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Antarctica ice shelves are rapdily melting as we speak. – Middle East Headlines

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The greater part the ice racks ringing Antarctica that keep gigantic ice sheets from sliding into the sea and lifting ocean levels are in danger of disintegrating. It is all because of environmental change, scientists said Wednesday.

Antarctica Ices’ Fierce cracking

Soften water running into profound gaps brought about by warming air is sabotaging the auxiliary honesty of these common blockades. Researchers are particularly worried about the debilitated condition of ice racks keeping down West Antarctica’s Pine Island and Thwaites ice sheets which could, whenever destabilized, raise worldwide seas by multiple meters. The two icy masses spread a region bigger than Germany. As much as a kilometer thick, ice racks are the strong ice augmentation of land-bound ice sheets.

Since they are now coasting on sea water, they don’t add to the ocean level. Even when immense pieces sever as ice sheets. Be that as it may, the unmistakably more enormous icy masses hinder from sliding toward the ocean. They have just become a significant supporter of ocean level ascent. The United Nation’s science warning board for environmental change, the IPCC, has figure that seas will ascend to a meter before the century’s over.

Countless individuals live inside a couple of meters of ocean level. Ice racks are frequently wedged between land arrangements. For example, at the mouth of a narrows. It encourages them oppose the weight of the ice sheets pushing toward the ocean. In any case, environmental change is dissolving them in a larger number of ways than one.

Global Action Required

Prior examination has appeared than warming sea water is leaking past the establishing line. It is where the ice rack starts and beneath the underside of the ice sheets. It is greasing up their development toward the ocean. The new discoveries show that barometrical warming is assaulting ice racks from above too.

Earth’s normal surface temperature has gone up by one degree Celsius since the nineteenth century. It is enough to expand the power of dry seasons, heat waves and tropical typhoons. However, the air over Antarctica has warmed more than twice that much. One of the outcomes has been the presence of long precipices corresponding to the shore line – up to many meters down – on the head of ice racks. As surface ice dissolves, water fills these gaps and improves the probability of a cycle called hydrofracturing.

At the point when this occurs, water – which is heavier than ice – “brutally powers the cracks to zip open and cause the rack to quickly break down”, the specialists said in an announcement. The Antarctic Peninsula, which has warmed more than some other piece of the landmass, has appeared in sensational design what this can prompt.

Significant lumps of the Antarctica Peninsula’s Larsen Ice Shelf – which had been steady for over 10,000 years – crumbled inside days in 1995, and again in 2002. This was trailed by the separation of the close by Wilkins Ice Shelf in 2008 and 2009.

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Salty lake, ponds may be gurgling beneath South Pole on Mars – iNFOnews

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This Aug. 26, 2003 image made available by NASA shows Mars photographed by the Hubble Space Telescope on the planet’s closest approach to Earth in 60,000 years. A network of salty ponds may be gurgling beneath Mars’ South Pole alongside a large underground lake, raising the prospect of tiny, swimming Martian life. Italian scientists reported their findings Monday, Sept. 28, 2020 two years after identifying what they believed to be a large subglacial lake.
Image Credit: AP, NASA

September 29, 2020 – 5:30 AM

CAPE CANAVERAL, Fla. – A network of salty ponds may be gurgling beneath Mars’ South Pole alongside a large underground lake, raising the prospect of tiny, swimming Martian life.

Italian scientists reported their findings Monday, two years after identifying what they believed to be a large buried lake. They widened their coverage area by a couple hundred miles, using even more data from a radar sounder on the European Space Agency’s Mars Express orbiter.

In the latest study appearing in the journal Nature Astronomy, the scientists provide further evidence of this salty underground lake, estimated to be 12 miles to 18 miles (20 kilometres to 30 kilometres) across and buried 1 mile (1.5 kilometres) beneath the icy surface.

Even more tantalizing, they’ve also identified three smaller bodies of water surrounding the lake. These ponds appear to be of various sizes and are separate from the main lake.

