What's New

monoRTM Version	Release Date	Notes
v5.6	October 2021	This release fixed a number of errors in the CO2 line shape calculation code. Both the CO2 pedestal and the line coupling equations were corrected (E. Mlawer,K.Cady-Pereira)
v5.5	July 2021	The continuum was updated to MT_CKD_3.5, which includes improvements in the water vapor continuum from the microwave through the far-infrared (E. Mlawer, V. Payne, J. Mascio, D. Turner), and a bug fix in the O2 A-Band continuum (E. Mlawer, J. Mascio, E. Magee)
v5.4	August 2017	The continuum was updated to MT_CKD_3.2, which has new self continnum coefficients in window regions for wavenumbers greater than 2000 cm-1 and updated self continuum temperature dependence from 1800-3500 cm-1 (E.J. Mlawer, M.J. Alvarado, K.E. Cady-Pereira). Corrected TKC coeffs in the CloudOptProperties routine (David Turner, Karen Cady-Pereira)
v5.3	March 2017	The continuum has been updated to MT_CKD v3.0, which included modifications to the H2O foreign continuum from 0-600 cm-1 and the self continuum in the microwave that resulted from an analysis of measurements taken at the ARM RHUBC-II campaign and a re-analysis of RHUBC-I measurements. (E.J. Mlawer, D.D. Turner, S.N. Paine, V.H. Payne) LNFL_v3.0 code now includes all the capabilities of MonoLNFL. Therefore MonoLNFL is no longer distributed with MonoRTM. Users should build the spectroscopic parameter input file (TAPE3) with LNFL instead, which is included in the download package.
v5.2	October 2015	The model for computing cloud liquid water absorption coefficients was replaced. Prior versions used the model from Liebe, Hufford, and Manabe (1991). This version uses a new model from Turner, Kneifel, and Cadeddu (2015). The differences are small for temperatures above 0 deg C with frequencies below about 60 GHz. Differences may be large at higher frequencies and very large at lower temperatures. The new and old models now reside in a new module in CloudOptProp.f90. Subroutine modm uses a generic interface to obtain the cloud liquid water optical depth from one of the models in CloudOptProp, and that interface points to the new model by default. Several minor bugs were corrected: the CLW variable is now initialized and the spectral properties are read in starting 25 cm-1 to the left of the first requested spectral point. A new control parameter, IBRD, is now available. Setting IBRD to zero turns off the species specific broadening, significantly shortening the processing time. This is a reasonable option for users working in scenarios where these effects are small.
v5.0	December 2013	This release is a major update to MonoRTM_v4.2, containing significant structural and spectroscopic changes. Restructuring (K. Cady-Pereira, G. Uymin, A. Lipton) The code's spectroscopic line input structure and atmospheric profiling code were made more consistent with LBLRTM. Line parameters are now read from a binary TAPE3 file (as in LBLRTM) produced with MonoLNFL, which is now included in the MonoRTM package. All routines except tips_2003.f are now f90. The code to read in and store the spectroscopic data was removed from modm and is in a separate module: lnfl_mod.f90. The RT codes are also in a new module: RTMmono.f. Physical constants are all declared in one module, PhysConstants.f90, which also provides routines to access the values; geophysical parameters in another similar module, PlanetEarth.f90. Additional capabilities A number of new input and output options, including optional netcdf output with spectral layer optical depths, have been added. (K. Cady-Pereira, D. Berthiaume). The capability to utilize a speed-dependent Voigt line shape has been added using the approach of Boone et al. (2007; 2011) (M. Alvarado). The spectral region about line center in which the detailed Humlicek (1982) method is used to compute the line shape has been extended to provide greater accuracy (M. Alvarado, E. Mlawer, G. Villanueva). The capability to utilize available line broadening coefficients (width, temperature dependence, pressure shift) that are specific to a given pair of species was added (K. Cady-Pereira, E. Mlawer, M. Alvarado). The method to compute path lengths in the code's atmospheric module was changed to provide greater stability for cases with exceptionally high rates of change of refractive index with height (M. Alvarado, E. Mlawer, D. Turner, N. Miller). Mixing ratio inputs are now allowed for IATM=0 (K. Cady-Pereira, J. Delamere). A bug related to foreign broadening of oxygen transitions was fixed (E. Mlawer, M. Alvarado, K. Cady-Pereira). A bug related to the use of the continuum in MonoRTM for near-IR cases was fixed (K. Cady-Pereira, M. Alvarado). Spectroscopy The default microwave line parameter files, spectral_lines.dat.0_55.v5.0_fast and spectral_lines.dat.0_55.v5.0_veryfast, now have a direct correspondence to the full AER linelist, whose current version is aer_v_3.3 (M. Alvarado, K. Cady-Pereira, E. Mlawer). Numerous lines were added to the default microwave line files (M. Alvarado, E. Mlawer, K. Cady-Pereira) so that the calculational accuracy at any frequency between 0 and 899.4 GHz (0-30 cm-1) with respect to the full line list aer_v_3.3 is: for spectral_lines.dat.0_55.v5.0_fast (corresponds to ISPD=0 in MonoRTM v4.2 and older): 0.1 K for upwelling, 0.2 K for downwelling for spectral_lines.dat.0_55.v5.0_veryfast (corresponds to ISPD=1 in MonoRTM v4.2 and older): 0.5 K for upwelling, 1.0 K for downwelling NOTE: Users who wish to run MonoRTM v5.0 in spectral regions other than the MW should use the full AER line file (either aer_v_3.2 or aer_v_3.3), keeping in mind that the full line file can take a long time to run. Line parameters were taken from HITRAN 2012 with the exceptions noted below. 