New study finds sea level rise accelerating

February 13 2018 - The rate of global sea level rise has been accelerating in recent decades, rather than increasing steadily, according to a new study based on 25 years of NASA and European satellite data.

This acceleration, driven mainly by increased melting in Greenland and Antarctica, has the potential to double the total sea level rise projected by 2100 when compared to projections that assume a constant rate of sea level rise, according to lead author Steve Nerem. Nerem is a professor of Aerospace Engineering Sciences at the University of Colorado Boulder, a fellow at Colorado's Cooperative Institute for Research in Environmental Sciences (CIRES), and a member of NASA's Sea Level Change team.

Global sea level rise is accelerating incrementally over time rather than increasing at a steady rate, as previously thought, according to a new study based on 25 years of NASA and European satellite data.

If the rate of ocean rise continues to change at this pace, sea level will rise 26 inches (65 centimeters) by 2100 — enough to cause significant problems for coastal cities, according to the new assessment by Nerem and colleagues from NASA's Goddard Space Flight Center in Greenbelt, Maryland; CU Boulder; the University of South Florida in Tampa; and Old Dominion University in Norfolk, Virginia. The team, driven to understand and better predict Earth's response to a warming world, published their work Feb. 12 in the journal Proceedings of the National Academy of Sciences.

"This is almost certainly a conservative estimate," Nerem said. "Our extrapolation assumes that sea level continues to change in the future as it has over the last 25 years. Given the large changes we are seeing in the ice sheets today, that's not likely."

Rising concentrations of greenhouse gases in Earth's atmosphere increase the temperature of air and water, which causes sea level to rise in two ways. First, warmer water expands, and this "thermal expansion" of the ocean has contributed about half of the 2.8 inches (7 centimeters) of global mean sea level rise we've seen over the last 25 years, Nerem said. Second, melting land ice flows into the ocean, also increasing sea level across the globe. Read More

Worst-case global warming predictions are the most accurate, say climate experts

Current predictions of climate change may significantly underestimate the speed and severity of global warming, according to a new study.

Reappraisal of the models climate scientists use to determine future warming has revealed that less optimistic estimates are more realistic.

The results suggest that the Paris Climate Agreement, which aims to keep global average temperatures from rising by 2C, may be overly ambitious.

“Our study indicates that if emissions follow a commonly used business-as-usual scenario, there is a 93 per cent chance that global warming will exceed 4C by the end of this century,” said Dr Ken Caldeira, an atmospheric scientist at the Carnegie Institution for Science, who co-authored the new study.

This likelihood is an increase on past estimates, which placed it at 62 per cent. https://goo.gl/5jgsrd

Not if the Seas Rise, but When and How High

Once you’ve read an excellent book about climate change, which Jeff Goodell’s “The Water Will Come” most certainly is, you can never unremember the facts. Elected officials may be busy arguing about whether global warming is real. But most scientists are having other arguments entirely — about whether danger is imminent or a few decades off; about whether our prospects are dire or merely grim.
“Sea-level rise is one of the central facts of our time, as real as gravity,” Goodell writes. “It will reshape our world in ways most of us can only dimly imagine.”
Goodell has little trouble imagining it. He opens “The Water Will Come” with a fictional hurricane whipping through Miami in 2037. It sweeps the Art Deco buildings of South Beach off their foundations, disgorges millions of gallons of raw sewage into Biscayne Bay and eats the last of the city’s beaches. Thousands scramble for bottled water dropped by the National Guard. Zika and dengue fever start to bloom (so much moisture, so many mosquitoes). Out rush the retirees and glamour pusses; in rush the lawyers and slumlords. Within decades, the place is swallowed whole by the ocean. What was once a vibrant city is now a scuba-diving destination for intrepid historians and disaster tourists.
The whole scenario seems indecently feasible by the book’s end.
After this year’s calamitous flooding in Houston and the Caribbean, “The Water Will Come” is depressingly well-timed, though I’m guessing all good books about this subject will be from now on. Political time now lags behind geological time: If we don’t take dramatic steps to prepare for the rising seas, hundreds of millions could be displaced from their homes by the end of the century, and the infrastructure fringing the coast, valued in the trillions of dollars, could be lost.
Unfortunately, human beings are uniquely ill-suited to prepare for disasters they cannot sense or see. “We have evolved to defend ourselves from a guy with a knife or an animal with big teeth,” Goodell writes, “but we are not wired to make decisions about barely perceptible threats that gradually accelerate over time.”
So we stick our heads in the sand. Until the sand disappears, anyway.
https://goo.gl/8wuqjb

Climate change is altering Greenland ice sheet, accelerating sea level rise

The Greenland ice sheet has traditionally been pictured as a bit of a sponge for glacier meltwater, but new research has found it is rapidly losing the ability to buffer its contribution to rising sea levels, says a York University researcher.

York U Professor William Colgan, a co-author on the study published in the journal Nature Climate Change, helped analyse data from three expeditions to the Greenland ice sheet in 2012, 2013 and 2015. The research was done in conjunction with lead researcher Horst Machguth of the Geological Survey of Denmark and Greenland, Mike MacFerrin of the University of Colorado at Boulder and Dirk van As of the Geological Survey of Denmark and Greenland Copenhagen, Denmark.

