Setting the input parameters¶
In this chapter we provide detailed information on how to configure the parameters of the regional EMEP/MSC-W model.
In general the parameters and pathes to the input files can all be set in the configuration file config_emep.nml (a fortran namelist).
config_emep.nml¶
The default parameter, constants and flags are defined in Config_module.f90, and they can be overwritten by config_emep.nml settings.
Here is an example of content of the most important parameters:
&Model_config
GRID = 'EECCA',
iyr_trend = 2015,
runlabel1 = 'Base',
runlabel2 = 'Opensource_Setup_2022',
startdate = 2015,01,01,00,
enddate = 2015,01,10,24,
spinup_enddate = 2015,01,02,06,
DataPath(1) = '../input', ! define 'DataDir' keyword
meteo = '../meteoYYYY/GRID/meteoYYYYMMDD.nc',
DegreeDayFactorsFile = 'MetDir/DegreeDayFactors.nc',
!------------------------------
EmisDir = 'DataDir/GRID',
emis_inputlist(1)%name= 'EmisDir/gridPOLL', !example of ASCII type
emis_inputlist(1)%type = 'GNFR_CAMSsectors',
!--------Sub domain x0, x1, y0, y1
RUNDOMAIN = 36, 100, 50, 150, ! EECCA sub-domain
&end
In the extract above, the model is run for the period 1 January to 10 January 2015 and the trend year used is 2015,
with output staring at 6 UTC on January 2nd.
The startdate must correspond to a time step on the input meteorology,
enddate and spinup_enddate can be chosen freely.
Output files will be stored with the name ‘Base’ and the meteorological correspond to the ‘EECCA’ grid.
Note the definition of the meteorological input (“meteo”): the keywords, ‘YYYY’, ‘MM’, ‘DD’ and ‘GRID’ will be replaced on the fly by respectively, year, month, day and grid (‘EECCA’ here).
It is possible to run the model on a smaller domain than the full
regional model domain, as defined by indexes \(x\) and \(y\).
For the ‘EECCA’ grid \(x=1,\ldots,132; y=1,\ldots,159\).
To set a smaller domain, use RUNDOMAIN variable in the ModelConstants_config
namelist to indicate the sub-domain indexes. In the config_emep extract above,
RUNDOMAIN defines a subdomain with \(x=36,\ldots,100; y=50,\ldots,150\).
The indices refer always to the meteo grid (starting from 1).
If the indices are outside the grid, only the portion within the full grid is taken into account.
Base run¶
To run the model you need access to the executable (emepctm) and the config_emep.nml files.
The path to the other input files are defined by defaults or set in the config_emep.nml file.
To run the model you can either run interactively (mostly for short run), using something similar to (it depends on your system):
mpirun emepctm
For longer runs you should run the model as a batch job (the details will depend on your system). If the run was successful, a message
programme is finished
will be stated at the end of the standard output (screen or some appropriate file for batch jobs).
The model results will be written to the same directory. Please make sure there is enough disk place for the model
results. For more information about the model result output files,
see ch-output.
If for some reason the model crashed, please check both the log and the error file for any clue of the crash. After fixing the problem the job can be submitted again.
The variables wanted in the output are specified in the
OutputConcs, DDEP_ECOS, DDEP_WANTED, WDEP_WANTED and OutputVegO3
parameters for surface concentrations, depositions and other miscellaneous outputs.
- The main ouput files are
Base_fullrun.nc gives values averaged over the entire simulation. This file has always 1 record and the data is an average over the the period startdate to enddate.
Base_month.nc average over each calendar month (12 records for a yearly run)
Base_day.nc averages over 24 hours, starting at 06:00 UTC (each record gives average values between 06:00 and 06:00 the next day. The first time step is written out at 06:00 hr on 2Jan (i.e the first 6 hours are “lost”). The last record may also be averaged only until the end of the run, and not at 06:00.)
Base_hour.nc, averaged over 1 hour.
Base_hourInst.nc, instantaneous values every hour.
Source Receptor (SR) Runs¶
The EMEP/MSC-W model can be used to test the impact of reduced emission of one or more pollutants from a particular country or a number of countries. Such runs are called “Scenario runs”. They are used for source-receptor calculations.
Emission factors for reduced emissions of pollutants from different
sectors and countries can be defined in the input file femis.dat.
The path to this file can be set in config_emep.nml, femisFile = /my/path/femis.dat
Name sector sox nox co voc nh3 pm25 pmco
27 0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
This base run example means that there are (1.0), no emission reductions of SOx, NOx, CO, VOC, NH3, PM2.5 and PMco from all sectors in the UK.
The first column of the second line represents the country code. (27 is the code for UK.) The codes for all countries can be found in Fortran module
Country_mod.f90or at (http://www.emep.int/grid/country_numbers.txt). The country code must be the same as in the emission files for the given country. Some countries and areas are divided into sub-areas in the emission files. In this case, one line for each sub-area has to be included into thefemis.datfile. Countries and areas where emissions are given for sub-areas include the Russian Federation, Germany and all sea areas. “0” means all countries.The second column of the second line represents the sector and “0” means all sectors. Here one can write the appropriate sector code if the emission is reduced only from a specific sector. The description of each sector can also be found in the Fortran module
EmisDef_mod.f90.The columns under the pollutant names show the emission factors for the given pollutants. For example, 0.7 would mean 70% of the original emission, thus 30% reduction.
The first line is important, it must consist of two words followed by the names of the pollutants emitted (in any order).
An example of femis.dat file describing 50% reduced emission of NH3
from sector 10 (the emission from agriculture) in the UK is shown in
Listing 6 and Listing 7.
Name sector sox nox co voc nh3 pm25 pmco
27 10 1.0 1.0 1.0 1.0 0.5 1.0 1.0
Or alternative syntax using country ISO short names:
Name sector sox nox co voc nh3 pm25 pmco
Country UK 10 1.0 1.0 1.0 1.0 0.5 1.0 1.0
Instead of entire countries, reductions can also be specified by coordinates (and combined with country reductions).
The line with coordinate corrections must start with the keyword lonlat.
The coordinates are given in longitude latitude (min and max and the coordinates of the centre of the gridcells are tested.
Gridcells are either entirely included or entirely reduced, never cut into smaller parts).
Name 7 sox nox co voc nh3 pm25 pmco
17 0 1.0 1.0 1.0 1.0 1.0 0.5 0.5
lonlat 3.3 7.2 50.7 53.5 17 0 1.0 1.0 1.0 1.0 0.0 1.0 1.0
In Listing 8, country with code 17 (NL) will reduce PM2.5 and PM10 emissions by half for all sectors. Emissions of NH3 from country with code 17 only, will be removed from the rectangle with longitudes between 3.3 and 7.2 degrees East, and between 50.7 and 53.5 degrees North. Use zero (0) as country code to specify that emissions from all countries should be reduced.
