COSP user`s manual Version 1.3.1 - CFMIP
Contents
1. dem_c long_name dem_c _FillValue q4 Longwave emissivity of convective cloud at 10 5 micron 1 e 30f dem_c units float skt point skt long_name Skin temperature skt _FillValue 1 e 30f skt units K float sunlit point Day points sunlit long_name sunlit _FillValue 1 e 30f 17 sunlit units 1 float u_wind point u_wind long_name eastward_wind u_wind _FillValue 1 e 30f u_Wind units m s 1 float v_wind point v_wind long_name northward_wind v_wind _FillValue 1 e 30f v_wind units m s 1 float mr_ozone level point mr_ozone long_name mass_fraction_of_ozone_in_air mr_ozone _FillValue 1 e 30f mr_ozone units kg kg float emsfc_lw emsfc_lw long_name Surface emissivity at 10 5 micron fraction emsfc_lw _FillValue 1 e 30f emsfc_lw units 1 global attributes title COSP inputs UKMO N320L50 Conventions CF 1 0 description This is the CDL structure of the COSP input NetCDF file in 2D mode netcdf cosp_input_um_2d dimensions lon 17 lat 9 level 38 bnds 2 hydro 9 variables float lon lon lon axis X lon units degrees_east lon long_name longitude lon bounds lon_bnds float lat lat lat axis Y lat units degrees_north lat long_name latitude 18 lat bounds lat_bnds float lon_bnds lon bnds float lat_b2. flux_large_scale_cloud_snow fl_lssnow _FillValue 1 e 30f fl_lssnow units kg m 2 s 1 fl_lsgrpl level point fl_lsgrpl long_name flux_large_scale_cloud_graupel fl_lsgrpl _FillValue 1 e 30f fl_lsgrpl units kg m 2 s 1 fl_ccrain level point 16 fl_ccrain long_name flux_convective_cloud_rain fl_ccrain _FillValue kg m 2 s 1 1 e 30f fl_ccrain units float fl_ccsnow level point fl_ccsnow long_name flux_convective_cloud_snow fl_ccsnow _FillValue kg m 2 s 1 1 e 30f fl_ccsnow units float tca level point tca long_name total_cloud_amount tca _FillValue gag 1 e 30f tca units float cca level point cca long_name convective_cloud_amount cca _FillValue 0 1 1 e 30f cca units float Reff hydro level point Reff long_name hydrometeor_effective_radius Reff _FillValue m 1 e 30f float dtau_s level point dtau_s long_name Reff units Optical depth of stratiform cloud at 0 67 micron dtau_s _FillValue 1 e 30f dtau_s units 1 float dtau_c level point Optical depth of convective cloud at 0 67 micron dtau_c long_name dtau_c _FillValue 1 e 30f dtau_c units 1 float dem_s level point Longwave emissivity of stratiform cloud at 10 5 micron dem_s long_name dem_s _FillValue 1 e 30f dem_s units 1 float dem_c level point
3. Flags for MODIS simulator outputs Lclhmodis MODIS High Level Cloud Fraction Lclimodis MODIS Ice Cloud Fraction Lcllmodis MODIS Low Level Cloud Fraction Lelmmodis MODIS Mid Level Cloud Fraction Lclmodis MODIS Cloud Area Fraction Lcltmodis MODIS Total Cloud Fraction Lclwmodis MODIS Liquid Cloud Fraction Liwpmodis MODIS Cloud Ice Water Path Llwpmodis MODIS Cloud Liquid Water Path Lpctmodis MODIS Cloud Top Pressure Lreffclimodis MODIS Ice Cloud Particle Size Lreffclwmodis MODIS Liquid Cloud Particle Size Ltauilogmodis MODIS Ice Cloud Optical Thickness Log10 Mean Ltauimodis MODIS Ice Cloud Optical Thickness Ltautlogmodis MODIS Total Cloud Optical Thickness Log10 Mean Ltautmodis MODIS Total Cloud Optical Thickness Ltauwlogmodis MODIS Liquid Cloud Optical Thickness Log10 Mean Ltauwmodis MODIS Liquid Cloud Optical Thickness Flags for RTTOV outputs Ltbrttov Mean clear sky brightness temperature as calculated by RTTOV 3 Microphysical settings This section discusses how to set up the COSP microphysical settings This is is particularly important for the computation of the radar reflectivities as they are strongly dependent on the paricle size This section should be read in conjunction with Section 4 ofthe QuickBeam User s Guide In the following discussion let s assume that the particle size distribution PSD n D for a particle of diameter D is defined as a gamma function Nz D nor D e XD 1 where no is the interce
4. K M Xu and R Hemler Overlap assumptions for assumed probability distribution function cloud schemes in large scale models J Geophys Res 110 D15S09 doi doi 10 1029 2004JD005100 2005 Saunders R M Matricardi and P Brunel An improved fast radiative transfer model for assim ilation of satellite radiance observations Q J R Meteorol Soc 125 1407 1425 1999 Webb M C Senior S Bony and J J Morcrette Combining ERBE and ISCCP data to assess clouds in the Hadley Centre ECMWF and LMD atmospheric climate models Clim Dyn 17 905 922 2001 Zhang Y S A Klein J Boyle and G G Mace Evaluation of tropical cloud and pre cipitation statistics of CAM3 using CloudSat and CALIPSO data J Geophys Res doi 10 1029 2009JD012006 2010 23
