“This upwelling is both a blessing and a curse,” Chan said. “The upwelling injects nutrients that make our ocean so productive. That’s why Steinbeck wrote ‘Cannery Row.’ We live in a very special ocean. But the curse is that this upwelling creates low oxygen and low pH. So we’re much closer to any tipping points that could push us past a threshold.”
Although the causes and effects of ocean acidification and low oxygen are global, the panel found hopeful news about the potential to deal with it locally.
Seagrass beds and kelp forests are more productive than tropical forests, capturing more carbon than other systems on the planet. By restoring marine vegetation, scientists hope to raise pH and oxygen levels in key areas.
Curbing marine pollution can also improve ocean chemistry, scientists said. Runoff from farms and lawns, such as nitrogen and phosphorus, feed algal blooms that dump carbon and deplete oxygen from local waters. Cutting back on those pollutants can “put off a potential evil hour when carbon dioxide are so high” that they cause irreparable damage to marine life, Dickson said.
Efforts to battle ocean acidification and low oxygen on the West Coast will be test cases for dealing with the problem elsewhere, scientists said
“The West Coast will be a harbinger for the types of ocean acidification impacts that will be widely felt across coastal North America in the coming decades,” the report states.
Despite the gloomy news, Chan said he’s hopeful that a solution is at hand, noting that bills pending in the California Legislature — Assembly Bill 2139 and Senate Bill 1363 — would study ocean acidity and promote eelgrass restoration.
“I’m leaving with an optimistic note, which I tend not to as a scientist, but I think the people who make decisions get it, and are ready to do something,” he said.
The new research was led by Robert E. Kopp, an earth scientist at Rutgers University who has won respect from his colleagues by bringing elaborate statistical techniques to bear on longstanding problems, like understanding the history of the global sea level.
Based on extensive geological evidence, scientists already knew that the sea level rose drastically at the end of the last ice age, by almost 400 feet, causing shorelines to retreat up to a hundred miles in places. They also knew that the sea level had basically stabilized, like the rest of the climate, over the past several thousand years, the period when human civilization arose.
But there were small variations of climate and sea level over that period, and the new paper is the most exhaustive attempt yet to clarify them.
The paper shows the ocean to be extremely sensitive to small fluctuations in the Earth’s temperature. The researchers found that when the average global temperature fell by a third of a degree Fahrenheit in the Middle Ages, for instance, the surface of the ocean dropped by about three inches in 400 years. When the climate warmed slightly, that trend reversed.
“Physics tells us that sea-level change and temperature change should go hand-in-hand,” Dr. Kopp said. “This new geological record confirms it.”
In the 19th century, as the Industrial Revolution took hold, the ocean began to rise briskly, climbing about eight inches since 1880. That sounds small, but it has caused extensive erosion worldwide, costing billions.
Due largely to human emissions, global temperatures have jumped about 1.8 degrees Fahrenheit since the 19th century. The sea is rising at what appears to be an accelerating pace, lately reaching a rate of about a foot per century.
One of the authors of the new paper, Dr. Rahmstorf, had previously published estimates suggesting the sea could rise as much as five or six feet by 2100. But with the improved calculations from the new paper, his latest upper estimate is three to four feet.
That means Dr. Rahmstorf’s forecast is now more consistent with calculations issued in 2013 by the Intergovernmental Panel on Climate Change, a United Nations body that periodically reviews and summarizes climate research. That body found that continued high emissions might produce a rise in the sea of 1.7 to 3.2 feet over the 21st century.
In an interview, Dr. Rahmstorf said the rise would eventually reach five feet and far more — the only question was how long it would take. Scientists say the recent climate agreement negotiated in Paris is not remotely ambitious enough to forestall a significant melting of Greenland and Antarctica, though if fully implemented, it may slow the pace somewhat.
“Ice simply melts faster when the temperatures get higher,” Dr. Rahmstorf said. “That’s just basic physics.”
A fisherman shovels grey sole, a type of flounder, out of the hold of a ship at the Portland Fish Pier in Maine, September 2015. New research finds the ability of fish populations to reproduce and replenish themselves is declining across the globe. The worst news comes from the North Atlantic, where most species are declining. (Gregory Rec/Portland Press Herald via Getty Images)
For anyone paying attention, it’s no secret there’s a lot of weird stuff going on in the oceans right now. We’ve got a monster El Niño looming in the Pacific. Ocean acidification is prompting handwringing among oyster lovers. Migrating fish populations have caused tensions between countries over fishing rights. And fishermen say they’re seeing unusual patterns in fish stocks they haven’t seen before.
Researchers now have more grim news to add to the mix. An analysis published Monday in the Proceedings of the National Academy of Sciences finds that the ability of fish populations to reproduce and replenish themselves is declining across the globe.
“This, as far as we know, is the first global-scale study that documents the actual productivity of fish stocks is in decline,” says lead author Gregory L. Britten, a doctoral student at the University of California, Irvine.
Britten and some fellow researchers looked at data from a global database of 262 commercial fish stocks in dozens of large marine ecosystems across the globe. They say they’ve identified a pattern of decline in juvenile fish (young fish that have not yet reached reproductive age) that is closely tied to a decline in the amount of phytoplankton, or microalgae, in the water.
“We think it is a lack of food availability for these small fish,” says Britten. “When fish are young, their primary food is phytoplankton and microscopic animals. If they don’t find food in a matter of days, they can die.”
The worst news comes from the North Atlantic, where the vast majority of species, including Atlantic cod, European and American plaice, and sole are declining. In this case, Britten says historically heavy fishing may also play a role. Large fish, able to produce the biggest, most robust eggs, are harvested from the water. At the same time, documented declines of phytoplankton made it much more difficult for those fish stocks to bounce back when they did reproduce, despite aggressive fishery management efforts, says Britten.
When the researchers looked at plankton and fish reproduction declines in individual ecosystems, the results varied. In the North Pacific — for example, the Gulf of Alaska — there were no significant declines. But in other regions of the world, like Australia and South America, it was clear that the lack of phytoplankton was the strongest driver in diminishing fish populations.
