No.8

Introduction
Data Policy
Data
Documentation
Contact Information



Krvavec

-O3-

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Station Contact Person(s) Observation Data and Quick Plot

Observation
Category : Air sampling observation
Situation : ongoing
Time zone : Local time +1


Sampling
Sampling height : 10
Description : continuous
Sampling and analysis frequency : Continuous air flow of 0.745 litres per minute through the ozone instrument and data are analysed every 60 seconds.
Sampling environment : Krvavec monitoring site is situated at the altitude of 1600 m, surrounded mostly by short grass, and under 1600 m partly with coniferous forest. Surrounding slopes and peaks are rocky (limestone). It is located cca. 30 km north of Ljubljana city on mountain crest on the edge of eastern Alps (Kamniško Savinjske alpe – mountain crest with peaks reaching 1500 to 2500 m). Monitoringt site lies above the cold surface air layer, which occurs frequently over the Ljubljana basin during wintertime. Sometimes during anticyclonal situations the inversion layer may rise higher so that the monitoring site lies inside the inversion layer. In heating and skiing period of the year during special weather conditions (weak South to South-East wind) the skiing center and small villages lying beneath Krvavec may slightly contribute to the local air pollution.
Description for sampling analysis : UV-absorption
Automatic sampling
Air is sampled through the glass tube at 10 m height and into the instrument.


Instrument and Analysis
Measurement method : Light absorption analysis (UV)
Current status and history of instrument : 10.09.08 - present; Model 49C; Serial nr.: 54544-300, ID 374; TEI Inc.
Description of instrument : Custom ranges:
Range: 50; 100; 200; 500; 1000; 2000; 5000 ppb
Zero noise: 0.5 ppb RMS
Lower detectable limit: 1.0 ppb
Response time: 20 seconds (0-95%)
LAG time: 10 seconds
Precision: 1ppb
Linearity: ±1 % Fullscale
Flow rate: 1-3 liters/min


Calibration
Current scale employed in the measurement : Observers standard scale, traceable to CHMI
Measurement calibration : Gases from the Internal Zero Span System are introduced every 24,5 hours (30, 50, 80, 100). The span gas from the working standard instrument is introduced once every three month on the spot.

Instrument is calibrated in accredited calibration laboratory once per year. The span gas is introduced at zero level and 4 spans. In addition also ‘type approval’ tests (short term drift, response time, linearity and repeatability) are also performed annually.

The mole fractions are determined by the linear regression line from zero level and the 4 spans.
Scale and calibration(treasability) : A calibration laboratory’s primary/reference standard UV photometer ozone generator (Thermo Environmental Instruments 49C PS) is calibrated at CHMI every year and therefore traceable to international level.

The transfer standard ozone generator (MLU) is calibrated by Accredited Calibration laboratory once a year against primary standard.

The instrument is regularly calibrated 4 times per year:
- against primary standard once in accredited laboratory,
and the rest
- against transfer standard on field.

Intercomparison in Evaluation of the Laboratory Comparison
Exercise for SO2, CO, O3, NO and NO2 is attended every 2 years.


Data Processing
Measurement unit : ppb
Data processing : The raw data from the instrument are collected on the local PC, and stored in the system as one minute raw data. In the 1st level automatic control takes place and all invalid data are flagged. Half an hour data is calculated from valid minute data and transferred to the database on ARSO where 2nd level control and flagging is performed by responsible person. All invalid half an hour data are eliminated. Valid data coverage must be at least 75%.
Processing for averaging : Processing for Hourly Data:
Hourly data are generated as arithmetic means of the checked valid half an hour data.
Processing for Daily Data:
Daily data are generated as arithmetic means of valid hourly data. Valid data coverage must be at least 75%.
Processing for Monthly Data:
Monthly O3 data were generated as aritmethic means of the valid daily data untill 2010. Valid data coverage must be at least 75%.

Monthly O3 data are generated as aritmethic means of the valid hourly data from 2011 on. Valid data coverage must be at least 75%.
Data flag : Flags According to EEA/DEM (European Environment Agency/Data Exchange Module) were used until the end of the year 2002.

EMEP flags have been used from the beginning of the year 2003 List of flags is available on EMEP homepage / CCC / Data submission / List of flags used in EMEP data base (http://www.nilu.no/projects/ccc/submission.html).
Data remarks :


Other Information
Scientific aim : To provide data for research and study to reveal long term trends.
Reference : EMEP manual for sampling and chemical analysis (EMEP/CCC-Report 1/95, Reference: O-7726, Norwegian Institute for Air Research, Date: March 1996, Revision: November 2001) (http://www.nilu.no/projects/ccc/manual/index.html).


submitted by Slovenian Environment Agency



The WDCGG is operated by the Japan Meteorological Agency
in collaboration with the World Meteorological Organization