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Full catalog/modis-aqua-myd21a2
modis-aqua-myd21a2·dataset

Land surface temperature every 8 days, 1 km (Aqua)

MODIS Aqua Land Surface Temperature 3-Band Emissivity 8-Day L3 Global 1km
land ESA ESA Copernicus active
In plain English

What it measures. It reports how hot the actual ground surface is (not the air above it) averaged over 8 days at 1-kilometer detail, for both day and night. It also includes emissivity, a measure of how efficiently different surfaces give off heat.

How it's made. Generated by ESA Copernicus from the thermal-infrared bands of NASA's MODIS sensor on Aqua, using a physics-based temperature-and-emissivity method with atmospheric correction, delivered as a Level-3 grid.

How & where you'd use it. Used to study urban heat, drought, and heat stress on crops and ecosystems, and to compare daytime versus nighttime surface temperatures across regions.

What's measured

MODISAquaNASASatelliteGlobalLand Surface TemperatureLSTEmissivityThermal1kmMYD21A2

Coverage & cadence

  • Time span2002-07-04 → ongoing
  • Spatial extent-180, -90, 180, 90

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The MODIS Aqua MYD21A2 Version 6.1 product provides an 8-day composite of Land Surface Temperature (LST) and emissivity at 1 km spatial resolution. The dataset is based on the ASTER Temperature/Emissivity Separation (TES) algorithm, which retrieves LST and spectral emissivity simultaneously from MODIS thermal infrared bands 29, 31, and 32 using a physics-based approach combined with a Water Vapor Scaling (WVS) atmospheric correction method. The product is generated by averaging all cloud-free observations from the MYD21A1D (daytime) and MYD21A1N (nighttime) daily acquisitions within the 8-day compositing period. Both daytime and nighttime observations are included in a single file as separate science data layers, including LST, quality control (QC), view zenith angle, and observation time, while emissivity values for bands 29, 31, and 32 represent the average of both daytime and nighttime measurements.

Get the data

copernicus_access.py
# ESA Copernicus Data Space — open STAC API (free account)
from pystac_client import Client

cat = Client.open("https://stac.dataspace.copernicus.eu/v1")
search = cat.search(
    collections=["modis-aqua-myd21a2"],   # add _cog or _nc for a format variant
    bbox=(-10, 35, 30, 60),             # your area (W,S,E,N)
    datetime="2024-01-01/2024-12-31",
)
items = list(search.items())            # then read assets with rioxarray / xarray
Browsing the Copernicus STAC is open; downloading bytes needs a free Copernicus Data Space account.