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aerocom:indirect [2013-10-01 19:37:26]
steve.ghan@pnnl.gov
aerocom:indirect [2022-05-31 09:29:31]
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-===== Indirect Effect Experiment Remarks ===== 
- 
-==== Indirect forcing experiment ===== 
- 
-====== 
- 
-== Data submission deadline == 
- 
-   Submission of results by 1 December 2013  
- 
-== Simulation setup == 
- 
-   Simulation start 1 October 2005 \\   
-   Forcing by AMIP2 sea surface temperature and sea-ice extent \\  
-   Preferred: Nudge toward ECMWF reanalysis winds (not temperature) through 2010 \\ 
-   Acceptable: Nudge toward winds from one baseline simulation by your model \\ 
-   Less acceptable: No nudging \\  
-   Greenhouse gas concentrations for year 2000 \\  
-   Aerosol direct, semi-direct, and indirect effects taken into account.  \\  
- 
-   all_2000: simulation PD (present-day): year 2000 IPCC aerosol emissions \\  
-   all_1850: simulation PI (pre-industrial): year 1850 IPCC aerosol emissions (year 2000 GHG concentration)  \\  
-   hom_2000: present day emissions no heterogeneous nucleation of ice \\ 
-   hom_1850: pre-industrial emissions no heterogeneous nucleation of ice \\ 
-   fix_2000: present day emissions fixed ice nucleation for T%%<%%-37 C using Cooper (1986) as a f(temperature) \\ 
-   fix_1850: pre-industrial emissions fixed ice nucleation for T%%<%%-37 C using Cooper (1986) as f(temperature) \\ 
- 
- 
-     
-=== Diagnostics === 
- 
-   All data except COSP diagnostics is to be collected at the AEROCOM server. \\  
-   Groups hold COSP diagnostics until analyst is identified \\ 
-   follow the aerocom data protocol (http://aerocom.met.no/protocol.html) \\  
-   Data in NetCDF format, one variable and year per file with CMOR variable names \\  
-   All data are 3-dimensional ( lon x lat x time )  \\  
-   filenames aerocom_<ModelName>_<ExperimentName>_<VariableName>_<VerticalCoordinateType>_<Period>_<Frequency>.nc \\ 
-    where <ModelName> can be chosen such that Model Name, Model version and possibly the institution can be identified. No underscores (_) are allowed in <ModelName>. Use (-) instead. Max 20 characters.  
-    <ExperimentName> = all_2000, all_1850, hom_2000, hom_1850, fix_2000, or fix_1850  
-    <VariableName> see list below  
-    <VerticalCoordinateType> => "Surface", "Column", "ModelLevel"  
-    <Period> => "2008", "2010", ...   
-    <Frequency> => "timeinvariant","hourly", ,"3hourly", "daily", "monthly"  
- 
-  CFMIP COSP diagnostics provided by COSP do not need to be run through cmor because the names are the same, \\ 
-     but please separate files for each variable 
- 
-    In addition to the diagnostics below, it is highly recommended to store the AEROCOM standard and forcing diagnostics,  
-    so that the simulations can be analysed for the direct forcing as well, and future more in-depth analyses are possible.  
