Analysis of extreme beryllium-7 specific activities in surface air
Аутори
Ajtić, JelenaDjurdjević, Vladimir
Sarvan, Darko
Brattich, Erika
Hernández-Ceballos, Miguel Angel
Конференцијски прилог (Објављена верзија)
Метаподаци
Приказ свих података о документуАпстракт
The maxima in a large dataset of the beryllium-7 specific activities measured in surface air in
Helsinki, Finland, over 25 years (1987-2011), are analysed. The measurements at this station were
performed with a varying temporal resolution: weekly until 1999, and daily, or once in two days,
in the subsequent years, with a final dataset consisting of more than 4000 measurements. These
data are stored by the online Radioactivity Environmental Monitoring (REM) Database.
The beryllium-7 extremes in this dataset are defined as events with the beryllium-7 specific
activity above the 95thpercentile, or in other words, as the maximum 5 % of the measured values.
Specifically, for the Helsinki data set, this threshold is 4.82·10-3 Bq m-3. The beryllium-7 specific
activity in Helsinki shows a seasonal pattern with the monthly means above 2.00·10-3 Bq m-3
during the warm season (April–September), and below 2.00·10-3 Bq m-3during the cold season
(October–March). The analysis of the extreme...s shows that 90 % occurred in the warm season,
and the remaining 10 % in the cold season. The occurrence of the extreme beryllium-7 events
during the cold season is therefore of particular interest, and these “cold extremes” are analysed
in more detail.
Amongst the cold extremes, three extreme episodes are identified. These episodes, which
occurred in March 1999, February 2003 and February 2005, show extremely high berrylium-7
specific activities measured over several consecutive days. Potential vorticity and surface
temperature maps over Europe are investigated in attempt to find underlying mechanisms that
cause high concentrations of beryllium-7 in surface air during the cold season.
Кључне речи:
beryllium-7 / specific activities / surface airИзвор:
Book of Abstracts of the Fourth International Conference on Radiation and Applications in Various Fields of Research, May 23–27, 2016, Niš, Serbia, 2016, 411-411Издавач:
- Niš : University, Faculty of Electronic Engineering
Колекције
Институција/група
Fakultet veterinarske medicineTY - CONF AU - Ajtić, Jelena AU - Djurdjević, Vladimir AU - Sarvan, Darko AU - Brattich, Erika AU - Hernández-Ceballos, Miguel Angel PY - 2016 UR - https://vet-erinar.vet.bg.ac.rs/handle/123456789/2365 AB - The maxima in a large dataset of the beryllium-7 specific activities measured in surface air in Helsinki, Finland, over 25 years (1987-2011), are analysed. The measurements at this station were performed with a varying temporal resolution: weekly until 1999, and daily, or once in two days, in the subsequent years, with a final dataset consisting of more than 4000 measurements. These data are stored by the online Radioactivity Environmental Monitoring (REM) Database. The beryllium-7 extremes in this dataset are defined as events with the beryllium-7 specific activity above the 95thpercentile, or in other words, as the maximum 5 % of the measured values. Specifically, for the Helsinki data set, this threshold is 4.82·10-3 Bq m-3. The beryllium-7 specific activity in Helsinki shows a seasonal pattern with the monthly means above 2.00·10-3 Bq m-3 during the warm season (April–September), and below 2.00·10-3 Bq m-3during the cold season (October–March). The analysis of the extremes shows that 90 % occurred in the warm season, and the remaining 10 % in the cold season. The occurrence of the extreme beryllium-7 events during the cold season is therefore of particular interest, and these “cold extremes” are analysed in more detail. Amongst the cold extremes, three extreme episodes are identified. These episodes, which occurred in March 1999, February 2003 and February 2005, show extremely high berrylium-7 specific activities measured over several consecutive days. Potential vorticity and surface temperature maps over Europe are investigated in attempt to find underlying mechanisms that cause high concentrations of beryllium-7 in surface air during the cold season. PB - Niš : University, Faculty of Electronic Engineering C3 - Book of Abstracts of the Fourth International Conference on Radiation and Applications in Various Fields of Research, May 23–27, 2016, Niš, Serbia T1 - Analysis of extreme beryllium-7 specific activities in surface air SP - 411 EP - 411 UR - https://hdl.handle.net/21.15107/rcub_veterinar_2365 ER -
@conference{ author = "Ajtić, Jelena and Djurdjević, Vladimir and Sarvan, Darko and Brattich, Erika and Hernández-Ceballos, Miguel Angel", year = "2016", abstract = "The maxima in a large dataset of the beryllium-7 specific activities measured in surface air in Helsinki, Finland, over 25 years (1987-2011), are analysed. The measurements at this station were performed with a varying temporal resolution: weekly until 1999, and daily, or once in two days, in the subsequent years, with a final dataset consisting of more than 4000 measurements. These data are stored by the online Radioactivity Environmental Monitoring (REM) Database. The beryllium-7 extremes in this dataset are defined as events with the beryllium-7 specific activity above the 95thpercentile, or in other words, as the maximum 5 % of the measured values. Specifically, for the Helsinki data set, this threshold is 4.82·10-3 Bq m-3. The beryllium-7 specific activity in Helsinki shows a seasonal pattern with the monthly means above 2.00·10-3 Bq m-3 during the warm season (April–September), and below 2.00·10-3 Bq m-3during the cold season (October–March). The analysis of the extremes shows that 90 % occurred in the warm season, and the remaining 10 % in the cold season. The occurrence of the extreme beryllium-7 events during the cold season is therefore of particular interest, and these “cold extremes” are analysed in more detail. Amongst the cold extremes, three extreme episodes are identified. These episodes, which occurred in March 1999, February 2003 and February 2005, show extremely high berrylium-7 specific activities measured over several consecutive days. Potential vorticity and surface temperature maps over Europe are investigated in attempt to find underlying mechanisms that cause high concentrations of beryllium-7 in surface air during the cold season.", publisher = "Niš : University, Faculty of Electronic Engineering", journal = "Book of Abstracts of the Fourth International Conference on Radiation and Applications in Various Fields of Research, May 23–27, 2016, Niš, Serbia", title = "Analysis of extreme beryllium-7 specific activities in surface air", pages = "411-411", url = "https://hdl.handle.net/21.15107/rcub_veterinar_2365" }
Ajtić, J., Djurdjević, V., Sarvan, D., Brattich, E.,& Hernández-Ceballos, M. A.. (2016). Analysis of extreme beryllium-7 specific activities in surface air. in Book of Abstracts of the Fourth International Conference on Radiation and Applications in Various Fields of Research, May 23–27, 2016, Niš, Serbia Niš : University, Faculty of Electronic Engineering., 411-411. https://hdl.handle.net/21.15107/rcub_veterinar_2365
Ajtić J, Djurdjević V, Sarvan D, Brattich E, Hernández-Ceballos MA. Analysis of extreme beryllium-7 specific activities in surface air. in Book of Abstracts of the Fourth International Conference on Radiation and Applications in Various Fields of Research, May 23–27, 2016, Niš, Serbia. 2016;:411-411. https://hdl.handle.net/21.15107/rcub_veterinar_2365 .
Ajtić, Jelena, Djurdjević, Vladimir, Sarvan, Darko, Brattich, Erika, Hernández-Ceballos, Miguel Angel, "Analysis of extreme beryllium-7 specific activities in surface air" in Book of Abstracts of the Fourth International Conference on Radiation and Applications in Various Fields of Research, May 23–27, 2016, Niš, Serbia (2016):411-411, https://hdl.handle.net/21.15107/rcub_veterinar_2365 .