Colgan spent five weeks with the team in 2013 drilling firn cores in the interior of the Greenland ice sheet. Firn is multi-year compacted snow that is not as dense as glacier ice. Instead, it forms a porous near-surface layer over the ice sheet. Dropped off by a ski-equipped US Air National Guard C-130 Hercules in minus 40 degrees Celsius weather, with 6,000 kilos of supplies and equipment, the team set up several camps and drilled a series of shallow firn cores about 20 metres deep during their time on the ice sheet.

"We were interested in the thin porous near-surface firn layer, and how its physical structure is changing rapidly with climate change," said Colgan of the Lassonde School of Engineering. "The study looked at very recent climate change on the ice sheet, how the last couple of years of melt have really altered the structure of the ice sheet firn and made it behave differently to future melt."

The researchers also towed a radar unit behind their skidoos to gather profiles between core sites along a 100-kilometre path from the low elevation ice sheet margin into the high elevation ice sheet interior. They analysed the firn cores on the spot by cutting them into small sections to quantify their properties, such as their density, so they could compare them with samples collected the following year. "The year-on-year firn changes were quite dramatic," said Colgan.

The team was surprised by what they found. An extreme melt that occurred in 2012 caused a layer of solid ice, several metres thick, to form on top of the porous firn in the low elevation areas of the ice sheet. "In subsequent years, meltwater couldn't penetrate vertically through the solid ice layer, and instead drained along the ice sheet surface toward the ocean," said Colgan. "It overturned the idea that firn can behave as a nearly bottomless sponge to absorb meltwater. Instead, we found that the meltwater storage capacity of the firn could be capped off relatively quickly."

As Machguth said, "Basically our research shows that the firn reacts fast to a changing climate. Its ability to limit mass loss of the ice sheet by retaining meltwater could be smaller than previously assumed."

Because the models scientists use to project Greenland's sea level rise contribution do not presently take firn cap-off into consideration, it means that Greenland's projected sea level rise due to meltwater runoff is likely higher than previously predicted. Getting this newly observed physical process into these models is an important next step for the team.

Using unmanned aerial vehicles, Colgan also plans to begin surveying the changes in ice sheet surface reflectance caused by the development of massive ice layers associated with firn cap-off. There are preliminary indications that firn cap-off is also occurring in the ice caps of the Canadian High Arctic. More

 

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Saving trees in tropics could cut emissions by one-fifth, study shows

Reducing deforestation in the tropics would significantly cut the amount of carbon dioxide emitted into the atmosphere -- by as much as one-fifth -- research shows. In the first study of its kind, scientists have calculated the amount of carbon absorbed by the world's tropical forests and the amounts of greenhouse gas emissions created by loss of trees, as a result of human activity.

Reducing deforestation in the tropics would significantly cut the amount of carbon dioxide emitted into the atmosphere -- by as much as one-fifth -- research shows.

In the first study of its kind, scientists have calculated the amount of carbon absorbed by the world's tropical forests and the amounts of greenhouse gas emissions created by loss of trees, as a result of human activity.

They found that tropical forests absorb almost two billion tonnes of carbon each year, equivalent to one-fifth of the world's carbon emissions, by storing it in their bark, leaves and soil. However, an equivalent amount is lost through logging, clearing of land for grazing, and growing biofuel crops such as palm oil, soya bean and sugar. Peat fires in forests add significantly to the greenhouse gas emissions.

Researchers estimate that if all human-related deforestation of the tropics were to stop, the forests could absorb more carbon than at present, equivalent to one-fifth of global emissions.

Researchers say carbon emissions from tropical forests will increase as the climate warms, as rising temperatures accelerate the decay of dead plants and trees, giving off more CO2. Global temperatures are forecast to rise by two degrees by the year 2099, which is predicted to increase annual carbon emissions from the forest by three-quarters of a billion tonnes.

Scientists from the Universities of Edinburgh and Leeds analysed data from multiple previous studies, including satellite studies, to determine the amount of carbon absorbed and emitted by the world's tropical forests in South and Central America, equatorial Africa and Asia.

Their study, published in Global Change Biology, was supported by the Natural Environment Research Council.

Professor John Grace of the University of Edinburgh's School of GeoSciences, who led the study, said: "If we limit human activity in the tropical forests of the world, this could play a valuable role in helping to curb the rise in carbon dioxide in the atmosphere. Preventing further losses of carbon from our tropical forests must remain a high priority." More

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Story Source:

The above story is based on materials provided by University of Edinburgh. Note: Materials may be edited for content and length.

Journal Reference:

1. John Grace, Edward Mitchard, Emanuel Gloor. Perturbations in the carbon budget of the tropics. Global Change Biology, 2014; DOI: 10.1111/gcb.12600

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© 2014

Antarctica's ice collapse threatens metres of sea level rise within decades

Scientists know that if Antarctica's ice sheets and glaciers collapse, sea levels could rise 5 metres. But the idea that it will take 200 years to happen is based on a linear model, writes Dady Cherry. In fact, the process is exponential - and could take place 'within decades'.

We conclude that this sector of West Antarctica is undergoing a marine ice sheet instability that will significantly contribute to sea level rise in decades to come.

Imagine further that a thick layer of ice covers, not only the surface of the island that lies above the sea but also an extensive portion of the perimeter that is beneath the sea.

The peaks are higher above sea level than on any continent. In winter, the sea freezes because temperatures drop to less than -80 degrees Celsius (-112 degrees Farenheight), and the island's area grows to about 10 million square miles.

In summer when some of the ice melts, the ice cover remains on average more than a mile thick, although the overall surface area of the island shrinks to about 5 million square miles. Even in summer, however, the island is still larger than Europe or Australia. It is Antarctica, and it is impossible to imagine.