- 
-(1) 2D diagnostics for evaluation with satellite data 
- 
-5 years (years 2006-2010) of 3-hourly data from the PD run 
-====== 
-^ name ^ long_name (CF if possible) ^ units ^ description ^ 
-| od550aer  | atmosphere_optical_thickness_due_to_aerosol | 1 | Aerosol optical depth (@ 550 nm) | 
-| angstrm |  AOD_Angstrom_exponent | 1 | | 
-| aerindex |aerosol_index  | 1  | AOD*angstrm 
-| cdr | liquid_cloud-top_droplet_effective_radius | m  | Grid cell mean droplet effective radius at top of liquid water clouds | 
-| cdnc | liquid_cloud_droplet_number_concentration | m-3 | Grid cell mean droplet number concentration in top layer of liquid water clouds | 
-| cdnum  | column_cloud_droplet_number_concentration    |   m-2  |   grid cell mean column total | 
-| icnum  | column_ice_crystal_number_concentration    |   m-2  |   grid cell mean column total | 
-| clt | cloud_area_fraction | 1 | Fractional cover by all clouds | 
-| lcc | liquid_cloud_area_fraction  | 1 | Fractional cover by liquid water clouds | 
-| lwp | atmosphere_cloud_ice_content | kg m-2 | grid cell mean liquid water path for liquid water clouds | 
-| iwp  | atmosphere_cloud_ice_content | kg m-2 | grid cell mean ice water path for ice clouds | 
-| icr | cloud-top_ice_crystal_effective_radius | m | grid cell mean effective radius of crystals at top of ice clouds | 
-| icc | ice_cloud_area_fraction | 1  | Fractional cover by ice clouds | 
-| cod | atmosphere_optical_thickness_due_to_clouds | 1 | Grid cell mean cloud optical depth | 
-| codliq | atmosphere_optical_thickness_due_to_liquid_clouds | 1 | Grid cell mean cloud optical depth | 
-| codice | atmosphere_optical_thickness_due_to_ice_clouds | 1 | Grid cell mean cloud optical depth | 
-| ccn0.1bl | cloud_condensation_nuclei_0.1_pbl | m-3 | grid-cell mean CCN number concentration at S=0.1% at 1 km above the surface | 
-| ccn0.3bl | cloud_condensation_nuclei_0.3_pbl | m-3 | grid-cell mean CCN number concentration at S=0.3% at 1 km above the surface | 
-| colccn.1 | column_cloud_condensation_nuclei_0.1 | m-2 | grid-cell mean column-integrated CCN number concentration at S=0.1%  | 
-| colccn.3 | column_cloud_condensation_nuclei_0.3 | m-2 | grid-cell mean column-integrated CCN number concentration at S=0.3%  | 
-| rsut | toa_upward_shortwave_flux | W m-2 | TOA upward SW flux, all-sky | 
-| rsutcs | toa_upward_shortwave_flux_assuming_clear_sky | W m-2 | TOA upward SW flux, clear-sky | 
-| rsutnoa | toa_upward_shortwave_flux_no_aerosol | W m-2 | TOA upward SW flux, all-sky, aerosol removed from calculation | 
-| rsutcsnoa | toa_upward_shortwave_flux_clear_sky_no_aerosol |W m-2 | TOA upward SW flux, clear-sky, aerosol removed from calculation | 
-| rlut | toa_upward_longwave_flux | W m-2 | TOA upward LW flux, all-sky | 
-| rlutcs | toa_upward_longwave_flux_assuming_clear_sky | W m-2 | TOA upward LW flux, clear-sky | 
-| hfls | surface_upward_latent_heat_flux | W m-2 | Surface latent heat flux | 
-| hfss | surface_upward_sensible_heat_flux  | W m-2 | Surface sensible heat flux | 
-| rls | surface_net_downward_longwave_flux_in_air | W m-2 | Net surface LW downward flux | 
-| rss | surface_net_downward_shortwave_flux | W m-2 | Net surface SW downward flux | 
-| rsds | surface_downwelling_shortwave_flux_in_air | W m-2 | Surface SW downward flux (in order to estimate the model's 'true' surface albedo) | 
-| ttop | air_temperature_at_cloud_top | K | Temperature at top of clouds | 
-| lts | lower_tropospheric_stability | K | Difference in potential temperature between 700 hPa and 1000 hPa | 
-| w500  |  vertical_velocity_dpdt_at_500_hPa | hPa s-1 | | 
