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HiWATER: Land surface temperature product in the middle reaches of the Heihe River Basin (30th, June, 2012)

On 30 June 2012 (UTC+8), TASI sensor carried by the Harbin Y-12 aircraft was used in a visible near Infrared hyperspectral airborne remote sensing experiment, which is located in the observation experimental area (30×30 km). The relative flight altitude is 2500 meters. Land surface temperature product was obtained at a resolution of 3 m using a modified temperature/emissivity separation algorithm based on TASI surface radiance data. The product were validated with in situ ground measurements. The validation results indicated that the Land surface temperature product agreed with the ground LSTs well with RMSE lower than 1.5 K.

2019-09-14

HiWATER: Dataset of ground truth measurements synchronizing with airborne PLMR mission in the upper reaches of the Heihe River Basin on August 1, 2012

The dataset of ground truth measurements synchronizing with airborne Polarimetric L-band Multibeam Radiometer (PLMR) mission was obtained in upper reaches of the Heihe River Basin on 1 August, 2012. PLMR is a dual-polarization (H/V) airborne microwave radiometer with a frequency of 1.413 GHz, which can provide multi-angular observations with 6 beams at ±7º, ±21.5º and ±38.5º. The PLMR spatial resolution (beam spot size) is approximately 0.3 times the altitude, and the swath width is about twice the altitude. The measurements were conducted along two transects respectively located at the west and east branches of the Babaohe River and two sampling plots in the A’rou foci experimental area. Along the transects, soil moisture was sampled at every 50 m in the west-east direction. In order to keep the ground measurements following the airborne mission as synchronous as possible in temporal, measurements were made discontinuously. In the A’rou foci experimental area, two sampling plots were identified with areas of 1.5 km × 0.6 km and 0.85 km × 0.6 km. In each plot, soil moisture was sampled at every 50 m in the west-east direction and 100 m in the north-south direction. Steven Hydro probes were used to collect soil moisture and other measurements. Concurrently with soil moisture sampling, vegetation properties were measured at some typical sampling plots. Observation items included: Soil parameters: volumetric soil moisture (inherently converted from measured soil dielectric constant), soil temperature, soil dielectric constant, soil electric conductivity. Vegetation parameters: biomass, vegetation water content, canopy height. Data and data format: This dataset includes two parts of measurements, i.e. soil and vegetation parameters. The former is as shapefile, with measured items stored in its attribute table. The measured vegetation parameters are recorded in an Excel file.

2019-09-14

HiWATER: Dataset of surface temperature and albedo on village roof in the middle reaches of the Heihe River Basin

A land surface temperature and upward/downward shortwave radiation observation system was set up on the roof, which locate on the edge of No.4 eddy covariance system (EC4) of the MUlti-Scale Observation EXperiment on Evapotranspiration over heterogeneous land surfaces 2012 (MUSOEXE-12). This observation site can offer in situ calibration data for TASI, WiDAS and L band sensor used in aerospace experiment. Observation Site: This point is located in a large and homogeneous adobe roof in Shiqiao Village, Xiaoman Town, Zhangye City. Land surface of observation site is relatively flat and uniform, and also not tall trees around. It’s about 20 meters away from southwest No.4 eddy covariance system (EC4) observation points. The coordinates of this site: 38°52′38.50″ N,100°21′27.00″ E。 Observation Instrument: Observation system is composed of a SI-111 infrared radiometer (Campbell, USA) installed vertically downward, two CMP3 pyranometer (Kipp&Zonen, Netherlands) one upward, another downward. Observation height is 1.0 m, data logging by a Campbell CR850 logger. Sensor orientation: Observation mounting arm has 3 m long, parallel to roof edge, azimuth angle: 156° (East by south 66°) Observation Time: This site operates from 23 June, 2012 to 20 September, 2012. Observation data laagered by every 5 seconds uninterrupted. Output data contained sample data of every 5 seconds and mean data of 1 minute. Accessory data: Land surface (adobe roof) temperature, downward/upward total solar radiation, surface albedo. Dataset is stored in *.dat file, which can be read by Microsoft excel or other text processing software (UltraEdit, et. al). Table heads meaning: Rs_downwell, downward shortwave radiation (W/m^2); Rs_upwell, upward (reflect) shortwave radiation (W/m^2); albedo, calculate by Rs_upwell/ Rs_downwell. SBT_C, body temperature of SI-111 sensor (℃); Target_C, Target of surface temperature (℃). Dataset is stored day by day, named as: data format + site name + interval time + date + time. The detailed information about data item showed in data header introduction in dataset.

2019-09-14

HiWATER: Dataset of leaf area index by LAI2200 in the lower reaches of the Heihe River Basin

LAI observation was carried out for the typical underlying surface in the lower reaches of Heihe River Basin during the aviation flight experiment in 2014. The observation started on 24 July, 2014 and finished on 1 August, 2014. 1. Observation time On days of 24 July, 27 July, 30 July, 31 July and 1 August, 2014 2. Samples and observation methods Large areas with homogeneous vegetation (greater than 100 m * 100 m) were chosen as the observation samples. And forty field samples were selected according to the characteristics of vegetation distribution in the downstream. The land-use types including the cantaloupe, the Tamarix chinensis, the reeds, the weeds, the Karelinia caspica, the Sophora alopecuroides and so on. LAI data were calculated according to the transmittance derived from an A value (above-canopy readings) and four B values (below readings). More than two LAI values were obtained for each sample. At the same time, the heights of the vegetation in each sample were measured. 3. Observation instrument LAI 2200 4. Data storage The observation recorded data were stored in excel and the original LAI data were stored in txt files.

