How much water plants release, gap-filled 8-day (VIIRS, Suomi-NPP, 500 m)

In plain English

What it measures. How much water leaves the land surface through evaporation and plant transpiration over each 8-day period, plus the related energy used, mapped globally at 500 meters. It also reports the potential amount under ideal conditions.

How it's made. Calculated with the Penman-Monteith approach using VIIRS satellite data from Suomi-NPP plus weather reanalysis, then gap-filled at year's end to patch over poor-quality input.

How & where you'd use it. Supports water management, drought and irrigation planning, and understanding how landscapes lose water; because it's gap-filled annually, it isn't available in near-real time.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR PROCESSES › EVAPOTRANSPIRATIONATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR PROCESSES › EVAPORATIONATMOSPHERE › PRECIPITATION › PRECIPITATION PROFILES › LATENT HEAT FLUX

Coverage & cadence

Time span2012-01-01 → ongoing
Measured bySuomi-NPP (VIIRS)
Processing levelLevel 4
Spatial extent-180, -90, 180, 90
FormatsHDF-EOS5
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 NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Actual and Potential Evapotranspiration product is a gap-filled 8-day composite dataset produced at 500 meter (m) pixel resolution. The VIIRS ET and PET algorithm is based on the Penman-Monteith equation, which includes inputs of daily meteorological reanalysis data along with VIIRS remotely sensed data products such as 8-day vegetation property dynamics and daily surface albedo. The VNP16A2GF will be generated at the end of each year when the entire yearly 8-day VNP15A2H is available. Hence, the gap-filled VNP16A2GF is the improved VNP16A2, which has cleaned the poor-quality inputs from 8-day Leaf Area Index and Fraction of Photosynthetically Active Radiation (LAI/FPAR) based on the Quality Control (QC) label for every pixel. If any LAI/FPAR pixel did not meet the quality screening criteria, its value is determined through linear interpolation. However, users cannot get VNP16A2GF in near-real time because it will be generated only at the end of a given year. Provided in the VNP16A2GF product are five variables for composited Evapotranspiration (ET), Latent Heat Flux (LE), Potential ET (PET) and Potential LE (PLE) along with a quality control variable. Two low resolution browse images, ET and LE, are also available for each VNP16A2GF granule. The pixel values for the two Evapotranspiration variables (ET and PET) are the summation of 8-day total water loss within the composite period and the pixel values for the two Latent Heat variables (LE and PLE) are the average total energy over a unit area for a day during the composite period. Note that the last acquisition period of each year is a 5 or 6-day composite period, depending on the year. Known Issues * Please refer to the [VIIRS Land Products website](https://viirsland.gsfc.nasa.gov/Products/NASA/ET_ESDR.html) and [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=VIIRS) for information about VNP16A2GF known issues.

Get the data

vnp16a2gf_access.py

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

results = earthaccess.search_data(
    short_name="VNP16A2GF",
    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.

What's measured

Coverage & cadence

What you can do with it

Get the data

Official links