5. e 30f height_half units m T_abs level point T_abs long_name air_temperature T_abs _FillValue 1 e 30f T_abs units K qv level point qv long_name specific_humidity qv _FillValue 1 e 30f 15 float float float float float float float float float float float qv units kg kg rh level point rh long_name relative_humidity_liquid_water rh _FillValue 1 e 30f rh units 4 pfull level point pfull long_name p_in_full_levels pfull _FillValue 1 e 30f pfull units Pa phalf level point phalf long_name p_in_half_levels phalf _FillValue 1 e 30f phalf units Pa mr_lsliq level point mr_lsliq long_name mixing_ratio_large_scale_cloud_liquid mr_lsliq _FillValue 1 e 30f mr_lsliq units kg kg mr_lsice level point mr_lsice long_name mixing_ratio_large_scale_cloud_ice mr_lsice _FillValue 1 e 30f mr_lsice units kg kg mr_ccliq level point mr_ccliq long_name mixing_ratio_convective_cloud_liquid mr_ccliq _FillValue 1 e 30f mr_ccliq units kg kg mr_ccice level point mr_ccice long_name mixing_ratio_convective_cloud_ice mr_ccice _FillValue 1 e 30f mr_ccice units kg kg fl_lsrain level point fl_lsrain long_name flux_large_scale_cloud_rain fl_lsrain _FillValue 1 e 30f fl_lsrain units kg m 2 s 1 fl_lssnow level point fl_lssnow long_name
6. for the CFMIP 2 experi ments These files are also available on the CFMIP web site There are two different configu rations e Long time series long_inline txt This is the configuration for the 30 yr monthly and daily means from ISCCP and CALIPSO PARASOL These are global gridded data computed from model gridded inputs with the simulators run inline The production version for these experiments is COSP v1 3 Experiments already run with v1 2 2 should be fine as long as the outputs look ok COSP v1 3 includes a bug fix in the ISCCP simulator that may cause problem in some circumstances e Short time series short_offline txt This is the configuration for the 1 yr time series both for the curtain outputs and global gridded monthly means from curtain outputs Out puts from CloudSat and CALIPSO PARASOL are requested Version 1 3 can be used as production version for these experiments although the outputs will need some post processing to make them compliant with the final data structure requested by CMIP5 Version 1 3 1 produces data in CMIP5 compliant mode Its been tested with the MIP table CMIP5_cf3hr released on 30 November 2010 and only a minor modification in the values and bounds of the axis scatratio is needed This should be fixed in later tables 5 Using your own cloud generator Currently COSP only includes treatment for cloud precipitation overlap but not subgrid vari ability Please see Section 6 5 of the README txt file
7. if you require this extra capability 6 Processing multiple time steps Processing multiple time steps with versions previous to v1 3 1 was not straight forward Some modifications have been introduced in v1 3 1 to make this easier The COSP_INPUT name list now includes a new variable DINPUT which is the directory where the input files are located FINPUT can now contain a list of input files up to a maximum number of N MAX_INPUT_FILES 12 This is currently set at 1000 in cosp_test but it can be made bigger with no performance effects A value of 10000 has been tested How the time is handled is still not ideal as you have to make sure that the list of files that you pass in FINPUT is complete i e there is no missing step Future versions may include a time variable in the input file that will be used instead You may need to change a couple of things in cosp_test to adapt the program to your time step e Line time_step 3 D0 24 D0 This is the time step in days Currently set for 3 hourly time series e Line time 8 1 D0 8 D0 First time step This defines the time of the first time step The replace append logic worked with CMOR1 but it does not work with CMOR2 This is because of the file naming convention in CMIP5 includes the time limits and this is handled by CMOR2 The file name changes when you add a new time step and therefore it always opens a new file In order to make it work would have to change substa
