12. March 2013

Where has all the ice gone?

From Tree Hugger By Emily E. Adams On March 8, 2013

As the earth warms, glaciers and ice sheets are melting and seas are rising. Over the last century, the global average sea level rose by 17 centimeters (7 inches). This century, as waters warm and ice continues to melt, seas are projected to rise nearly 2 meters (6 feet), inundating coastal cities worldwide, such as New York, London, and Cairo. Melting sea ice, ice sheets, and mountain glaciers are a clear sign of our changing climate.

In September 2012, sea ice in the Arctic Ocean shrank to a record low extent and volume. The region has warmed 2 degrees Celsius (3.6 degrees Fahrenheit) since the 1960s—twice as much as lower latitudes. With less snow and ice to reflect the sun’s rays and with more exposed ocean to absorb heat, a vicious cycle leads to even warmer temperatures. Thinner ice combined with rising temperatures makes it increasingly difficult for the sea ice to recover. The historically ever-present white cap at the top of the globe could disappear entirely during the summer within two decades.

The Arctic plays a pivotal role in large-scale weather patterns. The stark contrast between cold air at the North Pole and warmer air in the temperate zone drives the jet stream over North America, Europe, and Russia. As the Arctic continues to warm faster than the rest of the globe, this contrast diminishes. This can change the path of the jet stream and slow it down, leaving weather systems in the same place for a longer time. A rainy spell that sticks around can turn into flooding, while a sunny spell can turn into a drought.

Warming in the Arctic is particularly important because of its effects on Greenland’s enormous ice sheet. Greenland’s ice loss has accelerated from 51 billion tons per year in the 1990s to 263 billion tons per year today. In July 2012, an iceberg twice the size of the island of Manhattan calved off Petermann glacier in northwestern Greenland. This was the second large calving event off this glacier in just two years: the iceberg that broke away in August 2010 was twice as large.

While Greenland’s ice loss is astonishing, on the other side of the globe, parts of Antarctica’s vast ice sheet may be even less stable. The continent is flanked by 54 major ice shelves, which act as brakes slowing the movement of ice in land-based glaciers out to sea. Twenty of them show signs of thinning and weakening, which translates into accelerated ice loss. After the 3,250-square-kilometer Larsen B Ice Shelf collapsed in 2002, for instance, the glaciers it was bracing flowed up to eight times faster than before. The most dramatic thinning is in West Antarctica.

Pine Island glacier, which flows into the Amundsen Sea, is one of the main outlets for West Antarctic ice. A rift now stretches 29 kilometers across the glacier’s ice shelf, threatening to release an iceberg 14 times the size of Manhattan. Warm deep ocean water has penetrated beneath it, causing an astounding rate of retreat. In the past 20 years, the grounding line where the bottom of the glacier meets the ocean retreated by 25 kilometers, whereas over the previous 10,000 years it only moved back by 90 kilometers.

The movement of land-based ice to the ocean raises sea level. Together the West Antarctic and Greenland ice sheets contain enough ice to raise seas by 12 meters, if they disintegrate entirely. Just a one-meter rise—well within the projections for this century—would flood half of the riceland in Bangladesh and much of the Mekong Delta in Viet Nam, two countries that are leading rice producers.

Melting mountain glaciers contribute to sea level rise as well, but they are of more immediate concern because of their roles in the everyday lives of millions of people. They provide drinking water for villages and cities, irrigation water for farms, and fuel for hydropower plants. These vital services are in jeopardy because mountain glaciers worldwide are shrinking at accelerating rates. For instance, 37 reference glaciers studied by the World Glacier Monitoring Service shrank three times faster from 2000 to 2009 than from 1980 to 1989. (See data.)

