Key points are not available for this paper at this time.
AbstractIntra-ring differences of the 13C/12C ratio in tree rings are found to be very large in four Dutch trees. In some cases differences were measured over 4” ° δ13C. Even the 13C/12C ratio averaged over entire rings sometimes still exhibits abrupt jumps of over 1” ° in δ13C from year to year. Significant correlations of δ13C in tree rings with yearly average temperature and precipitation are found. Responses of the atmosphere to a 13C labelled input of CO2 are calculated in 3½ box perturbation model, consisting of an atmosphere, a biosphere, an oceanic mixed layer and a leak of the perturbation to the deep seas. The average 13C record obtained from the four trees is interpreted in terms of past biospheric growth and shrinkage by using the 3½ box model.
Tans et al. (Sun,) studied this question.