HIRS 3/4

High-resolution Infra Red Sounder 3 / 4

Satellites

TIROS-N, NOAA 6 to 17, NOAA 18 and 19 (HIRS/4) - MetOp 1 and 2 (HIRS/4)

Status

Operational – Utilisation period: 1978 to ~ 2014 on NOAA, 2006 to ~ 2016 on MetOp

Mission

Temperature/humidity sounding

Instrument type

20-channel IR radiometer (including one VIS)

Scanning technique

Cross-track: 56 steps of 26 km s.s.p., swath 2200 km - Along-track: one line each 42 km every 6.4 s

Coverage/cycle

Near-global coverage twice/day

Resolution (s.s.p.)

18 km for HIRS/3, 10 km IFOV for HIRS/4

Resources

Mass: 35 kg - Power: 24 W - Data rate: 2.88 kbps

Wavelength

Wave number

Bandwidth

Radiometric accuracy (NEΔN or SNR)

14.95 µm

669 cm-1

3 cm-1

3.00 mW m-2 sr-1 cm

14.71 µm

680 cm-1

10 cm-1

0.67 mW m-2 sr-1 cm

14.49 µm

690 cm-1

12 cm-1

0.50 mW m-2 sr-1 cm

14.22 µm

703 cm-1

16 cm-1

0.31 mW m-2 sr-1 cm

13.97 µm

716 cm-1

16 cm-1

0.21 mW m-2 sr-1 cm

13.64 µm

733 cm-1

16 cm-1

0.24 mW m-2 sr-1 cm

13.35 µm

749 cm-1

16 cm-1

0.20 mW m-2 sr-1 cm

12.47 µm

802 cm-1

16 cm-1

0.15 mW m-2 sr-1 cm

11.11 µm

900 cm-1

35 cm-1

0.10 mW m-2 sr-1 cm

9.71 µm

1030 cm-1

25 cm-1

0.15 mW m-2 sr-1 cm

7.33 µm

1364 cm-1

40 cm-1

0.20 mW m-2 sr-1 cm

6.52 µm

1534 cm-1

55 cm-1

0.20 mW m-2 sr-1 cm

4.57 µm

2188 cm-1

23 cm-1

0.006 mW m-2 sr-1 cm

4.52 µm

2210 cm-1

23 cm-1

0.003 mW m-2 sr-1 cm

4.47 µm

2237 cm-1

23 cm-1

0.004 mW m-2 sr-1 cm

4.45 µm

2247 cm-1

23 cm-1

0.004 mW m-2 sr-1 cm

4.13 µm

2420 cm-1

28 cm-1

0.002 mW m-2 sr-1 cm

4.00 µm

2500 cm-1

35 cm-1

0.002 mW m-2 sr-1 cm

3.76 µm

2660 cm-1

100 cm-1

0.001 mW m-2 sr-1 cm

0.69 µm

N/A

0.05 µm

0.10 % albedo