TY  - Data
T1  - Desertification Sequence in semi-arid areas of northern China (2000-2019)
A1  - None
A1  - None
A1  - Liu Shulin
A1  - Liao Jie
DO  - 10.12072/ncdc.ZDYF.db1683.2022
PY  - 2022
DA  - 2022-04-18
PB  - National Cryosphere Desert Data Center
AB  - Based on the multi index desertification information extraction method with MODIS as the data source, taking mod09a1 and mod11a2 as the data sources, retrieve NDVI, MSAVI, albedo and FVC with mod09a1 products respectively, calculate LST with mod11a2 products, calculate TVDI with vegetation index and land surface temperature, and select the sample data of different types of desertification on the basis of artificial visual interpretation, By selecting the above six parameters, the dynamic characteristics of desertification in annual scale time series from 2000 to 2019 are obtained by machine learning and decision tree classification method.Because there are obvious spatial differences in the reference background of desertification land, and this data set does not further divide the whole study area, there is an obvious gap between the desertification land area given in this data set and the visual interpretation results, but it can be used for the analysis of desertification land change trend in the study area.The specific meanings of pixel values of grid data in each year are as follows:0 represents non desertification land1 represents slightly desertified land2 represents moderately desertified land3 represents heavily desertified land4 represents seriously desertified land.
DB  - NCDC
UR  - http://www.ncdc.ac.cn/portal/metadata/51e55bd9-d757-45cf-8df0-31457dc0fd52
ER  -