8. ratio of N2O CO Mixing ratio of CO 2 2 CMOR namelist The CMOR2 library is used to write the ouputs to NetCDF files that comply with the CF Meta data Convention and fulfill the requirements of the climate community s standard model exper iments for CMIP5 The namelist CMOR is used to passed all the metadata that the calls to the CMOR library require This namelist is located in file cmor cosp_cmor_n1 txt and Table 2 details its variables It is expected that this namelist will be expanded in COSPv1 3 to include all the attributes that are required by the CMIP5 Table 2 CMOR namelist INPATH OUTPATH START _ DATE MODEL_ID EXPERIMENT_ID INSTITUTION SOURCE CALENDAR REALIZATION CONTACT HISTORY COMMENT REFERENCES Directory where the MIP table is located Directory where the outputs will be written Experiment start date String with your model name or id Type of experiment This has to be one of those listed in the variable expt_id_ok in the MIP table Your institution Data source e g model version id of your model run Calendar type used by the model Realisation within an ensemble of runs for a given experi ment Contact details What CMOR has done to the user supplied data e g transforming its units or rearranging its order to be consis tent with the MIP requirements You can live this blank Extra comments that may help the interpretation of the data Papers or other references describing
9. COSP user s manual Version 1 3 1 A Bodas Salcedo Met Office Hadley Centre FitzRoy Rd Exeter EX1 3PB United Kingdom December 22 2010 British Crown Copyright 2010 Contents 1 Introduction 1 2 Configuration setting the COSP namelists 2 21 GCGOSP INPUT AMIENS tasse Sal Caine asd ad Sache idee he he oa Ee Hak Te a EE Ge 3 22 1OMORTAMOlSE ER carb de dl te ld gre cates Bas Pearcy cade ca toe Re eee be 5 2 3 COSP OUTPUT namelist i lt eae Si aay dans ee D Oe we aR BERR EMS 6 3 Microphysical settings 8 3 1 Effective radius 2 4 a eae ARE AAAS BE RA GA BAAS 8 3 2 Mixing ratios from precipitation fluxes 9 3 3 Setting the microphysical constants 10 3 4 S ttingthe ACLASS table acs es ob Bis oy Eo ara dant we aE Re at 11 4 Configuration for CFMIP 2 experiments 12 5 Using your own cloud generator 12 6 Processing multiple time steps 12 1 Introduction The Cloud Feedback Model Intercomparison Project CFMIP Observation Simulator Package COSP is a modular piece of software whose main aim is to enable the simulation of data from several satellite borne sensors from model variables It is written almost entirely in Fortran 90 and it is conceptually divided into three steps First the gridbox mean profiles are broken into subcolumns Then the vertical profiles of individual subcolumns are passed to individual instrument simulators e g lidar forward model ISCCP si
10. ameter I_LSRAIN integer parameter I_LSSNOW Il nF WYN e integer parameter I_CVCLIQ 10 integer parameter I_CVCICE integer parameter I_CVRAIN integer parameter I_CVSNOW ON OD integer parameter I_LSGRPL 3 4 Setting the HCLASS table The microphysical assumptions for the radar simulation in COSP are stored in the HCLASS table in cosp_constants F90 The meaning of the HCLASS constants are given in the Quick beam Users guide Haynes 2007 For the sake of completeness here we also give an overview and the settings The HCLASS table consists of several lines each one stored in a different variable These variables are vectors with as many elements as number of hydrom eteors so that the settings for each hydrometeor can be set up independently These variables are HCLASS_TYPE Set to 1 for modified gamma distribution 2 for exponential distribution 3 for power law distribution 4 for monodisperse distribution 5 for lognormal distribution Set to a negative number to ignore the hydrometeor class defined in that position HCLASS_COL Reserved for future use value is ignored HCLASS_PHASE Set to 0 for liquid 1 for ice HCLASS CP Not used in COSP HCLASS_DMIN The minimum drop size for this class um ignored for monodisperse HCLASS_DMAX The maximum drop size for this class um ignored for monodisperse HCLASS_APM The a coefficient in in the mass diameter relationship If used then s
