Greenland Is Losing More Ice Than Scientists Thought
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The spots on the Greenland ice sheet that have a direct connection to the ocean are losing mass the fastest, scientists found. Shown here, Helheim Glacier in southeast Greenland.
Bad news keeps flowing for the icy landscapes of the world.
Rising temperatures are melting ice and sending it to the ocean, a process that is pushing sea levels higher and altering the landscape at both poles. The latest news comes from Greenland, where researchers have used high-tech satellite and GPS measurements to see how much mass the ice sheet is losing.
Their results, published this week in Science Advances, indicate that it's melting faster than previous estimates, particularly in areas where the ice sheet comes in direct contact with the ocean. It's a troubling finding for the future of coastal areas around the world.
The Greenland ice sheet contains enough water that, if melted, would raise sea levels up to 23 feet. Rising temperatures have already eaten away at it, and Greenland's ice sheet is responsible for about 30 percent of the observed foot of sea level rise since the start of the 20th century. While the rest of the ice sheet isn't going to disappear overnight, it's fate is intimately tied to the fate of communities along the coast.
"Greenland is one of the more pronounced contributors to sea level rise," Michael Willis, a remote sensing expert at the Cooperative Institute for Research in Environmental Sciences and co-author of the study, said. "In order to know how Greenland's ice may change in the future, we need to focus on the areas where the changes have occurred over both short and long time periods."
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Because of Greenland's remoteness and sheer mass, measuring changes is a challenge. The land under the ice sheet also adds another wrinkle. Ice started receding due to natural forces 20,000 years ago, and the land underneath has been slowly rising in response.
The Gravity Recovery and Climate Experiment (GRACE), the satellites tasked with measuring the mass changes in Greenland and other icy landscapes around the world, has a hard time time seeing the difference between rising land and ice.
"GRACE can only measure mass change," Willis said. "It cannot tell you what is changing mass."
To get that end of the equation, Willis and his colleagues turned to GPS sensors set up across Greenland. Comparing them to satellite data, they found that the Greenland ice sheet was losing mass 8 percent faster than previous estimates.
The areas losing mass the fastest are spots where the ice sheet has a direct connection to the ocean. Rising ocean waters and air temperatures are essentially putting ice in a vise grip of warming and speeding up melt. Geology is also compounding the rapid loss of ice in those regions.
"The ice sheet in these basins is also steeper than the average for the ice sheet, therefore the ice flows, on average, faster there, too," Willis said. "Simply put, the shape of the ice sheet and the contact with the ocean makes it likely that these areas respond more pronouncedly to changes in climate boundary conditions — be they atmospheric, oceanic or glaciological."
The revised mass loss estimates will provide an important tool for researchers going forward as they estimate sea level rise as well as the potential for an even more dramatic slowdown in Atlantic ocean circulation.
"The finding shows the precision of the state of the art in mass budget work," Jason Box, an ice sheet researcher at the Geological Survey of Denmark and Greenland, said in an email. "Being that precise with a 2-mile thick dome of ice three times the acreage of Texas ain't bad."
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Original story on Climate Central.
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Atlantic white cedars dying near the banks of the Bass River in New Jersey.
Credit: Ted Blanco, Climate Central
OCEAN COUNTY, N.J. — Jennifer Walker stepped off her kayak into a wall of riverside grass. She steadied herself and stooped to scoop soil into a jar, then disappeared into the thicket for more. Analysis of amoeba fossils in the researcher's samples may help to explain why, jutting above the head-high marsh grass a couple hundred feet further back, cedar forest was dead.
Bare trunks of dead coastal forests are being discovered up and down the mid-Atlantic coastline, killed by the advance of rising seas. The "ghost forests," as scientists call them, offer eerie evidence of some of the world's fastest rates of sea level rise.
Forests provide habitat and protect against global warming, but they're declining worldwide because of land clearing, fires, disease and invasive species. The ghost forests show sea level rise can be yet another cause of deforestation.
Climate scientists like Walker, a PhD candidate at Rutgers University researching sea level rise, have begun investigating these dead forests, which are becoming common features along some coastal landscapes. The poison that kills the trees is salt, delivered to their roots by rising tides.