“When you averaged globally, there was a decline,” says Britten. “Decline in phytoplankton was a factor in all species. It was a consistent variable.”
And it’s directly linked to climate change: Change in ocean temperature affects the phytoplankton population, which is impacting fish stocks, he says.
Food sources for fish in their larval stage were also a focus of research published earlier this summer by Rebecca Asch, now a postdoctoral research associate at Princeton University. Asch studied data from 1951 to 2008 on 43 species of fish collected off the Southern California coast and found that many fish have changed the season when they spawn. When fish spawned too early or too late in the season, there can be less plankton available to them, shrinking their chance of survival. She calls it a “mismatch” between when the fish spawn and when seasonal plankton blooms.
Knowing just how vulnerable our fisheries are to potential climate change is on the radar of NOAA Fisheries. The agency has put together a Fish Stock Climate Vulnerability Assessment report expected to be released in early 2016. And like many things associated with climate change, there will be winners and losers.
Jon Hare is the oceanography branch chief for NOAA Fisheries’ Northeast Fisheries Science Center and a lead researcher on the agency’s assessment. He says they looked at 82 fish and invertebrate species in the Northeast. About half of the species, including Atlantic cod, were determined to be negatively impacted by climate change in the Northeast U.S. Approximately 20 percent of the species are likely to be positively impacted — like the Atlantic croaker. The remainder species were considered neutral.
Similar assessments are underway in the California Current and the Bering Sea, and eventually in all of the nation’s large marine ecosystems.
“This is where the idea of ecosystem-based management comes in. It’s not only fishing that is impacting these resources,” says Hare. “We need to take a more holistic view of these resources and include that in our management.”
Britten says the fact that productivity of a fishery can change should be an eye-opener for fisheries management.
“It’s no longer just pull back on fishing and watch the stock rebound. It’s also a question of monitoring and understanding the ability of stocks to rebound, and that’s what we demonstrated in this study. The rebound potential is affected as well,” says Britten.
Scientists demonstrate that a key organism in the ocean’s food web will start reproducing at high speed as carbon dioxide levels rise, with no way to stop when nutrients become scarce
Imagine being in a car with the gas pedal stuck to the floor, heading toward a cliff’s edge. Metaphorically speaking, that’s what climate change will do to the key group of ocean bacteria known as Trichodesmium, scientists have discovered.
Trichodesmium (called “Tricho” for short by researchers) is one of the few organisms in the ocean that can “fix” atmospheric nitrogen gas, making it available to other organisms. It is crucial because all life — from algae to whales — needs nitrogen to grow.
A new study from USC and the Massachusetts-based Woods Hole Oceanographic Institution (WHOI) shows that changing conditions due to climate change could send Tricho into overdrive with no way to stop — reproducing faster and generating lots more nitrogen. Without the ability to slow down, however, Tricho has the potential to gobble up all its available resources, which could trigger die-offs of the microorganism and the higher organisms that depend on it.
By breeding hundreds of generations of the bacteria over the course of nearly five years in high-carbon dioxide ocean conditions predicted for the year 2100, researchers found that increased ocean acidification evolved Tricho to work harder, producing 50 percent more nitrogen, and grow faster.
The problem is that these amped-up bacteria can’t turn it off even when they are placed in conditions with less carbon dioxide. Further, the adaptation can’t be reversed over time — something not seen before by evolutionary biologists, and worrisome to marine biologists, according to David Hutchins, lead author of the study.
“Losing the ability to regulate your growth rate is not a healthy thing,” said Hutchins, professor at the USC Dornsife College of Letters, Arts and Sciences. “The last thing you want is to be stuck with these high growth rates when there aren’t enough nutrients to go around. It’s a losing strategy in the struggle to survive.”
Tricho needs phosphorous and iron, which also exist in the ocean in limited supply. With no way to regulate its growth, the turbo-boosted Tricho could burn through all of its available nutrients too quickly and abruptly die off, which would be catastrophic for all other life forms in the ocean that need the nitrogen it would have produced to survive.
Some models predict that increasing ocean acidification will exacerbate the problem of nutrient scarcity by increasing stratification of the ocean — locking key nutrients away from the organisms that need them to survive.
What the future may hold
Hutchins is collaborating with Eric bbb of USC Dornsife and Mak Saito of WHOI to gain a better understanding of what the future ocean will look like, as it continues to be shaped by climate change. They were shocked by the discovery of an evolutionary change that appears to be permanent — something Hutchins described as “unprecedented.”
“Tricho has been studied for ages. Nobody expected that it could do something so bizarre,” he said. “The evolutionary biologists are interested in it just to study this as a basic evolutionary principle.”
The team is now studying the DNA of Tricho to try to find out how and why the irreversible evolution occurs. Earlier this year, research led by Webb found that the organism’s DNA inexplicably contains elements that are usually only seen in higher life forms.
“Our results in this and the aforementioned study are truly surprising. Furthermore, they are giving us an improved view of how global climate change will impact Trichodesmium and the vital supplies of new nitrogen it provides to the rest of the marine food web in the future.” Webb said.
Hutchins, Webb and Saito collaborated with Nathan Walworth, Jasmine Gale and Fei-Xue Fu of USC; and Dawn Moran and Matthew McIlvin of WHOI. The work was funded by the National Science Foundation (grants OCE 1260490, OCE 1143760, OCE 1260233 and OCE OA 1220484); and the G.B. Moore Foundation (grants 3782 and 3934).
One of the most common things people have asked after reading the piece is, “What can I do to help?” So on Thursday afternoon, Holthaus, along with ten climate experts, participated in a Reddit AMA to answer readers’ questions about climate change solutions.
Below are some of the things we learned.
1. Climate experts aren’t all doom and gloom; they’re happy to offer solutions for “average” people. “Teach your children to be mindful of what they do. That waste causes problems. That they live in the context of a big world but that the world is made up of individual actions,” said marine ecologist Dr. Carl Safina.
