The 2001 Update of the GEISA-97 Spectroscopic Database
System
General Context
High resolution vertical infrared sounding new instruments, like AIRS (Atmospheric Infrared
Sounder: http://www-airs.jpl.nasa.gov/) in the USA, and IASI (Infrared Atmospheric Sounding
Interferometer: http://www-projet.cst.cnes.fr:8060/IASI/index.html) in Europe, which have a better
vertical resolution and accuracy compared to the presently existing ones, will mainly be devoted to
operational meteorology associated with Numerical Weather Prediction, with the purpose of providing
an improved knowledge of the vertical atmospheric structure and of surface properties.
The performances of these second generation vertical sounders will be highly dependent on the
accuracy to which the spectroscopic parameters of the optically active atmospheric gases are known,
since these are essential input in the forward models used to simulate recorded radiance spectra.
Consequently, there is a strong requirement for a comprehensive, validated and operational, interactive
spectroscopic database. In this context, since 1974 the ARA (Atmospheric Radiation Analysis) group
at LMD (Laboratoire de Météorologie Dynamique, France) has developed the GEISA (Gestion et
Etude des Informations Spectroscopiques Atmosphériques: Management and Study of Atmospheric
Spectroscopic Information) computer accessible database system (Chédin et al. 1982; Husson et al.
1992,1994), to perform reliable radiative transfer calculations, using « line-by-line and layer-bylayer » approach for fast forward radiative transfer modelling. This effort benefits the communities
doing direct and inverse radiative transfer studies. Currently, GEISA is involved in activities related to
the assessment of improved atmospheric sounders capabilities, as described in Jacquinet-Husson et al.
(1998).
GEISA Spectroscopic Database Overview
The GEISA database, in its 1997 version (GEISA-97), is extensively described in JacquinetHusson et al. (1999). It has been partially updated in 2001 (GEISA-01). The GEISA-01 system
comprises three sub-databases, i.e.:

The GEISA-01 sub-database on line transition parameters:
GEISA-01 line transition parameters sub-database involves 42 molecules (96 isotopic species) and
contains 1,361,667 entries (15,401 supplementary entries since GEISA-97), between 0 and 22,656 cm1
.
The included molecules are of interest for the Earth and other Planet atmospheres (such as: C 2H4,
GeH4, C3H8, C2N2, C4H2, HC3N, H2S, HCOOH and C3H4, for the Giant Planets). Among the
spectroscopic parameters archived in GEISA, the most important for atmospheric radiative transfer
modelling are: the wavenumber (cm-1) of the line associated with a vibro-rotational transition, the
intensity of the line (cm molecule-1 at 296K), the Lorentzian collision halfwidth (cm-1 atm-1 at 296 K),
the energy of the lower level of the transition (cm-1), the transition quantum identifications for the
lower and upper levels of the transition, the temperature dependence coefficient of the halfwidth, the
database management identification codes for isotopes and for molecules. These parameters are stored
following the GEISA usual standard as described in Jacquinet-Husson et al. (1999).
A summary of GEISA-01 line transition parameters sub-database content is given in Table 1. The
molecular species formula are listed in column 1 and the molecules and isotopes identification codes
for the database management in column 2 and 3, respectively; the numbers of transitions for each
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molecule are in column four.
