Leg 176 Operational Weather/Sea States
The weather and sea state conditions were extremely variable throughout the leg. Large, long period swells from the south were prevalent much of the time, leading to large vessel heave (2-3 m) on occasion. These swells were often from two different directions, and when coupled with moderate winds (20-30 kt) and an erratic current (0.7-3.2 kt), they created some difficulty for the dynamic positioning (DP) operators in minimizing vessel roll and pitch. On one occasion, gale force 8/9 winds and seas caused us to pull out of the hole. Because of the shallow water, we were getting several yellow (3%) and red (5%) positioning alerts. We felt that it was too rough to safely handle drill collars, so the BHA was left hung off on the elevators for several hours until conditions moderated. All total, one half day was lost due to WOW.

Because of the relatively shallow water, the ASK operating window was very tight. The vessel could only move off station 22 m before a yellow (2%) alarm would trigger. Consideration should be given to relaxing the 2%-4% guidelines somewhat because of the unique circumstances of operating at Site 735.

Current conditions at the site varied significantly and seemed to be driven more by environmental conditions (i.e., the transiting of low pressure cells) rather than tidal or other factors. Currents ranged from nonexistent to as much as 2.3 kt. Generally, the currents were in the 1-2 kt range and originated within a 45° quadrant either out of the north or out of the south.

LAWS/QFAX Weather System
An upgraded LAWS weather system was installed by ODP ET Eric Meissner and is considered to be fully operational. We are now able to capture NOAA 12, NOAA 14, Meteor 3-5, Meteor 3-6, and Meteor 2-21 satellites. We have also been able to collect Wefax data from the geostationary satellite Metrosat 6. The GMS satellite was too low on the horizon for us to capture on this leg.

The last function needed is an audio line connected to the radio room so that the radio operator can use the system to capture the NFAX weather maps. The new system is also able to receive GPS input. Another possible modification would be connecting up a GPS so that position and time updates would not have to be input by keyboard. In addition to hardware installation, the mates have also been trained on how to use the new system.

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