“I would also add that ‘awareness’ is a key step forward. Talk about these issues with friends and families,” said Kansas State University grasslands ecologist Dr. Jesse Nippert, adding, “Engagement with others also has more relevance when it’s local – notice/record ‘small things’ in your community like changes in plant phenology (first flower, leaf drop), first freeze/thaw dates, rainfall amounts, etc….[C]itizen science has been a HUGE movement and source of invaluable data recording climate change.”
2. Some members of the public wish scientists would engage in more direct climate activism – and scientists have fascinating thoughts about that. “I am a believer that we all have things to contribute, and we do not all have to do the same things to be effective,” said Dr. Simone Alin, supervisory oceanographer at the NOAA Pacific Marine Environmental Laboratory. “I am glad people are marching in the streets to show how many people understand the problem and demand change. On the other hand, as a federal scientist, I have played a role in planning and implementing our regional, national, and international ocean acidification monitoring systems (with many, many great partners, from the policy world, academia, other gov’t agencies, tribal nations, industry, NGOs, etc.). In this capacity, others in my organization/field and I have had the opportunity to present our scientific findings to all of the above partners, all the way up to Congress, which has resulted in many positive outcomes.”
“I think we benefit more from mutually supporting each other and realizing we can be partners at the same table than from suggesting others aren’t doing enough because they are working through other channels,” she said.
3. The experts agree that modifying individual habits won’t be enough to combat climate change – we need to see big changes at the government level too. “We need both, to show our elected leaders we have skin in the game, but we need to demand that they take actions at the scale of their power,” said J. Drake Hamilton, senior policy director at Fresh Energy. “I have heard Congressmen crow about switching a few light bulbs — they need to sign into law comprehensive, market-based systems that put a limit/price on carbon pollution and internalize those external costs of climate.”
“The problem is too huge for the citizens to be making bottom-up changes; it is almost an imperative from the state/country to be leading the way,” said Dr. Nina Bednarsek, an ocean acidification scientist at the University of Washington and NOAA Pacific Marine Environmental Laboratory. “Having said that, citizens’ responsibility is to try to make these changes on the local and state level by writing to their politicians and demanding more green approaches.”
4. Climate scientists have a sense of humor. When asked if the AMA participants had any “crazy ideas [for] promoting climate change,” Dr. Alin responded, “A cooking show from the future. Premise: now that we only have jellyfish in our oceans, what tasty treats can we make out of them anyway?”
She added, “More seriously, I have thought for a long time that we need some sort of mechanism/agency/organization to quantify the overall footprint of human actions on the environment….All of our consumption choices and actions (flying, driving) have a total environmental footprint, but I’m not aware of anyone or any organization that calculates this….Ideally it should be an international entity (UN I suppose) that would create evidence-based metrics to support the sustainability of various lifestyle choices and such. I say this in part as a consumer – it can be mind-boggling enough to go to the supermarket and pick out a cereal in our world of needlessly plentiful choices – how’s a person to make important decisions about bigger consumption choices?”
5. There is hope. Maybe. Asked if climate change is reversible, Dr. Bill Peterson, an oceanographer at the NOAA Northwest Fisheries Science Center, had this to say: “We can only hope.”
Holthaus followed up on Dr. Peterson’s response, saying, “This is actually a pretty good answer from a scientific basis. There’s no way of knowing if future technology will be able to reliably and affordably remove excess carbon dioxide from the atmosphere, so the best current approach is not to put it there in the first place.”
Walruses, like these in Alaska, are being forced ashore in record numbers. Corey Accardo/NOAA/AP
The worst predicted impacts of climate change are starting to happen — and much faster than climate scientists expected
Historians may look to 2015 as the year when shit really started hitting the fan. Some snapshots: In just the past few months, record-setting heat waves in Pakistan and India each killed more than 1,000 people. In Washington state’s Olympic National Park, the rainforest caught fire for the first time in living memory. London reached 98 degrees Fahrenheit during the hottest July day ever recorded in the U.K.; The Guardian briefly had to pause its live blog of the heat wave because its computer servers overheated. In California, suffering from its worst drought in a millennium, a 50-acre brush fire swelled seventyfold in a matter of hours, jumping across the I-15 freeway during rush-hour traffic. Then, a few days later, the region was pounded by intense, virtually unheard-of summer rains. Puerto Rico is under its strictest water rationing in history as a monster El Niño forms in the tropical Pacific Ocean, shifting weather patterns worldwide.
On July 20th, James Hansen, the former NASA climatologist who brought climate change to the public’s attention in the summer of 1988, issued a bombshell: He and a team of climate scientists had identified a newly important feedback mechanism off the coast of Antarctica that suggests mean sea levels could rise 10 times faster than previously predicted: 10 feet by 2065. The authors included this chilling warning: If emissions aren’t cut, “We conclude that multi-meter sea-level rise would become practically unavoidable. Social disruption and economic consequences of such large sea-level rise could be devastating. It is not difficult to imagine that conflicts arising from forced migrations and economic collapse might make the planet ungovernable, threatening the fabric of civilization.”
Eric Rignot, a climate scientist at NASA and the University of California-Irvine and a co-author on Hansen’s study, said their new research doesn’t necessarily change the worst-case scenario on sea-level rise, it just makes it much more pressing to think about and discuss, especially among world leaders. In particular, says Rignot, the new research shows a two-degree Celsius rise in global temperature — the previously agreed upon “safe” level of climate change — “would be a catastrophe for sea-level rise.”
Hansen’s new study also shows how complicated and unpredictable climate change can be. Even as global ocean temperatures rise to their highest levels in recorded history, some parts of the ocean, near where ice is melting exceptionally fast, are actually cooling, slowing ocean circulation currents and sending weather patterns into a frenzy. Sure enough, a persistently cold patch of ocean is starting to show up just south of Greenland, exactly where previous experimental predictions of a sudden surge of freshwater from melting ice expected it to be. Michael Mann, another prominent climate scientist, recently said of the unexpectedly sudden Atlantic slowdown, “This is yet another example of where observations suggest that climate model predictions may be too conservative when it comes to the pace at which certain aspects of climate change are proceeding.”
