挪威极地研究所 Sumata, Hiroshi小组报道了北冰洋海冰厚度的机制转移。相关论文于2023年3月15日发表在《自然》杂志上。

研究人员展示了2007年北极海冰的状况变化，从较厚和变形转变为较薄且更均匀的冰盖。过去三十年以来，他们对弗拉姆海峡海冰的持续监测揭示了这种变化。漂移之后，厚而变形的冰的比例下降了一半，至今仍未恢复。在这一转变之前，北极海盆的海冰停留时间分两步缩短，第一次始于2005年，随后是2007年。该研究团队证明了一个描述动态海冰增厚随机过程的简单模型，解释了由于停留时间的减少而观测到的冰厚度变化。研究强调了气候变化通过减少北极海冰的停留时间，对北极海冰产生的持久影响，以及气候变化与相邻边缘海和大陆架中海洋-海冰耦合过程的联系。

据介绍，气候变化的表现通常表现为物理或生物地球化学性质的逐渐变化。然而，气候系统的组成部分可以显示从一种状态到另一种状态的逐步转变，这是系统对变化的作用力的非线性响应。

附：英文原文

Title: Regime shift in Arctic Ocean sea ice thickness

Author: Sumata, Hiroshi, de Steur, Laura, Divine, Dmitry V., Granskog, Mats A., Gerland, Sebastian

Issue&Volume: 2023-03-15

Abstract: Manifestations of climate change are often shown as gradual changes in physical or biogeochemical properties. Components of the climate system, however, can show stepwise shifts from one regime to another, as a nonlinear response of the system to a changing forcing. Here we show that the Arctic sea ice regime shifted in 2007 from thicker and deformed to thinner and more uniform ice cover. Continuous sea ice monitoring in the Fram Strait over the last three decades revealed the shift. After the shift, the fraction of thick and deformed ice dropped by half and has not recovered to date. The timing of the shift was preceded by a two-step reduction in residence time of sea ice in the Arctic Basin, initiated first in 2005 and followed by 2007. We demonstrate that a simple model describing the stochastic process of dynamic sea ice thickening explains the observed ice thickness changes as a result of the reduced residence time. Our study highlights the long-lasting impact of climate change on the Arctic sea ice through reduced residence time and its connection to the coupled ocean–sea ice processes in the adjacent marginal seas and shelves of the Arctic Ocean.

DOI: 10.1038/s41586-022-05686-x

Source: https://www.nature.com/articles/s41586-022-05686-x