Worldview Adds 15 New Data Layers

Worldview, NASA's interactive web-based imagery mapping and visualization application, added several new data layers from NASA's Plankton, Aerosol, Cloud ocean Ecosystem (PACE) satellite, which launched in February 2024; the Joint Polar Satellite System (JPSS) NOAA-20 and NOAA-21 satellites; and the ESA (European Space Agency) Sentinel-3A and -3B satellites.

Although Worldview already offers several data layers that include ocean color, nighttime lights, corrected reflectance, and similar views (including existing layers from NOAA-20), the addition of new layers from PACE, NOAA-21, and Sentinel-3A and -3B expands Worldview's offerings from different satellites and increases the number of Earth observations at different times of day.

New Data Layers

Chlorophyll a Data Layers from PACE, NOAA-20 and -21, and Sentinel-3A and -3B

The concentration of chlorophyll a is used as an index of phytoplankton biomass, a measurement scientists use as a general assessment of ocean health, as changes in the amount of phytoplankton indicate changes in ocean productivity.

• The Level 2 Chlorophyll a data layer from PACE provides the near-surface concentration of chlorophyll a in milligrams of chlorophyll pigment per cubic meter (mg/m³) in the ocean. The Chlorophyll a product is available from PACE’s Ocean Color Instrument (OCI), a spectrometer used to measure the intensity of light over portions of the electromagnetic spectrum: ultraviolet (UV), visible, near infrared, and several shortwave infrared bands. The imagery resolution is 1 km, and the temporal resolution is daily.
• The Chlorophyll a data layers from NOAA-20 and NOAA-21 provide the near-surface concentration of chlorophyll a in mg/m³. The layers are created with data from the satellites' Visible Infrared Imaging Radiometer Suite (VIIRS) instruments, the imagery resolution is 1 kilometer, and the temporal resolution is daily. The temporal coverage for the NOAA-20 layer is December 13, 2017, to the present; the temporal coverage for the NOAA-21 layer is March 31, 2023, to the present.
• The Chlorophyll a data layers from Sentinel-3A and -3B provide the near-surface concentration of chlorophyll a in mg/m³. The layers are created with data from the satellites' Ocean and Land Colour Instruments (OLCI), imagery resolution is 1 kilometer, and temporal resolution is daily. Temporal coverage of the Sentinel-3A layer is April 25, 2016, to the present; temporal coverage of the Sentinel-3B layer is May 14, 2018, to the present.

The addition of these layers complements the existing chlorophyll a layers available from the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments aboard the Aqua and Terra satellites and the VIIRS instrument aboard the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite.

Corrected Reflectance True and False Color Data Layers from PACE and NOAA-21

Corrected Reflectance imagery was developed to provide natural-looking images by removing gross atmospheric effects such as Rayleigh scattering from the visible bands of satellite sensors. As a result, these images are often referred to as "true" or "natural" color because the combination of wavelengths used to produce them yields natural-looking images of land surface, oceanic, and atmospheric features that appear similar to what the human eye would see. In contrast, false-color imagery omits the use of natural colors and enlists bands outside the visible spectrum of light to facilitate the detection of surface and atmospheric features that may be difficult to discern, such as ice and clouds.

• The PACE Corrected Reflectance (True Color) data layer combines data from the red (610 nanometer), green (555 nm), and blue (465 nm) channels of the OCI sensor. OCI enables the continuous measurement of light at finer wavelength resolution than previous NASA ocean color sensors, thereby providing detailed information on the global ocean. The imagery resolution is 1 kilometer and the temporal resolution is daily.
• The NOAA-21 Corrected Reflectance (True Color) imagery layer uses data from the green, blue, and red bands from the VIIRS instrument aboard NOAA-21 to create natural-looking images of land surface, oceanic, and atmospheric features similar to what the human eye would see. Its resolution is 250 meters, the temporal resolution is daily, and the temporal coverage is April 19, 2024, to the present.
• The NOAA-21 Corrected Reflectance False Color (M11-I2-I1) imagery layer uses data from three bands (M11-I2-I1) on NOAA-21's VIIRS instrument to create imagery useful for distinguishing burn scars from naturally low vegetation or bare soil and for enhancing flood detection. This combination of bands can also be used to distinguish snow and ice from clouds. Thick ice and snow appear vivid sky blue, while small ice crystals in high-level clouds will appear blueish; water clouds will appear white.
• NOAA-21 Corrected Reflectance False Color (M3-I3-M11) imagery layer uses data from three bands (M3-I3-M11) of NOAA-21's VIIRS instrument to create imagery used to map snow and ice. This combination of bands is also good for distinguishing liquid water from frozen water (e.g., clouds over snow, ice clouds versus water clouds).

