Product user manual for the TM5 NO2, SO2 and HCHO profile auxiliary support product
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Product user manual for the TM5 NO2, SO2 and HCHO profile auxiliary support product document number : S5P-KNMI-L2-0035-MA authors : Henk Eskes and Jos van Geffen CI identification : None issue : 1.0.0 date : 2021-02-04 status : released
PUM TM5 AUX Product S5P-KNMI-L2-0035-MA issue 1.0.0, 2021-02-04 – released Page 2 of 19 Document approval record This document was prepared by Henk Eskes and Jos van Geffen. It was checked by Maarten Sneep and Pepijn Veefkind.
PUM TM5 AUX Product S5P-KNMI-L2-0035-MA issue 1.0.0, 2021-02-04 – released Page 3 of 19 Document change record issue date item comments 0.0.1 2020-09-08 All Initial template 0.1.0 2021-01-27 All First draft 0.2.0 2021-02-02 All Added section 4.4 1.0.0 2021-02-04 All Prepared for release
PUM TM5 AUX Product S5P-KNMI-L2-0035-MA issue 1.0.0, 2021-02-04 – released Page 4 of 19 Contents Document approval record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Document change record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.1 Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2 Purpose and objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.3 Document overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 Applicable and reference documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.1 Applicable documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.2 Standard documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.3 Reference documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.4 Electronic references . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3 Terms, definitions and abbreviated terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.1 Acronyms and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 High level description of the TM5-MP auxiliary product . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2 File names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.2.1 Obtaining data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.3 File content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5 Python tool to extract TM5-MP profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.1 Extract the profile for a single time and location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.2 Extract profiles for a Level-2 file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6 Description of the TM5-MP auxiliary product . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 List of Tables 1 Content of the auxiliary support output file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 List of Figures 1 Processing flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
PUM TM5 AUX Product S5P-KNMI-L2-0035-MA issue 1.0.0, 2021-02-04 – released Page 5 of 19 1 Introduction 1.1 Identification This document is identified as S5P-KNMI-L2-0035-MA. 1.2 Purpose and objective This document describes the CTMFCT and CTMANA auxiliary support products, produced with the TM5-MP chemistry-transport model. 1.3 Document overview The following section lists the reference documents and electronic references. Section 3 contains the relevant terms, definitions and abbreviations. Section 4 is the core of this document and describes the auxiliary support product. This is followed by section 5 where the python tool to extract profiles described. Finally in section 6 a detailed listing of attributes and fields in the NetCDF-4 files is given.
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2 Applicable and reference documents
2.1 Applicable documents
There are no applicable documents
2.2 Standard documents
There are no standard documents
2.3 Reference documents
[RD1] Terms, definitions and abbreviations for TROPOMI L01b data processor.
source: KNMI; ref: S5P-KNMI-L01B-0004-LI; issue: 3.0.0; date: 2013-11-08.
[RD2] Terms and symbols in the TROPOMI Algorithm Team.
source: KNMI; ref: S5P-KNMI-L2-0049-MA; issue: 2.0.0; date: 2016-05-17.
2.4 Electronic references
[ER1] TROPOMI level-2 product ATBD documents. URL http://www.tropomi.eu/documents/atbd/.
[ER2] TROPOMI level-2 product PUM documents. URL http://www.tropomi.eu/documents/pum/.
[ER3] Sentinel-5P Pre-Operations Data Hub. URL https://s5phub.copernicus.eu/.
[ER4] Sentinel-5P Expert Data Hub. For authorised users only; URL https://s5pexp.copernicus.eu/.PUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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3 Terms, definitions and abbreviated terms
Terms, definitions and abbreviated terms that are used in development program for the TROPOMI L0-1B data
processor are described in [RD1]. Terms, definitions and abbreviated terms for the Level 2 algorithms are
described in [RD2]. Terms, definitions and abbreviated terms that are specific for this document can be found
below.
The most important symbols related to the data product described in this document – some of which are
not in [RD2] – are listed in table 1.
