P18 2016 Weekly Report 08

23 January 2017

Prepared by Rolf Sonnerup 1/20/2017

Weekly report #8

P18_2016_WklyRpt08_fig01Krill caught in Microplastic Net (photo courtesy of Alexander Sidelev's blog entry)


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.  Jay Hooper enthusiastically stayed up past bedtime for a mid-afternoon sensor swap.  When the CTD came on deck, a 1.5” 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