The glaciers in the Himalayas—the largest concentration of ice outside of the two poles—have been dubbed Asia’s “water towers” because of their large water storage capacity. Their runoff feeds Asia’s great rivers, including the Indus, Ganges, and Brahmaputra, which support hundreds of millions of people. Climbers attracted to the one-of-a-kind peaks tell their own stories of melting ice. In many places, what had been blinding white ice and snow fields in the days of the first explorers are now bare rock. More avalanches and more crevasses add risk to already dangerous treks. Data collected by the Chinese Academy of Sciences validate these anecdotes, showing that glacier melt in the Eastern and Central Himalayas has sped up. This will continue as temperatures rise.

Glaciers in the Alps perform a similar water tower function for Europe, and they too are shrinking. Switzerland’s Great Aletsch glacier, the largest in the Alps, has retreated by more than 2 kilometers since 1900. In Germany, a local ski company concerned by the rapid shrinkage of Zugspitze glacier resorted to covering the ice with a 9,000-square-meter reflective blanket. But this is just a Band-Aid; without addressing the real problem of rising temperature, 90 percent of all Alpine glaciers could be wiped out by 2100. Such a dramatic loss can already be seen in the nearby Spanish Pyrenees Mountains, where close to 90 percent of the glacier cover has disappeared over the past century.

In the United States, almost all of Alaska’s glaciers are retreating or thinning. For example, data collected at Gulkana glacier each year since 1966 reveal an ice loss trend that has sped up since the early 1990s. In Montana, Glacier National Park may be “glacier” in name only within two decades. Only 25 of the park's 150 original glaciers remain.

Nearly all of the world’s tropical glaciers are found in South America in the Andes. Rising temperatures have more than tripled the rate of ice loss from these glaciers since the mid-1970s. In Peru, more than 2 million people depend on runoff from the Cordillera Blanca (the White Range). As the mountain range’s glaciers began to waste away, water runoff temporarily increased. But glaciologist Michel Baraer of McGill University in Canada estimates that runoff has already peaked and is now in decline. Bolivia’s famous Chacaltaya glacier, once a popular ski site, can now be found only on old maps. The runoff from Zongo glacier flows through 10 hydropower plants that currently generate some 25 percent of Bolivia’s electricity. But Zongo’s ice is retreating by 9 meters per year. As water supplies dwindle, competition among hydropower stations, farmers, and cities will get worse.

The last remaining glaciers in the tropical Pacific, on Indonesia’s Puncak Jaya Mountain, also are melting fast. Between 1936 and 2006, this mountain lost close to 80 percent of its ice cover. During world-renowned glaciologist Lonnie Thompson’s recent expedition to sample the ice before it disappears—along with the historical climate data trapped inside the ice—heavy rains thinned the ice around his campsite by 30 centimeters in just 13 days.

Tropical glaciers in Africa are wasting away too. Less than 10 percent of the original ice cover remains atop Mount Kenya. In 2009, Nairobi had rolling blackouts due to the diminished runoff from the mountain flowing to hydropower stations. The problems are more than just practical; the glacier has long held cultural and spiritual significance. Neighboring Uganda’s Rwenzori Mountains could be ice-free within 20 years.

The race is on between disappearing ice, which is melting faster than predicted, and reductions in carbon emissions, which is happening slower than hoped. The world will need a World War II–type mobilization to shift from climate-disrupting fossil fuels to renewable sources of energy if we are to stand a chance of preventing runaway global warming and unstoppable melting.

# # #

For a plan to stabilize the Earth’s climate, see “Time for Plan B."

Tags: Roger, 13Mar, Ecodestruction

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Fri

Nov

2015

Are Languages Products of their Environment?

shutterstock_222422665_151112

DISCOVER MAGAZINE published this very interesting article:

Languages Are Products of Their Environments

The characteristics that make each language unique may actually be adaptations to the acoustics of different environments.

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Thu

Jun

2014

Fun with Newspaper Headlines

Newspaper Headlinigs

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Tue

Jun

2014

The Case for Reparations

The Case for Reparations

Two hundred fifty years of slavery. Ninety years of Jim Crow. Sixty years of separate but equal. Thirty-five years of racist housing policy. Until we reckon with our compounding moral debts, America will never be whole.