-| sprecip | stratiform_precipitation_rate |kg m-2 s-1 | grid cell mean at surface | 
-| autoconv | column_autoconversion_rate | kg m-2 s-1 | grid cell mean column total | 
-| accretn | column_accretion_rate | kg m-2 s-1 | grid cell mean column total | 
- 
-===== 
- 
-(2) For forcing estimates: as in (1), but monthly-mean fields for both PD and PI simulations 
- 
-(3) 3D monthly mean diagnostics 
- 
-^ name ^ long_name (CF if possible) ^ units ^ description ^ 
-| t | temperature | K | |  
-| hus | specific_humidity | kg/kg ||  
-| ccn0.1 | cloud_condensation_nuclei_0.1 | m-3 | grid cell mean each layer (S=0.1%) | 
-| ccn0.3 | cloud_condensation_nuclei_0.3 | m-3 | grid cell mean each layer (S=0.3%) | 
-| nc | liquid_cloud_droplet_number_concentration | m-3 | grid cell mean each layer | 
-| lwc| cloud_liquid_water_content | kg m-3 | grid cell mean each layer | 
-| ewl | droplet_effective_radius  | m| grid cell mean each layer | 
-| lccl | liquid_cloud_fraction | 1 | Fractional cover by liquid water clouds each layer | 
-| wsubc | subgrid_vertical_velocity_for_stratiform | wsubc | m s-1 |  
-| autocl  | autoconversion_rate | kg m-2 s-1 | layer total in grid cell | 
-| accretl  | accretion_rate | kg m-2 s-1 | layer total in grid cell | 
-| ni | ice_cloud_crystal_number_concentration | m-3 | grid cell mean each layer | 
-| iwc | cloud_ice_water_content | kg m-3 | grid cell mean each layer | 
-| rei | Ice_effective_radius | m | grid cell mean each layer | 
-| iccl  | ice_cloud_fraction | 1 | Fractional cover by ice water clouds each layer | 
-| sati  | ice_supersaturation | 1 | Supersaturation with respect to ice | 
-| wsubi  | subgrid_vertical_velocity_for_cirrus | m s-1 |  | 
-| cirrus_nso4  | sulfate_aerosol_number_for_homogeneous | m-3 | grid cell mean sulfate aerosol number used for homogeneous aerosol freezing for T<-37C | 
-| cirrus_ndust  | dust_aerosol_number_for_heterogeneous | m-3 | grid cell mean dust aerosol number used for heterogeneous aerosol freezing for T<-37C | 
-| cirrus_nbc  | BC_aerosol_number_for_heterogeneous | m-3 | grid cell mean BC aerosol number used for heterogeneous aerosol freezing for T<-37C | 
-| cirrus_nihom  | homogeneous_nucleation_number | m-3 | grid cell mean ice crystal number production from homogeneous aerosol freezing for T<-37C during one model time step | 
-| cirrus_nihet  | heterogeneous_nucleation_number | m-3 | grid cell mean ice crystal number production from heterogeneous aerosol freezing for T<-37C during one model time step | 
-| cirrus_freqhom | homogeneous_nucleation_frequency | 1 | frequency counter of homogeneous aerosol freezing for T<-37C. For each time step, freqhom = 1 if homogeneous ice nucleation happens; otherwise freqhom = 0. Monthly average of this value indicates the homogeneous nucleation frequency. | 
-| cirrus_freqhet  | heterogeneous_nucleation_frequency | 1 | frequency counter of heterogeneous aerosol freezing for T<-37C. At each model time step, set freqhom = 1 if heterogeneous ice nucleation happens; otherwise freqhom = 0. Monthly average of this value indicates the heterogeneous nucleation frequency. | 
-| mp_hetnuc  | droplet_freezing_rate_by_heterogeneous | m-3 s-1 | grid cell mean freezing rate of cloud droplets in mixed-phase clouds for T>-37C | 
-| mp_homnuc  | droplet_freezing_rate_by_homogeneous | m-3 s-1 | grid cell mean instantaneous freezing rate of cloud droplets for T<=-37C | 
-===== 
- 
-(4) Optional CFMIP COSP diagnostics. Highly desirable but optional for now \\  
-3-hr snapshots and daily means for 3-month (which?) PD simulation only. 