11. blank if you are using the full path in FINPUT List input NetCDF files Input file with all the input variables to that your COSP executable will read and process Inputs related to radar simulations RADAR_FREQ SURFACE_RADAR use_mie_tables Frequency GHz used in the radar simulations Radar position surface 1 spaceborne 0 Use a precomputed lookup table yes 1 no 0 use_gas_abs Include gaseous absorption yes 1 no 0 do_ray Calculate output Rayleigh refl 1 not 0 This should be set to 0 as the Rayleigh reflectivity is not output by COSP melt_lay Melting layer model off 0 on 1 k2 use _reff use _ precipitation fluxes Dielectric factor of water 1 use frequency dependent default True if you want effective radius to be used by radar simu lator always used by lidar true True if precipitation fluxes are input to the algorithm Inputs related to lidar simulations Nprmts_max_hydro Naero Nprmts_max_aero lidar_ice_type OVERLAP Max number of parameters for hydrometeor size distribu tions Number of aerosol species Not used Max number of parameters for aerosol size distributions Not used Ice particle shape in lidar calculations 0 ice spheres 1 ice non spherical Overlap type 1 max 2 rand 3 max rand Inputs related to ISCCP simulations ISCCP_TOPHEIGHT 1 adjust top height using both a computed infrared bright ness temperature and t
12. cice units kg kg mr_ccice long_name mixing_ratio_convective_cloud_ice mr_ccice FillValue 1 e 30f float fl_lsrain level lat lon fl_lsrain units kg m 2 s 1 fl_lsrain long_name flux_large_scale_cloud_rain fl_lsrain FillValue 1 e 30f float fl_lssnow level lat lon fl_lssnow units kg m 2 s 1 fl_lssnow long_name flux_large_scale_cloud_snow fl_lssnow FillValue 1 e 30f float fl_lsgrpl level lat lon fl_lsgrpl units kg m 2 s 1 fl_lsgrpl long_name flux_large_scale_cloud_graupel fl_lsgrpl FillValue 1 e 30f float fl_ccrain level lat lon fl_ccrain units kg m 2 s 1 fl_ccrain long_name flux_convective_cloud_rain fl_ccrain FillValue 1 e 30f float fl_ccsnow level lat lon fl_ccsnow units kg m 2 s 1 fl_ccsnow long_name flux_convective_cloud_snow fl_ccsnow FillValue 1 e 30f float orography lat lon orography units m orography long_name orography orography FillValue 1 e 30f float landmask lat lon landmask units i landmask long_name land_mask landmask FillValue 1 e 30f float height_half level lat lon height_half units m height_half long_name height_in_half_levels height_half FillValue 1 e 30f float psfc lat lon 20 psfc units Pa psfc long_name surface_pressure psfc FillValue 1 e 30f float Reff hydro level lat lon Reff unit
13. day day _FillValue 127b day units day byte hour point hour long_name hour hour _FillValue 127b hour units hr byte minute point minute long_name minute minute _FillValue 127b minute units min float second point second long_name second second _FillValue 1 e 30f second units s float t point t long_name t t _FillValue 1 e 30f t units min float tUM point 14 float float float float float float float float float float tUM long_name tUM tUM FillValue 1 e 30f tUM units min lst point lst long_name lst lst _FillValue 1 e 30f lst units h lon point lon long_name longitude lon _FillValue 1 e 30f lon units degree_east lat point lat long_name latitude lat _FillValue 1 e 30f lat units degree_north landmask point landmask long_name landmask landmask _FillValue 1 e 30f landmask units 1 orography point orography long_name orography orography _FillValue 1 e 30f orography units m psfc point psfc long_name surface_pressure psfc _FillValue 1 e 30f psfc units Pa height level point height long_name height_in_full_levels height _FillValue 1 e 30f height units m height_half level point height_half long_name height_in_half_levels height_half _FillValue 1
14. et HCLASS_RHO to 1 HCLASS_BPM The b coefficient in in the mass diameter relationship If used then set HCLASS_RHO to 1 HCLASS_RHO hydrometeor density kgm If used then set HCLASS_APM and HCLASS_BPM to 1 e HCLASS_P1 HCLASS_P2 HCLASS_P3 these parameters depend on the type of dis tribution For the modified gamma distribution used in the UM P1 is the total particle number concentration P2 is the particle mean diameter um and P3 is the distribution width a 1 One of the parameters P1 P2 must be specified and the other one should be set to 1 P3 must be specified The settings for DMIN and DMAX are ignored in the current version for all distributions except for power law Except when the power law distribution is used particle size is fixed to vary from zero to infinity 11 Since COSP v0 2 a capability of Quickbeam to pass the effective radius as input parameter is used In that case the settings in HCLASS_P 1 3 are defaults If the input Resp is zero at any spatial or hydrometeor coordinate at which there is condensate then the HCALSS default is used Hence if the effective radius is not zero when there is hydrometeor present the values in HCLASS P2 are not used The default values in the COSP HCLASS table reflect those used by Roj Marchand to run the simulator for the MMF Marchand et al 2009 4 Configuration for CFMIP 2 experiments The directory cfmip2 contains the namelists with the configuration