2019-09-13

HiWATER: Dataset of the Portable Soil Respiration in the middle reaches of the Heihe River Basin (2012)

During the 2012 aerial remote sensing experiment conducted midstream, Li-Cor8100 was used to measure soil respiration every five days in the EC matrix area. Instrument: LI-Cor8100 Measuring Method: Soil respiration ring was made using PVC pipe with length of 10 cm. Before measuring soil respiration, soil respiration ring was inserted into the soil, 4 cm in soil and 6 cm above soil. Soil respiration measurement should be taken after standing for at least 24 hours science ring was inserted in soil. Sample measurement time is during 9-12 in the morning. Set of three replicates per plot. Marked according to EC site name. Data content: Data content includes header information, and once every five days repeated three times observations value and the average value. Measuring location: EC sites within the matrix core experiment area (No. EC01 to EC17), each plot set three repeat samples. For the superstation (EC15) plot set nine repeat samples. Measuring time: From 6 June to 20 August, 2012, once every five days for site EC01, EC03, EC05, EC10, EC11, EC12, EC13, EC14, and EC17; from 1 July to 20 August, 2012, once every five days for site EC02, EC04, EC06, EC07, EC08, EC09 and EC16. The time used in this dataset is in UTC+8 Time. Part of the observation points during the observation just irrigation, these times are not observable.

2019-09-13

HiWATER: Dataset of vegetation LAI measured by LAI2000 in the middle reaches of the Heihe River Basin

This dataset is the LAI observation in the artificial oasis experimental region of the middle stream of the Heihe River Basin. The observation period is from 24 May to 20 September 2012 (UTC+8). Measurement instruments: LAI-2000 (Beijing Normal University) Measurement positions: Core Experimental Area of Flux Observation Matrix 18 corn samples, 1 orchard sample, 1 artificial white poplar sample Measurement methods: To measure the incoming sky radiation on the canopy firstly. Then the transmission sky radiation are mearued under the canopy for serveral times. The canopy LAI is retrieved by using the gap probability model.

2019-09-13

HiWATER: Dataset of ground truth measurements synchronizing with TerraSAR-X satellite overpassing in the Daman Superstation on June 4, 2012

The first dataset of ground truth measurements synchronizing with TerraSAR-X was obtained in the Daman foci experimental area on 4 June, 2012. The satellite image was in StripMap mode and HH/VV polarization with an incidence angle of 22-24°, and the overpass time was approximately at 19:00 UTC+8. The second dataset of ground truth measurements synchronizing with TerraSAR-X was obtained in the Daman foci experimental area on 15 June, 2012. The satellite image was in StripMap mode and HH/VV polarization with an incidence angle of 22-24°, and the overpass time was approximately at 19:00 UTC+8. The third dataset of ground truth measurements synchronizing with TerraSAR-X was obtained in the Daman foci experimental area on 26 June, 2012. The satellite image was in StripMap mode and HH/VV polarization with an incidence angle of 22-24°, and the overpass time was approximately at 19:00 UTC+8. The measurements were conducted at a sampling plot southeast to the Daman Superstation with an area of around 100 m × 100 m, which was dominantly planted with maize. Steven Hydro probes were used to collect soil moisture and other measurements with an interval of 5 m. For each sampling point, two measurements were acquired within an area of 1 m2, with one for the soil covered by plastic film (point name was tagged as LXPXXA) and the other for exposed soil (point name was tagged as LXPXXB). Concurrently with soil moisture sampling, vegetation properties were measured at around 10 locations within this sampling plot. Observation items included: Soil parameters: volumetric soil moisture (inherently converted from measured soil dielectric constant), soil temperature, soil dielectric constant, soil electric conductivity. Vegetation parameters: biomass, LAI, vegetation water content, canopy height, row distance and leaf chlorophyll content. Data and data format: This dataset includes two parts of measurements, i.e. soil and vegetation parameters. The former is as shapefile, with measured items stored in its attribute table. The measured vegetation parameters are recorded in an Excel file.

2019-09-13

HiWATER: Land surface temperature product in the middle reaches of the Heihe River Basin (10th, July, 2012)

On 10 July 2012 (UTC+8), TASI sensor carried by the Harbin Y-12 aircraft was used in a visible near Infrared hyperspectral airborne remote sensing experiment, which is located in the observation experimental area (30×30 km). The relative flight altitude is 2500 meters. Land surface temperature product was obtained at a resolution of 3 m using a modified temperature/emissivity separation algorithm based on TASI surface radiance data. The product were validated with in situ ground measurements. The validation results indicated that the Land surface temperature product agreed with the ground LSTs well with RMSE lower than 1.5 K.

2019-09-13

HiWATER: the albedo in the middle reaches of the Heihe River Basin (Jun. 29, 2012)

The albedo product was obtained based on the visible and near-infrared hyperspectral radiometer (29 June, 2012) which covered the artificial oasis eco-hydrology experimental area (5.5 km*5.5 km)with a 5 m spatial resolution.

2019-09-13

HiWATER: CCD reference image in core experimental area of flux observation matrix in the midstream of the Heihe River Basin

This dataset includes two reference images. The first one is before the calibration and validation experiment and the second one is during the calibration and validation experiment. The first image was shoot and mosaicked by CCD camera on 8 November, 2011. It was mainly used to design the experiment in the middle stream. The spatial resolution is 0.3 m for raw image and 0.5 m for the mosaicked image. The second reference image is CASI image shoot on 29 June, 2012. This image is mainly used to crop structure mapping in the experiment area. The spatial resolution is 0.3 m for raw image and 0.5 m for the mosaicked image. Data format:GeoTIFF Projection:The 2000 national geodetic coordinate system

2019-09-12