The Visible Infrared Imaging Radiometer Suite (VIIRS) collects global observations of land, atmosphere, cryosphere and oceans in visible and infrared wavelengths. The VIIRS Imagery Viewer hosts 7 days’ worth of imagery over North America — refreshed daily — for all 22 VIIRS channels ranging from wavelengths of 0.41 micrometers (μm) to 12.01 μm. Five of these channels are high-resolution image bands called I-Bands, and sixteen are moderate-resolution bands or M-Bands. This viewer also hosts Day Night Band (DNB) images with unique nighttime perspectives. CIMSS acquires the data from the Suomi-NPP and NOAA-20 polar-orbiting satellites. VIIRS data is available to anyone with a Direct Broadcast antenna and can be processed using open source software made freely available by NOAA and CIMSS.
Our iconic rooftop can be seen for miles around Madison. We’re often asked about the “radar dome” which is actually a satellite dish within a protective canvas cover. This is our Direct Broadcast antenna. (fun fact: the base is the old radar tower from NWS Madison!) As new images become available from Suomi-NPP and NOAA-20, they are downloaded to this antenna, processed via CSPP software, and made available in a thumbnail directory via this VIIRS Imagery Viewer, usually within 60 minutes of being acquired onboard the spacecraft! Current and archived images over the continental USA are also available on the VIIRS TODAY website. As future JPSS VIIRS satellites join the fleet, that data will also be available on these sites.
Day Night Band (DNB) images
VIIRS instruments include a unique band that is sensitive to very small amounts of visible light over a broad spectral region called the Day Night Band (DNB) which can detect visible light at night by leveraging reflected moonlight and terrestrial and atmospheric sources that emit visible light. Features that can be seen at night using this band include clouds and bright land surfaces (snow) at or near full moon, as well as city lights, fires, lightning and the aurora borealis. How much each of these features can be discerned is dependent on moon phase and lunar rise and set times for any given calendar date.
True Color and False Color images
Along with individual bands, this site features multiple Level-2 products. The most popular are True and False Color images. VIIRS True Color imagery is a combination of M-Bands 3, 4 and 5 (Blue (0.48 µm), Green (0.55 µm) and Red (0.67 µm)) and are absolutely stunning. False Color combines M-Bands 11 and 12 with I-Band 1.
Both VIIRS Today and this Direct Broadcast VIIRS Imagery Viewer host True and False Color images. This site also features several other Level-2 products such as MIRS and CLAVR-X cloud products and AF active fire products. Another advantage of this site is that it hosts full overpass images so coverage extends much further north, enabling unique and often spectacular views of the Aurora Borealis.