Since storm systems and jet streams in the United States and Europe partially draw their energy from the difference in ocean temperatures, the implication of one patch of ocean cooling while the rest of the ocean warms is profound. Storms will get stronger, and sea-level rise will accelerate. Scientists like Hansen only expect extreme weather to get worse in the years to come, though Mann said it was still “unclear” whether recent severe winters on the East Coast are connected to the phenomenon.
And yet, these aren’t even the most disturbing changes happening to the Earth’s biosphere that climate scientists are discovering this year. For that, you have to look not at the rising sea levels but to what is actually happening within the oceans themselves.
Water temperatures this year in the North Pacific have never been this high for this long over such a large area — and it is already having a profound effect on marine life
Eighty-year-old Roger Thomas runs whale-watching trips out of San Francisco. On an excursion earlier this year, Thomas spotted 25 humpbacks and three blue whales. During a survey on July 4th, federal officials spotted 115 whales in a single hour near the Farallon Islands — enough to issue a boating warning. Humpbacks are occasionally seen offshore in California, but rarely so close to the coast or in such numbers. Why are they coming so close to shore? Exceptionally warm water has concentrated the krill and anchovies they feed on into a narrow band of relatively cool coastal water. The whales are having a heyday. “It’s unbelievable,” Thomas told a local paper. “Whales are all over the place.”
Last fall, in northern Alaska, in the same part of the Arctic where Shell is planning to drill for oil, federal scientists discovered 35,000 walruses congregating on a single beach. It was the largest-ever documented “haul out” of walruses, and a sign that sea ice, their favored habitat, is becoming harder and harder to find.
Marine life is moving north, adapting in real time to the warming ocean. Great white sharks have been sighted breeding near Monterey Bay, California, the farthest north that’s ever been known to occur. A blue marlin was caught last summer near Catalina Island — 1,000 miles north of its typical range. Across California, there have been sightings of non-native animals moving north, such as Mexican red crabs.
Salmon on the brink of dying out. Michael Quinton/Newscom
No species may be as uniquely endangered as the one most associated with the Pacific Northwest, the salmon. Every two weeks, Bill Peterson, an oceanographer and senior scientist at the National Oceanic and Atmospheric Administration’s Northwest Fisheries Science Center in Oregon, takes to the sea to collect data he uses to forecast the return of salmon. What he’s been seeing this year is deeply troubling.Salmon are crucial to their coastal ecosystem like perhaps few other species on the planet. A significant portion of the nitrogen in West Coast forests has been traced back to salmon, which can travel hundreds of miles upstream to lay their eggs. The largest trees on Earth simply wouldn’t exist without salmon.But their situation is precarious. This year, officials in California are bringing salmon downstream in convoys of trucks, because river levels are too low and the temperatures too warm for them to have a reasonable chance of surviving. One species, the winter-run Chinook salmon, is at a particularly increased risk of decline in the next few years, should the warm water persist offshore.”You talk to fishermen, and they all say: ‘We’ve never seen anything like this before,’ ” says Peterson. “So when you have no experience with something like this, it gets like, ‘What the hell’s going on?’ ”
Atmospheric scientists increasingly believe that the exceptionally warm waters over the past months are the early indications of a phase shift in the Pacific Decadal Oscillation, a cyclical warming of the North Pacific that happens a few times each century. Positive phases of the PDO have been known to last for 15 to 20 years, during which global warming can increase at double the rate as during negative phases of the PDO. It also makes big El Niños, like this year’s, more likely. The nature of PDO phase shifts is unpredictable — climate scientists simply haven’t yet figured out precisely what’s behind them and why they happen when they do. It’s not a permanent change — the ocean’s temperature will likely drop from these record highs, at least temporarily, some time over the next few years — but the impact on marine species will be lasting, and scientists have pointed to the PDO as a global-warming preview.
“The climate [change] models predict this gentle, slow increase in temperature,” says Peterson, “but the main problem we’ve had for the last few years is the variability is so high. As scientists, we can’t keep up with it, and neither can the animals.” Peterson likens it to a boxer getting pummeled round after round: “At some point, you knock them down, and the fight is over.”
Pavement-melting heat waves in India. Harish Tyagi/EPA/Corbis
Attendant with this weird wildlife behavior is a stunning drop in the number of plankton — the basis of the ocean’s food chain. In July, another major study concluded that acidifying oceans are likely to have a “quite traumatic” impact on plankton diversity, with some species dying out while others flourish. As the oceans absorb carbon dioxide from the atmosphere, it’s converted into carbonic acid — and the pH of seawater declines. According to lead author Stephanie Dutkiewicz of MIT, that trend means “the whole food chain is going to be different.”
The Hansen study may have gotten more attention, but the Dutkiewicz study, and others like it, could have even more dire implications for our future. The rapid changes Dutkiewicz and her colleagues are observing have shocked some of their fellow scientists into thinking that yes, actually, we’re heading toward the worst-case scenario. Unlike a prediction of massive sea-level rise just decades away, the warming and acidifying oceans represent a problem that seems to have kick-started a mass extinction on the same time scale.
Jacquelyn Gill is a paleoecologist at the University of Maine. She knows a lot about extinction, and her work is more relevant than ever. Essentially, she’s trying to save the species that are alive right now by learning more about what killed off the ones that aren’t. The ancient data she studies shows “really compelling evidence that there can be events of abrupt climate change that can happen well within human life spans. We’re talking less than a decade.”
For the past year or two, a persistent change in winds over the North Pacific has given rise to what meteorologists and oceanographers are calling “the blob” — a highly anomalous patch of warm water between Hawaii, Alaska and Baja California that’s thrown the marine ecosystem into a tailspin. Amid warmer temperatures, plankton numbers have plummeted, and the myriad species that depend on them have migrated or seen their own numbers dwindle.
Significant northward surges of warm water have happened before, even frequently. El Niño, for example, does this on a predictable basis. But what’s happening this year appears to be something new. Some climate scientists think that the wind shift is linked to the rapid decline in Arctic sea ice over the past few years, which separate research has shown makes weather patterns more likely to get stuck.
