Plane Search Raises Questions About Sea of Floating Junk

March 30, 2014 by  
Filed under Plastic

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HT malaysia map search plane ml 140328 16x9 608 Plane Search Raises Questions About Sea of Floating Junk

The search area for missing Malaysia Airlines Flight 370 has been shifted nearly 700 miles northeast, March 28, 2014. (Australian Maritime Safety Authority)

The search for debris from missing Malaysia Airlines flight 370 has not turned up any evidence of a crash, but it has trained the world’s gaze on thousands of pieces of junk floating on the ocean’s surface.

Much of that debris could be made up of plastics, old appliances or parts of homes that have washed away from fragile communities, and cargo containers from ships, according to ocean advocacy group One World One Ocean.

Check out some of the facts about what’s really floating in our oceans:

The Pacific Garbage Patches: The most heavily-researched and well-known example of plastic pollution in the ocean is the Great Pacific Garbage Patch, made up of some 3.5 million tons of plastic beverage bottles, grocery bags, and plastic goods that have been pushed together by water currents that circulate between the west coast of North America and the east coast of China and Russia.

The Five Ocean Gyres: Pollutions can easily get caught in one of the five “gyres” of the ocean: the northern and southern Atlantic gyres, the Indian Ocean gyre, and the northern and southern Pacific gyres. The term describes water that moves in a circular, rotational current over a vast space in the ocean, pulling in stray plastics as it moves until they collide and merge with one another.  Because these gyres are trafficked heavily by cargo ships, the garbage patches contain large objects that have gone overboard from ships, including entire cargo containers.

Indian Ocean’s Plastic Problem: Researchers only began focusing on plastic pollution in the Indian Ocean in recent years, and in 2010 discovered garbage patches much like the famous Pacific Garbage Patch, according to Coastal Cares, another clean ocean advocacy group.

Plastic Breaks Down: As the garbage floats into the gyres it is broken down by salt and UV rays and begins releasing chemical properties into the water that then enter the food system, according to the Scripps Institute at the University of California San Diego. The plastics also fall into smaller pieces that can make them difficult to clean up.

10883 out of 10885 scientific articles agree: Global warming is happening…

March 25, 2014 by  
Filed under Global Warming

As geochemist James Lawrence Powell continues to prove, the only people still debating whether or not climate change is “real,” and caused by human activity, are the ones who aren’t doing the actual research. In an update to his ongoing project of reviewing the literature on global warming, Powell went through every scientific study published in a peer-review journal during the calendar year 2013, finding 10,885 in total (more on his methodology here). Of those, a mere two rejected anthropogenic global warming. The consensus, as he defines it, looks like this:

Powell even had to expand that itty bitty slice of the consensus pie five times for us to make it out  – the actual doubt about climate change within the scientific community is even tinier.

Adding this new data to his previous findings, Powell estimates that the going rate for climate denial in scientific research is about 1 in 1,000. The outliers, he adds, “have had no discernible influence on science.” From this, he comes up with a theory of his own:

Very few of the most vocal global warming deniers, those who write op-eds and blogs and testify to congressional committees, have ever written a peer-reviewed article in which they say explicitly that anthropogenic global warming is false. Why? Because then they would have to provide the evidence and, evidently, they don’t have it.

What can we conclude?

1. There a mountain of scientific evidence in favor of anthropogenic global warming and no convincing evidence against it.

2. Those who deny anthropogenic global warming have no alternative theory to explain the observed rise in atmospheric CO2 and global temperature.

These two facts together mean that the so-called debate over global warming is an illusion, a hoax conjured up by a handful of apostate scientists and a misguided and sometimes colluding media, aided and abetted by funding from fossil fuel companies and right wing foundations.


UPDATE 3/26/2014 9:27 PM: The headline of this post has been corrected to reflect the correct number of articles referenced by Dr. Powell’s research. Powell also clarifies that many of those studies were authored by multiple scientists, so the complete number is actually higher. The headlines has been updated to reflect this as well.

On his methodology, Powell notes, he only verified that two out of the 10,885 articles he found concluded that anthropogenic global warming (AGW) is wrong: “It is a safe assumption that virtually all the other 10883 do not reject–that is, they accept–AGW but I can’t say for sure that each one of them does.”


MORE from James Powell:

25 years after Exxon Valdez, the full extent of harm is still being discovered

March 25, 2014 by  
Filed under Toxic Spills

I guess it was 15 years ago, pretty much on the dot, that a group of Twin Cities environmentalists came to see me at the Strib editorial board bearing a fruit jar of water, pebbles and —  they said — crude oil from the Exxon Valdez.

You couldn’t see the oil, exactly. But you sure could smell it.

