Greenland ice loss doubles from late 2000s

A new assessment from Europe’s CryoSat spacecraft shows Greenland to be losing about 375 cu km of ice year.

The team has produced elevation models for the ice sheets

Added to the discharges coming from Antarctica, it means Earth’s two big ice sheets are now dumping roughly 500 cu km of ice in the oceans annually.

“The contribution of both ice sheets together to sea level rise has doubled since 2009,” said Angelika Humbert from Germany’s Alfred Wegener Institute.

“To us, that’s an incredible number,” she told BBC News.

In its report to The Cryosphere journal, the AWI team does not actually calculate a sea-level rise equivalent number, but if this volume is considered to be all ice (a small part will be snow) then the contribution is likely to be on the order of just over a millimetre per year.

This is the latest study to use the precision altimetry data being gathered by the European Space Agency’s CryoSat platform.

The satellite was launched in 2010 with a sophisticated radar instrument specifically designed to measure the shape of the polar ice sheets.

The AWI group, led by senior researcher Veit Helm, has taken just over two years’ worth of data centred on 2012/2013 to build what are called digital elevation models (DEMs) of Greenland and Antarctica, and to asses their evolution.

These models incorporate a total of 14 million individual height measurements for Greenland and another 200 million for Antarctica.

When compared with similar data-sets assembled by the US space agency’s IceSat mission between 2003 and 2009, the scientists are able then to calculate changes in ice volume beyond just the CryoSat snapshot.

Negative shifts are the result of surface melting and ice discharge; positive trends are the consequence of precipitation - snowfall.

Greenland is experiencing the biggest reductions in elevation currently, losing about 375 cu km a year (plus or minus 24 cu km per year), with most of the action occurring at the west and south-east coast of the continent.

Significant thinning is seen also in the North East Greenland Ice Stream (NEGIS).

“This has three outlet glaciers and one of these, the Zachariae Isstrom, has retreated quite a bit and some volume loss has already been reported. But we see now that this volume loss is really propagating to upper areas, much further into the interior of the ice sheet than has been recorded before,” explained Prof Humbert.

In Antarctica, the annual volume loss is about 128 cu km per year (plus or minus 83 cu km per year).

As other studies have found, this is concentrated in the continent’s western sector, in the area of the Amundsen Sea Embayment.

Big glaciers here, such as Thwaites and Pine Island, are thinning and retreating at a rapid rate.

Some thickening is seen also, such as in Dronning Maud Land, where colossal snowfalls have been reported. But this accumulation does not offset the losses occurring in West Antarctica.

A British-led group recently reported its own Antarctica DEM, using a different algorithm to process the numbers in the CryoSat data.

The AWI outcomes look very similar, and the German team has transferred the exact same approach to Greenland so it can have confidence in comparing the two continents.

The losses also look consistent with the analysis coming out of the American Grace mission, which uses a different type of satellite to monitor gravity changes in the polar regions - to, in essence, weigh the amount of ice being dumped into the sea.

Prof Andy Shepherd, who was part of the British group that reported its findings in May, commented: “This is yet another exciting result from CryoSat, thanks to the team at AWI, charting yet more new ground by providing the first complete survey of ice volume changes in Greenland.

“However, the increased ice losses that have been detected are a worrying reminder that the polar ice sheets are still experiencing dramatic changes, and will inevitably raise concerns about future global sea-level rise.” More

 

© 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

This Ice Sheet Will Unleash a Global Superstorm Sandy That Never Ends

If you want to truly grasp the scale of Earth's polar ice sheets, you need some help from Isaac Newton. Newton taught us the universal law of gravitation, which states that all objects are attracted to one another in relation to their masses (and the distance between them).

The ice sheets covering Antarctica and Greenland are incredibly massive—Antarctica's ice is more than two miles thick in places and 5.4 million square miles in extent. These ice sheets are so large, in fact, that gravitational attraction pulls the surrounding ocean toward them. The sea level therefore rises upward at an angle as you approach an ice sheet, and slopes downward and away as you leave its presence.

This is not good news for humanity. As the ice sheets melt due to global warming, not only do they raise the sea level directly; they also exert a weaker gravitational pull on the surrounding ocean. So water sloshes back toward the continents, where we all live. "If Antarctica shrinks and puts that water in the ocean, the ocean raises around the world, but then Antarctica is pulling the ocean towards it less strongly," explains the celebrated Penn State University glaciologist Richard Alley on the latest installment of the Inquiring Minds podcast. "And as that extra water around Antarctica spreads around the world, we will get a little more sea level rise in the US than the global average."

