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Full catalog/VJ118C1
VJ118C1·v002·dataset

How much sunlight reaches the ground, daily (VIIRS, NOAA-20)

VIIRS/JPSS1 Downward Shortwave Radiation Daily L3 Global 0.05Deg CMG V002
land NASA LPCLOUD Level 3 active HDF-EOS5
In plain English

What it measures. How much sunlight reaches the land surface each day, measured across the short-wavelength part of the spectrum that drives heating and plant growth.

How it's made. Estimated from the VIIRS instrument on the NOAA-20 satellite using look-up tables that account for clouds, haze, and viewing angle, then gathered into a daily global map at about 5 km resolution.

How & where you'd use it. Valuable for solar energy planning and for land and climate models, since incoming sunlight is a key driver of temperature, evaporation, and how plants grow.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCELAND SURFACE › SURFACE RADIATIVE PROPERTIES › ALBEDOLAND SURFACE › SURFACE RADIATIVE PROPERTIES › ANISOTROPYATMOSPHERE › ATMOSPHERIC RADIATION › SHORTWAVE RADIATION

Coverage & cadence

  • Time span2018-01-05 → ongoing
  • Measured byNOAA-20 (VIIRS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS5
  • StatusACTIVE

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 NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS) Downward Shortwave Radiation (DSR) Level 3 Climate Modeling Grid (CMG) product produced at 0.05 degree pixel resolution at daily intervals. DSR is the incident solar radiation over land surfaces in the shortwave spectrum (300-4,000 nanometers) and is a significant variable in land surface models (LSMs), receiving increased attention due to its importance for the management and operation of solar energy systems. The VJ118 algorithm adapts the narrowband look-up table (LUT) approach to estimate DSR. The LUTs consider different types of loadings of aerosols and clouds at a variety of illumination/viewing geometry. The Algorithm Theoretical Basis Document (ATBD) is forthcoming and will provide additional details regarding the methodology used to create the data. The VJ118C1 product is aggregated from VJ118A1 files and includes one set of global 3-hour DSR variables and one set of daily mean DSR.

Get the data

vj118c1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ118C1",
    version="002",
    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 LPCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.