A Multiport CO₂ Extraction System for Accurate and Precise Measurements from Small Ice Core Samples

Ice cores serve as valuable archives for past atmospheric conditions. They can provide direct records of past atmospheric CO₂ concentrations, but measurements from very old or stratigraphically disturbed ice are often limited by sample size and analytical precision. This study presents a custom-built multiport CO₂ extraction and crushing system designed to enable accurate and precise CO₂ concentration measurements from small ice samples (~10 g) with faster throughput than previous systems at OSU. The system allows sequential extraction of multiple samples under identical analytical conditions, improving throughput while minimizing contamination and analytical drift with ultimate throughput of 8-12 samples per day. 

We evaluate the performance of the multiport system through repeated analyses of ice standards and replicate small-sample measurements, assessing reproducibility, extraction efficiency, and measurement precision. CO₂ concentrations measured using this system demonstrate consistent reproducibility across ports, with precision comparable to previous methods at OSU. This method enables faster higher spatial resolution sampling and provides a foundation for improving CO₂ measurements in ancient ice where sample availability and potential respiratory inputs are key challenges.