Wednesday, December 14, 2016

Hello everyone,
Finally a proper update on the Buccoo Reef CREWS station.
 On December 1st a team from the IMA towed in the CREWS, cleaned, and started troubleshooting.
On opening the main canister, there was some evidence of salt water intrusion and damp desiccant bags. Not a lot, but enough that small droplets were visible on the batteries. On further investigation, the voltage regulator was not outputting any power. However, it was still charging the batteries as it should. Some corroded connections were cleaned and that solved the power issue.
 Next issue was the modem. The power indicator light was on, but no sign of network activity or antenna signal. We switched the sim card with a new one, but still no change. Finally, we changed the entire modem with a spare one. That solved the communication problem and the CREWS is now transmitting normally.
 There was an unexpected problem with the EXO2 probe and it's umbilical cord. One of the six pins had corroded away. This is probably why we were not seeing the dissolved oxygen and pH readings. This will be corrected before we redeploy the CREWS.
 To prevent any more water intrusion I will do a thorough leak test before deploying, I do not think this was done during the last service.
 That's basically the jist of it and I'll update on the progress of the EXO repairs.
 Jonathan Gomez
Marine Technician
Institute of Marine Affairs

Tuesday, August 2, 2016

some observations about buoy status

The following is a brief status update based on a close examination of the data record, in a similar manner to an earlier update last May.
  • The analog RH/AirT sensor remains nonfunctional. Based on my direct observation of similar problems with the Calabash Caye buoy I believe this is probably a buoy wiring problem and not a failure of the instrument itself.
  • The EXO's CT2 sensor does appear to be more reliable than the problematic CT sensor it replaced. Also there is a clear signal in the salinity data when local calibrations were redone in March and again in May, as described by Jonathan Gomez.
  • DO data disappear following the March visit, the explanation for which can be found in another Jonathan Gomez update.
  • Diagnostic data continue to suggest that the interior of the 'Main' canister is unacceptably moist, which has been true (but worsening) since last December's maintenance operation.
(posted by Mike Jankulak)

Thursday, July 7, 2016

quick buoy update from Jonathan Gomez

[The following is another (slightly edited) email received from Jonathan Gomez on July 7, 2016. It contains information about both Tobago buoys, this one and the one at Angel's Reef near Speyside.]
Just a quick update on the CREWS. There are a couple issues we would like some assistance with.

1. Still no Dissolved oxygen or pH readings are showing up in the data stream from the EXO2 when connected to the CREWS. However, all sensors are showing up and giving readings when connected via Bluetooth when we are calibrating. Please note that the DO sensor was installed in error on the Speyside CREWS last December, but this has since been corrected.

2. We were unable to establish a connection to the CREWS using Loggernet when connected with the supplied umbilical cable. Thus, we were not able to install the software to add the new BIC instruments to the data stream.
(posted by Mike Jankulak)

Thursday, May 26, 2016

met data from this buoy are now feeding NDBC and the world

Last week I began feeding the 10-minute meteorological data from the two Tobago buoys to the National Data Buoy Center (NDBC).  A few days later NDBC notified me that those data feeds have been cleared for release to the Global Telecommunications Systems (GTS), which makes those data available for use by national weather services all over the world.

The Buccoo Reef buoy, which we informally refer to as BUTO1, has officially been designated 42087, which is in keeping with the custom of giving all-numeric designations to buoys.  The NDBC home page for the Buccoo Reef buoy may be found here:

This link has also been added to the 'Links' section on the right-hand side of this blog.

Mike J+

Monday, May 23, 2016

news and photo from Jonathan Gomez

[Note: the following is a slightly edited version of an email received from Jonathan Gomez (who, along with Addison Titus, have been maintaining the two CREWS buoys in Tobago since Jahson Alemu's departure last March) on May 23, 2016. This post is back-dated to that date.]

Click on image to see original size.
I'll give you some updates on the two CREWS.  Myself and Addison removed the EXOs in March for servicing and calibration. Also, both CREWS's support lines and buoy were cleaned of fouling and inspected for wear. Also, in early May the BIC hardware was installed and we took the opportunity to service and calibrate the Buccoo EXO again. The software still needs to be installed for the BIC sensor to be added to the data stream however. We plan to do this in the next few weeks with guidance from Jon Fajans.

There are a couple issues with data from the EXOs however. For the Buccoo EXO, all parameters are functioning fine while doing the calibrations, but when connected to the CREWS we aren't seeing Dissolved Oxygen and pH in the data streams.

It also turned out there was a mix-up with the DO sensor. It was accidentally installed on the Speyside EXO during the December 2015 servicing. This with be corrected on our next trip mentioned above.

I think those are the main issues we have at the moment, if we have any others I'll let you know.

Both ADCPs are deployed and running. We downloaded the last set of data in March. I believe Jahson would do this every 6 months so we are continuing with that schedule for now.

