The dataset of airborne microwave radiometers (L&K) mission was obtained in the Biandukou flight zone on Mar. 21, 2008. The frequency of L bands was 1.4 GHz with back sight of 35 degree and dual polarization (H&V) was acquired; and the frequency of K band was 18.7 GHz at the nadir view angle without polarization. The plane took off at Zhangye airport at 8:00 (BJT) and landed at 11:40, from north to south along the scheduled lines at the altitude about 4100m (400m for the low flight) and speed about 290km/hr . The raw data include microwave radiometer (L&K) data and GPS data; the former were instantaneous non-imaging observation recorded in text, which could be converted into brightness temperatures according to the calibration coefficients (filed with raw data together), and the latter were aircraft longitude, latitude and attitude. Moreover, based on the respective real-time clock log, observations by the microwave radiometer and GPS can be integrated to offer coordinates matching for the former. Yaw, flip, and pitch motions of aircraft were ignored due to the low resolution of microwave radiometer observations. Observation information can also be rasterized, as required, after calibration and coordinates matching. L&K bands resolution (x) and footprint can be approximately estimated as x=0.3H (H is relative flight height) for L and x=0.24H for K.
0 2019-05-23
Based on the data of 21 regular meteorological observation stations in Heihe River Basin and its surrounding areas and 13 national benchmark stations around Heihe River provided by the data management center of Heihe plan, the daily sunshine hours are statistically sorted out and the monthly sunshine hours data of 1961-2010 for many years are calculated. The spatial stability analysis is carried out to calculate the variation coefficient. If the variation coefficient is greater than 100%, the geographical weighted regression is used to calculate the relationship between the station and the geographical terrain factors, and the monthly sunshine hours distribution trend is obtained; if the variation coefficient is less than or equal to 100%, the ordinary least square regression is used to calculate the sunshine hours and the geographical terrain factors (longitude, latitude, elevation, slope, aspect, etc.) of the station ）The distribution trend of sunshine hours per month is obtained, and the residuals after removing the trend are fitted and corrected by HASM (high accuracy surface modeling method). Finally, the monthly average sunshine hours distribution of the Heihe River Basin in 1961-2010 is obtained by adding the trend surface results and the residual correction results. Time resolution: monthly average sunshine hours for many years from 1961 to 2010. Spatial resolution: 500M.
0 2020-03-28
As the third pole of the Earth, the Tibetan Plateau has a significant impact on regional and global weather and climate as a heat source in spring and summer. In order to explore the temporal and spatial variation characteristics of multi-scale thermal forcing in different time on the plateau, it is necessary to establish a set of plateau heat source (collection) data based on observation data of continuous and reliable long-term observation. Based on the meteorological elements (surface temperature, surface air temperature, wind speed at the height of 10m, daily cumulative precipitation, etc.) of the 80 (32) observation stations on the Tibetan Plateau from 1979 to 2016 (1960-2016) of China Meteorological Bureau, the sensible heat(SH) and latent heat(LH) was calculated. Meanwhile, using satellite data processing to obtain the net radiation flux (RC) from 1984 to 2015 on the plateau, and then a set of quality controlled long-term plateau heat source data was obtained. This data set considers the diurnal variation of the overall heat transfer coefficient when calculating the surface sensible heat flux.
0 2020-10-12
The land use / land cover data set of Heihe River Basin in 2011 is the Remote Sensing Research Office of Institute of cold and drought of Chinese Academy of Sciences. Based on the remote sensing data of landsatm and ETM in 2011, combined with field investigation and verification, a 1:100000 land use / land cover image and vector database of Heihe River Basin is established. The main contents include: 1:100000 land use graph data and attribute data of Heihe River Basin. The land cover data of 1:100000 (2011) in Heihe River Basin and the previous land cover are classified into six first-class categories (cultivated land, forest land, grassland, water area, urban and rural residents, industrial and mining land and unused land) and 25 second-class categories by the same hierarchical land cover classification system. The data type is vector polygon and stored in shape format. This data respects the opinion of the data author, and cannot share the whole basin data temporarily. Please indicate the research scope and exact purpose on the data application.
