氷床コア中の溶存イオン成分の連続融解分析装置の開発 ‐南極みずほコアの分析テスト‐

第6回極域科学シンポジウム[OM] 極域気水圏11月16日（月）　国立極地研究所１階交流アトリウ

The new frontier of microstructural impurity research in polar ice

Deciphering the localisation of solid and dissolved impurities on the micron-scale in glacial ice remains a challenge, but is critical to understand the integrity of ice core records and internal deformation. Here we report on the state-of-the-art in microstructural impurity research by high- lighting recent progress in bringing together cryo-Raman spectroscopy and laser ablation induct- ively coupled plasma mass spectrometry (LA-ICP-MS). We show the potential of both methods and discuss possibilities to improve inter-method approaches aiming for a more holistic under- standing of the evolution of impurity localisation throughout the ice column, including post-depositional processes. In this framework, we elaborate on future research priorities such as LA-ICP-MS imaging on firn samples and integrating a large cryo-cell with imaging capabilities

Stratigraphic noise and its potential drivers across the plateau of Dronning Maud Land, East Antarctica

Stable water isotopologues of snow, firn and ice cores provide valuable information on past climate variations. Yet single profiles are generally not suitable for robust climate reconstructions. Stratigraphic noise, introduced by the irregular deposition, wind-driven erosion and redistribution of snow, impacts the utility of high-resolution isotope records, especially in low-Accumulation areas. However, it is currently unknown how stratigraphic noise differs across the East Antarctic Plateau and how it is affected by local environmental conditions. Here, we assess the amount and structure of stratigraphic noise at seven sites along a 120 km transect on the plateau of Dronning Maud Land, East Antarctica. Replicated oxygen isotope records of 1 m length were used to estimate signal-To-noise ratios as a measure of stratigraphic noise at sites characterised by different accumulation rates (43-64 mm w.e. a-1), snow surface roughnesses and slope inclinations. While we found a high level of stratigraphic noise at all sites, there was also considerable variation between sites. At sastrugi-dominated sites, greater stratigraphic noise coincided with stronger surface roughnesses, steeper slopes and lower accumulation rates, probably related to increased wind speeds. These results provide a first step to modelling stratigraphic noise and might guide site selection and sampling strategies for future expeditions to improve high-resolution climate reconstructions from low-Accumulation regions

Holocene CH4 concentrations in the NEEM ice core (preliminary results)

第4回極域科学シンポジウム横断セッション：[IA] 「急変する北極気候システム及びその全球的な影響の総合的解明」―GRENE北極気候変動研究事業研究成果報告2013―11月12日（火） 国立極地研究所 ２階大会議

Development of continuous flow analysis system of chemical consituents in ice core

Chemical constituents in ice core samples are proxy for past environmental condition of the earth. Conventional method for major ion analysis requies liquid samples preparation from ice core samples. Cutting and decontamination process of ice sample is labor work in cold laboratory and clean room. And these process make difficult for high spatial resolution analysis. Continuous Flow Analysis (CFA) system is developed by Sigg and others (1994) and it is applied for GRIP ice core analyis. This system foward the chamical analysis and improved resolution in mm order. Röthlsberger and others(2000) improved CFA for low concentration and firn sample. Present CFA system connects many analytical equipments in order to determinate many chamical species in liquid and composition of air. But uncertain of depth for each analysis is remained.We planed to develop CFA-IC system which is conbination of continuous melting of ice sample and chamical analysis using ion chromatography. Simillar system is already developed by Huber and others (2001) and therefore we made simillar flow line with this. Analysis speed ion chromatograpy is quite slow and unsuitable for CFA but it can analyse more than 10 ion species from same sample of 1cc and this is advantage for comparison with physical property analysis of ice core study. Present situation of our development is complete to make flow line and program of control/monitor for each devices. We are now making sequencial program for whole control of CFA system.第4回極域科学シンポジウム個別セッション：[OM] 気水圏11月15日（金） 国立極地研究所 ３階ラウン

High Resolution Continuous Flow Analysis System developed at the Ice Core Research Center National Institute of Polar Research

第6回極域科学シンポジウム[OM] 極域気水圏11月16日（月）　統計数理研究所 セミナー室2（D304

Continuous CH4 measurements with the NIPR CFA system

第6回極域科学シンポジウム分野横断セッション：[IA] 急変する北極気候システム及びその全球的な影響の総合的解明―GRENE北極気候変動研究事業研究成果報告2015―11月19日（木）　国立極地研究所１階交流アトリウ