Two of the instruments on this mooring produced pressure records - the top Aanderaa and the second MicroCat. The initial rest pressure from the Aanderaa (i.e., the minimum pressure recorded during the first few days, before any indication that the mooring had moved) was 250.1 db, which corresponds to a depth of 249.3 meters using the Reid pressure-depth relationship. This is about one meter deeper than the nominal depth of the instrument. (Nominal depth: the first estimate, which appears in the mooring's installation and recovery logs.) The initial rest pressure from the MicroCat was 398.4 db on 9 March 2004, though it recorded 397.8 db briefly about a month later. 397.8 db corresponds to a depth of 394.4 meters, which is about 3 meters shallower than the nominal depth of the MicroCat. We will make the assumption that the rope was cut accurately to the desired lengths and that our estimates of rope stretch also are accurate. The two rest depths, one slightly deeper than the nominal depth, the other slightly shallower, provide no reason to think that the nominal depths for the instruments and the seafloor are not reasonably accurate. Parenthetically, both pressure records indicate that the mooring slid about 6 meters deeper sometime between 31 May 2004 and 12 June. We will, however, use the initial depths (which in this case are also the nominal depths) as the stated depths of the instruments in this data report.
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