干旱区生态环境知识资源中心

Major ions, stable oxygen isotopes (delta O-18), and accumulation rates are analyzed using high temporal resolution data from shallow ice cores and snow pits from East and West Antarctica. Seasonal cycles of major ions and delta O-18 are well preserved at sites with an accumulation rate threshold of >100 kg m(-2) a(-1) and calm wind conditions. The seasonal cycle is unclear at sites with high wind speeds, even if the accumulation rate is greater than the threshold. To eliminate the influences of different source regions on major ion and delta O-18 signals in ice cores, we calculate correlation coefficients between annually averaged major ion concentrations and delta O-18, and then compare these with accumulation rates and other geographical variables such as latitude, elevation, and distance from the coast. We find that accumulation rates are highly correlated with elevation and the 10-m snow temperature, and that major ions and delta O-18 are negatively correlated at low accumulation sites in inland Antarctica. Negative correlations could reflect inconsistent accumulation due to a large inter-annual variability in the accumulation rate. The results show that the relationships between major ions and delta O-18 may not reflect climatic signatures, and could be a result of the unique characteristics of this arid environment. (C) 2015 Elsevier B.V. and NIPR. All rights reserved.