Table 3.1 Content and composition of air in an ice profile from Camp III i Greenland

The air trapped in freshly formed ice gives information concerning the ice formation processes as weH as concerning severa,l environmental parameters at the time of ice formation. Air arnount, air composition, and the size and form of bubbles may change with time. Possible processes responsible for such changes are discussed. In very cold ice air content and air composition remain almost unchanged. Samples of ancient atmospheric air are therefore very weH preserved in cold ice. In temperate ice changes of the air amount and air composition depend on the intergranular water fiow through the glacier. This waterfiow can be estimated by measuring air amount and air composition in ice sampIes.新形成的冰中捕获的空气，既可反映冰的形成过程，也可揭示冰形成时期的多项环境参数。气泡的空气含量、组分以及尺寸与形态均可能随时间发生变化，本文探讨了引发此类变化的潜在机制。 在极寒冰层中，空气含量与组分几乎保持不变，因此古老大气样本可在寒冰中得到极佳保存。而在温性冰层中，空气含量与组分的变化取决于流经冰川的粒间水流；通过测定冰样中的空气含量与组分，即可估算该粒间水流的规模。