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Mitigating Gaps in Weather Satellite Data

This information appears as published in the 2017 High Risk Report.

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The two federal agencies responsible for managing weather satellites, the Department of Commerce’s National Oceanic and Atmospheric Administration (NOAA) and the Department of Defense (DOD), are in different stages in their efforts to ensure continued weather satellite coverage in their respective satellite orbits. In recognition of NOAA’s significant progress, we have narrowed the scope of this high-risk area to remove the segment on NOAA’s geostationary weather satellites. At the same time, we are expanding this high-risk area to include a segment on DOD’s polar-orbiting weather satellites because the agency has been slow to replace aging satellites and, as a result, is at risk of a gap in weather satellite data in the early morning orbit. We did not include a segment on DOD weather satellites in our prior high-risk update because the department was not, at that time, facing an imminent satellite data gap.[1]

The United States relies on two complementary types of satellite systems for weather observations and forecasts: (1) polar-orbiting satellites that provide a global perspective every morning and afternoon, and (2) geostationary satellites that maintain a fixed view of the United States. Both types of systems are critical to weather forecasters, climatologists, and the military, who map and monitor changes in weather, climate, the oceans, and the environment. Federal agencies are currently planning or executing major satellite acquisition programs to replace existing polar and geostationary satellite systems that are nearing the end of, or beyond, their expected life spans. Specifically, NOAA is responsible for the polar satellite program that crosses the equator in the afternoon and for the geostationary satellite program, while DOD is responsible for the polar satellite program that crosses the equator in the early morning orbit. However, these programs have troubled legacies of cost increases, missed milestones, technical problems, and management challenges that have reduced functionality and delayed launch dates. As a result, the continuity of weather satellite data is at risk.

NOAA officials acknowledge that there is a risk of a gap in polar satellite data in the afternoon orbit, between the time that the current polar satellite is expected to reach the end of its life and the time when the next satellite is expected to be in orbit and operational. This gap could span up to a year or more, depending on how long the current satellite lasts and whether there are any delays in launching or operating the new one.[2] In addition, there is a risk of a gap in polar satellite data in the early morning orbit because DOD has not yet replaced satellites that are nearing the end of their life spans. While NOAA does not anticipate gaps in geostationary satellite observations, such a gap could occur if the satellites currently in orbit do not last as long as anticipated or if the major satellite acquisition currently underway encounters schedule delays.

According to NOAA program officials, a satellite data gap would result in less accurate and timely weather forecasts and warnings of extreme events—such as hurricanes, storm surges, and floods. Such degraded forecasts and warnings would endanger lives, property, and our nation’s critical infrastructures. Similarly, according to DOD officials, a gap in space-based weather monitoring capabilities could affect the planning, execution, and sustainment of U.S. military operations around the world. Given the criticality of satellite data to weather forecasts, the likelihood of significant gaps, and the potential impact of such gaps on the health and safety of the U.S. population and economy, we concluded that the potential gap in weather satellite data is a high-risk area and added it to the High-Risk List in 2013. It remained on the High-Risk List in 2015.

For this high-risk update, we are both narrowing and expanding the high-risk area. We are narrowing this high-risk area to remove NOAA’s geostationary weather satellite program because the agency improved its gap mitigation contingency plans and made substantial progress in ensuring it had the capacity to integrate and test the next satellite, called the Geostationary Operational Environmental Satellite-R (GOES-R) series. Moreover, the agency successfully launched this satellite in November 2016 and is now better able to ensure continuous satellite coverage.

In contrast, we are expanding the high-risk area to include a segment on DOD’s polar-orbiting satellite program, which provides weather observations in the early morning orbit. The department has been slow to establish plans for its follow-on satellite program and has made little progress in determining how it will meet selected weather satellite requirements in the early morning orbit. Moreover, DOD is currently relying on an older satellite that is well past its expected life span. As a result, there is a real risk of a weather satellite data gap in the early morning orbit. Such a gap could negatively affect military operations that depend on weather data.


