Steve Lambert, WHOI
August 24, 2012
Our northernmost mooring, unit B is located at about 78 degrees north. We will spend most of Friday recovering this mooring and Friday evening turning over the instruments and preparing for deployment the next day. When we recover and redeploy (or 'turn over') a mooring, we take several of the instruments off, download the data and check for any issues and make adjustments as needed. Then we service the instrument giving it new batteries and a new set of data collection parameters for the following year. Other instruments are leap-frogged; in the case of the sediment traps and floatation spheres we brought a set of spares with us and had these prepped ahead of time for the first mooring, then the ones we recovered from the first mooring are prepped for the second and so on. Then the last units recovered are brought back to the lab for use again at another time. As for the smaller instruments like the ADCPs and bottom pressure recorders, those are turned over and put back in the water right away. A spare is brought in the case of failure, but these instruments are rather robust and so the spare will be sent back to the lab. In the case of the MMPs and releases, those are being replaced. A new set of instruments was brought out and all the units recovered will be brought back to the workshop for a complete overhaul. These instruments are much more complicated and history has shown us that a total rebuild is best in the long run.
Friday morning we were greeted with sunshine, cold temps, and a little wind. There are small bits if ice all around and the horizon can be seen for the first time in days. The crew worked well and in spite of equipment issues and a little roll of the ship the recovery was a smooth operation.