Timeline: The US Oil Crisis, 1973-1974

more »

From Gretel Ehrlich’s Greenland notebook

I first traveled to Greenland in 1993 when the seasonal sea ice was 10 to 14 feet thick and the Greenland ice sheet hadn’t “thought” of melting. Arriving in Ummannaaq in the summer, I returned the next winter in the dark time, then returned again almost every year thereafter.

Soon I was traveling by dogsled on seasonal sea ice with subsistence hunters in the two northernmost villages in the world. We never imagined that sea level might rise of 70 feet, having grown up in a stable inter-glacial period; we had forgotten that Earth and its waters had undergone violent and extreme upheavals, periods of volcanism, ice, drought and flooding in the past, enough to cause mass extinctions and enormous changes not only to the planet, but to the “nations” of animals and humans who have resided here.

***********

Twenty years after my first visit to Greenland, I returned to Greenland with my partner, Neal Conan, who recorded and narrated the sounds of the Jacobshavn Glacier melting and calving, and to contemplate the demise of ice which is the natural air conditioner of the world.

The following are some of my notes from this adventure.

Greenland mapIlulissat — August 9, 2013
Two days ago, Neal and I left the burning forehead of the Wind River Mountains in front of our Wyoming cabin as we made our way to the west central coast of Greenland, to its singular mountain of ice, 11,000 feet high.

Once I thought of the ice sheet as a jewel, diamond-like and hard. Now, according to climatologist, Jason Box, who we met in Copenhagen, the Greenland ice sheet is melting at an accelerated pace.

“It’s not just surface melt,” he says, “but the deformation of inner ice. I’m tracking multiple feedbacks and connecting the dots. Beyond surface ice melt and the natural drainpipes called moulins, there’s a drawdown of the inner ice caused by impurities like soot and ash that darken the snow and ice, and thus reduce the albedo effect, and cause melting everywhere, inside and out. I call it my ‘Dark Snow Project.’ The whole fabric of the ice sheet is coming apart. Three hundred billion tons of ice is lost each year.”

August 10
Flying to Ilulissat from Kangerlusuuaq: green valleys, bare swipes of granite. Polished slabs pocked with the blue eyes of kettle ponds. Ice-blue meltwater. Green milk. Water from between the toes of hundreds of glaciers oozing down from the ice sheet that covers most of Greenland.

Melt ponds

Jakobshavn melt ponds

Glacial flour thickens. Meltwater is cerulean, then a blue so pale it seems like vanishing smoke. Just before landing we fly over a thick white ribbon of rough ice, studded with broken icebergs as if an entire city had collapsed and its rubble was being push toward the sea.

This is the Jacobshavn Glacier, whose collapse and accelerated calving rate has made it a World Heritage Site, as if to celebrate the death of this ice-island and the 5,000 year old Inuit culture that, against all odds, has thrived here.

Welcome to Ilulissat.

August 11
Ice is time. We’ve turned the clock forward, then back as we traveled from Wyoming to Copenhagen, then halfway back across the Atlantic Ocean to Greenland. The ice sheet used to be smooth, with large crevasses, and plains of snow-covered ice. Now it looks as if it had been shattered by a huge sledge hammer. The chaotic fracturing of an ice sheet and its glaciers is the signature of fast movement, of time squeezed, hastened, and released. To move glacially no longer implies “slowness,” but rather, the skidding forward of an ice sheet whose ravaged face keeps giving itself away.

View from plane

View from the plane

Afternoon
We board a small plane, piloted by Matthias, to fly over the ice sheet and see the face of the Jacobshavn Glacier. Below are icy cathedrals, shaped pieces of glass, fresh blue walls, strangled icebergs with rounded corners and meltwater dropping from their sun-ravaged wings like pieces of turquoise. For half an hour we traverse a wilderness of deeply sliced ice with dirty crevasses, blue slits, then on a slab of granite, a halved iceberg lying on its side as if thrown there and abandoned.

Finally we can see the face of the glacier itself, so far back it seems to have been torn from an unworldly landscape, all irregular blue teeth. There is no single line of ice, but a cubist face, roughly torn, and too wide to take it all in at one glance….