Roughly 4 billion years ago, Mars was warm and wet, like Earth. But the red planet eventually morphed into the barren, dry world it remains today.

The research team led by Roma Tre University’s Sebastian Emanuel Lauro used a method similar to what’s been used on Earth to detect buried lakes in the Antarctic and Canadian Arctic. They based their findings on more than 100 radar observations by Mars Express from 2010 to 2019; the spacecraft was launched in 2003.

All this potential water raises the possibility of microbial life on — or inside — Mars. High concentrations of salt are likely keeping the water from freezing at this frigid location, the scientists noted. The surface temperature at the South Pole is an estimated minus 172 degrees Fahrenheit (minus 113 degrees Celsius), and gets gradually warmer with depth.

These bodies of water are potentially interesting biologically and “future missions to Mars should target this region,” the researchers wrote.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

News from © The Associated Press, 2020

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Buried lakes of liquid water discovered on Mars – BBC News

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Three underground lakes have been detected near the south pole of Mars.

Scientists also confirmed the existence of a fourth lake – the presence of which was hinted at in 2018.

Liquid water is vital for biology, so the finding will be of interest to researchers studying the potential for life elsewhere in the Solar System.

But the lakes are also thought to be extremely salty, which could make it difficult for any microbial life to survive in them.

Mars’ thin atmosphere means that the presence of liquid water on the surface is a near-impossibility. But water could remain liquid below ground.

The latest discovery was made using data from a radar instrument on the European Space Agency’s (Esa) Mars Express spacecraft, which has been orbiting the Red Planet since December 2003.

In 2018, researchers used data from the Marsis radar to report signs of a 20km-wide subsurface lake located 1.5km under Mars’ south polar layered deposits, a thick polar cap formed by layers of ice and dust.

However, that finding was based on 29 observations collected by Marsis between 2012 and 2015. Now, a team including many of the same scientists from the 2018 study have analysed a much bigger dataset of 134 radar profiles gathered between 2010 and 2019.

“Not only did we confirm the position, extent and strength of the reflector from our 2018 study, but we found three new bright areas,” said co-author Elena Pettinelli from Roma Tre University in Italy.

“The main lake is surrounded by smaller bodies of liquid water, but because of the technical characteristics of the radar, and of its distance from the Martian surface, we cannot conclusively determine whether they are interconnected.”

The team borrowed a technique commonly used in radar sounder investigations of sub-glacial lakes in Antarctica, Canada and Greenland, adapting the method to analyse the data from Marsis.

“The interpretation that best reconciles all the available evidence is that the high intensity reflections (from Mars) are coming from extended pools of liquid water,” said co-author Sebastian Lauro, also from Roma Tre University.

There’s not enough heat at these depths to melt the ice, so scientists believe the liquid water must contain high concentrations of dissolved salts. These chemical salts (different to the stuff we sprinkle on our chips) can significantly lower water’s freezing point.

In fact, recent experiments have shown that water with dissolved salts of magnesium and calcium perchlorate (a chemical compound containing chlorine bound to four oxygens) can remain liquid at temperatures of -123C.

“These experiments have demonstrated that brines can persist for geologically significant periods of time even at the temperatures typical of the Martian polar regions (considerably below the freezing temperature of pure water),” said co-author Graziella Caprarelli, from the University of Southern Queensland, Australia.

“Therefore we think that any process of formation and persistence of sub-ice water beneath the ice polar caps requires the liquid to have high salinity.”

Whether life could survive in such conditions depends on just how salty these Martian pools are. On Earth, only very specific types of microbes, known as halophiles, can survive in the saltiest bodies of water.

Roberto Orosei, chief scientist on the Marsis experiment, said: “While the existence of a single sub-glacial lake could be attributed to exceptional conditions such as the presence of a volcano under the ice sheet, the discovery of an entire system of lakes implies that their formation process is relatively simple and common, and that these lakes have probably existed for much of Mars’ history.

