东南极冰盖泰山站雪层垂直温度分布特征研究

ANALYSIS OF THE VERTICAL TEMPERATURE DISTRIBUTION OF SHALLOW SNOW LAYERS NEAR TAISHAN STATION, EAST ANTARCTICA

准确可靠的冰盖浅层冰雪温度是数值模式中评估极地冰盖物质平衡和能量平衡的重要因子。基于中国第32次南极科学考察在泰山站附近布放的综合监测站浅层10 m温度链观测数据,首次获得了泰山站雪层的高精度积雪温度垂直廓线,并探讨了表层积雪温度的日变化、月变化和季节变化特征。结果表明,冰盖雪层温度存在随深度传导的特点:雪层温度波动振幅随深度衰减,波动相位随深度滞后,波动曲线的波峰和波谷由表层向下传导至10 m深度均需100多天。泰山站冰盖表层积雪温度存在显著季节差异,冬季与夏季、春季与秋季的温度垂直轮廓线均相反但不完全对称,夏季表层的温度变化幅度要大于冬季的温度变化幅度,而秋季表层的温度变化幅度也高于春季的温度变化幅度,这与短波辐射的加热作用和季节波动的位相滞后存在密切的联系。

Accurate and reliable measurements of near surface ice temperatures provide important inputs to numerical models that assess the mass and energy balances of polar ice sheets. Based on observation data collected from the 10 m temperature chain at Taishan Station during the 32 nd Chinese Antarctic Research Expedition during 2015–2016, the high-resolution vertical profiles of snow temperature at Taishan Station was measured for the first time. The daily, monthly and seasonal characteristics of near-surface snow temperatures are discussed. Results show that the characteristics of heat transfer in the firn. Variations in temperature decrease with depth into the firn, while the phase of temperature variations exhibits gradually increasing lag with depth. The peak and trough of temperature fluctuations are delayed by more than 100 days from the near ground to a depth of 10 m. Additionally, there are notable seasonal distinctions in the vertical firn temperature regime. The temperature distribution profiles in winter and summer or spring and autumn are opposite but not completely symmetrical. The amplitude of near-surface temperature fluctuations in the summer is larger than that in winter, and the amplitude of near-surface temperature fluctuations in autumn is higher than that in spring, which is closely related to the heating effect of shortwave radiation and the phase lag of seasonal temperature fluctuations.