Alley, a self-described "registered Republican" and host of the PBS program Earth: The Operators' Manual, spoke on the occasion of truly dire news, of the sort that ice sheet experts like him have been dreading for some time. Last week, welearned from two separate research teams that the ice sheet of West Antarctica, which comprises just one relatively small part of Antarctic ice overall but contains enough frozen water to raise global sea levels by some 10 or 11 feet, has been irrevocably destabilized. Scientists have long feared that of all the planet's great ice sheets, West Antarctica would be the first to go, because much of it is marine-based—the front edge of the ice sheet is bathing in increasingly warm water, which is melting it from beneath. Here's a helpful visualization of how this process works:

The great ice sheet naturally wants to push outward and spread into the sea, Alley explains, much like water spreads out when poured onto a flat surface. But the advance is held up by the "grounding line"—the ice sheet's mooring at a particular point on the sea floor.

And here's where the problem arises: The latest research suggests that the ice is melting from below, and thus, losing its moorings. The oceanfront glaciers of the West Antarctic Ice Sheet are experiencing "rapid grounding line retreat," in scientific parlance, and this is happening "sooner than we initially expected, scientifically," says Alley. The cause seems to be a change in winds driven by global warming, which in turn is sending more warm water toward Antarctica's glaciers. And as the glaciers lose ice from below, there is less friction with the ground, and thus faster ice flow into the sea, where it can contribute to sea level rise.

"What they found," Alley continues, "is that it's likely that the fuse has already been lit." 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

Coral Reefs Protect Shorelines By Reducing Wave Energy By 97 Percent, Study Finds

Coral reefs provide substantial protection against wave energy, lessening the impact of sea level rise and intense storm surges for 7 million people in the U.S. alone, according to a new report.

The report, published this week in the journal Nature Communications, reviewed 255 studies on the protective nature of coral reefs and found that reefs reduce wave energy by 97 percent on average, causing the waves that reach the shoreline to be significantly calmer than they would have been without the reefs. Michael Beck, one of the authors of the report and senior scientist for the Nature Conservancy, said he was surprised at the 97 percent average for reef wave reduction. He said he knew it would be a large number — other studies have shown that reefs are effective at reducing wave energy, but none yet had quantified it ocean-wide — but he didn’t know just how big.

The report also found that worldwide, 197 million people are protected by reefs, and that maintaining the health of coral reefs is far less expensive than installing artificial defenses — according to the report, the median cost of building artificial wave defenses is $19,791 per meter, while the median cost of coral restoration projects is $1,290 per meter. Beck said the Nature Conservancy is working in a coral reef in Grenville, Grenada to build back the reef’s crest, the highest part of the reef that’s the most important for wave-breaking. He said degredation of the reef crest, which has been caused over the last 50 years by climate change, pollution, and sand mining, can explain a “huge amount” of the erosion and sedimentation that’s been occurring in the bay.

“A variety of causes has led to a little bit of degradation in height in the reef, and when you’ve lost that height in the reef, you can suddenly explain a huge amount of problems that have been happening,” he said.

Beck’s team has been been building back the reef in Grenada by using old coral rubble and concrete blocks, then trying to regrow the living coral on those structures. Projects like that, he said, are important to coral reefs’ survival — though coral is threatened gravely by climate change and ocean acidification, he said reefs “can be resilient” and recover from stresses like bleaching. He pointed to a mass bleaching event that occurred in 1998, after El Niño drove up water temperatures worldwide, as evidence. Though many were worried the reefs wouldn’t bounce back from this event, which was the most extensive and severe in history, certain reefs did recover, despite significant losses worldwide.

“Those reefs that were managed well, where you reduce the other stressors like pollution and overfishing, recovered,” he said. “Living coral came back and came back in quite good abundances in places were coral reefs were managed well.”

That event points to the need for better reef management, Beck said, especially now, as reefs around the world continue to suffer the effects of warming oceans, pollution, fishing practices and other impacts. Elkhorn coral, which play an integral role in the reef ecosystem of the Florida Keys, are being killed off by White Pox disease, which one researcher says is likely caused by untreated human sewage that enters the ocean through leaky septic systems in Florida. And outside of the 1998 event, scientists have found other significant evidence of coral bleaching, an effect that’s due to warmer-than-usual ocean temperatures and is likely to get worse as the ocean warms.

