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The Atmospheric 222Rn database

EML's 222Rn analyzers, deployed at the Mauna Loa Observatory (MLO; operated under the auspices of the NOAA/ Climate Monitoring and Diagnostics Laboratory) and at Bermuda (at the Atmospheric/Ocean Chemistry Experiment Site at Tudor Hill, Bermuda), provide data used to determine air mass provenance, specifically, the timing of continentally-derived air transported to the mid-Atlantic and mid-Pacific. Additionally, the 222Rn data are used to better understand local meteorological effects, as well as providing the scientific community a rare database used to validate global transport models.

The databases can be viewed online if your browser supports tables, and can be downloaded in MS Excel 5.0 format or Adobe Acrobat PDF format. Each file contains one years data for one site. Concentrations are in mBq m-3, with times listed being the beginning of the sampling period. For the MLO site, data are analyzed on a half-hour period, whereas at the Bermuda site data are analyzed on an hourly basis.

For more information on the specifications and use of EML's 222Rn analyzer, see Hutter et al. (1995).

The results of the first international intercomparison of atmospheric 222Rn analyzers, including EML's analyzer, was published in the Journal of Geophysical Research (Collé et al.).

MS Excel 5.0 spreadsheets (in ZIP files):

Tables and PDF files:

If you do not have Adobe Acrobat Reader, click here to download it.

Site and Year: Adobe PDF file:
MLO, 1991 mlorn91.pdf
MLO, 1992 mlorn92.pdf
MLO, 1993 mlorn93.pdf
MLO, 1994 mlorn94.pdf
MLO, 1995 mlorn95.pdf
MLO, 1996 mlorn96.pdf
Bermuda, 1991 berrn91.pdf
Bermuda, 1992 berrn92.pdf
Bermuda, 1993 berrn93.pdf
Bermuda, 1994 berrn94.pdf
Bermuda, 1995 berrn95.pdf
Bermuda, 1996 berrn96.pdf



Collé, R., M. P. Unterweger, P. A. Hodge, J. M. R. Hutchinson, S. Whittlestone, G. Polian, B. Ardouin, J. G. Kay, J. P. Friend, B. W. Blomquist, W. Nadler, T. T. Dang, R. J. Larsen and A. R. Hutter. "An international intercomparison of marine atmospheric Rn 222 measurements in Bermuda". Journal of Geophysical Research, 100(D8):16617-16638, 1995.

Hutter, A. R., R. J. Larsen, H. Maring, J. T. Merrill. "222Rn at Bermuda and Mauna Loa: Local and Distant Sources". Journal of Radioanal. and Nuclear Chemistry, 193(2):309-318, 1995.


For more information about the Atmospheric 222Rn database,