Field Notes

East End: 2022-01-20 09:35:00 (DOY 20)
Author: Daphne Szutu
Others:

Summary: Regular data collection/cleaning, Swapped 7500 for calibration, Changed eddy clock -3min, New datalogger program with Variance-Bowen ET stats, Killed PAR sensor, Put up dfPAR using alternate PAR sensor, Swapped HMP fan, Dropped clipboard in water

2022-01-20
East End

I arrived at 9:35 PST. It was cool and there was fog/haze on the horizons, but otherwise clear, sunny, and calm. The staff gauge read 35cm. There are still green bunches of tules by the road but all the cattail are brown. Occasionally cattail fluff would float by on the wind.

I downloaded met, cam, and USB GHG data.

I uploaded a new datalogger program that calculates and stores the statistics needed for Carlos’s Variance-Bowen ET calculations. The datalogger numbers seemed reasonable with the new program.

I cleaned the flux and rad sensors—there was condensation on the rad sensors and the 7500. The reservoir was ½ empty; I refilled it. I swapped the desiccant for the water level sensor.

I swapped the LI-7500 for calibration: sn 75H-2667 came off and sn 0065 went on the tower. I uploaded a new configuration file and updated the pressure coefficients. I reset the box but there was a 7700 error. I checked the eddy clock and stopped logging to change the 7550 clock -3 min from 11:05 to 11:02 to match the laptop time. This 7550 seems to drift the fastest out of all our 7550s, sometimes it’s fast and sometimes it’s slow compared to the laptop time. Updating the clock resolved the 7700 issue. I restarted logging and confirmed that the 7700 was connected without errors and the USB was logging.

The HMP fan was not working, so I swapped it with a fresh 12V fan. The old fan had a lot of sleepy wasps on it. I couldn’t get one of the HMP shield threaded bolts out (the nut would come off instead of the bolt unscrewing from the top layer), but I worked around it. After I swapped the fan, the red wire on the power cable broke off, so I had to re-strip that wire back. There’s not a lot of slack in this cable, probably because it corrodes and we need to keep cutting it back. I tied up the screw terminal under the HMP shield and made sure the wires on both sides dripped down from the screw terminal. Hopefully water will drip away from the screw terminal and it won’t corrode as quickly.

I installed the dfPAR again after putting in a fresh motor in the lab. The motor now worked, but the PAR sensor did not work because I accidentally killed the sensor by wiring its black and red leads into power. Sending power to places that are not expecting power is usually a pretty good way of killing sensors. Luckily, I was planning on removing the undercanopy PAR sensors today, so I moved zPAR 1 sn 140455 from under the canopy to the dfPAR motor box. I checked that the sensor was level. I brought the bad PAR sn 040411 back to the lab.

I unwired the remaining 2 undercanopy PAR sensors but they still need to be removed from the wetland.

At some point I looked down and saw a big white thing in the water between the scaffolding and the boardwalk path--I realized it was the clipboard and its papers. I’m not sure when the clipboard slipped from the lower boardwalk into the water; maybe my climbing up and down the tower shifted things enough to jostle it.

LI-7500 readings (75H-2667 --> 75H-2667 clean --> 0065):
CO2 546ppm --> 491 --> 480
H2O 274ppm --> 449 --> 456
T 15.3 C --> 13.8 --> 14.4
P 102.8kPa --> 102.8 --> 102.8
SS 80 --> 103 after cleaning --> 100 after swap
LI7700 readings:
CH4 2.9ppm
RSSI 41 --> 80 after cleaning

I left at 12:05.

1 photos found

20220120EE_WaspsFan.jpg ( 2022-01-20 10:20:05 ) Full size: 1440x1920
Sleepy wasps clustered around a broken HMP fan