ERM

Earth Radiation Measurement

Satellites

FY-3 A to G

Status

Operational – Utilised in the period 2008 to ~ 2024

Mission

Earth radiation budget and Total solar irradiance

Instrument type

Two broad-band channels radiometer. Two units, one scanning, one non-scanning. In addition, 3 cavity radiometers for total solar irradiance

Scanning technique

Scanner: swath 2200 km; cross-track scanning,151 steps of 28 km s.s.p. every 4 s; non-scanning: 120 degrees viewing angle, 8 samples every 4 s. Total solar irradiance: sun-pointing

Coverage/cycle

Global coverage twice/day (total radiance) or once/day (short-wave)

Resolution (s.s.p.)

Scanner: 28 km - Non-scanner: N/A - Total solar irradiance: N/A

Resources

Mass: … kg - Power: … W - Data rate: … kbps

Channel

Spectral interval

Noise Equivalent Radiance

Absolute accuracy

SNR

Short-wave (outgoing)

0.2 - 3.8 µm

0.4 W m-2 sr-1

1.5 W m-2 sr-1

900

Total radiance (outgoing)

0.2 - 50 µm

0.4 W m-2 sr-1

1.1 W m-2 sr-1

1250

Total solar irradiance (incoming)

0.2 - 50 µm

0.2 W m-2

0.5 %

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