Page Summary
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The dataset provides Level 3 formaldehyde trace gas information on a regular grid from TEMPO observations.
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Level 3 data is derived by combining information from Level 2 files.
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This is a quality-controlled dataset, filtering out data with high cloud cover, extreme solar zenith angles, and poor quality flags.
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The dataset includes bands for formaldehyde vertical columns, uncertainty, data quality, and various ancillary data.
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The dataset is in the public domain with no restrictions on use and distribution.
- Dataset Availability
- 2023-08-01T00:00:00Z–2025-09-16T21:03:09Z
- Dataset Producer
- QA Filtered: Google and NASA ASDC
- Tags
Description
Formaldehyde Level 3 collection provides trace gas information on a regular grid covering the TEMPO field of regard for nominal TEMPO observations. Level 3 files are derived by combining information from all Level 2 files constituting a TEMPO East-West scan cycle. The rasters contain information on formaldehyde vertical columns, ancillary data used in air mass factor calculations and reference sector or de-striping corrections, and retrieval quality flags. The re-gridding algorithm uses an area-weighted approach.
The QA Filtered TEMPO HCHO L3 dataset is a quality-controlled version of the original data. It is generated by removing data points with high cloud cover (>50%), extreme solar zenith angle (>80 degrees), and main data quality (flag > 0).
- A version of this dataset without QA filters applied is available as NASA/TEMPO/HCHO_L3
- General Documentation
Bands
Bands
Pixel size: 2226 meters (all bands)
| Name | Units | Pixel Size | Description |
|---|---|---|---|
weight
|
km^2 | 2226 meters | Sum of Level 2 pixel overlap areas. Represents the weighting factor for each grid cell, indicating the fraction of the grid cell area with valid data. |
vertical_column
|
molecules/cm^2 | 2226 meters | HCHO vertical column |
vertical_column_uncertainty
|
molecules/cm^2 | 2226 meters | HCHO vertical column uncertainty |
main_data_quality_flag
|
Dimensionless | 2226 meters | Main data quality flag which is always 0, indicating good quality data. |
num_vertical_column_samples
|
Dimensionless | 2226 meters | Number of vertical column samples |
min_vertical_column_sample
|
molecules/cm^2 | 2226 meters | Smallest vertical column sample |
max_vertical_column_sample
|
molecules/cm^2 | 2226 meters | Largest vertical column sample |
solar_zenith_angle
|
deg | 2226 meters | Data is filtered to include only observations with solar zenith angle less than or equal to 80 degrees. |
viewing_zenith_angle
|
deg | 2226 meters | Viewing zenith angle at pixel center |
relative_azimuth_angle
|
deg | 2226 meters | Relative azimuth angle at pixel center |
surface_pressure
|
hPa | 2226 meters | Surface pressure |
terrain_height
|
m | 2226 meters | Terrain height |
snow_ice_fraction
|
Dimensionless | 2226 meters | Fraction of pixel area covered by snow and/or ice |
fitted_slant_column
|
molecules/cm^2 | 2226 meters | HCHO fitted slant column |
fitted_slant_column_uncertainty
|
molecules/cm^2 | 2226 meters | HCHO fitted slant column uncertainty |
albedo
|
Dimensionless | 2226 meters | Surface albedo |
amf
|
Dimensionless | 2226 meters | HCHO air mass factor |
eff_cloud_fraction
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Dimensionless | 2226 meters | Data is filtered to include only observations with effective cloud fraction less than or equal to 50%. |
amf_cloud_fraction
|
Dimensionless | 2226 meters | Cloud radiance fraction for AMF calculation |
amf_cloud_pressure
|
hPa | 2226 meters | Cloud pressure for AMF calculation |
Terms of Use
Terms of Use
This dataset is in the public domain and is available without restriction on use and distribution. See NASA's Earth Science Data & Information Policy for additional information.
Citations
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NASA/LARC/SD/ASDC. (n.d.). TEMPO gridded HCHO vertical columns V03 (PROVISIONAL) [Data set]. NASA Langley Atmospheric Science Data Center DAAC. Retrieved from https://doi.org/10.5067/IS-40e/TEMPO/HCHO_L3.003
DOIs
Explore with Earth Engine
Code Editor (JavaScript)
var collection = ee . ImageCollection ( 'NASA/TEMPO/HCHO_L3_QA' ) . filterDate ( '2024-04-01' , '2024-04-05' ) var visParams = { min : 0 , max : 1.5e16 , bands : [ 'vertical_column' ], palette : [ '000080' , '0000D9' , '4000FF' , '8000FF' , '0080FF' , '00D9FF' , '80FFFF' , 'FF8080' , 'D90000' , '800000' ] }; Map . setCenter ( - 95.06 , 42.02 , 3 ) Map . addLayer ( collection , visParams , 'HCHO vertical column' )
