干旱区研究 ›› 2018, Vol. 35 ›› Issue (3): 597-605.doi: 10.13866/j.azr.2018.03.12

• 气候环境 • 上一篇    下一篇

新疆地区遥感、融合和陆面模式模拟的蒸散产品的不确定性分析

崔俊杰1,2,白洁1,郑磊1,2,李玉珍1,2,赵洪飞1,2,袁秀亮1,2,李龙辉1   

  1. (1.中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室,新疆 乌鲁木齐 830011;2.中国科学院大学,北京 100049)
  • 收稿日期:2017-10-13 修回日期:2017-11-01 出版日期:2018-05-15 发布日期:2018-06-01
  • 作者简介:崔俊杰(1992-),女,硕士研究生,主要从事陆面模式和遥感蒸散产品的应用. E-mail:cuijunjie15@mails.ucas.ac.cn
  • 基金资助:
    国家自然科学基金委员会-新疆联合基金“本地优秀青年人才培养专项”(U1403382);新疆维吾尔自治区重点实验室开放课题(2016D03004)资助

Uncertainty of Evapotranspiration Products Based on Fusion of Multi-source Remote Sensing Data and Land Surface Modes in Xinjiang

CUI Jun-jie1,2, BAI Jie1, ZHENG Lei1,2, LI Yu-zhen1,2, ZHAO Hong-fei1,2, YUAN Xiu-liang1,2, LI Long-hui1   

  1. (1. State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China;2. University of Chinese Academy of Sciences, Beijing 100049, China)
  • Received:2017-10-13 Revised:2017-11-01 Online:2018-05-15 Published:2018-06-01
  • Contact: 白洁. E-mail:baijie@ms.xjb.ac.cn

摘要: 蒸散是干旱区水资源消耗的主要方式,由于该地区地表植被覆盖稀疏且空间异质性较大,目前国际常用的众多蒸散产品的结果存在较大差异。故选取中分辨率成像光谱仪(MOD16)蒸散产品、全球陆地蒸散阿姆斯特丹模型(Global Land Evapotranspiration Amsterdam Model,GLEAM)和通用陆面模式(Common Land Model,CoLM)的蒸散产品为代表,利用三角帽(Three Cornered Hat,TCH)方法定量评价3种蒸散产品在新疆干旱区模拟结果的空间不确定性。结果表明:GLEAM和MOD16蒸散产品的空间分布规律相似,山区蒸散值均显著高于平原区;CoLM在阿勒泰山、天山蒸散值显著高于平原区。此外,全疆多年平均蒸散值分别为:GLEAM[(142.36±11.11)mm·a-1]、CoLM[(126.66±19.12)mm·a-1]、MOD16[(78.64±4.61)mm·a-1]。基于TCH方法的全疆蒸散模拟的不确定性结果大小依次为:CoLM(24.18 mm·a-1),GLEAM蒸散产品(21.58 mm·a-1),MOD16蒸散产品(17.66 mm·a-1)。在灌丛,山地半干旱区和山地半湿润区,3种蒸散产品的不确定性显著不同,其中CoLM不确定性最大(33.47 mm·a-1、30.46 mm·a-1、32.11 mm·a-1),MOD16不确定性最小(9.50 mm·a-1、14.80 mm·a-1、14.34 mm·a-1)。量化新疆地区蒸散的不确定性为更加准确估算该地的蒸散有着重要的科学意义。

关键词: 不确定性分析, 蒸散量, TCH方法, 陆面模式, 遥感模型, 新疆地区

Abstract:

Evapotranspiration (ET) is an indispensable part of water resources consumption in arid region, and it is also one of the key indicators used for assessing water resources. As the vegetation here is extremely sparse and has relatively high spatial heterogeneity, it is a challenge to accurately estimate ET in arid region. Most of the common ET products based on fusion of multi-source remote sensing data and land surface modes showed the different ET results in arid region. The results of different ET products with eddy covariance (EC) measurements were generally compared in previous studies, but the issues of spatial scale mismatch between EC data and ET products are unresolved yet. It is difficult to obtain the true values of ET in large scale. The sources of uncertainty may be from the different model structures, calculation methods, forcing datasets, and so on. In this paper, three Cornered Hat (TCH) methods without requiring a priori knowledge of the observed ET values were used to estimate the uncertainties of ET output in Xinjiang based on the Common Land Model (CoLM), Global Land Evapotranspiration Amsterdam Model (GLEAM) and Moderate Resolution Imaging Spectroradiometer ET products (MOD16). The results showed that the spatial patterns of GLEAM and MOD16 ET products were similar, and the ET values in the mountains were significantly higher than that in the plains. The ET values of CoLM in the Altay and Tianshan mountains were significantly higher than that in the plains. In addition, the mean annual ET values in Xinjiang during the period from 2000 to 2014 differed markedly, and they were 142.36±11.11 mm·a-1, 126.66±19.12 mm•a-1 and 78.64±4.61 mm·a-1 obtained by the GLEAM, CoLM and MOD16 respectively. The CoLM and MOD16 products revealed that there was no significant decrease trend in ET during the period from 2000 to 2014 (-1.03 mm•a-1 and -0.24 mm•a-1 respectively, P> 0.05). The GLEAM product showed that there was no significant increase trend in ET (0.02 mm·a-1, P> 0.05). The uncertainty based on the TCH method of CoLM was the highest (24.18 mm•a-1) in Xinjiang, that based on the GLEAM was moderate (21.58 mm•a-1), and that based on the MOD16 was the lowest (17.66 mm•a-1). In the shrub lands, Tianshan Mountains and semi-humid region, the uncertainties of CoLM (33.47, 30.46 and 32.11 mm/a) were significantly higher than those of GLEAM (28.31, 24.73 mm•a-1 and 24.19 mm·a-1) and of MOD16 (9.50, 14.80 mm•a-1 and 14.34 mm•a-1). It was crucial to quantify the uncertainty of regional ET based on the CoLM, GLEAM and MOD16 ET products for accurately estimating water consumption and providing appropriate ET product for long-term water cycle change in Xinjiang. The method used in this paper might provide a reference for analyzing the uncertainty.

Key words: uncertainty, evapotranspiration, Cornered Hat method, land surface mode, remote sensing data