“For this reason, they could still retain traces of any life forms that could have evolved when Mars had a dense atmosphere, a milder climate and the presence of liquid water on the surface, similar to the early Earth.”

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INRS Researchers Develop a New Membraneless Fuel Cell – Canada NewsWire

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Conventional fuel cells are ubiquitous. They power electric cars on today’s roads and were part of the computers used in the 1969 Apollo moon landing. These fuel cells lose voltage as they are used and eventually stop working. This happens because alcohol molecules (methanol or ethanol) in the fuel cell’s anode compartment crossover the membrane separating them from the cathode compartment. Oxygen molecules in the cathode compartment react with the alcohol, causing a drop in voltage.

Numerous scientists have unsuccessfully tried to develop a membrane that stops alcohol molecules from passing through it. Professor Mohamed Mohamedi, a lead author of the study published on September 8, took another tack: developing a fuel cell without a membrane. 

His novel solution costs less and requires fewer steps to manufacture, but it fails to address a key challenge. “When the membrane is removed, the methanol or ethanol reacts with the oxygen, just like in conventional fuel cells. To prevent voltage drops, we had to develop selective electrodes in the cathode compartment. These electrodes, designed by doctoral student Juan Carlos Abrego-Martinez, remain inactive in the presence of alcohol molecules but are sensitive to the oxygen that generates electricity,” Professor Mohamedi explains. He notes another unique property of this membraneless fuel cell: it uses oxygen from the air around it.

From Model to Prototype

The first step the researchers took in building a working prototype was to run numerical simulations created by Alonso Moreno Zuria, INRS postdoctoral fellow and a lead author of the study. Through computer modelling, the team tested different configurations of selective electrodes in the fuel cell. “Conventional fuel cells are like sandwiches, with the membrane in the middle. We chose instead to work on a single-layer design. We had to determine how to arrange and space the electrodes to maximize fuel use while keeping ambient air oxygen concentration in mind,” says Professor Mohamedi.

Once the researchers settled on a configuration, they tested a prototype that became a proof of concept. The membraneless fuel cell powered an LED for four hours using only 234 microlitres of methanol. The researchers want to optimize the fuel cell so it can use ethanol, a greener fuel that can be produced from biomass and agricultural waste. Ethanol also provides more power per equivalent unit of volume.

The team expects the fuel cell to power portable electronics such as mobile phones and microsystems such as air pollution sensors. Unlike conventional batteries that store electricity and must be recharged, fuel cells continue to produce energy as long as fuel is available. “This energy supply method is particularly effective when recharging is not possible. Imagine being in the middle of the desert, without electricity. You could recharge your mobile phone using a small capsule of ethanol that you connect to the device,” says Professor Mohamedi.

This pioneering technology has already attracted industry attention even though the research team is only at the prototype stage. 

About the study
The researchers received financial support from the Natural Sciences and Engineering Research Council (NSERC), the Quebec Centre for Advanced Materials (QCAM), the UNESCO/MATECSS chair, Consejo Nacional de Ciencia y Tecnología (CONACYT, Mexico), and Científicos Mexicanos en el Extranjero.
https://doi.org/10.1016/j.rser.2020.110045

About INRS

INRS is a university dedicated exclusively to graduate level research and training. Since its creation in 1969, INRS has played an active role in Quebec’s economic, social, and cultural development and is ranked first for research intensity in Quebec and second in Canada. INRS is made up of four interdisciplinary research and training centres in Quebec City, Montreal, Laval, and Varennes, with expertise in strategic sectors: Eau Terre Environnement, Énergie Matériaux Télécommunications, Urbanisation Culture Société, and Armand-Frappier Santé Biotechnologie. The INRS community includes more than 1,400 students, postdoctoral fellows, faculty members, and staff.

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SOURCE Institut National de la recherche scientifique (INRS)

For further information: Audrey-Maude Vézina, Service des communications de l’INRS, 418 254-2156, [email protected]

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