When glaciers no longer rest on bedrock, they are doomed

So let us instead consider an island that is a large glacier with a thick cover of ice that extends outward, well beyond its land area. The island is shaped roughly like an infinity symbol, with the right (east) side much larger than the left (west).

The west side is really a peninsula and archipelago that share a common bedrock, but this is invisible because of the ice cover. What we can see is that even at the perimeter, where there is no land above sea level, there is ice. In some places, the ice reaches down, well beneath the water surface, all the way to the bedrock.

This situation is unstable, because in principle, the mass of ice that is beneath the sea and in continuous contact with liquid water should eventually melt. When it does, this initially leaves an overhanging shelf of ice over the water at the island's perimeter.

Being less dense than water, this shelf will want to float up and, given enough time, will eventually break away from the more interior ice that is pinned to land above sea level. Indeed, about 40% of Antarctica's perimeter consists of such ice shelves. In another 40% of the perimeter, the ice cover reaches all the way down to the bedrock.

An uncomfortable equilibrium is coming to an end

Island, ice and sea have coexisted for millennia in an uncomfortable equilibrium. In particular, the sea temperatures have not grown sufficiently warm to erode the ice edge irreversibly.

Furthermore, the mass of ice on the surface has remained relatively constant, with the seasonal flows of water out to sea in the summer being replaced by deposits of ice in winter.

The ice shelves have not thinned sufficiently to become so weak that they would snap and float away out to sea. This was all before the one-degree Celsius warming in the Earth's surface since around 1980.

Currently, the warmer seawater is eroding the island's submerged perimeter of ice. Simultaneously, the warmer air is also melting the ice cover at such an accelerated rate that it cannot be entirely replaced in the winters.

The process is irreversible

Once both kinds of erosion become irreversible, meaning that no net ice is replaced, the ice mass will shrink and become more and more bare, in a process that will accelerate out of control until the ice appears suddenly to vanish.

This is more or less the story that Eric Rignot and his colleagues reported about West Antarctica in a Geophysical Research Letters article that was accepted for publication on May 12, 2014.

They used satellite-based radar interferometry to map the edges of a series of glaciers that drain into a large bay called the Amundsen Sea Embayment, and combined their data with the results of other kinds of surveys.

Beating a rapid retreat

They discovered that between 1992 and 2011:

• Thwaites Glacier retreated 8.7 miles (14 km) at its core and zero to six miles (1 to 9 km) at its edges,
• Haynes Glacier retreated 6 miles (10 km) at its edges,
• Smith / Kohler Glacier retreated about 22 miles (35 km), and its ice shelf is barely pinned to the surface.
• Pine Island Glacier retreated 19 miles (31 km) at its center and snapped and detached from the ground.

All these retreats occurred mostly between 2005 to 2009. The authors note that they must have had a common cause and that the most reasonable explanation is the general warming of the ocean. They further explain that there is no natural land mass to prevent the movement of the massive glaciers out to sea. They conclude:

"The retreat is proceeding along fast-flowing, accelerating sectors that are thinning, become bound to reach floatation and un-ground from the bed.

"We find no major bed obstacle upstream of the 2011 grounding lines that would prevent further retreat of the grounding lines farther south.

"We conclude that this sector of West Antarctica is undergoing a marine ice sheet instability that will significantly contribute to sea level rise in decades to come."

In other words, the disappearance of West Antarctic ice is well under way, and it is irreversible.

The melting is exponential, not linear

It is notable that this research was done under difficult circumstances. For example, the authors write that, since 2001, the ERS-2 satellite has operated without its gyroscopes, and "This made it difficult to control the antenna pointing ... ".

They further observe that "In July 2011, ERS-2 terminated its mission after 16 years of services, far exceeding its planned operational lifespan."

In addition, they make a point of acknowledging "two anonymous reviewers for their comments." Possibly, the report was delayed, and some of its more frightening arguments had to be removed before publication.

In a later publication for the general public, Rignot stressed that the estimate of 200 years for the Radmunsen sea collapse, which has been repeated again and again in the press, is based on the melting continuing at its current rate.

This we know to be impossible because the melting is an exponential process that has been accelerating all the time and will continue to accelerate even more.

How long before sea rise is catastrophic?

The acceleration is driven, among other things, by an accelerated warming of the atmosphere and sea surface, continued expansion of the ozone hole, strengthening of currents that bring greater masses of warm waters from the tropics to Antarctica, weakening of the ice shelves due to accelerated melting of the surface ice, weakening of the attachment of the ice below sea level due to an accelerated erosion, and decreasing reflectivity of the Earth.

With regard to climate change, again and again, exponential processes have been treated as if they would develop linearly, despite scientists knowing quite well that they would not. Consider for example, a storm that is approaching your house from six miles away.

The storm is currently moving at five miles per hour, but it is expected to double its speed with every new mile. Do you make sure to have cover within one hour and 12 minutes, or within about 22 minutes?

Again and again, scientists have done the equivalent of feigning surprise when their timelines, based on a completely bogus linearity, have turned out to be too long. Things have gone much too far for us to continue to play such numbers' games.

West Antarctic ice sheet could raise sea levels 5m 'within decades'

Rignot blames carbon emissions, which have tripled since the Kyoto Protocol, for the current state of affairs, and he categorically says that the collapse of the ice cover from "the Amundsen sea sector of West Antarctica [is] unstoppable, with major consequences - it will mean that sea levels will rise one metre [more than 3 feet] worldwide.

