Fractional abundances and concentrations of branched glycerol dialkyl glycerol tetraethers (brGDGT) of core SO201-2-12KL

Little is known about the climate evolution on the Kamchatka Peninsula during the last glacial?interglacial transition as existing climate records do not reach beyond 12 ka BP. In this study, a summer temperature record for the past 20 kyr is presented. Branched glycerol dialkyl glycerol tetraethers, terrigenous biomarkers suitable for continental air temperature reconstructions, were analyzed in a sediment core from the western continental margin off Kamchatka in the marginal northwest Pacific (NW Pacific). The record suggests that summer temperatures on Kamchatka during the Last Glacial Maximum (LGM) equaled modern temperatures. We suggest that strong southerly winds associated with a pronounced North Pacific High pressure system over the subarctic NW Pacific accounted for the warm conditions. A comparison with an Earth system model reveals discrepancies between model and proxy-based reconstructions for the LGM temperature and atmospheric circulation in the NW Pacific realm. […]

关于堪察加半岛在末次冰期至间冰期过渡期间的气候演变，知之甚少，因为现有的气候记录未能追溯至12千年前。在本研究中，我们呈现了过去20万年的夏季温度记录。通过对位于堪察加半岛西部大陆边缘、西北太平洋（西北太平洋）边缘的沉积岩芯中分支甘油二烷基甘油四醚（一种适用于大陆气温重建的陆源生物标志物）的分析，我们揭示了这一记录。该记录表明，在末次冰盛期，堪察加半岛的夏季温度与现代温度相当。我们认为，与亚北极西北太平洋上显著的北太平洋高压系统相关的强南风是导致温暖气候的原因。与地球系统模型的比较揭示了模型与基于代理的重建在西北太平洋领域中末次冰盛期的温度和大气环流之间存在差异。