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Full catalog/N11_AVH02C1
N11_AVH02C1·v6·dataset

Sunlight reflected at the top of the atmosphere (NOAA-11, daily)

NOAA-11 AVHRR Top-of-Atmosphere Reflectance Daily L3 Global 0.05 Deg. CMG
atmosphere NASA LAADS Level 3 HDF-EOS
In plain English

What it measures. How much sunlight the Earth reflects back at the top of the atmosphere each day, as seen across the globe before any correction for haze in the air.

How it's made. Generated from the AVHRR instrument on the NOAA-11 satellite as part of a long-term climate record, gridded daily at about 5 km resolution from an earlier surface-reflectance product.

How & where you'd use it. Part of a decades-spanning climate data record that helps scientists track long-term changes in Earth's land surface and connect older satellite data to newer missions.

What's measured

ATMOSPHERE › ATMOSPHERIC RADIATION › REFLECTANCE › TOP OF ATMOSPHERE (TOA) REFLECTANCELAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › BRIGHTNESS TEMPERATURE

Coverage & cadence

  • Time span1988-11-08 → 1995-01-01
  • Measured byNOAA-11 (AVHRR)
  • Processing levelLevel 3
  • 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 Long-Term Data Record (LTDR) produces, validates, and distributes a global land surface climate data record (CDR) that uses both mature and well-tested algorithms in concert with the best-available polar-orbiting satellite data from past to the present. The CDR is critically important to studying global climate change. The LTDR project is unique in that it serves as a bridge that connects data derived from the NOAA Advanced Very High Resolution Radiometer (AVHRR), the EOS Moderate resolution Imaging Spectroradiometer (MODIS), the Suomi National Polar-orbiting Partnership (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS), and Joint Polar Satellite System (JPSS) VIIRS missions. The LTDR draws from the following eight AVHRR missions: NOAA-7, NOAA-9, NOAA-11, NOAA-14, NOAA-16, NOAA-18, NOAA-19, and MetOp-B. Currently, the project generates a daily surface reflectance product as the fundamental climate data record (FCDR) and derives daily Normalized Differential Vegetation Index (NDVI) and Leaf-Area Index/fraction of absorbed Photosynthetically Active Radiation (LAI/fPAR) as two thematic CDRs (TCDR). LAI/fPAR was developed as an experimental product. The NOAA-11 AVHRR Top-of-Atmosphere Reflectance Daily L3 Global 0.05 Deg. CMG, short-name N11_AVH02C1 is generated from GIMMS Advanced Processing System (GAPS) BRDF-corrected Surface Reflectance product (AVH01C1). The N11_AVH02C1 consist of Top-of-atmosphere reflectance for bands 1 and 2, data Quality flags, angles (solar zenith, view zenith, and relative azimuth), thermal data (thermal bands 3, 4 and 5), and additional data (scan time).

Get the data

n11_avh02c1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="N11_AVH02C1",
    version="6",
    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 LAADS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.