Climatic implications of background acidity and other chemistry derived from electrical studies of the Greenland Ice Core Project ice core
Climatic implications of background acidity and other chemistry derived from electrical studies of the Greenland Ice Core Project ice core
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格陵兰冰芯项目冰芯电学研究得出的背景酸度和其他化学成分对气候的影响
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
C. Hammer
中科院分区：
文献类型：
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作者：
E. Wolff;J. Moore;H. Clausen;C. Hammer
采用两种不同的电方法，在格陵兰冰芯项目（GRIP）冰芯上获得了高分辨率的连续剖面。在对温度和密度进行校正后，电导率法（ECM）技术只对酸度有反应，而介电谱法（DEP）对酸、铵和氯化物有反应。在冰期冰剖面上进行详细的化学分析，使我们能够确定DEP中氯化物的校准因子。在全新世、Allerod/Bolling和更大的间冰期，酸度主导着DEP的变化；在新干期，铵元素占主导地位，而在冷期，包括较小的间冰期，氯化物是主要贡献者。从绘制在线性时间尺度上的电信号中，我们可以推断出冰的背景（非火山）酸度，从全新世的酸性到寒冷时期的碱性。在间冰期，冰接近中性，较大的间冰期以酸性为主，较小的间冰期以碱性为主，间冰期内变化迅速。目前尚不清楚是否在大气中发生了单个酸性颗粒的中和，或者酸性和碱性颗粒是否共存，直到沉积在积雪中。GRIP观测到的酸度变化至少适用于整个格陵兰岛，可能也适用于北美的大部分地区。一些化学物质在冰面上的吸收可能会产生生态效应和重大变化。如果酸性硫酸盐颗粒被中和并从大气中移除（这一点仍不确定），那么大气化学和辐射效应需要进一步研究。
High-resolution continuous profiles were obtained on the Greenland Ice Core Project (GRIP) ice core using two different electrical methods. After correction for temperature and density, the electrical conductivity method (ECM) technique responds only to acidity, while dielectric profiling (DEP) responds to acid, ammonium, and chloride. Detailed chemistry on a section of glacial-age ice allows us to confirm the calibration factor for chloride in DEP. Acidity dominates the DEP variability in the Holocene, Allerod/Bolling, and larger interstadials; ammonium dominates in the Younger Dry as, while chloride is the major contributor in cold periods including smaller interstadials. From the electrical signals plotted on a linear timescale we can deduce the background (nonvolcanic) acidity of the ice, varying from always acidic in the Holocene to always alkaline in the cold periods. In the interstadials, the ice is close to neutral, with most of it acidic in larger interstadials, most of it alkaline in smaller ones, and rapid alternations within interstadials. It is not clear whether neutralization of individual acidic particles occurred in the atmosphere or whether acid and alkaline particles coexisted until deposition in the snowpack. The changes in acidity observed at GRIP apply at least to all of Greenland and probably to much of North America. There would have been ecological effects and important changes in the uptake of some chemicals onto ice. If acidic sulfate particles were neutralized and removed from the atmosphere, which remains uncertain, then there are atmospheric chemistry and radiative effects that require further investigation.