3.1 Acronyms and Abbreviations
ATBD Algorithm theoretical basis document
ECMWF European Centre for Medium-Range Weather Forecasts
IFS Integrated Forecast System of the ECMWF
NRTI Near-real time retrieval processing or near-real time retrieval product
OFFL Offline retrieval processing or offline retrieval product
S5P Sentinel-5P
TM5-MP Tracer Model version 5, massively parallel versionPUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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4 High level description of the TM5-MP auxiliary product
The TM5-MP auxiliary product contains one day of 3D model fields of NO2 , HCHO and SO2 , with a time step of
30 minutes, as well as the 3D model temperature field. These fields have been used to extract a-priori profile
shapes for the NO2 , HCHO and SO2 vertical column retrievals.
For the advanced users a Python tool is made available to use these 3D model NO2 trace gas data files
to add interpolated a-priori profiles to the L2 NO2 retrieval files S5P_OFFL_L2__NO2, or to extract individual
profiles. This tool is described in section 5
4.1 Introduction
Figure 1: Overview of the processing blocks in the offline retrieval of NO2 . The S5P_OPER_AUX_CTMANA files
are indicated in yellow.
The Sentinel-5P TROPOMI operational retrievals of NO2 , SO2 and HCHO are described in detail in the ATBDs
for these products [ER1] and the corresponding product user manuals [ER2].
Figure 1 shows a simplified block diagram of the offline (OFFL) retrieval of NO2 for TROPOMI. A similar,
but slightly more complex diagram can be drawn for the near-real time (NRTI) retrieval step. More details can
be found in the ATBD [ER1]. As shown in this diagram, daily runs of the TM5-MP model are fully integrated in
the retrieval. For OFFL the processing starts with the DOAS spectral fits and derivation of the slant columns
(red box). These are stored in preliminary NO2 L2 files and read by the TM5-MP chemistry-transport model.
The air-mass factors, averaging kernels and vertical columns are computed in a retrieval module which is
part of TM5-MP, using the model fields co-located in space and time to the measurement time and footprint.
After the retrieval step the NO2 total slant columns are assimilated in TM5-MP. The result of this step is a
stratospheric column which is in good agreement with the TROPOMI data. In the OFFL processing this is
followed by a short-range forecast of the atmospheric chemical state, until the time of the next orbit, after which
the retrieval and assimilation steps are repeated. For the OFFL processing, TM5-MP is run for a period of one
day, and restart files are passed on to the next day. During the run, the trace gas results are stored in the
S5P_OPER_AUX_CTMANA files.
In the NRTI case, the TM5-MP daily analysis run is extended with a 3-day forecast run, resulting in four
S5P_OPER_AUX_CTMFCT files each covering a period of 24 hours. These files are used as input for the
NRTI retrieval processors to extract the a-priori profiles on NO2 , SO2 and HCHO used in the air-mass factor
calculation. Apart from a different forecast lead time, resulting in some changes in the trace gas concentrations,
the contents of the S5P_OPER_AUX_CTMFCT and S5P_OPER_AUX_CTMANA files are the same.
The S5P_OPER_AUX_CTMFCT and S5P_OPER_AUX_CTMANA files serve several purposes:
1. Provide a-priori profile shapes for the near-real time and off-line retrievals of NO2 , HCHO and SO2 . The
files contain 3D tracer fields with a 30 minutes time step, simulated with the TM5-MP chemistry-transport
model. In the operational L2 retrieval processors these files are used as input to derive space and time
co-located trace gas profile shapes for each of the individual TROPOMI observations. These profiles are
used to compute the air-mass factors and retrieved vertical column amounts.
2. Provide across-track stripe amplitudes to the near-real time NO2 processor.PUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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3. Provide advanced users with the a-priori model input.
As described in the NO2 product user manual, the L2 files contain all the information needed to replace the
TM5-MP a-priori profile (and influence on the vertical column) by profiles from an other model. This is useful
especially when a regional chemistry transport model is used with much higher spatial resolution than TM5-MP.
Such a replacement will generally lead to more (more realistic) contrast between hotspots and surrounding
rural areas.
For some applications, such as detailed validation studies or comparisons, the a-priori profiles are of
interest. For such applications the CTMFCT files and the Python tool to extract profiles are of use. These are
described below.