Table 1: Summarized Content of the GEISA-01 Line Transition Parameters Sub-database
MOLECULE
CODE
ISOTOPE
NUMBER OF TRANSITIONS
H2O
1
161-162-171-181-182
52188
CO2
2
626-627-628-636-637-638-728-828-838
76364
O3
3
666-668-686-667-676
281607
N2O
4
446-447-448-456-546
26653
CO
5
26- 36- 28- 27- 38- 37
13515
CH4
6
211-311
66883
O2
7
66- 67- 68
6292
NO
8
46- 48- 56
94738
SO2
9
626-646
38853
NO2
10
646
100680
NH3
11
411-511
11152
PH3
12
131
4635
HNO3
13
146
171504
OH
14
61- 62- 81
41786
HF
15
19
107
HCl
16
15-17
533
HBR
17
11-19
576
HI
18
17
237
ClO
19
56-76
7230
OCS
20
622-624-632-623-822-634-722
24922
H2CO
21
126-128-136
2702
C2H6
22
226-236
14981
CH3D
23
212
11524
C2H2
24
221-231
1668
C2H4
25
211-311
12978
GeH4
26
411
824
HCN
27
124-125-134
2575
C3H8
28
221
9019
C2N2
29
224
2577
C4H2
30
211
1405
HC3N
31
124
2027
HOCl
32
165-167
15565
N2
33
44
117
CH3Cl
34
215-217
9355
H2O2
35
166
100781
H2S
36
121-141-131
20788
HCOOH
37
261
3388
COF2
38
269
54866
SF6
9
29
11520
C3H4
40
341
3390
HO2
41
166
26963
ClONO2
42
564-764
32199
____________________________________________________________________________________________________
TOTAL
1,361,667
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Three molecules (underlined in Table 1) have been updated in GEISA-01, i.e.:
H2O: 10,755 transitions by Toth (1998, 1999a, 1999b, 1999c, 1999d, 2000a, 2000b), and Toth et
al. (1998), have replaced the corresponding existing ones, in the spectral range 500 – 2900
cm-1 ;
CO2: 48,000 new transitions by Tashkun et al. (2000), Teffo et al. (2000) and Teffo (2001), have
replaced the corresponding existing ones, in the spectral range 430 - 2820 cm-1 ;
N2O: a technical update has removed 118 duplicated lines in the spectral interval 564 cm-1 - 629
cm-1.

The GEISA-01 sub-database on absorption cross-sections:
Besides the line transition parameters data catalog itself, GEISA includes, in the spectral
range 556.380-1763.642 cm-1, a second catalog, referred to as GEISA_CROSS, providing, at
various temperatures and pressures, the cross-sections of species exhibiting dense spectra , not
suitable for a discrete parameterized format. This represents 4,716,743 entries related to 23
molecules, i.e.: CFC11, CFC12, CFC13, CFC14, CFC113, CFC114, CFC115, HCFC22,
HCFC123, HCFC124, HFC125, HFC134a, HCFC141b, HCFC142b, HFC152a, HCFC225ca,
HCFC225cb, HFC32, HFC143a, HFC134, N2O5, SF6, ClONO2.
The absorption cross-sections are determined through the following expression:
 ( ) 
ln[ I 0 ( ) / I ( )]
nl
where  is the wavenumber (cm-1); () is the absorption cross-section (cm2 molecule-1); I0( ) and
I( ) are the intensities, at the frequency , of the incident and transmitted radiation, respectively; n is
the concentration of the molecules (molecule cm-3) and l the optical path length (cm). It is the ()
value, derived from high-resolution experimental data, that is cataloged in the GEISA cross-sections
file.
Examples of the direct image of GEISA_CROSS line records are given in Table 2. For each of the
listed entries is provided the FORTRAN format of: the wavenumber,  (cm-1), in column one; the
absorption cross-section value, () (cm2 molecule-1), in column 2; the internal identification code,
M, of the actual molecule, in column 3 and the code C related to the atmospheric conditions (T and P),
in column 4. There is a total of 108 atmospheric condition codes. Examples of some of these codes are
listed in Table 3, where the atmospheric condition codes C are in column one, and the temperature T
(in K) and pressure P (in Pa) in columns 2 and 3 respectively.
A management program, supplied with GEISA_CROSS, has been designed to use and manage this
sub-database.
No update occurred since the GEISA-97 Edition.

The GEISA-01 sub-database on micro-physical and optical properties of atmospheric
aerosols.
This new GEISA-01 edition sub-database on micro-physical and optical properties of atmospheric
aerosols is described in the next section (GEISA/IASI database).
Users friendly management softwares (Chédin et al. 1986; Husson et al. 1994) are associated with
each of these three GEISA-01 sub-databases catalog. The current edition of the GEISA system, with
associated softwares, are accessible freely via the ARA/LMD group workstations Web site, upon prior
request for password at: http://ara.lmd.polytechnique.fr/registration. Give registerme as user’s
name. No password is required at this stage of the access.