Other coastal and marine ecosystems provide protection from storm surge, sea level rise and erosion, but they too are struggling with human-induced impacts — in fact, Beck said coral reefs are in better shape worldwide than oyster reefs and mangrove forests. These coastal ecosystems have also been found to be a cost-effective way of providing protection — an April report noted restoring ecosystems like oyster reefs can create more jobs than offshore oil development and provide $15 in net economic benefits for every $1 invested. More

 

© 2014

Climate change and the world’s coasts

Coastal regions may face massive increases in damages from storm surge flooding over the course of the 21st century.

According to a new study published in the Proceedings of the National Academy of Sciences, global average storm surge damages could increase from about 10-40 billion USD per year today to up to 100,000 billion USD per year by the end of century, if no adaptation action is taken. The study lead by the Berlin-based think-tank Global Climate Forum (GCF) presents, for the first time, comprehensive global simulation results on future storm surge damages to buildings and infrastructure. Drastic increases in these damages are expected, on one hand, due to rising sea-levels and, on the other hand, due to population and economic growth. Asia and Africa may be particularly hard hit because of their rapidly growing coastal mega-cities, such as Shanghai, Manila or Lagos.

“If we ignore this problem, the consequences will be dramatic,” explained Jochen Hinkel from GCF and the study’s lead author. In 2100, up to 600 million people (around 5 percent of the global population) could be affected by coastal flooding if no adaptation measures are put in place. “Countries need to take action and invest in coastal protection measures, such as building or raising dikes, amongst other options,” urged Hinkel. With such protection measures, the projected damages could be reduced to below 80 billion USD per year during the 21st century. The researchers found that investments level of 10 to 70 billion USD per year could achieve such a reduction.

Prompt action is needed most in Asia and Africa, where today large parts of the population are

already affected by storm surge flooding. Yet even Germany must invest in coastal protection. It is not only dikes that are needed however. Alternative and more flexible coastal protection measures that better fit the natural environmental should also be developed. Examples of such alternatives to dikes are the reintroduction of mangrove forests, the rehabilitation of coastal dunes or artificial oyster banks.

Meeting the challenge of adapting to rising sea-levels will not be easy. “Poor countries and heavily impacted small-island states are not able to make the necessary investments alone. They need international support,” explained Hinkel. Adding to the challenge, international finance mechanisms have thus far proved sluggish in mobilising funds for adapting to climate change, as the debate on adaptation funding at the recent climate conference in Warsaw once again confirmed.

“If we do not reduce greenhouse gases swiftly and substantially, some regions will have to seriously consider relocating significant numbers of people in the longer run,” explained Hinkel. Yet regardless of how much sea-level rise climate change brings, careful long-term regional and urban planning can ensure that development in high-risk flood zones is avoided. This long-term perspective is however a challenge to bring about, as coastal development tends to be dominated by short-term interests of, for example, real-estate and tourism companies, which prefer to build directly at the waterfront. More

 

Our Perpetual Ocean

This is an animation of ocean surface currents from June 2005 to December 2007 from NASA satellites. Watch how bigger currents like the Gulf Stream in the Atlantic Ocean and the Kuroshio in the Pacific carry warm waters across thousands of miles at speeds greater than four miles per hour (six kilometers per hour); how coastal currents like the Agulhas in the Southern Hemisphere move equatorial waters toward Earth's poles; and how thousands of other ocean currents are confined to particular regions and form slow-moving, circular pools called eddies. Credit: NASA/SVS
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The swirling flows of tens of thousands of ocean currents were captured in this scientific visualization created by NASA's Goddard Space Flight Center in Greenbelt, Md.

"There is also a 20-minute long tour, which shows these global surface currents in more detail," says Horace Mitchell, the lead of the visualization studio. "We also released a three-minute version on our NASA Visualization Explorer iPad app."

