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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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Volcanic Plume from Mount Se
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| Title |
Volcanic Plume from Mount Semeru, Java |
| Description |
On the Island of Java, Indonesia, Mount Semeru released a volcanic plume on May 3, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] took this picture the same day. This image shows the opaque, gray-beige plume blowing toward the west over the island of Java. Scattered around the volcano are bright white clouds.Semeru [ http://www.volcano.si.edu/world/volcano.cfm?vnum=0603-30= ] is a stratovolcano composed of alternating layers of solidified lava, hardened ash, and volcanic rocks. In part of a larger pattern of seismic activity on Java, the volcano erupted [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=13607 ] in 2006. You can download a 250-meter-resolution Semeru KMZ file [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/May2007/semeru_tmo_2007123.kmz ] for use with Google Earth. [ http://earth.google.com/download-earth.html ] NASA image created by Jesse Allen, using data provided courtesy of the MODIS Rapid Response [ http://rapidfire.sci.gsfc.nasa.gov/ ] team. |
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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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