A Delta 2 rocket blasted off on a balmy Friday morning at Vandenberg Air Force Base, delivering a revolutionary tool to observe ocean levels globally and collect data that will help improve weather and climate forecasts.

The United Launch Alliance rocket departed at

12:46 a.m. from Space Launch Complex-2 and climbed into mostly clear skies that let spectators track the flight for several minutes.

An hour later, ground controllers confirmed the $432 million Ocean Surface Topography Mission (OSTM), or Jason 2, had successfully arrived in orbit, after a camera on board the booster provided incredible video of the craft gently floating away.

Jason 2, a joint mission involving NASA and France, will continue collecting data on sea levels from space, measurements that have many practical applications, according to Eric Lindstrom, OSTM/Jason 2 program scientist at NASA Headquarters.

Two previous satellites have collected similar data since 1992, although the new craft boasts much more advanced instruments.

“Measuring sea level from 830 miles from space with errors of a few inches is not just cool science, it's really a critical application for everybody on the planet,” Lindstrom said.

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Data collected from earlier satellites such as Jason 1 is available on the Web, and used by more than just oceanographers. Lindstrom recalls how roofers in California called when officials were late releasing one cycle of maps during the 1997-98 El Nino season. Those roofers had used satellite data to determine the outlook for their industry.

Scientists are interested in sea level spikes because they are connected to global climate change.

“The ocean really behaves like a natural thermostat regulating our climate,” said Lee-Lueng Fu, OSTM/Jason 2 project scientist at Jet Propulsion Laboratory in Pasadena. “Without the ocean, our atmosphere would be much warmer.

“However, when the ocean warms, its water expands, and raises sea level. Furthermore the melting of the ice dumps water into the ocean and also raises sea level.”

Since satellites began taking sea-height measurements, levels have risen 3 millimeters a year, Fu said.

“This sounds (like) a very small number to you, but this is in fact twice the rate of sea levels estimated from sparsely located tidal gauges over the preceding 100 years,” Fu said. “So the question facing us is whether this apparent acceleration is a real trend caused by global warming or it is simply part of the natural variability of our climate system.

“We don't really know the answer. That's why we need continuing satellite measurement like OSTM/Jason 2 to extend this data record into the future.”

While some uncertainty remains, an international panel on global warming estimates rising sea levels could inundate many coastal zones of Florida and the Gulf States, Fu added.

“Therefore it's crucial for us to keep a close eye on the changing sea levels, not only for potentially catastrophic impacts, but also to help scientists like us to develop better predictive models so we can project sea level rise into the future and help mitigate the impact,” Fu said.

Using the data allows better forecasting of hurricanes, which feed off the heat energy created over the ocean surface and intensify, according to Laury Miller, chief scientist for the National Oceanic Atmospheric Administration Lab for Satellite Altimetry.

Scientists have used data retrospectively and found they could reduce hurricane intensity forecasting errors by as much as 20 percent, and see a maximum improvement as far out as 96 hours before the storm would hit land.

“This clearly is an important step forward in our ability to forecast, accurately, hurricanes,” Miller said.

The mission will be helpful for many other applications, according to scientists.

OSTM/Jason 2's capabilities will improve the ability to forecast ocean currents, which can lead to better planning for what routes ships should take, ultimately saving fuel and improving efficiency of sea transport, according to Mikael Rattenborg, director of operations for European Organization for the Exploitation of Meteorological Satellites or Eumetsat.

While the 1,153-pound satellite appears to be in its proper place in space, engineers will analyze data after spotting some potential performance problems with the rocket.

“It seemed like the first stage went a little short and it looks like the second stage had to make up for some of that,” said Omar Baez, NASA launch director. “This is a high-performance mission. In other words it's a very light spacecraft for this type of rocket, Maybe it's nothing but we do have to look at the data a little bit.”

Janene Scully can be reached at 739-2214 or janscully@santamariatimes.com

June 21, 2008