SG141 received a final calibration CTD cast before its recovery on 27 June, confirmed aboard the R/V Saemundsson at 14:51 UTC. SG140 received its final calibration CTD cast and was recovered on 28 June, by 14:45 UTC. SG142 is presumed lost.

The science team on the Saemundsson will do more CTDs during their cruise, and are additionally acting as a vessel of opportunity, launching a few floats in the area for a French research project.

Around 25 June @ 22:30 PDT, the field team called in to say that they had finished the NE arm of the search grid and had reached the center of the bowtie, with nary a peep from SG142. They called again on 26 June @ 12:00 PDT to report that they had proceeded through the NW arm and continued to the southern half of the search grid -- and still no sign of the glider. They will finish up the search grid by nightfall, and then (assuming there's no reply from SG142) they will abandon the search.

Seaglider 142 made its last call home on 24 June 01:34 (UTC). So far, there is nothing in the logs to suggest that something was going wrong. It is a mystery that will hopefully be solved by finding the glider via accoustic tracking.

The shore-side crew have identified the 4 possible scenarios that are most likely:

1) It's stuck on the bottom. It could be snagged on something, or it might have suffered a VBD failure. (The VBD, or "Variable Buoyancy Device" is the rubber balloon outside the pressure hull that can be filled with oil to change the glider's buoyancy.)

While SG143 was recovered on 3 June 2008, shortly after Float 48, the remaining three Seagliders began a new survey pattern on the eastern flank of the Reykjanes ridge:

SG140 is executing a large bowtie pattern, and SGs 141 and 142 are repeating a 20-km bowtie: sg141 performing north-south transects on the sides of the bowtie, sg142 performing east-west transects and drawing an hourglass.

We're set to go on the rescue cruise on the R/V Bjarni Saemundsoon, leaving this evening from Reykjavik at 20:30 (or so). Mary Jane Perry is the Chief Scientist, Mike Ohmart is the Float guy, and I'm the Glider 'guy'.

Magnus (an assistant from the Icleandic Marine Research Institute) put Mary Jane's optics instruments on the CTD this morning, while Mike and I prepared float 47 for shipping. The float is much like the glider, in that it's designed so you only need two people to move it around and take it apart.

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:\.

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.

A fried board for a bow thruster and the late arrival of a critical sensor kept the R/V Knorr in Reykjavik harbor until 20:00 on the 1 May, 2008. The upshot was that the science team had several more hours to get everything squared away on board and still had time to run into town for last-minute chocolate supplies. Once underway, the Knorr headed towards the position of Float 47 as reported via ARGOS, pausing in the vicinity of Float 48 for a shakedown CTD cast and the deployment of Dave Checkley's SOLO OPC floats on 2 May.