Natural and artificial radionuclides in the tropospheric and lower stratospheric air over Poland

• Autorzy: Kownacka L.
• Konferencja: Proceedings of the Third International Meeting on Low-Level Air Radioactivity Monitoring, 25-29 September, 2000, Dabrowno near Nidzica, Poland
• Języki publikacji: EN

Abstrakty

EN

The high altitude aircraft sampling of aerosols have been carried out at four to seven levels up to 15 km over Poland from 1973 to 1998, and 117 vertical concentration profiles of natural radionuclides and fission products were determined. It was found that the atmospheric concentrations of 226Ra increased after large volcanic eruptions. The vertical concentrations profile of 226Ra had a characteristic quasi-parabolic distribution, with the highest concentrations near the ground level and in the stratosphere. Concentrations of 210Pb had a more homogeneous vertical distribution, due to the quiescent ascent of its gaseous 222Rn precursor from the ground. Vertical concentrations of fission products revealed different types of profiles. After nuclear explosions, the highest concentrations were observed in the stratosphere. The Chernobyl accident reversed the aerial vertical profiles; the main source was near the ground level, but part of the radioactive debris entered also the lower stratosphere. Because of resuspension, the stratospheric residence time of radiocesium from the Chernobyl accident was about three times longer than that of the fallout from nuclear explosions. The resuspension effects and the atmospheric mass transport in the boundary layers are also responsible for the increased concentrations of radiocesium at 1 km altitude observed since 1987 in the situations of atmospheric mass advection from the highly contaminated Chernobyl region.

Słowa kluczowe

EN

atmospheric radioactivity; Chernobyl; nuclear tests; stratosphere; transport in the atmosphere; troposphere

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2001
• Tom: Vol. 46, nr 4
• Strony: 175--177
• Opis fizyczny: Bibliogr. 7 poz., rys.

Twórcy

autor

Kownacka L.

• Department of Radiation Hygiene, Central Laboratory for Radiological Protection, 7, Konwaliowa Str., 03-194 Warsaw, Poland, Tel.: [phone], Fax: [phone],

Bibliografia

• 1. Bhandari N, Lal D, Rama S (1970) Vertical structure of the troposphere as revealed by radioactive studies. J Geophys Res 75:2974–2980
• 2. Junge C E, Chaggon CW, Manson J E (1961) A world-wide stratospheric aerosol layer. Science 133:1478–1479
• 3. Kownacka L (1980) Vertical distribution of fission products, 226Ra and Pb in the atmosphere. Report INR 1895/IA/D/A. Institute of Nuclear Research, Warsaw
• 4. Kownacka L, Jaworowski Z, Suplińska M (1990) Vertical distribution and flows of lead and natural radionuclides in the atmosphere. Sci Total Environ 91:199–221
• 5. Kownacka L, Jaworowski Z (1994) Nuclear weapon and Chernobyl debris in the troposphere and lower stratosphere. Sci Total Environ 144:201–215
• 6. Kownacka L, Borkowski J L (1996) Changes in the vertical distribution of fission products over Poland during the period 1973–1994. Acta Geophys Pol 44:43–59
• 7. Kownacka L, Jaworowski Z, Zając B (1999) Measurement of concentrations of 7Be, 90Sr, 134,137Cs, 210Pb and 226Ra in the tropospheric and lower stratospheric air in 1997 and 1998. Report CLOR no. 138. Central Laboratory for Radiological Protection, Warsaw