Both the 20-minute and 3-minute versions are available in high definition here: http://svs.gsfc.nasa.gov/goto?3827

The visualization covers the period June 2005 to December 2007 and is based on a synthesis of a numerical model with observational data, created by a NASA project called Estimating the Circulation and Climate of the Ocean, or ECCO for short. ECCO is a joint project between the Massachusetts Institute of Technology and NASA's Jet Propulsion Laboratory in Pasadena, Calif. ECCO uses advanced mathematical tools to combine observations with the MIT numerical ocean model to obtain realistic descriptions of how ocean circulation evolves over time.

These model-data syntheses are among the largest computations of their kind ever undertaken. They are made possible by high-end computing resources provided by NASA's Ames Research Center in Moffett Field, Calif.

ECCO model-data syntheses are being used to quantify the ocean's role in the global carbon cycle, to understand the recent evolution of the polar oceans, to monitor time-evolving heat, water, and chemical exchanges within and between different components of the Earth system, and for many other science applications.

In the particular model-data synthesis used for this visualization, only the larger, ocean basin-wide scales have been adjusted to fit observations. Smaller-scale ocean currents are free to evolve on their own according to the computer model's equations. Due to the limited resolution of this particular model, only the larger eddies are represented, and tend to look more 'perfect' than they are in real life. Despite these model limitations, the visualization offers a realistic study in both the order and the chaos of the circulating waters that populate Earth's ocean.

Data used by the ECCO project include: sea surface height from NASA's Topex/Poseidon, Jason-1, and Ocean Surface Topography Mission/Jason-2 satellite altimeters; gravity from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment mission; surface wind stress from NASA's QuikScat mission; sea surface temperature from the NASA/Japan Aerospace Exploration Agency Advanced Microwave Scanning Radiometer-EOS; sea ice concentration and velocity data from passive microwave radiometers; and temperature and salinity profiles from shipborne casts, moorings and the international Argo ocean observation system. More

 

Science team identifies tipping point in climate change: 2047

If you’ve been wondering when global warming will show up on your doorstep, Camilo Mora has an answer for you.

Dr. Mora, an associate professor at the University of Hawaii at Manoa, leads a team that has tackled the challenging question of when the climate will shift entirely beyond what could be considered natural.

Their result: The turning point arrives in 2047 as a worldwide average if fossil fuel consumption continues unabated; as late as 2069 if carbon emissions are curbed. Broken down by city the numbers are a bit more revealing. In Montreal, for example, the new normal will arrive a year sooner. For Toronto it’s 2049 and for Vancouver not until 2056. But the real spotlight of Dr. Mora’s study is what happens in the tropics, where profound changes could be entrenched within little more than a decade.

“By looking at timing we’ve come up with an entirely new set of implications on climate change,” Dr. Mora said.

Dr. Mora is not a climate scientist but an expert in dealing with huge amounts of data to pull out hidden information – a skill he honed over six years at Dalhousie University in Halifax, working with the likes of the late Ransom Myers. It was Dr. Myers’ number crunching skills that turned the plight of the world’s fish stock into headline news in 2003.

Ten years later, Dr. Mora is following in his mentor’s footsteps with a study that seems certain to grab attention.

“I want to let the numbers do the talking,” he said.

Climate scientists have long expressed high confidence that the planet is warming as a result of the heat trapping action of greenhouse gasses. The latest assessment from the UN’s Intergovernmental Panel on Climate Change puts that confidence at 95 per cent. Where scientists have been less confident is on the timing of the change. Different models show the global temperatures rising at different rates and the hundreds of scientists behind the IPCC assessment can’t say which model will turn out to be the best predictor of what actually happens over the course of this century.

Starting with an idea that came out of a course he was teaching last spring, Dr. Mora decided to address the gap with some nuts and bolts analysis.

His team combined data from all 39 currently available global climate models and went back nearly 150 years to see what the range of normal climate variability was over that time period.

“We looked at the minimum and maximum values that occurred in that 150-year window and that’s how we set our bounds of recent historical variability,” said Ryan Longman, a doctoral student who worked on the analysis, published Wednesday in the journal Nature.

Then the team tracked the combined predictions of the models forward at different points on the globe to watch how soon the predictions drifted completely out of their normal range. Once the coldest year at any given location was consistently warmer than the hottest year prior to 2005 the team considered the climate to have changed completely. The dates when this happens are different for different locations and they depend on the emissions scenario.

“I think this analysis is valuable and sheds new light on impacts,” said Jane Lubchenco, the former administrator of the U.S. National Oceanic and Atmospheric Administration in an e-mail.

