英国伦敦皇家霍洛威大学Martin-Puertas的团队发现，冰融化限制了可预测的北大西洋十年际的气候波动。相关论文于2023年3月23日发表于国际顶尖学术期刊《自然—地球科学》杂志上。
该研究团队仪基于英国一个湖泊的年代分层气候记录和大西洋经向翻转环流的长期瞬态模拟输出，进行频率分析，研究了10500年到2000年前，北大西洋地区全新世气候变率的重现成分。该研究团队在过去的6700年里在8500年间有一致的十年际变化，可能反映了太阳和海洋营力的优势。这些日期之间，气候变化在十年际时间尺度上减弱了。研究结果表明，哈德逊湾的开放到劳伦提德冰盖的最终崩溃，融水排入北大西洋和随后的水文变化，扰乱了一千多年的十年际周期信号。鉴于目前格陵兰冰盖因全球变暖而加速融化，这项研究为预测气候系统未来模式的潜在挑战提供了长期的证据。
据悉，使用仪器记录之前，气候系统在十年时间尺度上的振荡行为很难被量化。然而，这种可变性的知识对于将当前的变化置于当前情景中和支持可靠的未来预测是非常重要的。
附：英文原文
Title: Dampened predictable decadal North Atlantic climate fluctuations due to ice melting
Author: Martin-Puertas, Celia, Hernandez, Armand, Pardo-Igzquiza, Eulogio, Boyall, Laura, Brierley, Chris, Jiang, Zhiyi, Tjallingii, Rik, Blockley, Simon P. E., Rodrguez-Tovar, Francisco Javier
Issue&Volume: 2023-03-23
Abstract: The oscillatory behaviour of the climate system on decadal timescales before the instrumental record is hard to quantify. However, knowledge of this variability is important for putting current changes in context and for supporting reliable future predictions. Here we investigate the recurrent component of Holocene climate variability in the North Atlantic sector from 10,500 to 2,000 years ago by conducting a frequency analysis of both an annually laminated climate record from a lake in England and outputs from a long transient simulation of the Atlantic meridional overturning circulation. We find consistent decadal variability over the past 6,700 years and before 8,500 years before present, probably reflecting predominance of solar and ocean forcings. Between these dates, climate variability was dampened on decadal timescales. Our results suggest that meltwater discharge into the North Atlantic and the subsequent hydrographic changes, from the opening of the Hudson Bay until the final collapse of the Laurentide Ice Sheet, disrupted the decadal cyclic signals for more than a millennium. Given the current acceleration of the Greenland Ice Sheet melting in response to global warming, this study provides long-term evidence of potential challenges predicting future patterns of the climate system.
DOI: 10.1038/s41561-023-01145-y
Source: https://www.nature.com/articles/s41561-023-01145-y