Optical Lookup Table Codes See end of document for documentation of sources and versions cvs co -r TAG_NAME -d radiation sandbox/colarco/radiation The (large) dust ellipsoid database is not in CVS Pete Colarco 16Jul2012 - TAG: radiation_0r96 - Update CARMA to produce sulfate style tables 13Jun2012 - TAG: radiation_0r95 - Update CARMA to produce similar phase function as GOCART style files - Add a new dust refractive index set that merges Colarco et al. 2002 (UV) with Kim et al. 2011 (SW) to Levoni et al. 1997 (LW) (v8, v9, v10) - Add Dubovik et al. spheroid shape distribution to dust code 22Mar2012 - TAG: radiation_0r94 - Update references in README - add P22 and P44 to Mie output 09Feb2012 - TAG: radiation_0r93 - Update README to note definitions of pmom 02Feb2012 - TAG: radiation_0r93 - Updates to how spikes are handled coming out of Mie code - Refining the number of sub-bins to compute over in Mie code integration - Incorporated Ellipsoid database of dust optical properties from TAMU group (see Meng et al. 2010; driver code is in sub-directory lib/dust) - Recommended set of optics tables are: BC.v1_2 - OPAC, Chin et al. 2002 OC.v1_2 - OPAC, Chin et al. 2002 SU.v3_2 - OPAC refractive index, Tang et al. growth curve, Chin et al. 2002 particle size properties, second bin for volcanic aerosols following V. Aquila DU.v5 - Ellipsoid database, Levoni refractive indices SS.v3_2 - OPAC, cap at 95% 25May2010 - add an example "XX" directory under geosMie - add a document "examples.pdf" at top level to illustrate how to use "XX" examples 24May2010 - all filenames generated are now labeled ".nc" instead of ".hdf" - add phase function moment output to BC/OC/SS/SU and partially for DU (all in geosMie path). See note below. - have also added various growth factor forms for SU/SS courtesy of Cynthia Randles July2008 - initial code checked in This set of codes will generate the lookup tables of aerosol optical properties used in GEOS-4/5 based on the methodology used to create the aerosol optical properties used in GOCART. There are four main pieces: 1) MIEV - This is a general purpose Mie calculator developed by Warren Wiscombe a long time ago (Wiscombe, W.J., Improve Mie scattering algorithms, Applied Optics, 19 (9), 1,505-1,509, 1980). I have modified MIEV to take as input the two parameters you need to run a Mie code (size parameter and refractive index) as well as the number of phase function moments desired (the inputList) and return a small file (mieout.dat) on executation containing the size parameter, extinction and scattering efficiencies, number of phase function moments, the 4 polarized phase function moments, the asymmetry parameter, and the backscattering amplitude. This structure permits multiple calls of the Mie code with simple I/O. See the contents of the directory MIEV and especially the MIEV.doc file provided with the code by the author. A simple Makefile will compile the code with your choice of compiler (it is F77 compatible). 2) Optical databases - We provide copies of the GADS/OPAC databases for cloud and optical properties. This dataset is courtesy of Michael Hess at LRZ-Muenchen and can be downloaded on the web at: http://www.lrz-muenchen.de/~uh234an/www/radaer/opac-des.html It is unfortunately quite an old dataset. From here we get certain growth factors and refractive indices for different aerosol species. See the subdirectory "gads". We also provide a copy of the HITRAN refractive index of water dataset in the "hitran" subdirectory. HITRAN is a big, complicated beasty. I think I downloaded the whole thing and stripped out just the Shettle.dat aerosol file and the refrac.water.txt file. More info on HITRAN is at http://cfa-www.harvard.edu/hitran/ 3) A simple library of idl codes is provided in the directory "lib/idl". These are used by the actual table codes described next. 4) The lookup table