This dataset contains measurements of L-band brightness temperature by an ELBARA-III microwave radiometer in horizontal and vertical polarization, profile soil moisture and soil temperature, turbulent heat fluxes, and meteorological data from the beginning of 2016 till August 2019, while the experiment is still continuing. Auxiliary vegetation and soil texture information collected in dedicated campaigns are also reported. This dataset can be used to validate the Soil Moisture and Ocean Salinity (SMOS) and Soil Moisture Active Passive (SMAP) satellite based observations and retrievals, verify radiative transfer model assumptions and validate land surface model and reanalysis outputs, retrieve soil properties, as well as to quantify land-atmosphere exchanges of energy, water and carbon and help to reduce discrepancies and uncertainties in current Earth System Models (ESM) parameterizations. ELBARA-III horizontal and vertical brightness temperature are computed from measured radiometer voltages and calibrated internal noise temperatures. The data is reliable, and its quality is evaluated by 1) Perform ‘histogram test’ on the voltage samples (raw-data) of the detector output at sampling frequency of 800 Hz. Statistics of the histogram test showed no non-Gaussian Radio Frequency Interference (RFI) were found when ELBAR-III was operated. 2) Check the voltages at the antenna ports measured during sky measurements. Results showed close values. 3) Check the instrument internal temperature, active cold source temperature and ambient temperature. 3) Analysis the angular behaviour of the processed brightness temperatures. -Temporal resolution: 30 minutes -Spatial resolution: incident angle of observation ranges from 40° to 70° in step of 5°. The area of footprint ranges between 3.31 m^2 and 43.64 m^2 -Accuracy of Measurement: Brightness temperature, 1 K; Soil moisture, 0.001 m^3 m^-3; Soil temperature, 0.1 °C -Unit: Brightness temperature, K; Soil moisture, m^3 m^-3; Soil temperature, °C/K
Bob Su, WEN Jun
This dataset contains 18 years (2002-2020) global spatio-temporal consistent surface soil moisture . The resolution is 36 km at daily scale, the projection is EASE-Grid2, and the data unit is m3 / m3. This dataset adopts the soil moisture neural network retrieval algorithm developed by Yao et al. (2017). This study transfers the merits of SMAP to AMSR-E/2 through using an Artificial Neural Network (ANN) in which SMAP standard SSM products serve as training targets with AMSR-E/2 brightness temperature (TB) as input. Finally, long term soil moisture data are output. The accuracy is about 5% volumetric water content. (evaluation accuracy of 14 dense ground network globally.)
YAO Panpan, LU Hui
Vegetation photosynthesis is a key component of carbon cycle in terrestrial ecosystem. Simulating photosynthesis activities on different spatial and temporal scales is helpful to solve the problem of land carbon budget, and it is also an important way to accurately predict the direction of future climate change and an important prerequisite for scientific understanding of the supporting capacity of terrestrial ecosystem for sustainable development of human society. At present, although a variety of algorithms and products for estimating the total primary productivity (GPP) of ecosystems have been relatively mature, there are still great differences and uncertainties in the global GPP products of long time series, especially the trend of their temporal variation. Sunlight induced chlorophyll fluorescence (SIF) remote sensing is a new type of remote sensing technology developed rapidly in recent years. The close relationship between SIF and photosynthetic process makes it an effective probe to indicate the changes of vegetation photosynthesis and a powerful means to monitor GPP. A new vegetation index (Nirv) based on remote sensing data, namely the product of normalized vegetation index (NDVI) and near-infrared reflectance, is highly related to remote sensing SIF products; based on mechanism derivation, model simulation and analysis of remote sensing data, Nirv can be used as an alternative product of SIF to estimate global GPP. Therefore, on the basis of analyzing the feasibility of Nirv as SIF and GPP probe, this data set generates the global high-resolution long-time series GP data from 1982 to 2018 based on the AVHRR data of remote sensing and hundreds of flux stations around the world, and analyzes the temporal and spatial variation trend of global GPP. The resolution is month, 0.05 degree, and the data unit is gcm-2 The annual average global GPP is about 128.3 ± 4.0 PG Cyr − 1, and the root mean square error (RMSE) of the data is 1.95 gcm-2 D-1. The data set can be used to study global climate change and carbon cycle.