Separate hourly outputs¶
The Base_hour.nc and Base_uEMEP_hour.nc files can become very large. It is possible to split them into one file per day by adding
the keyword `HOURLYFILE_ending = 'JJJ.nc' `, in the configuration file. `JJJ`,
will be automatically replaced by the corresponding day of the year (i.e. a number from 1 to 366 giving for instance Base_hour_001.nc).
The full date as in Base_hour_20180101.nc can be obtained by defining `HOURLYFILE_ending = 'YYYYMMDD.nc' ,`.
Using and combining gridded emissions¶
The gridded emission files are controlled via the config_emep.nml
file. Each file is assigned as one set of values for emis_inputlist.
Listing 9 line 1 includes an ASCII emission file, where the
keyword POLL will be replaced by the model by all the
emitted pollutants (according to the names defined in CM_EmisFiles.inc).
An additional NetCDF emission is included in line 2.
Now all emissions from both ASCII file and NetCDF file will be used. In
practice some countries might be counted twice. Therefore some new data
can be included in the emis_inputlist, to specify which countries to
keep or to avoid. Listing 9 lines 3–4
will include only ‘NO’, ‘SE’ and ‘FI’ from the first file (ASCII), and
take all countries except ‘NO’, ‘SE’ and ‘FI’ from the second file
(NetCDF).
Sets of countries can in principle be defined; for now only the set ‘EUMACC2’ is defined.
emis_inputlist(1)%name = '/MyPathToEmissions/emislist.POLL',
emis_inputlist(1)%type = 'GNFR_CAMSsectors',
emis_inputlist(2)%name = '/MyPathToEmissions/Emis_GLOB_05.nc',
emis_inputlist(1)%incl(1:) = 'NO','SE','FI',
emis_inputlist(2)%excl(1:) = 'NO','SE','FI',
emis_inputlist(1)%PollName(1:2) = 'voc','sox',
It is also possible to restrict the number of pollutants from each of the files.
If not all pollutants from CM_EmisFiles.inc are to be read, one can specify a list of pollutants to be included
using “PollName”. For instance in the example above , the last line specifies that emissions will include only VOC
and SOx from the file defined by emis_inputlist(1)%name.
If PollName is not specified at all, all pollutants are included (therefore all pollutants
from emis_inputlist(2)%name will be included).
The specified pollutants must already be defined in CM_EmisFiles.inc.
It is possible to disregard the “lonlat” reductions introduced by femis.dat for specific emissions. To do this use the “use_lonlat_femis” flag.
Example: switch off emissions covering one region from Emis_GLOB_05.nc as specified by femis, and replace the emissions in that data using emislist.POLL. use_lonlat_femis = F will switch off the reductions, therefore the lonlat coordinate in femis.dat should match the domain covered by emislist.POLL.
emis_inputlist(1)%name.¶emis_inputlist(1)%name = '/MyPathToEmissions/emislist.POLL',
emis_inputlist(1)%use_lonlat_femis = F,
emis_inputlist(2)%name = '/MyPathToEmissions/Emis_GLOB_05.nc',
An alternative way of combining overlapping emissions, is to use a “mask” approach. This is typically used, when the emissions of one city is known in more details, but one wish to include default regional or global emissions elsewhere. The city emissions are used to set the mask, and that mask is then in turn used by the second emission sources to turn off emissions within the city.
emis_inputlist(1)%name = '/MyPathToEmissions/emis_local.POLL',
emis_inputlist(1)%set_mask = T,
emis_inputlist(2)%name = '/MyPathToEmissions/Emis_GLOB_05.nc',
emis_inputlist(2)%use_mask = T,
There are some details one should take into account: the order of the “set_mask” and “use_mask” matter. The mask should be set before it is used; “before” meaning that the indice of “emis_inputlist” is lower. Also yearly emissions are treated before monthly emissions, therefore one should not use monthly emissions to mask yearly emissions. The mask is set for a given position if emissions at that point are larger than 1.0e-20. If emissions are zero at some point the mask will not be set for that point, and regional emissions will be included there. There is only one mask. Several emissions files can set and use the mask.
Masks can also be set from any field, see own section below.
Nesting¶
The model can be run in a large domain and all the concentrations of pollutants stored at fixed intervalls (3 hours typically). Then we can define a smaller region within the large domain, and rerun the model in the smaller region, using the stored concentrations at the domain boundaries. It is then possible to make a simulation in a restricted region with fine resolution, but still taking account the effect of pollutants from outside the small region. This is called nesting. The large domain defines the Boundary Conditions (BC, which are only used at the boundaries of the small domain), and possibly the Initial Conditions (IC, which must be defined everywhere in the small domain, but only for the start date).
Depending on what is wanted different “Nesting modes” can be defined.
The different options are controlled by the NEST_MODE_READ and NEST_MODE_SAVE variables in Model_config in config_emep.nml file.
The mode options are:
NEST_MODE_READ- ‘NONE’
do nothing (default).
- ‘START’
read at the start of run.
- ‘RESTART’
read at the start of run, but do not overwrite BC. Use this option when you restart a run
without changing the domain size (“checkpoint-restart”). The difference with “START” is only that BC are not overwritten. (This is important in the case of restarting exactly at the start of a month (at time 00:00, the 1st), because the nest file contains the BC from preceding month, and if ‘START’ is used it will use those for the new month, i.e. overwrite new BC with old ones.)
- ‘NHOUR’
read at given
NEST_NHOURREADhourly intervals, if the file is found.NEST_NHOURREADis set inModel_configand should be an integer fraction of 24.- ‘MONTH’
read at start of each month.
NEST_MODE_SAVE- ‘NONE’
do nothing (default).
- ‘END’
write at end of run.
- ‘NHOUR’
write at given NEST_NHOURSAVE hourly intervals.
NEST_NHOURSAVEis set inModel_configand should be an integer fraction of 24.- ‘MONTH’
write after each month (used for checkpoint/restart for instance).
The name of the file to write to is defined by NEST_template_write (also in Model_config).
The name of the file to read to IC data from is defined by NEST_template_read_3D.
The name of the file to read to BC data from is defined by NEST_template_read_BC; it can be the same file as NEST_template_read_3D.
If for example NEST_NHOURSAVE=3, but NEST_NHOURREAD = 1, the data is interpolated in time to get a smooth transition between the 3-hourly values (recommended).
