2017 , Vol. 19 >Issue 1: 101 - 109

Orginal Article

An Algorithm of Snow Cover Fraction Retrieval Considering the Variability of Snow Particle Size

• WANG Jie , 1 ,
• HUANG Chunlin , 2, * ,
• HAO Xiaohua 2
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• 1. College of Land and Resources, China West Normal University, Nanchong 637009,China
• 2. Cold and Arid Regions Environmental and Engineering Research Institute, ChineseAcademy of Sciences, Lanzhou 730000, China
*Corresponding author: HUANG Chunlin, E-mail:

Request revised date: 2016-06-19

Online published: 2017-01-13

《地球信息科学学报》编辑部 所有

Abstract

WANG Jie , HUANG Chunlin , HAO Xiaohua . An Algorithm of Snow Cover Fraction Retrieval Considering the Variability of Snow Particle Size[J]. Journal of Geo-information Science, 2017 , 19(1) : 101 -109 .

4 CLSUnSAL算法雪粒径与积雪面积反演

Marian-Daniel Iordache采用协同稀疏回归框架（也叫多任务,或者称为同时性,CLSUnSAL算法）来提高混合像元分解的精度[14]。CLSUnSAL算法的基本公式如式（1）所示。
$min a ( 1 / 2 ) EA - Y 2 2 + λ ∑ k = 1 p a k 2$ （1）

$NDSI = R 2 - R 6 R 2 + R 6 （ NDSI ≥ 0.2 ）$ （2）

Fig.5 The retrieved snow grain sizes of Zege model for MOD09GA images

$SFC = f 1 + f 1 f 1 + f 2 + f 3 ( f 12 + f 11 + f 13 )$ （3）

Tab.1 The accuracy statistics of different models for snow cover fraction retrieval

Non-CLSUnSAL 0.2500 0.520 0.7776
Norm-CLSUnSAL 0.1820 0.570 0.9949
MOD10A1 0.1954 0.569 1.0250

6 结论与展望

（1）本文提出的解混模型不仅考虑了积雪端元的变化,还考虑了积雪端元与其他端元的二次交互过程,能更有效地刻画积雪的物理过程。
（2）本文提出的解混模型相比MODSCAG模型,具有更高的运行效率。其采用渐进辐射传输模型动态地建立不同粒径大小的雪反射率光谱库,有利于加速程序的运行。
（3）通常情况下,利用辐射传输模型建立的雪反射率光谱库与遥感影像上的积雪光谱不在一个尺度上,会导致光谱完全不匹配。为了减弱光谱之间的不匹配,本文采用了L2范数规则化,从Non-CLSUnSAL与Norm-CLSUnSAL模型获取的积雪面积可知,L2范数规则化具有非常重要的意义。

The authors have declared that no competing interests exist.

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