Field Notes

Hill Slough: 2023-11-20 09:40:00 (DOY 324)
Author: Daphne Szutu
Others: Carlos, Ngoc

Summary: Regular data collection/cleaning, lovely fall morning

2023-11-20
Hill Slough

Carlos, Ngoc, and I arrived at 9:40 PST. It was sunny and clear with a light breeze—another beautiful fall day in the Delta. We had a rainstorm two days ago but no major rain forecast for the next 10 days. It was near high tide and the staff gauge read 5.6ft at 9:53 PST.

Carlos downloaded met, cam, and USB data and Ngoc cleaned flux and rad sensors. I supervised. The wash reservoir was ½ full; we refilled it. I also replaced the rad boom bolt. Last time Joe had to put in a temporary, shorter bolt because some of the threads on the lower part of the boom had worn out. The new bolt works great.

I checked the conductivity from the sipper and surface water under the tower.

Sample, Temperature-compensated conductivity, Sample temperature, Time
Porewater, 8.23mS, 13.8C, 10:05 PST
Surface, 6.70mS, 11.4C, 10:06 PST

The 7500 read: 425ppm CO2, 282mmol/m3 H2O, 19.0C, 104kPa, 99SS – 102 after cleaning
The 7700 read: 2.1ppm CO2, 42RSSI – 72 after cleaning

We left at 10:10 PST.

Looking at the EXO data in the lab, fDOM has been steadily decreasing since the the last time it was installed in mid-October and has been ~0 for the last two weeks. I'll pull it up next time to check that it's clean.

1 photos found

HS_picam_20231121_1715.jpg ( 2023-11-21 17:15:05 ) Full size: 1917x1440
Nice sunset at low tide