60 GHz O2 lines and 120 Ghz O2 line from Tretyakov et al. (2005), as implemented in MonoRTM v4.2. 0 cm-1 "Debye line" for O2 same as in MonoRTM v4.2, all other O2 lines below 1.497951 cm-1 removed. The intensities for the H2O lines at 0.7417 cm-1 (22.233 GHz), 6.1145 cm-1 (183.3 GHz), 10.84 cm-1 (325 GHz) and 12.68 cm-1 (380 GHz) are based on the work of S. A. Clough (1973) and are the same as in MonoRTM v4.2. The foreign widths of the 22 and 183 GHz water vapor lines were rederived based on HITRAN 2012 line parameters using the approach of Payne et al. (2009). The temperature dependence parameters for these lines were adjusted from their HITRAN 2012 values to provide better agreement with calculations by Gamache (V. Payne, B. Gamache, E. Mlawer). Broadening parameters were implemented for the following pairs of molecules: Oxygen transitions broadened by water vapor based on Drouin et al. (2013) (E. Mlawer, K. Cady-Pereira). Carbon dioxide transitions broadened by water vapor based on Sung (2009) (K. Cady-Pereira). Water vapor transitions broadened by carbon dioxide based on calculations by R. Gamache of U. Mass. Lowell (K. Cady-Pereira). Carbon dioxide transitions broadened by carbon dioxide based on calculations by R. Gamache of U. Mass. Lowell (K. Cady-Pereira). The continuum was updated to MT_CKD_2.5. Speed dependent parameters were implemented for CO2 transitions in the bands 68<-1 and 71<-1 (i.e., 30012<-00001 and 30013<-00001) following Devi et al. (2007a,b) (M. Alvarado).
v4.2		An error related to the print-out of total optical depths in the MonoRTM.OUT file was corrected.
v4.1		Code is now using MT_CKD_2.4 continuum, which includes significant updates to the self- and foreign-broadened water vapor continuum in the range 0 to 600 cm-1 (0 to 18 THz), based on new analyses of ARM measurements in the microwave and far-IR regions (Payne et al., 2011; Delamere et al., 2010). An error related to calculations for multiple profiles was corrected. Code has been modified to pass optical depth arrays between subroutines as arguments in order to improve modularity of the Monochromatic Optical Depth Model (MODM) module. In addition, the IOD option may now be used as a flag to output layer optical depths to ascii files.
v4.0		Code has been updated to allow monochromatic calculations at frequencies beyond the microwave region. These updates include the implementation of CO2 line coupling and the option to include cross-section molecules. Format of output files has been modified to accommodate this change. Calculation of the total internal partition sum has been updated to be consistent with the calculation in LBLRTM. MonoRTM now uses MT_CKD_2.1 continuum (previously was using CDK_2.4). An error in the nitrogen continuum has been corrected. The INP option has been replaced by the use of IATM=1 or IATM=0 (consistent with LBLRTM). A stand-alone IDL program is provided to convert ARM netCDF profiles into MonoRTM input format.
v3.3		directory structure has been changed to make it more consistent with LBLRTM the 22GHz and the 183GHz water vapor lines have been updated (Payne et al., 2008) the 325 GHz water vapor line has been updated to reflect CRB calculations by Gamache the 380 GHz water vapor line has been updated according to measurements by Koshelev et al. (2007) corrected error in surface reflectance code updated limb radiative transfer code
v3.0		code has been updated to allow scaling of profiles spectral line file has been modified to include new oxygen line widths and line-coupling coefficients from Tretyakov et al. (2005) more lines in the spectral line file are now included in the fast option, to increase accuracy at higher frequencies and lower water vapor amounts
v2.20		code has been restructured and made more robust new makefiles allow for the creation of single and double precision code on SGIs and on MacOSX
v2.12		a new LBLATM module has been added, which is consistent with the LBLATM module currently used by LBLRTM several minor coding inconsistencies, which led to compilation errors under some compilers, have been eliminated
v2.11		O2 line coupling parameters have been modified to yield significantly better agreement with MWRP measurements in the 50-60 GHz range code output contains more detailed information on the current version of the software and the spectral lines file