S5P Mission Performance Centre
Aerosol Layer Height [L2__AER_LH]
Readmedocument number
issue
date
product version
status

S5P-MPC-KNMI-PRF-AER_LH

Prepared by

M. de Graaf (KNMI)-

MPC Product Lead
MPC Validation Coordinator

J.-C. Lambert (BIRA-IASB)
D. Loyola (DLR)
D. Stein Zweers (KNMI)
A. Dehn (ESA)
C. Zehner (ESA)MPC ESL-VAL Lead
MPC ESL-L2 Lead
MPC Technical Manager
ESA Data Quality Manager
ESA Mission Manager

Reviewed byApproved by

2.4
2023-03-15
V02.05.00
Released

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MPC Contributors

M. Sneep (KNMI)
S. Nanda (KNMI)
L. Saavedra de Miguel (ESA/Serco)

MPC ESL-L2 Product Contributor
MPC ESL-L2 Product Contributor
ESA S5p Mission Support

S5PVT1
Contributors

S Kondragunta (NOAA)
N. O'Neill (Université de Sherbrooke)

S5P Validation Team PI
S5P Validation Team PI

signedAngelika Digitallyby Angelika Dehn
Date: 2023.03.16
Dehn
15:05:16 +01'00'
Signatures

Angelika Dehn (ESA), Data Quality Manager

Claus
ZehnerDigitally signedby Claus Zehner
Date: 2023.03.16
16:17:27 +01'00'

Claus Zehner (ESA), Sentinel-5 Precursor Mission
Manager

1

The S5PVT AO project summaries can be found athttps://earth.esa.int/eogateway/news/announcement-of-opportunity-for-s5pvt

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Reason for change

Cloud mask is based on VIIRS ECM product (instead for VICMO) since
OFFL orbit 12432 (see section 4.2)
Table 2: addition of version 01.04.00• Table 2: Adapting to V02.02.00 of the processor.
• Section 3.2: Validation results shortened, pointing to the routine
Validation reports.
• Section 4.1 & section 4.2: some text moved from section 4.1(Known Data Quality Issues) to section 4.2 (Solved Data Quality
Issues).
• Section 6.1: added format changes related to version 02.02.00.
• Table 2: addition of version 02.03.01• Section 4.1: Added ‘Data in snow_ice_flag variable for pixels
with SZA > 88o• Section 4.2: Added ‘Geolocation co-added when they should not
be (solved in 02.03.01)’• Table 2: addition of version 02.04.00.
• Section 4.1 & section 4.2: some text moved from section 4.1(Known Data Quality Issues) to section 4.2 (Solved Data Quality
Issues).
• Section 5: Added radiometric calibration of L1B and new LER
surface database information.
• Table 2: addition of reprocessed dataset with version 02.04.00• Section 7: updates with information related to gaps on the
reprocessed dataset• Table 2: addition of version 02.05.00• Section 6.1: added minor format changes related to version
02.05.00

Issue Revision

Date

1

2

11/03/2020

1

3

02/12/2020

2

0

05/07/2021

2

1

17/11/2021

2

2

20/07/2022

2

3

22/02/2023

2

4

15/03/2023

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SummaryThis is the Product Readme file (PRF) for the Copernicus Sentinel 5 Precursor Tropospheric Monitoring
Instrument (S5P/TROPOMI) Aerosol Layer Height (L2__AER_LH) Level 2 product and is applicable for
the Near Real-Time (NRTI), Offline (OFFL) and Reprocessed (RPRO) timeliness data products.
Product Identifier: L2__AER_LH
Example filename:
S5P_OFFL_L2__AER_LH_20210908T001010_20210908T015140_20226_02_020200_20210909T165109.nc
S5P_NRTI_L2__AER_LH_20210908T002709_20210908T003209_20226_02_020200_20210908T013221.nc
S5P_RPRO_L2__AER_LH_20180501T165554_20180501T183724_02842_03_020400_20221125T084824.nc

