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Full catalog/MIL3DCFA
MIL3DCFA·v001·dataset

Cloud cover broken down by altitude, daily (MISR)

MISR Level 3 Cloud Fraction by Altitude Product covering a day V001
atmosphere NASA LARC_CLOUD Level 3 active HDF-EOS2
In plain English

What it measures. Daily maps of how often clouds occur, broken down by the height of their tops, so you can see how much cloud sits at each altitude layer. Cloud fraction is just the share of pixels that were cloudy.

How it's made. Produced from the MISR instrument's nine-angle cameras on NASA's Terra satellite, which use the slightly different views to figure out cloud-top height, summarized into a half-degree global grid.

How & where you'd use it. Useful for studying how clouds are distributed by altitude and how that pattern changes, which feeds into climate and atmospheric research.

What's measured

ATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD HEIGHT

Coverage & cadence

  • Time span1999-12-18 → ongoing
  • Measured byTerra (MISR)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • 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

This file contains the public MISR Level 3 Cloud Fraction by Altitude Product covering a day. MIL3DCFA_001 is the Multi-angle Imaging SpectroRadiometer (MISR) Level 3 Cloud Fraction by Altitude Product covering a day version 1. It provides the frequency of cloud occurrence partitioned into different cloud top height bins at a global and monthly scale with a latitude/longitude resolution of 0.5 degrees by 0.5 degrees and a vertical resolution of 500m. For each height bin, the frequency of cloud occurrence of a region over a time period is represented by the temporal mean of the spatial coverage of cloud tops. The spatial coverage of clouds is called cloud fraction, which is defined as the ratio of the number of cloudy pixels to the total number of cloudy and cloud-free pixels observed by the instrument. Clouds are assigned to height bins based on their top height, as the MISR stereoscopic technique retrieved. Data collection for this product is complete. The MISR instrument consists of nine push-broom cameras that measure radiance in four spectral bands. Global coverage is achieved in nine days. The cameras are arranged with one camera pointing toward the nadir, four forward, and four aftward. It takes seven minutes for all nine cameras to view the same surface location. The view angles relative to the surface reference ellipsoid are 0, 26.1, 45.6, 60.0, and 70.5 degrees. The spectral band shapes are nominally Gaussian, centered at 443, 555, 670, and 865 nm. MISR is designed to view Earth with cameras pointed in 9 different directions. As the instrument flies overhead, each piece of Earth's surface below is successfully imaged by all nine cameras in 4 wavelengths (blue, green, red, and near-infrared). The goal of MISR is to improve our understanding of the effects of sunlight on Earth and distinguish different types of clouds, particles, and surfaces. Specifically, MISR monitors the monthly, seasonal, and long-term trends in three areas: 1) amount and type of atmospheric particles (aerosols), including those formed by natural sources and by human activities; 2) amounts, types, and heights of clouds, and 3) distribution of land surface cover, including vegetation canopy structure.

Get the data

mil3dcfa_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MIL3DCFA",
    version="001",
    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 LARC_CLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.