The southern Aral Sea has been deemed beyond salvaging, and the restoration effort will instead focus on the much smaller, but less polluted and saline, northern sea (top right). Recent hydrographic surveys have revised downward the lifespan of the dying lake complete desiccation could happen in as few as 15 years. The image at right was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite on August 12, 2003, and it shows the rapid retreat of the Sea's southern half, now separated into a western and eastern half, both of which may face the same bleak future. What water makes its way back to the Sea is increasingly saline and polluted by pesticides and fertilizer. As the agricultural land becomes contaminated by the salt, the farmers try to combat it by flushing the soil with huge volumes of water. Dust storms increased, spreading the salty soil right into the agricultural lands. The drying out of the Sea's southern part exposed the salty seabed. The diversion process began in the 1960s, and by 1989, Landsat satellite imagery (left image) showed that the northern and southern half of the sea had already become virtually separated. The southern part of the Sea was fed by the Amurdar'ya and the northern part was fed by the Syrdar'ya, forming a large inland lake that moderated the region's continental climate and supported a productive fishing industry. Once the fourth largest lake on Earth, the Aral Sea has shrunk dramatically over the past few decades as the primary rivers that fed the Sea have been diverted and tapped nearly dry for cotton farming and other agriculture. In July 2003, the Kazakhstan government, with funding from the World Bank, began a massive restoration project for the Aral Sea. /images/imagerecords/3000/3730/aral_sea_12aug03_250m.jpg AugAqua MODIS scene at 250 m resolution (276 k JPEG).The SOHO mission is being conducted collaboratively between the European Space Agency and NASA. This affected radio communication frequencies that either pass through the ionosphere to satellites or are reflected by it to traverse the globe. X-ray and ultraviolet light from the flare changed the structure of the Earth's electrically charged upper atmosphere (ionosphere). The classification measures the disruption in radio communications. An R4 blackout, rated by the NOAA SEC, is second to the most severe R5 classification. Monday's solar flare produced an R4 radio blackout on the sunlit side of the Earth. The increase of particles at this energy level still poses no appreciable hazard to air travelers, astronauts or satellites, and the NOAA SEC rates this radiation storm as a moderate S2 to S3, on a scale that goes to S5. The flare and solar ejection has also generated a storm of high-velocity particles, and the number of particles with ten million electron-volts of energy in the space near Earth is now 10,000 times greater than normal. Severe solar weather is often heralded by dramatic auroral displays, northern and southern lights, and magnetic storms that occasionally affect satellites, radio communications and power systems. Depending on the orientation of the magnetic fields carried by the ejection cloud, Earth-directed coronal mass ejections cause magnetic storms by interacting with the Earth's magnetic field, distorting its shape, and accelerating electrically charged particles (electrons and atomic nuclei) trapped within. ![]() Coronal mass ejections are clouds of electrified, magnetic gas weighing billions of tons ejected from the Sun and hurled into space with speeds ranging from 12 to 1,250 miles per second. ![]() Solar ejections are often associated with flares and sometimes occur shortly after the flare explosion. Caused by the sudden release of magnetic energy, in just a few seconds flares can accelerate solar particles to very high velocities, almost to the speed of light, and heat solar material to tens of millions of degrees. Solar flares, among the solar system's mightiest eruptions, are tremendous explosions in the atmosphere of the Sun capable of releasing as much energy as a billion megatons of TNT. Luckily, the flare was not aimed directly towards Earth. This recent explosion from the active region near the sun's northwest limb hurled a coronal mass ejection into space at a whopping speed of roughly 7.2 million kilometers per hour. The flare was definitely more powerful than the famous solar flare on March 6, 1989, which was related to the disruption of power grids in Canada. EDT, on Monday, April 2, 2001, the sun unleashed the biggest solar flare ever recorded, as observed by the Solar and Heliospheric Observatory (SOHO) satellite. View an /images/imagerecords/1000/1331/superflare.mov animation from the Extreme ultraviolet Imaging Telescope (EIT).
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