4.2 File names
The support product is stored in NetCDF-4 files, with file names like:
S5P_OPER_AUX_CTMFCT_20190510T000000_20190511T000000_20190511T041957.nc
S5P_OPER_AUX_CTMANA_20190605T000000_20190606T000000_20190617T123921.nc
The CTMFCT files are resulting from forecast runs of the TM5-MP model produced once per day. Each file
contains 24 hours, and the files cover the day before the forecast is produced (yesterday) up to 3 days in the
future. In total 4 CTMFCT are available for each day of processing. These files are used for the near-real time
processors of NO2 , HCHO and SO2 . The model runs make use of the 5-day meteorological forecasts of the
ECMWF IFS model produced from the 12 UTC analyses.
The CTMANA files are produced during the off-line processing. In this case only one file with 24 hours of
CTM output is available for each day of processing. These files are used for offline processing and reprocessing.
The model runs used to produce these files make use of short-range 0 to 12 hour forecasts of the ECMWF IFS
model.
The second part of the file name consists of three time fields "yyyymmddThhmmss". The first and second
time field specify the start and end time of 24 hour time range covered by the 3D trace gas and temperature fields
in the file. Each file covers 24 hours, with 48 3-dimensional trace gas and temperature fields corresponding to
the 30-minute time step. The third time field specifies the time the file was produced (UTC).
4.2.1 Obtaining data
The files are available from the same data hub where NO2 , SO2 and HCHO level 2 data can be obtained [ER3].
In the past these files were only available for authorised users through the expert hub [ER4], but this is meant
to change. Depending on timing the data may not yet be available on the public data hub.
4.3 File content
The arrays included in the file are specified in table 1. The more detailed description of data fields and attributes
is provided in section 6. Here we discuss the content by referring to the names in the NetCDF-4 files:
no2, ch2o, so2 The 3-D model fields of NO2 , HCHO and SO2 , stored as grid-cell mean volume mixing ratio
with a time step of 30 minutes. These are 4-dimensional arrays.
t The temperature field, also a 4-dimensional array. They originate from the ECMWF IFS daily forecasts,
interpolated to the TM5-MP grid with 1x1 degree horizontal grid cells.
hyai, hybi, hyam, hybm Static hybrid coefficients for the interfaces "i" and mid-layer "m" pressure levels. In
order to reconstruct the vertical pressure levels these have to be combined with the time-dependent
surface pressure, see below.
ps Surface pressure, a 3-dimensional array (time dependent).
surface_altitude The ECMWF elevation map interpolated to the 1x1 degree TM5-MP model grid cells.
tropopause_layer_index The TM5-MP model layer index which contains the tropopause level, a 3-dimensional
fieldPUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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Table 1: Overview of the data set units, types and sizes in the support output product file. This file is used
to store the profiles of NO2 , HCHO and SO2 , delivered by the TM5-MP model. The data is provided on the
TM5-MP grid resolution of 1◦ × 1◦ on a half-hourly basis.
quantity field name symbol unit comment type #‡ note
HCHO profile ch2o nl,HCHO 1 volume mixing ratio float nl †
NO2 profile no2 nl,NO2 1 volume mixing ratio float nl †
SO2 profile so2 nl,SO2 1 volume mixing ratio float nl †
TM5 temperature profile t TlTM5 K — float nl †
TM5 level coefficients, interface hyai ATM5
l Pa — float 0 ¶
hybi BTM5
l 1 — float 0 ¶
TM5 level coefficients, layer hyam — Pa — float 0
hybm — 1 — float 0
TM5 surface elevation surface_altitude zTM5
s m — float 1 —
TM5 surface pressure ps pTM5
s Pa — float 1 —
TM5
TM5 tropopause layer index tropopause_layer_index ltp 1 — int 1 —
stripe amplitude nitrogendioxide_slant_ str
Ns,NO mol/m2 NO2 SCD float 0 ⊗
2
column_density_ stripe amplitude
stripe_amplitude
longitude lon — degree degrees east, model grid float 0
latitude lat — degree degrees north, model grid float 0
level lev — 1 level index, model grid float 0
date & time date — 1 year, month, day, int 0 §
1 hour, min, sec
day index time d days days since 1 Jan. 1950 float 0 §
‡ The number of elements for each horizontal (x,y) model grid cell.
† The number of TM5 layers is nl = 34.
¶ The n + 1 (see note †) TM5-MP vertical pressure level coefficients at layer interfaces.
l
The nl (see note †) TM5-MP vertical pressure level coefficients at layer midpoints.
§ One set per data file.