In addition, 3D outputs can be asked for at specific date. Example:
&Model_config
[...]
NEST_OUTDATE_NDUMP = 2, ! choose two dates
NEST_outdate(1)= 2019,01,01,00, ! save at end of the 2018 year
NEST_outdate(2)= 2018,05,17,00, ! save also 17th of May 2018
&end
Example write BCs¶
Listing 13 shows an example to write every 3 hours into
daily Nest/BC files. Output file name is defined by NEST_template_write (‘BC_YYYYMMDD.nc’),
where ‘YYYYMMDD’ is replaced by corresponding date.
All advected model variables will be written out for the sub-domain defined
by NEST_out_DOMAIN (\(x=60,\ldots,107; y=11,\ldots,58\)).
If no NEST_out_DOMAIN is given, the entire model rundomain will be written out.
&Model_config
[...]
NEST_MODE_READ = 'NONE', ! do not read BC
NEST_MODE_SAVE = 'NHOUR', ! write BCs
NEST_NHOURSAVE = 3, ! every 3 hours
NEST_template_write = 'BC_YYYYMMDD.nc' ! to your (daily) BC output file
! (8 records per file)
!-------- Sub domain for write modes
NEST_out_DOMAIN = 60,107,11,58, ! istart,iend,jstart,jend
&end
Read BCs produced by a previous EMEP MSC-W model run¶
Listing 14 shows an example to read every 1 hours from
the Nest/BC files created previously by running Listing 13.
Please note that the model sub-domain for a nested run is set by RUNDOMAIN,
as shown in Listing 4.
&Model_config
[...]
NEST_MODE_READ = 'NHOUR', ! read external BC
NEST_NHOURREAD = 1, ! every hour
NEST_template_read_BC = 'BC_YYYYMMDD.nc' ! your (daily) BC input file
NEST_MODE_SAVE = 'NONE', ! do not write BCs
&end
Note that NEST_NHOURREAD can (and should) be smaller than the value used for NEST_NHOURSAVE.
The values between saved dates will then be interpolated in time, giving a smoother transition.
Reduce the size of BC files¶
The size of the files obtained in a nesting configuration can be very large if the out_DOMAIN is large.
If the inner domain is known in advance, only the part matching exactly the part needed to construct the BC of the small domain can be stored.
Define NEST_MET_inner in &Model_config, which should be a link to any metdata of the inner grid;
it will only be used to define the projection parameters of the inner grid (i.e. dates and other content do not matter).
&Model_config
[...]
NEST_MET_inner = 'inner_domain/wrfout_d03_2015-01-01_00:00:00',
NEST_RUNDOMAIN_inner = 12, 136, 100, 300,
&end
You cannot use the implicit dates (“YYYY” etc.); you must put explicit numbers. Note that the file will have the same dimensions, but zeros are put into the unused parts. The NetCDF internal compression will take care of reducing the actual size, as measured by used disc space.
If a BC file has been created using the NEST_MET_inner method, it cannot be used for initializating concentrations at the start of the run.
A separate file has to been created for initializations.
This file can then be used by the inner grid by defining NEST_template_read_3D in config_emep.nml.
Read external BCs¶
So far only BC created by the model itself have been used.Reading external BCs, i.e. produced by other means (another model for example) is more involved. The chemical species may be different and the vertical levels also. The vertical axis and variables in the file need then to be mapped to the corresponding model variables.
Listing 16 shows an example to read every 3 hours from an external
BC file. The model will read 3 variables from MyBC.nc: O3, NO, and NO2.
The maping between the MyBC.nc variables and the corresponding model variables
is defined in the ExternalBICs_bc namelist.
&Model_config
[...]
NEST_MODE_READ = 'NHOUR', ! read external BC
NEST_NHOURREAD = 3, ! every 3 hours
NEST_template_read_BC = 'MyBC.nc' ! from your BC input file
NEST_MODE_SAVE = 'NONE', ! do not write BCs
USE_EXTERNAL_BIC = T,
EXTERNAL_BIC_NAME= 'MyBICScenario', ! variable mapping, see ExternalBICs_bc
TOP_BC = T, ! use top BC also from your BC file
filename_eta = 'filename.zaxis',! text file containing the
! description of your BC file
&end
&ExternalBICs_bc
description='MyBICScenario','Version name',3, ! name,version,size
map_bc=! emep,external,frac,wanted,found,IXADV,
'O3' ,'O3_VMR_inst' ,1.0,T,F,-1,
'NO' ,'NO_VMR_inst' ,1.0,T,F,-1,
'NO2','NO2_VMR_inst',1.0,T,F,-1,
&end
Vertical coordinate¶
In order the determine the vertical levels on the external BC file (‘MyBC.nc’ in Listing 16), the following checks will take place in the following order:
- \(\eta\) (eta) coordinate:
If the variable \(hyam\) (hybrid
acoefficient at layer midpoint) is found, \(\eta\) is calculated from \(hyam\) and \(hyam\) variables on the file.
- \(\sigma\) (sigma) coordinate:
If the vertical level is indexed by variable
k.
- \(\eta\) coordinate:
If the file defined by variable
filename_etaexist (‘filename.zaxis’ in Listing 16), \(\eta\) is derived fromvctandvctsizevariables on the file.
- pressure coordinate:
If the vertical level is indexed by variable
lev.
Independent of the coordinates of the BC file,
the BC levels will be interpolated into EMEP model levels.
If the BC file level structure is not recognized,
and there is no filename_eta provided,
the model will write an error message and stop execution.
An example of the filename_eta for EMEP model levels is given below.
Here the vct variable describes the model level boundaries in hybrid eta coordinate:
zaxistype = hybrid
size : 20
name : k
longname : vertical sigma coordinates
units : sigma_level
levels : 0.0200 0.0600 0.1000 0.1425 0.1950 0.2635 0.3470
0.4365 0.5215 0.5990 0.6695 0.7330 0.7895 0.8390
0.8815 0.9170 0.9455 0.9670 0.9820 0.9940
vctsize = 42
vct =
10000. 09600. 09200. 08800. 08350. 07750. 06980.
06080. 05190. 04380. 03640. 02970. 02370. 01840.
01380. 00990. 00670. 00420. 00240. 00120. 00000.
