Field Notes

Camilo and I arrived at 10:05 PST. It was a sunny and cool day with hazy horizons. The wetland is brown, except for clumps of green tule. There were many snow geese in the field under the Antioch bridge, south of the gravel road (southeast of the tower). The water level was 81 cm.

Camilo cleaned flux and rad sensors. The wash reservoir was 4/5 full; we topped it off. I downloaded met, camera, and USB GHG data. I also swapped the desiccants for the water level sensor and miniDOT, but did not get the miniDOT data because I forgot the miniUSB cable. We swapped the LI-7500: sn 0073 came down and sn 75H-2180 went up. I uploaded a new calibration file, updated the pressure coefficients, and reset the box.

LI-7500 readings (sn 0073 --> sn 0073 after cleaning --> sn 75H-2180):
CO2 452ppm --> 454 after cleaning --> 462
H2O 230ppm --> 321 after cleaning --> 351
T 12.6C --> 10.6 after cleaning --> 14.7
P 102.4kPa --> 102.4 after cleaning --> 102.4
SS 91--> 98 after cleaning --> 97
LI7700 readings:
CH4 3.2ppm
RSSI 34--> 85 after cleaning

Camilo measured some water/sensor heights around the site and made the diagram below.
Distance from middle of sonic to water level = 533 cm
Distance from water level to ground at the tower = 17 cm
Therefore, distance from middle of sonic to ground at the tower = 550 cm
Water level sensor reading =
Staff gauge = 81 cm
Distance from water level to ground at staff gauge = 119 cm
Distance from water level to ground 20 m ~west of tower = 38 cm

We left at 10:45.

Camilo and I arrived at 10:55. It was a sunny and cool day with hazy horizons. There was lots of cattail fluff flying in the air and on the ground around our tower. There was no water under the tower.

Camilo cleaned flux and rad sensors. I downloaded met, camera, and USB GHG data. I changed the 7550 box sn AIU-0650 nickname from EP-0650 to SWTT-0650. There was a 7700 clock sync error which resolved after I reset the 7550 box. The reservoir was full. We added a missing bolt for the 4-way radiometer and swapped the pi-cam mount (conduit hanger) for one that fit better. The fence post needs a drilled hole before we can add a new turnbuckle and chain.

Camilo measured the sonic orientation (average between the compass and his phone): 29 deg true N

I measured the veg height near the tower. It was an even distribution between knocked down veg (50 cm height), mid-height clumps (150 cm height), and tall clumps (~300 cm height). So, the average veg height is 150 cm, but it’s quite heterogenous.

There were many sleepy wasps in the datalogger box; I left some mothballs for them.

LI-7500 readings:
CO2 445ppm
H2O 312ppm
T 15.4C
P 102.6kPa
SS 98 --> forgot to write after cleaning
LI7700 readings:
CH4 2.8ppm
RSSI 36--> 72 after cleaning

We left at 11:35 PST.