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Scientists Alarmed as Delaware-Sized Iceberg Breaks Off Antarctic Ice Shelf

By Ilissa Ocko and Mason Fried

Scientists watched with alarm this week as the fourth-largest ice shelf in Antarctica rapidly broke apart, causing an enormous, Delaware-size iceberg to float into the Southern Ocean.


After observing an anomalous rift widening across a section of the so-called Larsen C ice shelf for the past several years, researchers are left with some critical questions: What are this event's broader consequences for the Antarctic ice sheet, what happens next, and—importantly—what role did climate change play here?

For now, this event serves as yet another reminder that Antarctica is changing rapidly—and that action to curb rising global temperatures is critical.

Antarctica: A frontline for climate change

So far, scientists have been hesitant to attribute the Larsen C ice shelf breakup to rising global temperatures.

Indeed, such events—known to scientists as "calving"—occur naturally and are essential for maintaining ice shelf balance. Without them, ice shelves would grow unabated to cover large swaths of the Southern Ocean.

Still, the magnitude and timing of this ice loss warrants attention.

The Antarctic Peninsula, where the Larsen ice shelves reside, has long been viewed as a frontline for climate change. Warming in the peninsula exceeds the global average, glaciers there are retreating, and two other ice shelves on the peninsula already collapsed over the past couple of decades after being stable for thousands of years.

Such changes will help raise global sea levels by three to six feet by 2100, projections show, affecting dense coastal communities along our Eastern Seaboard and across the globe.

Ice breakup starts chain reaction

We do know that this calving event could set in motion a string of chain reactions that further destabilize the ice shelf and surrounding glaciers, and ultimately contribute to global sea level rise.

Ice shelves are floating extensions of grounded glaciers and ice sheets that, importantly, buttress and impede inland ice flow. When an ice shelf collapses or becomes weaker, this defense disappears, allowing inland glaciers to accelerate downslope and transport more ice to the ocean, which can quickly affect sea level.

Scientists worry that the remnant Larsen C ice shelf will now be at considerable risk of further breakup.

The new calving event reduced the ice shelf area by more than 10 percent, leaving behind an ice shelf that is inherently unstable. This can, in turn, trigger new ice cracks and rifting, and cause more icebergs to break off—further increasing the possibility of runaway ice loss amid rising global temperatures.

Whether or not this latest calving event will be attributed to climate change, it's safe to say that it will make the region more vulnerable to the impacts of global warming.

Climate change caused 2002 ice shelf collapse

The Larsen C ice shelf, named for a Norwegian whaling vessel captain who sailed the Southern Sea in the late 1800s, has two smaller northern neighbors known as Larsen A and Larsen B—both of which collapsed in the past 23 years.

Those events taught us that ice sheets, landscapes we used to think of as stable and slow to change, can actually transform rapidly.

The Larsen B collapse was particularly dramatic, with nearly the entire ice shelf disintegrating during a three-week period in 2002 after remaining stable for at least 10,000 years.

The speed of that event was unprecedented and attributed directly to increasing atmospheric warming, although rising ocean temperatures and long-term ice loss from surrounding glaciers may also have played a role.

A hint of what's to come?

After the Larsen B shelf collapse, researchers observed dramatic increases in glacier speed, thinning and ice transfer to the ocean.

Some researchers are already drawing parallels between this week's Larsen C collapse and the series of events that led to the eventual collapse of Larsen B. The latter experienced a similar large calving event in 1995 that foreshadowed further retreat and widespread disintegration in 2002.

While it remains to be seen if and when Larsen C will meet the same fate, warning signs are already in place. What's happening to the Larsen ice shelves could, in fact, be a proxy for what's to come across even larger sections of the Antarctic ice sheet unless we take action to slow warming.

