TIME Science

Study: The Latest Victims of Climate Change Are Snail Shells

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Limacina helicina sea snail Alexander Semenov—Getty Images

Sea snail sea snail, by the sea shore

Climate change has claimed its latest victim: Limacina helicina, a planktonic, predatory sea snail that’s a member of the taxonomic group more commonly known as sea butterflies. (The name is derived from the wing-like lobes the tiny creatures use to get around.) In a study recently published in journal Proceedings of the Royal Society B, a group of scientists from the National Oceanic and Atmospheric Administration (NOAA) and Oregon State University have found that the Pacific Ocean’s decreasing pH—its acidifying, in other words—is dissolving L. helicina’s thin shells.

The researchers collected sea butterfly samples from 13 sites along the Pacific coast (between Washington and southern California), going over each with a scanning electron microscope. More than half of the shells (53%) from onshore individuals showed signs of “severe dissolution damage,” while 24% of offshore individuals suffered dissolution damage. The study’s principal investigator, Dr. Nina Bednaršek of NOAA, described the affected L. helicina shells as having a texture not unlike “cauliflower” or “sandpaper.”

According to the paper, there was a “strong positive correlation” between the proportion of sea butterflies with severe shell dissolution damage and “the percentage of undersaturated water” near the ocean’s surface. The researchers conclude “shell dissolution owing to [human-caused ocean acidification] has doubled in near shore habitats since pre-industrial conditions across this region and is on track to triple by 2050,” a truly grim prognostication. Moreover, the broader implications for ecosystem are unclear, as damaged shells make it harder for L. helicina to fight infections, stay buoyant, and protect themselves from predators.

 

 

TIME climate science

Scientists Sound the Alarm on Global Warming, But Americans Sleep In

Climate change impacts Arctic ice
Rapid loss of Arctic sea ice is one of many risks of unchecked climate change Photo by Joe Raedle/Getty Images

A new report from the country's preeminent scientific body warns of the danger of unchecked global warming

Gallup released the results of a new poll on Americans’ opinions about climate change earlier this month. For those concerned about global warming, the data was not promising. On one hand, about two-thirds of Americans believed that global warming is happening or will happen during their lifetime—which, incidentally, happens to be the correct answer. But only about 36% of Americans said they believe that global warming will pose a “serious threat to their way of life” during their lifetimes. Climate change is also very low on the priority list for most Americans—51% of those surveyed said they worry about climate change very little or not at all. And 42% of Americans said they believe the seriousness of global warming is “generally exaggerated” in the news.

This is just one survey, and there is no shortage of methodological problems with most opinion polls. But the results make a sobering backdrop to yet another new report from a scientific organization that practically screams about the imminent dangers of global warming. This one is from the American Association for the Advancement of Science (AAAS), the preeminent scientific organization in the U.S., and it focuses starkly on the risks posed by unchecked climate change—both the more modest dangers that scientists are virtually certain about, and the catastrophic threats that might not materialize, but which would wreck havoc on the planet if they do:

The evidence is overwhelming: levels of greenhouse gases in the atmosphere are rising. Temperatures are going up. Springs are arriving earlier. Ice sheets are melting. Sea level is rising. The patterns of rainfall and drought are changing. Heat waves are getting worse as is extreme precipitation. The oceans are acidifying. The science linking human activities to climate change is analogous to the science linking smoking to lung and cardiovascular diseases.

That last bit is important. It took decades to establish a firm scientific connection between smoking and cancer—and it was an effort that tobacco companies fought every inch of the way, using doubt-stoking tactics that would later be taken up by the fossil fuel industry as it tried to make the public skeptical about man-made climate change. No doctor can tell you exactly how much smoking increases your risk of cancer and cardiovascular disease. But the science is strong enough—and lung cancer is a scary enough danger—that smoking rates have fallen drastically over the past few decades, reaching an all-time low this year.

That’s what the AAAS is trying to do with this report—cement the connection between man-made climate change and environmental and social disaster, to the point where the public will support steps to reduce carbon emissions. “This project is to make clear to the public and to policymakers what we know,” said Alan Lensher, the head of the AAAS. “The earth is warming and human behavior is heavily responsible for it. We need to do something now.”

