中国西天山季节性积雪热力特征分析  

Characteristic Analysis on Temperature Change in Snow Layer in Western Tianshan Mountain in China

作　　者：高培[1] 魏文寿[2] 刘明哲[3] 

机构地区：[1]新疆信息工程学校,新疆乌鲁木齐830013 [2]新疆维吾尔自治区气象局,新疆乌鲁木齐830002 [3]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011

出　　处：《高原气象》2012年第4期1074-1080,共7页Plateau Meteorology

基　　金：中国科学院"西部之光"项目(RCPY200902);科技部公益行业科研专项(GYHY200806011);国家自然科学基金项目(41171066)共同资助

摘　　要：利用中国天山积雪雪崩站干、湿雪雪层内每隔5min一次的10层雪温数据,探讨了一次降雪过程后干、湿雪的雪层温度特征,对比分析了干、湿雪的雪面能量平衡方程中各分量的差异。结果表明:(1)整个冬半年积雪各层温度基本<0℃,雪温日变化振幅由雪面向下逐渐减小,积雪深层温度的波峰(谷)值稍滞后于积雪浅层温度极值1～2天。(2)湿雪冷中心的出现时间早于干雪,暖中心的出现时间晚于干雪,太阳辐射对湿雪的穿透深度大于干雪。(3)雪层温度振幅变化与能量吸收随雪深都呈指数衰减分布。积雪密度越大,吸收系数越小,穿透深度越大。(4)干雪雪面的感热通量和潜热通量几乎都为负值,积雪积累。湿雪雪面的潜热通量与感热通量方向相反,互相抵消,所以净辐射是导致湿雪消融的主要因素。The temperature features of dry snow and moist snow after snowfall were discussed based on the temperature data in 10 snow layers every 5 min at a time at Tianshan Avalanche station. The results show that. （1） The temperature in every snow layer is below zero in winter, the amplitudes of snow tem- perature at the top of the snow cover layer is larger than that of the bottom. The occurrence of the tem- perature extremum at the top snow layer is earlier one or two days than that of the bottom. （2） The oc- currence of cold center of moist snow is earlier than that of dry snow, however, the occurrence of the warm center of moist snow is later than that of the dry snow. And the solar radiation can penetrate the moist snow deeper than that of dry snow. （3） The distribution of solar radiation in the snow layer and the amplitudes of snow temperature are both depended on Lambertrs Law. Depth of penetration increases with the increasing of the snow density. （4） The sensible heat and latent heat fluxes in dry snow are both be- neath zero, so snow is accumulated the sensible heat flux and latent heat flux exchanges in moist snow are counteract, therefore, the net radiation is main factors leading to melt the snow.

关 键 词：中国西天山 雪层温度 净辐射 感热通量 潜热通量 

分 类 号：P426.635[天文地球—大气科学及气象学]