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Daily High-Resolution Land Surface Freeze/Thaw Detection Using Sentinel-1 and AMSR2 Data

Jian Wang, Lingmei Jiang, Kimmo Rautiainen, Cheng Zhang, Zhiqiang Xiao, Heng Li, Jianwei Yang, Huizhen Cui
2022 Remote Sensing  
The overall accuracy of this daily 1 km F/T is more than 88.1% when evaluated with the in situ 5 cm soil temperature over China and Canada.  ...  Currently, large-scale, high-resolution F/T detection is restricted by low spatial resolution of passive microwave remote sensing sensors or low temporal resolution of synthetic aperture radar (SAR) data  ...  Three in situ soil moisture and temperature observation networks, including the Genhe watershed, Saihanba, and Naqu, are located in China (Figure 1c -e), and another in situ soil moisture and temperature  ... 
doi:10.3390/rs14122854 fatcat:lph35jnaazd4th3rkvumqxeiv4

Evaluation of the SMOS and SMAP soil moisture products under different vegetation types against two sparse in situ networks over arid mountainous watersheds, Northwest China

Lanhui Zhang, Chansheng He, Mingmin Zhang, Yi Zhu
2019 Science China. Earth Sciences  
This study presents evaluation of the SMOS (L2) and SMAP (L2_P_E and L2_P) products against ground-based observations from the Upstream of the Heihe River Watershed in situ Soil Moisture Network (UHRWSMN  ...  Results show that all the three products are reliable in catching the temporal trend of the in situ observations at both point and watershed scales in the study area.  ...  Temporal stability analysis The temporal stability analysis has also been conducted in this study because it reflects the tempo-spatial distribution of soil moisture with little dependence on the absolute  ... 
doi:10.1007/s11430-018-9308-9 fatcat:fdin33amwnekhno2ettm4t3p64

Multi-Scale Evaluation of the SMAP Product Using Sparse In-Situ Network over a High Mountainous Watershed, Northwest China

Lanhui Zhang, Chansheng He, Mingmin Zhang
2017 Remote Sensing  
Results show that, compared with in situ observations at point scale, both the L3 and L4 products represent the temporal trends of the in situ observations in the study area well, with R values of 0.601  ...  and spatial scales; and the L3 product provides more reliable soil moisture estimates in the study area.  ...  Temporal Stability Analysis The temporal stability analysis is applied in this study because it is less influenced by sampling size and not so much dependent on the absolute values of soil moisture, but  ... 
doi:10.3390/rs9111111 fatcat:jx7hkkvoynfvjlvgkt2uppdsca

Performance of multi-source passive microwave soil moisture products in maize cultivation areas of Northeast China

Xingming Zheng, Zhuangzhuang Feng, Hongxin Xu, Yanlong Sun, Yu Bai, Lei Li, Bingze Li, Xiaowei Zhao, Rui Zhang, Tao Jiang, Xiaojie Li, Xiaofeng Li
2020 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
In this study, a ground-based wireless sensor network with 28 observation nodes that were spatially distributed within 36 × 36 km was established to achieve satellite-scale "true" SM values through sensor  ...  Passive microwave remote sensing is an effective way to obtain global soil moisture (SM) measurements, and many studies have explored the uncertainty inherent in microwave-based SM products.  ...  ACKNOWLEDGMENT The authors would like to thank the Changchun Jingyuetan remote sensing test site and the Chinese Academy of Sciences for providing ground soil moisture data.  ... 
doi:10.1109/jstars.2020.2995623 fatcat:esdowwk6wna3fd5yigiyj33a3a

Evaluation of SMAP, SMOS and AMSR2 soil moisture products based on distributed ground observation network in cold and arid regions of China

Zengyan Wang, Tao Che, Tianjie Zhao, Liyun Dai, Xiaojun Li, Jean Pierre Wigneron
2021 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
Long-term surface soil moisture (SM) data are increasingly needed in water budget and energy balance analysis of watersheds.  ...  The performance of nine remotely sensed SM products from AMSR2, SMOS and SMAP missions, are evaluated based on observations collected from distributed observation networks in the Heihe River Basin (HRB  ...  Ground Observation Networks As shown in Fig.1 , three nested soil moisture observation networks are established throughout HRB during the HiWATER field campaigns [33] , namely the hydrometeorological  ... 
doi:10.1109/jstars.2021.3108432 fatcat:rdiznt3ypvhoxbsbdmxdqajve4

Ground, Proximal and Satellite Remote Sensing of Soil Moisture

Ebrahim Babaeian, Morteza Sadeghi, Scott B. Jones, Carsten Montzka, Harry Vereecken, Markus Tuller
2019 Reviews of Geophysics  
Soil moisture (SM) is a key hydrologic state variable that is of significant importance for numerous Earth and environmental science applications that directly impact the global environment and human society  ...  needs and directions to further advance and optimize technology, analysis and retrieval methods, and the application of SM information to improve the understanding of critical zone moisture dynamics.  ...  SM = soil moisture; RMSE = root-mean-square error; SMAP = Soil Moisture Active Passive; SCAN = Soil Climate Analysis Network; OK = Oklahoma; SMOSMANIA = Soil Moisture Observing System - Louvet et al.  ... 
doi:10.1029/2018rg000618 fatcat:hcfa2uqiz5ffnf7o3fijc6rnwu

Assessing Land Cover and Ecological Quality Changes in the Forest-Steppe Ecotone of the Greater Khingan Mountains, Northeast China, from Landsat and MODIS Observations from 2000 to 2018

Fang Shi, Mingxing Liu, Jie Qiu, Yali Zhang, Huiyi Su, Xupeng Mao, Xin Li, Jiahui Fan, Junsong Chen, Yingying Lv, Wanggu Xu, Zhi Wang (+1 others)
2022 Remote Sensing  
To measure the effect of ecological protection in recent years, Landsat images, object-oriented image segmentation, and convolutional neural networks were used to create land cover datasets of the forest-steppe  ...  These observations indicate that the ecological quality has gradually improved due to the strict protection of forest and grassland resources and the suppression of desertification.  ...  Seasonal snowpack substantially influences the regional water stress gradient and interannual variation in NPP by affecting the soil moisture in the next growing season [72] .  ... 
doi:10.3390/rs14030725 fatcat:nbf7cgqb3fcqdp36youzo75z4u

Segmentation of multi-temporal polarimetric SAR data based on mean-shift and spectral graph partitioning

Caiqiong Wang, Lei Zhao, Wangfei Zhang, Xiyun Mu, Shitao Li
2022 PeerJ  
For this, a new algorithm for multi-temporal PolSAR image segmentation is proposed in this paper.  ...  For the targets with time series changes, the single-temporal PolSAR image segmentation algorithm is difficult to provide correct segmentation results for its target recognition, time series analysis and  ...  The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.  ... 
doi:10.7717/peerj.12805 pmid:35186456 pmcid:PMC8845569 fatcat:qx6axxrsevbanbo4nusyegzyby

Agricultural drought management in Northeast China and Inner Mongolia 中国東北部と内モンゴルにおける農業干ばつの管理

Li Rui
2015 unpublished
In a previous study, Zipporah (2011) investigated the temporal aspects of drought in Africa based on NDVI and Owe's AMSR-E soil moisture dataset, using correlation analysis and a distributed lag model  ...  Gu et al. (2008) evaluated the temporal relationship between soil moisture data and NDVI at 10 homogeneous grassland sites; at 7 of the sites there was a 1-to 2-week time lag in the NDVI response to soil  ...