High carbon dioxide levels are associated with warm interglacial periods, and low levels with cold glacial periods.
高二氧化碳含量与温暖的间冰期有关，低二氧化碳含量与寒冷的冰期有关。
2
When snowfalls on high mountains or in polar regions, it may become part of the glacial system.
当雪落在高山或极地地区时，它可能成为冰川系统的一部分。
3
Recent studies do in fact show that high carbon dioxide levels are associated with warm interglacial periods, and low levels with cold glacial periods.