Tuesday, August 5, 2008

Ocean Surface Topography Mission/Jason 2 Begins Mapping Oceans

Ocean Surface Topography Mission/Jason 2 Begins Mapping Oceans

July 30, 2008
PASADENA, Calif. – Less than a month after launch, the NASA-French space agency Ocean Surface Topography Mission (OSTM)/Jason 2 oceanography satellite has produced its first complete maps of global ocean surface topography, surface wave height and wind speed.

The new data will help scientists monitor changes in global sea level and the distribution of heat in the ocean. This information is used to monitor climate change and ocean circulation, and to enable more accurate weather, ocean and climate forecasts. The data reveal patterns of sea level anomalies, which are used by scientists to calculate the speed and direction of ocean surface currents.

The new mission extends a 16-year continuous record of global sea level measurements begun in 1992 by the NASA/Centre National d'Etudes Spatiales (CNES) Topex/Poseidon mission and continued by the two agencies on Jason 1, launched in 2001. Data from Topex/Poseidon and Jason 1 show that mean sea level has been rising by about three millimeters (.12 inches) a year since 1993.

The new maps were generated from the first 10 days of data collected once the new satellite, OSTM/Jason 2, reached its operational orbit of 1,336 kilometers (830 miles) on July 4. The new satellite and its predecessor, Jason 1, are now flying in formation in the same orbit approximately 55 seconds apart, making nearly simultaneous measurements that are allowing scientists to precisely calibrate the new satellite's instruments. Comparisons of data from the two satellites on sea-level anomalies, significant wave height and ocean wind speed all show very close correlation of all measured parameters.

"These initial observations from OSTM/Jason 2 compare very closely to those of Jason 1," said Lee-Lueng Fu, OSTM/Jason 2 project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "To be able to collect such high-quality science data within a month of launch breaks previous records. It is also a direct reflection of how mature the field of satellite altimetry has become and of the seamless cooperation of our international team."

The satellite's first radar altimeter data were acquired just 48 hours after its launch on June 20 from Vandenberg Air Force Base, Calif., on a Delta II rocket. The French space agency processed the first test results, followed by more advanced data results a week after launch. The more advanced results came after calculating the precise location of the satellite's preliminary orbits. The satellite, its instruments and ground segment are all functioning properly. Once it has been fully calibrated and validated, the satellite will begin providing oceanographic products to users around the world.

OSTM/Jason 2 is an international endeavor, with responsibilities for satellite development and launch shared between NASA and CNES. CNES provided the OSTM/Jason 2 spacecraft, NASA provided the launch, and NASA and CNES jointly provided the primary payload instruments. CNES and the U.S. National Oceanic and Atmospheric Administration (NOAA) are responsible for satellite operations, while JPL is managing the mission for NASA. Data processing is being carried out by CNES, the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) and NOAA, depending on the type of product.

Once on-orbit commissioning of OSTM/Jason 2 is completed, CNES will hand over mission operations and control to NOAA, which will then join with EUMETSAT to generate, archive and distribute data products to users worldwide.

For more information about OSTM/Jason 2, visit: http://www.nasa.gov/ostm .

JPL is managed for NASA by the California Institute of Technology in Pasadena.


Severe storms rattle Chicago, suburbs

Thunderstorm watch remains; tornado reported in Elmhurst

By Dan P. Blake and Steve Schmadeke

Chicago Tribune reporters

10:56 PM CDT, August 4, 2008

A line of severe thunderstorms moved through the Chicago area Monday night, downing trees and power lines, starting fires, briefly closing down both Chicago airports and delaying a Cubs game.

A tornado warning that was in effect for Will, DuPage and Cook Counties expired at 8:45 p.m., but a severe-thunderstorm watch remained until early Tuesday morning, according to the National Weather Service.

Weather service officials said they were compiling multiple damage reports Monday night and had no immediate reports of injuries.

A trained spotter reported a tornado touched down in Elmhurst, weather service officials said, but Elmhurst officials said the report was incorrect. "There was no tornado that touched down," said Elmhurst Police Sgt. Bob Tannehill. "We just had some heavy winds come through the area—some trees down, nothing major, and some downed power lines."

Elmhurst authorities said the minor damage was not confined to any single area of town. No injuries were reported.

Officials in Schiller Park also said a report of a tornado touching down there was incorrect, though the town did suffer wind damage. There was a report of a fire sparked by a lightning strike in Batavia.

About 8 p.m. in downtown Chicago, a calm, warm, humid evening turned into a frightening lashing of wind and strong rains. Tornado sirens could be heard at Wrigley Field, where the Cubs game was delayed because of the heavy rain and lightning.

Thousands of fans were evacuated to the stadium's concourse. Officials warned fans through a public address system and on the scoreboard to get into the lower levels of the stadium, but thousands remained in their seats.

Several fans ran out onto the field and slid on the rain tarp before being pulled away.

There was heavy tree damage in south Maywood and Broadview. Many roads were impassable because of the fallen tree branches.

"This happened so fast," said Broadview resident Roberta McGill, who was taking pictures of a large tree branch that fell on the parkway outside their home. She and her daughter, Nia McGill, 14, saw the skies turn black and green and quickly headed to the basement to wait out the storm. "We hate to lose that tree. That's a lot of shade."

A couple of blocks away in Broadview, Azariah Israel arrived home just after the storm to find a large branch from a backyard tree down across his deck. "It could have been worse," he said.

Now is time to prepare for natural disasters

The Salinas Californian

Monterey County emergency response officials say Tuesday's 5.4-magnitude earthquake in Southern California underscores the need to stay prepared for major temblors and other natural disasters in our own region.

Earlier this year, scientists calculated that California faces a 99.7 percent chance of a magnitude-6.7 quake or larger in the next 30 years.

Lynda Maguet, disaster director for the local chapter of the American Red Cross, said residents should keep a fully stocked disaster kit that includes food and water that can last for 72 hours, a radio, batteries, whistle and personal hygiene kit.

Residents also should have a "life file" card on the refrigerator. The card should include health information such as medications, illnesses and contact information for family members and friends, Maguet said.

"It is important to be prepared," she said. "When we had the big earthquake in '89 here, I thought I was prepared, but I wasn't."

Four fault systems can be found in Monterey County: San Andreas, Palo Colorado-San Gregorio, Nacimiento and Monterey Bay faults, said Phil Yenovkian, the county's emergency services planner. Only the San Andreas fault is capable of producing a significant event, he said.

"Earthquakes are something we all have to learn to live with in California," he said.

"We will never be free of that threat."

First State Bank in Parkersburg, Iowa, released surveillance video that shows a house being ripped apart by a tornado on May 25, 2008


Man rescued from raft on Lake Michigan

Gannett Wisconsin Media

SHEBOYGAN -- A man floated a mile out into Lake Michigan and had to be rescued after the wind caught his raft this afternoon, according to the Sheboygan County Sheriff’s Department.

The man, whose identity was not immediately available, was in the water with his son just off Blue Harbor Resort and Conference Center when the wind sent him off a sandbar and out into the lake, Sgt. Doug Tuttle said. The man was diabetic and unable to paddle or swim in himself.

The incident occurred about 12:30 p.m.

Family members alerted the U.S. Coast Guard, but a sheriff’s department boat responded because the Coast Guard craft was not in port, Tuttle said.

Tuttle advised beachgoers to keep in mind that winds typically blow out over the lake and can pick up quickly.