Field Trip Completed

In the week of September 17th - 21st, 2007, a team from AOML visited the La Parguera station to swap out almost every component of the station and to check for structural damage or deterioration. The team consisted of Jules Craynock, Madeleine Adler and Mike Jankulak. Boat operations, in particular the complicated anchoring at the pylon, were carried out by UPRM's Katy Fynn.

Instruments replaced: Wind Monitor / Electronic Compass, Vaisala Weather Station, Surface BIC, Shallow BIC, Deep BIC, Shallow CTD, Deep CTD. Of these, the new Wind Monitor / Compass and the new Vaisala WXT were deployed with new cables; the other five instrument cables were not replaced.

Transmitter work: the GOES HDR transmitter failed following the passage of Hurricane Dean on August 20th. On this trip, the satellite antenna, the antenna cable and the GOES HDR transmitter itself were all replaced.

Electronics work: the station's control unit (or "brain") underwent extensive modifications in its time on land. The power/ground rack (which previously required 14 delicate screwdriver connections to be made/unmade while balancing at the top of the pylon) was replaced, and new hardware was added (and exhaustively labeled) to upgrade this station to the "weather resistant" plugs now used at our newer stations in St. Croix and Jamaica. This also required re-wiring 7 connectors (27 wires) at the top of the stick. Though time-consuming, this upgrade will make future visits significantly easier to accomplish. Also while on land, the station's logger program was updated to send more extensive instrument diagnostics and to collect data from the Vaisala WXT every 30 seconds (as is done in St. Croix and Jamaica) instead of every 6 minutes.

Miscellaneous: the experimental SAMI-pH sensor, which was not connected to the station, was removed and retrieved to land. The SAMI-pCO2 sensor, though non-functional, was left in place for want of a "dummy plug" to protect the station's exposed cable end. The "Groundtruth" CT was connected during reinstallation to ensure its re-wiring had been done correctly. The station needs CT brackets and all new hose clamps on instruments. Other underwater work and observations will likely be covered in a separate blog entry.


Status: as of Saturday, September 22nd, all station instruments appear to be operational, save the SAMI-pCO2 which failed on August 8th and still requires intervention. A temporary glitch in the logger's internal clock appears to have been fixed from land on Thursday evening. Initial problems with the Shallow CTD, the Shallow BIC and the Surface BIC (Thursday morning) appear to have been resolved. Station transmissions are once again reliable and complete. We will be watching the CTD depths and the wind speeds/directions over time to see if they appear consistent.

-- Mike Jankulak

Cleaning Updated August 31

A complete cleaning of the CREWS station in La Parguera, Puerto Rico was performed on August 31, 2007 by Brandi Todd, Rosa Linda Gonzalez and Katie Flynn.

The validation CT was installed at 7:50am and removed at 11:15am. The station was cleaned between 9:05 and 9:55am.

No particulars were observed.

Maintenance Update

A complete cleaning of the CREWS station in La Parguera, Puerto Rico was performed on August 10, 2007 by Wess Merton, Stephanie Williams and Katie Flynn.

The validation CT was installed at 8:45am and removed at 12:00pm. The station was cleaned between 10:05 and 11:30am.

The optical sensors of the radiometers were cleaned, there is some calcareous algae overgrowing such sensors.

The CTDs were cleaned and three of the copper screens were replaced, the fourth remains inaccessible.

SAMI pCO2 Re-installed

Milton Carlo and Jorge Corredor re-installed the SAMI pCO2 today after Chris Langdon and Joanie Kleypas re-filled the SAMI with reagents and worked on the water sampler last week. The SAMI appears to be putting out good data again.

Jim

Update on BICs, SAMI

I cleaned the BICs on May 14. They were very fouled. On May 16 the SAMI was recovered, cleaned, and chemicals replaced. The battery was surprisingly still good,i.e. 13.1 volts so I did not replace it. The SAMI was reinstalled on the stick later in the day. Hopefully it is now reporting data.

Chris Langdon

Maintenance Log

Just a note to let you know the students work this semester.

Here is a small table of when/what for the CREWS.

Francisco

2/1/2007, Complete, CTD validation
2/15/2007, Basic, Cleanded algal growth on chains, and mainframe
3/5/2007, Complete, CTD validation
3/13/2007, Basic, cleaned and examined all gauges, stantions, and chain links
3/27/2007, Complete, CTD validation, need screens
4/17/2007, Basic, cleaned algal growth on chains, and mainframe
5/2/2007, Complete, CTD validiation, changed 3 of 4 screens
5/15/2007, Basic, cleaned algal growth on chains, and mainframe

Samples for Ocean Acidification Studies Taken

On 5/14/07  the BIC sensors were observed to be heavily fouled.  I cleaned
both.

Water samples for TA, DIC and O2 were collected on 5/14. 5/15, 5/16, 5/17 and 5/18.  These data indicate that the SAMI was reading high by 84 uatm before the change of chemicals on 5/16/07.

Jorge's SeaCat CTD was profiled at the stick on 5/15 and 5/18.

The AOML water sampler was deployed at the stck on 5/17 and 5/18 and collected twelve good samples.  Unfortunately the SAMI was not operational that the time.

Chris