SGP/PGS/C1 - Incorrect 60m Data

Precise Gas system (PGS) data at 60m (channel 4) are incorrect. This problem is due to a 
freezing rain and ice storm that hit SGP Central facility on January 5, 2005. The 60m 
tower inlet was clogged with ice and consequently, no air was supplied to the PGS instrument.

• 90% confidence limit of co2ppm(co2ppm_se)
• p-value of co2 readings during the last 30sec of 3min period of raw data(co2mv_slope_pval)
• Pressure of channel 4(pres4)
• reading of CO2 in mV(co2mv)
• Slope of CO2 readings during last 30sec of 3min period of raw data(co2mv_slope)
• calculated concentration of CO2(co2ppm)
• 90% confidence limint of co2mv_slope(co2mv_slope_se)
• pressure inside the IRGA box measured by the pressure controller(pres_ctrlr)
• flow rate measured by the mass flow controller(flow_rate)
• standard deviation of co2mv(co2mv_se)

SGP/PGS/C1 - Suspicious 4m data

KNF pump for 4m height (channel 2) started to leak on November 24, 2004 and sampled air 
was consequently "contaminated" by indoor air. The pump was replaced on August 19, 2005.

• 90% confidence limit of co2ppm(co2ppm_se)
• calculated concentration of CO2(co2ppm)

SGP/PGS/C1 - Suspicious 2m data

KNF pump for 2m height (channel 1) started to leak on July 22, 2004 and sampled air was 
consequently "contaminated" by indoor air. The pump was replaced on August 19, 2005.

• 90% confidence limit of co2ppm(co2ppm_se)
• calculated concentration of CO2(co2ppm)

SGP/PGS/C1 - Suspicious 25m and 60m data

KNF pumps for 25m and 60m height (channel 3 and channel 4) started to leak on March 31, 
2005 and sampled air was consequently "contaminated" by indoor air. The pumps were replaced 
on August 19, 2005.

• 90% confidence limit of co2ppm(co2ppm_se)
• calculated concentration of CO2(co2ppm)

SGP/PGS/C1 - Updated files

Dew point temperature (dpt) sensor (Vaisala DMT 142) was added to the system on May 24, 
2005 to assess water trapping system efficiency. Consequently, variable "dpt" is filled 
with missing values (-999.99) prior measurements start date (May 24, 2005).

• 90% confidence limit of co2ppm(co2ppm_se)
• Pressure of channel 2(pres2)
• reading of CO2 in mV(co2mv)
• reference CO2 reading in mV(ref)
• calibration coefficient 1 (quadratic fit)(coeff1)
• calibration coefficient 3 (quadratic fit)(coeff3)
• longitude of instument location(site_longitude)
• pressure inside the IRGA box measured by the pressure controller(pres_ctrlr)
• Temperature in refigerator(t_refrig)
• flow rate measured by the mass flow controller(flow_rate)
• calibration coefficient 2 (quadratic fit) 90% confidence limit(coeff2_se)
• p-value of co2 readings during the last 30sec of 3min period of raw data(co2mv_slope_pval)
• Sequential data channel number. See channel_explanation global attribute.(channel)
• Number of measurements for indicated channel(nmeas)
• calculated concentration of CO2(co2ppm)
• latitude of instument location(site_latitude)
• calibration coefficient 2 (quadratic fit)(coeff2)
• Second level of QC, see reject_flag_explanation global attribute(reject_flag)
• Pressure of channel 1(pres1)
• Date and time in alternate form(yyyymmddhhmmss)
• height of tower base from sea level(site_elevation)
• Slope of CO2 readings during last 30sec of 3min period of raw data(co2mv_slope)
• flag indicating which channel isotope sample was taken from(iso)
• Time offset from base_time(base_time)
• Pressure of channel 3(pres3)
• calibration coefficient 3 (quadratic fit) 90% confidence limit(coeff3_se)
• 90% confidence limint of co2mv_slope(co2mv_slope_se)
• temperature of the IRGA(t_irga)
• adjusted CO2(adj)
• r-squared of quadratic fit(r2)
• Pressure of channel 4(pres4)
• calibration coefficient 1 (quadratic fit) 90% confidence limit(coeff1_se)
• First level of QC, see warn_flag_explanation global attribute(warn_flag)
• standard deviation of co2mv(co2mv_se)