论文标题
Dansgaard-Oeschger事件和千禧年级气候变化的模型，而无需外部强迫
A model for Dansgaard-Oeschger events and millennial-scale abrupt climate change without external forcing
论文作者
论文摘要
我们提出了一个概念模型，该模型会产生类似于Dansgaard-Oeschger事件的突然气候变化。在模型中，这些突然的气候变化不是由外部扰动触发的，而是通过海洋，大气和间歇性过程的复杂相互作用而在动态自洽的模型中触发的。突然的气候变化是在我们的模型中通过海冰覆盖的间歇性引起的。海洋由一个巨大的两个盒模型，由洛伦兹-84模型的大气和海冰覆盖，通过确定性添加剂和乘法噪声（CAM）过程的确定性近似。模型的关键动力成分是由确定性多尺度系统的随机限制和确定性均质化理论的最新结果给出的。确定性模型再现了实际冰核数据的统计特征，例如非高斯$α$稳定行为。 突然的千年气候变化的提议的机制仅取决于数量的存在，该数量在中间时间尺度上表现出间歇性动力学。我们认为是一种间歇性的海冰覆盖，在这种机制中，通过紧急大气噪声产生间歇性。但是，在拟议的框架内也可以制定其他机制，例如淡水流入。
We propose a conceptual model which generates abrupt climate changes akin to Dansgaard-Oeschger events. In the model these abrupt climate changes are not triggered by external perturbations but rather emerge in a dynamic self-consistent model through complex interactions of the ocean, the atmosphere and an intermittent process. The abrupt climate changes are caused in our model by intermittencies in the sea-ice cover. The ocean is represented by a Stommel two-box model, the atmosphere by a Lorenz-84 model and the sea-ice cover by a deterministic approximation of correlated additive and multiplicative noise (CAM) process. The key dynamical ingredients of the model are given by stochastic limits of deterministic multi-scale systems and recent results in deterministic homogenisation theory. The deterministic model reproduces statistical features of actual ice-core data such as non-Gaussian $α$-stable behaviour. The proposed mechanism for abrupt millenial-scale climate change only relies on the existence of a quantity, which exhibits intermittent dynamics on an intermediate time scale. We consider as a particular mechanism intermittent sea-ice cover where the intermittency is generated by emergent atmospheric noise. However, other mechanisms such as freshwater influxes may also be formulated within the proposed framework.