The occasion was the 10th anniversary of the tanker’s catastrophic grounding and the news that March was dominated by coverage of the decade’ s massive cleanup efforts, with a focus on how much better things were all over Prince William Sound, generally speaking, although some problems persisted, etc., etc.

My visitors had come to make the counterpoint — underscored by the jar that sat uncapped and fragrant on the conference table — that the successes were all superficial. The real problems, they insisted, continued just below the tidied surfaces. Sometimes just inches below, where this particular sample had recently been gathered.

Being new to environmental subjects, and inclined by newspaper service toward a certain alertness for gimmicks, I silently wondered: How do I know this really came from Cordova? How, for that matter, do they?

Now we are at the 25th anniversary of what was then the largest oil spill in U.S. history, although it holds that rank no longer. Further experience has unburdened this journalist and many others of much skepticism about the persistent impacts and possibly permanent harm that flowed from the Valdez’s ruptured hull on March 24, 1989.

Oil persists everywhere

And the fruit-jar demonstration for reporters remains popular. From a National Public Radio feature about Cordova’s 25-year struggle to survive the loss of its fisheries, its economic base and very nearly, at times, its will to endure:

Dave Janka captains the Auklet, a 58-foot wooden boat he uses for private charters. Most of his clients are scientists studying the oil spill’s impact. Along the way, Janka has collected his own samples.

He opens a jar labeled “February 19, 2014.” Janka collected the dark black oily-water mixture from Eleanor Island in Prince William Sound, digging down about 6 inches beneath the rocky shoreline. It smells like your hand after pumping gas at a service station.

“Looks like oil, smells like oil. It’s oil,” Janka says. “If you or I, in our backyard or at our mom and pop gas station, had a fuel tank leak, we would be held to the point of bankruptcy to clean that up.”

Bankruptcy is a fate that has been visited on more than a few Cordova households and businesses afflicted by the disaster but not, of course, on the company responsible for their misery. Exxon Mobil is mostly off the hook, though continuing cleanup needs are such that, according to the Anchorage Daily News,

The federal and state governments are still weighing the science of the spill’s effects and deciding whether to seek more money from Exxon Mobil for cleaning up remaining oil.

If there is evidence the spill is causing unexpected, continuing damage, the company could be forced to pay up to $100 million on top of the $900 million civil settlement that Exxon paid in 1991. The case lives on in the courts.

For perspective and fairness, I will point out this billion bucks is only a portion of Exxon Mobil’s total outlays for cleanup, out-of-court settlements and various other fines and penalties, which add to well over $4 billion.

Also, that Exxon Mobil spokesmen say the company learned valuable lessons from the Valdez disaster (which may be true), and that “The sound is thriving environmentally and we’ve had a very solid, complete recovery” (which is sheer snake oil).

Some species recover, others don’t

Here’s a summary of pluses and minuses for some of the marquee species in Prince William Sound:

Pink salmon and sockeye salmon are considered to have recovered, as have black cod. Herring, however, remain in bad shape, and this is bad news for the commercial fishing sector that was Cordova’s economic mainstay, because the spring herring catch filled in between the other important seasons.

The herring problem is also bad news for the overall ecosystem of Prince William Sound, because herring were an important food source for birds, other fish, and killer whales. One group of orcas is struggling back toward stability, another is expected to go extinct.

Sea otters have struggled to hold on, their greatly diminished numbers bumping along with little change until fairly recently, and though the recent populations have shown both ups and downs, federal officials announced a few weeks ago that their numbers had reached pre-spill numbers for the first time in 25 years. Cross your fingers.

For scientists studying the Valdez’s impacts, writes Elizabeth Shogren, also at NPR, there have been major revelations below the surface, from endeavors she likens to an autopsy that takes a quarter-century to complete:

When the tanker leaked millions of gallons of the Alaskan coast, scientists predicted major environmental damage, but they expected those effects to be short lived. Instead, they’ve stretched out for many years.

What researchers learned as they puzzled through the reasons for the delayed recovery fundamentally changed the way scientists view oil spills. One of their most surprising discoveries was that long-lasting components of oil thought to be benign turned out to cause chronic damage to fish hearts when fish were exposed to tiny concentrations of the compounds as embryos. …

Scientists had traditionally believed that oil basically had to cover an animal or embryo to hurt it. But the evidence they saw in Alaska suggested it didn’t take much oil to do a lot of damage. And that damage could manifest in different ways.

For example, oil under rocks and in sediments contaminated clams that sea otters ate. It didn’t kill the otters outright: Wildlife biologist Dan Esler of the U.S. Geological Survey says it shortened otters’ lives and suppressed the population for 20 years.