Of course, this message has been repeated over and over again in scores of similar scientific reports, all sounding the same warning notes. Later this month the Intergovernmental Panel on Climate Change (IPCC) will come out with the next chapter of its latest assessment on climate science—this time focusing on the expected impacts of global warming—and you can expect a similar message. But as Justin Gillis of the New York Times writes, one difference with the AAAS report is its lead author, Mario Molina, who was part of a group of researchers in the 1970s who found a connection between chlorofluorocarbons (CFCs) and ozone depletion:

At a Fort Lauderdale, Fla., conference in 1972, a California scientist namedF. Sherwood Rowland learned that [CFCs] were accumulating in the air. What, he wondered, would happen to them? He eventually put a young researcher in his laboratory, Dr. Molina, onto the question.

To their own shock, the team figured out that the chemicals would break down the ozone layer, a blanket of gas high above the ground that protects the world from devastating levels of ultraviolet radiation. As the scientific evidence of a risk accumulated, the public demanded action — and eventually got it, in the form of a treaty phasing out the compounds.

That’s what climate campaigners would like to see with global warming: The science is established, it shifts public opinion, which then drives policy change to solve the problem. But climate change is a far more complex problem than ozone depletion, and carbon is far more central to the global economy that CFCs ever were. (And as Roger Pielke Jr. pointed out in this 2012 piece for the Breakthrough Institute, the story of science and the ozone layer is a little more complicated than it seems—solid technological alternatives to CFCs were developed well before talk of a global ban gained steam.) It’s hard to see one more blue-ribbon report moving public opinion on climate change, even one that carries the imprimatur of the AAAS.

Which is no reason not to try. (Although it may help to review the large body of social science around climate change inaction.) If you write about global warming day in and day out like I do, it’s easy to become immured to all the warnings, all the dire predictions. But the reality is that we are very much in the early stages of what the scientist Ken Caldeira has called “the great climate experiment,” with the planet is projected to warm faster over the next century than it has in 65 million years. Right now the CO2 concentration in the planet’s atmosphere has passed 400 ppm—it was 280 ppm before we began mass burning fossil fuels in the 19th century—and it’s likely to stay that high for the rest of the month, and eventually, forever.

It’s possible that we may get lucky and escape the most catastrophic risks posed by climate change—just as it’s possible you can smoke a pack a day and live until 90. It’s just not likely, and every day that passes without any real effort to curb carbon emissions makes disaster more certain. Sooner or later.

TIME Volcanoes

Volcanoes May Be Slowing Down Climate Change

The planet hasn't been warming as much as early climate models once predicted, and some scientists believe it's because sulfur emissions from erupting volcanoes are blocking sunlight in some parts of the planet, cooling the Earth's overall temperature

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Small volcanic eruptions might be part of the reason why the pace of global warming hasn’t kept up with previous predictions, a new study published in Nature Geoscience suggests.

Eruptions of at least 17 volcanoes since 2000, including Kasatochi in Alaska and Merapi in Indonesia, seem to have had a cooling influence on the temperature of the Earth’s surface and lower atmosphere. In the past, researchers observed increases in levels of greenhouse gases and in global warming, but for the past 15 years the Earth’s surface temperatures have shown relatively little warming. This so-called ‘hiatus’ puzzled researchers around the globe have been working to understand this phenomenon. “The hiatus is a fascinating detective story,” says Benjamin Santer, the lead author of the study and an atmospheric scientist at the Lawrence Livermore National Laboratory. “What we show is that even without any computer model calculations there is a clear signal of these early volcanic activity having effects on temperatures and on the reflected sunlight of the atmosphere,” says Santer.

Research shows that large volcanic eruptions inject sulfur dioxide gas into the stratosphere. The gas forms tiny droplets of sulfuric acid, also known as “volcanic aerosols,” that can block sunlight. That cooling effect has been largely ignored by climate scientists until now, but it seems to partly offset the warming from human-caused changes in greenhouse gases.

But volcanoes are just one of the different factors that contributed to hiatus. Other causes include an unusually dormant solar cycle and an increase in Chinese emissions of sulfur dioxide, which seem to have the same cooling effect. Scientists also believe that some of the extra heat generated by the rise in greenhouse gases is being absorbed by the oceans. “The next scientific challenge is to figure out the degree of culpability of these factors,” says Santer. But unfortunately for us, the cooling effect is expected to be temporary—if we keep emitting greenhouse gases, the climate will keep warming.

