2. COST 723 Training School - Cargese 4 - 14 October 2005 OBS 3 Radiative transfer for thermal radiation. Instruments Bruno Carli

3. COST 723 Training School - Cargese 4 - 14 October 2005 Table of Contents Space instruments Recent and future instruments (IMG, ILAS, AIRS, MIPAS, TES, HIRDLS, ACE, IASI, CrIS, GIFTS, GGOS, REFIR) General considerations

4. COST 723 Training School - Cargese 4 - 14 October 2005 Space Instruments

5. COST 723 Training School - Cargese 4 - 14 October 2005 IMG: Interferometric Monitor for Greenhouse Gases Agency: NASDA Satellite: ADEOS I Launched on 17 th August 1996. Stopped on 30th June 1997. IMG overview

6. COST 723 Training School - Cargese 4 - 14 October 2005 IMG IMG is a nadir-looking Fourier transform infrared spectrometer (FTIR) operating in the spectral range from 3300 - 714 cm -1 (3.3 - 14.7 µm), with a spectral resolution of 0.1 cm -1 (apodized). IFOV=10 mrad (8x8 km 2 footprint)

7. COST 723 Training School - Cargese 4 - 14 October 2005 ILAS I and II overview ILAS I and II: Improved Limb Atmospheric Spectrometer Agency: NASDA / JAXA Satellites: ADEOS I and II ADEOS-I launched on 17 th August 1996. Stopped on 30 th June 1997. ADEOS-II launched on 10 th April 2003. Stopped on 24 th October 2003.

8. COST 723 Training School - Cargese 4 - 14 October 2005 ILAS I e II ILAS is a solar occultation grating spectrometer with two gratings, one measuring in the thermal IR with 44 channels in the range from 6.21- 11.77 µm (850-1610 cm-1), the other measuring in the VIS and IR with 1024 channels in the range of 0.753 - 0.784 µm. IFOV (at tangent height) 2 km (vertical) x 13 km (horizontal).

9. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS: Michelson Interferomer for Passive Atmospheric Sounding Agency: ESA Satellite: Envisat Launched on 1 st march 2002. Operating. MIPAS overview

10. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS is a Fourier Transform (FT) Spectrometer that measures the middle infrared (MIR) emission of the atmosphere at the limb. MIPAS

11. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS FT MIPAS is a Fourier Transform (FT) Spectrometer that measures the middle infrared (MIR) emission of the atmosphere at the limb.

12. COST 723 Training School - Cargese 4 - 14 October 2005 Spectral range: 685 - 2410 cm -1, = 14.6 – 4.15  m Spectral resolution 0,025 cm -1 unapodized Spectral resolution FWHM  0.035 cm -1 Vibrational spectra of molecules MIPAS MIPAS is a Fourier Transform (FT) Spectrometer that measures the middle infrared (MIR) emission of the atmosphere at the limb.

13. COST 723 Training School - Cargese 4 - 14 October 2005 Spontaneous thermal emission (blackbody) of the atmosphere Continuous (day and night) measurements are possible MIPAS MIPAS is a Fourier Transform (FT) Spectrometer that measures the middle infrared (MIR) emission of the atmosphere at the limb.

14. COST 723 Training School - Cargese 4 - 14 October 2005 In a limb view the line of sight (LOS) penetrate the atmosphere down to a minimum altitude (tangent altitude) and exits again to space. A typical limb sequence is made of a set of measurements made with different tangent altitudes (typically 3 km increments). MIPAS MIPAS is a Fourier Transform (FT) Spectrometer that measures the middle infrared (MIR) emission of the atmosphere at the limb.

15. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS Functional Description

16. COST 723 Training School - Cargese 4 - 14 October 2005 Front End Optics (FEO) Azimuth Scan Unit Telescope Baseplate Elevation Scan Unit

17. COST 723 Training School - Cargese 4 - 14 October 2005 Interferometer Beamsplitter Corner Cube

18. COST 723 Training School - Cargese 4 - 14 October 2005 Interferometer characteristics Cooled instrument Optical compensation of alignment errors Double sided interferograms Double input and double output

19. COST 723 Training School - Cargese 4 - 14 October 2005 O MIPAS on ENVISAT

20. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS Observation Principle

21. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS measurement scenario Characteristics:  sweep duration: 4.45 s (full resolution)  sweeps per limb seq.:17 (68km, 60km, 52km, 47km, (42 – 6) km in 3 km steps  # limb seq. per orbit: ~ 75 (deep space cal. every 5 sequences)  azimuth scan range: ~ +/-15 0  rearward geometries: global coverage, poles visible

22. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS coverage in one orbit

23. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS coverage in one day

24. COST 723 Training School - Cargese 4 - 14 October 2005 MIPAS coverage in three days

25. COST 723 Training School - Cargese 4 - 14 October 2005 -110° long66° long-85° long91° long-60° long116° long-35° long141° long-9° long166° long16° long-160° long41° long-135° long12 h measurements 0 10 ppm 5 Ozone vertical distribution as a function of latitude and longitude

26. COST 723 Training School - Cargese 4 - 14 October 2005 8 km11 km14 km17 km20 km23 km26 km29 km32 km35 km38 km41 km44 km47 km50 km53 km 8 - 53 km 0 5 10 ppm 3D global ozone distribution

27. COST 723 Training School - Cargese 4 - 14 October 2005 AIRS: Atmospheric InfraRed Sounder Agency: NASA Satellite: AQUA Launched on the 4 th of May 2002. Operating AIRS overview

28. COST 723 Training School - Cargese 4 - 14 October 2005 AIRS AIRS is a grating nadir-looking instruments. 3 IR wavebands (from 3.74 µm to 15.4µm) with a total of 2378 channels at spectral resolution < 1cm -1. 4 Vis/NIR channels (from 0.4 µm to 1.1 µm). IFOV 13.5km at nadir

29. COST 723 Training School - Cargese 4 - 14 October 2005 ACE overview ACE: Atmospheric Chemistry Experiment Agency: Canadian Space Agency Satellite: SCISAT-1 Launched on 12 th August 2003. Operating.

30. COST 723 Training School - Cargese 4 - 14 October 2005 ACE ACE is a high spectral resolution (0.02 cm-1) occultation FT spectrometer operating from 750–4400 cm -1 (about from 2.2 to 13.3 µm) with a spectral resolution of 0.02 cm -1.

31. COST 723 Training School - Cargese 4 - 14 October 2005 TES: Tropospheric Emission Spectrometer Agency: NASA Satellite: AURA Launched on 15 th July 2004. Operating. TES overview

32. COST 723 Training School - Cargese 4 - 14 October 2005 TES TES is an infrared-imaging Fourier transform spectrometer operating in a combination of limb and nadir modes.

33. COST 723 Training School - Cargese 4 - 14 October 2005 TES TES is an infrared-imaging Fourier transform spectrometer operating in a combination of limb and nadir modes. Spectral range 650 – 3050 cm -1 (about 3.3 – 15.4  m). Spectral resolution 0.02 cm -1

34. COST 723 Training School - Cargese 4 - 14 October 2005 TES TES is an infrared-imaging Fourier transform spectrometer operating in a combination of limb and nadir modes. 1x16 element focal plane arrays

35. COST 723 Training School - Cargese 4 - 14 October 2005 HIRDLS: High Resolution Dynamics Limb Sounder Agency: NASA-UK Satellite: AURA Launched on 15 th July 2004. Operating. HIRDLS overview

36. COST 723 Training School - Cargese 4 - 14 October 2005 HIRDLS HIRDLS is a multi-channel limb-viewing infrared (IR) radiometer operating in the spectral range from 6 to 18  m

37. COST 723 Training School - Cargese 4 - 14 October 2005 IASI overview IASI: Infrared Atmospheric Sounding Interferometer Agency: CNES Satellite: Metop 1, 2 and 3 by EUMETSAT Launch scheduled for 2006, 2010 and 2015.

