BackForwardInstrument:  IASI-NG 

Instrument details
Acronym IASI-NG
Full name Infrared Atmospheric Sounder Interferometer - New Generation
Purpose Temperature/humidity sounding, ozone profile and total-column or profiles of green-house gases (C2H2, C2H4, C2H6, CFC-11, CFC-12, CH3OH, CH4, CO, H2CO2, HCN, HNO2, HNO3, N2O, NH3, PAN, SO2)
Short description 16,921 channels, range 645-2760 cm-1 (3.62-15.50 μm) split in 12 bands [see detailed characteristics below]. Spectral resolution 0.125 cm-1 (unapodised)
Background Evolution of IASI on Metop A, Metop-B, Metop-C
Scanning Technique Cross-track: 14 Earth views (seven earth views or Field of Regards (FOR) are placed symmetrically on either side of nadir), one cold space view, one blackbody view, duration 15.6s, 2000 km swath width. Along-track: The instrument scans left to right according to in-flight direction (Sunward).
Resolution Each FOR contains 4×4 fields of view (FOV), which implies 14 X 16 FOVS per scan line. Each FOV has a 12 km ground resolution; spectral resolution 0.25 cm-1, spectral sampling 0.125 cm-1
Coverage / Cycle Near-global coverage twice/day
Mass 360 kg Power 500 W Data Rate 6 Mbps

 

Providing Agency CNES
Instrument Maturity Backed by strong heritage
Utilization Period: ≥2023 to ≥2044
Last update: 2020-02-18
Detailed characteristics

