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Floods in Indonesia
| Title |
Floods in Indonesia |
| Description |
Days of heavy rains led to devastating landslides on the central Indonesian island of Sulawesi (formerly Celebes) in mid-June 2006. As of June 22, the death toll stood at 200 with 135 still missing, reported the United Nations Office for the Coordination of Humanitarian Affairs. [ http://www.reliefweb.int/rw/RWB.NSF/db900SID/KKEE-6QZME5?OpenDocument ] The hardest hit area was Sinjai in South Sulawesi. This image reflects the rainfall totals over the island from June 14 to June 21, 2006. Highest rainfall totals, on the order of 10 to 12 inches (300 millimeters) are red. The southernmost area of heavy rain is near the southern tip of Sulawesi and covers the higher terrain adjacent to Sinjai. Deforestation in the region is believed to be a contributing factor in the disastrous mudslides. The image was created using data from the Multi-satellite Precipitation Analysis (MPA), which monitors rainfall over the global Tropics. The MPA uses rainfall measurements from the Tropical Rainfall Measuring Mission satellite (TRMM) to calibrate rainfall estimates from other satellites. TRMM's primary mission is to measure rainfall over the global tropics. It was placed into service in November of 1997. From its low-earth orbit, TRMM has been measuring rainfall over the global Tropics using a combination of passive microwave and active radar sensors. TRMM is a joint mission between NASA and the Japanese space agency, JAXA. Image produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC). |
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Floods in Indonesia
| Title |
Floods in Indonesia |
| Description |
Days of heavy rains led to devastating landslides on the central Indonesian island of Sulawesi (formerly Celebes) in mid-June 2006. As of June 22, the death toll stood at 200 with 135 still missing, reported the United Nations Office for the Coordination of Humanitarian Affairs. [ http://www.reliefweb.int/rw/RWB.NSF/db900SID/KKEE-6QZME5?OpenDocument ] The hardest hit area was Sinjai in South Sulawesi. This image reflects the rainfall totals over the island from June 14 to June 21, 2006. Highest rainfall totals, on the order of 10 to 12 inches (300 millimeters) are red. The southernmost area of heavy rain is near the southern tip of Sulawesi and covers the higher terrain adjacent to Sinjai. Deforestation in the region is believed to be a contributing factor in the disastrous mudslides. The image was created using data from the Multi-satellite Precipitation Analysis (MPA), which monitors rainfall over the global Tropics. The MPA uses rainfall measurements from the Tropical Rainfall Measuring Mission satellite (TRMM) to calibrate rainfall estimates from other satellites. TRMM's primary mission is to measure rainfall over the global tropics. It was placed into service in November of 1997. From its low-earth orbit, TRMM has been measuring rainfall over the global Tropics using a combination of passive microwave and active radar sensors. TRMM is a joint mission between NASA and the Japanese space agency, JAXA. Image produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC). |
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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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