"What's more, its disappearance will likely trigger the collapse of the rest of the West Antarctic ice sheet, which comes with a sea level rise of between three and five metres [10 to more than 16 feet]. Such an event will displace millions of people worldwide."

The sea-level rise of 10 to 16 feet will come in decades, rather than 200 years. It will submerge essentially every port city in the world, including Guangzhou, Mumbai, Shanghai, Ho Chi Minh City, Kolkata, Osaka-Kobe, Alexandria, New York, New Orleans, Miami, and indeed all of South Florida.

This will likely displace over 300 million people, many of them in countries that have equated development with movement of the majority of their populations to low-elevation coastal zones in port cities.

What other impacts will follow?

The displacement and homelessness from the changes in sea level might be the least of humanity's problems. More

 

© 2014

A Call to Arms: An Invitation to Demand Action on Climate Change

This is an invitation, an invitation to come to New York City. An invitation to anyone who'd like to prove to themselves, and to their children, that they give a damn about the biggest crisis our civilization has ever faced.

My guess is people will come by the tens of thousands, and it will be the largest demonstration yet of human resolve in the face of climate change. Sure, some of it will be exciting – who doesn't like the chance to march and sing and carry a clever sign through the canyons of Manhattan? But this is dead-serious business, a signal moment in the gathering fight of human beings to do something about global warming before it's too late to do anything but watch. You'll tell your grandchildren, assuming we win. So circle September 20th and 21st on your calendar, and then I'll explain.

Since Ban Ki-moon runs the United Nations, he's altogether aware that we're making no progress as a planet on slowing climate change. He presided over the collapse of global-climate talks at Copenhagen in 2009, and he knows the prospects are not much better for the "next Copenhagen" in Paris in December 2015. In order to spur those talks along, he's invited the world's leaders to New York in late September for a climate summit.

But the "world's leaders" haven't been leaders on climate change – at least not leaders enough. Like many of us, they've attended to the easy stuff, but they haven't set the world on a fundamentally new course. Barack Obama is the perfect example: Sure, he's imposed new mileage standards for cars, but he's also opened vast swaths of territory to oil drilling and coal mining, which will take us past Saudi Arabia and Russia as the world's biggest petro producer.

Like other world leaders, that is, he's tried, but not nearly hard enough. Consider what he told The New Yorker in an interview earlier this year: "At the end of the day, we're part of a long-running story. We just try to get our paragraph right." And "I think we are fortunate at the moment that we do not face a crisis of the scale and scope that Lincoln or FDR faced."

We do, though; we face a crisis as great as any president has ever encountered. Here's how his paragraph looks so far: Since he took office, summer sea ice in the Arctic has mostly disappeared, and at the South Pole, scientists in May made clear that the process of massive melt is now fully under way, with 10 feet of sea-level rise in the offing. Scientists have discovered the depth of changes in ocean chemistry: that seawater is 30 percent more acidic than just four decades ago, and it's already causing trouble for creatures at the bottom of the marine food chain. America has weathered the hottest year in its history, 2012, which saw a drought so deep that the corn harvest largely failed. At the moment, one of the biggest states in Obama's union, California, is caught in a drought deeper than any time since Europeans arrived. Hell, a few blocks south of the U.N. buildings, Hurricane Sandy turned the Lower East Side of New York into a branch of the East River. And that's just the United States. The world's scientists earlier this spring issued a 32-volume report explaining exactly how much worse it's going to get, which is, to summarize, a lot worse even than they'd thought before. It's not that the scientists are alarmists – it's that the science is alarming. Here's how one Princeton scientist summarized the situation for reporters: "We're all sitting ducks."

The gap between "We're all sitting ducks" and "We do not face a crisis" is the gap between halfhearted action and the all-out effort that might make a difference. It's the gap between changing light bulbs and changing the system that's powering our destruction.

In a rational world, no one would need to march. In a rational world, policymakers would have heeded scientists when they first sounded the alarm 25 years ago. But in this world, reason, having won the argument, has so far lost the fight. The fossil-fuel industry, by virtue of being perhaps the richest enterprise in human history, has been able to delay effective action, almost to the point where it's too late.

So in this case taking to the streets is very much necessary. It's not all that's necessary – a sprawling fossil-fuel resistance works on a hundred fronts around the world, from putting up solar panels to forcing colleges to divest their oil stocks to electioneering for truly green candidates. And it's true that marching doesn't always work: At the onset of the war in Iraq, millions marched, to no immediate avail. But there are moments when it's been essential. This is how the Vietnam War was ended, and segregation too – or consider the nuclear-freeze campaign of the early 1980s, when half a million people gathered in New York's Central Park. The rally, and all the campaigning that led to it, set the mood for a planet – even, amazingly, in the Reagan era. By mid-decade, the conservative icon was proposing to Mikhail Gorbachev that they abolish nuclear weapons altogether.

The point is, sometimes you can grab the zeitgeist by the scruff of the neck and shake it a little. At the moment, the overwhelming sense around the world is nothing will happen in time. That's on the verge of becoming a self-fulfilling prophecy – indeed, as I've written in these pages, it's very clear that the fossil-fuel industry has five times as much carbon in its reserves as it would take to break the planet. On current trajectories, the industry will burn it, and governments will make only small whimpering noises about changing the speed at which it happens. A loud movement – one that gives our "leaders" permission to actually lead, and then scares them into doing so – is the only hope of upending that prophecy.

