Aerosol optical property dataset of the Tibetan Plateau by ground-based observation (2009-2016)

The measurement data of the sun spectrophotometer can be directly used to perform inversion on the optical thickness of the non-water vapor channel, Rayleigh scattering, aerosol optical thickness, and moisture content of the atmospheric air column (using the measurement data at 936 nm of the water vapor channel). The aerosol optical property data set of the Tibetan Plateau by ground-based observations was obtained by adopting the Cimel 318 sun photometer, and both the Mt. Qomolangma and Namco stations were involved. The temporal coverage of the data is from 2009 to 2016, and the temporal resolution is one day. The sun photometer has eight observation channels from visible light to near infrared. The center wavelengths are 340, 380, 440, 500, 670, 870, 940 and 1120 nm. The field angle of the instrument is 1.2°, and the sun tracking accuracy is 0.1°. According to the direct solar radiation, the aerosol optical thickness of 6 bands can be obtained, and the estimated accuracy is 0.01 to 0.02. Finally, the AERONET unified inversion algorithm was used to obtain aerosol optical thickness, Angstrom index, particle size spectrum, single scattering albedo, phase function, birefringence index, asymmetry factor, etc.

0 2020-01-12

WATER: Dataset of airborne imaging spectrometer (OMIS-II) mission in the Linze station-Linze grassland flight zone on Jun. 6, 2008

The dataset of airborne imaging spectrometer (OMIS-II) mission was obtained in the Linze station-Linze grassland flight zone on Jun. 6, 2008. Data after radiometric correction and calibration and geometric approximate correction were released. The flying time of each route was as follows: {| ! id ! flight ! file ! starttime ! lat ! long ! alt ! image linage ! endtime ! lat ! long ! alt |- | 1 || 1-13 || 2008-06-06_09-32-22_DATA.BSQ || 09:56:32 || 39.167 || 100.044 || 2945.9 || 5718 || 10:02:53 || 39.362 || 100.191 || 2936.7 |- | 2 || 1-12 || 2008-06-06_10-02-38_DATA.BSQ || 10:08:42 || 39.373 || 100.193 || 2956.1 || 5565 || 10:14:53 || 39.182 || 100.049 || 2953.1 |- | 3 || 1-11 || 2008-06-06_10-14-39_DATA.BSQ || 10:19:51 || 39.177 || 100.039 || 2931.2 || 5432 || 10:25:54 || 39.363 || 100.179 || 2958.3 |- | 4 || 1-10 || 2008-06-06_10-25-39_DATA.BSQ || 10:31:50 || 39.376 || 100.182 || 2959.7 || 5396 || 10:37:50 || 39.190 || 100.041 || 2952.7 |- | 5 || 1-9 || 2008-06-06_10-37-35_DATA.BSQ || 10:43:06 || 39.179 || 100.026 || 2956.4 || 5399 || 10:49:06 || 39.368 || 100.169 || 2939.0 |- | 6 || 1-8 || 2008-06-06_10-48-51_DATA.BSQ || 10:55:20 || 39.383 || 100.174 || 2943.2 || 5643 || 11:01:36 || 39.1922 || 100.029 || 2944.8 |- | 7 || 1-7 || 2008-06-06_11-01-22_DATA.BSQ || 11:07:04 || 39.185 || 100.0175 || 2947.2 || 5306 || 11:12:58 || 39.373 || 100.159 || 2943.9 |- | 8 || 1-6 || 2008-06-06_11-12-43_DATA.BSQ || 11:18:57 || 39.386 || 100.162 || 2948.1 || 5604 || 11:25:10 || 39.196 || 100.018 || 2950.5 |- | 9 || 1-5 || 2008-06-06_11-24-56_DATA.BSQ || 11:30:22 || 39.188 || 100.006 || 2934.0 || 5469 || 11:36:26 || 39.378 || 100.149 || 2935.4 |- | 10 || 1-4 || 2008-06-06_11-36-12_DATA.BSQ || 11:42:30 || 39.389 || 100.151 || 2935.4 || 5570 || 11:48:41 || 39.198 || 100.007 || 2949.0 |- | 11 || 1-3 || 2008-06-06_11-48-27_DATA.BSQ || 11:54:21 || 39.205 || 100.005 || 2915.2 || 5028 || 11:59:57 || 39.380 || 100.138 || 2908.8 |- | 12 || 1-2 || 2008-06-06_11-59-42_DATA.BSQ || 12:06:00 || 39.395 || 100.142 || 2931.0 || 5523 || 12:12:08 || 39.205 || 99.999 || 2950.0 |- | 13 || 1-1 || 2008-06-06_12-11-53_DATA.BSQ || 12:18:17 || 39.197 || 99.985 || 2916.5 || 5451 || 12:24:20 || 39.389 || 100.131 || 2907.9 |}