0.0000 0.0400 0.0800 0.1200 0.1650 0.2250 0.3020
0.3920 0.4810 0.5620 0.6360 0.7030 0.7630 0.8160
0.8620 0.9010 0.9330 0.9580 0.9760 0.9880 1.0000
vct is the vertical coordinate table describing the hybrid a and b
paramters at the layer interfaces in \(\eta\) coordinate system
(\(hyai\) and \(hybi\)). They must respect the following constraints:
\(hyai_1=0\) and \(hybi_1=1\);
\(hyai_0=P_t\) and \(hybi_0=0\).
\(P_t\) is the pressure at top of the model domain.
In this file, the first 21 values in vct represent \(hyai\)
and the remaining 21 represent \(hybi\) values in hPa.
Variable mapping¶
The variables to be used from the external boundary condition data are
given in the ExternalBICS_bc namelist in the config_emep.nml file.
In Listing 16, map_bc maps 3 variables in the ‘MyBC.nc’ file to
3 model variables (O3, NO, and NO2).
On each line of map_bc contains the 6 elements:
Variable name in EMEP MSC-W model, e.g. ‘O3’.
Variable name in the External BC data file, e.g. ‘O3_VMR_inst’.
External BC component to EMEP component fraction, e.g. 1.0.
Is this component wanted or not, set to T or .true. to read the variable.
Was the BC variable found on the file, will be set by the model on run time.
Index of the advected model variable, will be set by the model on run time.
The fraction is helpful, when one has to map a variable that is explicitly not in the model but a fraction of that variable can be mapped to a matching variable in the model.
Unit conversions are delegated to the Units_mod.f90 module.
The supported units are: \(\mu g/m^3\), \(\mu g(S)/m^3\), \(\mu g(N)/m^3\), \(\mu g(C)/m^3\), ppb,
mixing ratio (mol/mol) and mass mixing ratio (kg/kg).
If the BC data has different units,
either convert them into one of the above mentioned units in pre-processing
or add the respective conversion factor in the module Units_mod.f90.
config: Europe or Global?¶
The EMEP model has traditionally been run on the EMEP grid covering Europe, and using meteorology from the ECMWF IFS model. In this environment, we typically set several configuration variables to make use of Euro-specific data. In other regions it is better to make use of the model’s ‘global’ settings, which will ensure better handling of vegetation (eg LAI) changes, convection, and various emission settings.
USES%DEGREEDAY_FACTORS = T, ! though F is okay too
USES%PFT_MAPS = F,
USES%MonthlyNH3 = 'LOTOS', ! Better monthly profile, for Europe only!
USES%CONVECTION = F,
USES%SOILNOX_METHOD = 'NoFert', ! If using ECLIPSEv6
USES%DEGREEDAY_FACTORS = F
USES%PFT_MAPS = T, ! PFT LAI tests
USES%MonthlyNH3 = '-', ! Better monthly profile, for Europe only!
USES%CONVECTION = T,
The DEGREEDAY_FACTORS setting triggers the use of degree-days in
controlling residential combustion (GNFR C/SNAP2) emissions. This requires pre-processed files of heating degree days.
Such files (DegreeDayFactors.nc) can be produced from any meteorology, but the difference in
results even for Europe is not too significant. In other regions of the
world emissions from residential combustion may not be as dependent on degree-days as in
Europe, and so this setting should probably be false.
PFT_MAPS=T triggers the use of a global file which provides monthly
variations in leaf area index (LAI) for different vegetation types. This
controls deposition and biogenic VOC emission parameters. In Europe, a
simpler latitude-dependent system is used (based upon DO3SE), and so
PFT_MAPS should be set F.
MonthlyNH3='LOTOS' is also only relevant for European simulations; and
indeed any non-European runs are better off with monthly emissions for
that particular area. To disable the monthly NH3 profile from LOTOS-EUROS
and instead use the monthly profile defined, for example, in the
MonthlyFacFile, set MonthlyNH3='-' explicitly. If not set explicitly,
MonthlyNH3='LOTOS' will be set automatically for European simulation runs.
CONVECTION is difficult. In principle, all models runs should use the T
setting, but for Europe we find it degrades the model results too much
and we use F. The problem is likely that the sub-grid processes behind
convection are so complex and the paramererisation is very uncertain.
Note also that in Config_module we have the default setting CONVECTION_FACTOR=0.33,
which may be changed to allow more or less influence of this variable.
config: SOILNOX¶
USES%SOILNOX_METHOD = 'NoFert', ! If using ECLIPSEv6 or EMEP European
USES%SOILNOX_METHOD = 'Total', ! If using ECLIPSEv5
The model makes use of global 0.5 degree data from the CAMS81 project, but the user needs
to specify the data to be used from this system.
The choice, between Total and NoFert depends
on the anthropogenic emission inventory in use. If this anthropogenic inventory
already includes fertlizer-induced soil NO emissions, then the NoFert data from
the soil-NO system is used. If not, choose Total.
Country Variable (CV) format¶
In the CV format, emissions are organised in a number of files (Emis_sourceFiles(i_file)), each files containing a number of sources (Emis_sourceFiles(i_file)%source(j_source)). A source can be any 2D field. It can also be a 3D field, if the third dimension is the sector. The sources are associated to country through a country code or a country code. The file must have a ‘lon’ and a ‘lat’ variable, showing longitude and latitudes of each grid point. ‘lon’ and ‘lat’ must be 1D variables if the projection is ‘lon lat’, 2D otherwise.
The code directory contain a Python script that can create an emission file in this format: emissions_TXT2ncCV.py
- The file and sources can be characterized by a set of variables. In general these variable can be set by, and in order of increasing priority:
Default value
Global attribute read in the netcdf file
Variable attribute read in the netcdf file
Value set for Emis_sourceFiles(i)%XXX in config_emep.nml
Value set for Emis_sourceFiles(i)%source(s)%XXX in config_emep.nml
- Exceptions to the priority rule are:
maskID cannot be set by attributes in the netcdf file
the file and source ‘factor’ are on top of each other, not replaced
boolean parameters (like apply_femis), are used as “and” (i.e. if any is false, the result is false)
- List of file attributes (default in parenthesis):
filename (‘NOTSET’) Name of the file (with path)
projection (‘lon lat’) Only three categories ‘lon lat’, ‘native’ or any other (for example ‘Lambert ‘or ‘Stereographic’ would give the same result). ‘native’ means that emissions are given in the same grid as the model grid and the data is not interpolated (use it if you can).
grid_resolution (an approximate value is computed from the lon and lat, if no value is given). It does not need to be exact (cannot be exact on a sphere anyway!). This grid_resolution steers the interpolation algorithm; A large value will force the code to subdivide each emission gridcell in large number of pieces, that are assigned to the model grid. Larger values means smoother interpolation, but more cpu time.