"As you have sea level rise, you get saltwater intrusion further upstream," Walker said. The "visual impact" of the dead trees could be useful for "communicating sea level rise to the public," she said — "which I find difficult a lot of the time."
Stands of dead trees have been used by scientists for decades as evidence of past environmental tumult. When submerged in seas and lakes, dead trees have revealed to scientists the details of prehistoric changes in water levels.
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Seas are rising worldwide because of the warming effects of greenhouse gas pollution from fossil fuels and farms. Several feet of sea level rise is projected this century as the pace of climate change accelerates. That rise will inundate infrastructure, homes and ecosystems. Efforts to switch to clean energy, protect forests and revamp farming and transportation could curb the inundations ahead.
The mid-Atlantic is sinking faster than nearly anywhere else. The Gulf Stream has been shifting northward, bringing warmer water to the region, accelerating sea level rise. Meanwhile, groundwater pumping and natural geological processes are causing lands to sink.
High tides rose here by several inches during a recent decade. That was more than three times faster than the average rate of sea level rise worldwide, simulating conditions expected globally during decades to come.
Walker is part of a team that has begun investigating the ghost forests along the estuaries of southern New Jersey, accessing research sites using trucks and kayaks.
Similar forest diebacks have been documented in Canada and Louisiana and monitored in wildlife refuges in Maryland. The botanical corpses occasionally topple during storms, becoming crisscrossed logs, which are slowly buried beneath the muck of marshes. Those marshes can migrate inland as seas rise.
"Those trees die back and it converts to a tidal marsh," said Matt Whitbeck, a biologist at the Blackwater National Wildlife Refuge in Maryland, where rising seas have killed several thousand acres of forest since the 1930s.
Preliminary findings from an analysis by Virginia Institute of Marine Science (VIMS) scientists suggests 100,000 acres of coastal forest may have died off around the edges of the Chesapeake Bay since the 1850s. Much of the dead forest has now been replaced by marshland, while former marsh areas are now open water. Overall, the changes are diminishing the ability of plants in the region to fight global warming by absorbing carbon dioxide.
"Even in the three years I've been at VIMS, I've seen that process take place," said Matt Kirwan, a coastal landscape researcher who is leading the analysis. "We had some really high tides in October of last year that killed trees off, and now new marshes are forming under them."
The VIMS research has focused heavily on Goodwin Island, a windswept study site near the mouth of the Chesapeake. Accessible only by boat, the undeveloped island contains hundreds of acres of forests and marshes — teeming with tiny crabs and even tinier ticks.
"At Goodwin Island, we see the process where the forest is being replaced by marsh very clearly," Kirwan said. "We have maps from the 1850s that show there was roughly twice as much forest on the island as there is today."
The ghost forests are visual testaments to the power of rising seas in refashioning environments and ecosystems. With mapping and radiocarbon dating efforts planned by Rutgers, combined with soil sampling and other approaches for studying landscapes, these ghost forests could reveal the history of the region's shorelines.
"They could be very useful indicators of past sea level change," said Ben Horton, a Rutgers professor who studies sea level rise. He is Walker's PhD supervisor. "How did the landscape respond to any pulses in sea level? That gives us context for what will happen in the future."
Horton thinks many of the ghost forests of New Jersey that are still standing died during the past century. Sticking out of the mud of rivers and riverbanks are the stumps of trees that may have been killed hundreds of years earlier.
"Along much of the Jersey shore you can see these now," Horton said. "I've seen it throughout Jersey, I've seen it in Virginia, I've seen it in North Carolina. I'm sure you could observe it elsewhere."
Forest die-offs from rising seas occurred in centuries and millennia past when New Jersey was a natural wonderland, when forestlands could migrate upland as salty water brushed their subterranean toes.
Now, though, New Jersey's forests are boxed between shifting shores and farmland. Like forests elsewhere, these woodlands shelter wildlife and are popular with hunters and hikers. They help slow global warming by sucking up carbon dioxide pollution.
As seas continue to rise they seem certain to continue killing coastal forests, leaving only the specters of logs behind. In New Jersey, as elsewhere, that will mean less forestland — unless humans or nature find ways of fostering seedlings in fields currently used for farming.
"All these areas are backed up by agriculture," Horton said. "We want to protect our woodlands, but they've got to have somewhere to go."