A similar shift in the behavior of the jet stream has also contributed to the California drought and severe polar vortex winters in the Northeast over the past two years. An amplified jet-stream pattern has produced an unusual doldrum off the West Coast that’s persisted for most of the past 18 months. Daniel Swain, a Stanford University meteorologist, has called it the “Ridiculously Resilient Ridge” — weather patterns just aren’t supposed to last this long.
What’s increasingly uncontroversial among scientists is that in many ecosystems, the impacts of the current off-the-charts temperatures in the North Pacific will linger for years, or longer. The largest ocean on Earth, the Pacific is exhibiting cyclical variability to greater extremes than other ocean basins. While the North Pacific is currently the most dramatic area of change in the world’s oceans, it’s not alone: Globally, 2014 was a record-setting year for ocean temperatures, and 2015 is on pace to beat it soundly, boosted by the El Niño in the Pacific. Six percent of the world’s reefs could disappear before the end of the decade, perhaps permanently, thanks to warming waters.
Since warmer oceans expand in volume, it’s also leading to a surge in sea-level rise. One recent study showed a slowdown in Atlantic Ocean currents, perhaps linked to glacial melt from Greenland, that caused a four-inch rise in sea levels along the Northeast coast in just two years, from 2009 to 2010. To be sure, it seems like this sudden and unpredicted surge was only temporary, but scientists who studied the surge estimated it to be a 1-in-850-year event, and it’s been blamed on accelerated beach erosion “almost as significant as some hurricane events.”
Biblical floods in Turkey. Ali Atmaca/Anadolu Agency/Getty
Possibly worse than rising ocean temperatures is the acidification of the waters. Acidification has a direct effect on mollusks and other marine animals with hard outer bodies: A striking study last year showed that, along the West Coast, the shells of tiny snails are already dissolving, with as-yet-unknown consequences on the ecosystem. One of the study’s authors, Nina Bednaršek, told Science magazine that the snails’ shells, pitted by the acidifying ocean, resembled “cauliflower” or “sandpaper.” A similarly striking study by more than a dozen of the world’s top ocean scientists this July said that the current pace of increasing carbon emissions would force an “effectively irreversible” change on ocean ecosystems during this century. In as little as a decade, the study suggested, chemical changes will rise significantly above background levels in nearly half of the world’s oceans.
“I used to think it was kind of hard to make things in the ocean go extinct,” James Barry of the Monterey Bay Aquarium Research Institute in California told the Seattle Times in 2013. “But this change we’re seeing is happening so fast it’s almost instantaneous.”
Thanks to the pressure we’re putting on the planet’s ecosystem — warming, acidification and good old-fashioned pollution — the oceans are set up for several decades of rapid change. Here’s what could happen next.
The combination of excessive nutrients from agricultural runoff, abnormal wind patterns and the warming oceans is already creating seasonal dead zones in coastal regions when algae blooms suck up most of the available oxygen. The appearance of low-oxygen regions has doubled in frequency every 10 years since 1960 and should continue to grow over the coming decades at an even greater rate.
So far, dead zones have remained mostly close to the coasts, but in the 21st century, deep-ocean dead zones could become common. These low-oxygen regions could gradually expand in size — potentially thousands of miles across — which would force fish, whales, pretty much everything upward. If this were to occur, large sections of the temperate deep oceans would suffer should the oxygen-free layer grow so pronounced that it stratifies, pushing surface ocean warming into overdrive and hindering upwelling of cooler, nutrient-rich deeper water.
Enhanced evaporation from the warmer oceans will create heavier downpours, perhaps destabilizing the root systems of forests, and accelerated runoff will pour more excess nutrients into coastal areas, further enhancing dead zones. In the past year, downpours have broken records in Long Island, Phoenix, Detroit, Baltimore, Houston and Pensacola, Florida.
Evidence for the above scenario comes in large part from our best understanding of what happened 250 million years ago, during the “Great Dying,” when more than 90 percent of all oceanic species perished after a pulse of carbon dioxide and methane from land-based sources began a period of profound climate change. The conditions that triggered “Great Dying” took hundreds of thousands of years to develop. But humans have been emitting carbon dioxide at a much quicker rate, so the current mass extinction only took 100 years or so to kick-start.
With all these stressors working against it, a hypoxic feedback loop could wind up destroying some of the oceans’ most species-rich ecosystems within our lifetime. A recent study by Sarah Moffitt of the University of California-Davis said it could take the ocean thousands of years to recover. “Looking forward for my kid, people in the future are not going to have the same ocean that I have today,” Moffitt said.
As you might expect, having tickets to the front row of a global environmental catastrophe is taking an increasingly emotional toll on scientists, and in some cases pushing them toward advocacy. Of the two dozen or so scientists I interviewed for this piece, virtually all drifted into apocalyptic language at some point.
For Simone Alin, an oceanographer focusing on ocean acidification at NOAA’s Pacific Marine Environmental Laboratory in Seattle, the changes she’s seeing hit close to home. The Puget Sound is a natural laboratory for the coming decades of rapid change because its waters are naturally more acidified than most of the world’s marine ecosystems.
The local oyster industry here is already seeing serious impacts from acidifying waters and is going to great lengths to avoid a total collapse. Alin calls oysters, which are non-native, the canary in the coal mine for the Puget Sound: “A canary is also not native to a coal mine, but that doesn’t mean it’s not a good indicator of change.”
Though she works on fundamental oceanic changes every day, the Dutkiewicz study on the impending large-scale changes to plankton caught her off-guard: “This was alarming to me because if the basis of the food web changes, then . . . everything could change, right?”
Alin’s frank discussion of the looming oceanic apocalypse is perhaps a product of studying unfathomable change every day. But four years ago, the birth of her twins “heightened the whole issue,” she says. “I was worried enough about these problems before having kids that I maybe wondered whether it was a good idea. Now, it just makes me feel crushed.”
Katharine Hayhoe, a climate scientist and evangelical Christian, moved from Canada to Texas with her husband, a pastor, precisely because of its vulnerability to climate change. There, she engages with the evangelical community on science — almost as a missionary would. But she’s already planning her exit strategy: “If we continue on our current pathway, Canada will be home for us long term. But the majority of people don’t have an exit strategy. . . . So that’s who I’m here trying to help.”
