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Radiocarbon method in monitoring of fossil fuel emission

Rakowski A. Z.

Geochronometria

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2011

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Vol. 38, no. 4

314-324

EN

The traditional radiocarbon method widely used in archaeology and geology for chronological purposes can also be used in environmental studies. Combustion of fossil fuels like coal, natural gas, petroleum, etc., in industrial and/or heavily urbanized areas, has increased the concentration of carbon dioxide in the atmosphere. The addition of fossil carbon caused changes of carbon isotopic composition, in particular, a definite decrease of 14C concentration in atmospheric CO2 and other car-bon reservoirs (ocean and terrestrial biosphere), known as the Suess effect. Tree rings, leaves, as well as other annual growing plants reflected the changes of radiocarbon concentration in the atmosphere due to processes of photosynthesis and assimilation of carbon from the air. By measuring radiocarbon concentration directly in atmospheric CO2 samples and/or biospheric material growing in industrial and/or highly urbanized areas where high emission of dead carbon is expected, it is possible to estimate the total emission of dead CO2 . Based on equations of mass balance for CO2 concentration, stable isotopic composition of carbon and radiocarbon concentration it is possible to calculate CO2 concentration associated with fossil fuel emission into the atmosphere. The procedure use differences between the radiocarbon concentration and stable isotope composition of carbon observed in clean areas and industrial or/and highly urbanized areas.

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Radiocarbon concentration in urban area

Rakowski A. Z., Kuc T., Nakamura T., Pazdur A.

Geochronometria

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2005

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Vol. 24

63-68

EN

Radiocarbon concentration has decreased in recent years due to the exchange of 14CO2 between the atmosphere and the oceans, but also due to 12CO2 emission from burning fossil fuels. This second phenomenon known as Suess effect can be observed in the highly industrialized and/or urban areas. New data of radiocarbon concentration in tree rings from Nagoya (Central Japan) and Kraków (Poland), which covered last 20 years, were obtained recently. These data were used to find the relationship between the radiocarbon concentrations in atmosphere and biosphere. Additionally, data of radiocarbon concentration in atmospheric CO2 in Kraków were compared with those derived from annual tree rings, to calculate the time of CO2 uptake for pine trees in this region. These data show that radiocarbon concentration of the CO2 in .urban air. is systematically lower than that in "clean air". Data of radiocarbon concentration were fitted by exponential and linear functions to calculate the time of exchange and predict the future level. Using data of carbon dioxide and radiocarbon concentration from Schauinsland fossil component Cf in carbon dioxide concentration level was calculated in Nagoya and Kraków.

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Radiocarbon concentration measurements in contemporary tree rings from Upper Silesia

Rakowski A. Z., Pawełczyk S., Pazdur A.

Geochronometria

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2000

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Vol. 18

19-22

EN

Upper Silesia is an example of the most industrially changed natural environment in Poland. This state is a consequence of mining development in the last 150 years as well as accumulation of a number of towns and industrial companies with high impact to the environment. A decrease of radiocarbon concentration resulted from the "Suess effect" was observed in the Upper Silesia region. Estimation of this effect, on the basis of carbon isotope analysis in annual tree rings collected from trees growing in the region considered, has been carried out.