RV Knorr Science Team

Emily at work

14:20 on 21 May 2008: we're just now doing the final CTD cast of the cruise, wrapping up the last station of the last bowtie survey pattern. The weather is lovely: sun's out and the seas are calm. As soon as this is done, we head back towards Reykjavik. I suggested this final survey pattern (in green): yes, it's a joke. I don't understand why so many people are falling for it -- we barely have time for the straight run back to Reykjavik!

Click on the image above for full size.

Courtesy of Mike Sieracki (Bigelow Laboratory) and Tatiana Rynearson (Univ. of Rhode Island).

Thurs 15-May

• Finished 20 km bow tie survey



• Aborted the Biofloat 47 Deployment when check out test revealed that one (out of three) drogue motors was not working properly. After consultation with PI Eric D'Asaro and float engineer Mike Ohmart in Seattle, we decided to go ahead and deploy with two working motors and a slightly gimpy drogue.

News from the Knorr

For the last 6 days, the float has been following an anticyclonic (clockwise) eddy. In an effort to resolve smaller scales of variability in this eddy, we are carrying out a number of small scale surveys. We completed a 20 km-per-side bow tie (13 stations) on Monday-Tuesday and a 40 km-wide Zig Zag (7 m stations) on Tues-Wed. We are currently carrying out another 20 km bow tie.

Combined with the the ship's underway data, float, glider and satellite observations paint an amazing picture of small scale variability in space, time and physiology:\.

Stereomicroscope picture of a foraminifera collected from a CTD bottle fired at 420 m on 2008-05-12. Pseudopodia (the fine hairs) extend out beyond the 100 um cell.

RV Knorr Activites on Monday, 12-May-2008

Today there was much discussion between the Principal Investigators scales of variability in time and space. It was resolved to try to do more smaller bow tie surveys in the near future.

Activities today included:

1. Finished recovery the final four PELAGRA Lagrangian sediment traps around 6:30 Z. Of note, acantharian cysts were discovered in one trap. Acantharia are unique protozoans that produce skeletons composed of strontium sulfate.
2. Completed Primary Productivity cast at Station 50a

Here's a quick summary of activities on Sunday, 11 May 2008:

1. Finished a 15 nm bowtie survey with CTD stations at the vertices.
2. Held a one hour science meeting to discuss observations so far. (Look for an upcoming report summarizing this discussion.)
3. Using a prediction of Biofloat 48's location, pre-positioned ourselves before surfacing. We were within 6 nm of the float when it surfaced.