Soft release of two SNPP VIIRS and two NOAA-20 VIIRS Nighttime Lights products

The LAADS DAAC has executed a soft release of four Nighttime Lights products. A soft release means that users can directly access and download these data products but cannot search for or discover them via the LAADS DAAC's search and order interface or through the Earthdata portal. Users may access and download these four data collections via the following URLs referenced in their shortnames:

1. SNPP VIIRS Daily at-Sensor Top-of-Atmosphere Nighttime Lights (VNP46A1)
2. SNPP VIIRS Daily Moonlight-adjusted Nighttime Lights (VNP46A2)
3. NOAA-20 VIIRS Daily at-Sensor Top-of-Atmosphere Nighttime Lights (VJ146A1)
4. NOAA-20 VIIRS Daily Moonlight-adjusted Nighttime Lights (VJ146A2)

The above v2.0 collections contain certain changes and differences relative to the previous v1.0 collection. They include the following:

1. The v2.0 Day-Night Band (DNB) radiance data format has changed from unsigned integer in v1.0 to floating-point format to prevent saturation in cases such as extremely bright gas flares with radiance values exceeding 6553.5 nW·cm⁻²·sr⁻¹. The maximum value for an unsigned integer format is 65535.
2. The v1.0 VNP46A2 collection is produced exclusively for land surfaces, whereas v2.0 VNP46A2 is generated for both land and water surfaces.
3. In the v2.0 collection, the VNP46A2 Mandatory_Quality_Flag layer has been updated to 0 for high quality and 1-5 for poor quality. Besides, the v2.0 Mandatory_Quality_Flag includes additions for lunar eclipse (qa=3), aurora (qa=4), and glint (qa=5). In v1.0, the Black Marble products are generated with solar zenith angles greater than 108 degrees. In the new v2.0, the range is expanded to include solar zenith angles greater than 102 degrees. Also, the quality for solar zenith angles between 102 and 108 degrees is assigned a value of 2 in the Mandatory_Quality_Flag.
4. The SNPP VIIRS DNB experienced degradation after launch, whereas the NOAA-20 and NOAA-21 VIIRS DNB remain stable. In v2.0, the yearly DNB spectral response functions are applied to the SNPP VIIRS Black Marble product.

Consult the v2.0-specific Black Marble User Guide for additional details.

If you have any questions, contact the LAADS User Services.