WANG Songhan, ZHANG Yongguang
Based on Landsat data (kh-9 data in 1976 as auxiliary data), glacial lake data of nearly 40 years (1970s-2018) in the western Nyainqentanglha range were obtained by manual digitization and visual interpretation. The variation characteristics of glacial lake over 0.0036 square kilometers in terms of type, size, elevation and watershed were analyzed in detail. The results show that, between 1976 and 2018, the number of glacial lakes increased by 56% from 192 to 299 and their total area increased by 35% from 6.75 ± 0.13 square kilometers to 9.12 ± 0.13 square kilometers ; the type of glacial lake is changing obviously; the smaller glacial lake is changing faster; the expansion of glacial lake is developing to higher altitude.
LUO Wei, ZHANG Guoqing
This dataset contains daily 0.05°×0.05° land surface soil moisture products in Qilian Mountain Area in 2018. The dataset was produced by utilizing the multivariate statistical regression model to downscale the “AMSR-E and AMSR2 TB-based SMAP Time-Expanded Daily 0.25°×0.25° Land Surface Soil Moisture Dataset in Qilian Mountain Area (SMsmapTE, V1)”. The auxiliary datasets participating in the multivariate statistical regression include GLASS Albedo/LAI/FVC, 1km all-weather surface temperature data in western China by Ji Zhou and Lat/Lon information.
CHAI Linna, ZHU Zhongli, LIU Shaomin
This data set includes the monthly average actual evapotranspiration of the Tibet Plateau from 2001 to 2018. The data set is based on the satellite remote sensing data (MODIS) and reanalysis meteorological data (CMFD), and is calculated by the surface energy balance system model (SEBS). In the process of calculating the turbulent flux, the sub-grid scale topography drag parameterization scheme is introduced to improve the simulation of sensible and latent heat fluxes. In addition, the evapotranspiration of the model is verified by the observation data of six turbulence flux stations on the Tibetan Plateau, which shows high accuracy. The data set can be used to study the characteristics of land-atmosphere interaction and the water cycle in the Tibetan Plateau.
HAN Cunbo, MA Yaoming, WANG Binbin, ZHONG Lei, MA Weiqiang*, CHEN Xuelong, SU Zhongbo
This data set includes land cover classification products of 30 meters in Qilian mountain area from 1985 to 2019. Firstly, the product uses Landsat-8/OLI to construct the 2015 time series data. According to the different NDVI time series curves of various ground features, the knowledge of different features is summarized, the rules are set to extract different features, and the land cover classification map in 2015 is obtained. The classification system refers to IGBP classification system and from_ LC classification system can be divided into 10 categories: cultivated land, woodland, grassland, shrub, wetland, water body, impervious surface, bare land, glacier and snow. According to the accuracy evaluation of Google Earth HD images and field survey data, the overall accuracy of land cover classification products in 2015 was as high as 92.19%. Based on the land cover classification products in 2015, based on the Landsat series data and strong geodetic data processing ability of Google Earth engine platform, the land cover classification products from 1985 to 2019 are produced by using the idea and method of change detection. By comparing the classification products, it is concluded that the land cover classification products based on Google Earth engine platform have good consistency with the classification products based on time series method. In short, the land cover data set in the core area of Qilian Mountain has high overall accuracy, and the method based on Google Earth engine platform sample training can expand the existing classification products in time and space, and can reflect more land cover type change information in a long time series.
YANG Aixia, ZHONG Bo, JUE Kunsheng, WU Junjun
This dataset contains daily 0.01°×0.01° land surface soil moisture products in the Qinghai-Tibet Plateau in 2005, 2010, 2015, 2017, and 2018. The dataset was produced by utilizing the multivariate statistical regression model to downscale the “SMAP Time-Expanded 0.25°×0.25° Land Surface Soil Moisture Dataset in the Qinghai-Tibet Plateau (SMsmapTE, V1)”. The auxiliary datasets participating in the multivariate statistical regression include GLASS Albedo/LAI/FVC, 1km all-weather surface temperature data in western China by Ji Zhou, and Lat/Lon information.
