(Table 1) Snow and sea ice thickness, solar heat input and solar heat used for melting at seven ice mass-balance buoys in the Arctic in 2008

There has been a marked decline in the summer extent of Arctic sea ice over the past few decades. Data from autonomous ice mass-balance buoys can enhance our understanding of this decline. These buoys monitor changes in snow deposition and ablation, ice growth, and ice surface and bottom melt. Results from the summer of 2008 showed considerable large-scale spatial variability in the amount of surface and bottom melt. Small amounts of melting were observed north of Greenland, while melting in the southern Beaufort Sea was quite large. Comparison of net solar heat input to the ice and heat required for surface ablation showed only modest correlation. However, there was a strong correlation between solar heat input to the ocean and bottom melting. As the ice concentration in the Beaufort Sea region decreased, there was an increase in solar heat to the ocean and an increase in bottom melting.

近数十年来，北极海冰夏季范围呈现显著缩减趋势。自主式冰质量平衡浮标（autonomous ice mass-balance buoys）的观测数据可进一步加深我们对这一缩减过程的认知。此类浮标能够监测积雪沉积与消融、海冰生长，以及海冰表面与底部融化的动态变化。2008年夏季的观测结果显示，海冰表面与底部融化量存在显著的大范围空间变异性：格陵兰岛北部仅观测到少量融化，而波弗特海南部的融化量则相当可观。对海冰接收的净太阳热输入与表面消融所需热量进行对比后发现，二者仅存在弱相关性；然而，海洋吸收的太阳热输入与海冰底部融化却呈现极强的相关性。随着波弗特海区域的海冰密集度降低，海洋吸收的太阳热通量随之增加，海冰底部融化也相应加剧。