The OFFL and RPRO data products have the following Digital Object Identifier (DOI):
http://doi.org/10.5270/S5P-7g4iapn
The Readme file describes the current processing baseline, product and quality limitations, and productavailability status. More information on this data product is available from the Sentinel product webpage:https://sentinels.copernicus.eu/web/sentinel/technical-guides/sentinel-5p/products-algorithms,
and from the TROPOMI product webpage http://www.tropomi.eu/data-products.
The data file contains the aerosol_mid_pressure and aerosol_mid_height which provide theair pressure at the center of the aerosol layer and the height at the center of the aerosol layer relative
to the geoid, respectively. The aerosol layer mid pressure is computed for pixels that are free of ice,
snow, and clouds. The maximum allowed cloud fraction is 2%, except if the UVAI is larger than 1.0,
those pixels are always processed. The latter is to avoid volcanic ash and dust plumes mistakenly being
filtered as clouds. As a user guideline, it is recommended to use only those pixels that contain nosunglint. The sun_glint_warning flag is available to filter those ALH pixels that are possibly sunglint
contaminated. In general, the data quality is indicated by a qa_value. Pixels with a qa_value below
0.5 are not recommended for use.
Note: Starting from this processor version 2.4.0, new improved Level 1b version 2.1 data products areused as input [RD04].
The TROPOMI L2__AER_LH product is a relatively new product, released in September 2019, with little
heritage. Aerosol vertical profile products exist from other satellite instruments, e.g., active
measurements from Caliop onboard CALIPSO, and multi-angle measurements from MISR onboard
Terra.
First validation efforts by Sentinel-5 Precursor (S5p) Mission Performance Centre (MPC) Cal/Val experts
and the S5p Validation Team (S5PVT) show that the ALH is stable and shows good overall agreementwith Caliop retrievals, with Caliop generally retrieving higher ALH than TROPOMI for ocean scenes. A
statistical pixel-by-pixel comparison of Caliop and S5P layer height retrievals from three desert dust
cases and one smoke plume showed good correlation between the retrievals (regression slope 1.00),
but on average Caliop retrievals were 0.53 km higher in altitude than S5P ALH. This is likely due to thedifferent sensitivity, which for Caliop is to the top of the plume, while S5P is sensitive to the centroid of
the layer altitude. This was confirmed by a study which compared smoke plumes heights over Canada
from S5P and those retrieved by Caliop and MISR. The latter uses stereoscopic viewing to retrieve
plume top height. The systematic difference between S5P TROPOMI ALH and MISR aerosol plumeheight is about 600 m. This is again due to differences in the sensitivity of the instruments and thedifferences in the algorithms (centroid vs. top retrieval).
Over land, TROPOMI ALH becomes unreliable for increasing surface albedo. Consequently, thedifference between the plume height observed by TROPOMI and CALIOP depends significantly on the
thickness of the plume. Thicker plumes seem to be better captured by TROPOMI and the meandifference reduces with the thickness of the plumes, the mean difference between the TROPOMI andCALIOP mid aerosol layer is just 50 m for very thick plumes (>3 km). The main reason is the insensitivity
to the surface bias for thick plume in S5P ALH.
There is a notable difference between the NRTI and OFFL/RPRO cloud-free scene selections as ofversion 2.0.0 (see section 4.1).

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These above-mentioned studies and up to date validation results are available in the Routine Operations
Consolidated Validation Reports (ROCVR) that are accessible through the MPC Validation Data
Analysis Facility (VDAF) website at http://mpc-vdaf.tropomi.eu. The ROCVR reports are issued
quarterly, and reports released after September 2021 include validation results based on processor
version 2.x.x.
The target uncertainty requirements for ALH are defined in the S5p Calibration and Validation Plan
[RD01] and summarized in Table 1. The ALH is compliant with the requirements over oceans and dark
land surfaces.

