资源环境科技发展态势分析平台

Equatorward sea ice drift can have competing impacts on the sea ice cover. On one hand, as ice reaches warmer waters it will be subject to faster melt. On the other hand, the ice near the pole will thin, causing faster ice growth when air temperatures are below freezing. This prompts the fundamental question whether equatorward ice motion increases or decreases ice area and volume? We investigate this using an idealized global climate model with a representation of sea ice thermodynamic processes and specified sea ice drift. We find that equatorward ice drift leads to consistent loss of ice volume. The impact of ice motion on ice area depends on seasonal factors and the background climate: When there is enough ice, equatorward ice motion slightly expands ice area. For thinner ice, however, motion during the melt season can create polynyas and cause substantial ice loss that persists throughout the year.