[1] In our February 2013 high-risk update, we noted that DOD had two weather satellites that it planned to launch. These satellites, called the Defense Meteorological Satellite Program (DMSP)-19 and 20, were planned for launch in 2014 and 2020. By our February 2015 high-risk update, DOD had successfully launched DMSP-19 and was still planning to launch DMSP-20. However, the continuity of DOD satellite data has become less assured since that time. The DMSP-19 satellite stopped providing data in February 2016. Further, DOD halted its plans to launch DMSP-20 after the department did not certify that it would launch the satellite by the end of calendar year 2016. DOD is now relying on an older satellite for data in that early morning orbit.

[2] In our February 2013 high-risk update, we reported that—instead of the 18- to 24-month gap that NOAA anticipated—the gap could span from 17 to 53 months or more, depending on how long the current satellites last and whether there are any delays in launching or operating the new one. In October 2013, NOAA officials reported that the gap could be as short as 3 months because of the relatively strong performance of the current satellite and their plan to reduce the expected length of the next satellite’s on-orbit checkout period. However, we noted that the gap could occur sooner and last longer than NOAA anticipated if the launch date was delayed, the on-orbit checkout period took longer than anticipated, or space debris caused the current satellite to fail early. In October 2016, NOAA determined that it would need to delay the launch of the next satellite by 4 to 6 months to address issues in the development of the ground system. As a result, the potential for a gap remains.

Mitigating Gaps in Weather Satellite Data

The two federal agencies responsible for managing weather satellites, NOAA and DOD, are in different stages in their efforts to ensure continued weather satellite coverage in their respective satellite orbits. NOAA’s efforts to strengthen mitigation planning for its polar-orbiting satellites in the afternoon orbit have resulted in it meeting three of the five criteria for removal from the high-risk area: leadership commitment, capacity, and monitoring progress. Specifically, NOAA has demonstrated leadership commitment in mitigating data gaps on its polar-orbiting weather satellites by establishing gap mitigation action plans, improving its computing capacity, and monitoring progress in implementing multiple mitigation activities. However, the agency has not yet addressed key shortfalls in its gap mitigation plans and several mitigation projects are not yet complete. Moreover, the agency recently decided to delay the launch date of the next polar-orbiting satellite due to problems in development. These issues increase the likelihood of a data gap in the afternoon orbit. The agency’s efforts to further improve its gap mitigation plans, complete gap mitigation projects, and successfully launch the next polar satellite will help ensure that it is in a good position to mitigate the possibility of gaps in satellite data.

Regarding its geostationary satellites, NOAA’s efforts to strengthen mitigation planning have resulted in it meeting all five of the criteria for removal from the high-risk area. Specifically, NOAA has demonstrated leadership commitment in acquiring the next geostationary satellite, developing and implementing mitigation plans, and monitoring the health of the satellite constellation. In addition, NOAA and the National Aeronautics and Space Administration (NASA) successfully launched the latest geostationary weather satellite in November 2016, a step which improved the agency’s ability to ensure robust satellite coverage. In recognition of the agency’s significant progress, we have narrowed the scope of this high-risk area to remove the segment on NOAA’s geostationary satellites.

On the other hand, DOD has been slow to establish a new satellite program, selected high-priority capabilities are not addressed by the department’s planned program, and problems with existing satellites have increased the risk of a gap in satellite data in the early morning orbit. In October 2016, over 6 years after the department was directed to establish a program to launch new satellites in the early morning orbit, DOD established a plan for its Weather Satellite Follow-on—Microwave program. The department plans to launch the first operational satellite under this program in 2022. However, this program does not address two high-priority capabilities—cloud characterization and area-specific weather imagery—and the department has not yet determined how it will provide those capabilities. Further, DOD’s primary satellite in the early morning orbit failed in February 2016, and the department is now using an older satellite that is well past its expected life span. Until the department launches its next satellite and establishes a plan to provide the two high-priority capabilities, it faces a significant risk of a gap in satellite data should the existing operational satellite fail. As a result of DOD’s limited progress in developing and implementing a plan to fulfill its weather satellite requirements, we are expanding this high-risk area to include a segment on DOD’s progress in addressing the need for satellite coverage in the early morning orbit.

