Thursday, December 26, 2013

Earth Observatory Photos

I hope that everyone had a safe and joyous Christmas.  For today's blog posting, I decided to see what NASA has posted lately on their Earth Observatory web page at http://earthobservatory.nasa.gov/.

In 1968 the Apollo 8 mission took this incredible image of the Earth rising from the moon.


Now for more recent photos, mostly taken from the International Space Station.  Demure, Turkey is shown below.


The photo below shows the dormant volcano is Sollipulli, located in central Chile near the border with Argentina. The volcano sits in the southern Andes Mountains within Chile’s Parque Nacional Villarica. This photograph by an astronaut on the International Space Station features the summit (2,282 meters, or 7,487 feet, above sea level) and the bare slopes above the tree line. Lower elevations are covered with green forests indicative of Southern Hemisphere summer.  The summit of Sollipulli is occupied by a four-kilometer wide caldera, currently filled with a snow-covered glacier. While most calderas form after violent, explosive eruptions, the types of rock and other deposits associated with such events have not been found at Sollipulli. Geologic evidence does indicate explosive activity occurred about 2,900 years ago, and lava flows were produced approximately 700 years ago. Together with the craters and scoria cones along the outer flanks of the caldera, this history suggests Sollipulli could erupt violently again, presenting a potential hazard to towns such as Melipeuco and the wider region.


The following photos show the results of recent volcanic activity along the western edge of the Pacific “Ring of Fire," which gave rise to a tiny island in late November 2013. Located in the Ogasawara Islands, part of the Volcano Islands arc, the new islet sits about 1,000 kilometers (600 miles) south of Tokyo in waters considered part of Japanese territory.

The water around the island is discolored by volcanic minerals and gases and by seafloor sediment stirred up by the ongoing volcanic eruption. The faint white puffs above the center and southwest portion of the island are likely steam and other volcanic gases associated with the eruption.
The new island (or “Niijima” in Japanese), rose up out of the sea during a volcanic eruption first reported on November 20, 2013. The new island sits about 500 meters from Nishino-shima, another volcanic island that last erupted and expanded in 1973–74. The two islands are located at approximately 27°14’ North latitude and 140°52’ East longitude, about 130 kilometers (80 miles) from the nearest inhabited island.

In the first few days after the eruption, scientists speculated that the new island might not last.
But according to news reports, the new island is still erupting and growing. Scientists from the Japan Meteorological Agency think the island is large enough to survive for at least several years, if not permanently. By early December, it had grown to 56,000 square meters (13.8 acres), about three times its initial size. It stands 20 to 25 meters above the sea level.


Below are two aerial photographs taken by the Japan Coast Guard (JCG) on December 1 (top) and December 13, 2013.





The picture below shows morning sunlight illuminating the southeast-facing slopes of the Islands of the Four Mountains in this photograph taken from the International Space Station (ISS). The islands, part of the Aleutian Island chain, are actually the upper slopes of volcanoes rising from the sea floor: Carlisle, Cleveland, Herbert, and Tana. Carlisle and Herbert volcanoes are distinct cones and form separate islands. Cleveland volcano and the Tana volcanic complex form the eastern and western ends respectively of Chuginadak Island. A cloud bank obscures the connecting land mass in this image.

Cleveland volcano (elevation 1,730 meters above sea level) is one of the most active in the Aleutian chain, with its most recent activity—eruptions and lava flow emplacement—taking place in May of 2013 (A crew aboard the ISS captured an earlier eruption in 2006.) The northernmost of the islands, Carlisle volcano (peak elevation 1,620 meters), had its last confirmed eruption occurred in 1828, with unconfirmed reports of activity in 1987. Herbert volcano (peak elevation 1280 meters) displays a classic cone structure breached by a two-kilometer wide summit caldera (image lower left), but there are no historical records of volcanic activity. The easternmost peak, Tana (1,170 meters) is a volcanic complex comprised of two east-west trending volcanoes and associated younger cinder cones. Like Herbert volcano, there is no historical record of activity at Tana.

