Haze, dust and smoke in the air, near real-time (Aqua MODIS, 3 km, alt)
What it measures. How much haze, dust, and smoke is in the air over ocean and land at 3 km detail, an improved version with better handling of urban areas and pollution-particle uncertainty.
How it's made. Retrieved from the MODIS sensor on the Aqua satellite using the updated Collection 6.1 Dark Target method, processed in near real-time at the finer 3 km resolution for air-quality use.
How & where you'd use it. Supports near real-time air-quality monitoring, tracking dust and wildfire smoke, and studying how airborne particles influence health and climate.
What's measured
Coverage & cadence
- Time span2017-10-20 → ongoing
- Measured byAQUA (MODIS)
- Processing levelLevel 2
- Spatial extent-180, -90, 180, 90
- FormatsHDF-EOS
- 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
The new Collection 6.1 (C61) MYD04_3K product is an improved version based on algorithm changes in Dark Target (DT) Aerosol retrieval over urban areas and uncertainty estimates for Deep Blue (DB) Aerosol retrievals. The MODIS level-2 atmospheric aerosol product provides retrieved ambient aerosol optical properties, quality assurance, and other parameters, globally over ocean and land. In Collection 5, and earlier collections, there was only one aerosol product (MOD04_L2) at 10km (at nadir) spatial resolution. Starting from C6, the Dark Target (DT) Aerosol algorithm team provided a new 3 km spatial resolution product (MOD04_3k) intended for the air quality community. The MOD04_3K product is based on the same algorithm and Look up Tables as the standard Dark Target aerosol product. Because of finer resolution, subtle differences are made in selecting pixels for retrieval and in determining QA. The only differences between the existing 10km algorithm and the 3km algorithm are: 1) the size of the pixel-arrays defining each retrieval box (6x6 retrieval boxes of 36 pixels at 0.5km resolution for 3km algorithm as oppose to 20x20 retrieval boxes of 400 pixels at 0.5km resolution for 10km product); 2) the minimum percentage of good pixels required for a retrieval (a minimum of 5 pixels over ocean and 6 pixels over land instead of a minimum of 10 pixels over ocean or 12 pixels over land for 10km product retrieval); 3) the 10km algorithm attempts a poor quality retrieval while 3km algorithm does not. Everything else is same in two products. For more information on C6.1 changes and updates, visit the MODIS Atmosphere website at: https://modis-atmosphere.gsfc.nasa.gov/documentation/collection-61
Get the data
import earthaccess
earthaccess.login(strategy="netrc") # free Earthdata Login
results = earthaccess.search_data(
short_name="MYD04_3K",
version="6.1NRT",
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 LANCEMODISBrowsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.