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Table 2: GEISA_CROSS Line Records Format


1186.00232
1.062E-20
12
62
1186.00232
1.616E-21
12
56
1186.00232
1.768E-20
12
60
1186.00232
2.302E-20
12
61
1186.00232
4.130E-21
12
63
M
C
FORMAT(F10.6, E10.3, I3, I3) corresponding to:
 F10.6 Frequency in cm-1
F10.5
for frequencies  1000 cm-1
 E10.3
Absorption cross-section in cm2 mol-1
M I3
Molecule identification code
C
Atmospheric condition code
I3

Table 3: Example of GEISA_CROSS
Atmos
pheric Condition Codes
C
T
P
1
296.0
101325.00
2
283.8
94658.88
3
283.8
81326.64
4
283.9
69460.95
5
272.5
101325.00
6
272.5
87992.76
7
272.5
73327.30
8
272.5
61328.29
C - code of atmospheric conditions
T - temperature in K
P - pressure in Pa
GEISA/IASI-01 Sub-database on Micro-physical and Optical Properties of Atmospheric
Aerosols
Besides the molecular species which define the gaseous infrared opacity in the Earth’s atmosphere
aerosol particles however also contribute to this opacity. Consequently, a common GEISA and
GEISA/IASI aerosol sub-database, referred to as GEISA_AEROS, has been recently elaborated. It
gathers the micro-physical and optical properties from four published aerosol data catalogs, i.e.:
Massie (1994), Rublev (1994), Hess (1998), Köpke (1997), the overall content of which deals with the
archive of complex refractive indices and possibly computed optical related properties, for selected
basic aerosol components. Softwares for data management and user-selected aerosol mixtures
elaboration are available from Rublev (1994), Hess et al. (1998), Köpke et al. (1997).
GEISA_AEROS consists in the following:
1. A database on refractive indices of 10 varieties of basic aerosol components (Massie,
1994, 2000)
This database recently updated (Massie, 2000) since its origin (Massie, 1994) comprises an
extensive archive of complex refractive indices, determined both in situ and in the laboratory, from
spectral transmission and reflection measurements (over 40 references), of various aerosol
components, i.e.: organic-based non-volatile aerosols from 525 to 5000 cm-1, water ice from 800 to
4004 cm-1, aqueous HNO3/H2O from 754 to 4700 cm-1, nitric acid trihydrate (NAT) from 711 to 4004
cm-1, nitric acid dihydrate (NAD) from 700 to 4700 cm-1, liquid H2SO4/H2O from 825 to 4700 cm-1,
liquid H2SO4/H2O from 499 to 6996 cm-1, liquid HNO3/H2O from 250 to 4987 cm-1.
2. A database microphysical and optical properties of atmospheric aerosols (Rublev 1994)
The first part of the archive consists in complex indices of refraction of seven basic aerosol
components, from Zolatarev (1984), i.e.: dust-like, water-soluble, soot, and oceanic salt particles,
sulfuric acid solution droplets, volcanic ash, and water, which have been used in Rublev (1994) for the
computation of aerosol integrated optical properties (extinction coefficient, single scattering albedo,
asymmetry factor) for:
- Four basic aerosol components: dust-like, water-soluble, soot, and oceanic salt particles;
- Six principal aerosol models: continental, urban, maritime, stratospheric, volcanic, upper
atmosphere, and cloudy, as defined in WMO (1986).
In the second part, the so-called AERCOMP (FORTRAN code) software package (Rublev, 1994),
allowing the determination of optical properties for user-defined aerosol mixtures, has been archived
with its associated basic aerosol constituent optical properties (including scattering phase functions, as
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well) files.
3. The database and associated software package OPAC (Optical Properties of Aerosols
and Clouds) by Hess et al. 1998.
