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Snow cover dataset is produced by snow and cloud identification method based on optical instrument observation data, covering the time from 1989 to 2018 (two periods, from January to April and from October to December) and the region of Qinghai-Tibet Plateau (17°N-41°N, 65°E-106°E) with daily product, which takes equal latitude and longitude projection with 0.01°×0.01° spatial resolution, and characterizes whether the ground under clear sky or transparent thin cloud is covered by snow. The input data sources include AVHRR L1 data of NOAA and MetOp serials of satellites, and L1 data corresponding to AVHRR channels taken from TERRA/MODIS. Decision Tree algorithm (DT) with dynamic thresholds is employed independent of cloud mask and its cloud detection emphasizes on reserving snow, particularly under transparency cirrus. It considers a variety of methods for different situations, such as ice-cloud over the water-cloud, snow in forest and sand, thin snow or melting snow, etc. Besides those, setting dynamic threshold based on land-surface type, DEM and season variation, deleting false snow in low latitude forest covered by heavy aerosol or soot, referring to maximum monthly snowlines and minimum snow surface brightness temperature, and optimizing discrimination program, these techniques all contribute to DT. DT discriminates most snow and cloud under normal circumstances, but underestimates snow on the Qinghai-Tibet Plateau in October. Daily product achieves about 95% average coincidence rate of snow and non-snow identification compared to ground-based snow depth observation in years. The dataset is stored in the standard HDF4 files each having two SDSs of snow cover and quality code with the dimensions of 4100-column and 2400-line. Complete attribute descriptions is written in them.

Data file naming and use method

The data file is named by five fields: space based optical instrument and snow cover product code, satellite name, product time, coverage area, version number, etc., with“hdf”data format suffix, such as the form of AVH10A1_SATENM_ yyyymmdd_QTP_V01.hdf, where AVH10A1 indicates daily snow cover product generated based on AVHRR or corresponding instrument channel observation data, SATENM is the satellite name (values are NOAA11, NOAA14, NOAA16, NOAA17, EOSMLT and MetOpA), yyyymmdd indicates the date, QTP indicates the Qinghai-Tibet Plateau, and V01 indicates the version number. The data is stored in the standard HDF4 format and can be viewed by ENVI, ARCGIS, HDFView, Hdfexp and other software. Users can also write programs to process and use it.

Required Data Citation View Data Cite Help About Data Citation

ZHENG Zhaojun, CHU Duo. Snow cover dataset based on optical instrument remote sensing with 1km spatial resolution on the Qinghai-Tibet Plateau (1989-2018). National Tibetan Plateau Data Center, 2019. doi: 10.11888/Snow.tpdc.270465. (Download the reference： RIS | Bibtex )

Using this data, the data citation is required to be referenced and the related literatures are suggested to be cited.

Support Program

Construction of Snow Remote Sensing Dataset for Climate in the Qinghai-Tibet Plateau (No:GYHY201206040)

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To respect the intellectual property rights, protect the rights of data authors,expand servglacials of the data center, and evaluate the application potential of data, data users should clearly indicate the source of the data and the author of the data in the research results generated by using the data (including published papers, articles, data products, and unpublished research reports, data products and other results). For re-posting (second or multiple releases) data, the author must also indicate the source of the original data.

Example of acknowledgement statement is included below: The data set is provided by National Tibetan Plateau Data Center (http://data.tpdc.ac.cn).

License： This work is licensed under an Attribution 4.0 International (CC BY 4.0)

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