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Images of Indonesia and Jet Propulsion Laboratory (JPL) from 2006
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Storms in the Java Sea
| Title |
Storms in the Java Sea |
| Description |
A ferry carrying more than 600 passengers sank in the Java Sea between the islands of Borneo (image center) and Java (to the south-southwest) just before midnight on December 29, 2006, during high winds and rough seas. On January 1, 2007, a plane carrying more than 100 people crashed on its flight over the Java Sea, high winds and turbulent weather are being investigated as possible causes. The origin of surges of deadly wind in this usually relatively calm region are poorly understood, and the area is not well-monitored with traditional weather equipment. Ocean winds data from NASA's QuikScat satellite may help improve monitoring and understanding of unusual weather in the area. Data obtained from QuikScat on December 30 and January 1 shed new insights into the atmospheric conditions at the time of the tragic incidents described above. In this image from January 1, the different colors reveal different wind speeds. White arrows are wind vectors showing both direction and speed. The data from December 30 and January 1 showed that the strong winds in the Java Sea originated from the surge of a strong winter monsoon from the Asian continent. The monsoon winds blew south across the South China Sea and deflected eastward after they crossed the equator due to the rotation of Earth. The winds in the Java Sea remained strong through January 1, 2007. Associated with the eastward winds, twin cyclones were also observed by QuikScat. (A cyclone is any large-scale atmosphere circulation around a region of low air pressure. The systems spin counter-clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.) The stronger cyclone was south of the equator (summer hemisphere) between Java and Australia, and a weaker one was north of the equator (winter hemisphere) west of Borneo. QuikScat measures ocean surface wind speed by sending radar pulses to the surface and measuring the strength of the signals that return to the sensor. The sensor's wide-scale observations make it possible for scientists to interpret local weather events, such as the recent high wind outbreak in the Java Sea region, in the context of the large-scale atmospheric circulation and to confirm connections between the two. QuikScat data are available in near-real time to operational weather forecasting agencies around the world. NASA image courtesy of David Long, Brigham Young University, on the QuikSCAT Science Team, [ http://winds.jpl.nasa.gov/ ] and the Jet Propulsion Laboratory. |
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Jason Satellite Observes Mil
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nasa, nasaimageofthedaygalle
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In September 2006, NASA sate
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ElNino_JAS_20060915
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-09-15 |
| creator |
NASA -- NASA image by Akiko Hayashi, Jet Propulsion Laboratory. |
| identifier |
ElNino_JAS_20060915 |
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Jason Satellite Observes Mil
…
nasa, nasaimageofthedaygalle
…
In September 2006, NASA sate
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ElNino_JAS_20060915
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-09-15 |
| creator |
NASA -- NASA image by Akiko Hayashi, Jet Propulsion Laboratory. |
| identifier |
ElNino_JAS_20060915 |
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QuikScat Shows Rough Seas/At
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PIA09110
Sol (our sun)
SeaWinds Scatterometer
| Title |
QuikScat Shows Rough Seas/Atmospheric Conditions at Time of Two Java Sea Disasters |
| Original Caption Released with Image |
. QuikScat is managed for NASA's Science Mission Directorate, Washington, DC, by NASA's Jet Propulsion Laboratory, Pasadena, CA. JPL also built the SeaWinds radar instrument and is providing ground science processing systems. NASA's Goddard Space Flight Center, Greenbelt, MD, managed development of the satellite, designed and built by Ball Aerospace & Technologies Corp., Boulder, CO. The National Oceanic and Atmospheric Administration has contributed support to ground systems processing and related activities., A ferry carrying more than 600 passengers sank in the Java Sea between the island of Java and Borneo just before midnight on December 29, 2006, during high winds and rough seas. On January 1, 2007, a plane carrying more than 100 people crashed on its flight over the Java Sea, high winds and turbulent weather are being investigated as possible causes. The origin of surges of deadly winds in this usually relatively calm region is poorly monitored and understood. However, ocean winds data from NASA's QuikScat satellite show potential for helping alleviate such deficiencies. Data obtained from QuikScat on December 30 and January 1 shed new insights into the atmospheric conditions at the time of these incidents. QuikScat data are available in near real time to operational weather forecasting agencies around the world. The data from December 30 and January 1 observed that the strong winds in the Java Sea originated from the surge of a strong winter monsoon from the Asian continent. The