A loud movement is, of necessity, a big movement – and this fossil-fuel resistance draws from every corner of our society. It finds powerful leadership from the environmental-justice community, the poor people, often in communities of color, who have suffered most directly under the reign of fossil fuel. In this country they're survivors of Sandy and Katrina and the BP spill; they're the people whose kids troop off to kindergarten clutching asthma inhalers because they live next to oil refineries, and the people whose reservations become resource colonies. Overseas, they're the ones whose countries are simply disappearing.

Sometimes in the past, trade unionists have fought against environmentalists – but unions in health care, mass transit, higher education, domestic work and building services are all beginning to organize for September, fully aware that there are no jobs on a dead planet. Energy-sector unions see the jobs potential in massive solar installation and a "just transition" off fossil fuels. Here's a banner I know you'll see in the streets of New York: CLIMATE/JOBS. TWO CRISES, ONE SOLUTION.

There will be clergy and laypeople from synagogues and churches and mosques, now rising in record numbers to say, "If the Bible means anything, it means that we need to care for the world God gave us." And there will, of course, be scientists, saying, "What exactly don't you understand about what we've been telling you for a quarter-century?"

And students will arrive from around the country, because who knows better how to cope with long bus rides and sleeping on floors – and who knows better that their very futures are at stake? They're near the front of this battle right now, getting arrested at Harvard and at Washington University as they fight for fossil-fuel divestment, and shaking up the establishment enough that Stanford, with its $18.7 billion endowment, just agreed to get rid of its coal stocks. Don't worry about "kids today." Kids today know how to organize at least as well as kids in the Sixties.

And then there will be those of us plain old middle-class Americans who may still benefit from our lives of cheap fossil fuel, but who just can't stand to watch the world drift into chaos. We look around and see that the price of solar panels has fallen 90 percent in a few decades; we understand that it won't be easy to shift our economy off coal and gas and oil, but we know that it will be easier than coping with temperatures that no human has ever seen. We may have different proposed solutions – carbon taxes! tidal power! – but we know that none of them will happen unless we open up some space. That's our job: opening up space for change on the scale that physics requires. No more fine words, no more nifty websites. Hard deeds. Now. More

 

© 2014

Climate Change Will Force Us to Abandon Coastal Cities

On Monday, the New York Times reported on two new climate change studies that came to the same, terrifying conclusion: “The heat-trapping gases could destabilize other parts of Antarctica as well as the Greenland ice sheet, potentially causing enough sea-level rise that many of the world’s coastal cities would eventually have to be abandoned.”

Abandoned.

While actual abandonment would not happen for many years (we’re talking centuries), the studies warned that our actions now are irrevocable and will lock in these future sea level rises. In other words, our descendants will be dealing with irreversible damage that we are committing today.

So, fast forward a few centuries from now, what will the world look like? What will the United States look like? Will people still live in Miami? Boston? New York? We don’t know what technology we will have then and we aren’t able to predict the pattern of storms. We do know that sea levels are rising and will threaten cities along the coasts of the United States.

“Barring some extraordinary advances in technology that we currently do not foresee,” Robert Hartwig, the president of the Insurance Information Institute, said, “you are left with the options of retreating from coastal areas not only in the United States, but around the world, or building fortifications against rising sea levels that would make the projects that we now see in places like the Netherlands look like child’s play.”

The Dutch government has set aside one billion euros a year through 2100 to strengthen dunes and dams throughout the country. Due to its low-lying position, the Netherlands is one of the most at-risk countries and has already crafted a long-term strategy to ensure the country’s survival. But in the United States, where one of our two main political parties remains skeptical about man-made climate change, such planning is unlikely to happen.

“If you have a plan and vision to stay there it is more likely to occur,” Robert Nicholls, a professor of coastal engineering at the University of Southampton, wrote in an email. “But USA does not have a planning culture.”

Planning will not come cheap. The mitigation techniques needed to fortify a city like Miami will cost billions of dollars, if not more. State and local governments will undoubtedly turn to the federal government for help, but that will be a political nightmare. Americans from non-coastal regions will likely object to paying for the restoration and fortification of coastal cities that are no longer naturally fit for habitation.

“Ultimately, reality will set in in the United States too, despite it being a relatively wealthy country,” Hartwig said. “Some areas will necessarily be abandoned or potentially become, in effect, islands. That’s another possibility. You say to yourself, do I abandon Miami or do I simply wall in a certain number of square miles of what is currently Miami and in effect create an island?

“Resources are always scarce and there are going to be many in the United States who think spending every available dime of every available tax dollar to save people from rising sea levels on the coast is a complete waste of money,” Hartwig added. “And they will have a point, because they’re paying tax dollars in Missouri or in North Dakota and they will not directly see a return on this investment.”

Global warming poses risks besides rising sea level. Severe storms may increase in frequency, although it’s difficult to predict how they will play out. Saltwater intrusion could imperil farm land up the Mississippi River. Droughts may become more common. Already now, scientists are wondering whether we’ve reached Peak Phosphorus—the point at which we reach the maximum global production rate of phosphorus, an essential fertilizer for crops.

Colin Green, a professor of water economics at Middlesex University, wrote in an email that he tells his students three things: “(1) they will not be able to retire until they are 75; (b) they will need to become vegetarians because we don't have enough water to support a high meat based diet; and (c) that when they go to the supermarket, they will need to take their urine with them which will be analysed and then they will be able to buy food with the same phosphorus content as the urine they bought in.”