Parameter
ALH

Data productAerosol Layer Height

VerticalResolution
Total column

Bias<100hPa (1 Km)

Random<50hPaTable 1: ALH data product requirements extracted from the S5p Calibration and Validation Plan [RD01]

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Processing baseline description

Table 2 contains the history of the ALH processor versions. Note that the processor version for ALH is changing when there is a change to any of the products
belonging to the NL-L2 processor suite (NO2, CO, CH4, AI, ALH, O3 PR) even if the change is not affecting the ALH product.
Processor
Version02.05.00

In operation starting from

In operation until

Relevant Improvements

NRTI: orbit 28078, 2023-03-15
OFFL: orbit 28031, 2023-03-12

Current version

Minor format changes (see section 6.1)
- Introduction of S5P/TROPOMI-based LER surface
database (see section 5)- Minor format changes (see section 6.1)

02.04.00

NRTI: orbit 24697, 2022-07-20
OFFL: orbit 24655, 2022-07-17
RPRO: orbit 2818, 2018-04-30

Orbit 28074, 2023-03-15
Orbit 28030, 2023-03-12
Orbit 24779, 2022-07-25

Note 1: It is recommended to use the RPRO products in theorbit range 24655 - 24779, period for which also OFFL
products are available. This, because the OFFL products inthat orbit range will be removed.
Note 2: Starting from this processor version, new improved
Level 1b version 2.1 data products are used as input [RD04]

02.03.01

02.02.00

NRTI: orbit 21223, 2021-11-17
OFFL: orbit 21188, 2021-11-14

NRTI: orbit 19308, 2021-07-05
OFFL: orbit 19258, 2021-07-01

Orbit 24697, 2022-07-20
Orbit 24654, 2022-07-17

Orbit 21222, 2021-11-17
Orbit 21187, 2021-11-14

Minor format changes: text changed in attribute description
for two fields (see section 6.1)
- The pixel selection scheme has been updated. The
Enterprise Cloud Mask (ECM) cloud mask is now theprimary cloud filter for OFFL, FRESCO cloud mask for
NRTI, with the aerosol index used to add pixels that haveboth a too high cloud fraction and a high UV Aerosol
Index (UVAI) value. These are likely thick aerosol events
where the cloud mask considers this a cloud. Full details
on the new pixel selection scheme are provided [RD02]- Changes in format (see section 6.1)

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Note: Starting from this processor version, new improved
Level 1b version 2.0 data products are used as input [RD04].

01.04.00

NRTI: orbit 16259, 2020-12-02
OFFL: orbit 16213, 2020-11-29

Orbit 19306, 2021-07-05
Orbit 19257, 2021-07-01

No changes with respect to previous version

01.03.02

NRT: orbit 10171, 2019-09-30
OFFL: orbit 8815, 2019-06-26

Orbit 16256, 2020-12-02
Orbit 16212, 2020-11-29

No changes with respect to previous version

01.03.01

RPRO: orbit 2818, 2018-04-30
OFFL: orbit 7907, 2019-04-23

Orbit 7424, 2019-03-20
Orbit 8814, 2019-06-26

No changes with respect to previous version

01.03.00

OFFL: orbit 7425, 2019-03-20

Orbit 7906, 2019-04-23

Initial version

Table 2: History of ALH processor versions

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Product Quality

3.1

Recommendations for data usage

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The ALH is very sensitive to cloud contamination. However, aerosols and clouds can be difficult todistinguish, and ALH is computed for all FRESCO effective cloud fractions smaller than 0.04 (NRTI) and
VIIRS cloud fractions smaller than 0.02 (OFFL). Cloud flags are available from FRESCO and VIIRS,
and are strongly recommended to filter for residual clouds. A sunglint mask is also available to screen
sunglint regions, which are not filtered beforehand. These and other sources of uncertainties areindicated with the qa_value. Use of pixels with a qa_value below 0.5 is not recommended.
The variables aerosol_mid_pressure_precision and aerosol_mid_height_precision canalso be further used to diagnose the quality of the ALH.
For further details, data users are encouraged to read the Product User Manual (PUM) [RD03] andAlgorithm Theoretical Basis Document (ATBD) [RD02] associated with this data product, available on
https://sentinels.copernicus.eu/web/sentinel/technical-guides/sentinel-5p/products-algorithms.