“From here on we’ll follow the fjord out to the sea,” Matthias says. Ahead is 103 miles of ice rubble, a carcass glinting with narrow stripes of turquoise. Down we go in a river of ice, a river that seems not to move at all, but does. Fingers of granite look liquid compared to the clotted ice-way.

Now there’s ocean ahead—-Disko Bay. Soon the strangled icebergs will be able to break off and drift freely. I see an iceberg crack open, its blue interior revealed. Displaced sea water glints in late afternoon sun. Water streams flow from many directions in a mesmerizing chaos. Chips of light dissolve: here we are at the end of time.

August 12
The people of Greenland, the Inuit, originally came from northeastern Siberia over 20,000 years ago. They walked and boated across the Bering Land Bridge and the seas that surrounded it with their spears and harpoons, their pack-dogs and skin boats. Slowly they moved across the polar north, from Point Hope, Alaska over frozen tundra to the MacKenzie Delta, across the entire Canadian Archipelago, now known as Nunavut, finally to Greenland.

A single culture; a single language with many dialects; the same legends and taboos; the same material culture with local variations and improvements, as dynamic as the ice, yet singular.

Greenland was the last Arctic nation to have come into the 21st century with much of its traditional hunting culture in tact. “We had everything,” Jens Danielsen said. “We speak only Greenlandic, we’ve kept our traditional hunting practices. We banned snowmobiles and travel only by Greenland-style dogsleds, hunt narwhal in the summer from kayaks with harpoons, wear polar bear pants and foxfur anoraks and sealskin kamiks. We make almost everything ourselves. All that we know is passed on to our children. Now it is being lost because of this new unstable climate. We are sending our children who were raised to be great hunters to the south of Greenland, below the Arctic Circle to learn a trade.

“We were taught to be modest in front of the weather. But this weather is not ours. Nine months of ice is now two or three. Eight years ago I said that it would be a disaster if we lost our ice. Now we have. Without ice we are nothing at all.”

Icebergs and water

Photos by Gretel Ehrlich

August 13
In the afternoon Neal and I walk from town up to the edge of the fjord. It’s here that we first understand the scale of the calved ice. Think warehouse, a city-block of ice, carved and port-holed, its broken sides polished and scratched as if silver threads had been sewn through it.

Under the arm of one berg, a row of candle ice tinkles. We’ve come here to listen to the way ice moves. Its cries and salutations. The sun roars around its elliptical route, now headed north. We sit on the granite cliff. In front of us, an enormous iceberg shines. Its base is smooth but it is topped with jagged ice, pointed slabs thrown together. Two thumping roars jolt us. The tide is going out. Ice-elbows slide and collapse.

Slack tide
A breeze comes up. Accordioned waves slap the cliff and are sent backwards. Ice streams pour out. A distant seagull cries and cries. Water moves in two directions simultaneously. Another tympanic sound. Like something hollow. Ice moves in a seeming motionless drift in tidal pulses we can only begin to detect. Muffled booms. We see nothing. Thunder emanates from deep inside the ice as if to verify all that Jason Box told us. We are all dying from the internal combustion of age and sunlight. Grinding and sloshing, turquoise ice returns to its liquid form.

End of day
An island of ice slides through the shadow of a bigger iceberg into the silvered evening light like a sword. Something snaps. Thunderous roar. Shhhhh….we are listening to glacier-talk: its howls and pops, its detonations and sonic death-throes.

August 14
By tourist boat north. A whale breaches. Gulls fly over, checking to see if we have halibut on board. Flocks of Arctic terns gather over coastal valleys and soar toward the Eqi Glacier. Here, we come very close to is calving face.

Boat and icebergsThe Captain turns off the engines. We listen: there’s the sound of rustling skirts. To our left an iceberg turns over. Displaced water rolls under us. Slabs of pale sapphire shoot up out of the water. Then it’s quiet. The boat jostles. A sound begins. A sound so loud it is almost white noise. We look. Where is it coming from?

