Impact of atmospheric and terrestrial CO2 feedbacks on fertilization-induced marine carbon uptake
Impact of atmospheric and terrestrial CO2 feedbacks on fertilization-induced marine carbon uptake
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大气和陆地二氧化碳反馈对受精引起的海洋碳吸收的影响
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
A. Oschlies
中科院分区：
文献类型：
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作者：
A. Oschlies
海洋CO2吸收对海洋生物碳泵变化的敏感性，例如自然或有目的的海洋施肥所带来的变化，已经通过采用数值海洋地球化学海洋模型的研究反复进行了研究。这里表明，这种以海洋为中心的研究的结果是非常敏感的假设作出的反应的碳库的大气侧的海面。所作的假设包括规定的大气pCO 2，一个与海洋交换碳但不与陆地生物圈交换碳的交互式大气CO2库，以及一个与海洋和陆地碳库交换碳的交互式大气。这些假设对模拟的年度至千年海洋碳吸收的影响进行了研究，假设增加生物泵的C：N比和理想化的增强浮游植物的生长。与交互式大气模拟相比，使用规定的大气pCO 2高估了海洋CO2吸收对生物泵变化的敏感性，在年度，十年，百年和千年时间尺度上分别约为2%，25%，100%和>500%。在相互作用的大气下，海洋碳吸收的效率较小，这是由于当大气CO2减少时发生的CO2的反向通量。在大气-海洋模型系统中添加交互式陆地碳库对年时间尺度的影响很小，但对于C4 MIP模型中间范围内陆地碳储存的pCO 2敏感性，在十年、百年和千年时间尺度上分别将模拟的施肥诱导的海洋碳吸收增加约4%、50%和100%（Friedlingstein等人，2006年）。由于这种敏感性，自然或有目的的海洋肥化所引起的海洋碳吸收的很大一部分在几十年以上的时间尺度上不是来自大气，而是来自陆地生物圈。
The sensitivity of oceanic CO2 uptake to alterations in the marine biological carbon pump, such as brought about by natural or purposeful ocean fertilization, has repeatedly been investigated by studies employing numerical biogeochemical ocean models. It is shown here that the results of such ocean-centered studies are very sensitive to the assumption made about the response of the carbon reservoirs on the atmospheric side of the sea surface. Assumptions made include prescribed atmospheric pCO2, an interactive atmospheric CO2 pool exchanging carbon with the ocean but not with the terrestrial biosphere, and an interactive atmosphere that exchanges carbon with both oceanic and terrestrial carbon pools. The impact of these assumptions on simulated annual to millennial oceanic carbon uptake is investigated for a hypothetical increase in the C:N ratio of the biological pump and for an idealized enhancement of phytoplankton growth. Compared to simulations with interactive atmosphere, using prescribed atmospheric pCO2 overestimates the sensitivity of the oceanic CO2 uptake to changes in the biological pump, by about 2%, 25%, 100%, and >500% on annual, decadal, centennial, and millennial timescales, respectively. The smaller efficiency of the oceanic carbon uptake under an interactive atmosphere is due to the back flux of CO2 that occurs when atmospheric CO2 is reduced. Adding an interactive terrestrial carbon pool to the atmosphere-ocean model system has a small effect on annual timescales, but increases the simulated fertilization-induced oceanic carbon uptake by about 4%, 50%, and 100% on decadal, centennial, and millennial timescales, respectively, for pCO2 sensitivities of the terrestrial carbon storage in the middle range of the C4MIP models (Friedlingstein et al., 2006). For such sensitivities, a substantial fraction of oceanic carbon uptake induced by natural or purposeful ocean fertilization originates, on timescales longer than decades, not from the atmosphere but from the terrestrial biosphere.