资源环境科技发展态势分析平台

In a widely‐held conception, the biological carbon pump (BCP) is equal to the export of organic matter out of the euphotic zone. Using global ocean‐atmosphere model experiments we show that the change in export production is a poor measure of the biological pump’s feedback to the atmosphere. The change in global true oxygen utilization (TOU), an integrative measure of the imprint of the biological carbon pump on marine oxygen, however, is in good agreement with the net change in the biogenic air‐sea flux of oxygen. Since TOU correlates very well with apparent oxygen utilization (AOU) in our experiments, we propose to measure the change of AOU from data of global float programs to monitor the feedback of the BCP to the atmosphere. For the current ocean we estimate that BCP changes effect a CO₂ uptake by the ocean in the range of 0.07 to 0.14 GtC/yr.