P18 Cruise report #8

sioword-multiCruise Report


After we gloated about our good weather fortunes last week, King Neptune returned the favor with a weekend blow: 25-30 Knot South winds, seas 10-15 ft were our new normal during the 14-16th. Although our transits were slowed, sometimes drastically, we continued operations. Since the 17th, however, we’ve been riding the Western side of a low (< 1000 mb) with very little pressure gradient. Cloudy skies, cold (2-4°C), but with moderate winds 10-15 knots, squalls to 25.

It snowed today. We’re not missing winter after all, with the added bonus that the sun keeps summer hours: rising a little after 5, setting around 11.

We continue to operate on the aft winch with very few problems with the wire or the CTD. We had a problem on the downcast at one station.nJay Hooper enthusiastically stayed up past bedtime for a mid-afternoon sensor swap. When the CTD came on deck, a 1.5cm shrimp was discovered jammed in the primary sensor. Problem solved. Bedtime.

This week marked an important, and sad milestone: We deployed our last drifter at 59°S. The instructions are designed with modelers in mind: Unwrap, then toss the thing overboard. For a time, Chief Sci. was trusted with this task. He should not have bragged about how fun it is.

Our schedule still provides for half-degree spacings to 70°S with a healthy (now that the 40s and 50s are behind us) weather / mechanical cushion of ~ two days remaining. However, ice conditions may limit our Antarctic approach to ~68°S. Our weather cushion is not enough to pursue reoccupation of P17E, so we are eyeing instead the option of straying a few degrees West of the 103°W meridian, where ice conditions may be more favorable. There is a SOCCOM float approx. On our return, we’ll chase floats for calibration/validation as part of SOCCOM.

Box score: P18 Leg 2, Week 3

    • 23 Full depth CTD stations occupied, 46°S to 57°30’S, 103°W
    • 7 Floats deployed
    • Our final (sniff) four drifters deployed
    • Yves Plancherel still free to saunter about
    • Ice Cream still in good supply