Sensitivity of ocean carbon cycling to anthropogenic emissions

燃烧化石燃料和砍伐森林造成的碳排放导致大气中二氧化碳浓度增加，这反过来又导致辐射加热增加。当二氧化碳被排放到大气中时，很大一部分碳最初被海洋吸收，这减少了排放的直接辐射加热。最终，大气和海洋在几百到一千年后接近平衡状态。大气中残留的二氧化碳会导致长期的辐射加热。了解碳循环如何变化的问题通常通过整合大型复杂的气候模型来解决。虽然这些气候模式是有用的，但我们希望采取不同的方法，重点关注大气和海洋的长期平衡状态。在这种平衡状态下，我们预测，碳排放导致大气中二氧化碳浓度的指数增加和长期辐射加热的线性增加。如果我们所有的传统碳储量都被利用，那么长期的辐射加热是目前碳排放增加的辐射加热的4倍。我们的目标是在一个包括碳和温度反馈的气候模型中测试这一预测。以类似的方式，我们的目标是比较我们对海洋分层和酸度增加将如何影响碳循环的预测。我们的长期平衡解决方案将与代表海洋和整个地球系统中碳循环的气候模型进行比较。这种比较将提供对碳系统如何运作的深入了解，以及政策制定者在比较不同的碳排放情景时需要考虑的气候变化的长期背景。

Carbon emissions from burning of fossil fuels and deforestation have led to increasing concentrations of carbon dioxide in the atmosphere, which in turn lead to an increase in radiative heating. When the carbon dioxide is emitted into the atmosphere, a significant fraction of the carbon is initially taken up by the oceans, which reduces the immediate radiative heating from the emissions. Eventually, the atmosphere and ocean approach an equilibrium state after several hundred to a thousand years. The carbon dioxide remaining within the atmosphere leads to a long-term radiative heating. The problem of understanding how the carbon cycle varies is usually addressed by integrating large, complicated climate models. While these climate models are useful, we wish to adopt a different approach focussing on a long-term equilibrium state for the atmosphere and ocean. At this equilibrium state, we predict that carbon emissions lead to an exponential increase in the atmospheric concentration of carbon dioxide and a linear increase in the long-term radiative heating. If all our conventional carbon reserves are utilised, then the longterm radiative heating is 4 times larger than the present-day increase in radiative heating from carbon emissions. We aim to test this prediction in a climate model including carbon and temperature feedbacks. In a similar manner, we aim to compare our predictions of how increasing ocean stratification and acidity will affect the carbon cycle. Our longterm equilibrium solutions will be compared with climate models representing the cycling of carbon in the ocean and the whole Earth System. This comparison will provide insight into how the carbon system operates and a longterm context for climate change which policy makers need to consider when comparing different carbon emission scenarios.