CHAI Linna, ZHU Zhongli, LIU Shaomin
This dataset contains land surface soil moisture products with SMAP time-expanded daily 0.25°×0.25°in Qinghai-Tibet Plateau Area. The dataset was produced based on the Random Forest method by utilizing passive microwave brightness temperature along with some auxiliary datasets. The temporal resolution of the product in 1980,1985,1990,1995 and 2000 is monthly, by using SMMR, SSM/I, and SSMIS brightness temperature from 19 GHz V/H and 37 GHz V channels. The temporal resolution of the product between June 20, 2002 and Dec 30, 2018 is daily, by utilizing AMSR-E and AMSR2 brightness temperature from 6.925 GHz V/H, 10.65 GHz V/H, and 36.5 GHz V channels. The auxiliary datasets participating in the Random Forest training include the IGBP land cover type, GTOPO30 DEM, and Lat/Lon information.
CHAI Linna, ZHU Zhongli, LIU Shaomin
This data set includes the distribution products of 30 m cultivated land and construction land in Qilian mountain area from 1985 to 2019. The product comes from the land cover classification products of 30m in Qilian mountain area from 1985 to 2019. NDVI products, light data products, DEM products and SAR data of sentry 1 are used in the production of the products. The total accuracy of the product is better than 85%. Among them, the peoducts from 1985-2015 have a 5 year- time resolution, and the other products have a 1 year - time resolution.
YANG Aixia, ZHONG Bo, JUE Kunsheng, WU Junjun
The land cover dataset of Pan third pole major cities contains 14 cities (Urumqi, Xining, Lanzhou, Dhaka, Kathmandu, Lucknow, Delhi, Lahore, Islamabad, Kabul, Dushanbe, Tashkent, Bishkek and Almaty) in 2000 / 2010 / 2017, the spatial resolution of this dataset is 30 m. It includes vegetation, cultivated land, artificial surface, water body and others. Based on globeland30, mcd12q1 and globcover2009, the consistent regions were identified and retained. The inconsistent regions were reclassified by deep learning method, and the final classification results were obtained by fusing the above regions. The data has been verified by visual interpretation. The data are applied to the study of construction land dynamics and anthropogenic influence in Pan-Third Pole cities. Data type: grid. Projection mode: UTM projection.
Xin LI, Wenfei LUAN
Vulnerability assessment dataset of hectometre level for 34 key nodes assessment the flood risk of key nodes in the Belt and Road under the extreme precipitation events, in order to provide basis for decision-making for the local government department, at the same time before flood disaster early warning, which may take the disaster prevention and mitigation measures for the precious time, reduce people's lives and property damage brought by the flood. Based on the data of GDP, population, land ues, road density and river density in the Belt and Road, this dataset combined with the methods of spatial analysis of ArcGIS, assigning different weights to each indicator and building assessment 34 key nodes under the condition of extreme precipitation in flood vulnerability level, which was divided into 5 levels by using natural break point method, representing no vulnerability, low vulnerability, middle vulnerability, high vulnerability, extreme high vulnerability, respectively.
GE Yong, LI Qiangzi, LI Yi
The pan third pole historical extreme precipitation data set includes 2000-2018 extreme precipitation identification data. One belt, one road, was used to assess the rainfall in the important area along the GPM IMERG Final Run (GPM) daily rainfall. The extreme precipitation threshold of 34 important nodes was evaluated by percentile method. The daily precipitation period was identified by the calculated threshold, and the surface inundation area was produced on the basis of extreme precipitation. The data range mainly includes 34 key nodes of Pan third pole (Vientiane, Alexandria, Yangon, Calcutta, Warsaw, Karachi, yekajerinburg, Chittagong, Djibouti, etc.) The data set can provide the basis for local government decision-making, so as to correctly identify extreme precipitation and reduce the loss of life and property caused by extreme precipitation.
This data set includes the normalized vegetation index, vegetation coverage, vegetation net primary productivity, grassland biomass, forest stock vegetation parameter remote sensing products in the key area of Qilian mountain from May 2019 to October 2019, and the spatial resolution is 10m. In this data set, remote sensing data sources such as GF-1, GF-6, Sentinel-2, and ZY-3, combined with basic meteorological and ground monitoring data, are used to retrieve vegetation parameters such as band ratio method, mixed pixel decomposition model and CASA model to generate monthly vegetation index remote sensing products of Qilian Mountain in the growing season. This data set provides data support for the diagnosis of regional eco-environmental problems and the dynamic assessment of eco-environment by constructing a high spatial-temporal resolution eco-environmental monitoring data set based on high-resolution satellites.