Dr. Lubchenco, who was not involved in the study, stepped down earlier this year to return to academic research at Oregon State University. She said “no one has gone to the immense effort they did to really look critically at the data from so many places and over the entire period of time for which records are reliable.”

The key result of the finding, Dr. Mora said, is that tropical locations will leave the range of normal climate variability much sooner because they typically experience a narrow range of temperature and precipitation levels. That’s a worry Dr. Mora said, because species there are not well adapted to living outside those ranges. Similarly, cities and nations found along Earth’s equator are among the poorest and least equipped to deal with the health and environmental burden of climate change.

“Today when people talk about climate change the images that come to mind are melting ice and polar bears,” Dr. Mora said. “People might infer from this that the tropics will be less affected.”

Instead, he said, the new analysis showed that species and ecosystems in the tropics would soon be experiencing “unprecedented climate stress.” The trend also goes for marine ecosystems where the study shows that ocean acidification has already departed from the normal range with a disastrous outlook for coral reefs.

Ken Caldeira, an expert in global ecology at the Carnegie Institution in Stanford added that while the timing and global breakdown from Dr. Mora’s analysis represent solid science, what matters more is the response.

“Whether an ecosystem goes a decade or two earlier or later doesn’t really matter that much,” Dr. Caldeira said. “We must stop using the atmosphere as a waste dump for our greenhouse-gas pollution. Everything else is nuance.” More

 

ECLAC Launches Database on Climate Change Adaptation in Coastal Zones

2 October 2013: The UN Economic Commission for Latin America and the Caribbean (ECLAC) launched an interactive, web-based database aimed at helping Latin American and Caribbean (LAC) countries in planning coastal management and preventive measures to adapt to the effects of climate change on their coastal zones.

The database was launched on 2 October 2013 during the Tenth Annual Meeting of the Ibero-American Network of Climate Change Offices being held at ECLAC headquarters in Santiago, Chile.

The database was developed as part of a multi-year project, titled 'Effects of Climate Change on the Coast of Latin America and the Caribbean,' which is being implemented by ECLAC in cooperation with Spain's Ministry of Agriculture, Food and the Environment and the University of Cantabria. This project has produced several reports since 2012, examining the vulnerability of the LAC coastline to projected climate change impacts.

The database provides data on LAC coastal dynamics, climate variability, coastal vulnerability and exposure to climate change, current impact and a projection of predictable risks in the future. Outputs of projected impacts are geo-referenced, with details available for blocks of coastline 5 kilometers (km) wide and 30 km long. Among the variables taken into account by the database are annual sea level rise, changes in wave heights, shifts in wind direction, and erosion and changes in sediment dynamics. The database and associated tools are targeted to LAC planners and policymakers with the aim of improving territorial planning in coastal zones and estimated engineering requirements, as well as to put into place appropriate environmental impact procedures. [ECLAC Press Release] [IISD RS Story on ECLAC Report on LAC Coastal Vulnerability to Climate Change] [Publication: Database web viewer]

read more: http://larc.iisd.org/news/eclac-launches-database-on-climate-change-adaptation-in-coastal-zones/

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Threatened by rising seas, small island nations appeal for more aid at UN

25 September 2013 – On the front line of damage wrought by climate change, threatened with extinction from rising seas, leaders of some of the world’s small island States took to the podium at the United Nations General Assembly today to call urgently for greater international support to mitigate the perils.

Winston Baldwin Spencer, Prime Minister /
Minister for Foreign Affairs
Antigua and Barbuda

“Disastrously off course,” “profound disappointment” and “moral failure” were some of the terms used by heads of Small Island Developing States, known as SIDS, to depict their situation as the 68th General Assembly prepares to draw up long-term development plans for the decades after the end in 2015 of the current cycle of the anti-poverty Millennium Development Goals (MDGs).

“The corresponding actions to address the unique and special circumstances of SIDS by the international community has been lacking,” the Prime Minister of Antigua and Barbuda, Winston Baldwin Spencer, told the Assembly’s annual General Debate, summing up the almost two decades since the Barbados Programme of Action was adopted by at a UN conference on the sustainable development of SIDS in 1994.

“It is a recognized fact, but it is worth repeating that small island States contribute the least to the causes of climate change, yet we suffer the most from its effects. Small island States have expressed our profound disappointment at the lack of tangible action,” he said referring to efforts in UN climate change talks to protect SIDS and other vulnerable countries.

