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Himalayan Glacier Research Has Global Impact

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Though Ganai does not have enough scientificexperience to trek to the accumulation zone, he and six other members of the team play a vital role collecting data on the lower portions of the glacier know as the ablation zone, or the area where the ice melts.

Ganai and colleagues first drill a series of holes into the ice of the ablation zone and then take pre-measured sticks (literally bamboo poles) and place them in the holes. After each melting season, the team will measure the length of the pole exposed, take notes, and repeat the procedure. This tells them how much the volume of the glacier has changed between melting seasons.

The process may sound elementary, but it's extremely tedious and labor-intensive. Much of the cutting and drilling takes place at heights of 13,000 feet (3,962 meters) on icy crevasses, where a mishap could mean severe injury or even death. While taking measurements on the accumulation zone on this expedition, Tayal slipped through a crevasse and fractured his tailbone.

Despite the risk, Tayal believes the research done on Kolahoi will have a global impact.

"We do not have much reliable data on western Himalayan glaciers," he said.

"If you want to know what the global impact of climate change is going to be and make accurate projections, you can not exclude the Himalaya from the Rockies and the Alps."

"No Good Anymore"

To measure the flow of meltwater through the Liddar Valley, TERI established a monitoring station. Genai helped build the structure in the West Liddar River, the main tributary of the Jhelum River, which is one of the largest rivers in Kashmir.

Each day the station is collecting data on a looming disaster, Tayal said.

(Related: "Melting Himalayan Glaciers May Doom Towns.")

As the glaciers in the western Himalaya disappear, seasonal run off coming into Pakistan from Kashmir could drop by 40 percent, according to the Washington, D.C.-based research institute the Woodrow Wilson Center.

This will no doubt have a devastating effect on the millions who depend on the run off, experts say.

And some people downstream from Kolahoi are already suffering. Thebakarwals, or nomadic herders, who bring hundreds of thousands of sheep to graze in the Liddar Valley have dealt with unpredictable water fluxes in recent years.

"We used to know when the waters would be in the river," said a middle-aged bakarwal woman, as she smacked a few of her sheep that had scattered from the herd.

"But now the waters are too high or too low. I want my children to get an education," the mother of three said. "This way of life is no good anymore."

Ganai is also worried. "We are dependent on the beauty of Kashmir," he said, looking at the mountain skyline.

"If Kolahoi goes, I don't know what we will do."

Rebecca Byerly reported from Kashmir with funding from the Pulitzer Center for Crisis Reporting.

Текст 2

NASA's Curiosity Rover Finds Clues to How Water Helped Shape Martian Landscape

Observations by NASA's Curiosity Rover indicate Mars' Mount Sharp was built by sediments deposited in a large lake bed over tens of millions of years.

This interpretation of Curiosity's finds in Gale Crater suggests ancient Mars maintained a climate that could have produced long-lasting lakes at many locations on the Red Planet.

"If our hypothesis for Mount Sharp holds up, it challenges the notion that warm and wet conditions were transient, local, or only underground on Mars," said Ashwin Vasavada, Curiosity deputy project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. "A more radical explanation is that Mars' ancient, thicker atmosphere raised temperatures above freezing globally, but so far we don't know how the atmosphere did that."

Why this layered mountain sits in a crater has been a challenging question for researchers. Mount Sharp stands about 3 miles (5 kilometers) tall, its lower flanks exposing hundreds of rock layers. The rock layers - alternating between lake, river and wind deposits -- bear witness to the repeated filling and evaporation of a Martian lake much larger and longer-lasting than any previously examined close-up.

"We are making headway in solving the mystery of Mount Sharp," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology in Pasadena. "Where there's now a mountain, there may have once been a series of lakes."

Curiosity currently is investigating the lowest sedimentary layers of Mount Sharp, a section of rock 500 feet (150 meters) high, dubbed the Murray formation. Rivers carried sand and silt to the lake, depositing the sediments at the mouth of the river to form deltas similar to those found at river mouths on Earth. This cycle occurred over and over again.

"The great thing about a lake that occurs repeatedly, over and over, is that each time it comes back it is another experiment to tell you how the environment works," Grotzinger said. "As Curiosity climbs higher on Mount Sharp, we will have a series of experiments to show patterns in how the atmosphere and the water and the sediments interact. We may see how the chemistry changed in the lakes over time. This is a hypothesis supported by what we have observed so far, providing a framework for testing in the coming year."

After the crater filled to a height of at least a few hundred yards, or meters, and the sediments hardened into rock, the accumulated layers of sediment were sculpted over time into a mountainous shape by wind erosion that carved away the material between the crater perimeter and what is now the edge of the mountain.

On the 5-mile (8-kilometer) journey from Curiosity's 2012 landing site to its current work site at the base of Mount Sharp, the rover uncovered clues about the changing shape of the crater floor during the era of lakes.

"We found sedimentary rocks suggestive of small, ancient deltas stacked on top of one another," said Curiosity science team member Sanjeev Gupta of Imperial College in London. "Curiosity crossed a boundary from an environment dominated by rivers to an environment dominated by lakes."

Despite earlier evidence from several Mars missions that pointed to wet environments on ancient Mars, modeling of the ancient climate has yet to identify the conditions that could have produced long periods warm enough for stable water on the surface.

NASA's Mars Science Laboratory Project uses Curiosity to assess ancient, potentially habitable environments and the significant changes the Martian environment has experienced over millions of years. This project is one element of NASA's ongoing Mars research and preparation for a human mission to the planet in the 2030s.

"Knowledge we're gaining about Mars' environmental evolution by deciphering how Mount Sharp formed will also help guide plans for future missions to seek signs of Martian life," said Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington.

JPL, managed by Caltech, built the rover and manages the project for NASA's Science Mission Directorate in Washington.

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