38. COST 723 Training School - Cargese 4 - 14 October 2005 IASI IASI is a nadir-sounding imaging FT spectrometer operating in the spectral range 645 to 2760 cm -1 (15.5 to 3.62 µm) with a spectral resolution of 0.25 cm -1. IFOV=10 mrad (8x8 km 2 footprint). A 2 x 2 array in each of its three bands.

39. COST 723 Training School - Cargese 4 - 14 October 2005 CrIS overview CrIS: Cross-track Infrared Sounder Agency: NOAA Satellite: NPOESS (National Polar-orbiting Operational Environmental Satellite System) Launch scheduled for 2008.

40. COST 723 Training School - Cargese 4 - 14 October 2005 CrIS CrIS is an imaging interfereometer with a 3 x 3 array covering 3 bands over a spectral range of 3.92 µm to 15.38 µm (650 cm -1 to 2550 cm -1 ).The instrument resolution varies from 0.625 cm -1 to 2.5 cm -1. Picture of prototype

41. COST 723 Training School - Cargese 4 - 14 October 2005 GIFTS overview GIFTS: Geosynchronous Imaging Fourier Transform Spectrometer. Agency: NASA Satellite: GIFTS-IOMI Launch scheduled for ??.

42. COST 723 Training School - Cargese 4 - 14 October 2005 GIFTS GIFTS is a geostationary, nadir sounding, imaging interferometer with a detector arrays 128 x 128, operating in the spectral ranges 685 - 1130 cm -1 and 1650 - 2250 cm -1 with a spectral resolution of 0.6 cm -1.

43. COST 723 Training School - Cargese 4 - 14 October 2005 GGOS overview GGOS: Greenhouse Gas Observing Sensor Agency: JAXA Satellite: GOSAT Launch scheduled for August 2008.

44. COST 723 Training School - Cargese 4 - 14 October 2005 Greenhouse Gas Observing Sensor The Greenhouse Gas Observing Sensor is a nadir-sounding FT spectrometer operating in the visible (three bands) and in the spectral range 645 to 2760 cm -1 (14.3 to 0.75 µm) with a spectral resolution from 0.5 to 0.2 cm -1. IFOV 10 km

45. COST 723 Training School - Cargese 4 - 14 October 2005 REFIR REFIR is a nadir-sounding FT spectrometer operating from balloon in the spectral range from 100 to 1400 cm -1 with a spectral resolution of 0.5 cm -1. Room temperature detectors. First balloon flight on 1 st July 2005

46. COST 723 Training School - Cargese 4 - 14 October 2005 Summary of recent and planned missions

47. COST 723 Training School - Cargese 4 - 14 October 2005 spectral resolution General considerations spectral resolution On going evolution from radiometers to multichannel grating spectrometer, and to high resolution FT spectrometers. Data analysis is performed with either channel or microwindow selection

48. COST 723 Training School - Cargese 4 - 14 October 2005 emission measurements General considerations emission measurements Few missions use occultation measurements, which, with their high S/N, are best suited for the understanding of radiative transfer. Most of the new mission use emission measurements, which, with their continuous and global coverage, are best suited for the understanding of atmospheric processes. Thermal radiation

49. COST 723 Training School - Cargese 4 - 14 October 2005 imaging General considerations imaging Array detectors are providing imaging capabilities to FT spectrsocpy. IASITES

50. COST 723 Training School - Cargese 4 - 14 October 2005 spatial resolution General considerations spatial resolution The large number of observations (both in space and spectral domain) improve the conditioning of the inversion problem. In nadir sounding the good conditioning can be exploited for attaining 1 km vertical resolution. In limb sounding the good conditioning can be exploited for attaining 50 km horizontal resolution.

51. COST 723 Training School - Cargese 4 - 14 October 2005 spacecraft orbit General considerations spacecraft orbit Polar platforms are usually the preferred choice because of global coverage requirements. Meteorological and now- casting applications require frequent observations from geostationary platforms.