Social costs of destruction

Many who have followed the Valdez story will remember the early human misery, including the divisions between residents who got payouts from Exxon Mobil and those who did not; the mysterious illnesses that seemed to be related to chemical exposure from the spilled oil or the dispersants used to break it up; the suicide of a Cordova mayor.

That suffering continues, too, in different forms and at different levels. An interesting piece at phys.org focused on research by the University of Colorado’s Liesel Ritchie, who has been part of a 24-year-long (and counting) longitudinal study of “serious community conflict and mental health issues” in Cordova.

“What has fostered so much stress and anxiety in the community as a whole is different science says different things,” she said. “For example, Exxon scientists say everything is fine, that the impacts were minimal to begin with and that they subsided very quickly. Then other scientists who are not being paid by Exxon have other findings. What we’re talking about here at that level then is contested science which tends to cause uncertainty and stress in populations that are receiving this information and not knowing entirely how to interpret that.”

Even with a smaller than expected settlement, Ritchie says the people of Cordova appear to be moving on and doing their best to revive their fishing economy. However, she says, they have a long way to go. Before the spill Cordova consistently ranked in the top 10 most profitable U.S. seafood ports. A quarter century later, it’s not even in the top 25.

The most recent data, she said, show the first decline in community stress levels since the spill.

As a result of the Valdez grounding, Congress finally required tankers operating in U.S. waters to be of double-hull design, and federal and state regulations on tanker traffic in Prince William Sound and some other places were tightened, especially in regard to emergency preparedness.

A good look at some significant gains and serious continuing deficits can be found in the Homer Tribune, which noted that whatever preparations are made, ” the best plans can be challenged by weather. A drill last fall proved that when spill response efforts were entirely thwarted by a storm.”

“They couldn’t respond at all,” said Lisa Matlock, the council’s outreach coordinator. “It was one of those real-world experiences. From doing those real-world drills, we get better planning put in place.”

While the regional citizens advisory council set up in Prince William Sound has helped protect that 15,000 square mile body of water, other areas of the state, such as the Aleutian Islands, the Arctic and even Cook Inlet, which has an advisory council, are significantly less protected, many say. In those regions, if a tanker runs aground, rescue equipment can be hours or days away, and limited to what is available regionally.

Not all people who live Outside would necessarily know that Cook Inlet’s shoreline includes Anchorage.

Broken faith in justice

As I read about Alaskans’ broken faith with Big Oil, government regulation and especially the American court system, I was struck particularly by this comment from Jim Kallander, a fisherman and former Cordova mayor who watched Exxon Mobil fight successfully to have its penalties reduced in a 19-year series of appeals that reached finally to victory before the U.S. Supreme Court.

“All my life, I’d been brought up to think that, you know, you get to the Supreme Court and everything is made right. People are made whole. Issues are corrected. And I’m still disappointed. I’ll never get over it.”

Also, by the comments of Rick Steiner, an Alaskan professor of marine conservation who has studied the spill’s impacts for 25 years and does his own version of the fruit-jar trick with a pocket-size jar of oily stones he carries around. From Al-Jazeera America:

“This is beach gravel from Eleanor Island,” Steiner said, pointing out to Prince William Sound. “It’s covered in oil from the Exxon Valdez, 25 years on, and I didn’t have to dig very deep to find it. I dug it up earlier this year.

… “We can do better at reducing the risk. But once oil has spilled, you cannot clean it up, you cannot restore an oil-injured ecosystem and you can’t adequately rebuild human communities that are unravelled by these big industrial disasters.

“Some of these injuries persist. And industry rhetoric aside, we know these disasters do cause long-term, permanent environmental damage. And that’s one of the take-home lessons from Exxon Valdez a quarter of a century later: Once it happens, it’s never over.”

I suppose Minnesotans reading about Cordova’s plight and the hobbled ecosystem of Prince William Sound can be glad once again that we’re not an oil-producing state.

But we have our share of pipelines, and our share of risk in their probable future expansion, and in the expansion of terminals in the port of Superior, just across the bay from Duluth, to handle the rising flow of Canadian tar-sands oil.

Then there are the copper-nickel mines proposed at the edge of the Boundary Waters, whose champions assure us that new technologies guarantee that mining can be done right, that state regulation can ensure the natural environment is protected, that regulators and courts would insist that any accidental damage is mitigated and the responsible parties brought to account, that some kind of bond or insurance or trust fund will pay for whatever could possibly go wrong for centuries into the future.

Surely we can trust those official assurances. Can’t we?

How Global Warming Is Dissolving Sea Life (And What We Can Do About It)

March 25, 2014 by  
Filed under Global Warming

How Global Warming Is Dissolving Sea Life (And What We Can Do About It)S

The last time Earth’s oceans were this acidic, a six mile-wide sulphur-rich space rock had just smashed into the Yucatan Peninsula, unleashing a deluge of acid rain that exterminated all sea life in the the top 400 meters of the water column. Now, some 65 million years after the Cretaceous extinction, human activity is threatening to similarly decimate the ocean’s ecosystem—this time, from the bottom up.

