One of the more controversial environmental issues, which emerged in the final years of the Soviet era, was the plan to dam and reverse the flow of north-flowing rivers in order to irrigate the dry southern steppes. This scheme was roundly criticised by scientists and environmentalists at the time because of fears for the impact on the Arctic Ocean and global climate. It now appears that nature performed this experiment some 90,000 years ago.
This months issue of the Journal of Quaternary Science reports evidence based on years of fieldwork in Siberia by Professor Jan Mangerud, of the University of Bergen, Norway, which indicates that early in the last Ice Age, natural ice dams formed and drastically altered the drainage patterns of the region.
At the start of the ice age an ice sheet formed over the shallow Barents and Kara seas forming a natural dam. As the ice advanced onto the Siberian mainland, it blocked the flow of the northerly flowing rivers, including the Yenissei, Ob, Pechora and Dvina, which supply most of the Arctic Ocean with its freshwater. Huge ice-dammed lakes were formed which covered massive areas of Siberia. One of these on the western Siberian Plain was more than twice as large as any lake on Earth today. The overflows from these lakes were towards the south, into the Aral, Caspian and Black seas which were also connected by large rivers. The drainage of the Eurasian continent was thus reversed.
Joanna Gibson | alphagalileo
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Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
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Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
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For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
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An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
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A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
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