Study on environmental signals in polar ice core and reconstruction of environmental change

对上一财政年度后2001年衍生的Dome Fuji冰芯进行了基本分析。要分析的环境信号及其环境信息如下：(1)可见观测--沉积条件；(2)密度剖面--雪密化过程；--积雪速率的基本信息；(3)冰--Gt的电导率；冰的物理性质、冰的酸度(季节变化)、火山喷发(4)稳定同位素(d18O，dd)-gt；温度变化、水汽输送、季节变化、降水(5)化学--gt；气溶胶剖面、陆地/海洋/大气状况。作为具体的研究，更详细的环境变化，利用宇宙射线产生核素的量或硝酸盐浓度来研究太阳活动的历史。关于冰芯年龄作为基本的核心信息，一般通过探测火山喷发的痕迹电导率和非海盐浓度的变化来确定精度。关于这个圆顶富士冰芯，1993年在44m外的同一点的浅冰芯进行了采样，并通过两种数据的比较得出了有趣的研究结果。富士穹顶的沉积环境目前被认为是统一的。但在几个10m的范围内出现了不同的沉积。特别是氧同位素组成。就化学的特点而言，有一些典型的元素表现出相同的变化或不同的变化。通过综合考察，将富士圆顶3029m冰芯获得的环境信号恢复为过去的环境信息，显然从现在开始应该立即进行查询。

Basic analysis was carried out for the Dome Fuji ice core derived in 2001 following the last fiscal year. The environmental signal to analyze and its environment information are as follows, (1)visible observation -> depositional condition, (2)density profile -> snow densification process, basic information for accumulation rate (3)electrical conductivity of ice -> physical property of ice, acidity of ice (seasonal variation), volcanic eruption (4)stable isotope (d18O, dD) -> temperature variation, water vapor transport, seasonal variation, precipitation (5)chemistry -> aerosol profile, condition of land/ocean/atmosphere.Special analysis was also carried out with basic analysis. As specific research, more detailed environmental change, the history of solar activity research using the amount of cosmic ray generation nuclide or the concentration of nitrate.About the ice core age used as fundamental core information, the accuracy for less than five years determined in general by detecting the trace of volcanic eruptions from change of electrical conductivity and non-sea salt sulfate concentration.About this Dome Fuji ice core, the shallow ice core same at the point 44m away in 1993 was sampled, and the interesting research result was obtained from comparison of both data. The deposition environment of Dome Fuji currently considered to be uniform. But the different of deposition was appeared within several 10m. It showed especially the oxygen isotopic composition. For characteristics of chemistry, there are typical elements in which the same change or the different change are shown. It became clear restoring the environmental signal obtained from the 3029 m ice core at Dome Fuji to the past environment information by examining these synthetically that it should inquire immediately from now on.