IRAS

Infra Red Atmospheric Sounder

Satellites

FY-3 A to G

Status

Operational – Utilised in the period 2008 to ~ 2024

Mission

Temperature/humidity sounding

Instrument type

26-channel IR radiometer (including 6 in short-wave)

Scanning technique

Cross-track: 56 steps of 26 km ssp, swath 2250 km - Along-track: one line each 42 km every 6.4 s

Coverage/cycle

Near-global coverage twice/day

Resolution (s.s.p.)

17 km IFOV

Resources

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

Wavelength

Wave number

Bandwidth

Radiometric accuracy (NEΔT or NEΔρ)

14.95 µm

669 cm-1

3 cm-1

2.50 K @ 290 K

14.71 µm

680 cm-1

10 cm-1

0.50 K @ 290 K

14.49 µm

690 cm-1

12 cm-1

0.37 K @ 290 K

14.22 µm

703 cm-1

16 cm-1

0.22 K @ 290 K

13.97 µm

716 cm-1

16 cm-1

0.20 K @ 290 K

13.64 µm

733 cm-1

16 cm-1

0.22 K @ 290 K

13.35 µm

749 cm-1

16 cm-1

0.18 K @ 290 K

12.47 µm

802 cm-1

30 cm-1

0.12 K @ 290 K

11.11 µm

900 cm-1

35 cm-1

0.10 K @ 290 K

9.71 µm

1030 cm-1

25 cm-1

0.14 K @ 290 K

7.43 µm

1345 cm-1

50 cm-1

0.27 K @ 290 K

7.33 µm

1365 cm-1

40 cm-1

0.37 K @ 290 K

6.52 µm

1533 cm-1

55 cm-1

0.53 K @ 290 K

4.57 µm

2188 cm-1

23 cm-1

0.10 K @ 290 K

4.52 µm

2210 cm-1

23 cm-1

0.05 K @ 290 K

4.47 µm

2235 cm-1

23 cm-1

0.08 K @ 290 K

4.45 µm

2245 cm-1

23 cm-1

0.08 K @ 290 K

4.19 µm

2388 cm-1

25 cm-1

0.06 K @ 290 K

3.98 µm

2515 cm-1

35 cm-1

0.10 K @ 290 K

3.76 µm

2660 cm-1

100 cm-1

0.11 K @ 290 K

1.64 µm

6098 cm-1

450 cm-1

0.1 %

1.24 µm

8065 cm-1

650 cm-1

0.1 %

0.94 µm

10638 cm-1

200 cm-1

0.1 %

0.94 µm

10638 cm-1

550 cm-1

0.1 %

0.885 µm

11299 cm-1

385 cm-1

0.1 %

0.69 µm

14500 cm-1

1000 cm-1

0.1 %