地理学报 ›› 1999, Vol. 66 ›› Issue (4): 309-317.doi: 10.11821/xb199904003

• 论文 • 上一篇    下一篇

用NCEP/NCAR再分析辐射资料估算月平均地表反照率

张琼, 钱永甫   

  1. 南京大学大气科学系,南京210093
  • 收稿日期:1998-03-18 修回日期:1998-06-27 出版日期:1999-07-15 发布日期:1999-07-15
  • 基金资助:
    国家自然科学基金重点资助项目(49735170)

Monthly Mean Surface Albedo Estimated From NCEP/NCAR Reanalysis Radiation Data

ZHANG Qiong, QIAN Yong fu   

  1. Department of Atmospheric Sciences, Nanjing University, Nanjing 210093
  • Received:1998-03-18 Revised:1998-06-27 Online:1999-07-15 Published:1999-07-15
  • Supported by:
    National Natural Science Foundation of China,No.49635190

摘要: 本文利用1979年~1995年17年平均的NCEP/NCAR(National Center for Environmen-tal Prediction/National Centerfor Atmospheric Research,美国国家环境预报中心/美国国家大气研究中心)再分析辐射资料估算了全球月平均地表反照率。从所得结果的时空分布来看,用NCEP/NCAR辐射资料得到的全球地表反照率基本上正确反映了地球表面下垫面类型的分布特性及其变化。纬向平均分布显示了全球地表反照率具有明显的年变化,与其它类似工作相比,除高纬度海表反照率略为偏高外,其它地区的分布基本一致。用该资料得到的我国地表反照率也很好地表征了我国复杂的下垫面特性及其随季节的变化,其时空分布与国内其他作者的结果一致,部分地区数值上略为偏大,用1979年青藏高原气象科学试验观测资料验证后发现,NCEP/NCAR资料得到的青藏高原地区的地表反照率较其它资料更接近观测值。

关键词: 月平均地表反照率, NCEP/NCAR再分析资料, 时空分布, 年变化

Abstract: The 17 years mean (1979~1995) NCEP/NCAR reanalysis radiation data are used to estimate the global monthly mean surface albedo. For clear sky conditions, the monthly mean surface albedo can be obtained by the ration of monthly mean reflected radiant flux and monthly mean total radiant flux at surface, and a correction is applied which takes account of the effect of solar zenith angle. The results show that the seasonal cycle and the spatial distribution of global surface albedo are correspondent to the characteristics and variations of the earth’s different underlying surface. The zonally averaged surface albedo shows an apparent annual variation. A comparison of the results of present method with other studies indicates that the values of sea surface albedo at high latitudes in this work tend to be slightly higher than the others. While the distribution of surface albedo in other regions are basically consistent to the others. The surface albedo in China also well represents the characteristics and seasonal cycle of complex underlying surface. Compared to the other similar works carried by Chinese scientists, the time and spatial distribution are accordant but the values in some regions are slightly higher. Verified by observation data of Qinghai Xizang (Tibetan) Plateau Meteorological Scientific Experiment in 1979, it is found that the surface albedo in the Qinghai Xizang (Tibetan) Plateau region obtained from the NCEP/NCAR data is closer to the observation data than the others. From the above results, it is suggested that the global monthly mean albedo estimated from the NCEP/NCAR can be applied into the global climate model, further correction for the albedo will depend on the sensitivity numerical experiment of the climate model.

Key words: monthly mean surface albedo, NCEP/NCAR reanalysis data, time and spatial distribution, annual variation

中图分类号: 

  • P422.15