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Zugspitze / Schneefernerhaus
-PAN-
Observation |
Category |
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Air sampling observation |
Situation |
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ongoing |
Time zone |
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Local time +1 |
Sampling |
Sampling height |
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Description |
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continuous |
Sampling and analysis frequency |
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quasi continuous. One chromatogram every 10 min |
Sampling environment |
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Description for sampling analysis |
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Instrument and Analysis |
Measurement method |
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Gas Chromatography (ECD) |
Current status and history of instrument |
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GC/ECD unit with calibration unit for calibration and measurement of PAN |
Description of instrument |
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Calibration |
Current scale employed in the measurement |
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Measurement calibration |
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PAN is calibrated by use of acetone photolysis with UV source followed by gas phase titration with NO. For that, the data refer to NO standard gas in cylinders. The NO standards refer to the German national normal which is provided by the unit of the Federal Environment Agency which also operates the GAW Station Zugspitze platform. Via BIPM, France, (http://www.bipm.org/) NO Standards are adjusted with the NO NIST scale, USA.
Calibration gas: 5 ppm V NO in Nitrogen gas N2 5.0. Calibrations are carried out weekly. |
Scale and calibration(treasability) |
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Data Processing |
Measurement unit |
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ppt |
Data processing |
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Processing for averaging |
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Processing for Hourly Data: The data acquisition system provides one chromatogram every 10 minutes. Chromatogram data are plotted, tested, corrected in case retention times show variations and reprocessed if required with a standardized spreadsheet and programmed procedures.
By the use of this calibrated data are produced.
Invalid data caused by local impact, malfunction or other effects are detected by comparison/ correlation with other trace substances and meteorological data and with information from the station logbook and then are rejected. 30 min mean values are generated by calculating the arithmetic mean of the remaining data with more than 2/3 of all data. For reporting to WDCGG hourly mean values are calculated from these half hourly data.
Processing for Daily Data: Daily: Take the arithmetic mean of selected half hourly data with the number of data more than 31. Processing for Monthly Data: Monthly: Take the arithmetic mean of selected half hourly data with the number of data more than 960. |
Data flag |
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Hourly
0: valid value
3: missing value due to calibration
6: missing
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Data remarks |
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Other Information |
Scientific aim |
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To provide reliable data for research to reveal long term trends of air pollution, long distance transport and climate change in Central Europe. |
Reference |
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“Qualitätssicherungs-Handbuch des UBA-Messnetzes”, UBA Texte 28/04, (Federal Environmental Agency), Dr. Klaus Nienerowski, Umweltbundesamt, Berlin, Juni 2004 |
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submitted by Federal Environmental Agency Germany |
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