 

TIME

Hundred Years of Dry: How California’s Drought Could Get Much, Much Worse

California faces historic drought
California is the driest it has been on record, but its geologic history indicates the drought could get far worse David McNew / Getty Images

Scientists fear California's long-ago era of mega-droughts could be back

As he gave his State of the State speech yesterday, California Gov. Jerry Brown had reason to feel pretty good. The 75-year-old governor has helped rescue the state from fiscal insolvency and presided over the addition of 1 million new jobs since 2010. But as he spoke, Brown hit a darker note. Last week, amid the driest year for the state since record-keeping began in the 1840s, Brown declared a drought emergency for California, and in his speech he warned of harder times ahead:

Among all our uncertainties, weather is one of the most basic. We can’t control it. We can only live with it, and now we have to live with a very serious drought of uncertain duration…We do not know how much our current problem derives from the build-up of heat-trapping gasses, but we can take this drought as a stark warning of things to come.

(MORE: Can GM Crops Bust the Drought?)

Californians need to be ready, because if some scientists are right, this drought could be worse than anything the state has experienced in centuries. B. Lynn Ingram, a paleoclimatologist at the University of California, Berkeley, has looked at rings of old trees in the state, which helps scientists gauge precipitation levels going back hundreds of years. (Wide tree rings indicate years of substantial growth and therefore healthy rainfall, while narrow rings indicate years of little growth and very dry weather.) She believes that California hasn’t been this dry since 1580, around the time the English privateer Sir Francis Drake first visited the state’s coast:

If you go back thousands of years, you see that droughts can go on for years if not decades, and there were some dry periods that lasted over a century, like during the Medieval period and the middle Holocene [the current geological epoch, which began about 11,000 years ago]. The 20th century was unusually mild here, in the sense that the droughts weren’t as severe as in the past. It was a wetter century, and a lot of our development has been based on that.

Ingram is referring to paleoclimatic evidence that California, and much of the American Southwest, has a history of mega-droughts that could last for decades and even centuries. Scientists like Richard Seager of Columbia University’s Lamont-Dohery Earth Observatory have used tree-ring data to show that the Plains and the Southwest experienced multi-decadal droughts between 800 A.D. and 1500 A.D. Today dead tree stumps—carbon-dated to the Medieval period—can be seen in river valley bottoms in the Sierra Nevada mountains, and underwater in places like California’s Mono Lake, signs that these bodies of water were once completely dry. Other researchers have looked at the remains of bison bones found in archaeological sites, and have deduced that a millennium ago, the bison were far less numerous than they were several centuries later, when they blanketed the Plains—another sign of how arid the West once was. The indigenous Anasazi people of the Southwest built great cliff cities that can still be seen in places like Mesa Verde—yet their civilization collapsed, quite possibly because they couldn’t endure the mega-droughts.

(MORE: How the Drought of 2012 Will Make Your Food More Expensive)

In fact, those droughts lasted so long that it might be better to say that the Medieval West had a different climate than it has had during most of American history, one that was fundamentally more arid. And there’s no reason to assume that drought as we know it is the aberration. Ingram notes that the late 1930s to early 1950s—a time when much of the great water infrastructure of the West was built, including the Hoover Dam—may turn out to have been unusually wet and mild on a geologic time scale:

I think there’s an assumption that we’ll go back to that, and that’s not necessarily the case. We might be heading into a drier period now. It’s hard for us to predict, but that’s a possibility, especially with global warming. When the climate’s warmer, it tends to be drier in the West. The storms tend to hit further into the Pacific Northwest, like they are this year, and we don’t experience as many storms in the winter season. We get only about seven a year, and it can take the deficit of just a few to create a drought.

These mega-droughts aren’t predictions. They’re history, albeit from a time well before California was the land of Hollywood and Silicon Valley. And the thought that California and the rest of the modern West might have developed during what could turn out to be an unusually wet period is sobering. In 1930, a year before construction began on the Hoover Dam, just 5.6 million people lived in California. Today more than 38.2 million live in the largest state in the U.S., all of whom need water. California’s 80,500 farms and ranches produced crops and livestock worth $44.7 billion in 2012, but dry farming districts like the Central and Imperial Valleys would wither without irrigation. (Altogether, agriculture uses around 80% of the stare’s developed water supply.) More people and more crops have their straws in California’s water supply. Even in normal years, the state would be in trouble. If we see a return to the bone-dry climate of the Medieval period, it’s hard to see how the state could survive as it is now. And that’s not even taking the effects of climate change into account—the most recent Intergovernmental Panel on Climate Change (IPCC) report found that it was likely that warming would lead to even drier conditions in the American Southwest.