15. he visible optical depth to adjust cloud top pressure Note that this calculation is most ap propriate to compare to ISCCP data during sunlit hours 2 do not adjust top height that is cloud top pres sure is the actual cloud top pressure in the model 3 adjust top height using only the computed infrared brightness temperature Note that this calculation is most appropriate to compare to ISCCP IR only algortihm i e you can compare to nighttime ISCCP data with this option ISCCP_TOPHEIGHT_DIRECTIONdirection for finding atmosphere pressure level with interpolated temperature equal to the radiance determined cloud top temperature 1 find the lowest altitude highest pres sure level with interpolated temperature equal to the radiance determined cloud top temperature 2 find the highest altitude lowest pressure level with interpolated temperature equal to the radiance de termined cloud top temperature This is the default value since V4 0 of the ISCCP simulator ONLY APPLICABLE IF top_height EQUALS 1 or 3 Inputs related to RTTOV simulations Platform Satellite Instrument Nchannels Satellite platform number Satellite Instrument Number of channels to be computed Channels Channel numbers please be sure that you supply Nchan nels Surfem Surface emissivity please be sure that you supply Nchan nels ZenAng Satellite Zenith Angle degrees CO2 Mixing ratio of CO CH4 Mixing ratio of CH4 N20 Mixing
16. lue recorded in variable time Flags for ISCCP simulator outputs Lalbisccp ISSCP Mean Cloud Albedo Lboxptopisccp Cloud Top Pressure in Each Column as Calculated by the ISCCP Simulator Lboxtauisccp Optical Depth in Each Column as Calculated by the ISCCP Simulator Lclisccp ISSCP Cloud Area Fraction 6 Lcltisccp ISSCP Total Cloud Fraction Lmeantbclrisccp Mean clear sky 10 5 micron brightness temperature as cal culated by the ISCCP Simulator Lmeantbisccp Mean all sky 10 5 micron brightness temperature as calcu lated by the ISCCP Simulator Ltauisccp Mean Optical Depth as Calculated by the ISCCP Simulator Lpctisccp ISSCP Mean Cloud Top Pressure Flags for CALIPSO simulator outputs Latb532 Lidar Attenuated Total Backscatter 532 nm LcfadLidarsr532 CALIPSO Scattering Ratio CFAD Lclcalipso2 CALIPSO Cloud Fraction Undetected by CloudSat Lclcalipso CALIPSO Cloud Area Fraction Lclhcalipso CALIPSO High Level Cloud Fraction Lcllcalipso CALIPSO Low Level Cloud Fraction Lclmcalipso CALIPSO Mid Level Cloud Fraction Lcltcalipso CALIPSO Total Cloud Fraction LparasolRefl PARASOL Reflectance LlidarBetaMol532 Lidar Molecular Backscatter 532 nm Flags for CloudSat simulator outputs Lcfaddbze94 CloudSat Radar Reflectivity CFAD Ldbze94 CloudSat Radar Reflectivity Flags for CALIPSO CloudSat combined outputs Lcltlidarradar Lidar and Radar Total Cloud Fraction Flags for other outputs Lfracout Subcolumn output from SCOPS
17. milator Finally a statistical module gathers the outputs from all the instruments and builds statistics that can be compared to similar statistics from observations The scheme that we use to break the grid box mean profiles of cloud water contents is the Subgrid Cloud Overlap Profile Sampler SCOPS a technique developed for the International Satellite Cloud Climatology Project ISCCP simulator Klein and Jakob 1999 Webb et al 2001 SCOPS uses a pseudo random sampling process fully consistent with the maximum random and maximum random cloud overlap assumptions used in many models e g Pincus et al 2005 Maximum overlap is applied to the convective cloud and maximum random is used for large scale cloud Zhang et al 2010 have developed a simple algorithm that pro vides sub grid distribution of precipitation fluxes compatible with the cloud distribution output by SCOPS and the gridbox mean precipitation fluxes simulated by the model The current version of COSP includes simulators for the following instruments CloudSat radar Haynes et al 2007 CALIPSO lidar Chepfer et al 2008 ISCCP Klein and Jakob 1999 Webb et al 2001 the Multiangle Imaging SpectroRadiometer MISR and the Moder ate Resolution Imaging Spectroradiometer MODIS The fast radiative transfer code RTTOV Saunders et al 1999 can also be linked to COSP to produce clear sky brightness tempera tures for many different channels of past and current infrared a