QI Yuan, ZHANG Jinlong, CAO Yongpan, ZHOU Shengming, WANG Hongwei
This data set is the human activity data of Qilian Mountain in 2019. Based on the data of mining, illegal house renovation, new roads, land leveling and ecological restoration in Qilian Mountains, the high-resolution remote sensing images to compare the changes before and after statistical analysis. In the Qilian Mountains area, the changes of land types are investigated and verified block by block; in the areas with suspicious maps, re-interpretation and verification; in the areas with unreflecting images, field verification is carried out to collect relevant data, check and correct the location. At the same time, it further checks the attribute information of mining, illegal house renovation, new roads, land leveling and ecological restoration in the Qilian Mountains in 2019, and unifies the input and editing of the patches and their attributes, forming the data set of human activities in the Qilian Mountains in 2018, realizing the current situation and timeliness of ecological management in the Qilian Mountains, and providing data support for the monitoring of human activities in Qilian Mountains in 2019.
QI Yuan, ZHANG Jinlong, ZHOU Shengming, LI Na, WANG Hongwei
Land surface temperature is a critical parameter in land surface energy balance. This dataset provides the monthly land surface temperature of UAV remote sensing for typical ground stations in the middle reaches of Heihe River basin from July to September in 2019. The land surface temperature retrieval algorithm is an improved single-channel algorithm, which was applied to the land surface brightness temperature data obtained by the UAV thermal infrared remote sensing sensor, and finally the land surface temperature data with a spatial resolution of 0.4m was obtained.
ZHOU Ji, LIU Shaomin, WANG Ziwei
Surface albedo is a critical parameter in land surface energy balance. This dataset provides the monthly land surface albedo of UAV remote sensing for typical ground stations in the middle reaches of Heihe river basin during the vegetation growth stage in 2019. The algorithm for calculating albedo is an empirical method, which was developed based on a comprehensive forward simulation dataset based on 6S model and typical spectrums. This method can effectively transform the surface reflectance to the broadband surface albedo. The method was then applied to the surface reflectance acquired by UAV multi-spectral sensor and the broadband surface albedo with a 0.2-m spatial resolution was eventually obtained.
ZHOU Ji, LIU Shaomin, DONG Weishen
This data set includes the normalized vegetation index, vegetation coverage, vegetation net primary productivity, grassland biomass, forest stock vegetation parameters of the Heihe River Basin from May 2019 to October 2019, and the spatial resolution is 10m. In this dataset, remote sensing data sources such as GF-1, GF-6, Sentinel-2, and ZY-3, combined with basic meteorological and ground monitoring data, are used to retrieve vegetation parameters such as band ratio method, mixed pixel decomposition model and CASA model to generate monthly vegetation index remote sensing products of Qilian Mountain in the growing season. This data set provides data support for the diagnosis of regional eco-environmental problems and the dynamic assessment of eco-environment by constructing a high spatial-temporal resolution eco-environmental monitoring data set based on high-resolution satellites.
QI Yuan, ZHANG Jinlong, CAO Yongpan, ZHOU Shengming, WANG Hongwei
NDVI is a very important vegetation index for the research of vegetation growth and land cover classification. This dataset provides a monthly land surface albedo of UAV remote sensing with a spatial resolution of 0.2 m. It measured in the midstream of Heihe River Basin during the vegetation growth season over typical stations in 2019. The pix4D mapper software was used for image mosaic and NDVI calculation.
ZHOU Ji, LIU Shaomin, JIN Zichun
Snow pits were observed daily at Altay base station（lon：88.07、lat: 44.73） from November 27, 2015 to March 26, 2016. Parameters include: snow stratification, stratification thickness, density, particle size, temperature. The frequency of observation was daily. The particle size was observed by a microscope with camera, the density was observed by snowfork, snow shovel and Snow Cone, and the temperature was automatically observed by temperature sensor. The observation time was 8:00-10:100 am local time. The snow particle size is observed according to the natural stratification of snow. The snow particles of each layer are collected, and at least 2 photos are taken. The long axis and short axis of at least 10 groups of particles are measured by corresponding software. Unit: mm. The density was observed at equal intervals, snowfork every 5 cm, snow shovel every 10 cm, snow cone to observe the density of the whole snow layer, and the density of each layer was observed three times. The unit is g / cm3. The height of temperature observation is 0cm, 5cm, 10cm, 15cm, 25cm, 35cm, 45cm, 55cm. The recording frequency was once every 1 minute. The unit is OC.