To starboard a 300 ft. wall of ice begins to collapse..…shushhhhhhshushhhhhhshushhhhhhhh….. Now another one to port…. Two enormous walls as if two sides of a building was being demolished. Ice slides straight down into the sea….. shushhhshhshshshhshshhhhhhhhh. Two huge waves come at the boat. Big rolling humps….

I yell—“We should move back…this is dangerous.” But the captain only smiles. The boat heaves up, slaps down into the deep trough, and heaves up again. Bits of ice teeter on top and hit the steel hull. The water goes pale with glacial flour. Ice streams pour out and move icebergs toward and away from us. The deck does not flatten…we rock and roll as glacial till keeps slapping us. Sun fades behind a roll of mist. Glitter and chalk as bits of ice crumble from the new glacial face. We move away. Then we’re encased by a dull shroud.

The water smoothes out. Ahead, sun marks the way forward as we motor toward home. Behind us a fogbow marks the passageway through which we have journeyed, with its collapsing walls of ice and sounds of melting, but the arch of fog, the gateless gate, follows us all the way down the coast as if being towed.

–Gretel Ehrlich
August, 2013

more »

Future Sea Level

A break with the past

In the late 1990s, a dramatic event surprised and disturbed glaciologists around the world, increasing concern that global warming could cause Earth’s great ice sheets at the north and south poles to disintegrate rapidly and catastrophically. A frozen stream of ice in the Jakobshavn Glacier on Greenland’s west coast suddenly accelerated seaward. Already one of the world’s fastest moving glaciers, Jakobshavn doubled its speed.

jakobshavn

Jakobshavn glacier in 2013
Photo: Gretel Ehrlich

Mountainous blocks of ice broke off Greenland’s perimeter at a furious rate, clogging a 35-mile long fjord with icebergs bigger than aircraft carriers. Fortunately, Jakobshavn settled down several years later. But before it did, the glacier had expelled tens of billions of tons of ice into the Atlantic.

Scientists aren’t sure why Jakobshavn sped up, or tapered off later. They haven’t  been able to calculate the top speed that an ice stream like Jakobshavn could achieve. Nor can they specify the limit of how much mass such streams of ice in Greenland or Antarctica could cast into the sea. They’d dearly like to know, as many researchers believe the accelerated flow of solid ice in ice streams could dramatically increase the rate of sea level rise.  Until these questions are resolved, some researchers consider it possible that sea level rise later this century could be many feet.

Global warming basics

Earth is getting hotter. The planet has heated up by around 1.5 degrees Fahrenheit (0.8 degree Celsius) since the 1880s. When the oceans heat up, their water expands and creeps up shorelines. Higher temperatures also threaten mountain glaciers and the huge ice sheets at Earth’s north and south poles. Since extra heat also cranks up evaporation and precipitation, sometimes in the form of snow that compensates for melting, higher temperatures don’t necessarily always make glaciers shrink.

CO2 graphIn practice, though, scientists have discovered that all the world’s major glaciated mountain ranges including the Andes, the Himalayas, the Swiss Alps and the mountains of Alaska are losing ice. The continental-size ice sheets of the poles are shedding massive amounts of mass into the sea. As a result, sea level has gone up by about 4.5 inches (11 centimeters) since 1950. The rate at which sea level is increasing appears to be going up, though researchers can’t be sure until more time has passed.

About 40 percent of the world’s inhabitants work and farm and sleep within about 50 miles of a coastline. The sea laps the land of eight of the world’s top ten cities. As the sea rises, many of these people are threatened with increased flooding, storm damage and salt intrusion into groundwater. Billions of dollars of property and millions of lives are at risk.

How fast and how high might sea level grow in the future? Government planners and residents of coastal regions are among the many people who could plan better if they knew the answer. Scientists have made estimates of future sea level. But their results are uncertain because the task is complicated by the numerous factors that influence sea level rise.