18. nd passive microwave radiome ters The Climate Model Output Rewriter CMOR library is used to write the ouputs to NetCDF files that comply with the Climate and Forecast CF Metadata Convention and fulfill the require ments of the climate community s standard model experiments The Coupled Model Intercom parison Project Phase 5 CMIP5 has requested COSP outputs to be included into a subset of CMIP5 experiments COSP is open source software and can be downloaded from the CFMIP website without charge A description paper has been submitted to BAMS Bodas Salcedo et al submitted The document is organised as follows Section 2 provides information on the namelists that are used to configure COSP Section 3 discusses how to set up the microphysical settings Section 4 gives some details on the configuration of COSP for CFMIP 2 experiments Appendix A shows the structure of the NetCDF input data files This document is still under development and therefore is not complete although hope it will still be useful in its current form It is encouraged to read the README txt file that is included with COSP along with this user s manual 2 Configuration setting the COSP namelists The user interaction with COSP is done via namelists This section provides information on the namelists that are used to configure COSP Thttp cmip pemdi linl gov emip5 experiment_design html 2http Avww cfmip net 2 1 COSP INPUT namelist This namelist is l
19. nds lat bnds float height level lat lon height units m height long_name height_in_full_levels height FillValue 1 e 30f float pfull level lat lon pfull units Pa pfull long_ name p_in_full_levels pfull FillValue 1 e 30f float phalf level lat lon phalf units Pa phalf long_ name p_in_half_levels phalf FillValue 1 e 30f float T_abs level lat lon T_abs units K T_abs long_name air_temperature T_abs FillValue 1 e 30f float qv level lat lon qv units kg kg qv long_name specific_humidity qv FillValue 1 e 30f float rh level lat lon rh units rh long_name relative_humidity rh FillValue 1 e 30f float tca level lat lon tca units 1 tca long_name total_cloud_amount tca FillValue 1 e 30f float cca level lat lon cca units 1 cca long_name convective_cloud_amount cca FillValue 1 e 30f float mr_lsliq level lat lon mr_lsliq units kg kg mr_lsliq long_name mixing_ratio_large_scale_cloud_liquid mr_lsliq FillValue 1 e 30f float mr_lsice level lat lon mr_lsice units kg kg mr_lsice long_name mixing_ratio_large_scale_cloud_ice 19 mr_lsice FillValue 1 e 30f float mr_ccliq level lat lon mr_ccliq units kg kg mr_ccliq long_name mixing_ratio_convective_cloud_liquid mr_ccliq FillValue 1 e 30f float mr_ccice level lat lon mr_c
20. northward_wind v_wind FillValue 1 e 30f 22 References Bodas Salcedo A et al COSP satellite simulation software for model assessment Bull Am Meteorol Soc submitted Chepfer H S Bony D Winker M Chiriaco J L Dufresne and G S ze Use of CALIPSO lidar observations to evaluate the cloudiness simulated by a climate model Geophys Res Lett 35 L15 704 doi 10 1029 2008GL034207 2008 Haynes J M QuickBeam radar simulation software Colorado State University Fort Collins CO USA v1 1 ed 2007 Haynes J M R T Marchand Z Luo A Bodas Salcedo and G L Stephens A multi purpose radar simulation package Quickbeam Bull Am Meteorol Soc 88 11 1723 1727 doi 10 1175 BAMS 88 11 1723 2007 Khairoutdinov M F and D A Randall Cloud resolving modeling of the ARM summer 1997 IOP Model formulation results uncertainties and sensitivities J Atmos Sci 60 4 607 625 doi 10 1175 1520 0469 2003 060 0607 CRMOTA 2 0 CO 2 2003 Klein S A and C Jakob Validation and sensitivities of frontal clouds simulated by the ECMWF model Mon Weather Rev 127 10 2514 2531 1999 Marchand R J Haynes G G Mace T Ackerman and G Stephens A comparison of simulated cloud radar output from the multiscale modeling framework global climate model with CloudSat cloud radar observations J Geophys Res 114 DOOA20 doi 10 1029 2008JD009790 2009 Pincus R C Hannay S A Klein