In his speech, Brown told Californians “it is imperative that we do everything possible to mitigate the effects of the drought.” The good news is that the sheer amount of water we waste—in farms, in industry, even in our homes—means there’s plenty of room for conservation. The bad news is that if California lives up to its climatological history, there may not be much water left to conserve.

(MORE: Rising Temperatures and Drought Create Fears of a New Dust Bowl)

TIME climate science

Snowpocalypse or Not, 2013 Was One of the Warmest Years on Record

Winter Storm Climate Change
It may not feel like it to snowbound residents in New York, but the climate is still warming. TIMOTHY A. CLARY/AFP/Getty Images

Amid a polar winter in much of the U.S., a new report reinforces the long-term trend of global warming—and sets the stage for an even hotter 2014

As I write this, I can see snow falling heavier and heavier outside my office window in midtown Manhattan. Up to 14 inches (36 cm) are projected to accumulate by Wednesday morning, part of major winter storm that’s spreading from South Carolina to Maine. Temperatures are predicted to stay well below normal for the rest of the week, as we all remember what winter used to be like. In short, it’s going to be cold, snowy and brutal, and Americans might feel as if warm weather will never return.

But don’t worry—on a global climatic scale, the heat is still on. That’s the takeaway from the National Oceanic and Atmospheric Administration’s (NOAA) annual analysis of global climate data, which was released Tuesday. The red-hot numbers:

  • 2013 ties with 2003 as the fourth-warmest year globally since records began in 1880.
  • The annual global combined land and ocean surface temperatures was 58.12 degrees Fahrenheit (14.52 degrees Celsius), 1.12 degrees Fahrenheit above the 20th century average (the warmest year on record is 2010, which was 1.19 degrees Fahrenheit (0.66 Celsius) above the average.
  • 2013 was the 37th consecutive year that the annual global temperature was above the average, which means that if you were born any year after 1976, you’ve never experienced a year when the global climate was average, let along cooler.
  • Including 2013, 9 of the 10 warmest years on record have occurred in the 21st century, and just one year in the 20th century—1998—was warmer than 2013.

(MORE: Climate Change Might Just Be Driving the Historic Cold Snap)

The NOAA report, coming out in the middle of a major snowstorm and during a U.S. winter that’s been marked by the polar vortex, is a reminder that climate isn’t about the day-to-day changes in the weather (Note: NASA came out with its own report on 2013, using a different calculating method than NOAA, and found 2013 to be slightly cooler, but still the seventh-warmest year on record). It’s about the very long-term, as Gavin Schmidt, the deputy director of NASA’s Goddard Institute for Space Studies in New York, said on a conference call with reporters Tuesday afternoon:

The long-term trends in climate are extremely robust. There is year-to-year variability. There is season-to-season variability. There are times such as today when we can have snow even in a globally warmed world but the long-term trends are very clear. They’re not going to disappear.

Not only is climate change a long-term phenomenon, it’s also a global one, though it’s easy to get lost in our weather. Case in point: the average temperature in the continental U.S. in December was 30.9 F (-0.6 C). That’s 2.0 F (1.1 C) below the 20th century average. That’s the 21st coldest winter on record for the U.S. You weren’t just a wimp—December really was chilly for much of the U.S.

But the globally the picture was very different. The worldwide average temperature in December was 55.15 F (12.84 C), which is 1.15 F (0.64 C) above the 20th century average. While the U.S. was shivering, on a global scale December 2013 was the third warmest December on record. That’s global warming.

And 2014, despite the snowy and chilly start in the U.S., could be even hotter. Scientists now say that an El Nino seems likely to develop later this year, which is likely to push temperatures up in 2014 and 2015, since El Nino years tend to be warmer. So enjoy the snow while you can—it will likely be a faint memory by time Americans are sweating in July.

(MORE: Arctic Blast: The Northern Air Mass Bringing Record-Breaking Cold to the U.S.)

TIME climate science

U.S. Carbon Emissions Climb for the First Time in Three Years

Coal plants would see their carbon emissions regulated by the EPA Dennis MacDonald via Getty Images

As coal regains footing, U.S. carbon emissions are likely back on the rise

Energy related CO2 emissions in the United States are projected to have risen in 2013, the first growth in three years, due largely to an increase in the use of coal to produce electricity, according to data released by the U.S. Energy Information Administration (EIA).

The EIA expects carbon emissions from producing energy from coal, natural gas and petroleum to be around 2% higher in 2013 than 2012, as the use of coal—which had been falling thanks to cheaper natural gas and air pollution regulation—rebounds slightly from a low in April 2013.

