Freezing rate determination by the isotopic composition of the ice

The distribution of an isotopic species, HDO (deuterium) or H 2 18 O (oxygen), in ice formed by the migration of a well‐defined freezing front in water is dependent on the freezing rate. Development of a box diffusion model combined with the boundary layer concept leads to a possibility of prediction of the freezing rate in nature by the determination of the isotopic composition of the ice in δD or δ 18 O. The isotopic distribution in ice formed during experiments conducted with variable freezing rates gives results in accordance with the model. Investigation on lake ice formed under well‐known climatic conditions provides a further test of the model.