The first part of this archive is a data set of microphysical properties and the resulting optical
properties of:
- Ten basic aerosol components: insoluble, soot, water soluble, two sea salt modes - various kinds of
salt contained in seawater-, three mineral modes - mixture of quartz and clay minerals-, mineral
transported, sulfate droplets. The refractive indices of the aerosol components used in the
computations are essentially from d’Almeida et al. (1991) which partly refer to Shettle and Fenn
(1979), in few cases corrected with respect to different sources, Köpke et al. (1997).
- Six water clouds: stratus (continental and maritime), cumulus (continental -clean and polluted- and
maritime), fog, and three kinds of cirrus ice clouds, both in the solar and terrestrial spectral range.
The second part is a FORTRAN program making it possible to extract data from the above archive
and allowing calculation of any user-defined mixtures of these components. A set of computed typical
mixtures is archived, as well.
4. The Global Aerosol Data Set GADS (Köpke et al. 1997).
Global fields of all optical parameters necessary for an estimate of the radiative forcing by aerosol
particles and to quantify the resulting climate effects are not available from measurements due to the
multiple influence parameters. Therefore, using the OPAC aerosol archive, GADS provides the related
global aerosol distribution as climatologically averaged values both for the winter (December through
February) and summer (June through August) seasons on a global grid with a resolution of 5° by 5°
longitude and latitude, independently for the components selected in OPAC. The data are presented as
global maps of the aerosol in the first layer above the surface (the first atmospheric layer above the
ground that is assumed to be well mixed). The global maps of the 10 selected aerosol components
have been obtained through estimates and analysis of a large number of different measurements and
model simulations. More details on the archived files structure is given in Köpke et al. (1997). A
GADS database associated FORTRAN program has been designed to manage the archived data and to
make it possible to calculate the global distributions of user- selected aerosol optical or microphysical
properties.
The common GEISA and GEISA/IASI-01 sub-database on micro-physical and optical properties of
atmospheric aerosols is available at: http://ara.lmd.polytechnique.fr/aero, after GEISA access
registration.
The GEISA/IASI spectroscopic database system described above, including data files and
management softwares, is available at:
ftp://ara01.lmd.polytechnique.fr/pub/geisa/iasi2001
References
D’ Almeida, G.A., Köpke, P. and Shettle, E.P. 1991. Atmospheric aerosols : global
climatology and radiative characteristics. A. Deepak Publishing, Hampton, Va.
Brown, L.R. 2000. Private communication.
Brown, L.R. 2001. Private communication.
Chédin, A., Husson, N. and Scott, N.A. 1982. Une banque de données pour l’étude
des phénomènes de transfert radiatif dans les atmosphères planétaires: la banque
« GEISA ». Bulletin d’Information du Centre de Données Stellaires (France), 22,
121-121.
Chédin, A., Husson, N., Scott, N.A., Cohen-Hallaleh, I. and Berroir, A. 1986. The
GEISA data bank 1984 version. Internal Note LMD, n° 127, February 1985,
reviewed october 1986
Clerbaux, C., Colin, R., Simon, P.C. and Granier, C. 1993. Infrared cross-sections and global
warming potentials of 10 alternative hydrohalocarbons. Journal of Geophysical
Research, , 98, D6, 10491-10497.
16/02/16 07:38
D:\533562676.doc
De Backer-Billy, M-R and Barbe, A. 2001. Absolute intensities of the 10m bands of 16O3. JMS.
205, 43-53.
DLR, 2001. Private Communication.
Devi, V.M., D.C. Benner, D.C., Smith, M.A.H., et al. 1991. Measurements of air-broadened,
N2-broadened, N2-broadened and O2-broadened half-widths and pressure-induced line
shifts in the 3 of CH4 –C-134. Applied Optics, 30, 287-304.
Fejard, L., Champion, J.P., Jouvard, J.M., Brown, L.R. and Pine, A.S. 2000: The intensities of
Methane in the 3-5 m region revisited. JMS, 201, 83-94.
Goldman A., Rinsland, C.P., Perrin, A. and J.M. Flaud. 1998. HNO3 line parameters: 1996 HITRAN
update and new results. JQSRT, 60, 851-861.
Goldman A. 2001. Private communication.
