized engineering tests of the vehicle. While engineering tasks remain, the Dorado system has matured to a point where dedicated science missions may be performed as well.

The engineering goal of this project is to move the Dorado system towards a science-operational status. This will be accomplished through regular missions in Monterey Bay from station C1 to M1 (~10 km) in conjunction with the Point Lobos CTD cruises. These missions may eventually supplant portions of the regular Point Lobos CTD cruises. Eventually, the AUV will carry out the mission untended.

The scientific goal of this project is to collect high-resolution sections along the axis of the Monterey submarine canyon of temperature, salinity, oxygen, fluorescence, backscatter and pH over a full annual cycle. We want to answer the following questions:

1. How representative are the profiles at C1 and M1 of the entire section?
2. How does the nature and position of the front that forms between these two stations change seasonally?
3. Can we trace the turbidity signal that is commonplace near the bottom of C1 seaward into the canyon?

We also presume that we will discover phenomena that we are not aware of at present because of the increase in sampling density.

Dorado software (on- and off-vehicle) has been designed largely from an engineering standpoint. Transition to a science-operational status will suggest refinements to the existing system, and may identify new components as well. Components that will likely be refined include vehicle navigation and improvements to fail-safe components for untended, autonomous operation. These improvements will not only benefit the CTD effort, but all science missions.

For these missions, either a hybrid Dorado-Odyssey vehicle ("Dorodyssey") or a "pure" Dorado vehicle would suffice, so long as mission duration does not exceed approximately 8 hours. Longer-duration missions require the use of a Dorado equipped with a fuel cell.