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Hidden river once flowed beneath Antarctic ice
August 21, 2017 05:46 PM - Rice University

Antarctic researchers from Rice University have discovered one of nature’s supreme ironies: On Earth’s driest, coldest continent, where surface water rarely exists, flowing liquid water below the ice appears to play a pivotal role in determining the fate of Antarctic ice streams.

The finding, which appears online this week in Nature Geoscience, follows a two-year analysis of sediment cores and precise seafloor maps covering 2,700 square miles of the western Ross Sea. As recently as 15,000 years ago, the area was covered by thick ice that later retreated hundreds of miles inland to its current location. The maps, which were created from state-of-the-art sonar data collected by the National Science Foundation research vessel Nathaniel B. Palmer, revealed how the ice retreated during a period of global warming after Earth’s last ice age. In several places, the maps show ancient water courses — not just a river system, but also the subglacial lakes that fed it.

Ancient Italian Fossils Reveal Risk of Parasitic Infections Due to Climate Change
July 20, 2017 03:15 PM - University of Missouri

In 2014, a team of researchers led by a paleobiologist from the University of Missouri found that clams from the Holocene Epoch (that began 11,700 years ago) contained clues about how sea level rise due to climate change could foreshadow a rise in parasitic trematodes, or flatworms. The team cautioned that the rise could lead to outbreaks in human infections if left unchecked. Now, an international team from Mizzou and the Universities of Bologna and Florida has found that rising seas could be detrimental to human health on a much shorter time scale. Findings from their study in northern Italy suggest that parasitic infections could increase in the next century, if history repeats itself.

How the Arctic Ocean Became Saline
June 6, 2017 10:28 AM - Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research

The Arctic Ocean was once a gigantic freshwater lake. Only after the land bridge between Greenland and Scotland had submerged far enough did vast quantities of salt water pour in from the Atlantic. With the help of a climate model, researchers from the Alfred Wegener Institute have demonstrated how this process took place, allowing us for the first time to understand more accurately how Atlantic circulation as we know it today came about. The results of the study have now been published in the journal Nature Communications.

Por qué los ríos del mundo están perdiendo sedimentos y por qué es importante
June 29, 2017 07:13 AM - Jim Robbins, YaleEnvironment360

En septiembre de 2011, después de 20 años de planificación, se inició la desmantelación de las represas Elwha y Glines en el río Elwha, en el noroeste del estado de Washington. En aquel momento, era el proyecto más grande de remoción de presas en la historia de los Estados Unidos, y tomó casi tres años para que ambas barreras fueran desmanteladas y para que el río volviera a fluir libremente.

A lo largo de sus casi cien años de vida, las dos represas recolectaron más de 24 millones de metros cúbicos de sedimento detrás de ellos, lo suficiente para llenar el estadio de los halcones Marinos de Seattle ocho veces. Y desde su remoción, el Elwha ha recuperado el sedimento atrapado y lo ha distribuido río abajo, haciendo que el ecosistema ribereño sea reconstruido y transformado. Se han llevado a la costa grandes cantidades de limo, arena y grava, resucitando un ecosistema de humedales largamente privado de sedimentos.

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