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Originally published on Climate Central.
Climate Change to Opioids: Presidential Candidates Answer 20 Science Questions
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Call it a presidential game of 20 questions: The 2016 U.S. presidential candidates recently answered a slew of questions about science-related issues, offering a glimpse of their stances on everything from vaccinations to climate change to the country's growing opioid problem.
ScienceDebate, a coalition of 56 leading U.S. nonpartisan organizations representing more than 10 million scientists and engineers, called on the candidates to give their stance on top science, engineering, technology, health and environmental questions facing the country.
In their responses, Democratic candidate Hillary Clinton and Republican candidate Donald Trump touched on specific government programs and spending priorities, but the candidates diverged wildly on approaches to science policy. [Democratic Party Platform: We Fact-Checked the Science]
Climate change, in particular, was a hot-button issue.
A warming planet
Clinton said the science of climate change is "crystal clear" and the issue is "an urgent threat and a defining challenge of our time." The Democratic candidate outlined her plan to address the issue, which focused on making America "the clean-energy superpower of the 21st century."
A growing body of scientific evidence confirms that human activities are contributing to rapid climate change, and scientists have warned that if the gradual heating of the Earth does not slow, the repercussions could be devastating. Recent data from NASA suggest that 2016 is on track to be the hottest year on record. In fact, 16 of the hottest years on record fall within the past two decades, according to the National Oceanic and Atmospheric Administration (NOAA). Melting ice sheets, rising global sea levels, collapsing ecosystems and an increased risk of extreme weather are some of the consequences of global warming, scientists have said.
For Trump, the issue of climate change was referred to in quotation marks. He said, "There is still much that needs to be investigated in the field." While the candidate noted the need for new energy sources to alleviate America's dependence on fossil fuels, he did not directly respond to how he would tackle the issue of climate change if elected. Instead, Trump offered alternative uses for the country's limited financial resources, such as increasing food production or fighting malaria. [We Fact-Checked the Science Behind the Republican Party Platform]
A growing problem
On the topic of opioids, ScienceDebate asked candidates how they would enlist researchers, medical doctors and pharmaceutical companies in addressing this issue. Powerful prescription painkillers — like hydrocodone (marketed as Vicodin), oxycodone (OxyContin, Percocet), morphine (Kadian, Avinza) and codeine — are highly addictive and dangerous with misuse.
Trump's solution to the growing prescription drug problem was to "stop the inflow of opioids into the United States," something he said his administration can and will do.
In Clinton's response, she noted that 52 million Americans over age 12 have misused prescription drugs. Clinton said the government must work with medical professionals to treat the issue on the ground, from how patients access the medications to how they are supported in recovery. Beyond opioids, Clinton discussed the need to combat all drug and alcohol addiction. She described a proposed $10 billion initiative that would support prevention, treatment, recovery and other areas of reform.
Presidential platforms
Beyond the science issues, the candidates also varied in the format of their responses. In general, Trump questioned the need for the federal government's involvement in a number of scientific issues, such as agriculture and ocean health. His answers were also short and took a broader approach in addressing the questions.
For instance, in response to the last question on scientific integrity — in which ScienceDebate asked candidates how they will ensure scientific evidence is transparent and free from political biases and pressure — Trump said:
"Science is science and facts are facts. My administration will ensure that there will be total transparency and accountability without political bias. The American people deserve this and I will make sure this is the culture of my administration." [6 Politicians Who Got the Science Wrong]
In contrast, Clinton was very detailed in her responses and outlined not only the role of the government but also specific plans for her presidency. To the same scientific integrity question, Clinton explained how her efforts would "ensure a culture of scientific integrity," which included the facilitation of open communication and public engagement. Clinton also discussed her concern over the interference of partisan political efforts in scientific endeavors and called for "the free exchange of ideas and data" and federal policies to reinforce public trust in the integrity of science.
One issue the candidates all agreed on was the need to expand the space program, including the importance of exploration and its inspirational aspects. Trump noted that a strong space program inspires students to pursue the so-called STEM fields (science, technology, engineering and mathematics), while Clinton shared her personal awe of space and commended NASA's efforts thus far. Green Party candidate Jill Stein called for demilitarized and internationally collaborative space exploration.