generation codes are provided in two sub-directories. "geosMie" - This set of codes generates the optical lookup tables for each of the aerosol species used in the model. See the respective BC/DU/OC/SS/SU sub-directories. Each sub-directory contains an IDL driver "gocart_??.pro" where "??" is the species (in lower case) and will produce the optical lookup table. I won't bother to describe the actual construction of the tables at this point. Suffice to say, for each species a particle size distribution (PSD) is constructed and the Mie code is run at each size bin of that PSD and the optical properties are integrated. Except for dust, the parameters come from the GADS/OPAC/HITRAN dataset. For dust we allow that combination as well (version 1) but then also generate optics with other assumptions of refractive indices and even with some data from Ping Yang for non-spherical dust optical properties. When the codes are runs, a duplicate copy of the lookup table optics_??.hdf is dropped in the "x" directory. "geosBands" - This piece of code generates the band integrated optical lookup tables used in the GEOS-5 radiation code for aerosol heating rates. It presumes that the geosMie tables are all generated. Go in here and run "gocart_bands.pro" and it will generate tables in the local directory as well as in the "x" directory. Phase function moments: I have added the ability to output the phase function moments to the look-up tables. Generally, I have previously created files with names like "optics_DU.v1.nc". I have now created files with names like "optics_DU.v1_pmom.nc". It should be understood that the values in the two files are identical *except* for the presence of the phase function moments in the "v1_pmom" style files. The Mie code was always computing the phase function moments, but I was never bothering to write them to the files. Caveats: - at the moment, I don't bother to prepare these on the band files - for geosMie/DU directory, this computation is only carried out on "v1" of the dust table, as it's the most straightforward. With a little work it could be extended to "v2". Later versions ("v3" and "v4") are based on Ping Yang's tables and don't provide me the phase function moments. Notes: Prior to running any of these codes, source the top-level setup.csh file to (i) compile the Mie code (go into MIEV and check the Makefile if it barfs on compilation; maybe you need to select a different compiler) and (ii) it sets your IDL path to use the "lib/idl" codes. Most of the lookup tables generate in a few 10s of minutes. The SS will take considerably longer on account of the large particle sizes and the RH dimension. The band averaged tables are composed very quickly since they come from the already generated lookup tables. Future: Wouldn't it be nice to have a radiative transfer code here (rt4, disort)? How about a radiative forcing calculator? PMOM The tables (may) contain the moments of the phase function expansion. The variable is called "pmom" and is dimensioned (npol,nmom,radius,rh,lambda). nmom = number of phase function moments in the file npol = index of the phase function quantity npol = 4 or 6 index moments of quantity ----- ------------------- 0 P11 1 P12 2 P33 3 P34 4 P22 5 P44 Note that for Mie based tables we only have npol = 4. For the ellipsoid tables we have npol = 6 and have appended the P22 and P44 as the last two indices. From symmetry, for Mie based tables we know P22 = P11 and P44 = P33. TABLE VERSIONING DOCUMENTATION There is a naming convention of sorts. Two sorts of tables of provided. optics_XX.vvv.nc opticsBands_XX.vvv.nc where "XX" is the species (DU, SU, SS, BC, OC) and "vvv" is a version indicator. "optics_XX" refers to tables on channels (wavelengths) suitable for radiance calculations, while "opticsBands_XX" refers to tables on the Chou/Suarez 18 bands used internally for