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Updated: Sep 30, 2025

A Low-Cost Method of Measuring the In Situ Primary Productivity of Periphyton Communities of Lentic Waters
Published on: December 16, 2022
Global biosphere primary productivity changes during the past eight glacial cycles
Ji-Woong Yang1, Margaux Brandon1,2, Amaëlle Landais1
1Laboratoire des Sciences du Climat et de l'Environnement/Institut Pierre-Simon Laplace, Université Paris Saclay/CEA/CNRS/UVSQ, Gif-sur-Yvette, France.
Abstract:
Global biosphere productivity is the largest uptake flux of atmospheric carbon dioxide (CO2), and it plays an important role in past and future carbon cycles. However, global estimation of biosphere productivity remains a challenge. Using the ancient air enclosed in polar ice cores, we present the first 800,000-year record of triple isotopic ratios of atmospheric oxygen, which reflects past global biosphere productivity. We observe that global biosphere productivity in the past eight glacial intervals was lower than that in the preindustrial era and that, in most cases, it starts to increase millennia before deglaciations. Both variations occur concomitantly with CO2 changes, implying a dominant control of CO2 on global biosphere productivity that supports a pervasive negative feedback under the glacial climate.
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