根据2006年夏季“七一”冰川自动气象站和光谱仪的反照率资料,分析了夏季“七一”冰川反照率的时、空变化特征.结果表明:夏季“七一”冰川反照率的日际变化受气温影响明显,冰川上、下部位反照率差值动态变化并具有一定的日变化特征.冰川表层积雪随着变质作用的增强,其光谱反射率不断下降,其中紫外和红橙光波段反照率降幅较大(尤其是紫外波段),在紫蓝波段降幅相对较小.晴天时,雪面上紫外及可见光波段反照率日变化幅度要比在冰面上的变幅大,日变化曲线在雪面时也不对称.冰面上各波段反照率日变化较平缓,曲线则都比较对称.无论在雪面还是冰面,近红外波段反照率日变化曲线均比较对称.冰川上全波段反照率的日变化曲线形式趋同于可见光波段反照率的日变化曲线.同时,文中还初步分析了反照率和积雪密度,积雪污化浓度之间的关系,以及反照率变化对径流的影响.
Based on the data of albedo from one Automatic Weather Station (AWS) and one PC-2GL solar spectrum analysis system installed on the Qiyi Glacier in the summer of 2006, the temporal and spatial characteristics of albedo on the glacier have been analyzed. The results indicate that, in summer, the interdiurnal change of albedo on the glacier significantly affected by the air temperature, the difference of albedo between the upper and lower sites on the glacier varies with time and has the characteristic of diurnal cycle. The spectral reflectance declines with the deterioration of snow. In ultraviolet (280-400 nm) and 6004700 nm wavelength (especially in ultraviolet), it declines drastically, while it declines less in 400 - 500 nm wavelength. On snow cover during fine days, the reflectance of ultraviolet and visible wave changes quicker than that on ice surface, and the diurnal variation of it is not symmetry before and after local noontime. Comparing the diurnal variation curves of reflectance on ice surface with that on snow surface, one can see that the curves on ice surface in every wave band are relatively flat and symmetry. The surface reflectance in near infrared band is flat and symmetry on either of snow and ice surface on the glacier. The diurnal variation of overall albedo is similar to that of visible light. The relations between the snow albedo and snow density and impurity, and the impact of the glacier albedo on the Qiyi Glacier runoff were also studied in this paper.