How the Oceans Went Out of Whack

Under natural conditions, carbon dioxide is continuously transferred between the ocean, atmosphere, and continents in a delicately balanced process known as the carbon cycle. CO2 is pulled from the atmosphere by photosynthetic plants, which form the base of both terrestrial and oceanic food webs. It’ then subsequently sequestered in sediment when those plants—as well as the animals that feed on them—die and decompose. It’s a nice trick and it helps keep us all breathing.

Simultaneously, a roughly equivalent amount of carbon enters the atmosphere due to air-sea gas exchanges, as well as the respiration of sedimentary microbes as they decompose dead organic matter. Along with the nitrogen and water cycles, this carbon cycle is one of the primary facilitators of life on Earth, constantly recycling the limited supply of carbon that forms the base of every organism alive today.

But since the dawn of the industrial revolution, human activity—specifically, burning coal to produce energy—has upended the balance of the carbon cycle. The concentration of CO2 in the atmosphere has jumped from 280 ppm prior to industrialization to nearly 400 ppm today. We’re pouring more CO2 into the atmosphere than the system can sequester. This excess of atmospheric greenhouse gas has not only resulted in global warming but wreaked havoc on the ocean’s chemistry as well.

How Global Warming Is Dissolving Sea Life (And What We Can Do About It)S

When carbon dioxide enters the ocean, it reacts with seawater to create carbonic acid. This acid in turn produces a secondary reaction, splitting into separate bicarbonate and hydronium ions, which lower the water’s pH level. The more CO2 present in the atmosphere, the more gets absorbed by the oceans, and the lower the water’s pH will become.

Current scientific estimates suggest that the oceans are absorbing roughly 25 percent of the CO2 we produce each year, with another 45 percent remaining trapped in the atmosphere, and the rest being absorbed by terrestrial plants. Between 1751 and 1994, the surface ocean pH has dropped from an estimated 8.25 to 8.14. That may not seem like much but remember pH is logarithmic, just like the Richter Scale, so a .11 decrease constitutes a 30 percent increase in acidity. And if acidification rates continue at their present pace, the pH of the world’s oceans could drop another .5 units—roughly triple the acidity they are right now—by 2100. This would be cataclysmic for sea life and humanity alike.

What This Means for Sea Life

How Global Warming Is Dissolving Sea Life (And What We Can Do About It)

While an added abundance of atmospheric C02 may be a boon to plant life, the resulting acidification it causes is seriously impairing the development of oceanic calcifying organisms—everything that lives in a calcium-based shell from the phytoplankton, zooplankton, and corals that form the base of the food web to mollusks and crustaceans like clams, oysters, crabs, and lobsters.

Normally, there’s a supersaturation of carbonate ions, which these animals process into aragonite for use in their shells. However, as the pH decreases, calcium carbonate becomes more soluble which reduces the concentration of available carbonate ions. And not only does this reduce the rate at which organisms can build their protective structures, it also increases the rate at which existing shells dissolve. They’re literally being melted away by increasingly corrosive seawater.

How Global Warming Is Dissolving Sea Life (And What We Can Do About It)S

And it’s not just shellfish that are at risk. Decreased pH levels have been linked to a number of other adverse effects—both direct and indirect—such as the CO2-induced acidification of body fluids, known as hypercapnia, the reduced metabolism in jumbo squid, slowed embryonic development in Atlantic longfin squid, the inability of juvenile clownfish (poor Nemo!) to hear and smell approaching predators, and the diminished echolocation capacity of dolphins and whales.

Nowhere, though, is the effect more clearly illustrated than in coral. Both tropical and deep sea coral species, whose calcium carbonate homes form reefs that support entire ecosystems—acting as both nurseries for a number of commercial fish stocks as well as habitat for countless other species—are showing slower rates of growth than in the past and are suffering from the effects of coral bleaching at unprecedented levels. In 2005, for example, nearly half of the coral around the Virgin Islands and Puerto Rico were lost in a single year to mass bleaching events.

How Global Warming Is Dissolving Sea Life (And What We Can Do About It)S

Image: Acropora

The loss of their coral homes only serves to amplify the pressure exerted on existing fish and crustacean populations from overfishing, habitat loss, pollution, and rising sea temperatures. It won’t be long before humanity is directly affected too.

What This Means for Humans

The ocean acts as the primary source of protein for over a billion people worldwide. The US commercial fishing industry exported more than $5.1 billion of fish products in 2012 alone while providing employment for more than a million Americans. We are the fifth-largest seafood producer behind China, Peru, India, and Indonesia—catching just 3.8 percent of the global total annually.

