GeoXO Ocean Color Instrument (OCX)

NOAA plans to include a hyperspectral, ultraviolet through near-infrared passive imaging radiometer that analyzes ocean data as part of the GeoXO satellite system. The GeoXO Ocean Color (OCX) instrument is planned to achieve 300-meter (984-foot) spatial resolution.

OCX will provide up to hourly observations of ocean biology, chemistry, and ecology to assess ocean productivity, ecosystem change, coastal and inland water quality, seafood safety, and hazards like harmful algal blooms (HABs). Hourly observations will show daily changes in ocean biology and rapid coastal ocean dynamics. The instrument will also track and assist in the response to climate-driven ocean and coastal ecosystem changes.

Improvements Over Current Capabilities

Image of the cloud coverage over the Western United States

Caption: Of the 17 days shown in the animation above, only 30-35% (5-6 day) have sufficient data to resolve oceanic dynamics. Geostationary ocean color would provide significantly greater daily spatial coverage. Credit: NOAA NFMS

Having an ocean color instrument onboard a geostationary satellite like GeoXO will provide a comprehensive view of the U.S. Economic Exclusive Zone (EEZ) and Great Lakes that is impossible to achieve from ships. NOAA defines an EEZ as an area of the ocean, generally extending 200 nautical miles (230 miles) beyond a nation's territorial sea, within which a coastal nation has jurisdiction over both living and nonliving resources. NOAA is mandated to support the stewardship of 479 fish stocks and 164 endangered and threatened species throughout the 3.4 million square mile U.S. EEZ.

High-resolution OCX observations will be an improvement over the once-per-day observations offered by current low-Earth orbiting ocean color sensors. From its position in geostationary orbit, OCX will view ocean and coastal conditions more frequently and greatly improve the chance of cloud-free observations of areas of interest. Cloud cover is an issue over the nation’s most valuable fisheries, protected species populations, and coastal communities. Hourly ocean color images from geostationary orbit can mitigate the effect of cloud cover over these areas.

With fast image updates, OCX promises to mitigate cloud cover issues over the U.S. Pacific coral reefs. Today, NOAA can image only one out of five coral reefs due to cloud cover. This impacts NOAA’s ability to manage reef systems, such as the Hawaiian Coral Reefs, valued at $33.57 billion.

OCX will have a higher spectral resolution than the Joint Polar Satellite System (JPSS) Visible Infrared Imaging Radiometer Suite (VIIRS), allowing a better understanding of water clarity and chlorophyll concentration as well as detection of harmful algal blooms and coastal pollutants. The finer spatial resolution of OCX compared to JPSS VIIRS and NASA's Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission will allow for monitoring water quality of smaller bodies of water and closer to the coast.

Benefits of a Geostationary Ocean Color Instrument

OCX observations will support ecological forecasters, marine resource managers, fisheries, health departments, water treatment managers, and the commerce, recreation, and tourism industries.

Public Health

OCX observations will contribute to NOAA forecasts of HABs. NOAA monitors conditions daily and issues forecasts for HABs in support of the tourism industry and public health, including respiratory issues.

Operational Land Imager (OLI) satellite image of western Lake Erie algal bloom on July 31, 2015. Image credit: NASA

Commercial and Recreational U.S. Fisheries

OCX will provide better predictions and scientific advice for decision-making about valuable sustainable fisheries and protected resources. Early warning would allow for mitigation to protect shellfish stocks and ensure public health safety.

Improved Data Resolution

The instrument’s 300-meter (984-foot) spatial resolution will help NOAA provide more accurate and timely forecasts and scientific guidance to federal, state, and local agencies about rapidly emerging coastal hazards such as harmful algal blooms.

Improved Determination of Phytoplankton Functional Types

OCX data will provide new indicators of ecosystem production, refine estimates of the overall fisheries yield, and advance HAB forecasting.

Improved Timing of Harmful Algal Bloom Events

It is estimated that the acute health effects associated with marine pathogens and HAB toxins cost almost $1 billion per year. Improved ecological forecasts improve mitigation and decision-making, reducing both costs and effects of events and longer-term changing conditions. Improved forecasts provide more time for mitigation and predicting when conditions will return to normal (e.g. allowing shellfish closures to be lifted as quickly and safely as possible).

Improved Ecological Forecasts

OCX will provide improved ecological forecasts for state fisheries, state health departments, water treatment managers, local commerce and tourist industries, and recreational and commercial fisheries and shellfisheries.

Monitoring Land-Based Pollution

Land-based sources of pollution (LBSP) from coastal development, deforestation, agricultural runoff, and oil and chemical spills produce many serious coral reef ecosystem stressors, most notably toxicants, sediments, and excess nutrients. These can impede coral growth and reproduction, disrupt overall ecological function, and cause disease and mortality in sensitive species. LBSP is typically caused by coastal and upstream land development (but can also form from natural land erosion). It is identifiable by a significant increase in water turbidity (the measure of relative clarity of a liquid), especially following significant precipitation events that result in plume events. Ocean color data is used to track LBSP by identifying plume signatures, which helps identify health threats to coral reef ecosystems. With the improved temporal (hourly) and spatial (300 m) resolutions OCX will offer, scientists and watershed managers will see LBSP events unfold and could respond more quickly, leading to more effective response rates.

NOAA’s land-based sources of pollution value chain

OCX Value Assessment Report

Learn more about the benefits of geostationary ocean color observations in NOAA’s Technical Report: The Value of Geostationary Ocean Color.

OCX Status

On May 26, 2022, NASA selected Ball Aerospace & Technologies Corp. of Boulder, Colorado, and Raytheon Intelligence & Space of El Segundo, California, to conduct OCX Phase A Studies. Each company is conducting a twenty-month definition-phase study of a geostationary ocean color instrument.