Earth’s ice

Ice occurs naturally in various forms in many parts of the world. Each kind has its own particular relationship to global warming and sea level. When viewed from space, Earth’s most obvious feature, after the oceans, is, a vast white wintertime band of snow covering northern Asia, Europe and North America. Global warming will reduce the amount of land covered in snow. But that melted snow will have virtually no impact on sea level. That’s because the layer of snow is thin, and the volume of water in snow is dwarfed by the vastness of oceans.

icebergs

Icebergs near Greenland
Photo: Gretel Ehrlich

The second most noticeable form of frozen water on Earth is sea ice. Sea ice, as the name suggests, is water frozen on the ocean’s surface, generally near the poles. The amount of sea ice varies with the seasons. At its maximum extent, such ice covers about 10 million square miles of water, an area about the size of ten Australias. The amount of sea ice in the Arctic has been declining steadily for at least as long as systematic satellite monitoring began in the late 1970s. Many researchers predict that the Arctic will be virtually free of sea ice in summers before the middle of this century; perhaps much sooner.

The disappearance of sea ice will not alter sea level. That’s because sea ice floats, just like ice cubes in a drink. When a soda on the rocks warms up, the level of the surface remains fixed. (However, the loss of sea ice will have numerous other detrimental effects. Sea ice reflects sunlight back into space, whereas ocean water absorbs most sunlight that hits it. Less sea ice means a warmer Arctic. The temperature differential between the Arctic and equatorial regions, a major force behind Earth’s weather patterns, will be muted.

Moreover, sea ice performs important roles in polar ecosystems. Marine mammals such as some seals and polar bears depend on it as a platform for hunting and resting.  Many of the marine plants that form the foundation for the polar food chain, known as phytoplankton, also depend on sea ice for part of their life cycle.)

Unlike sea ice, the huge ice sheets of Antarctica and Greenland rest on land (or, in some cases, the seafloor). Sea level does rise when they melt. The ice sheets occupy less area than sea ice or snow, but they’re radically thicker (more than a mile, or about 1.6 kilometers, from top to bottom in places). All together, the polar ice sheets hold enough water to lift sea level by about 250 feet (76 meters). Mountain glaciers also raise sea level as they recede, which they’re doing, at a spectacular rate. But mountain glaciers hold only a small fraction of the water stored in polar ice sheets: only enough to raise sea level by about 2 feet (0.6 meters).

Unlike ice cubes

Because polar ice sheets are so massive, the rate at which they might melt has received concerted scientific attention. Still, many questions remain. If ice sheets behaved like an ice cube dropped out of a freezer tray on a summer day, predicting how fast they’d waste away—and how fast sea level would rise—would be relatively easy.

pullquote_coastIce cubes melt from the outside inward. As the exterior dribbles off, inner ice appears in an orderly fashion, like layers peeled off an onion. To predict the fate of ice melting this way requires taking into account factors like air temperature and the movement of air currents. Scientists know how to perform such calculations for ice cubes as well as for ice sheets. Researchers have estimated, roughly, that if all the world’s glaciers melted this way, sea level rise by about 15 inches (0.4 meters) by the end of the century. Sea level rise of this magnitude can’t be ignored, but it’s relatively small, and it would occur over many decades.

But, while behaving in part like ice cubes, ice sheets also waste away in a manner unlike any ice cube: from the inside out. Frozen ice streams convey an ice sheet’s bulk from the interior to the perimeter at the sea, sometimes hundreds of miles away.  At the edge of the ice sheet, great blocks shear off and fall into the water. An ice sheet flowing this way could lose volume much faster than one that suffers surface melting alone.

Alternate Approaches

There are two primary means of forecasting future sea level. In one, scientists create a mathematical model of sea level that takes into account how much water will expand and how much glaciers will grow or shrink. This method requires a detailed understanding of factors like how heat penetrates into the ocean’s depths, how changes in air temperature influences precipitation and, of course, the behavior of warming glaciers.  Researchers have created such models. But they suffer from uncertainty about how Earth’s complex parts work and relate to each other.

Blowing Rocks, Florida

Blowing Rocks Preserve, Florida

The other major way that scientists try to predict future ocean inundation is by studying sea level in Earth’s past, when the planet was as warm or warmer than today. For the last two million years or so, Earth has cycled more than a dozen times between ice ages and warm periods. The last ice age ended about 12,000 years ago. Scientists think these temperature swings are controlled in part by changes in Earth’s orbit around the sun. During an ice age, billions of tons of water freezes on mountaintops and at the poles.  Sea level falls hundreds of feet. During a warm period, in contrast, this ice melts, ocean basins swell with the extra liquid, and the seas rise.