Over the last 4 years, congressional committees have held multiple hearings to address this high-risk area. Examples include:

  • Subcommittees of the House Science, Space, and Technology Committee have held multiple hearings to provide oversight of major satellite acquisitions and the risk of gaps in satellite coverage (September 2013, February 2015, December 2015, July 2016) and on private sector weather forecasting (May 2015, June 2016).
  • In March 2016, the Subcommittee on Commerce, Justice, Science, and Related Agencies of the Senate Appropriations Committee held a hearing on the President’s fiscal year 2017 budget proposal that included a discussion of current and future satellite programs.
  • In July 2016, the House Science, Space, and Technology Committee’s Subcommittee on Environment held a hearing to provide oversight of DOD’s efforts to plan a new satellite acquisition and address the potential for gaps in satellite coverage.

Also over the last 4 years, Congress has worked on legislation to address this high-risk area. Examples include:

  • The Weather Research and Forecasting Innovation Act of 2015 was introduced as a bill in the House of Representatives to advance programs and activities related to improving weather warnings and forecasts—including analysis of potential observing system gaps—and clarifying NOAA’s ability to access commercial weather data and products.[1]
  • Congress appropriated funds for satellite data gap mitigation activities through the Disaster Relief Appropriations Act, 2013.[2]

[1] See H.R.1561 - Weather Research and Forecasting Innovation Act of 2015 — 114th Congress (2015-2016). The House committee report includes an extensive discussion related to commercially provided weather data. This bill passed the in the House and Senate, but the Senate made changes and sent it back to the House on December 2, 2016.

[2] See supplemental enacted to provide assistance for relief of Hurricane Sandy: Public Law 113-2, Disaster Relief Appropriations, containing Division A: Disaster Relief Appropriations Act, 2013 and Division B: Sandy Recovery Improvement Act of 2013.

Additional Details on What GAO Found are in the full report.

NOAA’s Weather Satellites

NOAA has made considerable progress over the last 2 years, particularly in mitigating the risk of a geostationary satellite data gap and in improving its capacity to mitigate polar-orbiting satellite data gaps. NOAA demonstrated leadership commitment, improved its high-performance computing capacity, developed gap mitigation plans, and successfully launched a geostationary weather satellite in November 2016. As a result, we are narrowing our high-risk area to remove the segment on NOAA’s geostationary weather satellites. However, NOAA’s polar-orbiting weather satellites remain on the High-Risk List because more remains to be done before the remaining two criteria can be met. NOAA needs to address the shortfalls we identified in its gap mitigation plans and to demonstrate progress in key gap mitigation projects. Specifically, NOAA needs to

  • address residual shortfalls in its mitigation plan, including providing key information about the cost and effects of the mitigation options, and establishing when the testing of selected options would be completed (this is a recommendation that we identified as a priority recommendation to the Secretary of Commerce); and
  • demonstrate progress by completing the remaining gap mitigation projects identified in the polar satellite gap mitigation plan, including addressing the technical challenges that delayed the scheduled launch date for the next satellite, deciding when the next satellite will be launched, and acting to ensure a timely and successful launch.

DOD’s Polar-Orbiting Weather Satellites

DOD has made limited progress in its efforts to replace aging satellites and is now at risk of a gap in weather satellite data in the early morning orbit. As a result, we are expanding this high-risk area to include DOD’s polar-orbiting weather satellites. The department needs to

  •  demonstrate progress on its next generation of weather satellites, called the Weather System Follow-on—Microwave (WSF-M) program, to address the risk of a gap in the early morning orbit; and
  • establish and implement plans to mitigate the risk of a gap in the high-priority capabilities that are not included in WSF-M .
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