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Full catalog/S5P_L2__HCHO___HiR
S5P_L2__HCHO___HiR·v2·dataset

Formaldehyde in the air (Sentinel-5P)

Sentinel-5P TROPOMI Tropospheric Formaldehyde HCHO 1-Orbit L2 5.5km x 3.5km V2 (S5P_L2__HCHO___HiR) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. How much formaldehyde is in the air over a given spot, measured as the total amount in the column of atmosphere above. Formaldehyde is a marker of certain pollution and natural plant emissions.

How it's made. Comes from the TROPOMI instrument on Europe's Sentinel-5P satellite, which splits incoming light into a spectrum to detect the gas; this is per-orbit data at about 5.5 km detail.

How & where you'd use it. Used to map sources of air pollution and to study chemistry that leads to ozone formation and poor air quality near the ground.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRYATMOSPHERE › ATMOSPHERIC CHEMISTRY › CARBON AND HYDROCARBON COMPOUNDS › FORMALDEHYDE

Coverage & cadence

  • Time span2018-04-30 → ongoing
  • Measured bySentinel-5P (TROPOMI)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • StatusACTIVE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

Starting from August 6th in 2019, Sentinel-5P TROPOMI along-track high spatial resolution (~5.5km at nadir) has been implemented. Starting from July 13th in 2020, five Sentinel-5P TROPOMI level-2 products including total and tropospheric column ozone, sulfur dioxide, CLOUD, and formaldehyde have been generated in processor version 2. For data before August 6th of 2019, please check S5P_L2__HCHO___1 data collection. For data between August 6th of 2019 and July 13th of 2020, please check S5P_L2__HCHO___HiR_1 data collection. For data after July 13th of 2020, please check S5P_L2__HCHO___HiR_2 data collection. The Copernicus Sentinel-5 Precursor (Sentinel-5P or S5P) satellite mission is one of the European Space Agency's (ESA) new mission family - Sentinels, and it is a joint initiative between the Kingdom of the Netherlands and the ESA. The sole payload on Sentinel-5P is the TROPOspheric Monitoring Instrument (TROPOMI), which is a nadir-viewing 108 degree Field-of-View push-broom grating hyperspectral spectrometer, covering the wavelength of ultraviolet-visible (UV-VIS, 270nm to 495nm), near infrared (NIR, 675nm to 775nm), and shortwave infrared (SWIR, 2305nm-2385nm). Sentinel-5P is the first of the Atmospheric Composition Sentinels and is expected to provide measurements of ozone, NO2, SO2, CH4, CO, formaldehyde, aerosols and cloud at high spatial, temporal and spectral resolutions. The retrieval algorithm for Sentinel-5P TROPOMI HCHO from ultraviolet spectral measurements is the Differential Optical Absorption Spectroscopy (DOAS) method. The relevant information of absorption cross section, instrument characteristics, cloud cover as well as aerosol index are utilized to derive HCHO slant column density (SCD). The air mass factor (AMF) Look-up table has been created with the VLIDORT 2.6 radiative transfer model at the wavelength of 340 nm, and the AMF is used to compute the total column averaging kernels (AK). The background normalization of the slant columns is essential for weak absorbent like formaldehyde to compensate for possible systematic offsets. The main outputs of the DOAS algorithm are the vertical column density (VCD), SCD, AMF, uncertainty, AK, and quality flags.

Get the data

s5p_l2__hcho___hir_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="S5P_L2__HCHO___HiR",
    version="2",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.