3.2

Validation results

The data are validated for reprocessed data using the data processor up to version 01.04.00, see section
1. These data were selected using high UV AI. Version 02.xx.xx will include more data: all pixels with
sufficiently low cloud fraction. The UV AI is only used to avoid cloud filtering for thick plumes of smoke
and volcanic ash, which are important to include in the retrieval. The validation results are valid for all
versions, since the retrieval was not changed markedly in version 2. However, the selection of pixels isnow based on different cloud filters in NRTI and OFFL. Details on the consequences of this and up todate validation results are available in the Routine Operations Consolidated Validation Reports(ROCVR) that are accessible through the MPC Validation Data Analysis Facility (VDAF) website at
http://mpc-vdaf.tropomi.eu. The ROCVR reports are issued quarterly, and reports released after
September 2021 include validation results based on processor version 2.x.x.

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Data Quality Remarks

Currently, the following data quality issues are known and should be kept in mind when looking at the
Aerosol Layer Height product and also at validation results.

4.1

Known Data Quality Issues

Bias to clouds
As mentioned, the ALH is very sensitive to clouds, and the height will be strongly biased towards thecloud height for partially clouded pixels.
High surface albedo
It is known that high surface albedos negatively influence the ALH, biasing the ALH towards the surface.
In general, the ALH over (dark) oceans is considered reliable to within the requirement of 1000 m or 100
hPa. Over land, especially bright surfaces, the accuracy may be lower, and the use of the ALH productover bright surfaces like deserts is not advisable.
Difference in NRTI and OFFL cloud-free scene selections (since version 2.0.0)
There is a notable difference between the NRTI and OFFL cloud-free scene selections as of version
2.0.0. During OFFL processing the VIIRS Enterprise Cloud Mask (ECM) cloud mask is used to selectcloud-free scenes for ALH processing. However, during NRTI processing the VIIRS ECM information is
not yet available, and the S5P/FRESCO cloud mask is used to select cloud-free scenes. Since the
FRESCO cloud mask represents a (radiative) effective cloud fraction and the VIIRS ECM a geometriccloud fraction, differences between the cloud masks can be significant, which results in a notabledifferent selection of cloud-free pixels. This is not an error, but for ALH purposes the VIIRS ECM cloud
filter is considered to be superior to the FRESCO cloud mask. For pixels which were marked cloud-freeby either cloud filter, the difference in retrieved ALH from NRTI and OFFL processing was very small.

4.2

Solved Data Quality Issues

Data in snow_ice_flag variable for pixels with SZA > 88° (solved in version 02.04.00)
The snow_ice_flag value for ground pixels with SZA > 88° is incorrectly set to 255, the NISE flagfor “ocean”, rather than the FillValue 254 (the NISE flag for an error). Since ground pixels with SZA >88° are not processed, these pixels do not have ALH column data, hence the ALH data quality is notaffected. This has been corrected in version 02.04.00.
Geolocation co-added when they should not be (solved in version 02.03.01)
In version 02.02.00, the geolocation of pixels near the pole show a shift of up to 300 meters due to a
co- addition activity performed by mistake. This has been corrected in version 02.03.01.
Metadata/Attributes (solved in version 02.02.00)
The spatial resolution of the TROPOMI measurements is improved by bringing the along track groundpixel size from 7.0 to 5.5 Km starting on 6th August 2019. Note that, after this operations change, themetadata/Attributes fields related to the spatial resolution, remained unchanged (hence not aligned tothe improved resolution). These fields have been updated with the activation of Level 2 processors
version 02.02.xx.

4.3

Data Features

This section describes some characteristics of the data that might seem anomalous, however they arephysically correct and not related to any problem.

