Observations of downward and upward propagating near-inertial waves in the western Gulf Of Mexico

Institute Mexicano Del Petroleo in cooperation with Woods Hole Group from Massachusetts deployed a deepwater mooring in January 2005 off Nautla, Mexico. The mooring was deployed over the continental slope at approximately 1500 m depth. The instrumentation consisted of an RD Instruments, Inc 300 kHz Workhorse Sentinel ADCP, two 75 kHz Workhorse Long Ranger ADCPs, and two Nortek, As Aquadopp single point current meters. CTD surveys of the area were conducted at the time of mooring deployment and recovery to assess vertical stratification of the water column. The deployment produced excellent quality ADCP data covering the upper 950 m of the water column with high temporal and vertical resolution. These data provide unusually clear evidence of the two sets of energetic near-inertial oscillations: waves propagating in the upward direction almost throughout the entire water column up to the upper portion of the pycnocline, and waves propagating downward from their generation region at the base of the mixed layer. Details of the vertical distribution of near-inertial wave properties are presented.