- 
-^ name ^ long_name (CF if possible) ^ units ^ description ^ comment ^ notes ^ 
-| t | temperature | K |  each layer |  
-| z | altitude          | m       | each layer |  
-| ccn0.1 | cloud_condensation_nuclei_0.1 | m-3 | grid cell mean each layer (S=0.1%) | 
-| ccn0.3 | cloud_condensation_nuclei_0.3 | m-3 | grid cell mean each layer (S=0.3%) | 
-| nc | liquid_cloud_droplet_number_concentration | m-3 | grid cell mean each layer | 
-| lwc| cloud_liquid_water_content | kg m-3 | grid cell mean each layer | 
-| ewl | droplet_effective_radius  | m| grid cell mean each layer | 
-| lccl | liquid_cloud_fraction | 1 | Fractional cover by liquid water clouds each layer | 
-| ni | ice_cloud_crystal_number_concentration | m-3 | grid cell mean each layer | 
-| iwc | cloud_ice_water_content | kg m-3 | grid cell mean each layer | 
-| rei | Ice_effective_radius | m | grid cell mean each layer | 
-| iccl  | ice_cloud_fraction | 1 | Fractional cover by ice water clouds each layer | |  | 
-| radar  | 94GHz_radar_subcolumn | dBZe  | Radar reflectivity in 70 subcolumns   | 
-| fracout | fracout_cloud_flag_subcolumn | 1 | subcolumn cloud flag 0 clear, 1 strat 2 conv | 
-| clcalipso | cloud_area_fraction_in_atmosphere_layer | % | CALIPSO Cloud Area Fraction | | at 40 height levels | 
-| clcalipso2   | cloud_area_fraction_in_atmosphere_layer | % | CALIPSO Cloud Fraction Undetected by CloudSat | Clouds detected by CALIPSO but below the detectability threshold of CloudSat | at 40 height levels | 
-| cfadDbze94 | histogram_of_equivalent_reflectivity_factor_over_height_above_reference_ellipsoid | 1 | CloudSat Radar Reflectivity CFAD | CFADs (Cloud Frequency Altitude Diagrams) are joint height - radar reflectivity  distributions. | 40 levels x 15 bins | 
-| cfadLidarsr532 | histogram_of_backscattering_ratio_over_height_above_reference_ellipsoid | 1 | CALIPSO Scattering Ratio CFAD | CFADs (Cloud Frequency Altitude Diagrams) are joint height - lidar scattering ratio distributions. | 40 levels x 15 bins | 
-| parasolRefl | toa_bidirectional_reflectance | 1 | PARASOL Reflectance | Simulated reflectance from PARASOL as seen at the top of the atmosphere for 5 solar zenith angles. Valid only over ocean and for one viewing direction (viewing zenith angle of 30 degrees and relative azimuth angle 320 degrees). | | 
-| cltcalipso | cloud_area_fraction | % | CALIPSO Total Cloud Fraction  | | | 
-| cllcalipso | cloud_area_fraction_in_atmosphere_layer | % | CALIPSO Low Level Cloud Fraction  | | | 
-| clmcalipso | cloud_area_fraction_in_atmosphere_layer | % | CALIPSO Middle Level Cloud Fraction  | | | 
-| clhcalipso | cloud_area_fraction_in_atmosphere_layer | % | CALIPSO High Level Cloud Fraction  | | | 
- 
- 
-===== 
- 
- 
-==Sampling of cloud-top quantities== 
- 
-The idea is to use the cloud overlap assumption (maximum, random, or maximum-random) to estimate which part of the cloud in a  \\ layer can be seen from above. 
- 
-Note: For the CCN, whether to sample it in the same way as CDNC, or use a similar apporach (going from bottom up)  \\   
-to sample it at cloud base depends on your parameterization of the activation. 
- 
-    let i=1,2,...,nx be the index for the horizontal grid-points 
-    let k=1,2,...,nz be the index for the vertial levels, with 1 being the uppermost level, and nz the surface level  
- 
-naming convention for the 3D input fields: 
- 
-    iovl is the flag to select the overlap hypothesis 
-    cod3d(nx,nz) cloud optical thickness 
-    f3d(nx,nz) cloud fraction 
-    t3d(nx,nz) temperature 
-    phase3d(nx,nz) cloud thermodynamic phase (0: entire cloud consists of ice, 1: entire cloud consists of liquid water, between 0 and 1: mixed-phase) 
-    cdr3d(nx,nz) cloud droplet effective radius 
-    icr3d(nx,nz) ice crystal effective radius 
-    cdnc3d(nx,nz) cloud droplet number concentration  
- 
-thres_cld = 0.001 \\  
-thres_cod = 0.3 \\  
-IF ( iovl = random OR iovl = maximum-random ) THEN 
-  clt(i) = 1. 
