data feeds coming back online

The CHAMP web server has recovered to the point where the "near real time" data reports are once again online.  These reports are updated once per hour, and contain 12 hours' worth of data:

• Hourly Summary
• Hourly Detail
• Hourly Winds (6-minute data)

These reports are updated once per day, and contain 3 days' worth of data:

• Daily Summary
• Daily Detail
• Daily Winds (6-minute data)

Also, the feed of LPPR1 data to the National Data Buoy Center has resumed.  NDBC knows this station under the name "LPRP4" and its home page for the station is here:

•  NDBC's LPRP4 Station

NDBC's site has various views and graphs of recent data, and also some archives of older data.

The station has been running nearly 3 weeks since its overhaul, and for the most part the news is good.  The new batteries appear to be fully charged and maintain voltage levels a bit higher than seen with the old batteries.  All instruments continue to communicate with the logger.  The two SeaBird CTDs are showing an agreement on salinity measurements that was rarely found with the Teledyne CTDs we usually use, which raises hopes for better CTD performance this year.

The GOES transmissions were spotty at first but as of this writing we are receiving 100% of the expected transmissions for over a week.  Initial (post-overhaul) transmitter performance was running at only 50% success rates for a period of many days.  It's not clear why this should be so, and why performance has so substantially improved.  One possibility is that the satellite antenna (which was not replaced on this trip), whose underside was showing signs of peeling paint, has had some kind of moisture damage; or that the satellite antenna cable was damaged.  This wouldn't explain why transmissions improved, however.  Another possibility that occurs to me is perhaps the transmitter antenna is partially blocked... by birds.  We see lots of boobies resting on the aerial instruments at this station, but it's not known if they could "block" the satellite transmissions by sitting on the antenna.  We may want to device an antenna bird-deterrent for this site.

If there's bad news, then it's related to the secondary measurements of winds by the "WXT" Weather Transmitter made by Vaisala.  On this trip we unexpectedly found that the custom-made bird deterrent on the old WXT had been overcome by the boobies.  Five of the six spikes were broken off and the sixth was bent sideways.  That meant we had no deterrent for the new WXT, and indeed we are already seeing the unrealistically-high wind signals that suggest the sonic transducers are being blocked by birds.  However, we still have wind data from the anemometer, and the WXT will continue to report other measurements (air temperature and pressure, humidity).  The WXT's precipitation reports may also be unreliable.

But all in all the news is good!

Mike J+

2012 swapout: aftermath (5 of 5)

The AOML team consisting of Pamela Fletcher (UF/SeaGrant) and Mike Jankulak (UM/CIMAS) returned to Fort Lauderdale on Friday, August 31st, 2012.

All evidence so far indicates that the swapout operation was successful in its goals:  to swap out all meteorological and oceanographic instruments, to replace all underwater cables, to install new rechargeable batteries, to deploy SeaBird Microcat CTDs and their new programming.  Data obtained from the in-boat radio connection and the GOES satellite transmissions suggest that all of these sensors are operational, and have remained so during the station's first four days of uptime.

One possible area of concern is the station's satellite transmitter.  Since the station was not operational for the preceding four months, there was no recent data on how well its satellite transmitter (and its associated antennae) were working.  The station has for quite some time shown a pattern of dropping transmissions chiefly in the nighttime hours, and it was believed that this was caused by failing batteries (and should therefore now be resolved).

However, the station's first four days of operation have shown decidedly mixed transmission results.  These are:

• August 31st:  23 of 24 transmissions received
• September 1st:  13 of 24 transmissions received
• September 2nd:  13 of 24 transmissions received
• September 3rd:  23 of 23 (so far) transmissions received

These numbers suggest that there may be something wrong with the station's GOES transmitter, and that this condition may be intermittent.  More time will be needed to observe the station's transmitter performance and determine whether a particular fault can be identified.  One possible explanation is the previously-noted (mentioned here, with photo) observation of the transmitter's satellite antenna with its peeling paint and the possible implications for moisture intrusion.  Another factor may be that the new batteries have not yet been fully charged by the solar panels, although they achieve higher voltages with each passing day.

In any case, problems with the transmitter should not affect station sensors and data collection which appear, as of this writing, to be fully operational.