By Ta-Nehisi Coates

May 21, 2014

Chapters

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Mon

Jun

2014

A Look At 19th Century Children In The USA

PHILADELPHIA — DINNER with your children in 19th-century America often required some self-control. Berry stains in your daughter’s hair? Good for her. Raccoon bites running up your boy’s arms? Bet he had an interesting day.

As this year’s summer vacation begins, many parents contemplate how to rein in their kids. But there was a time when Americans pushed in the opposite direction, preserved in Mark Twain’s cat-swinging scamps. Parents back then encouraged kids to get some wildness out of their system, to express the republic’s revolutionary values.

The New York Times

Sunday Review

By JON GRINSPAN MAY 31, 2014

A late 19th century family taking a stroll down a set of railroad tracks

American children of the 19th century had a reputation. Returning British visitors reported on American kids who showed no respect, who swore and fought, who appeared — at age 10 — “calling for liquor at the bar, or puffing a cigar in the streets,” as one wrote. There were really no children in 19th-century America, travelers often claimed, only “small stuck-up caricatures of men and women.”

This was not a “carefree” nation, too rough-hewed to teach proper manners; adults deliberately chose to express new values by raising “go-ahead” boys and girls. The result mixed democracy and mob rule, assertiveness and cruelty, sudden freedom and strict boundaries. Visitors noted how American fathers would brag that their disobedient children were actually “young republicans,” liberated from old hierarchies. Children were still expected to be deferential to elders, but many were trained to embody their nation’s revolutionary virtues. “The theory of the equality” was present at the ballot box, according to one sympathetic Englishman, but “rampant in the nursery.”

Boys, in particular, spent their childhoods in a rowdy outdoor subculture. After age 5 or so they needed little attention from their mothers, but were not big enough to help their fathers work. So until age 10 or 12 they spent much of their time playing or fighting.

The writer William Dean Howells recalled his ordinary, violent Ohio childhood, immersed in his loose gang of pals, rarely catching a “glimpse of life much higher than the middle of a man.” Howells’s peers were “always stoning something,” whether friends, rivals or stray dogs. They left a trail of maimed animals behind them, often hurt in sloppy attempts to domesticate wild pets.

And though we envision innocents playing with a hoop and a stick, many preferred “mumbletypeg” — a game where two players competed to see who could throw a knife closer to his own foot. Stabbing yourself meant a win by default.

Left to their own devices, boys learned an assertive style that shaped their futures. The story of every 19th-century empire builder — Carnegie, Rockefeller, Vanderbilt — seems to begin with a striving 10-year-old. “Boy culture” offered training for the challenges of American manhood and a reprieve before a life of labor.

But these unsupervised boys also formed gangs that harassed the mentally ill, the handicapped and racial and ethnic minorities. Boys played an outsize role in the anti-Irish pogroms in 1840s Philadelphia, the brutal New York City draft riots targeting African-Americans during the Civil War and attacks on Chinese laborers in Gilded Age California. These children did not invent the bigotry rampant in white America, but their unrestrained upbringing let them enact what their parents mostly muttered.

Their sisters followed a different path. Girls were usually assigned more of their mothers’ tasks. An 8-year-old girl would be expected to help with the wash or other physically demanding tasks, while her brother might simply be too small, too slow or too annoying to drive the plow with his father. But despite their drudgery, 19th-century American girls still found time for tree climbing, bonfire building and waterfall-jumping antics. There were few pretty pink princesses in 19th-century America: Girls were too rowdy and too republican for that.

So how did we get from “democratic sucklings” to helicopter parents? Though many point to a rise of parental worrying after the 1970s, this was an incremental change in a movement that began a hundred years earlier.

In the last quarter of the 19th century, middle-class parents launched a self-conscious project to protect children. Urban professionals began to focus on children’s vulnerabilities. Well-to-do worriers no longer needed to raise tough dairymaids or cunning newsboys; the changing economy demanded careful managers of businesses or households, and restrained company men, capable of navigating big institutions.