0 2019-12-27

HiWATER: Multi-scale observation experiment on land surface temperature-dataset of component temperature in the down of Heihe River Basin (Thermal infrared radiometer) (2014-2016)

This dataset includes component temperatures measured by the thermal infrared (TIR) radiometers at the Mixed Forest and Sidaoqiao stations between 22 July, 2014 and 19 July, 2016. The Mixed Forest (101.1335 °E, 41.9903 °N, 874 m.a.s.l.) and Sidaoqiao (101.1374 °E, 42.0012 °N, 873 m.a.s.l.) stations were located in the downstream of the Heihe River basin, Dalaihubu Town, Ejin Banner, Inner Mongolia. At the Mixed Forest station, two TIR radiometers (SI-111, Apogee Instruments Inc., USA) connected to a data logger (CR800, Campbell Scientific Inc., USA) measured component temperatures of the sunlit canopy and shaded canopy. TIR radiometers were mounted horizontally at 5 m height on iron rods just south and north of a tree and pointed to its canopy. The distance from the sensor to the canopy was ~1 m. At the Sidaoqiao station, two SI-111 TIR radiometers connected to a CR800 data logger measured component temperatures of the soil and shrub. The first sensor pointed from 2 m height under a viewing zenith angle of 45° to bare soil; the second sensor was mounted at 1-m height and pointed horizontally into the shrub canopy.

0 2019-11-28

HiWATER: Dataset of ground truth measurements synchronizing with airborne PLMR mission in the Yingke oasis and Huazhaizi desert steppe on June 28-29, 2012

The first dataset of ground truth measurements synchronizing with airborne Polarimetric L-band Multibeam Radiometer (PLMR) mission was obtained in the Yingke oasis and Huazhaizi desert steppe on 28-29 June, 7, 10, 26 July, 2 August, 2012 (UTC+8). The dataset of ground truth measurements synchronizing with airborne Polarimetric L-band Multibeam Radiometer (PLMR) mission was obtained in the Linze Inland River Basin Comprehensive Research Station on 3 July, 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 in the southwest part of the Zhangye Oasis, which included two sampling plots. One was located in Gobi desert with an area of 1 km × 1 km. Due to its homogeneous landscape, around 10 points were sampled to acquire the situation of soil water content. The other sampling plot was designed in farmlands with a dominant plant type of maize. Ground measurements took place along 16 transects, which were arranged parallelly with an interval of 160 m between each other in the east-west direction. In each 2.4 km long transect, soil moisture was sampled at every 80 m in the north-south direction. Steven Hydro probes were used to collect soil moisture and other measurements. For each sampling point in farmland, 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). The field campaign started from 11:00 AM, but stopped at 4:00 PM on 28 June because of rain. The rest of measurements were completed from 10:30 AM to 5:30 PM on 29 June. Concurrently with soil moisture sampling, vegetation properties were measured at around 10 locations within the farmland 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, 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.

0 2019-09-15

HiWATER: Thermal-infrared hyperspectral radiometer (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), Linze region and Heihe riverway. The relative flight altitude is 2500 meters. The wavelength of TASI is 8-11.5 μm with a spatial resolution of 3 meters. Through the ground sample points and atmospheric data, the data are recorded in surface radiance processed by geometric correction and atmospheric correction.

0 2019-09-15

HiWATER: Dataset of airborne microwave radiometers (L bands) mission in the river way of the midstream of the Heihe River Basin on Jul. 4, 2012