⊗ One set per detector row.
nitrogendioxide_slant_column_density_stripe_amplitude Used in the NO2 retrieval to correct the slant
columns for viewing-angle dependent retrieval offsets. The array has a fixed dimension equal to the
number of ground pixels per TROPOMI observation (450) and varies from day to day.
lon, lat Longitudes and latitudes of the TM5-MP model (1-dimensional, fixed)
lev Layer index, to be used in the computation of the pressure.
date Date and time
time Time expressed as one number, to be interpreted as the (fractional) number of days since 1 January
1950.
Note that the model divides the atmosphere in nl layers. The pressure level coefficients determine the pressure
at the nl + 1 levels separating the layers: pl = ATM5
l + BTM5
l · ps , for l = 0, 1, . . . , nl , with ps the surface pressure
for the given TROPOMI ground pixel. The pressure for the layer l , for which the concentration (volume mixing
ratio) nl,NO2 and the temperature TlTM5 are given, is then midway between the level pressures pTM5 l−1 and pl
TM5
.
TM5
The layer with index ltp contains the tropopause.PUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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5 Python tool to extract TM5-MP profiles
The Python tool TM5_profile.py can be used to extract trace gas (NO2 , SO2 or formaldehyde) profiles from
a TM5-MP made CTM auxiliary file. The general usage of the tool is as follows:
TM5_profile.py [-h] [--version] [-v] [-s MOLECULE] -c CTM [-V]
{single,level2} ...
where the positional argument determines the mode of usage, discussed in more detail in the following
subsections:
single Extract the profile for a single time and location.
level2 Extract profiles for a Level-2 file; the profiles will be added to the file.
The positional argument is preceeded by some general optional arguments:
-h, --help show this help message and exit
--version show version info and exit
-v, --verbose be chatty
-s MOLECULE, --species MOLECULE
trace gas for which to extract the profile, default:
NO2; valid arguments: NO2, SO2, HCHO, CH2O
-c CTM, --ctm CTM the CTM file with the profiles
-V, --vmr store the profile as vmr rather than partial columns
The latest version of the script can be downloaded via (see also the -h option):
http://www.tropomi.eu/data-products/nitrogen-dioxide/
5.1 Extract the profile for a single time and location
In the single mode, the tool extracts the trace gas and the temperature profile for a single location and
moment in time, and writes the profiles to screen.
Arguments controling this mode are given after the positional argument single mentioned above:
TM5_profile.py single [-h] -t YYYY-MM-DDTHH:MM:SS (-g L L | -G NAME)
[-p PRESSURE]
The location can be specified by a coordinate or by one of the in the script pre-set names; the user can easily
extend that list, which is near the top of the script1 .
Details of the arguments are as follows:
-h, --help show this help message and exit
-t YYYY-MM-DDTHH:MM:SS, --time YYYY-MM-DDTHH:MM:SS
date and time to extract the profile for
-g L L, --geo-point L L
location to extract the profile for as a LAT LON pair
-G NAME, --geo-name NAME
location to extract a profile for by name; recognized
names are: ’BIRA’, ’Cabauw’, ’DLR’, ’ESRIN’, ’ESTEC’,
’FMI’, ’GSFC’, ’IUP’, ’Jungfraujoch’, ’KNMI’, ’MPI’,
’Paramaribo’, ’RAL’, ’Sodankyla’, ’Xianghe’.
-p PRESSURE, --pressure PRESSURE
surface pressure in hPa to use for the profile; if not
given the TM5 surface pressure is used
Example usage extracting an NO2 profile from ctmfile with a coordinate:
TM5_profile.py -c ctmfile -s no2 single -t 2020-09-01T12:00:00 -g 31.9 118.9
The temperature and trace gas profile are given per layer and for each layer the bottom, top and mid pressure
are listed. The five header lines further list the units, the time and location, the CTM file, as well as the pressure
of the tropopause:
1
Send us your additions and we will add them to the next release of the script.PUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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pressure_bottom pressure_top pressure_mid temperature no2_partial_columns
# hPa # hPa # hPa # K # mol/m2 in layer
# time: 2020-09-01T12:00:00Z, latitude: 31.9, longitude: 118.9
# source: S5P_OPER_AUX_CTMANA_20200901T000000_20200902T000000_20200910T124051.nc
# tropopause pressure: 73.11869140625 hPa
1002.005 994.201328125 998.103125 300.15118408203125 4.154561611358076e-05
994.201328125 975.701015625 984.95109375 299.62860107421875 5.8249555877409875e-05
975.701015625 947.624921875 961.66296875 298.218505859375 3.0179839086486027e-05
...