monsoon winds blew south across the South China Sea and deflected eastward after they crossed the equator due to the rotation of Earth. The winds strengthened as they were channeled through the land masses of Indonesia. The winds in the Java Sea remained strong through January 1, 2007. Associated with the eastward winds, twin cyclones (a counter-clockwise circulation in the Northern Hemisphere and a clockwise circulation in the Southern Hemisphere) were also observed by QuikScat, the stronger one was south of the equator (summer hemisphere) between Java and Australia, and a weaker one was north of the equator (winter hemisphere) west of Borneo. In this image from January 1, the different colors denote different wind speeds. White arrows are wind vectors showing both direction and speed. The large-scale, broad and simultaneous observations by QuikScat make it possible to put the local weather into the context of the large-scale circulation, and confirm one of the assumptions that links the cold surge of the Asian monsoon with tropical cyclones in the western Pacific. QuikScat, managed by JPL, measures ocean surface wind/stress by sending radar pulses to the surface and measuring the strength of the signals returned. "QuikScat Background" NASA's Quick Scatterometer (QuikScat) spacecraft was launched from Vandenberg Air Force Base, California on June 19, 1999. QuikScat carries the SeaWinds scatterometer, a specialized microwave radar that measures near-surface wind speed and direction under all weather and cloud conditions over the Earth's oceans. More information about the QuikScat mission and observations is available at http://winds.jpl.nasa.gov [ http://photojournal.jpl.nasa.gov/catalog/PIA09110 http://winds.jpl.nasa.gov ] |
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Jason Satellite Observes Mil
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PIA01939
Sol (our sun)
Altimeter
| Title |
Jason Satellite Observes Mild El Nino in 2006 |
| Original Caption Released with Image |
In September 2006, NASA satellite data indicated that El Niño had returned to the tropical Pacific Ocean, although it was relatively weak. As of early October, scientists were not sure if the event would persist, and it was much less intense than the last major El Niño episode, which happened in 1997-1998. That event brought devastating floods to California that cost millions of dollars in damage while severe drought struck Indonesia, Australia, and the Philippines. Among the ocean characteristics that signal developing El Niño events is a change in average sea surface height compared to normal sea level. When water warms, it expands a little, which changes its volume slightly. When heat begins to build up in the Pacific during an El Niño event, the sea surface height begins to creep up. NASA observes changes in average sea surface height using its Jason satellite. The image is based on the average of 10 days of data centered on September 15, 2006, compared to the long-term average of observations from 1993-2005. In this image, places where the Pacific sea surface height is higher (warmer) than normal are yellow, orange, and red, and places where the sea surface is lower (cooler) than normal are blue and purple. Green shows where conditions are near normal. The swath of red in the center of the scene reveals that an El Niño was in progress when Jason observed the Pacific. El Niño is a cyclical warming of the ocean waters in the central and eastern tropical Pacific that generally occurs every 3 to 7 years. It is linked with changes in air pressure and high-level winds that can affect weather worldwide. Typically peaking during the Northern Hemisphere winter months, El Niño is the warm phase of the El Niño/Southern Oscillation. It alternates with La Niña, the cooling of ocean waters in the same region of the Pacific. According to Bill Patzert, oceanographer and climatologist at NASA's Jet Propulsion Laboratory, "The present conditions indicate that the intensity of this El Niño is too weak to have a major influence on current weather patterns. But, if the ocean waters continue to warm and spread eastward, this event would likely strengthen, perhaps bringing much-needed rainfall to the southwestern and southeastern United States this winter." The Jason satellite carries a dual-frequency radar altimeter. This instrument beams microwave pulses-at 13.6 and 5.3 Gigahertz, respectively-downward toward the Earth. To determine the ocean's height, the instrument precisely measures the time it takes for the microwave pulses to bounce off the surface and return to the spacecraft. This measure, multiplied by the speed of light, gives the range from the satellite to the ocean surface. The joint U.S.-French Topex/Poseidon mission is managed by the JPL for NASA's Science Mission Directorate, NASA Headquarters, Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena. Research on Earth's oceans using Jason and other, space-based capabilities is conducted by NASA's Science Mission Directorate to better understand and protect our home planet. For more information on NASA's ocean surface topography missions, see http://sealevel.jpl.nasa.gov/ [ http://sealevel.jpl.nasa.gov/ ] or to view the latest Jason data see http://sealevel.jpl.nasa.gov/science/jason1-quick-look/ [ http://sealevel.jpl.nasa.gov/science/jason1-quick-look/ ]. |
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