21. ntially the COSP output routines Therefore this will create one output file per time step If you are outputting a long time series of several variables then the number of files can be large and it is convenient to merge the outputs in one file per variable The script utils append_cf3hr_files sh uses the NetCDF Operators to merge the files and create one file per variable Acknowledgements COSP is a collaborative effort and many people have been involved in the development of the software Thanks to M J Webb S Bony H Chepfer J L Dufresne S A Klein Y Zhang R Marchand J M Haynes R Pincus and V O John http nco sourceforge net nco html 13 Appendix A Structure of the NetCDF input data files The structure of the input data NetCDF files are listed below Examples of these files are distributed with COSP namely cosp_input_um nc for 1D mode and cosp_input_um_2d nc for 2D mode The 1D mode represents data along a trajectory like the orbit track The 2D mode is a gridded lat lon input suitable for model outputs This is the Common Data Language CDL structure of the COSP input NetCDF file in 1D mode netcdf cosp_input_um dimensions point 1236 level 50 hydro 9 variables short year point year long_name year year _FillValue 32767s year units yr byte month point month long_name month month _FillValue 127b byte day point day long_name
22. ocated in file cosp_input_nl txt and it contains the input arguments for COSP and all the simulators Table 1 contains a description of the variables in this namelist For details on RTTOV variables please refer to RTTOV documentation Table 1 COSP_INPUT namelist General configuration variables CMOR_NL NPOINTS NPOINTS_IT NCOLUMNS NLEVELS USE_VGRID NLR CSAT_VGRID DINPUT FINPUT Name of CMOR namelist Section 2 2 Number of gridpoints to be processed This has to coincide with the number of points of the NetCDF input file in 2D mode lat lon For 1D curtain mode there is no restric tion Maximum number of gridpoints to be processed in one iter ation This helps to reduce the amount of memory used by COSP If you find memory faults reduce this number Number of subcolumns used for each profile Number of levels This must be the same number as in the input NetCDF file If false the outputs are written on model levels If this is set to true then a vertical grid evenly spaced in altitude is used If true then you need to define number of levels with Nir Number of levels in statistical outputs only used if USE_VGRID true Set to true for CloudSat vertical grid This is just a stan dard grid of 40 levels evenly spaced at CloudSat vertical resolution 480 m This only applies if USE_VGRID true Directory where the input files are located Useful when processing multiple files Leave
23. pt parameter is the slope parameter a is the constant shape parameter x can be either R for rain a for aggregates c for ice crystals or g for graupel For a single moment scheme the intercept parameter is assumed constant or a simple function of Ax ee r A 2 where naz and np are constants The terminal fall velocity of a precipitating particle Vz D can be expressed as a function of diameter V D c D 2 3 where cr dz hy and Gz are constants p is the air density kg m and po is a reference density of 1 29 We assume a power law relating the mass of the particle to the diameter M D az D 4 The mass diameter relation for rain simply assumes a spherical drop with a density equal to that for liquid water 1000 kg m 3 1 Effective radius COSP requires effective radius as input for CALIPSO and CloudSat Default values can be used although it is recommended to use values that are consistent with the model s micro physics You can use the default values by setting to zero the input array of effective radii The defaults are 30 um for the lidar and the values defined in HCLASS_P1 for CloudSat see Shttp reef atmos colostate edu haynes radarsim userguide pdf 8 details below In order to compute the effective radius it is necessary to be able to infer the particle size distribution This requires to being able to obtain the parameter Az from the model variables specific humidities or precipita
24. s m Reff long_name hydrometeor_effective_radius Reff FillValue 1 e 30f float dtau_s level lat lon dtau_s units 4 dtau_s long_name Optical depth of stratiform cloud at 0 67 micron dtau_s FillValue 1 e 30f float dtau_c level lat lon dtau_c units 4 dtau_c long_name Optical depth of convective cloud at 0 67 micro dtau_c FillValue 1 e 30f float dem_s level lat lon dem_s units 1 dem_s long_name Longwave emissivity of stratiform cloud at 10 5 micron dem_s FillValue 1 e 30f float dem_c level lat lon dem_c units 1 dem_c long_name Longwave emissivity of convective cloud at 10 5 micron dem_c FillValue 1 e 30f float skt lat lon skt units skt long_name K Skin temperature skt FillValue 1 e 30f float sunlit lat lon sunlit units 1 sunlit long_ name Day points sunlit FillValue 1 e 30f float emsfc_lw emsfc_lw unit emsfc_lw long emsfc_lw Fill float mr_ozone le gs 1 _name Surface emissivity at 10 5 micron fraction Value 1 e 30f vel lat lon mr_ozone units kg kg mr_ozone long_name mass_fraction_of_ozone_in_air mr_ozone FillValue 1 e 30f float u_wind lat lon u_Wind units m s 1 u_wind long_name eastward_wind 21 u_wind FillValue 1 e 30f float v_wind lat lon v_wind units m s 1 v_wind long_name
