Field Notes

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Sherman Island: 2010-09-08 07:50:00 (DOY 251)
Author: Joe Verfaillie
Others: Jaclyn

Summary: Check LGR low flow pressure - maybe pressure controller, SoilCO2 logger having problems - fixed, standard field work.

Sherman
9-1-2010

Cold wind this morning
Pepper weed does not know it
Autumn is coming

Arrived about 7:50PDT with Jaclyn. It was kind of cold and windy. A large bank of high clouds was moving very slowly to the east and smaller puffs of very low clouds or high fog moving to the east a little faster. The field looks green but dry. The peppery weed looks healthy and still has some white flowers. Cows are spread out in the far west.

The LGR was running okay:
6:51PST, 24.26C, 118.23Torr, 15.650usec, 10Hz, 1.851ppm

I low flow mode the pressure is about 30Torr. I checked the internal 2um filter and it seemed okay. The external 2um filter was a little plugged up so I swapped it out. The 40um filter was fine. Still the pressure did not improve. I think this is another pressure controller going bad. I need to check the maintenance record for this analyzer.

I adjusted the bypass valve and when I left the LGR read:
7:38PST, 22.62C, 144.10Torr, 15.812usec, 10Hz, 1.852ppm

I copied data and swapped card. The soilCO2 23X had not reported in about 5 days and didn’t seem to have stored the data internally either. I uploaded the program again and restarted the data logger and Loggernet. This seemed to fix the problem.

Before uploading the program I checked to see if it was using the “if time is” function for output. It wasn’t so it is okay. (Problem of Vaira tipping bucket traced to totalize function not working inside “if time is” function.) I check the other data logger programs and they all were free of this bug. But I need to update the CR1000 program to the new flagged slow output as implemented in the Twitchell CR1000 program.

Also need to seal the SoilCO2 data logger box.

Cleaned the radiometers and checked the tipping bucket.

Need to bring a new lock for the field fence gate. The current one is very difficult to set the combination.

3 photos found

20100908SI_Diablo.jpg ( 2010-09-08 07:53:00 ) Full size: 3648x2736
Clouds and Mt Diablo