Hess, M., P. Köpke, P. and I. Schult. 1998. Optical Properties of aerosols and clouds : the
software package OPAC. BAMS, 79, N°.5, 831-844.
Hilico, J.C., Champion, J.P., Toumi, S., Tyuterev, Vl.G. and S.A. Tashkun. 1994. New analysis of
the pentad system of Methane and prediction of the (pentad-pentad) spectrum. JMS.
168, 455-476.
Hilico, J.C., Robert, O., Loete, M., Toumi, S., Pine, A.S., and Brown, L.R. 2001. JMS (in Press)
Husson, N., Bonnet, B., Scott, N.A. and A. Chédin, 1992. Management and study of
spectroscopic information: the GEISA program. JQSRT, 48, 509-518.
Husson, N., Bonnet, B., Chédin, A., Scott, N. A, Chursin, A. A., Golovko, V. F. and Tyuterev,
Vl.G. 1994: The GEISA data bank in 1993. A PC/AT compatible computers’ new
version. JQSRT, 52, 425-438
Jacquinet-Husson, N., Scott, N. A., Chédin, A., Bonnet, B., Barbe, A., Tyuterev, Vl. G.,
Champion, J. P., Winnewisser, M., Brown, L. R., Gamache, R., Golovko, V. F. and
Chursin, A.A. 1998. The GEISA system in 1996: Toward an operational tool for the
second generation vertical sounders radiance simulation. JQSRT, 59, 511-527.
Jacquinet-Husson, N. Arié, E., Ballard, J., Barbe, A., Brown, L.R., Bonnet, B., Camy-Peyret, C.,
Champion, J.P., Chédin, A., Chursin, A., Clerbaux, C., Duxbury, G., Flaud, J.-M.,
Fourrié, N., Fayt, A., Graner, G., Gamache, R., Goldman, A., Golovko, Vl, Guelachvilli,
G., Hartmann, J.M., Hilico, J.C., Lefèvre, G., Naumenko, O.V., Nemtchinov, V.,
Newham, D.A., Nikitin, A., Orphal, J., Perrin, A., Reuter, D.C., Rosenmann, L.,
Rothman, L.S., Scoot, N.A., Selby, J., Sinitsa, L.N., Sirota, J.M., Smith, A.M., Smith,
K.M., Tyuterev, Vl.G., Tipping, R.H., Urban, S., Varanasi, P., and Weber, M. 1999. The
1997 spectroscopic GEISA databank. JQSRT,62, 205-254.
Jacquinet-Husson, N., Scott, N.A., Chédin, A. and Chursin, A.A. 2001. The GEISA-97
spectroscopic database system : its present and future. In IRS 2000: Current Problems
in Atmospheric Radiation, W.L. Smith and Y. Timofeyev Eds. A. Deepak Publ.,
Hampton, 2000, 147, 663-667.
Jouvard, J.M., Lavorel, B., Champion, J.P. and L.R. Brown. 1991. Preliminary analysis of the
pentad of 13CH4 from Raman and infrared spectra. JMS. 150, 201-217.
Köpke P., Hess, M., Schult, I. and Shettle, E.P. 1997. Global Aerosol Dataset. Max-PlanckInstitut für Meteorologie. Report N°. 243, Hamburg, Germany.
Li, Z. and Varanasi, P. 1994. Measurement of the absorption cross-sections of CFC-11 at
conditions representing various model atmospheres. JQSRT. 52, 137-144.
Mandin J.Y., Dana V. and Claveau, C. 2000. Line intensities in the 5 band of acethylene 12C2H2.
JQSRT. 67, 429-446.
Mandin J.Y and V. Dana, V. 2001. Private communication.
Massie, S.T. 1994. Indices of refraction for the HITRAN compilation. JQSRT, 52, 501-513.
Massie, S.T. 2000. Private Communication.
Nikitin, A., Champion, J.P., Tyuterev, Vl.G., Brown, L.R., Mellau, G. and Lock, M. 2000.
The infrared spectrum of CH3D between 900 and 3200 cm-1; extended
assignment and modeling. J. Mol. Struct. 517, 1-24.