I've attached two photos of the CREWS for you, 'Picture 303' is the Speyside one, and 'Picture 255' is the Buccoo one.
posted by Mike Jankulak

Friday, May 20, 2016

status, based on examination of data stream

Having posted a similar message on the Angel's Reef (Speyside) buoy's blog, I am continuing my data analysis by turning to the Buccoo Reef buoy.  These messages were prompted by an absence of any updates from the field -- basically I am trying to see what we can conclude about local events based only on examination of the data.

As a reminder, this station's recent history includes its annual equipment swapout (December 9th - 10th, 2015), at which time the EXO Sonde was reinstalled after been absent for warranty repairs since July 17st, 2015.  These repairs included an upgrade to a titanium bulkhead and the replacement of the CT module (conductivity/temperature sensor, which reports salinity as well) with an improved CT2 module.  It was hoped that the reengineered CT2 module would eliminate the many problems with failures of the temperature and salinity parameters experienced over this station's lifetime since late 2013.  After the 12/10/2015 swapout was completed, no further updates were received apart from an announcement on February 5th, 2016, that Jahson Alemu would no longer be our primary local contact for the Tobago buoys.

As of May 16th, 2016, the following observations can be made about this buoy's data stream:
  • The EXO Sonde was indeed reconnected during the annual swapout and started producing data on December 10th, 2015, after an absence of nearly five months.
  • The EXO Sonde went offline from March 16th to 19th, 2016. My guess would be that the instrument was removed for three days during some kind of maintenance operation, which seems likely considering that the EXO at the Angel's Reef buoy went offline for five days at the same time (March 18th - 23rd).
  • The Buccoo Reef EXO additionally went offline twice in May, once for two hours on May 1st, 2016, and then again for one day from May 4th - 5th, 2016.
  • Since last December, apart from the aforementioned interruptions in March and May, the EXO seems have produced consistent and reliable sea temperature data.
  • Compared to the performance of the EXO at Angel's Reef, this Buccoo EXO's salinity data are more believable. In the absence of a second conductivity/salinity sensor on-site giving redundant data reports, nothing can be said for certain, but it is at least possible that the CT2 sensor at Buccoo Reef is producing reliable salinity data.
  • As for the other EXO parameters: Turbidities might be okay; Chlorophyll, Blue-Green Algae and FDOM fluctuate above and below zero and those sensors may be bad (or badly calibrated); pH data are either garbage or missing; and dissolved oxygen values may be reasonable.
  • The analog AirT/RH sensor remains offline, as it has been since early 2014. Based on my experience with a similar failure and repair at the Calabash Caye buoy I believe that this is likely to be a problem with buoy wiring and not a failure of the RM Young sensor itself.
  • We do, however, have air temperature and humidity reports from the integrated WXT unit. Although these reports cannot be validated by redundant readings from the analog AirT/RH sensor, they appear to be believable.
  • Wind speeds and directions, as well as barometric pressures, continue to be reported redundantly by multiple sensors, and all appear to be consistent and correct.
  • Of the two diagnostic RH (humidity) sensors with the buoy's two sealed junction boxes (JBs), the "Met" JB humidity levels are perfectly dry, as they have been throughout this buoy's lifetime. However the "Main" JB humidity levels are all consistently above 80% and are a cause for concern.  The Main JB humidity levels were only moderate before the 12/10/2015 annual maintenance operation, and jumped much higher afterwards, suggesting that the Main JB may not have been sealed/dried properly, may require fresh desiccant, or may have developed some kind of leak/crack.  This JB's o-ring, desiccant and interior should be examined at the earliest possible opportunity.
We do not have any reports about how often the EXO Sonde's modules have been recalibrated on-site since December of 2015. According to the manufacturer many of these modules should be recalibrated on a monthly basis.

I will post any further updates that are received at AOML.  The next annual maintenance operation should be carried out this coming December, or earlier.

Mike J+

Friday, February 5, 2016

change in maintenance team for Tobago stations

[This blog update is back-dated to February 5, 2016, which is when AOML received the email announcement reproduced here. -- Mike Jankulak]
Good morning,

I write to informed you that effective March 3rd 2016,  Jahson Alemu would no longer be employed at the IMA.  Mr Jonathan Gomez and Mr Addison Titus (copied on this email) will be responsible for CREWS maintenance until we find a replacement for Mr Alemu.

If there are any concerns/ issues with regards to the CREWS in Tobago, can you please send an email to me and copy Mr Gomez and Mr Titus.

Thanks for your continued cooperation.

Best regards

Rahanna A. Juman, PhD
Principal Research Officer/ Deputy Director (Ag.)
Institute of Marine Affairs
Hilltop Lane, Chaguaramas
Trinidad and Tobago
West Indies