James Hansen, the dean of climate scientists, retired from NASA in 2013 to become a climate activist. But for all the gloom of the report he just put his name to, Hansen is actually somewhat hopeful. That’s because he knows that climate change has a straightforward solution: End fossil-fuel use as quickly as possible. If tomorrow, the leaders of the United States and China would agree to a sufficiently strong, coordinated carbon tax that’s also applied to imports, the rest of the world would have no choice but to sign up. This idea has already been pitched to Congress several times, with tepid bipartisan support. Even though a carbon tax is probably a long shot, for Hansen, even the slim possibility that bold action like this might happen is enough for him to devote the rest of his life to working to achieve it. On a conference call with reporters in July, Hansen said a potential joint U.S.-China carbon tax is more important than whatever happens at the United Nations climate talks in Paris.
One group Hansen is helping is Our Children’s Trust, a legal advocacy organization that’s filed a number of novel challenges on behalf of minors under the idea that climate change is a violation of intergenerational equity — children, the group argues, are lawfully entitled to inherit a healthy planet.
A separate challenge to U.S. law is being brought by a former EPA scientist arguing that carbon dioxide isn’t just a pollutant (which, under the Clean Air Act, can dissipate on its own), it’s also a toxic substance. In general, these substances have exceptionally long life spans in the environment, cause an unreasonable risk, and therefore require remediation. In this case, remediation may involve planting vast numbers of trees or restoring wetlands to bury excess carbon underground.
Even if these novel challenges succeed, it will take years before a bend in the curve is noticeable. But maybe that’s enough. When all feels lost, saving a few species will feel like a triumph.
The warming of the oceans due to climate change is now unstoppable after record temperatures last year, bringing additional sea-level rise, and raising the risks of severe storms, US government climate scientists said on Thursday.
The annual State of the Climate in 2014 report, based on research from 413 scientists from 58 countries, found record warming on the surface and upper levels of the oceans, especially in the North Pacific, in line with earlier findings of 2014 as the hottest year on record.
Global sea-level also reached a record high, with the expansion of those warming waters, keeping pace with the 3.2 ± 0.4 mm per year trend in sea level growth over the past two decades, the report said.
Scientists said the consequences of those warmer ocean temperatures would be felt for centuries to come – even if there were immediate efforts to cut the carbon emissions fuelling changes in the oceans.
“I think of it more like a fly wheel or a freight train. It takes a big push to get it going but it is moving now and will contiue to move long after we continue to pushing it,” Greg Johnson, an oceanographer at Noaa’s Pacific Marine Environmental Laboratory, told a conference call with reporters.
“Even if we were to freeze greenhouse gases at current levels, the sea would actually continue to warm for centuries and millennia, and as they continue to warm and expand the sea levels will continue to rise,” Johnson said.
On the west coast of the US, freakishly warm temperatures in the Pacific – 4 or 5F above normal – were already producing warmer winters, as well as worsening drought conditions by melting the snowpack, he said.
The extra heat in the oceans was also contributing to more intense storms, Tom Karl, director of Noaa’s National Centers for Environmental Information, said.
The report underlined 2014 as a banner year for the climate, setting record or near record levels for temperature extremes, and loss of glaciers and sea ice, and reinforcing decades-old pattern to changes to the climate system.
Four independent data sets confirmed 2014 as the hottest year on record, with much of that heat driven by the warming of the oceans.
Globally 90% of the excess heat caused by the rise in greenhouse gas emissions is absorbed by the oceans.
More than 20 countries in Europe set new heat records, with Africa, Asia and Australia also experiencing near-record heat. The east coast of North America was the only region to experience cooler than average conditions.
Alaska experienced temperatures 18F warmer than average. Spring break-up came to the Arctic 20-30 days earlier than the 20th century average.
“The prognosis is to expect a continuation of what we have seen,” Karl said.
If greenhouse gas emissions are not curtailed soon, then global warming may bring about the most sweeping re-arrangement of ocean species in at least 3 million years, according to a new study.
The study, published Monday in the journal Nature Climate Change, shows that by the end of the century, the polar regions may be have some of the most abundant and diverse sea life of anywhere on the planet, while the tropics, which are currently the crown jewel of marine species richness, may be drained of much of its iconic marine life.
The stakes involved in which ocean species live where are high since, globally, we depend on proteins derived from fish, crustaceans and mollusks for up to a quarter of our animal protein intake, according to the World Health Organization. In 2010, fish provided more than 2.9 billion people with almost 20% of their intake of animal protein, according to the Marine Stewardship Council, and 4.3 billion people with about 15% of such protein. In some countries, these figures are higher.
The study, which attempts to quantify the shifts in biodiversity that may occur during this century throughout the global ocean, offers a stark warning ahead of global climate talks in Paris in December.
It finds that global warming may not alter the oceans in a profound way if emissions are cut sufficiently to meet the globally agreed upon temperature target of 2 degrees Celsius, or 3.6 degrees Fahrenheit, compared to preindustrial levels. Some policymakers now consider that goal to be nearly impossible, given the continued rise in planet-warming greenhouse gases such as carbon dioxide.
Emissions over next few years determine ocean’s destiny
If warming is held at the 2-degree target, says study co-author Richard Kirby, the changes that will occur throughout the global ocean “will be relatively benign for the ecosystem.” Kirby is affiliated with the Marine Biological Association in the U.K..
Study coauthor Grégory Beaugrand, a senior researcher at an ocean laboratory in Lille, France, and a consultant at the Sir Alister Hardy Foundation for Ocean Science in the U.K., says that tropical regions would see a net loss in biodiversity with average global warming of 2 degrees Celsius, while polar areas could see a 300% increase in biodiversity as species seek out more hospitable areas.
A tuna fish swims in the large tank at the Tokyo Sea Life Park in Tokyo on March 25, 2015. Image: TOSHIFUMI KITAMURA/AFP/Getty Images
However, if emissions stay on their current, high path, then in just the span of one century, there could be a larger biodiversity shift than the global oceans saw since the mid-Pliocene period more than 3 million years ago.
