Comparison of one- and two-filter detectors for atmospheric <sup>222</sup>Rn measurements under various meteorological conditions

Abstract

Abstract. Parallel monitoring of 222 Rn and its short-lived progeny ( 218 Po and 214 Pb) were carried out from November 2007 to April 2008 close to the top of the Schauinsland mountain, partly covered with forest, in South-West Germany. Samples were aspired from the same location at 2.5 m above ground level. We measured 222 Rn with a dual flow loop, two-filter detector and its short-lived progeny with a one-filter detector. A reference sector for events, facing a steep valley and dominated by pasture, was used to minimize differences between 222 Rn and progeny-derived 222 Rn activity concentrations. In the two major wind sectors covered by forest to a distance between 60 m and 80 m towards the station progeny-derived 222 Rn activity concentration was on average equal to 87% (without precipitation) and 74% (with precipitation) of 222 Rn activity concentration. The observations show that most of the time both detector types follow the same pattern. Still, there is no single disequilibrium factor that could be used to exactly transform short-lived progeny to 222 Rn activity concentration under all meteorological conditions.

Three years of semicontinuous greenhouse gas measurements at the Puy de Dôme station (central France)

“…of 1.15 ± 0.14. This value was independently confirmed by Xia et al (2010). The Puy de Dôme station and the Schauinsland station are two medium-elevation mountain stations, having the same geographical environment.…”

Surface-to-mountaintop transport characterised by radon observations at the Jungfraujoch

“…The instruments are of the twofilter dual flow loop design, with a delay chamber of 400 L to remove thoron and a radon detection chamber of 750 L (Whittlestone and Zahorowski, 1998). This design eliminates an uncertainty inherent to progeny detectors (Xia et al, 2010) but means that the detectors are large and have a relatively slow response time.…”

Analysis of ground‐based 222Rn measurements over Spain: Filling the gap in southwestern Europe

“…To deal with the above mentioned research issues, high‐quality 222 Rn concentrations and flux observations are needed with high spatial resolution. Several worldwide monitoring networks of GHGs and air quality are already performing atmospheric 222 Rn gas measurements at different heights from the ground and using different measurement techniques [ Whittlestone and Zahorowski , ; Levin et al ., ; Zahorowski et al ., ; Xia et al ., ; Grossi et al ., ; Chambers et al ., , , ]. Nevertheless, there is still a huge lack of data in southern Europe and, more generally, over the Mediterranean region.…”