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Kevin Vallely

'Rowing the Northwest Passage' Chronicles An Expedition Through the Changing North

By Kevin Vallely

In 2013 four adventurers set out on an 80-day rowboat mission through the Arctic's rapidly melting Northwest Passage. Their journey brought them face to face with the changing seas in a world of climate change. In this excerpt from adventurer Kevin Vallely's new book about the expedition, Rowing the Northwest Passage (Greystone Books), we also see how climate change has affected some of the people the team met along their journey:

An elderly woman walks toward us from the road. Tuktoyaktuk, in the Northwest Territories, is a sizable town by Arctic standards, with a full-time population of 954, but it's small enough that the bulk of the town likely knows we're here. The woman is smiling when she reaches us.

"I saw you coming in," she says. "Where you guys come from?" "We're from Vancouver," I say, my mouth still half full of food. "We started our trip in Inuvik nine days ago." Her name is Eileen Jacobsen and she's an Elder in town. She and her husband, Billy, run a sightseeing business. "You should come up to the house in the morning and have some coffee," she tells us.

Our night's sleep in the Arctic Joule is fitful; our overindulgence runs through all of us like a thunderstorm. By seven in the morning, even with both hatches open, lighting a match in the cabin would blow us out like dirt from that Siberian crater. The roar of the Jetboil pulls me out. Frank's already up, down jacket on, preparing coffee. "You like a cup?"

It's still too early to drop by Eileen Jacobsen's house, so we walk into town on the dusty main road, our ears assaulted by a cacophony of barking dogs. Dirt is the surface of choice for roads and runways in Arctic communities, as any inflexible surface like concrete would be shredded by the annual freeze–thaw cycle. Most of the town runs the length of a thin finger of land, with the ocean on one side and a protected bay on the other. About halfway down the peninsula, a cluster of wooden crosses rests in a high grass clearing, facing west. We heard about this graveyard in Inuvik. Because of melting permafrost and wave action, it's eroding into the sea, and community members have lined the shore with large rocks to forestall its demise. This entire peninsula will face this threat in the coming years. There's not much land here to hold back a hungry ocean.

We notice an elderly man in a blue winter jacket staring at us a short distance away. He's sitting outside a small wooden house and smiles as we approach. "You guys must be the rowers," he says. "Too windy to be out rowing." His jacket hood is pulled tight over his ball cap and he dons a pair of wraparound shades with yellow lenses that would better suit a racing cyclist than a village Elder. His name is Fred Wolki, and he's lived in Tuk for the last fifty years. "I grew up on my father's boat until they sent me to school in 1944, then I came here."

His father, Jim Wolki, is a well-known fox trapper who transported his pelts from Banks Island to Herschel Island aboard his ship the North Star of Herschel Island. Interestingly, we had the Arctic Joule moored right beside the North Star at the Vancouver Maritime Museum before we left. Built in San Francisco in 1935, the North Star plied the waters of the Beaufort Sea for over thirty years, her presence in Arctic waters playing an important role in bolstering Canadian Arctic sovereignty through the Cold War.

"We're curious if things have changed much here since you were a boy," Frank says.

"Well … it's getting warmer now," Fred says, shaking his head. He gestures out to the water speaking slowly and pausing for long moments between thoughts. "Right up to the 1960s … there was old ice along the coast … The ice barely moved … It was grounded along the coastline." He looks out over the shoreline, moving his arm back and forth. "They started to fade away slowly in the 1960s … icebergs … They were huge, like big islands … They were so high, like the land at the dew Line station … over there." He points to the radar dome of the long decommissioned Distant Early Warning Line station that sits on a rise of land just east of us. "It's been twenty years since we've seen one in Tuk." There's no sentimentality or anger in Fred's voice; he's just telling us his story. "It's getting warmer now … Global warming is starting to take its toll … All the permafrost is starting to melt … Water is starting to eat away our land."

I listen to his words, amazed. There's no agenda here, no vested interest, no job creation or moneymaking—just an elderly man bearing witness to his changing world.

Excerpted from Rowing the Northwest Passage: Adventure, Fear, and Awe in a Rising Sea by Kevin Vallely, published September 2017 by Greystone Books. Condensed and reproduced with permission from the publisher.

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Hundreds Dead in Mexico After Earthquake Strikes on Anniversary of Devastating 1985 Quake

In Mexico, a massive 7.1-magnitude quake struck 100 miles southeast of Mexico City Tuesday, collapsing dozens of buildings around the capital city and trapping schoolchildren, workers and residents beneath the rubble.

