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East Trout Lake - EC
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| Category |
Air sampling observation |
| Sampling Type |
continuous |
| Sampling Height/Depth |
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| Sampling and Analysis Frequency |
Hourly |
| Sampling Environment |
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| Measurement Method |
NDIR |
| Current status and history of Instruments |
NDIR |
| Description of Instruments |
Licor 6252 |
| Time Zone |
UTC |
| Data Period |
2005-08-01 - 2008-12-31 |
| Data Type |
hourly, daily, monthly |
| Parameter detail |
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| Other Descriptions for Sampling and Analyses |
The continuous measurement of CO2 at Fraserdale, Alert, Candle Lake and Sable Island follow the set of principles and protocols set by the WMO based on non-dispersive infrared (NDIR) methodology methodology [Trivett and Kohler, WMO Report No. 134].
A standardize protocol is applied at all stations making continuous measurments (implemented at Alert and Fraserdale in 2000). Implemented at the start of the programs at Candle Lake and Sable Island in 2003. The objectives of the new protocol are:
1) To increase the lifetime of our working standard tanks from ~9 months to ~ 4 years,
2) To reduce the number of levels in our central calibration hierarchical scheme from 6 to 3 levels,
3) To permit a larger atmospheric measurement range to be covered,
4) To provide final data in near real time,
5) To eliminate the time involved with reprocessing the historical data because of drifts in either calibration tanks or scale.
The specifics of the new measurement
procedure are as follows:
1) At each site, 11 standard tanks are used; 5 station tanks (~350, 365, 380,395 and 410 ppm), 4 working tanks (~355, 370, 385 and 400 ppm), one target tank (~365 ppm) and one zero tank (~340 ppm).
2) The 5 station tanks are calibrated approximately every 6 months against a set of 5 transfer standards that are transported between the sites and the central laboratory in Toronto.
3) The working and target tanks are automatically calibrated every 11 days against the 5 station tanks. The station tanks have a lifespan more than 20 years.
4) The target and zero tanks are passed through the analyzer for 5 minutes each at the top of every hour. The working tanks are sequentially passed through the analyzer (for 5 minutes each) every 5 hours after the hourly target and zero tanks have been passed through the system. The 5-hour time span of the working tanks results in a life span for these tanks of approximately 4 years. The target and zero tanks have life spans of ~9 and 3 months respectively.
A Campbell Scientific (Model CR21x) data logger is used to control the automated injection sequence and processes 5 minute averaged data records generated from the 1 second output signal voltages from the NDIR analyzer. The data logger also collects auxiliary data information on temperatures, pressures and flow rates. A local server collects the data from the logger and makes it available via FTP to the server at the in Toronto. |
| Scientific Aim |
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| Supporting Contributor(s) |
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| Last update |
2009-08-28 |
| Situation |
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This site is maintained by the Japan Meteorological Agency
in cooperation with the World Meteorological Organization
(Created : 2001/07/02 Modified : 2010/07/31)
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WMO World Data Centre for Greenhouse Gases
c/o Japan Meteorological Agency
1-3-4, Otemachi, Chiyoda-ku
Tokyo 100-8122, Japan
| Tel: |
+81-3-3287-3439 |
| Fax: |
+81-3-3211-4640 |
| E-mail: |
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WDCGG Data Submission and Dissemination Guide (PDF 1.2Mbyte)
WDCGG leaflet (PDF 2.7MByte, July 2008)