当前位置: X-MOL 学术Earth Planet. Sci. Lett. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Solar and climate signals revealed by seasonal 10Be data from the NEEM ice core project for the neutron monitor period
Earth and Planetary Science Letters ( IF 5.3 ) Pub Date : 2020-07-01 , DOI: 10.1016/j.epsl.2020.116273
Minjie Zheng , Florian Adolphi , Jesper Sjolte , Ala Aldahan , Göran Possnert , Mousong Wu , Peng Chen , Raimund Muscheler

Abstract 10Be in ice cores has been instrumental for reconstructing past changes in solar activity prior to direct observations. For a robust use of these records, it is pivotal to understand the 10Be transport and deposition. However, there are only few high-resolution seasonal 10Be data longer than one full solar cycle (11 years) that could enable a quantification of the influences of atmospheric circulation and deposition processes on the 10Be signal in ice. Here we present a seasonally resolved 10Be data set covering the neutron monitor period (1951–2002) from a firn core connected to the NEEM (North Greenland Eemian Ice Drilling) project. The results suggest that both summer and winter 10Be reflect the production signal induced by solar modulation of galactic cosmic rays. However, superimposed on this solar signal we find additional meteorologically driven influences on 10Be transport and deposition. We found that the tropopause pressure over 30°N represents an important factor influencing NEEM 10Be concentrations on seasonal and annual scales. 10Be deposited in summer also correlates significantly with the tropopause pressure over Greenland suggesting a direct contribution of stratospheric intrusions during summer to the 10Be deposition in Greenland. To correct for these transport/deposition influences, we apply a first-order correction to the 10Be data using a multi-linear regression model. The “climate-corrected” 10Be data shows a comparable skill for reconstructing production rate changes as the 10Be composite record from five different ice cores in Greenland. The results suggest that the correction approach can be a complementary method to the stacking to better isolate the production rate signal from the 10Be data when only limited data are available.

中文翻译:

中子监测期 NEEM 冰芯项目的季节性 10Be 数据揭示的太阳和气候信号

摘要 冰芯中的 10Be 有助于在直接观测之前重建过去的太阳活动变化。为了充分利用这些记录,了解 10Be 传输和沉积至关重要。然而,只有少数超过一个完整太阳周期(11 年)的高分辨率季节性 10Be 数据可以量化大气环流和沉积过程对冰中 10Be 信号的影响。在这里,我们提供了一个季节性解析的 10Be 数据集,涵盖了与 NEEM(北格陵兰伊米安冰钻)项目相连的冷杉岩心的中子监测期(1951-2002 年)。结果表明,夏季和冬季的 10Be 都反映了由银河宇宙射线的太阳调制引起的产生信号。然而,叠加在这个太阳信号上,我们发现了额外的气象驱动对 10Be 传输和沉积的影响。我们发现超过 30°N 的对流层顶压力是影响季节和年度尺度上 NEEM 10Be 浓度的重要因素。夏季沉积的 10Be 还与格陵兰上空的对流层顶压力显着相关,表明夏季平流层侵入对格陵兰 10Be 沉积的直接贡献。为了校正这些传输/沉积影响,我们使用多元线性回归模型对 10Be 数据应用一阶校正。“气候校正”的 10Be 数据显示了与来自格陵兰五个不同冰芯的 10Be 复合记录重建生产率变化的类似技能。
更新日期:2020-07-01
down
wechat
bug