Climate researchers are especially interested in how high the sea rose during previous warm periods, prior to the most recent ice ages. Several such epochs have been hotter than today, making them possible analogs to our warmer future. The most recent warm period, about 100,000 years ago, was 2 to 4 degrees Fahrenheit (1 to 2 degrees Celsius) warmer than today. Many scientists believe that sea level was 15 to 20 feet higher then.

Choosing whether to act

Earth’s temperature will rise sharply unless steps are taken to reduce significantly the amount of fossil fuel burned to make electricity, power vehicles and to heat homes. We’ll have to make heroic efforts to prevent global temperature from reaching or surpassing that of the last warm period.

If Earth does get that hot, many scientists believe that sea level will rise to the level it reached during that earlier spell. They readily admit, however, that they can’t predict how quickly the sea would go up.

They’ve uncovered evidence that within the past 20,000 years sea level has gone up at a rate as fast as 12 feet (4 meters) per century. However they can’t say if global warming could cause sea level to rise that quickly in the future.

 

Dan Grossman is print journalist and radio and web producer. You can see more of his work on the extensive Sea Change website.

 

more »

The melting of Greenland

greenland_map_v2

Neal Conan – former NPR host and correspondent – went to Greenland for a closer look at the island’s melting ice. One of his guides was acclaimed science and nature writer Gretel Ehrlich.

more »

What IPCC’s climate report says about rising sea levels

Lauren Sommer, BURN Contributor

No one was too shocked by the latest climate projections released in the Intergovernmental Panel on Climate Change’s (IPCC) fifth report on Friday. The United Nations-created group is responsible for a sort of climate change “master doc,” collating studies from around the globe into a general consensus with the help of thousands of scientists.

 What did they find? Global temperatures are on the rise and we’re to blame. Or, in scientific speak, the panel said it’s “extremely likely” (greater than 95 percent certainty) that the warming is primarily due to human influence (burning fossil fuels and pumping carbon into the atmosphere). “There is a need for us to reduce emissions of greenhouse gases substantially if we really want to stabilize the Earth’s climate and I hope this is a message that the world will receive and accept,” said IPCC chairman Rajendra Pachauri.

IPCCchart1One topic did grab headlines: rising sea level. On average, it’s already gone up about seven inches since 1900, but the rate of change is expected to speed up. Under a worst-case scenario with unchecked greenhouse gas emissions, sea levels could rise 20 to 38 inches by the end of the century. That’s higher than the IPCC assessed in its last report six years ago, which put it from 10 to 23 inches.

Why the difference? It has to do with the two different factors that cause sea level rise. One is based on a basic tenet of physics: as water gets warmer, it expands. That’s caused about 40 percent of the sea level rise they can account for over the last decade.

The other cause of sea level rise is a little trickier for scientists to sort out. Glaciers and the Greenland and Antarctic ice sheets contain massive amounts of water, and they’re melting. That makes the ice sheets the “ticking time bombs” of climate change, according to some. Complete loss of the Greenland ice sheet, something the report says is possible with sustained warming over a millennium, would cause sea levels to rise by 23 feet.

IPPCchart2

The Greenland ice sheet is losing ice at a faster and faster pace, but in its previous report, the IPCC excluded some of that information from its sea level rise projections, saying not enough was known about the melting process to model it accurately. The state of the science has improved, the panel says, hence the jump in the numbers.

Other studies in the scientific community put sea level rise projections even higher. The IPCC acknowledged that, but found “there is no consensus currently in the scientific community about these very high sea level projections over the next 100 years,” according to Thomas Stocker, co-chair of the IPCC working group that released the report.

As was seen with Superstorm Sandy, the economic cost of storm surges and flooding runs into the billions and may only be a taste of what’s predicted for New York City and other places around the globe. More details about the sea level rise scenarios and the strategies to reduce carbon emissions are expected as the IPCC rolls out the rest of its assessment over the next year.

Lauren Sommer reports on environment, science and energy for KQED Public Radio in San Francisco. All graphics from IPCC.

more »