Ocean acidification threatens to topple this industry in the near term if steps are not taken to correct it. The populations of popular shellfish like lobsters, crab, scallops, shrimp, oysters, mussels, and clams are in danger of collapse as the concentration of carbonate ions continues to decline. What’s more, the increased water acidity is doing strange things to crab stocks.

How Global Warming Is Dissolving Sea Life (And What We Can Do About It)S

Image: Sasha Isachenko

Alaskan Red King Crabs—the centerpiece of the Alaskan crabbing industry, which fetched $92.5 million for just 14.8 million pounds in 2011—show a 100 percent increase in larval mortality (twice as many die) when raised in acidified water, though the less sought-after dungeness crabs, which live in the same areas as King Reds, are less unaffected by the pH change. Maryland Blue crabs, on the other hand, will grow three times their average size when raised in lower pH waters and become extremely aggressive predators. Still, should these populations collapse, the damage to the regional fishing industry—not to mention the prices at your supermarket—will take decades to repair.

What We Can Do About It?

Since ocean acidification (like global warming) is the result of human activity, it therefore can be mitigated by changing the way we interact with the environment.

One obvious answer is to simply reduce the amount of CO2 we’re discharging into the air, though that is far easier said than done. While the world’s governments continue t0 work towards a political solution (see: the Kyoto Protocol) and coastal fisheries simultaneously strive to both slow the rate of acidification and adapt to changing water chemistry, there are a number of steps individuals can take to reduce their carbon footprint. And while reducing your personal carbon emissions may not make a very big impact, the actions of 6 billion individuals taken together could very well save the world. [PhysOrg – Wiki 1, 2, 3 – NOAA 1, 2, 3, 4NRDCWHOIEPASeattle TimesReal Science]

top image: Ethan Daniels

Global warming not stopped, will go on for centuries – WMO

March 24, 2014 by  
Filed under Global Warming

A tourist boat, decorated with green lights, travels on the Pearl River amid heavy haze in Guangzhou, Guangdong province March 3, 2014. REUTERS/Alex Lee

GENEVA (Reuters) – There has been no reverse in the trend of global warming and there is still consistent evidence for man-made climate change, the head of the U.N. World Meteorological Organisation (WMO) said on Monday.

A slow-down in the average pace of warming at the planet’s surface this century has been cited by “climate sceptics” as evidence that climate change is not happening at the potentially catastrophic rate predicted by a U.N. panel of scientists.

But U.N. weather agency chief Michel Jarraud said ocean temperatures, in particular, were rising fast, and extreme weather events, forecast by climate scientists, showed climate change was inevitable for the coming centuries.

“There is no standstill in global warming,” Jarraud said as he presented the WMO’s annual review of the world’s climate which concluded that 2013 tied with 2007 as the sixth hottest year since 1850 when recording of annual figures began.

“The warming of our oceans has accelerated, and at lower depths. More than 90 percent of the excess energy trapped by greenhouse gases is stored in the oceans.

“Levels of these greenhouse gases are at a record, meaning that our atmosphere and oceans will continue to warm for centuries to come. The laws of physics are non-negotiable,” Jarraud told a news conference.

The 21-page survey said the global land and sea surface temperature in 2013 was 14.5 degrees Celsius (58.1 Fahrenheit), or 0.50C (0.90F) above the 1961-90 average. It was also 0.03C (0.05F) up on the average for 2001-2010.

The WMO’s Annual Statement on the Status of the Climate, pointed to droughts, heatwaves, rising seas, floods and tropical cyclones around the globe last year as evidence of what the future might hold.

FLUCTUATIONS

It was issued on the eve of a conference bringing climate scientists together with officials from over 100 governments in Japan from March 25-29 to approve a report on the effects of future global warming and how these might be mitigated.

A draft of this report, from the Intergovernmental Panel on Climate Change (IPCC), says global warming will disrupt food supplies, slow world economic growth and may already be causing irreversible damage to nature.

The chair of the IPCC, Rajendra Pachauri, told Reuters last week that the report made even more compelling the scientific arguments for a reduction in greenhouse gas emissions.

Some 200 countries have agreed to try to limit global warming to less than 2.0 degrees Celsius above pre-industrial times, largely by cutting emissions from burning fossil fuels like coal, oil and gas.

Sceptics argue that changes in global weather are the product of natural fluctuations or other natural causes.

But such arguments were rejected by Jarraud.

Natural phenomena like volcanoes or the El Nino/La Nina weather patterns originating in Pacific Ocean temperature changes had always framed the planet’s climate, affecting heat levels and disasters like drought and floods, he said.

