Sentences with phrase «isotopic ratio during»
Not exact matches
The scientists analyzed the samples» isotopic ratios — a telltale chemical signature of what the animals ate during their lifetimes.
http://www.sciencemag.org/
«THE stable carbon isotopic (13C / 12C) record of twentieth - century tree rings has been examined1 - 3 for evidence of the effects of the input of isotopically lighter fossil fuel CO2 (δ 13C ~ -25 ‰ relative to the primary PDB standard4), since the onset of major fossil fuel combustion during the mid-nineteenth century, on the 13C / 12C ratio of atmospheric CO2 (δ 13C ~ -7 ‰), which is assimilated by trees by photosynthesis.
In other words, if all of the terrestrial carbon today (in forests, animals, soils, etc.) were converted to carbon dioxide and returned to the global inorganic carbon pool, the change in the global carbon isotopic ratio would only be a third as big as that observed during the PETM!