利用2005年5月1日至7月22日在东绒布冰川海拔6 523 m的若普拉垭口架设的自动气象站获得的各辐射参数资料,分析了该地区总辐射、地面反射辐射、地面长波辐射、天空长波辐射的日平均变化和平均日变化,并计算了反射率和辐射平衡.结果表明:1)短波辐射的平均日变化都随着太阳高度角的增大而加强,并且总辐射和地面反射辐射的日平均变化有很好的相关性,观测期间二者的月平均值都在5月份最大.由于垭口新降雪较多,雪面的反射率也很高;2)天空长波辐射的平均日变化比地面长波辐射变化滞后2 h,且其日平均变化幅度比地面长波辐射的变化幅度大;3)净辐射的平均日变化随着太阳高度角的变化而变化,下午14:00时净辐射最大,其日平均变化在观测期间整体上有增大趋势.
Diurnal mean variation and variations of mean daily variations of global radiation, surface short-wave radiation, surface long-wave radiation, atmospheric counter-radiation are analyzed by using the radiation parameters obtained from the automatic weather station over the Ruopula pass of the East Rongbuk Glacier (at an elevation of 6523 m) from May 1 to July 22, 2005, the surface albedo and the radiation balance. The short-wave radiation has a big change with the solar elevation angle increasing, and the daily global radiation has a good correlation with the surface short-wave radiation. The surface albedo is higher due to new snow always falling. Diurnal variation of atmospheric counter radiation lags for 2 hours behind the surface long wave radiation change, with a daily variation larger than that of the surface long-wave radiation. Diurnal mean net radiation changes with solar elevation angle increasing. There is an increasing tendency of the daily radiation balance during the observing duration.