0 2020-03-08
Snow is a significant component of the ecosystem and water resources in high-mountain Asia (HMA). Therefore, accurate, continuous, and long-term snow monitoring is indispensable for the water resources management and economic development. The present study improves the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Terra and Aqua satellites 8 d (“d” denotes “day”) composite snow cover Collection 6 (C6) products, named MOD10A2.006 (Terra) and MYD10A2.006 (Aqua), for HMA with a multistep approach. The primary purpose of this study was to reduce uncertainty in the Terra–Aqua MODIS snow cover products and generate a combined snow cover product. For reducing underestimation mainly caused by cloud cover, we used seasonal, temporal, and spatial filters. For reducing overestimation caused by MODIS sensors, we combined Terra and Aqua MODIS snow cover products, considering snow only if a pixel represents snow in both the products; otherwise it is classified as no snow, unlike some previous studies which consider snow if any of the Terra or Aqua product identifies snow. Our methodology generates a new product which removes a significant amount of uncertainty in Terra and Aqua MODIS 8 d composite C6 products comprising 46 % overestimation and 3.66 % underestimation, mainly caused by sensor limitations and cloud cover, respectively. The results were validated using Landsat 8 data, both for winter and summer at 20 well-distributed sites in the study area. Our validated adopted methodology improved accuracy by 10 % on average, compared to Landsat data. The final product covers the period from 2002 to 2018, comprising a combination of snow and glaciers created by merging Randolph Glacier Inventory version 6.0 (RGI 6.0) separated as debris-covered and debris-free with the final snow product MOYDGL06*. We have processed approximately 746 images of both Terra and Aqua MODIS snow containing approximately 100 000 satellite individual images. Furthermore, this product can serve as a valuable input dataset for hydrological and glaciological modelling to assess the melt contribution of snow-covered areas. The data, which can be used in various climatological and water-related studies, are available for end users at https://doi.org/10.1594/PANGAEA.901821 (Muhammad and Thapa, 2019).
0 2020-06-23
The dataset of ground truth measurement synchronizing with ALOS PALSAR was obtained in the Linze grassland foci experimental area on Jun. 10, 2008. The data were in FBS mode and HH/HV polarization combinations, and the overpass time was approximately at 23:39 BJT. Observations were carried out in plots A, B, C, D and E, which were divided into 6×6 subsites, with each one spanning a 120×120 m2 plot. Soil gravimetric moisture, volumetric moisture, and soil bulk density after drying by the cutting ring and the mean soil temperature from 0-5cm by the probe thermometer were measured in A, B and C; the soil temperature, soil moisture, the loss tangent, soil conductivity, the real part and the imaginary part of soil complex permittivity by the POGO soil sensor, and the mean soil temperature from 0-5cm by the probe thermometer in D and E. Data were archived in Excel file. See WATER: Dataset of setting of the sampling plots and stripes in the foci experimental area of Linze station for more information.
0 2019-09-12
The data set include crop leaf chlorophyll content observed at four sample regions, that is the soil moisture control experimental field at Daman county, and the EC plots, the super station, and Shiqiao sample plots at Wuxing village in Zhangye city. 1) Objective Crop leaf chlorophyll content, a key biophysical parameter, was observed as model parameter or a priori knowledge for canopy radiative transfer model or eco-hydrological models. 2) Measuring instruments SPAD. 3) Measuring site a. the soil moisture control experimental field at Daman county, Twelve soil water treatments are set. The wheat leaf chlorophyll content for each treatment is measured on 17, 23 and 29 May, and 3, 9, 14 and 24 June, and 5 and 12 July. b. the EC site The maize leaf chlorophyll content at 14 EC site (EC-2,EC-3,EC-5,EC-6,EC-7,EC-8,EC-9, EC-10, EC-11, EC-12, EC-13, EC-14, EC-15, EC-16) are measured on 14, 21, 25 and 31 May, 7, 13, 23 and 28 June, 3, 13, 18 and 23 July, 3, 12 and 28 August. c. the Super Station The maize chlorophyll content at the super station is measured on 22 and 28 May, 5, 11, 18, and 25 June, and 1, 8, 15, 22 and 31 July, 9, 15 and 22 August, and 3 and 11 September. d. the Shiqiao sample site The maize chlorophyll content at the Shiqiao village is measured on 17, 22 and 28 May, 4, 11, 17 and 25 June, 1, 8, 15, 22, and 30 July, 8, 16 and 27 August, and 9 September. 4) Data processing The observational data was recorded in the sheets and reorganized in the EXCEL sheets. The time used in this dataset is in UTC+8 Time.