These layers complement the existing Corrected Reflectance layers available from the MODIS instruments aboard the Aqua and Terra satellites and the VIIRS instrument aboard the Suomi NPP and NOAA-20 satellites.

Photosynthetically Available Radiation (PAR) Data Layers from NOAA-20 and NOAA-21

Photosynthetically available radiation (PAR) refers to the amount of light available for photosynthesis, which is in the 400 to 700 nanometer spectral range.

• The Photosynthetically Available Radiation (Level 2) data layers from the NOAA-20 and NOAA-21 satellites display the amount of photosynthetically available radiation over the ocean and large bodies of water and is measured in Einstein/m²/day. The layers are created with data from the satellites' VIIRS instruments. The temporal coverage of the NOAA-20 data layer is December 13, 2017, to the present, whereas the temporal coverage of the NOAA-21 data layer is March 21, 2023, to the present. (Note: An Einstein is a unit of energy used in photobiology to measure the amount of light energy absorbed by a substance.)

These layers complement the existing PAR layers available from the MODIS instruments aboard the Aqua and Terra satellites and the VIIRS instrument aboard the Suomi NPP satellite.

Black Marble Nighttime at Sensor Radiance and Black Marble Nighttime Blue/Yellow Composite (Day/Night Band) Data Layers from NOAA-20

The ultra-sensitivity of the VIIRS instrument's Day/Night Band enables scientists to capture Earth's surface and atmosphere in low light conditions, thereby allowing for better monitoring of nighttime phenomena. These images are also useful for assessing anthropogenic sources of light emissions under varying illumination conditions. For instance, during partial to full moon conditions, the layer can identify the location and features of clouds and other natural terrestrial features such as sea ice and snow cover, while enabling temporal observations in urban regions, regardless of moonlit conditions. As such, the layer is particularly useful for detecting city lights, lightning, auroras, fires, gas flares, and fishing fleets.

• The Black Marble Nighttime At Sensor Radiance (Day/Night Band) data layer from NOAA-20 is created from NASA's Black Marble daily at-sensor top-of-atmosphere nighttime radiance product. It is displayed as a grayscale image and is "stretched," which results in improvements in capturing city lights in greater spatial detail as compared to some traditional nighttime imagery. The imagery resolution is 500 meters, and the temporal resolution is daily. Temporal coverage is March 25, 2024, to the present.
• The Black Marble Nighttime Blue/Yellow Composite (Day/Night Band) data layer from NOAA-20 offers nighttime city lights in shades of yellow and nighttime cloud presence in shades of blue, thereby aiding before and after comparisons of areas over time or after periods of significant change, such as the growth of metropolitan areas, natural disasters, for other factors that may change the amount of emitted light. The imagery resolution is 500 meters, and the temporal resolution is daily. Temporal coverage is March 18, 2024, to the present.

These layers complement the existing Black Marble layers available from the VIIRS instrument aboard the Suomi NPP satellite.

Brightness Temperature Data Layers from NOAA-21

NOAA-21 Brightness Temperature data from Band I5 of the satellite's VIIRS instrument provides brightness temperature observations measured in Kelvin (K), calculated from the top-of-the-atmosphere radiances. It does not provide an accurate temperature of either clouds or the land surface, but it does show relative temperature differences that can be used to distinguish features both in clouds and over clear land, and land, sea ice, and open water over the polar regions during winter (in cloudless areas).

• The NOAA-21 VIIRS Day and Night Brightness Temperature data layers are calculated from VIIRS Calibrated Radiances. The imagery resolution is 250 meters and the temporal resolution is daily. Temporal coverage for both layers is from April 19, 2024, to the present.