This would be a staggering amount of change in such a short time period, which could result in many surprises that scientists don’t yet anticipate. It would also present unprecedented challenges for the fishing industry, which is locally adapted to catching present-day species, including the rapidly-growing global aquaculture industry.
As species migrate toward the poles, fishing fleets will have to be remodeled to hunt for a new mix of species. This has occurred already in Newfoundland and parts of the northeast U.S., where the cod fishery has collapsed, giving way to more of a lobster and crab fishery. This shift is not an easy one to make, since crab fishing requires totally different gear than hunting groundfish species like cod and haddock.
“The transition period will have a devastating impact on fisherman and from a socioeconomic point of view,” Beaugrand told Mashable.
Even a moderate warming that is less than a worst-case scenario could yield a major reorganization of marine biodiversity over large oceanic regions by the 2081-2100 period. These changes may be at least three times greater than the shifts observed between the years 1960-2013, the study found.
Exceeding the 2 degrees Celsius target, Beaugrand said in an interview, would mean that “between 78 and 95% of the ocean will show substantial changes” in biodiversity by the end of the century.
Species are already packing up and heading away from the equator
Unlike terrestrial species, marine creatures can and already are migrating in search of more suitable environments once temperatures exceed their tolerable ranges. This has been seen in several studies of the North Sea in particular, where shifts in the amount and types of plankton and other foraminifera as well as commercially-prized fish have been observed.
In the northeast Atlantic, for example, plankton, which are organisms that produce oxygen through photosynthesis and form the foundation of the marine food web, have already shifted northward by 10 degrees of latitude due in part to ocean temperature increases in that region.
Kirby says that people tend to forget that humans depend on temperature-sensitive organisms as tiny as plankton. “The rest of life on earth lives where the temperature suits it. If that changes, it moves, in sea it tends to move because it can,” he said. “It’s those movements, especially lower down in the food web, that underpin the whole marine food chain upon which we depend.”
Somalian fisherman carries swordfish on his head from the port to the fish market on the eastern Curubo beach of the Somalian capital city of Mogadishu, on November 24, 2014.
When looking at changes between 1960 and 2013, the study found that 30% of the area of ocean already showed substantial changes in biodiversity, “which is six times higher” than changes due to natural variability alone, Beaugrand said.
“Climate change already has an impact on marine biodiversity,” he says.
A severe global warming scenario featuring continued emissions growth through the end of the century could cause between 50 to 70% of the world’s oceans to experience a change in marine biodiversity comparable or more extensive that those that occurred since the mid-Pliocene and today, as well as since the last glacial maximum — when thick ice sheets covered areas from Washington, D.C., to Seattle and northward.
“It’s really worrying, because this is the whole ocean that will change,” Beaugrand says.
The mid-Pliocene is of interest because it was the last time that climate conditions are thought to have been similar to what is projected for the end of the century. At that time, global carbon dioxide concentrations were about 400 parts per million, which is where it stands now, and global average temperatures were 2 to 3 degrees Celsius (3.6 to 5.4 degrees Fahrenheit) higher than today. Global sea levels were about 66 feet higher than today, as well.
An Indian fisherman cleans fish in the river Brahmaputra in Gauhati, Assam state, India, Sunday, April 19, 2015. Image: Anupam Nath/Associated Press
The last glacial maximum lasted from about 26,500 to 20,000 years ago. During this time period, the amount of carbon dioxide in the air was just 190 parts per million, according to the study, and the average sea level was 425 feet below current levels.
Between the last glacial maximum and today, about 85% of the global ocean area showed substantial modification in marine biodiversity, Beaugrand said, while between the mid-Pliocene and today, 75% of the global ocean showed substantial changes. Yet this all played out over thousands to millions of years, not in just a century, which is the timeline we’re looking at with regards to manmade global warming.
In other words, there’s no precedent in all of human history for what may be about to happen, which is extraordinarily risky given that we depend on the oceans for ecosystem services from food to oxygen production and heat storage.
Generating ‘pseudo species’
The study used a theoretical model that relies upon fundamental ecological principles and previously known findings of how biodiversity changes with temperature fluctuations to come up with, essentially, “pseudo marine communities,” as the study refers to them. The authors compared the modeled biodiversity patterns to observed patterns based on previous studies, and found that there was a statistically significant amount of agreement.
The study allowed tens of thousands of modeled species, each with different biological properties including temperature ranges, to colonize the ocean. The researchers used data from deep sea sediment cores to look at how plankton groups have changed through time in order to fine-tune their modeling results.
One drawback to this study, as well as others that focus on global ocean species, is that we know more about Mars than we do about much of the ocean. So far, Beaugrand says, we’ve only described the characteristics of about 200,000 marine species, which is about 10% of the marine biodiversity that scientists think is out there. We have an incomplete knowledge of marine biology and spatial distribution — that could limit the reliability of studies like this to some extent.
Another wild card is exactly how ocean acidification, which is also caused by climate change, will alter marine biodiversity and functioning of marine ecosystems. Such studies are currently in their infancy.
Sea urchins disappeared for thousands of years during ancient warming periods that could be a model of future climate change, a new study shows. Here, the shells of modern sea urchins lie in a tide pool in Corona del Mar. (Glenn Koenig / Los Angeles Times)
By Geoffrey Mohan
Naturally occurring climate change lowered oxygen levels in the deep ocean, decimating a broad spectrum of seafloor life that took some 1,000 years to recover, according to a study that offers a potential window into the effects of modern warming.
Earth’s recovery from the last glacial period, in fact, was slower and more brutal than previously thought, according to the study, published online Monday in the journal Proceedings of the National Academy of Sciences.
Researchers deciphered that plotline from a 30-foot core of sea sediments drilled from the Santa Barbara Basin containing more than 5,000 fossils spanning nearly 13,000 years.
“The recovery does not happen on a century scale; it’s a commitment to a millennial-scale recovery,” said Sarah Moffitt, a marine ecologist at UC Davis’ Bodega Marine Laboratory and lead author of the study. “If we see dramatic oxygen loss in the deep sea in my lifetime, we will not see a recovery of that for many hundreds of years, if not thousands or more.”