25. s available since COSP v1 3 The conversion is done by the subroutine cosp_precip_mxratio which generalises the previous subroutine pf_to_mr that was only compatible with the method from Khairoutdinov and Randall 2003 The microphys ical constants needed for the precipitation are stored in cosp_constants F90 along with the HCLASS table used for the reflectivity computations see below These two sets of constants have to be filled carefully with consistent constants Table 4 lists the correspondence between FORTRAN names stored in cosp_constants F90 and the constants in used in this document FORTRAN name COSP manual N_ax Nax N_bx Nox alpha_x Qx c_x Cx d_x dy 8 X 9x a_x Qe b_x by gamma_1 ri gamma_2 lo gamma_3 Ts gamma_4 Ta Table 4 Correspondence between the FORTRAN names used in COSP and the formulation in used in this document These values are defined in data statements in cosp constants F90 If the formulation presented here is not compatible with your models formulation then you will have to set use_precipitation_fluxes false do the conversion off line following your model s fomulation and fill in the arrays gbx mr_hydro i with the precipitation mixing ratios in cosp_test i is the index of each precipitation class _LSRAIN I LSSNOW I_CVRAIN CVSNOW I_LSGRPL The standard list of hydrometeors is defined in cosp_constants F90 integer parameter I_LSCLIQ integer parameter I_LSCICE integer par
26. the model TABLE Name of the MIP table This has to be consistent with the mode used to run COSP which is defined by the input file Different tables are needed for 1D and 2D models The current list of table distributed with COSP are COSP table 1D MIP table for 1D mode This is a modified version with extra variables of the CMIP5Scf3hr distributed with the CMOR2 library for the off line CFMIP2 experiments COSP table 1D cmori the same as COSP table 1D but to be used when linking COSP with CMOR1 3 COSP table 2D table to be used in 2D mode COSP table 2D cmori same as COSP table 2D but to be used when linking COSP with CMOR1 3 MAXTSTEPS Maximum number of records that can be recorded to the output files CMOR will issue an error and stop if you try to write more records 2 3 COSP OUTPUT namelist This is the namelist that sets up output related variables see Table 3 It controls the instrument simulators that are run and the list of variables to be written to file If a simulator is switched off then none of its outputs are written out independently of the status of the logical flags of the output variables associated with that particular simulator Table 3 COSP_OUTPUT namelist Logical flags that control which simulators are run Lradar_sim Llidar_sim Lisccp_sim Lmisr_sim Lmodis_sim Lrttov_sim Variables only in 1D curtain mode Ltoffset Time difference days between the time of each profile and the va
27. tion fluxes The ith moment of the PSD is given by i ro ax i 1 When the hydrometeor mixing ratio is available the value of A is given by Ae rte LS Dre Px For precipitation fluxes the flux can be related to the PSD by nS f MD Dne D dD 7 0 Using Eqs 1 2 4 and solving this integral for A gives ut Ga aada ls TT Qz Cr 2 Nar Az bz dx 1 Tiaria tI x T 8 x The effective radius is then given by 2u2 Ilar 3 7 3 2 Mixing ratios from precipitation fluxes The radar reflectivities are computed from the hydormeteor mixing ratios However as large scale models typically diagnose precipitation fluxes there exists the possibility of passing pre cipitation fluxes and let COSP convert them into mixing ratios before calling the radar simula tor The variable use_precipitation_fluxes in the COSP_INPUT namelist controls whether the COSP should do this conversion or use the input mixing ratios instead Expanding and integrating Eq 3 1 the expression for the precipitation flux as a function of the mixing ratio and the parameters that define the PSD is given by ee Pres 0 Pr m ao pida p T Tag by 1 Nazar Az by 1 Solving for the mixing ratio gives 1 p Ga 1 Po where E ota Qx 0x Nbx 1 Az by dz 1 Oz bz 1 ax 3 ax 4 F NardzI 2 3 3 Setting the microphysical constants The formulation presented here i
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