Visible and Infra Red Radiometer (VIRR)


This instrument is a copy of the Multi-channel Visible and Infrared Scanning Radiometer (MVISR, 10 channels) that used to fly on FY-1C/D satellites (1999-2011). For the sake of observational continuity, the 10-channel radiometer VIRR onboard FY-3A/B/C remains the same as the MVISR on FY-1C/D. However, it is planned that FY-3D or future FY-3s will not carry VIRR. The VIRR’ work will be taken over by MERSI-2 instrument to be flying on FY-3D and future FY-3s.

Visible-infrared light Scanning Radiometer has ten 1km-resolution spectral channels, including the high sensitivity visible channel. And there are three infrared atmospheric window channels. The primary purpose of Visible-infrared light Scanning Radiometer is to monitor global cloud cover, identification of cloud height, type and phase, aimed at detecting sea surface temperature, monitoring of vegetation growth conditions and types of monitoring and identification of high-temperature of the snow-covered surface at detecting Ocean color, etc.

Satellite FY-3A FY-3B FY-3C 
No. Channels 10
Spatial Resolution 1.1km
Weight 55kg
Power 45W


Central wavelength (μm) Band range (μm) Noise equivalent reflectivity ρ(%) / Noise equivalent temperature difference (300K) Dynamic range (ρ/k)
0.455 0.43~0.48 0.05% 0~50%
0.505 0.48~0.53 0.05% 0~50%
0.555 0.53~0.58 0.05% 0~50%
0.630 0.58~0.68 0.1% 0~100%
0.865 0.84~0.89 0.1% 0~100%
1.360 1.325~1.395 0.19% 0~90%
1.600 1.55~1.64 0.15% 0~90%
3.740 3.55~3.93 0.3K (FY-3A 0.4K) 180~350K
10.80 10.3~11.3 0.2K 180~330K
12.00 11.5~12.5 0.2K 180~330K

Data and Products

Satellite Instrument Datasets
FY-3C VIRR L1 dataL2L3 product
FY-3B VIRR L1 dataL2L3 product
FY-3A VIRR L1 dataL2L3 product

Calibration and Validation

VIRR calibration and validation