periodicity (‘time’) How often the values are updated. Can be ‘yearly’, ‘monthly’, ‘hourly’ or ‘time’. ‘hourly’ or ‘time’ means that the time as defined in the netcdf is used to define when to fetch a new record. The timestamp must correspond to the end of the time period of validity. For ‘yearly’ monthly timefactors are applied, if a sector is defined. For ‘monthly’ and ‘yearly’, an hourly timefactor is applied if a sector is defined. For ‘hourly’ or ‘time’, no additional timefactors are applied.
factor (1.0) multiplicative factor for all sources in the file
units (‘NOTSET’) will be used as default for sources units if set.
apply_femis (true) whether to apply the femis reductions to the sources of this file.
include_in_local_fractions (true) whether to take sources from this file into account for the local fraction calculations
countrycode (-1) will be used as default for sources country code if set. Use rather country_ISO if you can.
country_ISO (‘NOTSET’) will be used as default for sources country ISO code (for example ‘FR’ for France) if set.
sector (-1) will be used as default for sources sector if set.
SECTORS_NAME or sectorsName (‘GNFR_CAMS’) . It must be set to one of the SECTORS%name defined (‘GNFR_CAMS’ for example).
mask_ID (‘NOTSET’) the name of the mask, if you want to apply one.
mask_ID_reverse (‘NOTSET’) the name of the mask, if you want to apply one in the complementary region.
country_ISO_incl (‘NOTSET’) If used, only use emissions from the countries in the list (see example below)
country_ISO_excl (‘NOTSET’) If used, do not take into account emissions from countries in the list (see example below)
- List of source attributes:
varname (‘NOTSET’) The name as used in the netcdf file
species (‘NOTSET’) Either one of the emission group species, as defined in CM_EmisFile.inc (generally sox, nox, pm25, pmco, nh3, co, voc)
factor (1.0) multiplicative factor. Can be used to change units to model definitions. Comes on top of the file multiplicative factors and possibly other factors.
units (‘mg/m2/h’) Units after the factor multiplication.
countrycode (-1) will be used as default for sources country code if set. Use rather country_ISO if you can.
country_ISO (‘N/A’) the country code, as defined in Country_mod.f90 (for example ‘FR’ for France). ‘N/A’ is a valid code, but it does not correspond to any country.
apply_femis (true) whether to apply the femis reductions to this source.
include_in_local_fractions (true) whether to take this source into account for the local fraction calculations
mask_ID (‘NOTSET’) the name of the mask, if you want to apply one.
mask_ID_reverse (‘NOTSET’) the name of the mask, if you want to apply one in the complementary region.
If a dimension with name “sector” is found, it is assumed that the third dimension of emission variables represent the sector idex.
The idea is that only variables that clearly are required in a specific context need to be set; if the value can be inferred from other information, the code should do it. Depending of the type of source, not all variables are used.
- Note about species: These can be interpreted in one of three categories
emitted species (nox,sox,pm25 …) with sector (1…11 (or 13)) (“sector species”)
individual species (SO2, NO, NO2, …) with sector. The species MUST be one of the splitted species. These will be treated as one of the “sector species” from 1. (but not splitted of course). Careful with units, it follows the same rules as “sector species”; molecular weight for SO4 for example is considered “as SO2” and NO “as NO2”. You can correct the units using the factor attribute.
individual species (SO2, APINENE, O3 …) without sector (<=0, or not specified). No timefactors, vertical realease heights or splits are applied. In this case the emissions are summed up in setup_rcemis (not in EmisSet)
Example:
Emis_sourceFiles(1)%filename = '/path/ECLIPSE_V6a_CLE_base_PM25.nc',
Emis_sourceFiles(1)%sectorsName = 'GNFR',
Emis_sourceFiles(1)%projection = 'lon lat',
Emis_sourceFiles(1)%periodicity = 'yearly',
Emis_sourceFiles(1)%source(1)%varname='emis_tra',
Emis_sourceFiles(1)%source(1)%species='pm25',
Emis_sourceFiles(1)%source(1)%sector=6,
Emis_sourceFiles(1)%source(1)%factor=1000000.0,!kt->kg
Emis_sourceFiles(1)%source(1)%units='kg',
If two CV emission files are wished to be combined in a single simulation, for example so that different emission scenarios can be applied inside and outside of the EMEP region (UNECE excl. NA), one can use the Emis_sourceFiles(1)%country_ISO_excl(1:) and Emis_sourceFiles(1)%country_ISO_incl(1:) options. The below dummy example applies a 2015 baseline scenario inside the EMEP region and 2050 MFR scenario in the rest of the world (ROW), based on 0.5 degree emission input data files.
Emis_sourceFiles(1)%filename = '/path_to_global_0.5deg_2015_baseline.nc',
Emis_sourceFiles(2)%filename = '/path_to_global_0.5deg_2050_MFR.nc',
Emis_sourceFiles(1)%country_ISO_incl(1:48) = "AL", "AM", "AT", "AZ", "BY", "BE", "BA", "BG", "CY", "CZ", "DE",
"DK", "EE", "FI", "FR", "GE", "GR", "HR", "HU", "IS", "IE", "IT",
"LV", "LT", "LU", "MT", "NL", "NO", "PL", "PT", "MD", "RO", "SI",
"ES", "SE", "CH", "MK", "TR", "SK", "UA", "RS", "ME", "GB", "KG",
"RUSS_EURO", "RUSS_ASIA", "KZT", "FSUA",
Emis_sourceFiles(2)%country_ISO_excl(1:48) = "AL", "AM", "AT", "AZ", "BY", "BE", "BA", "BG", "CY", "CZ", "DE",
"DK", "EE", "FI", "FR", "GE", "GR", "HR", "HU", "IS", "IE", "IT",
"LV", "LT", "LU", "MT", "NL", "NO", "PL", "PT", "MD", "RO", "SI",
"ES", "SE", "CH", "MK", "TR", "SK", "UA", "RS", "ME", "GB", "KG",
"RUSS_EURO", "RUSS_ASIA", "KZT", "FSUA",
Masks¶
Typically you have got fine scale emissions for a small region of interest, a city for instance. You may want to remove that area from the coarse scale emissions, and replace it with your own. The mask allows you to define a specific region (the mask). To define which gridcells to include in your local region, you must find a suitable variable that shows the region of interest. It could be for example the PM emissions in your local area.