In this example the profile is given as partial columns. If the main argument -V is used, the profile is given as
volume mixing ratios (vmr):
pressure_bottom pressure_top pressure_mid temperature no2_vmr
# hPa # hPa # hPa # K # 1
...
5.2 Extract profiles for a Level-2 file
In the level2 mode, the tool extracts the trace gas (and optionally the temperature) profiles for all ground
pixels in a Level-2 file, and adds the profiles to the Level-2 file (this mode requires read/write access of the
Level-2 file).
Arguments controling this mode are given after the positional argument level2 mentioned above:
TM5_profile.py level2 [-h] -i L2_FILE [--use-TM5-pressure]
[--add-temperature-profile]
Details of the arguments are as follows:
-h, --help show this help message and exit
-i L2_FILE, --input L2_FILE
level-2 file to add the profile data to
--use-TM5-pressure use the surface pressure from TM5 rather than the
surface pressure given in the level-2 file
--add-temperature-profile
also add the temperature profile from TM5 to the
level-2 file
Example usage adding NO2 and temperature profiles from ctmfile to l2file:
TM5_profile.py -c ctmfile -s no2 level2 -i l2file
TM5_profile.py -c ctmfile -s no2 -V level2 -i l2file
TM5_profile.py -c ctmfile -s no2 level2 -i l2file --add-temperature-profile
These add the data variable no2_partial_columns or no2_vmr and optionally temperature to the group
PRODUCT/SUPPORT_DATA/DETAILED_RESULTS.PUM TM5 AUX Product S5P-KNMI-L2-0035-MA issue 1.0.0, 2021-02-04 – released Page 13 of 19 6 Description of the TM5-MP auxiliary product Global attributes in S5P_OPER_AUX_CTMFCT Group attributes attached to S5P_OPER_AUX_CTMFCT Name Value Type Conventions ‘CF-1.6’ (static) NC_STRING Conventions that apply to the dataset. validity_start ‘YYYYmmddTHHMMSS’ (dynamic) NC_STRING Start of the coverage of the data in this file in UTC. validity_stop ‘YYYYmmddTHHMMSS’ (dynamic) NC_STRING End of the coverage of the data in this file in UTC. creation_date ‘YYYYmmddTHHMMSS’ (dynamic) NC_STRING Date and time of production of this dataset. version ‘mp 1 beta (benchmark)’ (dynamic) NC_STRING Version string of the TM5 model. institution ‘KNMI, Netherlands’ (dynamic) NC_STRING Originating institute. reference ‘Huijnen et al., doi:10.5194/gmdd-3-1009-2010’ (static) NC_STRING Reference for the TM5 model. contact ‘eskes@knmi.nl’ (dynamic) NC_STRING Point of contact for this dataset. dataset_name ‘S5P_OPER_AUX_CTMFCT’ (dynamic) NC_STRING Name of the dataset, forecast or analysis. Possible values: S5P_OPER_AUX_CTMFCT, S5P_OPER_AUX_CTMANA title ‘mixing ratios & concentrations’ (static) NC_STRING Title of the dataset. dataset_version ‘mp 1 beta (benchmark)’ (dynamic) NC_STRING Dataset version file_version_number ‘0.1’ (dynamic) NC_STRING File version number im 360 (dynamic) NC_INT Number of model longitudes jm 180 (dynamic) NC_INT Number of model latitudes lm 34 (dynamic) NC_INT Number of model layers dx 1. (dynamic) NC_DOUBLE Longitude step dy 1. (dynamic) NC_DOUBLE Latitude step dz 1. (dynamic) NC_DOUBLE Level step xbeg -180 (dynamic) NC_INT Longitude range, low value xend 180 (dynamic) NC_INT
PUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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Longitude range, high value
ybeg -90 (dynamic) NC_INT
Latitude range, low value
yend 90 (dynamic) NC_INT
Latitude range, high value
zbeg 0 (dynamic) NC_INT
Level range, low value
zend 34 (dynamic) NC_INT
Level range, high value
meteo_model ‘forecast (IFS)’ (dynamic) NC_STRING
Soure of meteorological forecasts
Possible values: forecast (IFS)
history ‘Created 2020-07-23 05:16:00 +0000 by Henk Eskes NC_STRING
with TM5.’ (dynamic)
Provides an audit trail for modifications to the original data. Well-behaved generic netCDF filters will
automatically append their name and the parameters with which they were invoked to the global history
attribute of an input netCDF file. Each line shall begin with a timestamp indicating the date and time of day
that the program was executed.