“Developed countries should shoulder their moral, ethical and historical responsibilities for emitting the levels of anthropogenic greenhouse gases into the atmosphere. It is those actions which have now put the planet in jeopardy and compromised the well-being of present and future generations,” the Caribbean leader stressed.

Noting uneven progress in achieving the MDGs, Prime Minister Kamla Persad-Bissessar of Trinidad and Tobago, who is also chairperson of Conference of Heady of State and Government of the Caribbean Community (CARICOM), warned that current approaches will not advance the MDG agenda by 2015 or ensure sustainable development in the post-2015 context.

Prime Minister Kamla Persad-Bissessar
of Trinidad and Tobago,

“SIDS have made significantly less progress in the area of development, than other vulnerable groups of countries. In some cases SIDS are on the frontlines of experiencing a reversal of many of the gains that have been achieved,” she said.

“Indeed in the preparations for our participation in that upcoming discourse (on the Post-2015 Development Agenda), the recognition of the vulnerabilities of small island developing States is one of the guidelines that CARICOM will apply when considering its commitments to the overall Agenda.”

From the other side of the planet, Kiribati President Anote Tong, stressing the “real and existential threat” his low-lying Pacific nation faces from rising seas, called for immediate international action to mitigate climate change and rising sea levels.

“We are disastrously off course. The scientists tell us that calamity awaits – and not just for those of us on low-lying islands,” he said. “What we are experiencing now on these low-lying atolls is an early warning of what will happen further down the line. No one will be spared. We cannot continue to abuse our planet in this way. For the future we want for our children and grandchildren, we need leadership.

“We need commitment. And we need action ....now,” he declared, noting that while Kiribati is taking adaptation measures to remain habitable for as long as possible, it is also looking to improve its people’s skills to a level where they can compete for jobs in the international labour market with dignity if the rising ocean forces them to migrate.

“All those countries with the ability to do so must contribute to the prevention of this calamity, or be forever judged by history.” More

 

Tool predicts sea-level rise on Pacific islands

HONOLULU (AP) - People concerned about how rising sea levels will affect communities in Hawaii, Guam and the Northern Marianas Islands have a new tool to help them plan ahead.

The National Oceanic and Atmospheric Administration and the University of Hawaii at Manoa worked together to incorporate these Pacific island areas into a national web-mapping tool that enables people to picture what rising sea levels will do to coastal areas.

The Sea Level Rise and Coastal Flooding Impacts Viewer overlays high-resolution aerial images on top of elevation data.

This allows users to see what higher sea levels would do to landmarks and critical infrastructure. It also shows what populations would be vulnerable to rising sea levels.

University of Hawaii Professor Chip Fletcher says it fills an important gap for Hawaii planners and managers. More

 

Jakarta will be underwater by 2030: National Council on Climate Change

The National Council on Climate Change (DNPI) predicts that half of Jakarta will be under water by 2030 due to global warming.

DNPI executive chairman Rachmat Witoelar said on Thursday that global warming could cause sea levels to increase significantly.

"If we allow this situation to continue, then by around 2030, half of Jakarta, specifically areas such as Ancol, will be under water," he said in Jakarta on Thursday, as quoted by Antara news agency.

Rachmat said that certain measures had to be taken in order to contain and anticipate the impacts of climate change.

He said big cities such as Jakarta contributed significantly to environmental damage, caused by garbage, air pollution from vehicles, tree-cutting activities and decline in open green spaces due to land conversion.

"Health Minister Nafsiah Mboi has asked people to become more aware of environmental problems and climate change because all these issues will negatively impact people's health," said Rachmat.

He added that people had to increase awareness on the need to protect themselves from the impact of global warming by keeping the environment green, maintaining cleanliness, and reducing air pollution.

Rachmat said that the government through the DNPI has continued to tackle the multiple impacts of climate change.

Recently, the DNPI launched a book titled "Climate Change and Challenges of the Nation's Civilization".

Rachmat said Indonesia has discussed efforts on how to improve the global environment, which was also related to the state of domestic environment.

"Indonesia ratified the United Nations Framework Convention on Climate Change (UNFCCC) on Aug.23, 1994. As an active UN member country, Indonesia has played an active role in tackling environment crisis," he said. More