These layers complement the existing Brightness Temperature layers available from the MODIS instruments aboard the Aqua and Terra satellites and the VIIRS instruments aboard the Suomi NPP and NOAA-20 satellites.

Orbit Track Data Layers from PACE, NOAA-21, and Sentinel-3A and -3B

Orbit path data layers show the path of a particular satellite on its ascending and descending orbits.

• The PACE Ascending/Day and Descending/Night Orbit Track and Time data layers show the path of the PACE satellite on its ascending/day and descending/night orbits. Overpass times for both the ascending and descending orbits are shown in Coordinated Universal Time (UTC). Temporal coverage for both products is February 8, 2022, to the present.
• The NOAA-21 Ascending/Day and Descending/Night Orbit Track and Time data layers show the path of the NOAA-21 satellite on its ascending/day-time and descending/nighttime orbit. Local overpass time at the equator is approximately 13:30 in the day and the local overpass time at the equator is approximately 01:30 during the night. Overpass times for both layers are shown in UTC and their temporal coverage is November 10, 2022, to present.
• The Sentinel-3A Ascending/Night and Descending/Day Orbital Track and Overpass Time data layers show the path of the Sentinel-3A satellite on its ascending/nighttime and descending/daytime orbits. Overpass times for both the ascending and descending orbits are shown in UTC. Temporal coverage for both products is February 16, 2016, to the present.
• The Sentinel-3B Ascending/Night and Descending/Day Orbital Track and Overpass Time data layers show the path of the Sentinel-3B satellite on its ascending/nighttime and descending/daytime orbits. Overpass times for both the ascending and descending orbits are shown in UTC. Temporal coverage for both products is April 25, 2018, to the present.

About NASA Worldview

Since its release in December 2011, the systems engineers and developers supporting Worldview have strived to make it the premiere web-based application for the interactive browsing of global, full-resolution satellite imagery. The addition of data layers from new missions like PACE and from NASA's national and international partners including NOAA and ESA are a testament to the Worldview team's ongoing commitment to that goal.

"Worldview is a great place to discover and explore visualizations of NASA satellite imagery," said Minnie Wong, a systems engineer with NASA's Earth Science Data and Information System (ESDIS) Project. "It can be used to monitor natural phenomena as they're happening, observe change over time with imagery from past decades, and it provides useful ways for users to interact with the imagery—all within the application. Further, if users are interested in the data underlying the visualizations, Worldview will connect them to Earthdata Search so they can download the data and analyze the data on their own."

Developed by NASA's Earth Observing System Data and Information System (EOSDIS), Worldview lets users interactively explore more than 1,000 global, full-resolution satellite imagery layers provided through NASA's Global Imagery Browse Services (GIBS). In addition, many of the imagery layers available in Worldview are updated within three hours of observation, essentially showing Earth as it looks "right now," which benefits time-critical applications such as wildfire management, air quality monitoring, and flood surveillance.

Adding Data Imagery Layers

To add layers to the Worldview basemap, click the orange “Add Layers” button at the bottom of the layer list, as identified in the image below.

Clicking the "Add Layers" button will open a large window called the layer picker that allows users to search for data layers by category or keyword. In the image below, "PACE" has been entered into the search bar at the top of the window. To view a particular data layer (or layers) on the map, users must click on the orange checkbox next to the layer and then close the window by clicking on the "x" in the top right corner.

For additional information on using Worldview, see the recent Data Tool in Focus article that provides a basic overview of how users can harness the capabilities of NASA Worldview to discover, visualize, and download NASA Earth science data.

Learning Resources

The NASA Earthdata website has several in-depth presentations and other learning resources available to help users make the most of Worldview. In addition, there is a Feedback link in the Worldview menu under the information button that allows users to pose questions directly to the Worldview team.

• Tutorial: Introduction to Worldview
• Tutorial: Getting Started with NASA Worldview (December 2021)
• Webinar: NASA Worldview—Explore the Earth from Past to Present with Global Satellite Observations (May 2021)
• Animated GIF Tutorial: View and Share Your Planet with Worldview (April 2020) Tutorial en Espanol
• How to Use Worldview (PDF) (November 2019)