Data quality assessment - parallel continuous mercury measurement at two levels of Tall tower Křešín, NAO Košetice, Czech Republic

0517522 - ÚVGZ 2020 PL eng A - Abstract
Vítková, Gabriela - Komínková, Kateřina - Szabó-Takács, Beáta - Čampulová, Martina - Hanuš, Jan - Holoubek, Ivan
Data quality assessment - parallel continuous mercury measurement at two levels of Tall tower Křešín, NAO Košetice, Czech Republic.
14th International Conference on Mercury as a Global Pollutant (ICMGP 2019) - abstract volume. Krakov: Targi w Krakowie Ltd., 2019 - (Pacyna, J.; Falandysz, J.; Golas, J.). s. 208-208
[14th International Conference on Mercury as a Global Pollutant (ICMGP 2019). 08.09.2019-13.09.2019, Krakov]
R&D Projects: GA MŠMT(CZ) LO1415; GA MŠMT(CZ) LM2015061
Institutional support: RVO:86652079
Keywords : tgm continuous measurement * tall tower * data quality * comparison measurement * qa/qc application and evaluation

The Tall tower Křešín u Pacova located at the National Atmospheric Observatory Košetice in the Czech Republic ensures measurements of total gaseous mercury (TGM) as a long term continuous observation at the background conditions. For nearly a year the two Tekran 2537B devices were measuring both at the ground level and since October 2013 they have been measuring parallely at the ground level and at the level of 240 meters. After more than six years of almost continuous operation these instruments will soon be exchanged for new ones. Data quality assessment has therefore been performed in order to revise old measurement and optimize future routines. Being a part of Global Mercury Observation System (GMOS) network measurement follows its standard operational procedures and the data are included in its database. Validation procedure consists of two steps: automatic processing, based on recorded instrumental parameters and on set thresholds, and manual processing, based on operator’s knowledge of situation and state of instrument. In some cases bad data can pass through the automatic processing without noticing. The decision about data quality is not easy to make. Using regular intercomparisons of two mentioned devices provides a general overview of the situation. It helps to decide about the data quality and whether the measured difference of two levels is caused by gradient of the Hg concentration in the air or by the instruments itselves. During last four years eight periods of parallel measurements at ground level were performed. For each period outputs of the two instruments were compared by using basic statistical tests and visualized in time to identify the change in deviation. Effect of various validation flags was then carefully investigated, in order to estimate how the disposition of device influence the accuracy of measurement.
Permanent Link: http://hdl.handle.net/11104/0302858