Studies already have chronicled declines in dissolved oxygen in some areas of Earth’s oceans. Such hypoxic conditions can expand when ocean temperatures rise and cycles that carry oxygen to deeper areas are interrupted.
As North American glaciers retreated during a warming period 14,700 years ago, an oxygen-sensitive community of seafloor invertebrates that included sea stars, urchins, clams and snails nearly vanished from the fossil record within about 130 years, the researchers found.
“We found incredible sensitivity across all of these taxonomic groups, across organisms that you would recognize, that you could hold in your hand, organisms that build and create ecosystems that are really fundamental to the way ecosystems function,” Moffitt said. “They were just dramatically wiped out by the abrupt loss of oxygen.”
That highly diverse community soon was replaced with a relatively narrow suite of bizarre and extreme organisms similar to those found near deep-ocean vents and methane seeps in modern oceans, Moffitt said.
Evidence of that transition was confined to such a narrow band of sediments that the turnover could have been “nearly instantaneous,” the study concluded.
Then, beginning around 13,500 years ago, the seafloor community began a slow recovery with the rise of grazers that fed on bacterial mats. Recovery eventually was driven by a fluctuation back toward glaciation during the Younger Dryas period, a cooling sometimes called the Big Freeze.
“The biological community takes 1,000 years to truly recover to the same ecological level of functioning,” Moffitt said. “And the community progresses through really interesting and bizarre states before it recovers the kind of biodiversity that was seen prior to the warming.”
That relatively brief freeze also ended abruptly around 11,700 years ago, virtually wiping out all the seafloor metazoans, the study found. They were gone within 170 years and did not appear again for more than 4,000 years, according to the study.
The climate changes chronicled in the study arose from natural cycles involving Earth’s orbit of the sun, and the oxygen declines that ensued were more extreme than those that have occurred in modern times, the study noted.
Still, the abrupt fluctuations offer a glimpse at the duration of the effects of climate change driven by human activity pumping more planet-warming gases into Earth’s atmosphere, Moffitt said.
“What this shows us is that there are major biomes on this planet that are on the table, that are on the chopping block for a future of abrupt climate warming and unchecked greenhouse gas emissions,” Moffitt said. “We as a society and civilization have to come to terms with the things that we are going to sacrifice if we do not reduce our greenhouse gas footprint.”
California sea lion pups keep washing up on the state’s coastline at abnormally high numbers: more than 1,800 starving pups have been brought into rescue facilities already this year, officials reported Tuesday.
The average yearly intake for stranded pups is about 200.
Justin Viezbicke, California Stranding Network coordinator for the National Marine Fisheries Service, said that he’s asking the public to be patient when it comes to rescue attempts for emaciated pups.
He said that the network won’t be able to rescue all pups and efforts to do so would hurt its ability to treat animals already in house. About 750 sea lions are being held for treatment in facilities right now.
“If we go over too many animals, the care really is lessened for all of those animals, and they all have decreased chances of survival,” Viezbicke said “Whereas, if we can focus on the ones we know we can give the best care and have the best chance of survival, we at least are giving them the best shot.”
Even reaching treatment centers is no guarantee of survival for the pups. Some are judged to be too far gone and are euthanized. Others die while undergoing treatment.
Even the ones that are successfully treated and released face difficult survival prospects. Unusually warm water off the coast holds less prey for the sea lions to forage.
“The reality is we’re putting them back into a very challenging situation, so there’s no guarantee that these animals that are being rehabbed are going to survive. It’s something we’ll be watching and monitoring for the future,” Viezbicke said.
The warm water is believed to be the cause of the high number of strandings in the first place.
As nursing mothers spend more time away on hunting trips seeking out that ever elusive prey, starving young leave their rookeries far earlier than they normally would.
Scientists said that the population of California sea lions is still strong, with estimates of total size at around 300,000 individuals.
The population has doubled from decades ago and the increased competition may be contributing to the poor feeding conditions, according to Nate Mantua, a climatologist with NOAA Fisheries.
Climate change not culpable … yet
He said the warm water isn’t likely caused by global warming because its development was too recent and too regional.
“It doesn’t look to me like a global warming pattern. It’s a direct response to the regional wind patterns that have been so persistent — including the pattern that brought us drought,” Mantua said. “I don’t really see the hallmarks of a global warming signature.”
A lack of winds from the north has kept surface water from being pushed out from the coast. That has lessened the amount of nutrient-rich upwelling of colder water.
The sea surface temperature map shows the unusually warm ocean water encompassing the West Coast. Darker red indicates temperatures farther above average. Credit: NOAA Fisheries/Southwest Fisheries Science Center.
No end in sight
Mantua said the northerly winds that normally accompany the start of spring are beginning to appear in Northern California. If they persist, he said some colder water could emerge nearer to land. That could help.
But he said the effect would be localized and that a recently declared El Niño appears to be strengthening — a combination that means the warm water could last for another year.
“The bigger picture, you step back and look at the whole broad region of the Northeast Pacific Ocean, it’s likely to stay warm for much of this year,” he said.
“Unless we get a winter next year that’s more normal and a lot stormier,” he added, “I think that it might persist. And if the El Niño develops, then it becomes even more likely to persist all the way to the end of the year and to next spring.”
Even though climate change isn’t a large factor in the current water temperature rise, Mantua said models predict it will become the major cause for future warmer water.
“When we get towards the middle of this century, human-caused climate change is going to be equal and then dominant for the warming trends along the West Coast,” Mantua said.
2013 was bad, too
This is the second time in a few years that California sea lion pups have stranded at abnormally high rates. In 2013, NOAA declared an unusual mortality event for the species.
Viezbicke, of the California Stranding Network, said it would take several years of similar mass deaths to reduce numbers to a threatened level because sea lion populations are so big right now.
In fact, events like this may even strengthen the remaining population.
“Even in naturally occurring situations like this, Mother Nature can kind of control the population size out there, and those that are doing well — that are currently in this warm water situation — will probably continue to do ok,” Viezbicke said. “And those that don’t, will kind of be weeded out from the gene pool.”