Dimensions in S5P_OPER_AUX_CTMFCT
nGroundPixels Number of ground pixels of TROPOMI
size 450 (dynamic)
source Processor.
lon Number of longitudes
size 360 (dynamic)
source Processor.
lat Number of latitudes
size 180 (dynamic)
source Processor.
lev Number of layers
size 34 (dynamic)
source Processor.
levi Number of levels, layer interfaces
size 35 (dynamic)
source Processor.
time Number of times
size 48 (dynamic)
source Processor.
datelen Length of the date array
size 6 (fixed)
source Processor.
Variables in S5P_OPER_AUX_CTMFCTPUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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lon in S5P_OPER_AUX_CTMFCT
Description: Array of longitudes
Dimensions: lon (coordinate variable).
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘longitude’ (static) NC_STRING
Standard name
long_name ‘longitude’ (static) NC_STRING
Long name
units ‘degrees_east’ (static) NC_STRING
Units
lat in S5P_OPER_AUX_CTMFCT
Description: Array of latitudes
Dimensions: lat (coordinate variable).
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘latitude’ (static) NC_STRING
Standard name
long_name ‘latitude’ (static) NC_STRING
Long name
units ‘degrees_north’ (static) NC_STRING
Units
hyai in S5P_OPER_AUX_CTMFCT
Description: Hybrid level coefficient A, interfaces
Dimensions: levi.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
units ‘Pa’ (static) NC_STRING
Units
long_name ‘hybrid A coefficient at layer interfaces’ (static) NC_STRING
Long name
hybi in S5P_OPER_AUX_CTMFCT
Description: Hybrid level coefficient B, interfaces
Dimensions: levi.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
units ‘1’ (static) NC_STRING
Units
long_name ‘hybrid B coefficient at layer interfaces’ (static) NC_STRING
Long name
hyam in S5P_OPER_AUX_CTMFCT
Description: Hybrid level coefficient A, mid-layer
Dimensions: lev.PUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
units ‘Pa’ (static) NC_STRING
Units
long_name ‘hybrid A coefficient at layer midpoints’ (static) NC_STRING
Long name
hybm in S5P_OPER_AUX_CTMFCT
Description: Hybrid level coefficient B, mid-layer
Dimensions: lev.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
units ‘1’ (static) NC_STRING
Units
long_name ‘hybrid B coefficient at layer midpoints’ (static) NC_STRING
Long name
lev in S5P_OPER_AUX_CTMFCT
Description: Model layer index
Dimensions: lev (coordinate variable).
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘atmosphere_hybrid_sigma_pressure_coordinate’ NC_STRING
(static)
Standard name
long_name ‘hybrid level at layer midpoints’ (static) NC_STRING
Long name
units ‘level’ (static) NC_STRING
Units
positive ‘down’ (static) NC_STRING
Order of layering, decreasing or increasing
formula ‘hyam hybm (mlev=hyam+hybm*ps)’ (static) NC_STRING
Formula to compute the pressures
formula_terms ‘ap: hyam b: hybm ps: ps’ (static) NC_STRING
Formula terms
time in S5P_OPER_AUX_CTMFCT
Description: Time as one fractional number, days since 1950
Dimensions: time (coordinate variable).
Type: NC_DOUBLE.
Source: Processor.