The dataset of airborne Polarimetric L-band Multibeam Radiometers (PLMR) was acquired on 4 July, 2012, located along the riverway of Heihe River in the middle reaches of the Heihe River Basin. The aircraft took off at 10:50 am (UTC+8) from Zhangye airport and landed at 14:50 pm, with the flight time of 4 hours. The flight was performed in the altitude of about 1000 m and at the speed of about 220-250 km during the observation, corresponding to an expected ground resolution of about 300 m. The PLMR instrument flown on a small aircraft operates at 1.413 GHz (L-band), with both H- and V-polarizations at incidence angles of ±7.5°, ±21.5° and ±38.5°. PLMR ‘warm’ and ‘cold’ calibrations were performed before and after each flight. The processed PLMR data include 2 DAT files (v-pol and h-pol separately) and 1 KMZ file for each flying day. The DAT file contains all the TB values together with their corresponding beam ID, incidence angle, location, time stamp (in UTC) and other flight attitude information as per headings. The KMZ file shows the gridded 1-km TB values corrected to 38.5 degrees together with flight lines. Cautions should be taken when using these data, as the RFI contaminations are often higher than expected at v-polarization.

0 2019-09-15

WATER: Dataset of LAI measurements in the Linze station foci experimental area from May to Jul, 2008

The dataset of LAI measurements was obtained in the Linze station foci experimental area. (1) LAI of maize, desert scrub and the poplar measured by the fisheye camera (CANON EOS40D with a lens of EF15/28), shooting straight downwards, with exceptions of higher plants, which were shot upwards in Wulidun farmland quadrates (Jun. 3, 4 and 29, May 28 and 30 and Jul. 11), inside Linze station quadrates (Jun. 19, 25 and 30, Jul. 3 and 10, May 27), the desert transit zone (May 28 and 30) and the poplar forest (May 30). Sample points were archived in coordiantes.xls. Data included original photos (.JPG) and those processed by can_eye5.0 (in excel). For more details, see Readme file. (2) LAI measured by the ruler and the set square in Wulidun farmland quadrate inside Linze station on May 22, 23, 24, 28 and 30 and Jul. 11, 2008. Part of the samples were also measured by LI-3100 and compared with those by manual work for further correction. Data were archived as Excel files. (3) LAI and SD of maize measured by LAI2000 in Wulidun farmland quadrates (Jun. 24 and 29 and Jul. 10) and inside Linze station quadrates (Jun. 19, 25 and 30, Jul. 3, 9 and 10). Data educed from LAI2000 periodically were archived as text files (.txt) and marked with one ID. Raw data (table of word and txt) and processed data (Excel) were included. Besides, observation time, the observation method and the repetition were all archived. See the metadata record “WATER: Dataset of setting of the sampling plots and stripes in the Linze station foci experimental area” for more information of the quadrate locations.

0 2019-09-15

WATER: Dataset of spectral reflectance of canopy leafs observed by the integrating sphere in the Linze station foci experimental area from May to Jul, 2008

The dataset of spectral reflectance of canopy leafs observed by the integrating sphere was obtained by ASD Spectroradiometer (350~2 500 nm) and integrating spheres from BNU and the reference board (40% before Jun. 15 and 20% hereafter), in the Linze station foci experimental area. Maize quadrate, the desert green quadrate and withered scrub quadrate in Linze station (on May 28, 30, Jun. 19, 30 and Jul. 9), Wulidun farmland quadrates (on Jun. 24, 29 and Jul. 11) and the desert strips were measured. According to the fact that the ratio of the two DN values equals that of their reflectivity, the reflectivity and the tranmittivity can be calculated with the caliberation coefficient, reflection DN of the observed objects and reference plates. The reflectivity and the tranmittivity of interior vegetation leaves can be got by the integrating spheres. Raw spectral data were archived as binary files, which were recorded daily in detail, and pre-processed data on reflectance and transmittivity were archived as text files (.txt).

0 2019-09-15

HiWATER: Wide-angle Infrared Dual-mode line/area Array Scanner, WIDAS (26th, July, 2012)

On 26 July 2012, a Wide-angle Infrared Dual-mode line/area Array Scanner (WIDAS) carried by the Y-12 aircraft was used in a visible near Infrared thermal Dual-mode airborne remote sensing experiment, which is located in the artificial oasis eco-hydrology experimental area (5×5 km). WIDAS includes an CCD cameras with spatial resolution 0.2 m, a visible near Infrared multispectral camera with five bands scanner (an maximum observation angle 48° and spatial resolution 1 m), and a thermal image camera with spatial resolution 4.8 m. The CCD camera data are recorded in DN values processed by mosaic and orthorectification. The multispectral camera data are recorded in reflectance processed by atmospheric and geometric correction. Thermal image camera data are recorded in radiation brightness temperature processed by atmospheric and geometric correction.

0 2019-09-15