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Ushuaia
-O3-
| Observation |
| Category |
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Air sampling observation |
| Situation |
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ongoing |
| Time zone |
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UTC |
| Sampling |
| Sampling height |
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24 |
| Description |
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continuous |
| Sampling and analysis frequency |
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Continuous |
| Sampling environment |
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The station is located in a coastal cliff at an altitude of 18 m above sea level, on a remote sub-Antarctic marine coast. Steady winds blow prevailing from the clean air sector (SW) down the Beagle Channel. The ground in the vicinity around the station is covered with pasture and bush.
The vegetation in the surrounding area is consisting mainly of shrub and southern beech (Nothofagus species) forest. |
| Description for sampling analysis |
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Intake height: 6 m above ground on top of the station building, 2 m above the roof.
Inlet/Manifold: 2x5 m t inch PFA tubing, from there connections CO and ozone instruments by t inch PFA tubing, length approx. 3 m for each instrument. Additional pump to increase flow rate.
Total flow rate 11 liter per minute with current set-up.Inlet-filter: Teflon inlet filter before analyzer, exchanged monthly.
Residence time in the sampling line: approx. 5 s |
| Instrument and Analysis |
| Measurement method |
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Light absorption analysis (UV) |
| Current status and history of instrument |
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Two TEI 49 ozone analyzers are running at the Ushuaia GAW station. They were running parallel using the same inlet. |
| Description of instrument |
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Thermo Environmental Instruments Inc.
Instrument model TEI 49 #47306-278 "O3-1" TEI 49 #47312-278 "O3-2"
internal ozone generator
Range 0-100 ppb
Analog output 0-10 V |
| Calibration |
| Current scale employed in the measurement |
: |
Absolute scale, ppb |
| Measurement calibration |
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System and performance audit conducted by WMO - IFU November 1994.
System and performance audit conducted by WMO - INM November 1997.
System and performance audit conducted by WMO - EMPA November 1998.
System and performance audit conducted by WMO - by the World Calibration Centre (WCC) for Surface Ozone, carbon Monoxide and Methane and QA/SAC Switzerland. November 2003.
Daily zero check.
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| Scale and calibration(treasability) |
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Absolute scale, ppb |
| Data Processing |
| Measurement unit |
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ppb |
| Data processing |
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Data processing is done at Ushuaia and consists of a weekly visual inspection of time series. The final data evaluation is done monthly. Invalid values (i.e. instrument maintenance) are flagged as
invalid data but are not removed from the database. A filter based on wind direction and velocity is applied to distinguish between “background” and “polluted” air masses.
We defined as baseline conditions:wind direction within 220-270wind velocity >= 5m/s
Data is show in 10 minutes averages. |
| Processing for averaging |
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| Data flag |
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| Data remarks |
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| Other Information |
| Scientific aim |
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| Reference |
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| submitted by Estacion VAG Ushuaia, Servicio Meteorologico Nacional - Gobierno de Tierra del Fuego |
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