At least 217 people are dead, and hundreds more are missing. Among the dead are least 21 students at a primary school in Mexico City and 15 worshipers who died during a Catholic mass when the earthquake triggered an eruption at a volcano southeast of the city.

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Fourth St. sign under water in San Francisco. Scott Schiller/Flickr

San Francisco Becomes First Major U.S. City to Sue Fossil Fuel Industry Over Costs of Climate Change

San Francisco and Oakland are suing Chevron, ConocoPhillips, ExxonMobil, BP and Royal Dutch Shell—the five biggest investor-owned fossil fuel producers in the world—over the costs of climate change.

The two Californian cities join the counties of Marin, San Mateo and San Diego and the city of Imperial Beach that have taken similar legal action in recent months, the San Francisco Chronicle reports.

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Climate Alliance States Show Us What Real Leadership Looks Like

By Luis Martinez and Kit Kennedy

In a forceful show of climate leadership, Governors Andrew Cuomo (NY), Jerry Brown (CA), and Jay Inslee (WA) and former Secretary of State John Kerry came together in New York City Wednesday as part of Climate Week to celebrate the progress and growth of the U.S. Climate Alliance, the bipartisan coalition that has grown to 14 states dedicated to meeting the Paris agreement climate goal. The coalition was founded by Cuomo, Brown and Inslee after President Trump announced the U.S. intent to withdraw from Paris.

President Trump may prefer to pretend that climate change isn't real—Gov. Cuomo quipped that the Trump administration is in "the State of Denial"—but these leaders detailed the extraordinary strides they're making, in the absence of White House leadership, to slash greenhouse gas emissions and grow their economies at the same time. For New Yorkers, it's exciting to see Cuomo's leadership on clean energy and climate continue to accelerate, from setting strong renewable energy goals, to a successful push with other Regional Greenhouse Gas Initiative states to further slash carbon emissions, to banning fracking.

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Hurricane Maria Devastates Puerto Rico

By Andy Rowell

As new Hurricane Maria brings devastation to Puerto Rico, the governor of the island, Ricardo Rossello, has asked Donald Trump to declare the U.S. territory a disaster zone.

He has said that Maria could be the most damaging hurricane to hit the country in more than 100 years.

With maximum recorded wind speeds of 140 mph and rainfall of up to 25 inches or even higher, Mike Brennan, a senior hurricane specialist from the U.S. National Hurricane Center has also warned locals of flash-flooding and "punishing" rainfall. He added that the storm would remain "very dangerous" for the next couple of days.

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Nicaragua to Sign Paris Agreement, Leaving Trump Alone With Syria

When President Donald Trump decided to pull out of the Paris climate agreement in June, the United States joined the only two countries of the 197 nations in the U.N. Framework Convention on Climate Change that declined to sign the 2015 accord: Syria, which has been embroiled in a full-scale civil war for six years; and Nicaragua, as its leaders felt the pact was not strong enough to fight climate change.

But now, Nicaraguan President Daniel Ortega said his country will sign the agreement "soon," Managua-based TV station 100% Noticias reports.

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14 States On Track to Meet Paris Targets

Fourteen states and Puerto Rico are on track to meet and potentially exceed their portion of the U.S. commitment under the Paris agreement.

The report shows that the member states of the U.S. Climate Alliance (USCA), which has grown to represent 36 percent of the U.S. population and more than $7 trillion of America's GDP, are collectively on track to reach a 24 to 29 percent reduction below 2005 emissions levels by 2025.

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Leonardo DiCaprio Foundation Awards $20M in Largest-Ever Portfolio of Environmental Grants

Environmental activist and Oscar-winning actor Leonardo DiCaprio announced that his foundation has awarded $20 million to more than 100 organizations supporting environmental causes.

This is the Leonardo DiCaprio Foundation's (LDF) largest-ever portfolio of environmental grants to date. The organization has now offered more than $80 million in total direct financial impact since its founding in 1998.

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