Scripps Institution of Oceanography, University of California San Diego, San Diego, CA, USA.
University of Alaska Fairbanks, Fairbanks, Alaska, USA.
Nat Commun. 2021 Apr 23;12(1):2418. doi: 10.1038/s41467-021-22505-5.
Unprecedented quantities of heat are entering the Pacific sector of the Arctic Ocean through Bering Strait, particularly during summer months. Though some heat is lost to the atmosphere during autumn cooling, a significant fraction of the incoming warm, salty water subducts (dives beneath) below a cooler fresher layer of near-surface water, subsequently extending hundreds of kilometers into the Beaufort Gyre. Upward turbulent mixing of these sub-surface pockets of heat is likely accelerating sea ice melt in the region. This Pacific-origin water brings both heat and unique biogeochemical properties, contributing to a changing Arctic ecosystem. However, our ability to understand or forecast the role of this incoming water mass has been hampered by lack of understanding of the physical processes controlling subduction and evolution of this this warm water. Crucially, the processes seen here occur at small horizontal scales not resolved by regional forecast models or climate simulations; new parameterizations must be developed that accurately represent the physics. Here we present novel high resolution observations showing the detailed process of subduction and initial evolution of warm Pacific-origin water in the southern Beaufort Gyre.
通过白令海峡，前所未有的大量热量正进入北极海的太平洋扇区，尤其是在夏季。尽管一些热量在秋季冷却时会散失到大气中，但相当一部分传入的温暖、咸水会潜到较冷、更新鲜的近地表水层之下，随后延伸数百公里进入波弗特环流。这些次表层热口袋的向上湍动混合可能正在加速该地区的海冰融化。这种来自太平洋的水既带来热量，也带来独特的生物地球化学特性，促成了北极生态系统的变化。然而，由于我们对控制这种温水潜没和演化的物理过程缺乏了解，我们理解或预测这种传入水团的作用的能力受到了阻碍。至关重要的是，这里看到的过程发生在小的水平尺度上，区域预报模型或气候模拟无法解决；必须开发新的参数化方案，以准确表示物理过程。在这里，我们提出了新的高分辨率观测结果，展示了在波弗特环流南部温水潜没和初始演化的详细过程。