Attributes: Name Value Type
standard_name ‘time’ (static) NC_STRING
Standard name
long_name ‘time’ (static) NC_STRING
Long name
units ‘days since 1950-01-01 00:00:00’ (static) NC_STRINGPUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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Units
calender ‘gregorian’ (static) NC_STRING
Calendar
date in S5P_OPER_AUX_CTMFCT
Description: Date and time as 6-integer array
Dimensions: time, datelen.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
long_name ‘date and time’ (static) NC_STRING
Long name
units ‘year, month, day, hour, minute, second’ (static) NC_STRING
Units
ps in S5P_OPER_AUX_CTMFCT
Description: Surface pressure
Dimensions: time, lat, lon.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘surface_air_pressure’ (static) NC_STRING
Standard name
long_name ‘surface pressure’ (static) NC_STRING
Long name
units ‘Pa’ (static) NC_STRING
Units
surface_altitude in S5P_OPER_AUX_CTMFCT
Description: Surface altitude
Dimensions: lat, lon.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘surface_altitude’ (static) NC_STRING
Standard name
long_name ‘surface altitude of TM5 grid’ (static) NC_STRING
Long name
units ‘m’ (static) NC_STRING
Units
comment ‘ECMWF interpolated orography’ (static) NC_STRING
Comment
nitrogendioxide_slant_column_density_stripe_amplitude in S5P_OPER_AUX_CTMFCT
Description: NO2 slant column stripe amplitude. This is used in the near real time processing of NO2 to
perform a destriping of the signal. Details are provided in the ATBD.
Dimensions: nGroundPixels.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
long_name ‘Across-track NO2 slant column stripe offset, 7-day NC_STRING
mean, determined over the Pacific Ocean’ (static)PUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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Long name
units ‘mol m-2’ (static) NC_STRING
Units
multiplication_- 6.02214e+19f (static) NC_FLOAT
factor_to_con-
vert_to_mo-
lecules_percm2
Multiplication factor to convert to molecules per cm2
_FillValue 9.96921e+36f (static) NC_FLOAT
The fill value or undefined value
comment ‘The stripe amplitude is subtracted from the NO2 NC_STRING
slant column before the vertical columns are com-
puted’ (static)
Comment
tropopause_layer_index in S5P_OPER_AUX_CTMFCT
Description: Tropopause layer index
Dimensions: time, lat, lon.
Type: NC_INT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘tropopause_layer_index’ (static) NC_STRING
Standard name
long_name ‘index of the highest model layer in the troposphere’ NC_STRING
(static)
Long name
units ‘-’ (static) NC_STRING
Units
comment ‘Based on WMO temperature gradient method’ NC_STRING
(static)
Comment
so2 in S5P_OPER_AUX_CTMFCT
Description: Sulphur dioxide volume mixing ratio
Dimensions: time, lev, lat, lon.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘mole_fraction_of_sulfur_dioxide_in_air’ (static) NC_STRING
Standard name
long_name ‘volume mixing ratio of SO2 in humid air’ (static) NC_STRING
Long name
units ‘1’ (static) NC_STRING
Units
moleweight_- 64062.8 (static) NC_DOUBLE
tracer
Mole weight
moleweight_air 28940. (static) NC_DOUBLE
Mole weight air
moleweight_unit ‘kg mole-1’ (static) NC_STRINGPUM TM5 AUX Product S5P-KNMI-L2-0035-MA
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Mole weight units
no2 in S5P_OPER_AUX_CTMFCT
Description: Nitrogen dioxide volume mixing ratio
Dimensions: time, lev, lat, lon.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘mole_fraction_of_nitrogen_dioxide_in_air’ (static) NC_STRING
Standard name
long_name ‘volume mixing ratio of NO2 in humid air’ (static) NC_STRING
Long name
units ‘1’ (static) NC_STRING
Units
moleweight_- 46005.5 (static) NC_DOUBLE
tracer
Mole weight
moleweight_air 28940. (static) NC_DOUBLE
Mole weight air
moleweight_unit ‘kg mole-1’ (static) NC_STRING
Mole weight units
ch2o in S5P_OPER_AUX_CTMFCT
Description: Formaldehyde volume mixing ratio
Dimensions: time, lev, lat, lon.
Type: NC_FLOAT.
Source: Processor.
Attributes: Name Value Type
standard_name ‘mole_fraction_of_formaldehyde_in_air’ (static) NC_STRING
Standard name
long_name ‘volume mixing ratio of CH2O in humid air’ (static) NC_STRING
Long name
units ‘1’ (static) NC_STRING
Units
moleweight_- 30026.35 (static) NC_DOUBLE
tracer
Mole weight
moleweight_air 28940. (static) NC_DOUBLE
Mole weight air
moleweight_unit ‘kg mole-1’ (static) NC_STRING
Mole weight unitsYou can also read