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Pixel geolocation around North Pole (feature)
The solar irradiance is measured on a daily basis over the North Pole at a reference azimuth angle toremove seasonal effects on the measurements. To this end, a yaw manoeuvre is executed when the
instrument is still in radiance mode, causing possible distortion on the scanlines observed during thismanoeuvre (i.e. crossing scanlines, "bow-tie" ground pixel shape instead of rectangular). This occurs at
most during the last 26 seconds of radiance measurements in few orbits (7-9 per week).
Though this may seem anomalous, it is physically correct, and not related to any problem on the data
geolocation.
New cloud mask for S-NPP used during OFFL ALH processing
NOAA no longer supports the VIIRS cloud mask (VCM or VICMO) product, which is discontinued(second quarter 2020) in favour of the Enterprise Cloud Mask (ECM). An update to the S5P-NPP L2processor (to version 01.01.00) has happened (orbit 12432, date 07-03-2020) to ingest the new cloudmask. It should, however, be noted that there are significant differences between the cloud mask fields
themselves: E.g., compared to VCM, ECM tends to indicate fewer confidently clear scenes over land,
but more over sea. Therefore, values in the cloud/clear counts used to calculate the cloud fraction for
the filtering of the OFFL AER_LH product are now different. Please note that the NRTI AER_LH does
not use this cloud mask and is not affected.
The change in cloud fractions (sign and magnitude) are dependent on the day and location. However,the current thresholds for cloud filtering (which are the same for CH4) do not affect the AER_LH product,i.e., cloudy scenes are filtered properly. The new cloud mask values available to users are expected toperform better than before and the user is encouraged to use the available cloud masks to filter forresidual clouds. Full assessment of data quality will come after the new processor has been runninglong enough.

4.4

Mission Operations Changes

A change in the Copernicus Sentinel 5P operations scenario increasing the spatial resolution from 7.0
km to 5.5 km along track for all measurements, became operational starting from 6 August 2019, orbit
9388.

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Algorithm Change Record

For a detailed description of the L2__AER_LH algorithm, please refer to the ATBD [RD02].
Version 02.04.00
The following improvements have been implemented with respect to the previous version of the data:•

The Level 1B radiometric calibration of the radiance data has improved. For ALH the
implications are small.

•

New surface reflectance information is used, from the Lambertian Equivalent Reflectivity (LER)
database, based on TROPOMI data. Previously a LER database was used based on GOME-2
data. The implications on ALH are considerable, especially the higher resolution of the new
database (0.125Ox0.125O instead of 0.25Ox0.25O) and TROPOMI-based data benefits the ALH
retrieval. However, the biases over land remain large and are not resolved with the use of the
new surface database.

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Data Format

The product is stored as NetCDF4 file. The NetCDF4 file contains both the data and the metadata forthe product.
For OFFL data the product is stored as a single file per satellite orbit, for NRTI data the product is stored
as multiple files per orbit.
Please note that consecutive data granules of the NRTI product show an overlap of about 12 scan lines.
Details of the data format are provided in the Product User Manual (PUM) [RD03].

6.1

Data format changes

6.1.1

Version 02.05.00

Attribute fields with text changes
In variable /PRODUCT dimension ‘state_vector_length’ → text changed (from ‘2’ to ‘-1’)
In variable /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/wavelength_calibration_offset
attribute ‘long_name’ → text changed (from ‘wavelength offset’ to ‘radiance wavelength offset’)In variable /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/wavelength_calibration_offset_precisionattribute ‘long_name’ → text changed (from ‘wavelength offset precision’ to ‘radiance wavelength offset precision’)In variable /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/wavelength_calibration_stretch
attribute ‘long_name’ → text changed (from ‘wavelength stretch’ to ‘radiance wavelength stretch’)In variable /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/wavelength_calibration_stretch_precisionattribute ‘long_name’ → text changed (from ‘wavelength stretch precision’ to ‘radiance wavelength stretch precision’)In variable /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/wavelength_calibration_chi_square
attribute ‘long_name’ → text changed (from ‘wavelength calibration chi square’ to ‘radiance wavelength
calibration chi square’)In variable /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/wavelength_calibration_irradiance_chi_square
attribute ‘long_name’ → text changed (from ‘wavelength calibration irradiance chi squared’ to‘irradiance wavelength calibration chi squared’)
6.1.2

