Abstract Dissolved oxygen concentrations in the ocean are declining on a global scale. However, the impact of climate change on oxygen in shelf seas is not well understood. We investigate potential future changes in oxygen on the northwest European continental shelf under a business as usual greenhouse gas emissions scenario (Representative Concentration Pathway RCP8.5). Regions of the European shelf are thermally stratified from spring to autumn, which can cause oxygen depletion in sub-pycnocline waters. A transient climate-forced model simulation is used to study how the temperature, salinity and concentration of near bed dissolved oxygen change over the 21st century. In warming and freshening water, the oxygen concentration declines in all shelf regions. The climate change signal emerges first in salinity, then in temperature and finally in near bed oxygen. Regions that currently experience oxygen depletion (the eastern North Sea, Celtic Sea and Armorican shelf) become larger in the future scenario and oxygen depletion lasts longer. Solubility changes, caused by changes in temperature and salinity, are the dominant cause of reducing near bed oxygen concentrations in many regions. Until about 2040 the impact of solubility dominates over the effects of the evolving ecosystem. However, in the eastern North Sea by 2100, the effect of ecosystem change is generally larger than that of solubility. In the Armorican Shelf and Celtic Sea the ecosystem changes partially mitigate the oxygen decline caused by solubility changes. Over the 21st century the mean near bed oxygen concentration on the European shelf is projected to decrease by 6.3%, of which 73% is due to solubility changes and the remainder to changes in the ecosystem. For monthly minimum oxygen the decline is 7.7% with the solubility component being 50% of the total.

中文翻译：

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未来潜在气候情景下西北欧大陆架近床氧浓度的控制

摘要 在全球范围内，海洋中的溶解氧浓度正在下降。然而，气候变化对大陆架海域氧气的影响尚不清楚。我们调查了在照常营业的温室气体排放情景（代表性浓度途径 RCP8.5）下欧洲西北部大陆架上氧气的潜在未来变化。欧洲大陆架的区域从春季到秋季会发生热分层，这会导致次偏斜水域中的氧气耗尽。瞬态气候强迫模型模拟用于研究 21 世纪近床溶解氧的温度、盐度和浓度如何变化。在变暖和淡水中，所有大陆架区域的氧气浓度都会下降。气候变化信号首先出现在盐度上，然后是温度，最后是近床氧气。目前正在经历氧气耗尽的地区（北海东部、凯尔特海和阿莫里卡大陆架）在未来的情景中会变得更大，并且氧气耗尽的持续时间更长。由温度和盐度变化引起的溶解度变化是许多地区降低近床氧浓度的主要原因。直到 2040 年左右，溶解度的影响将超过不断演变的生态系统的影响。然而，到2100年，在北海东部，生态系统变化的影响普遍大于溶解度的影响。在 Armourican 大陆架和凯尔特海，生态系统的变化部分缓解了溶解度变化引起的氧气下降。在 21 世纪，欧洲大陆架上的平均近床氧浓度预计将下降 6.3%，其中 73% 是由于溶解度变化，其余是由于生态系统的变化。对于每月最低氧气量，下降为 7.7%，溶解度成分为总量的 50%。