Liu Yonggang, Zhang Ming, Liu Zhengyu, Xia Yan, Huang Yi, Peng Yiran, Zhu Jiang
Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, 100871, China.
Atmospheric Science Program, Department of Geography, Ohio State University, Columbus, Ohio, 43210, USA.
Sci Rep. 2018 Mar 13;8(1):4434. doi: 10.1038/s41598-018-22841-5.
Climate models generally fail to produce a warmer (by as much as 0.5 °C) early to mid-Holocene than the pre-industrial in the global annual temperature, which has been termed the Holocene temperature conundrum. Here we use a fully coupled atmosphere-ocean general circulation model to test whether the conundrum can be partially resolved by considering the fact that atmospheric dust loading was much reduced during the early to mid-Holocene. Our experiments show that the global annual mean surface temperature increases by 0.30 °C and 0.23 °C for the mid-Holocene (6 ka) and early Holocene (9 ka), respectively, if the dust is completely removed. The temperature increase scales almost linearly with the fraction of dust being removed, with the 50% dust reduction experiment for the 6 ka being the only one deviating from the linear trend. The indirect effect of dust, which is highly uncertain and is not included in the model, may further enhance the warming. Therefore, the neglect of dust reduction in the Holocene in climate models could contribute significantly to the model-data discrepancy, especially in the Northern Hemisphere.
气候模型通常无法得出全新世早期至中期的全球年平均温度比工业化前时期更暖（高达0.5°C）的结果，这一情况被称为全新世温度之谜。在此，我们使用一个完全耦合的大气-海洋环流模型来检验，通过考虑全新世早期至中期大气尘埃负荷大幅减少这一事实，该谜团是否能得到部分解决。我们的实验表明，如果完全去除尘埃，全新世中期（6000年前）和全新世早期（9000年前）的全球年平均地表温度分别升高0.30°C和0.23°C。温度升高几乎与去除的尘埃比例呈线性关系，6000年前50%尘埃减少实验是唯一偏离线性趋势的实验。尘埃的间接效应高度不确定且未包含在模型中，可能会进一步加剧变暖。因此，气候模型中忽略全新世尘埃减少的情况可能会显著导致模型与数据之间的差异，尤其是在北半球。