Version 02.04.00

New fields added/METADATA/QA_STATISTICS/number_of_thermal_instability_warning_occurrences
In variable:/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/processing_quality_flags
Added element to attribute ‘flag_meanings’: [success, radiance_missing,irradiance_missing, input_spectrum_missing, …, thermal_instability_warning]
Added element to attribute ‘flag_masks’: [255, 255, 255, …, 1073741824]
Added element to attribute ‘flag_values’: [0, 1, 2, 3, 4, …, 1073741824]
6.1.3

Version 02.03.01

Renamed fields/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/wavelength_calibration_irradiance_offset
attribute ‘long_name’ → text changed (from ‘wavelength offset’ to ‘irradiance wavelength offset’)/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/wavelength_calibration_irradiance_offset
attribute ‘ancillary_variables’ → text changed (from ‘wavelength_calibration_offset_precision’ to‘wavelength_calibration_irradiance_offset_precision’)S5P MPC Product Readme Aerosol Layer Height V02.05.00
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Version 02.02.00

New fields added/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_mid_pressure_not_clipped/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_optical_thickness attributecomment /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_optical_thickness
attribute radiation_wavelength/METADATA/QA_STATISTICS attribute number_of_missing_scanlines/METADATA/QA_STATISTICS attribute number_of_max_num_outlier_exceeded_error_occurrences/METADATA/GRANULE_DESCRIPTION attribute CollectionIdentifier
Removed fields/METADATA/ISO_METADATA/gmd:identificationInfo/gmd:spatialResolution
Renamed fields/PRODUCT/qa_value attribute valid_min_→ /PRODUCT/qa_value attribute valid_min/PRODUCT/qa_value attribute valid_max_→ /PRODUCT/qa_value attribute valid_max/METADATA/QA_STATISTICS attribute number_of_aai_warning_occurrences→ /METADATA/QA_STATISTICS attribute number_of_AAI_warning_occurrences/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_optical_thickness attributeproposed_standard_name→ standard_nameS5P MPC Product Readme Aerosol Layer Height V02.05.00
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Product Availability

All S5P/TROPOMI data are available on the Copernicus Open Data Hub https://scihub.copernicus.eu.
Also, the full mission reprocessed products can be found on the mentioned Open Access Hub and canbe identified by the file class ‘RPRO’ in the filenames. The collection identifier is ‘03’, the same used forthe operational dataset that is available since mid-July 2022 (all with version 2.4.0).
The list of major mission data gaps due to acquisition faults or satellite/instrument disruption is available
at https://sentinel.esa.int/web/sentinel/missions/sentinel-5p/mission-status. For those periods the data
are permanently lost.
RPRO dataset gaps: additional gaps are present on the reprocessed dataset (see Table 3) due to theunavailability of Level 0 (L0) input data during the full mission reprocessing campaign.

Orbit

Gap start time

Gap stop time3546

20/06/2018 08:31:35

20/06/2018 08:51:37

9755
10782
19782
19785
20254

31/08/2019 23:46:24

01/09/2019 00:06:25

12/11/2019 08:39:57

12/11/2019 09:29:55

07/08/2021 18:09:52

07/08/2021 18:27:54

07/08/2021 22:34:02

07/08/2021 22:50:52

10/09/2021 00:01:42

10/09/2021 00:21:43

Table 3: Gaps on RPRO dataset due to the unavailability of L0 input data
during the full mission reprocessing campaign
Information on data handling tools is available from the web page http://www.tropomi.eu/tools.
For further questions regarding S5P/TROPOMI data products please contact
EOSupport@Copernicus.esa.int.
The access and use of any Copernicus Sentinel data available through the Copernicus Sentinel Data
Hub is governed by the Legal Notice on the use of Copernicus Sentinel Data and Service Informationand is given here:
https://sentinels.copernicus.eu/documents/247904/690755/Sentinel_Data_Legal_Notice.