-ELSE 
-  clt(:) = 0 
-ENDIF \\  
-icc(:) = 0 \\  
-lcc(:) = 0 \\  
-ttop(:) = 0 \\  
-cdr(:) = 0 \\  
-icr(:) = 0 \\  
-cdnc(:) = 0 
- 
- 
-DO i=1,nx 
- DO k=2,nz ! assumption: uppermost layer is cloud-free (k=1) 
- IF ( cod3d(i,k) > thres_cod and f3d(i,k) > thres_cld ) THEN ! visible, not-too-small cloud 
- ! flag_max is needed since the vertical integration for maximum overlap is different from the two others: for maximum, clt is the actual cloud cover in the level, for the two others, the actual cloud cover is 1 - clt 
- ! ftmp is total cloud cover seen from above down to the current level 
- ! clt is ftmp from the level just above 
- ! ftmp - clt is thus the additional cloud fraction seen from above in this level 
- 
- IF ( iovl = maximum ) THEN 
- flag_max = -1. 
- ftmp(i) = MAX( clt(i), f3d(i,k))  ! maximum overlap  
- ELSEIF ( iovl = random ) THEN 
- flag_max = 1. 
- ftmp(i) = clt(i) * ( 1 - f3d(i,k) ) ! random overlap  
- ELSEIF ( iovl = maximum-random ) THEN 
- flag_max = 1. 
- ftmp(i) = clt(i) * ( 1 - MAX( f3d(i,k), f3d(i,k-1) ) ) / & 
-                ( 1 - MIN( f3d(i,k-1), 1 - thres_cld ) )  ! maximum-random overlap  
- ENDIF 
- ttop(i) = ttop(i) + t3d(i,k) * ( clt(i) - ftmp(i) )*flag_max  
- 
- ! ice clouds 
- icr(i) = icr(i) + icr3d(i,k) * ( 1 - phase3d(i,k) ) * ( clt(i) - ftmp(i) )*flag_max  
- icc(i) = icc(i) + ( 1 - phase3d(i,k) ) * ( clt(i) - ftmp(i) )*flag_max  
-  
- ! liquid water clouds 
- cdr(i) = cdr(i) + cdr3d(i,j) * phase3d(i,k) * ( clt(i) - ftmp(i) )*flag_max  
- cdnc(i) = cdnc(i) + cdnc3d(i,j) * phase3d(i,k) * ( clt(i) - ftmp(i) )*flag_max  
- lcc(i) = lcc(i) + phase3d(i,k) * ( clt(i) - ftmp(i) )*flag_max  
-  
- clt(i) = ftmp(i) 
- ENDIF ! is there a visible, not-too-small cloud? 
- ENDDO ! loop over k 
- 
- IF ( iovl = random OR iovl = maximum-random ) THEN 
- clt(i) = 1. - clt(i) 
- ENDIF 
-ENDDO ! loop over I 
- 
- 
-naming convention for the input variables: 
- 
-    utctime current time of the day in UTC in seconds   
-    time_step_len length of model time-step   
-    lon(nx) longitude in degrees from 0 to 360    
- 
- ==== Q/A ==== 
- 
-    2D cloud fields (lwp, iwp, cdr, cdnc, cod): Please compute them from grid-box mean values at each level but DO NOT divide by the total (2D) cloud cover, which will be done in analysis after averaging in time and space.  
-          
-    The three months 1 October - 31 December 2005  are thought as spin-up, which can of course be longer. Please choose as overlap assumption the one you use in the radiation scheme.   
-     
-    ATTENTION: clt(i) has to be initialized to 1 for random or maximum-random overlap assumptions in the "satellite simulator"   
- 
-   CCN definition: Compute CCN using Kohler theory at 0.1 and 0.3 % supersaturation. 
-          
-     
-===== 
- 
-  
  
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