A “mask” can be defined for instance with:
EmisMask(1)%filename = '/mypath/myfile.nc', ! name of the netcdf file to read from
EmisMask(1)%cdfname = 'London_PM', ! name of the variable to read from the file
EmisMask(1)%type = 'CELL-FRACTION', ! the mask value is part of the reduction, default
EmisMask(1)%ID = 'LONDON', ! the name you give to that mask
EmisMask(1)%fac = 0.85, ! muliplicative factor to use. Default 0.0
! define species to be read from the emission file separately, as if reading from different files
Emis_sourceFiles(1:7)%filename=7*'path/Emis_CAMS_v5_1_with_Ref2_0_1_GNFR_CAMS_01005deg_2018_CAMS2_40_U5.nc',
Emis_sourceFiles(1:7)%species='sox','nox','voc','nh3','co','pm25','pmco',
! apply mask to pm25 and pmco emissions
Emis_sourceFiles(6:7)%mask_ID =2*'London_PM',
EmisMask(1)%filename = '/mypath/myfile.nc', ! name of the netcdf file to read from
EmisMask(1)%cdfname = 'London_PM', ! name of the variable to read from the file
EmisMask(1)%type = 'THRESHOLD',
EmisMask(1)%ID = 'LONDON', ! the name you give to that mask
EmisMask(1)%threshold = 1.0E-10, ! the mask is set at any point larger than the threshold
EmisMask(1)%threshold_max = 100, ! ... and smaller than the threshold_max value (default 1E60)
EmisMask(1)%fac = 0.85, ! muliplicative factor to use. Default 0.0
Several masks can be defined. Each mask is identified by their “ID”. If you want to include in the region also the gridcell which are zero, you can set the threshold slightly negative (-1.0E-10), to include the entire region covered by the variable (otherwise zero values would be defined equivalently to outside of region). To include for example all values=23, but not 24, set EmisMask(1)%threshold = 22.5 and EmisMask(1)%threshold_max = 23.5
A mask defines only a region. It is not directly related to any pollutant.
The masks defined here, will also be applied on files from emis_inputlist (old format), if use_mask is set (but the multiplicative factor is always 0.0 for old format emissions). It is however not possible to set masks by both systems simultaneously. In the old format only one mask can be used at a time. It will be the reunion of all masks produced by the system above (the ID is meaningless and cannot be specified in old format).
To be used with the Local Fractions (see below), one can also define a set of regions defined by integer numbers. For this one must define the ID with the keyword NUMBER:
EmisMask(1)%filename = '/mypath/myfile.nc', !name of the netcdf file to read from
EmisMask(1)%cdfname = 'region_id', !name of the variable to read from the file. The variable must be an integer!
EmisMask(1)%type = 'NUMBER',
EmisMask(1)%ID = 'specific-mask-name',
Other less used options¶
There are many internal settings that are set to a default value by the model.
These default values can often be overridden by setting specific values for keywords in config_emep.nml.
The RUNDOMAIN is divided by the model into subdomains which are assigned to each processor.
Normally this partioning is done such that the X and Y direction are divided into approximately equal number of parts.
For runs in lat lon projection containing poles the Y division is done into one or two parts,
so that each processor has the same share of pole regions.
The default partitioning can be overrided using the DOMAIN_DECOM_MODE parameter in config_emep.nml.
Recognized values are:
‘X*Y’, ‘XY’, ‘X*1’, ‘Y=1’, ‘X’, ‘1*Y’, ‘X=1’, ‘Y’, ‘2*Y’, ‘X=2’, ‘X*2’, ‘Y=2’.
See also in Par_mod.f90 for details.
The main timestep parameter dt_advec can be set manually in config_emep.nml (in seconds, real number).
It must be a factor of 3600.
JUMPOVER29FEB : if set to T , will not treat the 29th of February even for leap years.
(Useful if that date is missing, for instance in Climate runs).
NETCDF_DEFLATE_LEVEL: The level of compression used in the NetCDF output files (integer).
Negative values means netcdf3 format.
END_OF_EMEPDAY: (integer) Hour when to start and end a “day”. For daily averages gives for example averages from 06:00 to 06:00 next day, if END_OF_EMEPDAY = 6.
USES%SKIP_INCOMPLETE_OUTPUT : if T, will skip daily/montly/fullrun output for runs under 1/28/181 days.
Defining own sectors¶
Emissions can be assigned to a sector. A sector defines three properties:
Split into species
Emission height release distribution
Timefactors
The set of splits is defined in files “emissplit.defaults.POLL” and “emissplit.specials.POLL”. The release height distribution can be chosen among the 6 predefined values, or defined in config_emep.nml. The timefactors are defined in “MonthlyFac.POLL” “DailyFac.POLL” and “HourlyFacc.INERIS”.
Which height/split/timefac is chosen for a given sector can be also be controlled by the user. GNFR_CAMS sectors are predefined (SNAP also, but we recommend to use GNFR_CAMS). The values for split, emission release height and timefactors can be defined through settings in the config_emep.nml settings. The following will reproduce the default settings:
SECTORS_ADD(1) = 'GNFR_CAMS', 'GNFR_A', 'sec01', 1, 1, 1, 'Public Power', 'ALL',
SECTORS_ADD(2) = 'GNFR_CAMS', 'GNFR_B', 'sec02', 3, 3, 2, 'Industry', 'ALL',
SECTORS_ADD(3) = 'GNFR_CAMS', 'GNFR_C', 'sec03', 2, 2, 3, 'OtherStationaryComb', 'ALL',
SECTORS_ADD(4) = 'GNFR_CAMS', 'GNFR_D', 'sec04', 5, 5, 4, 'Fugitive', 'ALL',
SECTORS_ADD(5) = 'GNFR_CAMS', 'GNFR_E', 'sec05', 6, 2, 5, 'Solvents', 'ALL',
SECTORS_ADD(6) = 'GNFR_CAMS', 'GNFR_F', 'sec06', 7, 2, 6, 'RoadTransport', 'ALL',
SECTORS_ADD(7) = 'GNFR_CAMS', 'GNFR_G', 'sec07', 8, 2, 7, 'Shipping', 'ALL',
SECTORS_ADD(8) = 'GNFR_CAMS', 'GNFR_H', 'sec08', 8, 7, 8, 'Aviation', 'ALL',
SECTORS_ADD(9) = 'GNFR_CAMS', 'GNFR_I', 'sec09', 8, 2, 9, 'Offroad', 'ALL',
SECTORS_ADD(10) = 'GNFR_CAMS', 'GNFR_J', 'sec10', 9, 6, 10, 'Waste', 'ALL',
SECTORS_ADD(11) = 'GNFR_CAMS', 'GNFR_K', 'sec11', 10, 2, 11, 'AgriLivestock', 'ALL',
SECTORS_ADD(12) = 'GNFR_CAMS', 'GNFR_L', 'sec12', 10, 2, 12, 'AgriOther', 'ALL',
SECTORS_ADD(13) = 'GNFR_CAMS', 'GNFR_M', 'sec13', 5, 5, 13, 'Other', 'ALL',
SECTORS_ADD(14) = 'GNFR_CAMS', 'GNFR_A1','sec14', 1, 1, 1, 'PublicPower_Point', 'ALL',
SECTORS_ADD(15) = 'GNFR_CAMS', 'GNFR_A2','sec15', 1, 3, 1, 'PublicPower_Area', 'ALL',
SECTORS_ADD(16) = 'GNFR_CAMS', 'GNFR_F1','sec16', 7, 2, 16, 'RoadTransportExhaustGasoline', 'ALL',
SECTORS_ADD(17) = 'GNFR_CAMS', 'GNFR_F2','sec17', 7, 2, 17, 'RoadTransportExhaustDiesel', 'ALL',
SECTORS_ADD(18) = 'GNFR_CAMS', 'GNFR_F3','sec18', 7, 2, 18, 'RoadTransportExhaustLPGgas', 'ALL',
SECTORS_ADD(19) = 'GNFR_CAMS', 'GNFR_F4','sec19', 7, 2, 19, 'RoadTransportNonExhaustOther', 'ALL',
The name in the first column (GNFR_CAMS) should match the sector name defined in the emission file, or be given in the config_emep.nml (see example below). The second name can be chosen by the user (it will be used if SecEmisOutWanted is T)), the third name is the variable name ending in the netcdf emission file (the start being the name of the pollutant) only implemented for “fraction” format, the first number refers to the index used for time factors, the second number the index in the Emis_h array, the third number is the index used in the split files. The long name in the second last column is a longer description, and the last column refers to the species to be included for this sector (if they exist in the emission file).