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References[RD01]

Sentinel-5 Precursor Calibration and Validation Plan for the Operational Phase
source: ESA; ref: ESA-EOPG-CSCOP-PL-0073;
url: https://sentinel.esa.int/documents/247904/2474724/Sentinel-5P-Calibration-andValidation-Plan.pdf[RD02]

Sentinel-5 precursor/TROPOMI Level 2 Algorithm Theoretical Basis Document of the
Aerosol Layer Heightsource: KNMI; ref: S5P-KNMI-L2-0006-RP;
url: https://sentinels.copernicus.eu/documents/247904/2476257/Sentinel-5PTROPOMI-ATBD-Aerosol-Height[RD03]

Sentinel-5 precursor/TROPOMI Level 2 Product User Manual Aerosol Layer Heightsource: KNMI; ref: S5P-KNMI-L2-0026-MA;
url: https://sentinel.esa.int/documents/247904/2474726/Sentinel-5P-Level-2-ProductUser-Manual-Aerosol-Layer-Height[RD04]

Algorithm theoretical basis document for the TROPOMI L01b data processor
source: KNMI; ref: S5P-KNMI-L01B-0009-SD;
url: https://sentinels.copernicus.eu/documents/247904/2476257/Sentinel-5PTROPOMI-Level-1B-ATBD[D01]

VIIRS Calibration Support Team (VCST). (2017). VIIRS/NPP Day/Night Band 6-Min
L1B Swath SDR- 750m NRT [Data set]. NASA LANCE MODIS at the MODAPS.
https://doi.org/10.5067/viirs/vnp02dnb_nrt.001[D02]

Winker, D. (2016). CALIPSO LID L1 ValStage1 HDF File - Version 3.40 [Data set].
NASA Langley Atmospheric Science Data Center DAAC.
https://doi.org/10.5067/caliop/calipso/cal_lid_l1-valstage1-v3-40

More information on this data product is available from the Sentinel product webpage:https://sentinels.copernicus.eu/web/sentinel/technical-guides/sentinel-5p/products-algorithms,
and from the corresponding TROPOMI product webpage http://www.tropomi.eu/data-products.

S5P MPC Product Readme Aerosol Layer Height V02.05.00
issue 2.4, 2023-03-15 - Released

S5P-MPC-KNMI-PRF-AER_LH
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Abbreviations and acronyms(A)AI(Absorbing) Aerosol Index

ALH

Aerosol Layer Height

ATBD

Algorithm Theoretical Basis Document

BIRA-IASBRoyal Belgian Institute for Space Aeronomy

DLR

German Aerospace Center / Deutsches Zentrum für Luft- und Raumfahrt

DOI

Digital Object Identifier

ECM

Enterprise Cloud Mask

ESA

European Space Agency

ESL

Expert Support Laboratory

KNMI

Royal Netherlands Meteorological Institute / Koninlijk Nederlands
Meteorologisch Instituut

LER

Lambertian-Equivalent Reflectivity

MPC

Mission Performance Centre

NASA

National Aeronautics and Space Administration

NRTI

Near Real TIme (timeliness of products)

OFFL

Offline (timeliness of products)

OMI

Ozone Monitoring Instrument

OMPS

Ozone Mapper and Profiling Suite

PRF

Product Readme File

PUM

Product User Manual

QWG

Quality Working GroupROCVR

Routine Operations Consolidated Validation Report

S5P

Sentinel-5 Precursor

S5PVT

Sentinel-5 Precursor Validation Team

TCCON

Total Carbon Column Observing Network

TROPOMI

Tropospheric Monitoring Instrument

UVAI

UV Aerosol Index

VCM

VIIRS Cloud Mask

VDAF

Validation Data Analysis Facility