The consequences of our inaction today will not be fixable down the road, no matter how much money the government spends. Instead, we will focus on containing the damage, whether through mitigation or abandonment. Insurance will be an important tool to allow the government to spread around some of that risk. But that assumes insurers don’t deem certain areas uninsurable—and that in turn depends on what we do today.

“I would say that if you look at the gradual sea level rise predicted over the next century, provided appropriate mitigation on the structures and in the communities in the higher cities are undertaken, then insurance is possible in these areas albeit at higher costs,” Hartwig said.

In some cases, the federal government may sell the insurance. For instance, right now, the feds offer subsidized flood insurance to homeowners in at-risk areas. When Congress passed the Biggert-Waters Act in 2012 to allow those rates to rise to their market level, they faced a swift backlash from homeowners who were going to see their insurance rates skyrocket. Led by congressmen from Gulf states, Congress gutted the bill in March. If that is any sign of what is to come, then policymakers are not prepared for the infinitely higher costs and tough choices they will face down the road. More

 

© 2014

Doomed Pine Island Glacier Releases Guam-Sized Iceberg into Southern Ocean

Science has confirmed it. Human-caused warming is killing Antarctica’s massive Pine Island Glacier (PIG). And this week’s release of a chunk of ice larger than Guam into the southern ocean is just one of the many major losses that will occur as part of what is now an inevitable demise of one of the world’s greatest glaciers.

The iceberg calved from Antarctica's Pine Island Glacier last November, according to NASA. The crack that produced it was first spotted in 2011. Since November, B31 has drifted out of Pine Island Bay and into the Amundsen Sea off the western side of the continent. 'The iceberg is now well out of Pine Island Bay and will soon join the more general flow in the Southern Ocean, which could be east or west in this region," iceberg researcher Grant Bigg from the University of Sheffield in England said in the NASA statement. Once that happens, the researchers worry it will be difficult track the iceberg during the long weeks of darkness that comprise the Antarctic winter. And don't expect it to melt. An iceberg of that size could hang around for a year or more, Robert Marsh, a scientist at the University of Southampton in England, said last year. The largest iceberg ever recorded was called B15. With an area of 4,250 square miles -- about the size of the state of Connecticut or the island of Jamaica - it calved off Antarctica's Ross Ice Shelf in March 2000. B15 has since broken up, but parts of it still exist around the Antarctic today.

Heat-Charged Blow to The Soft Underbelly of Antarctic Ice Shelves

As human greenhouse gas emissions caused the world’s oceans to warm, upwelling currents delivered a portion of that heat to the continental shelf zone surrounding Antarctica. A fortress of ice, numerous glacial ice shelves thrust out from this frozen land and drove deep into the sea floor. Ocean-fronting glaciers featured submerged sections hundreds of feet below the sea surface.

The warming currents encountered these massive ice faces, eroding their undersides and providing pathways for ocean waters to invade many miles beneath the glaciers. These invasions subjected the vulnerable ice shelves not only to the heat forcing of an ever-warming ocean, but also to wave and tidal stresses. The reduction in grounding and the constant variable stresses set the glaciers into a rapid seaward motion.

Antarctica’s most vulnerable glaciers lie along its western out-thrust. Two, Thwaites and the Pine Island Glacier, have recently seen very rapid increases in forward speed. Of these, the Pine Island Glacier, according to a recent study, is undergoing the process of an irreversible collapse. What this means is that the glacier’s speed of forward motion is now too great to be halted. Inevitably, even if the climate were to cool, the entire giant glacier will be launched into the world’s oceans where it will entirely melt out.

Guam-Sized Chunk of Ice to be One of Many

The Pine Island Glacier is massive, covering a total area of 68,000 square miles and, in some locations, rising to over 2,000 feet in height. It represents 10% of all the ice in the West Antarctic Ice Sheet, holding enough liquid water to raise sea levels by between 1 and 2.5 feet all on its own. And the now destabilized PIG is bound to put added stresses on the adjacent Thwaites glacier together with almost the entire West Antarctic ice system. Over recent years, PIG’s forward speed has accelerated. Increasing forward velocity by 73 percent from 1974 to 2007. Surveys made since that time show an even more rapid pace. By January of this year, studies were finding that PIG had entered a sate of irreversible collapse. So it is little wonder that enormous chunks of ice are breaking off from this massive glacier and drifting on out into the Southern Ocean.

As of early this week, the immense ice island dubbed B31 measuring 12×24 miles in size (nearly 290 square miles), slid off its temporary grounding on the sea bottom and began its journey out into the Southern Ocean. There it will remain for years, plaguing the world’s shipping lanes as it slowly disintegrates into a flotilla of icebergs. It is just the most recent event in the now ongoing decline of PIG. And we can expect many, many more major ice releases as this vast Antarctic glacier continues its dive to the sea. More

© 2014

Global Climate Will Cause Abrupt World Changes

If nations ignore the imminent problem of the increasing global climate, it will cause the world to endure abrupt changes that one single country is not prepared to handle.

Food and water supplies will be interrupted, the economy will diminish, millions of people will be displaced and civil unrest and violence will be triggered. The changing climate is causing permanent damage to ecosystems across the world, such as the loosening melt of Greenland, parching of the Amazon rainforest and melting of the Himalayan ice. Climate observations from around the world could prove to the naysayers that global warming is more than just a scientific theory. Many people of industrialized nations have a flat-earth view of the global climate change situation, which they think is an overreaction of tree huggers claiming the earth is warming up due to human abuse of the planet.