aerosol forcing calculation. NOTE: in some older tables "vvv" is omitted. These are essentially the "v1" tables, although they may not be zero-diff. In some tables "vvv" contains a flag "pmom" which is used to indicate that phase function moments are included in the tables (needed for radiance calculations). Where those files exist there is a version where "vvv" omits "pmom" which is the same table but omitting the phase function moments (so, a smaller file). Beginning with TAG radiation_0r93 I only produce a single file which includes the phase function moments and I omit the "pmom" from the versioning tag. Nominally I'm describing the GOCART style files (geosMie and geosBands sub-directories). In some cases there are similar files for CARMA (carma_optics_XX and carma_opticsBands_XX). Not all versions may be on the system you are working with. Species: DU v11_2 radiation_0r96 OPAC refractive indices with Dubovik spheroids v10_2 radiation_0r95 Like v8, but use Ellipsoid and spheroid shapes from Dubovik v9_2 radiation_0r95 Like v8, but use Ellipsoid and Meng et al. shape v8_2 radiation_0r95 Merge Colarco/Kim shortwave with Levoni longwave, Mie v7_2 radiation_0r94 Like v7 but now include phase function at 180 as variable in table v6_2 radiation_0r94 Like v6 but now include phase function at 180 as variable in table, also 6 phase moments v5_2 radiation_0r94 Like v5 but now include phase function at 180 as variable in table v1_2 radiation_0r94 Like v1 but now include phase function at 180 as variable in table, also 6 phase moments v7 radiation_0r93 Ellipsoid database (Meng et al. 2010) using OPAC refractive indices Note: not all OPAC refractive indices are supported (in the longwave) so I cap to database v6 radiation_0r93 Levoni et al. (1997) refractive indices and spherical particles v5 radiation_0r93 Ellipsoid database (Meng et al. 2010) and Levoni et al. (1997) refractive indices v1 OPAC refractive indices, spherical particles v2 OPAC refractive indices, spherical particles *except* mr = 1.45 and mi = OPAC/3 for wavelength < 2.5 um *and* then replace refractive index in range 440 - 1020 nm with values from AERONET/OMI v3 OPAC refractive indices *but* read from older Ping Yang ellipsoid database (no pmom) v4 Refractive indices as in v2 *but* read from older Ping Yang ellipsoid database (no pmom) Species: SS v5_3 radiation_0r94 Like V5_2 but now include all 6 phase matrix elements and phase function at 180 v4_3 radiation_0r94 Like V4_2 but now include all 6 phase matrix elements and phase function at 180 v3_3 radiation_0r94 Like V3_2 but now include all 6 phase matrix elements and phase function at 180 v2_3 radiation_0r94 Like V2 but now include all 6 phase matrix elements and phase function at 180 v5_2 radiation_0r93 OPAC refractive indices and Tang growth curve, but with growth capped at 95% RH v4_2 radiation_0r93 OPAC refractive indices and Tang growth curve v3_2 radiation_0r93 OPAC refractive indices and Gerber growth curve, but with growth capped at 95% RH v2 OPAC refractive indices and Gerber growth curve v1 Don't use this (optics_SS.nc) Species: SU v4_3 radiation_0r94 Like v4_2 but now include all 6 phase matrix elements and phase function at 180; change volcanic size params v3_3 radiation_0r94 Like v3_2 but now include all 6 phase matrix elements and phase function at 180; change volcanic size params v2_3 radiation_0r94 Like v2 but now include all 6 phase matrix elements and phase function at 180; change volcanic size params v1_3 radiation_0r94 Like v1 but now include all 6 phase matrix elements and phase function at 180; change volcanic size params v4_2 radiation_0r93 Like v4_1 but with a second size bin suitable for volcanic sulfate aerosols after Aquila et al. 2012 v3_2 radiation_0r93 Like v3_1 but with a second size bin suitable for volcanic sulfate aerosols after Aquila et al. 2012 v4_1 Like v4 but