LUXEMBOURG — Europe’s weather satellite organization, Eumetsat, is asking its members to finance 18 percent of a $900 million, two-satellite ocean-altimetry program that will follow on from existing missions financed by France and the United States and, more recently, by Eumetsat as well.

The 30-nation Eumetsat, based in Darmstadt, Germany, is funding the new mission, called Jason-CS for Continuity of Service, as an optional program, meaning nations contribute as they see fit.

With substantial French and German interest in Jason-CS, and given the success of the previous Jason missions, securing the needed funding should be feasible even at a time when many Eumetsat governments are struggling financially, Eumetsat Director-General Alain Ratier said.

As a Eumetsat optional program, Jason-CS needs 90 percent of the estimated total financial commitment of 130 million euros ($160 million) before it can proceed. Eumetsat will ask its member governments in June for contributions to the program.

Eumetsat plans to take a 23 percent share of the European government contribution to Jason-CS, with the 20-nation European Space Agency and the European Commission paying the remaining 77 percent. The U.S. National Oceanic and Atmospheric Administration is expected to complete the package by contributing three sensors to the satellites as well as the launch services.

Eumetsat continues to have difficulty finding the 3.2 billion euros needed for the Metop Second Generation polar-orbiting meteorological satellite system. At the Eumetsat council meeting Nov. 26, the agency came up with about 87 percent of the required commitment.

In a Dec. 1 interview, Ratier said that while he had hoped for a full program commitment, several Eumetsat members have new governments following elections, and the incoming administrations want to review spending. He said Eumetsat’s ruling council had authorized the start of Metop Second Generation as soon as 95 percent of the required funding was committed. This, he said, should occur by next spring.

Six of Eumetsat’s 30 governments — Belgium, Lithuania, Portugal, Romania, Slovenia and Spain — have withheld their formal commitment to Metop Second Generation up to now, accounting for the 13.3 percent shortfall in commitments.

Ratier said the only concrete deadline for Metop Second Generation, in terms of Eumetsat’s investment, is the expected mid-2015 start of satellite hardware construction. Airbus Defence and Space in October was awarded a 1.7 billion-euro contract to build the six Metop Second Generation satellites. Eumetsat and ESA are jointly funding the first two satellites’ construction.

ESA and the European Commission are backing Jason-CS as part of their multibillion-euro Copernicus environment-monitoring network. NOAA is expected to seek about $200 million to launch the Jason-CS satellites in 2021 and 2025 and provide three sensors for each of the spacecraft.

The Jason ocean-altimetry program began as a joint research effort by NASA and the French space agency, CNES. As the user community expanded, NOAA and Eumetsat were added as partners.

At the commission, Jason-CS is referred to as Sentinel 6 and is part of the Sentinel series of Copernicus satellites.

NASA and CNES have begun work on a separate, next-generation altimetry mission called Surface Water and Ocean Altimetry (SWOT), with a planned launch in 2020 and a budget estimated at $900 million combining the French and U.S. investments.

The NASA and CNES work is in keeping with these organizations’ focus on research and development, which was the status of basic ocean altimetry before the two agencies joined to build the Topex-Poseidon satellite, launched in 1992.

Since then, ocean altimetry — and with SWOT, the coverage is extending to small inland waterways — has been conducted through the Jason satellites.

The most recent, Jason-2, was launched in June 2008 and is now passed its nominal retirement date. Its main computer has failed, forcing operations teams to rely on the backup system. Ratier said Jason-2 teams are investigating whether a software patch can be sent to the satellite to repair the main computer.

Jason-3 was supposed to be launched this year but NOAA’s budget issues, tied to the overall U.S. government budget difficulties, have delayed the launch until next spring. NOAA in July 2012 signed an $82 million contract with SpaceX, formally known as Space Exploration Technologies Corp., of Hawthorne, California, to launch Jason-3 aboard a Falcon 9 rocket operated from Vandenberg Air Force Base, California.

In a Dec. 4 response to SpaceNews inquiries, NOAA said it could not comment on a prospective Jason-CS budget. For Jason-3, NOAA said it is committed to launching it and would “do everything possible to maintain the launch this year,” meaning the fiscal year that ends next Sept. 30.

Peter B. de Selding was the Paris bureau chief for SpaceNews.