The Intergovernmental Panel on Climate Change (IPCC) composed a 29-page draft that summarizes various ways to prepare for increasing temperatures, scorching heatwaves, floods and heightened sea levels. The 29-page draft evaluates food and water shortages, extinction of animal and plant life and projects crop yield to remain the same or decline in range of up to two percent a year. More than a 100 governments and scientists will convene in Japan on March 25-29 to modify and approve the report. It will direct policies for the upcoming 2015 UN summit that is taking place in Paris, to circumvent greenhouse gas emissions. Almost 200 governments have agreed to reduce emissions from burning fossil fuels. The report outlines options for more efficient planning for catastrophes; like floods, hurricanes, efforts to cultivate drought and/or flood resistant crops and implementing practices conducive to water and energy conservation.

Another report released by several U.S. organizations, including the Environmental Defense Fund, is arguing that it is hard to measure world abrupt changes caused by global climate change. The changes of nature can be determined more easily than economic impact. Computer models give a more accurate view at rising sea levels and temperature predictions than the effects of drought and floods. The loss of biodiversity is hard to calculate and famine, social chaos community displacement are caused by other factors rather than just climate change alone.

A lead scientist of the IPCC report has commented that global climate change is shifting from environmental research to real-world observations of extreme climate events and added the climate is much different from thirty or forty years ago. Such as the drought in California, which is experiencing one its driest winters ever.

The most at-risk area of the world are the coastal regions of Asia, especially those living in the cities. Experts claimed they could endure the worst effects of global warming than any other part of the world. Millions of homes can be destroyed by flood and rising sea levels and famine could wipe out a large portion of the population. Climate change in coastal Asian urban centers will break down economic and social infrastructure prompting for extreme poverty and sociopolitical conflict. The causes of the global climate are already destroying the planet, however government, businesses and individuals can slow down the process of climate warming to prevent abrupt world changes. More

 

© 2014

New NASA Study Warns Of Climate Change’s Pace

CAPE CANAVERAL (CBSMiami) – NASA jumped back into the discussion of global climate change Tuesday with a new study that showed Earth’s climate will experience roughly 20 percent more warming than estimates originally stated, despite a recent slowdown.

NASA said the new predictions were based on more detailed calculations of the sensitivity of Earth’s climate to factors like greenhouse gas emissions, which help warm the planet.

Global temperatures have risen at a rate of 0.22 degrees Fahrenheit per decade since 1951. But according to NASA, since 1998 the rate slowed to 0.09 per decade, despite an increase in some greenhouse gases like carbon dioxide.

Some studies have since suggested greenhouse gases may not impact Earth as much as previously thought. The Intergovernmental Panel on Climate Change agreed and slightly lowered the range of Earth’s potential warming.

The new research focused on what’s called Earth’s “transient climate response.” This measurement looks at how temperatures will change as carbon dioxide increases until the total amount of carbon dioxide has doubled.

Previous estimates put the transient climate response at anywhere from 1.8 degrees to 2.52 degrees Fahrenheit. According to NASA’s new study, the transient climate response is approximately 3.06 degrees and not likely to fall below 2.34 degrees Fahrenheit.

The study focused on looking at how aerosols from natural sources like volcanoes and wildfire combined with manufacturing activities, cars, and energy production interacted. NASA said depending on the make-up of the aerosols, some cause warming and some cause cooling.

According to the study, the Northern Hemisphere will likely see more of an impact from aerosols as most man-made aerosols are released from industrial zones north of the equator and most of Earth’s landmasses are in the Northern Hemisphere.

“I kept thinking, we know the Northern Hemisphere has a disproportionate effect, and some pollutants are unevenly distributed,” the study’s author, climatologist Drew Shindell said. “But we don’t take that into account. I wanted to quantify how much the location mattered.”

Shindell said that based on his calculations, industrialized countries must reduce greenhouse gas emissions at the higher end of proposed restrictions to avoid the most damaging consequences of climate change. More

 

© 2014

Want to cut Arctic warming in half? Curb emissions now, study says

Global warming is changing the Arctic so quickly that experts say we should expect an ice-free Arctic Ocean in the summer within just a few decades.

But a group of scientists says there is a way to spare the Arctic from more disastrous climate change. In a new paper, they say that reducing global carbon emissions now could cut Arctic warming nearly in half by century’s end.

Society already has released enough carbon dioxide into the Earth’s atmosphere that over the next few decades temperatures in the Arctic will continue to rise two to three times faster than in Earth’s middle latitudes, according to the study.

“Over the next 20 or 30 years, the fix is in,” said James Overland, an oceanographer at the National Oceanic and Atmospheric Administration and lead author of the scientific paper. “That means more access to drilling, shipping and resource exploration. But it's not very good news for polar bears or walruses that depend on the sea ice habitat.”

Starting mid-century, society’s decisions about how to address climate change could begin to kick in, Overland said.

If carbon emissions continue on their current trajectory, by century’s end temperatures across the Arctic could rise by 23.4 degrees in the late fall and 9 degrees in the late spring, according to the study, which used computer models to predict the effects of different greenhouse gas emissions scenarios.

But if civilization levels off its emissions by mid-century, Arctic-wide warming would be limited to 12.6 degrees in the late fall and 5.4 degrees in the late spring, according to the paper accepted for publication in the journal Earth’s Future.

The Arctic is hypersensitive to climate change and is seeing some of the earliest and most severe effects because of a vicious circle known as “Arctic amplification.”

