The Jason Altimetry Program
Ocean Altimetry: Benefits to the Nation
The Earth’s oceans and atmosphere are inextricably linked. Only from space can we observe the vast oceans on a global scale and monitor critical changes in ocean currents, sea surface height, and heat storage. Since 1992, the TOPEX/Jason series of ocean altimeter satellites has provided precise, global sea level measurements: Jason-2 is the satellite currently on orbit; Jason-3 is scheduled for launch in March 2015 to provide uninterrupted data continuity. These data, in conjunction with data from current and next-generation geostationary and polar-orbiting satellites, are used operationally by government agencies and the private sector, to make more accurate weather predictions over land and ocean, from hurricane intensity forecasting to inter-annual events such as El Niño and La Niña. The bottom line? Ocean weather models will stop functioning if observations are not available, putting lives and property at risk. The following are some of the applications and end users that depend on the ocean weather models that data from Jason makes possible:
The National Hurricane Center uses Jason data to derive ocean heat content to improve hurricane intensity forecasting as much as 3 days in advance. This improved information aids in planning evacuations, thus saving lives and property. (Image: ocean heat content map based on Jason data shows Katrina intensifying to Category 5 hurricane when passing over Loop Current). End Users – National Weather Service (NWS), Federal Emergency Management Agency (FEMA), Department of Homeland Security (DHS), news organizations, state and local disaster managers.
High Wave Warnings
The NWS provides operational high wave warnings in the open ocean based in part on Jason observations that save lives and property. End Users – USCG, U.S. Navy, NWS, commercial ship operators, cruise ship operators, commercial fisherman, offshore oil platform operators, Federal and State coastal managers.
El Niño/La Niña Seasonal Forecasting
The NWS uses Jason observations to initialize seasonal El Niño/La Niña forecasts which provide early warnings of droughts in some regions and excessive precipitation elsewhere. End Users – NWS, DHS, Department of the Interior, news organizations, State and local disaster managers, agriculture sector, wildland fire community.
Jason-derived surface currents are also used in ecosystem models to help scientists and policy makers understand how changes in the environment affect fish stocks. End Users – National Marine Fisheries Service, State agencies, Sea Grant Institutions, ROFFS, management councils.
Ocean Hypoxia Dead Zones
Multi-decade declines in oxygen (hypoxia) have been observed in the coastal waters off the West Coast and Gulf of Mexico, causing serious disruption to the marine environment. The phenomena are influenced by air and water-borne pollution and changing ocean circulation patterns monitored and investigated with ocean models initialized with Jason observations. End Users – Federal and State coastal managers, academia, Sea Grant Institutions.
Resilient Coastal Communities and Economies:
Search and Rescue
The U.S. Coast Guard (USCG) Search & Rescue (SAROPS) uses Jason surface currents to plan search patterns for life saving operations. Knowing the currents allows the USCG to narrow- down search zones, improving response times, saving lives, property, and operational costs. End Users – Federal and state agencies, and private companies.
Off-shore oil platform operators rely on Jason high current warnings to avoid accidents during sensitive operations, such as lowering or raising drill strings. Knowing the predicted paths of energetic ocean eddies allows operators to schedule activities to reduce the risk of a major equipment accident or environmental disaster. End Users – oil industry and private oceanographic service providers.
Oil Spill Response
Information on surface currents, collected by the Jason satellites, are used to predict the movement of oil spills, making it possible to respond quickly and effectively. End users – Federal agencies (e.g., NOAA, FEMA, EPA), state agencies, and private oceanographic service providers.
Global and Regional Sea Level Rise
The now 22 year record of altimetry data shows sea level rising at about 3 mm/year, nearly twice as fast as during the last century. The global rate of sea level rise has been estimated to be approximately 2/3 due to ice melt and 1/3 due to ocean warming (i.e., thermal expansion). These increases place coastal and low lying communities at risk during storm surge. End Users – Federal, state, and local coastal managers, IPCC, academia.
Jason-derived surface currents are used by recreational and commercial fishermen to minimize fish search time and boat operating costs. In addition, the fishing sector also uses maps of the seafloor (bathymetry) that are produced with data collected by Jason. End Users – private oceanographic service providers.
Energy Siting Purposes
Jason-derived surface currents are used in the siting of off-shore facilities, like oil platforms and ocean wind power farms. End users – Federal agencies (e.g., NOAA, FEMA, EPA), state agencies, and private oceanographic service providers.