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Green Blog: Report Points to Risk of Serious Gap in Weather Satellite Data

A new report from the Government Accountability Office elevates the problem of looming gaps in satellite weather data to a ?high risk? concern for the federal government

The G.A.O.?s high-risk report, updated every two years to coincide with each new Congress, focuses on federal programs that provide essential public services, often at great cost, but operate with a pronounced ineffectiveness or inefficiency.

Areas like Medicare, military contracting and tax law enforcement have resided on the list continuously since its inception in 1990. The relatively low-profile addition of weather satellites last week underscores growing concerns about short-term and midrange satellite weather observations and forecasts in the United States and across the globe.

The report notes that the United States relies on two types of satellite systems for observations and forecasts: polar-orbiting satellites that provide a global perspective every morning and afternoon and geostationary satellites that maintain a fixed view of the United States. Federal agencies are currently involved in efforts to replace systems of both types that are approaching the end of their estimated life spans.

?However, these programs have troubled legacies of cost increases, missed milestones, technical problems and management challenges that have resulted in reduced functionality and slips to planned launch dates,? the G.A.O. report says. ?As a result, the continuity of satellite data is at risk.?

J?r?me Lafeuille, chief of the World Meteorological Organization?s space observation program, warned in an interview that if a satellite failed before a new system was in place, forecasting could be seriously impeded.

?It?s not that you wouldn?t have anything,? he said, ?but you could lose something like 35 or 40 percent of the input data for the models.?

A report released in December by the European Center for Medium-Range Weather Forecasts said that without data from satellites like those operated by the United States, forecasts would have projected that Hurricane Sandy would be hundreds of miles out to sea on the evening of Oct. 29. Instead, the models were able to predict five days beforehand that Sandy would make landfall on that evening.

The growing potential for a data gap, which the Government Accountability Office says could range from 17 to 53 months, is chiefly attributed to launch delays for the next-generation satellite programs.

The Joint Polar Satellite System, for example, is being designed to replace a temporary satellite with a nominal life span of three to five years that was launched in October 2011. Taking the most optimistic view, this demonstration satellite will run until October 2016.

Yet the first J.P.S.S. satellite is not scheduled for launching until March 2017 and will not be fully operational until a year after that. ?This is where we get the 17-month estimate,? David A. Powner, an information technology expert who oversaw the satellite portion of the audit, said in an interview.

In testimony last month before Congress, Mr. Powner described the potential gap as a ?crisis? arising from ?a long history of cost overruns, technical problems, and mismanagement.?

The most pessimistic estimate, a 53-month data gap, is based on the possibility that the current satellite cuts out after only three years, in the fall of 2014, and the J.P.S.S. launch is delayed one year, a reasonable assumption given the program?s record.

?The goal of the J.P.S.S. program is much more ambitious than the previous generations,? Mr. Lafeuille noted, and pushing cutting-edge technologies can expose a project to risks of delay.

?To be ambitious, not overambitious, not underambitious ? this is a very delicate question,? he said.

Yet Stephen English, a satellite section head at the European Center for Medium-Range Weather Forecasts, said the system could prove more resilient than the report indicates. ?Satellites don?t generally work fine, and then one day suddenly fail,? he said.

Rather, data collection undergoes a slow process of degradation. The NOAA-15 satellite launched in 1998, for example, continues to collect and send data today, although the quality has diminished over time by about half.

?If you assume the satellite up there now survives only its nominal lifetime, then, yes, we probably are looking at a data gap,? Dr. English said. ?But if you assume it lasts about the average lifetime of satellites from the past 10 to 15 years, then we?ve got a good chance of actually bridging that gap.?

The report nonetheless recommends that the National Oceanic and Atmospheric Administration, which along with NASA is responsible for J.P.S.S., should act to minimize any risks of a gap. In a Sept. 18 memo, Jane Lubchenco, NOAA?s chief, outlined the basics of such a mitigation plan.

In the end, although often seen as a platform for rebuke, the high-risk list is meant ?to be helpful,? Mr. Powner said. ?Our intent is to do work and make recommendations that ultimately help agencies get off the list.?

Source: http://green.blogs.nytimes.com/2013/02/18/report-sees-risk-of-serious-satellite-data-gaps/?partner=rss&emc=rss

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