“But many of the extreme events of 2013 were consistent with what we would expect as a result of human-induced climate change,” declared the WMO chief, pointing to the destruction wreaked by Typhoon Haiyan in the Philippines.

Another example was the record hot summer of 2012-13 in Australia which brought huge bush fires and destruction of property. Computer simulations showed the heat wave was 5 times as likely under human influence on climate, Jarraud said.

Among other extreme events of 2013 probably due to climate change were winter freezes in the U.S. south-east and Europe, heavy rains and floods in north-east China and eastern Russia, snow across the Middle East and drought in south-east Africa.

(Editing by Robin Pomeroy)

Yes, Manmade Global Warming Is Worsening California’s Epic Drought

March 23, 2014 by  
Filed under Global Warming

By Joe Romm on
March 23, 2014 at 1:29 pm

California’s epic drought got even worse last week. The U.S. Drought Monitor reports that the area of California under moderate drought (or worse) rose from 94.6 percent of the state to a stunning 99.8 percent. The area under extreme or exceptional drought rose from 65.9 to 71.8 percent, encompassing the entire agriculture-rich Central Valley

Back in January, we interviewed 8 of the leading climate and drought experts in the country, who explained in great detail how climate change is worsening California’s epic drought in multiple ways. As I discussed in my 2011 literature review in the journal Nature — even in regions where climate change does not alter the amount of precipitation, it will have these effects:

What precipitation there is will probably come in extreme deluges, resulting in runoff rather than drought alleviation. Warming causes greater evaporation and, once the ground is dry, the Sun’s energy goes into baking the soil, leading to a further increase in air temperature…. Finally, many regions are expected to see earlier snowmelt, so less water will be stored on mountain tops for the summer dry season.

The president’s science advisor John Holdren made precisely the same points in a recent paper.

These points are disputed by very few. So why is there any confusion? A relatively small subset of experts are focused very narrowly on the issue of whether global warming caused a reduction in precipitation — but they generally fail to make clear how narrow their perspective is. NOAA’s Martin Hoerling did this in a recent New York Times piece, asserting “At present, the scientific evidence does not support an argument that the drought there is appreciably linked to human-induced climate change.”

Now, in fact, there is science supporting the argument that the reduction in precipitation is directly linked to human-induced climate change, specifically Arctic ice loss. I broke that story last June (see here) and updated it again in March.

But even setting aside the precipitation issue, our leading scientists have repeatedly made clear that global warming is worsening the drought. In a letter to the NY Times, three top drought experts — Peter Gleick, Jonathan Overpeck, and Connie Woodhouse — explain that the issue of what “caused” the drought “is the wrong question to ask”:

The current drought has certainly been exacerbated by climate change for one simple reason: Temperatures in California are now higher today, as they are globally. This alone increases water demand by crops and ecosystems, accelerates snowpack loss, and worsens evaporation from reservoirs. There are other complicating effects, but the influence of higher temperatures on drought is already real and cannot be ignored.

We are now unambiguously altering the climate, threatening water supplies for human and natural systems. This is but one example of how even today we are paying the cost of unavoidable climate changes.

As if to underscore this point, last week NOAA released its climate analysis of the U.S. winter, reporting:

California had its warmest winter on record…. The California winter temperature was 48.0°F, 4.4°F above the 20th century average, far exceeding the previous record, set in 1980/81, by 0.8°F.

And as Tamino explains, in California, “If we look at an actual measure of drought — the Palmer Drought Severity Index, or PDSI — then there is a decreasing trend (which means, toward more and/or more extreme drought) which is statistically significant.”

Finally, our favorite climate videographer Peter Sinclair has interviewed a variety of scientists on this subject in yet another must-see video:

Last edge of Greenland ice sheet to resist global warming is now unstable

March 17, 2014 by  
Filed under Global Warming

The last edge of the Greenland ice sheet that had resisted global warming has now become unstable, adding billions of tonnes of meltwater to rising seas, scientists said.

In a study published on Sunday in the journal Nature Climate Change, they said a surge in temperature from 2003 had eased the brakes on a long “river” of ice that flows to the coast in northeastern Greenland. Known as an ice stream, the “river” takes ice from a vast basin and slowly shifts it to the sea.

In the past, the flow from this ice stream had been constrained by massive buildups of ice debris choking its mouth. But a three-year spell of exceptionally high temperatures removed this blockage – and like a cork removed from a bottle helped accelerate the flow, the study said.

The stream, called Zachariae, is the largest drain from an ice basin that covers 16 per cent of the Greenland ice sheet.

From 2003 to 2012, northeastern Greenland disgorged 10 billion tonnes of ice annually into the ocean, the study found.