Demographics played a role as well: By 1900 American women had half as many children as they did in 1800, and those children were twice as likely to live through infancy as they were in 1850. Ironically, as their children faced fewer dangers, parents worried more about their protection.

Instead of seeing boys and girls as capable, clever, knockabout scamps, many reconceived children as vulnerable, weak and naïve. Reformers introduced child labor laws, divided kids by age in school and monitored their play. Jane Addams particularly worked to fit children into the new industrial order, condemning “this stupid experiment of organizing work and failing to organize play.”

There was good reason to tame the boys and girls of the 19th century, if only for stray cats’ sake. But somewhere between Jane Addams and Nancy Grace, Americans lost track of their larger goal. Earlier parents raised their kids to express values their society trumpeted.

“Precocious” 19th-century troublemakers asserted their parents’ democratic beliefs and fit into an economy that had little use for 8-year-olds but idealized striving, self-made men. Reformers designed their Boy Scouts to meet the demands of the 20th century, teaching organization and rebalancing the relationship between play and work. Both movements agreed, in their didactic ways, that playtime shaped future citizens.

Does the overprotected child articulate values we are proud of in 2014? Nothing is easier than judging other peoples’ parenting, but there is a side of contemporary American culture — fearful, litigious, controlling — that we do not brag about but that we reveal in our child rearing, and that runs contrary to our self-image as an open, optimistic nation. Maybe this is why sheltering parents come in for so much easy criticism: A visit to the playground exposes traits we would rather not recognize.

There is, however, a saving grace that parents will notice this summer. Kids are harder to guide and shape, as William Dean Howells put it, “than grown people are apt to think.” It is as true today as it was two centuries ago: “Everywhere and always the world of boys is outside of the laws that govern grown-up communities.” Somehow, they’ll manage to go their own way.

________________________________

A National Endowment for the Humanities fellow at the Massachusetts Historical Society who is writing a book on the role of young people in 19th-century American democracy.

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Mon

Apr

2014

Investigating Family's Wealth, China's Leader Signals a Change

From The New York Times

By CHRISTOPHER DREW and JAD MOUAWAD

APRIL 19, 2014

HONG KONG — His son landed contracts to sell equipment to state oil fields and thousands of filling stations across China. His son’s mother-in-law held stakes in pipelines and natural gas pumps from Sichuan Province in the west to the southern isle of Hainan. And his sister-in-law, working from one of Beijing’s most prestigious office buildings, invested in mines, property and energy projects.

In thousands of pages of corporate documents describing these ventures, the name that never appears is his own: Zhou Yongkang, the formidable Chinese Communist Party leader who served as China’s top security official and the de facto boss of its oil industry.

A visitor at the Zhou family's ancestral graves in Xiqliantou, eastern China. Intrigue surrounds the family after a spate of arrests. Sim Chi Yim for the New York Times

But President Xi Jinping has targeted Mr. Zhou in an extraordinary corruption inquiry, a first for a Chinese party leader of Mr. Zhou’s rank, and put his family’s extensive business interests in the cross hairs.

Even by the cutthroat standards of Chinese politics, it is a bold maneuver. The finances of the families of senior leaders are among the deepest and most politically delicate secrets in China. The party has for years followed a tacit rule that relatives of the elite could prosper from the country’s economic opening, which rewarded loyalty and helped avert rifts in the leadership.

Zhou Family Ties

Zhou Yongkang, a member of China’s ruling Politburo Standing Committee from 2007 to 2012, is the subject of one of the highest-level corruption investigations in the history of the People’s Republic of China. Several members of his family, over the years Mr. Zhou was in power, made investments in companies with ties to the China National Petroleum Corp., the state oil company formerly run by Mr. Zhou, although there is no evidence to show that Mr. Zhou was personally involved in the dealings.

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Fri

Nov

2015