北极夏季冰面上近地层特征及热量收支问题

Characteristics of the atmospheric surface layer and heat budget over the Arctic ice in summer

应用1999年8月19～24日我国第1次北极考察资料对北极夏季近地层气象要素梯度特征和冰面热量收支问题进行了讨论.北极夏季近地层相对于冰面的相对湿度很大,经常接近于饱和状态,冰温具有明显的日变化,夜间冰面附近冰温梯度较大,白天很小.在冰温垂直分布中20cm冰层温度有时可出现极大值.冰面热量收支计算表明,夜间冰面辐射冷却损失热量主要由冰层向冰面热量输送来补偿.白天冰层的热量主要来源于穿透短波辐射,冰面和以下冰层间的热量交换很低.白天冰面冰雪融化热量是不可忽视的.

analyzed Observational data of August 19 - 24, 1999 during and the vertical distribution of meteorological variables the first Chinese arctic research exploration were in the surface layer and the heat budget problem over ice in the Arctic region in summer were discussed. The results show that the humidity of surface layer is very high significant very small relative to the ice surface, and is often close to its saturated value. The ice temperature has a diurnal variation. The ice temperature gradient during daytime. near the surface is relatively large at night, and is For the top 40cm of ice, the ice temperature sometimes reaches a maximum value at 20cm depth. The heat budget analysis shows that the heat loss during effect is compensated by heat transferred from the inner ice layer to the night caused by the radiation cooling ice surface. In daytime, the inner ice heat comes mainly from penetrating shortwave radiation, and heat exchange between the ice surface and inner ice is very weak. The ice/snow thaw heat in daytime can not be neglected.