The Last Interglacial (~129,000–116,000 years ago) is the most recent geologic period with a warmer-than-present climate. Proxy-based temperature reconstructions from this interval can help contextualize natural climate variability in our currently warming world, especially if they can define changes on decadal timescales. Here, we established a ~4.800-year-long record of sea surface temperature (SST) variability from the eastern Mediterranean Sea at 1–4-year resolution by applying mass spectrometry imaging of long-chain alkenones to a finely laminated organic-matter-rich sapropel deposited during the Last Interglacial. We observe the highest amplitude of decadal variability in the early stage of sapropel deposition, plausibly due to reduced vertical mixing of the highly stratified water column. With the subsequent reorganization of oceanographic conditions in the later stage of sapropel deposition, when SST forcing resembled the modern situation, we observe that the maximum amplitude of reconstructed decadal variability did not exceed the range of the recent period of warming climate. The more gradual, centennial SST trends reveal that the maximal centennial scale SST increase in our Last Interglacial record is below the projected temperature warming in the twenty-first century.

末次间冰期（约 129,000 至 116,000 年前）是最近的地质时期，气候比现在温暖。从这个区间进行基于代理的温度重建可以帮助将我们目前正在变暖的世界中的自然气候变化背景化，特别是如果它们可以定义十年时间尺度上的变化。在这里，我们通过将长链烯酮的质谱成像应用于精细层压的有机物质，以 1-4 年的分辨率建立了东地中海海表温度 (SST) 变化的约 4.800 年记录。末次间冰期沉积的丰富腐泥。我们观察到腐泥沉积早期的年代际变化幅度最大，这似乎是由于高度分层的水柱的垂直混合减少。随着随后腐泥沉积后期海洋条件的重组，当SST强迫与现代情况相似时，我们观察到重建的年代际变率的最大幅度没有超过近期气候变暖的范围。更渐进的百年海温趋势表明，我们最后一次间冰期记录中的最大百年海温增加低于 21 世纪预计的温度变暖。