From version 4.45 and onwards, sector type or names are compulsory for each emission file. This can be given either in the config_emep.nml or in the NetCDF file.
Here is an example of how to define a new sector with a new height distribution, used by emissions given in a separate file.
Emis_Zlevels(1:)20.0, 50.0, 92.0, 184.0, 324.0, 522.0, 781.0, 1106.0,
Emis_h(1:,1) = 0.000, 0.000, 0.000, 0.003, 0.147, 0.400, 0.300, 0.150,
Emis_h(1:,2) = 1.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000,
Emis_h(1:,3) = 0.060, 0.067, 0.093, 0.750, 0.030, 0.000, 0.000, 0.000,
Emis_h(1:,4) = 0.050, 0.063, 0.087, 0.700, 0.100, 0.000, 0.000, 0.000,
Emis_h(1:,5) = 0.020, 0.034, 0.046, 0.600, 0.300, 0.000, 0.000, 0.000,
Emis_h(1:,6) = 0.000, 0.000, 0.000, 0.410, 0.570, 0.020, 0.000, 0.000,
Emis_h(1:,7) = 0.200, 0.300, 0.020, 0.044, 0.066, 0.094, 0.123, 0.153,
Emis_h(1:,8) = 0.000, 1.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000,
emis_inputlist(1)%name='GNFR.nc',
emis_inputlist(2)%name='MyEmis.nc',
emis_inputlist(2)%sector='MyNewSector',
SECTORS_ADD(1) = 'MyNewSector', 'MyTestSector', 'MyCar', 7, 8, 6, 'Special car exhaust', 'pm25',
Note that if you define new splits, you must include defaults values in all the default files (even if they are overwritten by the specials).
Local Fractions (under development)¶
When chosen, the Local Fractions (used by the urban EMEP, uEMEP) will be outputted in separate files.
config_emep.nml settings:
USES%LocalFractions = T, ! T for computing Local Fractions, F otherwise
!Local Fractions frequency of output (separate file for each). Can be any of: YEAR, MONTH, DAY, HOUR, HOUR_INST
lf_set%YEAR = T, !average value for full run in output
lf_set%Nvert = 14, !How many vertical level to include in treatment. Should be higher than highest emissions
!NB: for now lf_src(1)%dist will be used for all sources
lf_src(1)%dist = 5, !how far the neighbors can be in each direction (NB: high cost for large dist)
!Local Fractions pollutants and sectors to include:
lf_src(1)%species="pm25", ! any of EMIS_File: "sox ", "nox ", "co ", "voc ", "nh3 ", "pm25", "pmco"
lf_src(1)%sector=0, !0 means sum of all sectors
lf_src(1)%make_fracsum=T,
lf_src(2)%species="pm25", ! any of EMIS_File: "sox ", "nox ", "co ", "voc ", "nh3 ", "pm25", "pmco"
lf_src(2)%sector=0, !0 means sum of all sectors
lf_src(2)%res=5, ! sources are squares with size 5x5 gridcells
lf_src(2)%make_fracsum=T,
lf_src(3)%species="nox ",
lf_src(3)%sector=0,
lf_src(4)%species="nox ",
lf_src(4)%sector=8,
! lf_set%DOMAIN = 370, 420, 270, 320, !which domain to include in output. Will save disk, but not CPU to reduce.
If one wants to include many species, sectors and res values, without writing one entry per source, one can use the following syntax:
USES%LocalFractions = T, ! T for computing Local Fractions
lf_species(1:2)%name = 'pm25','nox',
lf_species(1)%sectors(1:) = 0, 1, 2, 8,
lf_species(1)%res(1:) = 1, 4,
lf_species(2)%sectors(1:) = 0, 1, 2, 8,
lf_species(2)%res(1:) = 1, 4,
The corresponding lf_src values will then be added to the already defined lf_src (3*4*2 = 24 new sources in this example). You can not with this syntax combine different res for different sectors for the same species.
Note that the files can be very large if hourly outputs and/or many neighbors are requested.