updates definition of effective radius v3_1 Like v3 but updates definition of effective radius v1 OPAC refractive indices and growth curve v2 OPAC refractive indices and growth curve, cap growth at RH = 95% v3 OPAC refractive indices, Tang et al. 1997 growth curve v4 OPAC refractive indices, Tang et al. 1997 growth curve, cap growth at RH = 95% Species: BC v2_3 radiation_0r94 Like v2_2 but now include all 6 phase matrix elements and phase function at 180 v1_3 radiation_0r94 Like v1_2 but now include all 6 phase matrix elements and phase function at 180 v2_2 radiation_0r93 Like v2_1 but fix an error in how ripple spikes were detected v1_2 radiation_0r93 Like v1_1 but fix an error in how ripple spikes were detected v1_1 Like v1 but change sense of effective radius v2_1 Like v2 but change sense of effective radius v1 OPAC refractive indices and growth curve, Chin et al. 2002 particle properties v2 OPAC refractive indices and growth curve, Chin et al. 2002 particle properties, cap growth at RH = 95% Species: OC v2_3 radiation_0r94 Like v2_2 but now include all 6 phase matrix elements and phase function at 180 v1_3 radiation_0r94 Like v1_2 but now include all 6 phase matrix elements and phase function at 180 v2_2 radiation_0r93 Like v2_1 but fix an error in how ripple spikes were detected v1_2 radiation_0r93 Like v1_1 but fix an error in how ripple spikes were detected v1_1 Like v1 but change sense of effective radius v2_1 Like v2 but change sense of effective radius v1 OPAC refractive indices and growth curve, Chin et al. 2002 particle properties v2 OPAC refractive indices and growth curve, Chin et al. 2002 particle properties, cap growth at RH = 95% References [1] C. Levoni, M. Cervino, and R. Guzzi, “Atmospheric aerosol optical properties: a database of radiative characteristics for different components and classes,” Appl Optics, 1997. [2] I. Tang, A. Tridico, and K. Fung, “Thermodynamic and optical properties of sea salt aerosols,” J Geophys Res-Atmos, vol. 102, pp. 23269–23275, 1997. [3] S. Gong, L. Barrie, and J. Blanchet, “Modeling sea-salt aerosols in the atmosphere .1. Model development,” J Geophys Res-Atmos, vol. 102, no. 3, pp. 3805–3818, Jan. 1997. [4] M. Hess, P. Koepke, and I. Schult, “Optical properties of aerosols and clouds: The software package OPAC,” B Am Meteorol Soc, vol. 79, no. 5, pp. 831–844, Jan. 1998. [5] M. Chin, P. Ginoux, S. Kinne, O. Torres, B. Holben, B. Duncan, R. Martin, J. Logan, A. Higurashi, and T. Nakajima, “Tropospheric aerosol optical thickness from the GOCART model and comparisons with satellite and Sun photometer measurements,” J Atmos Sci, vol. 59, no. 3, pp. 461–483, Jan. 2002. [6] Z. Meng, P. Yang, G. W. Kattawar, L. Bi, K. N. Liou, and I. Laszlo, “Single-scattering properties of tri-axial ellipsoidal mineral dust aerosols: A database for application to radiative transfer calculations,” J Aerosol Sci, vol. 41, no. 5, pp. 501–512, Jan. 2010. [7] V. Aquila, “Dispersion of the volcanic sulfate cloud from a Mount Pinatubo-like eruption,” Dec. 2011. [8] O. Dubovik, A. Sinyuk, T. Lapyonok, B. N. Holben, M. Mishchenko, P. Yang, T. F. Eck, H. Volten, O. Muñoz, B. Veihelmann, W. J. van der Zande, J.-F. Leon, M. Sorokin, and I. Slutsker, “Application of spheroid models to account for aerosol particle nonsphericity in remote sensing of desert dust,” J Geophys Res, vol. 111, no. 11, 2006. [9] P. Colarco, O. Toon, O. Torres, and P. Rasch, “Determining the UV imaginary index of refraction of Saharan dust particles from Total Ozone Mapping Spectrometer data using a three-dimensional model of dust transport,” J Geophys Res-Atmos, vol. 107, pp. –, 2002. [10] D. Kim, M. Chin, H. Yu, T. F. Eck, A. Sinyuk, A. Smirnov, and B. N. Holben, “Dust optical properties over North Africa and Arabian Peninsula derived from the AERONET dataset,” Atmos Chem Phys, vol. 11, no. 20, pp. 10733–10741, 2011.