This article on NASA's aging climate satellites incorrectly said that only one satellite in NOAA's POES series is still in orbit. Although a final satellite in the series was recently launched, four others are still in orbit and collecting data.
Scientists' hopes for climate data are up in the air
Shortly after it lifted off in February 2009, NASA's Orbiting Carbon Observatory crashed into the Pacific Ocean near Antarctica. With that, a $250 million investment became scrap metal on the ocean floor and an effort to begin using satellites to measure atmospheric carbon dioxide and trace emission-reduction actions was dealt a huge setback.
Scientists say the information the OCO was intended to collect is a crucial piece of the data needed not only by those monitoring the Earth's environment but also by federal officials struggling to understand possible national security implications of those climate changes.
But the OCO's failure highlighted an even broader problem: Understanding climate change requires a breadth of information on variables from atmospheric carbon dioxide to the condition of Arctic ice, and scientists say that satellites are vital for this. Yet at a time where the massive Larsen B Ice Shelf in Antarctica seems intact one day and then collapses into the sea the next, the system of continuous, reliable satellite observation of Earth is at risk, with some aging satellites in dire need of replacement.
The OCO was "the only satellite in the world that will do the kind of global collection we need," said James Lewis, a senior fellow at the Center for Strategic and International Studies and one of the authors of a 2010 report on satellite monitoring of climate change. "And we haven't thought about how to replace it."
Berrien Moore III, an earth scientist who co-chaired a National Research Council committee several years ago on space-based observation of Earth, said climate change predictions based on mathematical models have failed to capture how quickly sea ice would decline. "Thank God for the [satellite] observations, because otherwise we wouldn't have known this is going on," said Moore, vice president for weather and climate programs at the University of Oklahoma.
A 2005 report by the National Research Council sounded the alarm about the climate satellite system, declaring it was "at risk of collapse," largely because of weakening of U.S. financial support for such programs. The 2010 report by Lewis and others asserted that half of all climate satellites will have outlived their design life within the next eight years.
NASA's earth science budget shrank from about $2 billion to $1.4 billion between 2000 and 2006, when the Bush administration's greater funding priority was space exploration. Several environment-related satellite missions were either cut or shelved:
l The Global Precipitation Measurement mission, designed to replace the 13-year-old Tropical Rainfall Measuring Mission, was delayed from 2010 until at least 2012 during the Bush administration. President Obama's 2011 budget proposes a mid-2013 launch.
l The Landsat series of Earth observation satellites, a nearly 40-year-old mission run by the U.S. Geological Survey, had its next satellite delayed from this year, with the latest plans estimating a 2012 launch. This mission watches rising sea levels, glacial movement and coral reef decline, and it charts environmental conditions for military and intelligence uses. But one of its two satellites is experiencing degraded image quality and the other has been up since 1984, far past its life expectancy.
l The Hydros mission, to measure soil moisture and permafrost, and to improve forecasting of droughts and floods, which was to have been launched this month, was canceled altogether. The Obama administration has proposed a 2014 launch for a satellite to measure soil moisture.
But scientists say the problems for the satellite system started even earlier.
In 1994, President Bill Clinton merged the National Oceanic and Atmospheric Administration's polar-orbiting satellite system with a Defense Department meteorological system. Known as the National Polar-orbiting Operational Environmental Satellite System, or NPOESS, the joint program was to monitor the global climate and Earth and space weather, and was supposed to launch before aging satellites run by NOAA and the Defense Department died. The idea was to maintain continuity of data, eliminate redundancy and save taxpayer money.
More than a decade later, though, the joint program was hemorrhaging money without having left the ground, forcing the Defense Department to reexamine the program. Originally estimated to cost about $6.5 billion through its 24-year life, by 2006 NPOESS's cost estimate was about $12.5 billion, even after critical climate monitoring instruments were cut.
Last April, the Government Accountability Office issued a report that criticized NOAA and the Defense Department for failing to come up with plans to restore the climate-monitoring instruments and warned that there could be major gaps in data as a result.
"The nation won't lose the capability of the scientists being able to say how climate is changing [if there are data gaps], but the scientists will have to say, 'It's changing, but our uncertainty's a little bigger than it was before,' " said Ed Kearns, deputy division chief of the Remote Sensing Applications Division at NOAA's National Climatic Data Center in Asheville, N.C.
NPOESS has still not launched any satellites, and only one of the older orbiters of the NOAA system is still circling the Earth. The Obama administration recently re-split the program into its military and civilian parts in an effort to get it back on track.
"It's all sort of hanging on by a thread, and we need to get these other systems up very soon," said Jeff Privette, program manager of climate data records at NOAA's center in Asheville.
Meanwhile, NASA must rely on limited aircraft surveillance to measure ice sheet thickness in the cryosphere - the Earth's surface where water is in solid form, including sea ice, glaciers and the ice sheets of Greenland and Antarctica - since its Ice, Cloud and land Elevation Satellite (ICESat) failed nearly a year ago. A new version of that satellite, ICESat-2, is planned for launch in 2015, but until then NASA will be limited to three narrower flight-path views, observing only key regions where NASA knows it can't afford to go blind.
"Since the cryosphere is changing so fast right now, we really need to continue those measurements," said Thorsten Markus, ICESat-2 program manager at NASA's Goddard Space Flight Center in Greenbelt.
Given financial constraints, it is unclear what will happen to satellite surveillance of the environment. In its budget request for this year, the Obama administration has proposed increasing NASA's earth science budget to about $1.8 billion, moving it back toward the 2000 level, as the National Research Council recommended in a 2007 report.
For now, the scientists wait and hope.
"When you come right down to it, these are usually â¦ policy decisions," said Kearns. "As scientists, we try to make these requirements and concerns known, and then we kind of hope for the best."
email@example.com Huetteman is a graduate of Northwestern University's Medill School of Journalism. This article is part of the "Global Warming" series, produced by Medill's National Security Reporting Project, on the national security implications of climate change.