“Northeast Greenland is very cold. It used to be considered the last stable part of the Greenland ice sheet,” said Michael Bevis, an earth sciences professor at Ohio State University who led the study. “This study shows that ice loss in the northeast is now accelerating. So, now it seems that all the margins of the Greenland ice sheet are unstable.”

Greenland is estimated to contribute 0.5mm to the 3.2 mm annual rise in global sea levels.

The study’s main tool was data from a network of 50 Global Positioning System (GPS) sensors along the Greenland coast.

They use earth’s natural elasticity as a stethoscope of the ice sheet. When the ice melts in massive quantities the land rebounds and the sensor positions change.

To get a wider picture, the GPS data was then overlaid with data from four satellites that measured ice thickness from space.

“The Greenland ice sheet has contributed more than any other ice mass to sea level rise over the last two decades and has the potential, if it were completely melted to raise global sea level by more than seven metres,” said Jonathan Bamber, a professor at Britain’s University of Bristol.

EarthTalk: Global warming and your health

March 14, 2014 by  
Filed under Global Warming

Dear EarthTalk: How is it that global warming could cause an increase in health problems and disease epidemics? Do we have any evidence that it is already happening? — Jim Merrill, Provo, Utah

Global warming isn’t just bad for the environment. There are several ways that it is expected to take a toll on human health. For starters, the extreme summer heat that is becoming more normal in a warming world can directly impact the health of billions of people.

“Extreme high air temperatures contribute directly to deaths from cardiovascular and respiratory disease, particularly among elderly people,” reported the World Health Organization. “In the heat wave of summer 2003 in Europe, for example, more than 70,000 excess deaths were recorded.”

WHO added that high temperatures also play a role in elevated levels of ozone and other air pollutants known to exacerbate respiratory and cardiovascular problems. And according to the nonprofit Union of Concerned Scientists, warmer temperatures and higher levels of atmospheric carbon dioxide can stimulate plants to grow faster, mature earlier and produce more potent allergens.

“Common allergens such as ragweed seem to respond particularly well to higher concentrations of carbon dioxide, as do pesky plants such as poison ivy,” the group reported. “Allergy-related diseases rank among the most common and chronic illnesses.”

Another way global warming is bad for our health is that it increases extreme weather events that can injure or kills large numbers of people. According to WHO, the number of weather-related natural disasters has more than tripled since the 1960s. Likewise, increasingly variable rainfall patterns combined with higher overall temperatures are leading to extended droughts around the world.

“By the 2090s, climate change is likely to widen the area affected by drought, double the frequency of extreme droughts and increase their average duration six-fold,” reported WHO. One result is likely to be a downturn in agricultural productivity along with a spike in malnutrition. Another is less access to safe drinking water, a trigger for poor sanitation and the spread of diarrheal diseases — not to mention resource wars.

Perhaps most worrying to public health experts, though, is the potential for global warming to cause a spike in so-called “vector-borne diseases” like schistosomiasis, West Nile virus, malaria and dengue fever.

“Insects previously stopped by cold winters are already moving to higher latitudes” toward the poles, UCS reported. Researchers predict that thanks to global warming an extra two billion people, mostly in developing countries, will be exposed to the dengue virus over the next half century.

A related fear is that thawing permafrost in polar regions could allow otherwise dormant age-old viruses to re-emerge. This year, French and Russian researchers discovered a 30,000 year old giant virus, previously unknown to science, in frozen soil in Russia’s most northerly region. While the virus, which researchers dubbed Pithovirus sibericum, is harmless to humans and animals, its discovery has served as a wake-up call to epidemiologists about the potential re-emergence of other viruses that could make many people sick. While some of these re-emergent viruses might also be new to science, others could be revitalized versions of ones we thought we had eradicated, such as smallpox.

Contacts: WHO, www.who.int; UCS, www.ucsusa.org.

EarthTalk is by Roddy Scheer and Doug Moss of E — The Environmental Magazine (www.emagazine.com). Send questions to earthtalk@emagazine.com.

SATANIC ‘HELL DIAMOND’ tells of sunless subterranean sea

March 13, 2014 by  
Filed under Secrets of the Ocean

For years scientists have theorised about the amount of water locked in the Earth’s infernally hot depths, frustrated at not being able to get at a sample. Now geologists claim to be closer to an answer – thanks to a single ugly diamond found in Brazil.

The $20 diamond that yielded the ringwoodite sample

The brownish gem – bought for about $20 but of inestimable scientific value – has given researchers the first ever terrestrial sample of a rare mineral known as ringwoodite – the highest pressure high-pressure polymorph of olivine currently known to exist.

Analysis of the tiny sample of ringwoodite within the glistening gem shows that it contains a significant amount of water – 1.5 per cent of its weight – hinting at huge volumes of water beneath the surface of the Earth.