0 2019-09-15
The dataset of evapotranspiration observed by micro-lysimeter was obtained in the reed plot A, the alfalfa plot D and the barley plot E of the Linze grassland foci experimental area from May 28 to Jul. 12, 2008. Observations were carried out from 6:00-8:00 am and from 18:00-20:00 pm every day with exceptions on afternoons of Jun. 5, 8, 9, 13 and 24, mornings of Jun. 14 and Jul. 2, the whole day from Jun. 16 to Jul.8 (alfalfa plot) and from Jun. 21 to 22 (the reed plot.) For more details, see Readme file.
0 2019-05-23
This data is the dunhuang land use status map digitized from the drawings. This map is one of the key scientific and technological research projects of the seventh five-year plan of China: comprehensive remote sensing survey of shelterbelt in the third north, and one of the series maps of the type area of gan qingning. The information is as follows: * chief editor: wang yimou, * deputy chief editor: feng yusun, you xianxiang, shenyuan village *, qing painting: wang jianhua, yao fafen, Yang ping * drawing: feng yu-sun, yao fa-fen, wang jianhua, zhao yanhua, li weimin * cartographic unit: desert laboratory, Chinese academy of sciences * publishing house: xi 'an map publishing house 2. File format and naming The data is stored in ESRI Shapefile format, including the following layers: Dunhuang land use status map, rivers, roads, lakes, railways, residential land, reservoirs, desertification 3. Data fields and properties Type code land resource class (Land_type) 12. Irrigated field 31 Woodland 311 Woodland 312 Joe irrigation mixed forest land (tree-shurb mixed) 321 Shrub land (Shrub) Sparse shrub 33 Sparse woods In winter and spring of 4111 Meadow grassland, Meadow grassland in the spring and winter) 4112 winter and spring of salinization meadow grassland, Saline meadow grassland in the spring and winter) 4112 winter and spring of salinization meadow grassland, Saline meadow grassland in the spring and winter) In winter and spring of 4113 salt meadow grassland (Salty soil meadow grassland in the spring and winter) 4122 gritty desert grassland autumn grass (Gravely desert - steppe grassland in autumn and winter) 4124 mountain desert grassland winter and spring pastures (Mountainous desert - steppe grassland in winter and spring) 4134 four seasons mountain desert grassland, Mountainous desert steppe in four seasons) Sandy desert steppe in autumn and winter Gravely desert steppe in autumn and winter Earthy desert steppe in four seasons Alpine steppe in four seasons 51 Urban and town land 52 Village land 73 Reservoir and pond 74 Reed marshes Tidal flat 81 Desert land 82 Saline-alkali land 83 Marshes 84 Sandy land Sandy flat and dry valley 86 Bare land 87 Gobi Gobi 88 Exposed rock Flat sandy land Compound dunes Undulatory sand-overlying land Dunes and barchan chain The sand ridge (Longitudinal dune) Check dune
0 2020-06-11
The dataset contains all individual glacial storage (unit: km3) over the Qinghai-Tibetan Plateau in 1970s and 2000s. It is sourced from the resultant data of the paper entitled "Consolidating the Randolph Glacier Inventory and the Glacier Inventory of China over the Qinghai-Tibetan Plateau and Investigating Glacier Changes Since the mid-20th Century". The first draft of this paper has been completed and is planned to be submitted to Earth System Science Data journal. The baseline glacier inventories in 1970s and 2000s are the Randolph Glacier Inventory 4.0 dataset, and the Glacier Inventory of China, respectively. Based on the individual glacial boundaries extracted from the above-mentioned two datasets, the grid-based bedrock elevation dataset (https://www.ngdc.noaa.gov/mgg/global/global.html, DOI: 10.7289/v5c8276m), and the glacier surface elevation obtained by a slope-dependent method, the individual glacier volumes in 1970s and 2000s are then calculated. In addition, the calculated results of individual glacier volumes in this study have been compared and verified with the existent results of several glacier volumes, relevant remote sensing datasets, and the global glacier thickness dataset based on the average of multiple glacier model outputs (https://www.research-collection.ethz.ch/handle/20.500.11850/315707, doi:10.3929/ethz-b-000315707), and the errors in the calculations have also been quantified. The established dataset in this study is expected to provide the data basis for the future regional water resources estimation and glacier ablation-involved researches. Moreover, the acquisition of the data also provides a new idea for the future glacier storage estimation.
0 2020-04-24
Contact Support
Northwest Institute of Eco-Environment and Resources, CAS
0931-4967287
poles@itpcas.ac.cn
Links
National Tibetan Plateau Data CenterFollow Us
A Big Earth Data Platform for Three Poles © 2018-2020 No.05000491 | All Rights Reserved
｜ 
No.11010502040845
Tech Support: westdc.cn
