Field Notes

<--2012-08-18 10:00:00 | 2012-08-30 13:00:00-->
Other sites visited today: Sherman Island | Twitchell Rice | West Pond | DWR Corn

Mayberry: 2012-08-23 11:45:00 (DOY 236)
Author: Cove Sturtevant
Others: Sara, Laurie

Summary: Portable: moved tower, spikes on sonic were awry with lots of fouling. Permanent: DO sensors okay, adjusted 7700 settings, put in new 7700 thermoucouple. Vegetation tall and green.

Mayberry
2012-08-23

We arrived just before noon and moved the portable tower. Weather was still sunny and a little less breezy. The vegetation was very green and tall. We pumped up the rear right tire on Dennis’ truck from ~15 psi to 35 psi.

Readings:
CH4: 1.9 ppm
RSSI: 55
CO2: 370 ppm
H2O: 800 mmol m-3
agc ~40

The tower and solar panels had lots of bird fouling, including many drips of blood. Hopefully the bird is okay... The spikes on top of the sonic were awry; one was facing town into the path and another was sideways. I cleaned up some of the fouling near the tips of the transducer heads, cleaned the 7700 and 7500 mirrors/windows, and corrected the spikes on the sonic. I also wet a rag and cleaned up most of the fouling on the solar panel. We did not have a compass so we used Sara’s phone app to align the sonic with N. The 7700 reservoir was nearly full.

After cleaning, readings were:
CH4: 1.9 ppm
RSSI: 75
CO2: 390 ppm
H2O: 740 mmol m-3
acg: 37.5

We arrived at the Mayberry permanent tower at about 12:15 PDT. I did the tower maintenance while Sara and Laurie went out to collect water samples. All the DO sensors looked good (reading ~20) so Sara did not pull any of them. Sara also cleaned the CO2 sensor case.

Tower readings:
CH4: 1.95 ppm
RSSI: 59
CO2: 390 ppm
H2O: 700 mmol m-3
Agc: 43.8

All instruments looked good, although I brushed off some cobwebs surrounding them. The 7700 settings showed the top heater power to be always on for an offset of 2 °C at 7% power. I reset those and other settings to the ones specified on the sheet that Jaclyn made up and taped the sheet to the inside of the box. I then replaced the thermocouple on the 7700 since there was some concern about it from Jaclyn. There appeared to be perhaps some stray cobwebbish material inside the thermocouple shroud and it was hard to examine the thermocouple in the bright sunlight so I figured to just swap it out with the new one and examine the old one in the lab for problems.

1 photos found

MB_autocam_20120823_1245.jpg ( 2012-08-23 12:45:02 ) Full size: 1920x1440
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