As Arctic sea ice shrinks to record lows, it is reflecting less sunlight and leaving behind more heat-absorbing ocean water. Thawing permafrost is increasing heat storage on land and raising temperatures even higher.

Already, the average annual temperature in the Arctic is 3.6 degrees higher than it was between 1971 and 2000, double the rise in lower latitudes during the same period, according to the study.

Overland conducted the research with three other scientists from the University of Washington, the National Snow and Ice Data Center in Boulder, Colo., and the International Arctic Research Center at the University of Alaska Fairbanks.

The scientists wrote that their research “makes a strong case to begin mitigation activities for greenhouse gases,” adding that stabilizing carbon dioxide emissions by mid-century “is a plausible target if decisive actions are begun soon.” More

 

 

Heed the warnings in extreme weather – or risk losing Earth

The recent cold spell united red and blue states: not in their interpretation of the event, but in their affliction. Weather can hit our fragile societies much harder than we care to admit.

No single weather extreme can be unequivocally attributed to global warming. But physics can say something about the big picture before the small events that form the big picture have occurred; and it says that extreme weather is likely to intensify.

On Thursday, the Intergovernmental Panel on Climate Change officially released its latest assessment of the scientific basis of anthropogenic climate change, providing the huge body of science that support the much debated summary for policymakers agreed by the 194 governments some weeks earlier.

For the first time, future climate was not merely projected for the 21st century. About 20 climate models from around the world were used to look beyond the year 2100. They show that if greenhouse gas emissions continue to rise as they have done in the past, the Earth will warm by more than 10C and it won't stop there.

Yet this is not going to happen. Not because the physical models are wrong. They are built on fundamental laws of nature that we rely on in our every-day life, laws that were established more than a hundred years ago and that have been tested in countless laboratory experiments. For more than a decade, different models project practically the same temperature ranges for the same greenhouse gas emissions. So those who want to make the world believe that climate models are bad in projecting the temperature of our planet are wrong.

Still, a warming of our planet by 10C, as predicted by some models, is not going to happen – simply because the underlying assumption of these projections is that there will be an industry around that can produce further emissions of that magnitude. But climate change will interfere with our fragile economic supply chains through unanticipated weather extremes. Whether this might reduce our industrial emissions is hard to say.

Initially a perturbation of our economic flows is likely to increase emissions because the loss will need to be compensated. But it seems inevitable that there will be a limit. A limit beyond which we cannot clean up the mess quick enough before the next hurricane makes land fall. When this limit is reached emissions might decline – but not for the good of humanity.

When climate scientists started to investigate the impacts of climate change, they did what scientists have always done: we sought the hardest problems that we considered solvable and went for them. In the case of climate change this led us to investigate gradual changes in large scale climate variables such as globally averaged precipitation or the monthly mean temperature of a continent.

But weather extremes are much harder to predict and so we did not. Such an approach is actually very common in science. In physics for example, people invented the theory of relativity and quantum physics than solving the turbulence problem which affects our every-day life whenever we drive a car or ride a bike. The world of the atoms and that of the remote universe posed solvable problems compared to the small-scale chaos that develops behind every car and every airplane.

Climate change, however, does not allow for that kind of scientific luxury – focusing on outer space instead of local weather.

If unabated, climate change will simply come upon us. Just because we cannot compute the track of a hurricane does not mean that we will not have to face it. Events like this year’s heavy winter in the US, or typhoon Haiyan which destroyed parts of the Philippines a few months ago, show that it is the unanticipated extremes and their impact on our fragile infrastructure that we will have to worry about.

Such individual events might remain just as unpredictable in the future as they have been in the past, and they will continue to impact the global flow of goods, energy and information which connects economies across the planet and makes it one world. If Google’s headquarters in California were shut down by, say the lack of cooling during a heat wave, this would affect large and small business everywhere. If a severe storm was to hit the harbour of Hong Kong, the effects would not just be local. It would spread along the supply chains around the globe.

The temperature difference between the last ice age and our current warm period, which carried humankind into civilisation over the past 10,000 years, is less than 5C. This is about the amount of warming that we will have caused by the end of the century if we continue as we have done in the past. Only we are doing it about one hundred times faster than nature did while trying to keep a highly efficient global economic network running.

The 2011 floods in Thailand surprised insurance companies around the world, because they disrupted Japanese production of hard drives and other computer essentials and led to shortages in Europe and the US. In 2010, an Icelandic volcano spitting dust into the air led to flight cancellation for two weeks – and were enough to push Europe to the edge of an economic deadlock. Not only major airlines were reported to be in economic trouble, the entire transportation system in Europe was in turmoil , shaking all economic and political processes in the European Union.

Societies do not need to be brought to the verge of starvation to slide into crisis. The social unrests we have seen in New Orleans after hurricane Katrina or more recently in Greece as a result of the financial crisis suggest that also seemingly stable countries are vulnerable to abrupt perturbations.

It is the unanticipated impacts on fragile infrastructures and supply networks that constitute the largest threat of global warming. While climate change is often considered to be a problem for the global poor and for fragile ecosystems, the impact of extreme events on the global economic network will test the stability of America as much as that of Europe.

No one knows where the limits of our adaptive capacity are, but a path towards 10C of warming will likely challenge these limits. The wall we are speeding towards may be hidden in the fog, but not knowing where it is does not make it vanish. The warnings provided by weather impacts on our society are quite clear. We can either take them seriously and turn around or find out the hard way. More