Ouardi, O., Hilico, J.C., Loete, M. and Brown, L.R. 1996. The hot bands of Methane between
5 and 10 m. JMS. 180, 311-322.
16/02/16 07:38
D:\533562676.doc
Rublev, A. A. 1994. Algorithm and computation of aerosol phase functions. Internal
Note IAE-5715/16 of Russian Research Center . Kurchatov Institute,
Moscow, Russia.
Shettle, E.P. and Fenn, R.W. 1979. Models for the aerosols of the lower atmosphere and the effects
of humidity variations on their optical properties, AFGL-TR-79-0214.
Smith, M.A.H., Rinsland, C.P., Devi, V.M., and Benner, D.C. 1992. Temperature-dependence of
broadening and shifts of methane lines in the 4 band.
Spectroch. Acta. 48 A, 1257-1272.
Tashkun, S.A., Perevalov, V.I., Teffo, J.L., Rothman, L.S., and Tyuterev, Vl.G. 1998. Global fitting
of 12C16O2 vibrational-rotational line positions using the effective Hamiltonian approach.
JQSRT, 60, 785-801.
Tashkun, S.A., Perevalov, V.I., Teffo, J.L., Tyuterev, Vl.G. 1999. Global fit of 12C16O2 vibrationalrotational line intensities using the effective operator approach. JQSRT, 62, 571-598.
Tashkun, S.A., Perevalov, V.I., Teffo, J.L., Lecoutre, M., Huet, T.R., Campargue, A., Bailly, D. and
Esplin, M.P. 2000. 13C16O2: Global treatment of vibrational-rotational spectra and first
observation of the 21+53 and 1+22+53 absorption bands. JMS, 200, 162-176.
Teffo, J.L., Claveau, C., Kou, Q., Guelachvilli, G., Ubelman, A., Perevalov, V.I., and Tashkun, S.A.
2000. Line intensities of 12C16O2 in the 1.2-1.4 m spectral region. JMS, 201, 249-255.
Teffo, J.L. 2001. Private communication.
Toth, R.A. 1998. Water Vapor Measurements between 590 and 2582 cm-1: line positions and
Strengths. JMS, 190, 379-396.
Toth, R.A., Brown, L.R. and Plymate, C. 1998. Self-broadened widths and frequency shifts of water
vapor lines between 590 and 2400 cm-1. JQSRT, 59, 529-562.
Toth, R.A. 1999a. Analysis of line positions and strengths of H2O16 ground and hot bands
connecting to interacting upper states: (020), (100), and (001). JMS, 194, 28-42.
Toth, R.A. 1999b. HDO and D2O low pressure, long path spectra in the 600-3100 cm-1 region, I)
HDO Line positions and Strengths. JMS, 195, 73-97.
Toth, R.A. 1999c. HDO and D2O low Pressure, long path spectra in the 600-3100 cm-1 region, I)
D2O line positions and strengths. JMS, 195, 98-122.
Toth, R.A. 1999d. Air- and N2- Broadening Parameters of HDO and D2O, 709 to 1936 cm-1. JMS,
198, 358-370.
Toth, R.A. 2000a. Air- and N2- Broadening Parameters of water vapor: 604 to 2271 cm-1. JMS, 201,
218-243.
Toth, R.A. 2000b. Private communication.
Varanasi, P. and Nemtchinov, V. 1994. Thermal infrared absorption coefficients of
CFC-12 at atmospheric conditions. JQSRT, 51, 679-687.
Varanasi, P. et al. 1999a. Private communication.
Varanasi, P.et al. 1999b. Private communication.
Wagner, G. 2000. Private communication.
Wagner, G., Birk, M., Schreier, F. and Flaud, J.M. 2001. Spectroscopic data of the three Ozone
fundamentals. (In press).
World Climate Research Program. 1986. WCP-112, WMO/TD, No 24.
Zolatarev, V.M., Morozov,V.M. and E.V. Smirnova, E.V. 1984. Optical constants of natural and
technology media (in Russian). Leningrad, 1984, 216 pp.
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