TY  - Data
T1  - Brightness and temperature data set of passive microwave SMMR in China
A1  - Chetao
A1  - Jin rui
DO  - 10.12072/ncdc.westdc.db3699.2023
PY  - 2020
DA  - 2020-03-26
PB  - National Cryosphere Desert Data Center
AB  - China's SMMR data set mainly uses the microwave brightness temperature (TB) data obtained by scanning multichannel microwave radiometer (SMMR) carried by nimbus-7 satellite. It includes the brightness temperature of 06h, 06v, 10h, 10V, 18h, 18V, 21h, 21V, 37h and 37V channels from 1978 to 1987. H represents horizontal polarization and V represents vertical polarization. The nimbus-7 solar synchronous polar orbit satellite, launched in October 1978, is a dual polarization microwave radiometer with five frequencies and ten channels for measuring surface radiation, which is equipped with a microwave sensor SMMR. It scans the earth's surface at a fixed angle of incidence of about 50.3 ° with a width of 780km and passes through the equator at 12:00 noon (ascending orbit) and 24:00 midnight (descending orbit). The time resolution of SMMR is daily, but the same surface is revisited every 5-6 days. The characteristic values are shown in the table below. Some eigenvalues of SMMRChannel frequency (GHz) spatial resolution (km) temperature resolution (k) antenna wave velocity width (DEG)37V/H   37.00   30  1.5 0.821V/H   21.00   60  1.5 1.418V/H   18.00   60  1.2 1.610V/H   10.69   97.5    0.9 2.66V/H    6.60    156 0.9 4.21. File format and naming:Each group of data consists of remote sensing data file,. JPG image file,. Met auxiliary information file,. Tim time information file and corresponding. Met auxiliary time information file. The file names and naming rules of each group of data under SMMR grid China directory are as follows:China-ease-n07-ml / haaaabbba / d.cch/v (remote sensing data) china-ease-n07-ml / haaaabbba / d.cch/v.jpg (image file)China-ease-n07-ml / haaaabbba / d.cch/v.met (auxiliary information file)China-ease-n07-ml / haaaabbba / d.tim (time information file) china-ease-n07-ml / haaaabbba / d.tim.met (time information auxiliary file). 2. Coordinate system and projection:The projection mode is equal product cutting cylinder projection, and the double standa
DB  - NCDC
UR  - http://www.ncdc.ac.cn/portal/metadata/6c62a54a-462f-4f1c-a1c6-e48619f166a5
ER  -