A layer of low cloud and/or fog obscures much of the lower elevations of the islands and the sea surface, but the clouds also indicate the general airflow pattern around and through the islands. Directly to the south-southeast of Cleveland volcano, a Von Karman vortex street is visible. Shadows cast by the morning sun extend from the peaks towards the northwest. The peaks of all of the Four Islands have snow cover. This is distinct from the clouds due to both higher brightness (white versus gray) and the specific location on the landscape.


The photo below documents a rare winter storm dropped snow across much of the Middle East between December 10 and 13, 2013. For the most part, the snow is confined to higher elevations in Syria, Egypt, Lebanon, Israel and the West Bank, and Jordan. Some lower-elevation desert regions in Syria are also snowy.  Snow storms in the Middle East are not frequent but not uncommon either. However, this one was unusually early in the winter and more intense than normal. The storm paralyzed Jerusalem with 30 to 50 centimeters (12 to 20 inches) of snow, knocking out power for roughly 15,000 households. The snow closed mountain roads leading into the city, effectively cutting Jerusalem off. Amman, Jordan, received about 45 cm (18 inches) of snow, and Lebanon and Syria also were unusually cold and snowy.




However you measure them, the world’s tallest mountains are treacherous. They have towering blocks of ice—seracs—that can crush climbers in seconds. They are prone to tremendous avalanches of rock and snow that obliterate entire expeditions. And they are home to spider webs of ice crevasses that swallow humans whole. Even during the summer, average daytime temperatures are frigid. And, hurricane-force winds are common.

Then, of course, there is the lack of oxygen. At 5,000 meters (16,404 feet), the atmosphere contains about half as much oxygen as at sea level. By 6,000 meters (19,685 feet), the air is so thin that full acclimatization is no longer possible. No matter how fit, climbers begin to slowly suffocate. By 7,000 meters (22,966 feet), survival times plummet and lucid thought becomes difficult. By 8,000 meters—the so-called “death zone”—even the strongest climbers can survive for a few days at best.
The three most dangerous of the eight-thousanders—Annapurna, K2, and Nanga Parbat—claim the life of about one climber for every four who reach the top. The fatality rate for Annapurna, the most dangerous mountain in the world, is over 30 percent. Bottled oxygen and guided climbs have made Mount Everest much safer than it was decades ago, but the world’s tallest mountain still takes lives regularly. Nine people died on the mountain in 2013. Ten in 2012.

All this risk is for what, exactly? Reinhold Messner, the first person to climb all fourteen of the eight-thousanders, pointed to something he calls “overview” to explain the allure. “It is not the mountain but the view from the peak that suggests increased awareness,” he writes in the book Mountains from Space. “The person who stands on top of one comes back down with a new sense of the world.”
Messner risked everything for fleeting views from the top of the world, ascending many of the eight-thousanders solo and without the aid of bottled oxygen. It took him 16 years (1970–1986) to climb them all. Only 31 other people—give or take a few because the records of some climbers are considered controversial—have done it since.

While the summit of an eight-thousander may represent the ultimate view on Earth, satellites take Messner’s concept of overview to a whole new level. The summit of Mount Everest is about 8.8 kilometers (5.5 miles) above sea level. Most polar-orbiting satellites fly at an altitude of 705 kilometers (438 miles). So when viewed from space, the world’s tallest mountains become blotches of shadow, rock, and snow. Epic glaciers become narrow tongues of ice feeding glacial lakes that look like puddles. Deadly storms become mere tufts of cloud.


Ground photography of Mount Everest and the other tall peaks are ubiquitous, but the gallery that follows—a collection of imagery acquired by the Advanced Land Imager (ALI) on NASA’s EO-1 satellite—offers a less familiar perspective. The sensors on ALI looked directly down on the mountains, not from an oblique angle like a passenger on an airplane or an astronaut on the International Space




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