“This sample really provides extremely strong confirmation that there are local wet spots deep in the Earth,” said Graham Pearson of the University of Alberta. “That particular zone in the Earth, the transition zone, might have as much water as all the world’s oceans put together.”

Olivine – a green magnesium iron silicate – has been predicted to exist in its high-pressure gemstone form, peridot in the transition zone. Ringwoodite, the highest pressure peridot, has previously been found in meteorites, but has never been discovered on Earth before because scientists can’t reach the planet’s core.

The Brazilian “diamond” was found on the surface in 2008 after being brought to the top by a volcanic rock known as kimberlite. When Pearson and his team bought the sample, they were actually looking for another mineral and stumbled on the ringwoodite by accident.

“It’s so small, this inclusion, it’s extremely difficult to find, never mind work on,” he said, “so it was a bit of a piece of luck, this discovery, as are many scientific discoveries.”

The tiny sample of mineral has confirmed around 50 years of theoretical work by geophysicists and seismologists trying to define the makeup of the interior of the Earth and in a way, proves both the dry and wet theories.

It shows that the transition zone is an oasis of water in what is otherwise a very dry deep core, containing a vast mass of water recycled from the surface. This water may be responsible for many of the tectonic and volcanic features that make the Earth such a unique planet.

“One of the reasons the Earth is such a dynamic planet is because of the presence of some water in its interior,” Pearson said. “Water changes everything about the way a planet works.”

The full study, “Hydrous mantle transition zone indicated by ringwoodite included within diamond”, was published in Nature. ®

Gemnote

The University of Minnesota has a reasonably informative page about olivine here.

Global Warming Slows Antarctica’s Coldest Currents

March 5, 2014 by  
Filed under Global Warming

A shift from briny to fresh in Antarctica’s ocean waters in recent decades could explain the shutdown of the Southern Ocean’s coldest, deepest currents, a new study finds.

The cold currents, called the Antarctic Bottom Water, are chilly, salty rivers that flow from the underwater edge of the Antarctic continent north toward the equator, keeping to the bottom of the seafloor. The currents carry oxygen, carbon and nutrients down to the deepest parts of the ocean. Previous studies have found this deep, dense water is disappearing, though researchers aren’t sure if the shrinkage is part of a long-term trend linked to global warming, or a natural cycle.

The new study suggests that Antarctica’s changing climate is to blame for the shrinking Antarctica Bottom Water. In the past 60 years, the ocean surface offshore Antarctica became less salty as a result of melting glaciers and more precipitation (both rain and snow), researchers reported Sunday (March 2) in the journal Nature Climate Change. This growing freshwater layer is the key link in a chain that prevents the cold-water currents from forming, the study finds.

“Deep ocean waters only mix directly to the surface in a few small regions of the global ocean, so this has effectively shut one of the main conduits for deep-ocean heat to escape,” said Casimir de Lavergne, an oceanographer at McGill University in Montreal.

Holey ice

The linchpins linking freshwater and cold currents are polynyas, or natural holes within sea ice. These persistent regions of open water form when upwellings of warm ocean water keep water temperatures above freezing, or when winds drive sea ice away from the coast.

Polynyas are one of the main sources of Antarctica Bottom Water. Polynyas act like natural refrigerators, letting frigid temperatures and cold winds chill seawater and send it sinking down to the ocean bottom. As the cold water sinks, warmer ocean water comes up to take its place, maintaining the polynya’s open water. [Album: Stunning Photos of Antarctic Ice]

But as Antarctica’s ocean surface water has freshened, fewer polynyas have appeared, the researchers found. That’s because the fresher water is less dense. Even if the water is very cold, it doesn’t sink as readily as saltier water, de Lavergne explained. The freshwater acts like a lid, shutting down the ocean circulation that sends cold water to the seafloor, and brings up warm water into the polynyas.

“What we suggest is, the change in salinity of the surface water makes them so light that even very strong cooling is not sufficient to make them dense enough to sink,” de Lavergne told Live Science. “Mixing them gets harder and harder.”

Trapped heat

In addition to warming and shrinking the Antarctic Bottom Water currents, the reduction in polynyas could be trapping extra heat in the Southern Ocean, de Lavergne said.

“If the warm waters aren’t able to release their heat to the atmosphere, then the heat is waiting in the deep ocean instead,” he said. “This could have slowed the rate of warming in the Southern Hemisphere.”

De Lavergne cautioned that the heat-storage effect is localized and not related to the so-called global warming “hiatus” — the recent slowdown in the rise of global surface temperatures.

“Our study is still a hypothesis,” he added. “We say that climate change is preventing convection from happening, but we do not know how frequent it was in the past, so that’s a big avenue for future research.”

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