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Topic: Erosion

NASA’s New Horizons mission examines Pluto’s jagged ridges of Methane Ice

 

Written by Frank Tavares
NASA’s Ames Research Center

NASA - National Aeronautics and Space AdministrationMountain View, CA – NASA’s New Horizons mission revolutionized our knowledge of Pluto when it flew past that distant world in July 2015. Among its many discoveries were images of strange formations resembling giant knife blades of ice, whose origin had remained a mystery.

Now, scientists have turned up a fascinating explanation for this “bladed terrain”: the structures are made almost entirely of methane ice, and likely formed as a specific kind of erosion wore away their surfaces, leaving dramatic crests and sharp divides.

Pluto’s bladed terrain as seen from New Horizons during its July 2015 flyby. (NASA/JHUAPL/SwRI)

Pluto’s bladed terrain as seen from New Horizons during its July 2015 flyby. (NASA/JHUAPL/SwRI)

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NASA Survey discovers extensive coastal erosion from Gulf Oil Spill

 

Written by Alan Buis
NASA’s Jet Propulsion Laboratory

NASA - National Aeronautics and Space AdministrationPasadena, CA – Dramatic, widespread shoreline loss is revealed in new NASA/U.S. Geological Survey annual maps of the Louisiana marshlands where the coastline was most heavily coated with oil during the 2010 BP Deepwater Horizon oil spill in the Gulf of Mexico.

Following the spill, the length of shoreline that receded more than 13 feet (4 meters) a year quadrupled compared to the year before the spill. The land losses occurred mainly in areas where oil had washed ashore during the spill.

2010 photo of a shoreline in Bay Jimmy, Plaquemines Parish, Louisiana, impacted by the BP Deepwater Horizon oil spill. Oil weakens and kills vegetation, leading to the loss of roots that help hold soil together. (Bruce A. Davis, Department of Homeland Security)

2010 photo of a shoreline in Bay Jimmy, Plaquemines Parish, Louisiana, impacted by the BP Deepwater Horizon oil spill. Oil weakens and kills vegetation, leading to the loss of roots that help hold soil together. (Bruce A. Davis, Department of Homeland Security)

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NASA Study finds Sea Level changes may be due to Climate Cycles

 

Written by Alan Buis
NASA’s Jet Propulsion Laboratory

NASA - National Aeronautics and Space AdministrationPasadena, CA – The tropical Pacific Ocean isn’t flat like a pond. Instead, it regularly has a high side and a low side. Natural cycles such as El Niño and La Niña events cause this sea level seesaw to tip back and forth, with the ocean near Asia on one end and the ocean near the Americas on the other.

But over the last 30 years, the seesaw’s wobbles have been more extreme, causing variations in sea levels up to three times higher than those observed in the previous 30 years. Why might this be?

Higher Pacific sea levels increase coastal flooding risks. (Flickr user Alan Grinberg, "Coming Ashore!", CC BY-NC-ND 2.0)

Higher Pacific sea levels increase coastal flooding risks. (Flickr user Alan Grinberg, “Coming Ashore!”, CC BY-NC-ND 2.0)

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NASA reports Jason-3 satellite set to launch in July

 

Written by Alan Buis
NASA’s Jet Propulsion Laboratory

NASA - National Aeronautics and Space AdministrationPasadena, CA – You can’t predict the outcome of a marathon from the runners’ times in the first few miles. You’ve got to see the whole race. Global climate change is like that: You can’t understand it if all you have is a few years of data from a few locations. That’s one reason that a fourth-generation satellite launching this summer is something to get excited about.

Jason-3, a mission led by the National Oceanic and Atmospheric Administration that is currently scheduled to launch on July 22nd, is the latest in a series of U.S.-European satellite missions that have been measuring the height of the ocean surface for 23 years.

Artist's rendering of Jason-3. (NASA/JPL-Caltech)

Artist’s rendering of Jason-3. (NASA/JPL-Caltech)

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Section of Clarksville Greenway to Close for Repairs

 

Clarksville GreenwayClarksville, TN – A section of the Clarksville Greenway will be closed to the public September 20t-21st, 2012 and September 24th-25th, 2012, for erosion control mediation.

The partial closure will begin at the top of the large hill before the small pedestrian bridge about a mile and a half down on the trail located to the right of the Pollard Road trail head. The beginning of the trail along with the trail to the left of the Pollard Road trail head will continue to remain open to the public. «Read the rest of this article»

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News from the Dunbar Cave State Natural Area

 

Dunbar Cave seen from across Swan LakeWe are in a slow period for flowers blooming. The spring flowers are long gone, the end of summer and fall flowers are not up yet. Right now you can see Wild Petunia, Queen Anne’s Lace (not native), Butterfly Weed (an orange milkweed, which unfortunately visitors keep breaking off, so you may or may not be able to see the flowers), clovers, Lopseed, Virginia Knotweed, Wild Potato Vine, Naked-stem Tick Trefoil, Downy False Foxglove, Pencil Flower, and my favorite right now, the Yellow Passion Flower, which is a relative of the much more showy purple, white and yellow state wildflower of Tennessee.

new trail 007

Yellow Passion Flower

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