A box diffusion model to study the carbon dioxide exchange in nature

Reconstruction of the 14C Production Rate from Measured Relative Abundance

“…For the purpose of studying 14 C, production and radioactive decay are also included in box models. Free parameters in the Oeschger-Siegenthaler type box model (Oeschger et al 1974;Siegenthaler et al 1980) are the 14 C production rate Q, the air-sea exchange rate (expressed as turnover rate k), and the vertical eddy diffusion coefficient K, which combines ocean ventilation into a single parameter. Starting from the original representation (Oeschger et al 1974), a variety of box models have been developed which take into account subdivisions of the ocean reservoir and direct exchange between the deep ocean and the atmosphere at high latitudes.…”

“…Free parameters in the Oeschger-Siegenthaler type box model (Oeschger et al 1974;Siegenthaler et al 1980) are the 14 C production rate Q, the air-sea exchange rate (expressed as turnover rate k), and the vertical eddy diffusion coefficient K, which combines ocean ventilation into a single parameter. Starting from the original representation (Oeschger et al 1974), a variety of box models have been developed which take into account subdivisions of the ocean reservoir and direct exchange between the deep ocean and the atmosphere at high latitudes. These models have been run in prognostic mode for which the time series of parameter variations are prescribed, such as a reduction in ocean ventilation or sea-ice cover, and the response of the atmospheric ∆ 14 C level is obtained as output of the model.…”

The ~ 2400-year cycle in atmospheric radiocarbon concentration: bispectrum of <sup>14</sup><i>C</i> data over the last 8000 years

“…Variations in the atmospheric concentration of 14 C are the result of changes in the Earth's dipole moment (Elsasser et al, 1956;O'Brien, 1979;Lal, 1988), strengthening or weakening of solar activity (Stuiver and Quay, 1980;Bard et al, 1997) and parameters of radiocarbon exchange system (Oeschger et al, 1975;Siegenthaler et al, 1980;Stocker and Wright, 1996;Goslar et al, 1999). Variability of the 14 C Correspondence to: V. A. Dergachev (v.dergachev@pop.ioffe.rssi.ru) concentration is proved by experimental research, see (e.g.…”

Holocene megathermal abrupt environmental changes derived from 14C dating of a coral reef at Leizhou Peninsula, South China Sea

“…CRA's of the coral reef samples were converted to calendar ages using a calibration that incorporates variations of the 14 C concentration in the atmosphere and the marine reservoir effect [8][9][10][11]. This effect was estimated for the South China Sea to be DR ¼ À17 AE 17 14 C years [12] and was input to the calibration program Oxcal [13].…”