Band

Wavelength

Wavenumber

NEΔT after apodisation

IAS-1

15.50 μm

15.27 μm

15.08 μm

14.49 μm

645 cm-1

655 cm-1

663 cm-1

690 cm-1

0.39 K @ 280 K

0.26 K @ 280 K

0.225 K @ 280 K

0.225 K @ 280 K

IAS-2

12.99-14.49 μm

690-770 cm-1

0.130 K @ 280 K

IAS-3

10.00-12.99 μm

770-1000 cm-1

0.130 K @ 280 K

IAS-4

9.35-10.00 μm

1000-1070 cm-1

0.195 K @ 280 K

IAS-5

8.70-10.00 μm

1070-1150 cm-1

0.195 K @ 280 K

IAS-6

6.06-8.70 μm

1150-1650 cm-1

0.130 K @ 280 K

IAS-7

4.76-6.06 μm

1650-2100 cm-1

0.449 K @ 280 K

IAS-8

4.59-4.76 μm

2100-2180 cm-1

0.156 K @ 280 K

IAS-9

4.44-4.59 μm

2180-2250 cm-1

0.26 K @ 280 K

IAS-10

4.13-4.44 μm

2250-2420 cm-1

0.26 K @ 280 K

IAS-11

4.13 μm

4.08 μm

3.85 μm

3.70 μm

2420 cm-1

2450 cm-1

2600 cm-1

2700 cm-1

0.26 K @ 280 K

0.26 K @ 280 K

0.65 K @ 280 K

1.138 K @ 280 K

IAS-12

3.70 μm

3.62 μm

2700 cm-1

2760 cm-1

1.138 K @ 280 K

1.43 K @ 280 K

Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Instrument classification
  • Earth observation instrument
  • Passive optical radiometer or spectrometer
  • Cross-nadir infrared sounder, possibly including VIS channels
Mission objectives
Primary mission objectives
  • Atmospheric temperature
  • Height of the top of PBL
  • Height of the tropopause
  • Integrated Water Vapour (IWV)
  • O3 Total Column
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Tentative Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers
VariableRelevance for measuring this variableOperational limitationsExplanation
Atmospheric temperature1 - primaryCloud sensitive.MWIR and TIR spectrometry in the CO2 4.3 and 15 micrometer bands
C2H2 Mole Fraction1 - primaryCloud sensitive.TIR spectrometry. C2H2 lines around 7.5 and 13.7 micrometers
C2H6 Mole Fraction2 - very highCloud sensitive.TIR spectrometry. C2H6 lines around 12 micrometers
CFC-11 Mole Fraction1 - primaryCloud sensitive.. Coarse vertical resolution.TIR spectrometry. CFC-11 lines around 9.2 and 11.7 micrometers
CFC-12 Mole Fraction1 - primaryCloud sensitive.TIR spectrometry. CFC-12 lines around 8.8 and 10.8 micrometers
HCFC-22 Mole Fraction1 - primaryCloud sensitive.TIR spectrometry. HCFC-22 lines around 7.6, 9.0 and 12.3 micrometers
HC3Br Mole Fraction1 - primaryCloud sensitive.Spectrometry in the HC3Br bands around 6.7, 7.9 and 10.5 micrometers
CH4 Mole Fraction2 - very highCloud sensitive.MWIR and TIR spectrometry. CH4 lines around 3.4, 4.3 and 7.7 micrometers
ClONO2 Mole Fraction1 - primaryCloud sensitive.MWIR and TIR spectrometry. ClONO2 lines around 5.7, 7.7 and 12.5 micrometers
Cloud cover3 - highDiscontinuous coverage.MWIR and TIR spectrometry
Cloud top height2 - very highDiscontinuous coverage.MWIR and TIR spectrometry in window and water vapour band (for emissivity) to estimate cloud top height from its temperature
Cloud top temperature1 - primaryDiscontinuous coverage.TIR spectrometry in window and water vapour band (for emissivity)
Cloud type4 - fairDiscontinuous coverage.MWIR and TIR spectrometry
CO Mole Fraction3 - highCloud sensitive.MWIR spectrometry. CO lines around 4.6 micrometers
CO2 Mole Fraction2 - very highCloud sensitive.MWIR and TIR spectrometry. CO2 lines around 4.3 and 15 micrometers
COS Mole Fraction1 - primaryCloud sensitive.MWIR and TIR spectrometry. COS lines around 4.8 and 11.6 micrometers
Downward long-wave irradiance at Earth surface1 - primaryCloud sensitive.. Highly indirect.MWIR and TIR spectrometry including water vapour and CO2 bands
H2O Mole Fraction1 - primaryCloud sensitive.MWIR/TIR spectrometry in a range centred on 6.3 micrometers
Height of the top of PBL3 - highCloud sensitive.MWIR and TIR spectrometry. Height of PBL top from temperature profile
Height of the tropopause3 - highCloud sensitive.TIR spectrometry. Height of tropopause from temperature profile
HNO3 Mole Fraction1 - primaryCloud sensitive.. Coarse vertical resolution.MWIR and TIR spectrometry. HNO3 lines around 5.9, 7.6 and 11.3 micrometers
Land surface temperature2 - very highCloud sensitive.. Coarse spatial resolution.MWIR and TIR spectrometry (inclusive of several narrow-bandwidth windows and absorption bands for atmospheric corrections)
Long-wave Earth surface emissivity1 - primaryCloud sensitive.. Long time series needed.MWIR and TIR spectrometry measuring land temperature in many windows. Emissivity inferred by statistical analysis
N2O Mole Fraction2 - very highCloud sensitive.MWIR and TIR spectrometry. N2O lines around 4.5 and 7.7 micrometers
1 - primaryCloud sensitive.MWIR and TIR spectrometry. N2O5 lines around 5.8 and 8 micrometers
NO Mole Fraction1 - primaryCloud sensitive.MWIR spectrometry. NO lines around 5.3 micrometers
NO2 Mole Fraction3 - highCloud sensitive.TIR spectrometry. NO2 lines around 6.1 micrometers
NO2 Total Column1 - primaryCloud sensitive.TIR spectrometry. NO2 lines around 6.1 micrometers
O3 Mole Fraction3 - highCloud sensitive.TIR spectrometry. Ozone band around 9.7 micrometers
O3 Total Column3 - highCloud sensitive.TIR channel(s). Ozone lines in band around 9.7 micrometers
PAN Mole Fraction1 - primaryCloud sensitive.MWIR and TIR spectrometry. PAN lines around 5.7, 8.6 and 12.5 micrometers
PSC occurrence2 - very highCoarse vertical resolution.MWIR and TIR spectroscopy
Sea surface temperature1 - primaryCloud sensitive.MWIR and TIR spectrometry (inclusive of several narrow-bandwidth windows and absorption bands for atmospheric corrections)
SF6 Mole Fraction1 - primaryCloud sensitive.TIR spectrometry. SF6 lines around 10.5 micrometers
SO2 Mole Fraction1 - primaryCloud sensitive.TIR spectrometry. SO2 lines around 7.3 and 8.6 micrometers
SO2 Total Column1 - primaryCloud sensitive.TIR spectrometry. SO2 lines around 7.3 and 8.6 micrometers
Specific humidity1 - primaryCloud sensitive.TIR spectrometry in the water vapour band around 6.3 micrometers
Integrated Water Vapour (IWV)2 - very highCloud sensitive.TIR spectrometry in the bands around 6.3 and above 11 micrometers
Temperature of the tropopause2 - very highCloud sensitive.TIR spectrometry. Tropopause temperature from temperature profile
Upward spectral radiance at TOA2 - very highMissing all Short-waves.MWIR and TIR spectrometry resolving water vapour lines in the bands around 6.3 micrometers and 11 to 15 micrometers; and other greenhouse gases
Upward long-wave irradiance at TOA3 - highSpectral interpolation needed.MWIR and TIR spectrometry in the windows regions around 3.7 and 11 micrometers, and in water vapour and CO2 bands around 4,3, 6.3 and 15 micrometers
Upward long-wave irradiance at Earth surface1 - primaryCloud sensitive.. Highly indirect.MWIR and TIR channels in windows around 3.7 and 11 micrometers, and in water vapour and CO2 bands around 4,3, 6.3 and 15 micrometers
Wind (horizontal)3 - highCloud sensitive.. Limited to high latitudes.TIR spectrometry in the 6.3 micrometers band. Wind profile in clear air by tracking water vapour patches in the humidity profile