Field Notes
<--2003-05-09 04:45:00 | 2003-05-14 00:00:00-->Phenocam link: Searching...
Tonzi: 2003-05-12 00:00:00 (DOY 132)
Author: Dennis Baldocchi
Others:
Summary: Notes on the Tower CO2 profile system
| CO2 profile system--- 12May03 The CO2 profile system installed at the Tonzi tower in April 2003 was initially configured in the following manner: Program initializes and begins to simultaneously draw an air sample through 4 sample ports until reaching the beginning of the first half hour period. At the beginning of the half hour sample ports 2,3 and 4 close and sample air is drawn through sample port 1 for 20 seconds flushing the manifold. At the end of 20 seconds the data logger begins taking 20 data samples every 0.25 seconds. After the 20th data sample is taken from port 1, sample port 2 opens and sample port 1 closes. Sample port 2 flushes the manifold for 20 seconds, takes 20 samples (0.25 second intervals) and then advances to sample ports 3 and then 4. Sequential measurements from the 4 sample ports are performed 16 times during a given half-hour period. At the end of the 16th iteration statistics are calculated and output for those 16 iterations for each of the 4 ports. Now the system once again begins to simultaneously draw sample air through the 4 sample ports until it once again reaches the beginning of the next half hour period and begins the measurement sequence anew. Similarly, a zero/span sequence is performed each day at 24:00. This sequence flushes sample port 1 for 60 seconds with nitrogen and then begins taking 40 measurements each 0.25 seconds apart. After the 40th measurement is taken the nitrogen is removed and a span gas of known CO2 concentration is introduced. After a 60 second flush period 40 measurements are made at 0.25 second intervals. Statistics are then calculated and output for the zero/span sequence. At the beginning of the next half-hour period the system leaves the zero/span mode returns to the sampling mode. Zero/span gas is introduced at the input of sample line 1 and must traverse a filter and about 40 feet of Teflon tube to reach the LI800 analyzer. Notes: This is a very wet spring, with LATE Spring rains. The grass is much greener and later than in the past. |
Field Data
No tank data
No TZ Well data found
No TZ Moisture Point data found
No VR Moisture Point data found
No TZ grass heigth found
No VR grass heigth found
No TZ Tree DBH found
No water potential data found
No TZ Grass Biomass data found
No TZ OakLeaves Biomass data found
No TZ PineNeedles Biomass data found
0 photos found
16 sets found
No data found for TZ_Fenergy.
11 TZ_tmet graphs found
No data found for TZ_soilco2.
Can't check TZ_mixed
3 TZ_mixed graphs found
No data found for TZ_fflux.
8 TZ_fmet graphs found
No data found for TZ_tram.
No data found for TZ_co2prof.
No data found for TZ_irt.
No data found for TZ_windprof.
No data found for TZ_tflux.
2 TZ_sm graphs found
Can't check TZ_met
1 TZ_met graphs found
Can't check TZVR_mixed
No data found for TZ_osu.
No data found for TZ_fd.
Tonzi Z-cam data