Local Fractions for tracing natural emissions (under development)¶
Natural emissions are assumed emitted from surface (in current version). So far only the DMS emissions can be tracked. To include DMS outputs:
lf_src(1)%name = 'DMS',
lf_src(1)%dist = 2, !will track over up to 2 gridcells in all directions
lf_src(1)%nhour = 1, ! will track separately emissions every 1 hour, and reset every 24 hours
lf_set%HOUR_INST = T, ! output instantaneous values every hour
Local Fractions for Source Receptor style runs¶
Local fractions can also be used to make traditional Source Receptor (or blame) matrices, in a single run. (the %res flag is then not used)
USES%LocalFractions = T, ! T for computing Local Fractions
!Local Fractions frequency of output (separate file for each). Can be any of: YEAR, MONTH, DAY, HOUR, HOUR_INST
lf_set%YEAR = T, !average value for full run in output
lf_set%Nvert = 14, !How many vertical level to include in treatment. Should be higher than highest emissions
!Local Fractions pollutants and sectors to include:
lf_src(1)%species="pm25", ! any of EMIS_File: "sox ", "nox ", "co ", "voc ", "nh3 ", "pm25", "pmco"
lf_src(1)%type='country', ! Means make country style SR
lf_src(1)%drydep=T, !means make country dry deposition maps too
lf_src(1)%wetdep=T, !means make country wet deposition maps too
lf_src(2)%species="pmco", ! any of EMIS_File: "sox ", "nox ", "co ", "voc ", "nh3 ", "pm25", "pmco"
lf_src(2)%type='country', ! Means make country style SR
lf_src(2)%drydep=T, !means make country dry deposition maps too
lf_src(2)%wetdep=T, !means make country wet deposition maps too
! Specify which countries and sectors
lf_country%sector_list(1:8)=0,1,2,3,4,5,6,7,
lf_country%list(1:20)='FR','IT','DE','ES','NO','NL','SE','PL','AT','BE','BG','DK','FI','GR','HU','PT','RO','CH','TR','GB',
lf_country%group(1)%name='NORDIC', !any name given to the group (used as output name)
lf_country%group(1)%list(1:)='NO','DK','SE','FI', ! countries included in the group
Instead of defining countries in the emission files, one can define “source regions” in a separate netcdf file. Each region must have an integer value. The values to be included as a source region are then specified by a list or as the minimum and maximum value to include (defining both a list and an intervall is allowed, but only one list and one intervall). The maskfile should be defined too. For example to include masks 2,5,8,12 and all mask between 100 and 357 (included):
EmisMask(1)%filename='municip_mask/municip_mask_500m.nc',
EmisMask(1)%cdfname =region_id',
EmisMask(1)%type ='NUMBER',
EmisMask(1)%ID ='municip_mask',
lf_country%mask_val(1:) = 2,5,8,12,
lf_country%mask_val_min = 100,
lf_country%mask_val_max = 357,
lf_country%sector_list(1:1)=0, ! sum of all sectors
lf_country%cellmask_name(1:1) = 'municip_mask',
lf_src(1)%species="pm25",
lf_src(1)%type='country',
mask2name(1)='Oslo', !map id numbers to names (for use in output)
mask2name(2)='Eigersund',
If a value is within the min and max range, but does not appear in the mask file, it will not be taken into account (meaning it is ok to specify a range that covers all the masks values, even if some values are not defined on the mask)
(under development): use mask file with fraction of emissions in each gridcell:
EmisMask(1)%filename = '/ec/res4/hpcperm/fan/Data/Masks/cameo_city_masks.nc',
EmisMask(1)%cdfname = 'TouHan',
EmisMask(1)%type = 'CELL-FRACTION',
EmisMask(1)%ID = 'ToHa',
EmisMask(2)%filename = '/ec/res4/hpcperm/fan/Data/Masks/cameo_city_masks.nc',
EmisMask(2)%cdfname = 'PorUtr',
EmisMask(2)%type = 'CELL-FRACTION',
EmisMask(2)%ID = 'PoUt',
lf_country%cellmask_name(1) = 'ToHa',
In this example two masks are defined (those can be used for traditional SR runs too), and only the mask with name “PoUt” is used as a “country” in the LF run.
Local Fractions for Sensibilities with full chemistry¶
The full chemistry can be included. This option is under development, and only limited options are available. The cpu cost is high, approximatively 20 times the cost without this option (independently of the number of sources tracked). To use this option the fortran code must be prepared with the script utils/mk.LF_Chem. Example of config settings:
USES%LocalFractions = T, ! T for computing Local Fractions
lf_set%YEAR = T, !average value for full run in output
lf_set%Nvert = 14, !How many vertical level to include in treatment. Should be higher than highest emissions
lf_set%full_chem = T, ! to indicate that all species must be included
lf_set%EmisDer_all = T, ! reduce voc, sox, nox, nh3 together (separately if F)
! Specify which countries and sectors
lf_country%sector_list(1:)=0,1,8,
lf_country%list(1:20)='FR','IT','DE','ES','NO','NL','SE','PL','AT','BE','BG','DK','FI','GR','HU','PT','RO','CH','TR','GB',
lf_country%group(1)%name='NORDIC', !any name given to the group (used as output name)
lf_country%group(1)%list(1:)='NO','DK','SE','FI', ! countries included in the group
! Specify which species or group of species must be outputted
lf_spec_out(1)%name='O3', !single species
lf_spec_out(2)%name='NO', !single species
lf_spec_out(3)%name='NO2', !single species
lf_spec_out(4)%name='SIA',!group of species
lf_spec_out(4)%species(1:)='SO4','NO3_f','NO3_c','NH4_f', !species to include in the group
lf_spec_out(4)%species_fac(1:)=1.0, 1.0, 1.0, 1.0, !weights (default 1.0)
lf_spec_out(5)%name='NOx',!group of species
lf_spec_out(5)%species(1:)='NO','NO2', !species to include in the group
lf_set%MDA8 = T, !special: make AvgMDA8_6month. NB: requires that O3 is outputted too
Technical¶
Time steps¶
There are three types of timesteps in the model: METSTEP, dt_advec and dtchem.
METSTEP is the time interval between two readings of the meteorological file. It is not set by the user, but uses whatever is used as meteorological input. It must be a divisor of 24 hours. Three hours is standard, but other intervals are used too.
dt_advec is the “time splitting” interval, i.e. the time between two sequences of advection-chemsitry/emissions-deposition. (Note that the name is misleading, the advection can have a smaller internal timestep if it is requird by the Courant number). The value of dt_advec must be an entire fraction of one hour (units seconds). It is determined by the model using the grid resolution. For a grid resolution larger than 61 km it is 1800s, or 1200s if larger than 21km, or 900s if larger than 11km, or 600s if larger than 6km, or 300s if larger than 2km or 100s if smaller than 2km. Those value can be overriden by defining it in config_emep.nml. You can check the value in the standard output (“advection time step (dt_advec) set to: 1200 seconds”).
The values of dtchem are the internal Chemistry timesteps. It is variable: usually the first 5 steps last 20 seconds, then followed by 10 larger timesteps, so that the sum of all dtchem timesteps is exactly equal to dt_advec. They are printed out in standard output. Note that emissions are included as a source in the Chemistry, and thus have the same timesteps.