Field Notes

<--2014-03-13 11:15:00 | 2014-03-27 11:00:00-->
Other sites visited today: Sherman Island

Mayberry: 2014-03-19 09:30:00 (DOY 78)
Author: Cove Sturtevant
Others: Joe, Sara

Summary: Moved flux instruments and autocam to scaffold. Very nice. Installed thermocouples. Swapped 7500.

Author: Cove Sturtevant
Others: Joe, Sara

Mayberry
2014-03-19

We arrived around 09:30 PDT. It was sunny and cool with a light breeze from the north. It warmed up considerably throughout the day as we moved the flux instruments from the tripod to the newly placed tule tower scaffold and installed the tule and water thermocouples. Laurie joined us for a bit to check out the setup.

The new setup is very nice and I think will improve our ability to interpret the spatial variability of the fluxes. There should now be little if any â€˜bermâ€™ fluxes and the flux instruments are at least 1-1.5 meters higher than the previous setup and about that height above the tallest cattail leaves. If we can find a longer pole in the lab we could mount them (safely) maybe 0.5 meter higher.

Joe also moved the autocam over to the scaffold. It is now considerably higher than the previous placement, with a clear view of the footprint.

Thermocouple setup:
Channels 1-8: long rod in middle of channel to east of scaffold (-32, -16, -8, 0, 10, 30, 50, 100 cm w.r.t. soil surface)
Channels 9-16: long rod in tules to west of scaffold (same depths as above)
Channels 17-19: short rod in tules to southeast of scaffold (-8, 0, 10 cm w.r.t. soil surface)
Channels 20-22: short rod in shelf open water to southeast of scaffold (same depths as above)
Channels 23-25: short rod in tules to northwest of scaffold (same depths as above)

After setup, the thermocouple in channel 3 was reading â€“INF and the one in channel 23 was reading high (30 C). Will diagnose next time.

Next time we need to grab instrument orientations and the water pressure reference height.

Still need to bring DO probes for the open water, and new CO2 probes for the tule and open water locations.

Swapped out the 7500 for a freshly calibrated one (removed sn 75H-2180, installed sn 75H-2176). Correctly adjusted pressure cal in 7550.

7500 readings (after swap and tower move):
CO2: 408 ppm
H2O: 330 mmol m-3
signal strength = 88.07%
t: 21.5 Â°C
p = 101.3 kPa
sos = 345.8 m s-1

Current 7700 readings (after tower move):
CH4 = 2.03 ppm
RSSI = 80% (after cleaning)

4 photos found

20140319MB_MuteSwan.jpg ( 2014-03-19 15:21:44 ) Full size: 1920x1440
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