Even with the increase, emissions in 2013 are still more than 10% lower than they were in 2005 due to the increasing use of natural gas, improving energy efficiency, the growth of zero-carbon renewables and a sluggish economy. The Obama administration has set a goal of achieving a 17% reduction in emissions by 2020 from 2005 levels as part of the effort to combat of climate change.

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Source: U.S. Energy Information Administration, Short-Term Energy Outlook, January 2014

TIME climate change

Why Some Mushrooms May Be Magic for Climate Change

Fungi growing in soil
EEM fungi like this Amanita mushroom help soils store more carbon Colin Averill

The soil contains more carbon than all living plants and the atmosphere combined. Now a new study says that a certain type of fungi can help soil hold up to 70% more carbon—with potentially big impacts for the climate

Fungi don’t get the respect they deserve. Maybe that’s because they do most of their work in the dark, beneath the ground or on dead matter, or because there’s something essentially alien and bacterial about their appearance and the way they grow. But fungi are so plentiful and basic to life that they’re recognized as their own phylogenic kingdom. There may be more than 5 million separate species of fungi, and the largest single organism on the planet is a fungus: the four sq. mi. (10 sq. km) Armillaria ostoya fungus, which lives in the soil of Oregon’s Blue Mountains and which may be more than 8,000 yeas old. Without fungi we wouldn’t have antibiotics, blue cheeses and most importantly, beer. And we won’t even get into the magic kind.

Fungi also play an important role in the carbon cycle, the biogeochemical process by which carbon—the essential element of life on Earth—moves between the air, soils and water. Plants sequester carbon dioxide, but when they die, that carbon enters the soil—a lot of it. Globally, soil is the biggest single terrestrial reservoir of carbon, far more than the amount of carbon contained in living things and in the atmosphere combined. (On a planetary scale, the oceans hold by far the most carbon.) As the dead plant matter is broken down by microbes in the oil, that carbon is released back into the air. The rate at which that carbon leaves the soil can obviously have a major impact on the amount of carbon in the atmosphere, which in turn helps drive climate change.

(MORE: Climate Change Might Just Be Driving the Historic Cold Snap)

One of the limits to the growth of those decomposing microbes is the availability of nitrogen in the soil. Living plants and soil microbes compete for nitrogen, and the less nitrogen is available to the microbes, the slower decomposition is—and the more carbon remains in the soil, instead of outgassing into the atmosphere. This is where the fungi come in. Most plants have a symbiotic relationship with mycorrhizal fungi: the fungi extract the nitrogen from the soil, and make it available to the plants through their roots. But according to a new study in Nature, one major type of the symbiotic fungi can extract nitrogen much more quickly than other types—and that in turn slows the growth of the competing microbes and leaves much more carbon locked away in the soil.

Researchers from the University of Texas, Boston University and the Smithsonian Tropical Research Institute ran computer models on data from more than 200 soil profiles from around the world. They found that soils dominated by ecto- and ericoid mycorrhizal (EEM) fungi contain as much as 70% more carbon than soils dominated by arbuscular mycorrhizal (AM) fungi. That’s because the EEM fungi produce more nitrogen-degrading enzymes, which allows them to extract more nitrogen from the soil. They essentially outcompete the soil microbes, which slows down their ability to decompose dead plant matter and return carbon from the soil to the atmosphere. “This analysis clearly establishes that the different types of symbiotic fungi that colonize plant roots exert major control on the global carbon cycle, which has not been fully appreciated or demonstrated until now,” said Colin Averill, a graduate student at the University of Texas and the lead author of the paper.

That relationship between the different types of fungi and plants is so important for the carbon cycle because it’s independent of temperature, precipitation, soil clay content and all the other variable factors that can influence plant growth and soil content. Perhaps unfortunately for us, though, AM fungi symbiosis is far more common, occurring in approximately 85% of plant families, while just a few plant families have a symbiotic relationship with EEM fungi. That could change as the composition of forests change, however, but we wouldn’t know the effects until scientists add the role of the different kinds of symbiotic fungi into global climate models, which they have yet to do.

“This study shows that trees and decomposers are really connected via these mycorrhizal fungi, and that you can’t accurately predict future carbon cycling without thinking about how these two groups interact,” said Averill. “We need to think of these systems holistically.” The humble fungus won’t be forgotten.

(MORE: A Newly Discovered Underground Lake in Greenland Will Help Us Understand Climate Change)

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