Libertarian Party nominee Gary Johnson had not yet responded at the time of publication.
The candidates' full answers to all 20 questions can be found on the Science Debate website.
Original article on Live Science.
August Declared Hottest on Record: NASA
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How temperatures across the globe compared with normal during August 2016.
Credit: NASA
In what has become a common refrain this year, last month ranked as the hottest August on record, according to NASA data released Monday. Not only that, but the month tied July as the hottest month the world has seen in the last 136 years.
August came in at 1.76˚F (0.98˚C) above the average from 1951-1980, 0.16C above August 2014, the previous record holder. The record keeps 2016 on track to be the hottest year in the books by a fair margin.
That August continued the streak of record hot months this year and tied July as the hottest month was somewhat unexpected. The seasonal temperature cycle generally reaches a peak in July, as it did this year. But August was so anomalously warm — more so even than July — that it tied that month’s overall temperature.
It was also thought that July would likely be the last record hot month of the year, given the dissipation of El Niño.
Watch global temperatures rise over time, culminating in the streak of record hot months of 2016, including July and August, the two hottest months on record.
Credit: NASA Earth Observatory
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In NASA's dataset, August marks the 11th record-setting month in a row. That streak goes back 15 months through July in data from the National Oceanic and Atmospheric Administration. Each agency handles the global temperature data slightly differently and uses a different period of comparison, leading to slight differences in the monthly and yearly temperature numbers. Overall, though, both datasets show clear agreement in the overall warming trend.
That trend is what Gavin Schmidt, director of NASA's Goddard Institute for Space Studies, and other climate scientists emphasize. It is that excess heat that has accumulated over decades thanks to rising levels of greenhouse gases that accounts for the bulk of this year’s record warmth, with El Niño providing only a small boost.
"Monthly rankings, which vary by only a few hundredths of a degree, are inherently fragile," Schmidt said in a statement. "We stress that the long-term trends are the most important for understanding the ongoing changes that are affecting our planet."
International negotiators hope to curtail that long-term trend by limiting warming to less than 2˚C (3.6˚F) over pre-industrial levels by the end of the century. There have even been discussions to aim for an even more stringent target of 1.5˚C.
To show how close the world already is to surpassing that goal, Climate Central has been averaging the NASA and NOAA temperature data each month and comparing that number to the average from 1881-1910, closer to preindustrial times.
Through July, the global temperature for the year was 1.31˚C (2.36˚F) above the average from that period. A new average will be calculated through August when NOAA releases its temperature data on Sept. 20.
Whether September will continue the record streak is uncertain, but regardless of where it falls, there is already a greater than 99 percent chance that 2016 will take the title of hottest year, Schmidt has said.
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Obama Just Tied Climate Change to National Security
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An Israeli soldier stands on a Merkava tank on the Israeli-Syrian border near Quneitra on June 22, 2014. Research has shown that climate change-driven drought is linked to the Syrian Civil War and the current refugee crisis.
Credit: / Getty Images
On Wednesday (Sept. 21), President Obama took another step toward securing his climate legacy. This time his focus wasn't on energy, public lands or international diplomacy. It was on national security and making sure the U.S. military is prepared for a more unstable future.
The White House published a presidential memorandum setting up a timetable for more than 20 federal agencies to come up with a plan to put climate science into action when it comes to national security.
"It's not a new direction, but it is reinforcing and formalizing a direction in which the U.S. government was already headed," Sherri Goodman, a fellow at the nonpartisan Wilson Center, said. "That's how you turn concepts into action in the government. You have to have plans to get agencies to act."
Accompanying the memo was a report from National Intelligence Council outlining what some of the main climate threats will be to national security in the coming decades.
According to the national security-oriented blog New Security Beat, this the first unclassified report from the U.S. intelligence community that explicitly looks at the impact of climate change on national security. It indicates that climate change is not a distant future problem, but something that requires planning here and now. Specifically, the report said that "the effects resulting from changing trends in extreme weather events suggest that climate-related disruptions are under way."
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Examples of climate disruption are peppered throughout the report from how drought-induced food shortages in Mali led insurgent groups to start a "food for jihad" campaign, to how melting sea ice is raising tensions in the Arctic between Canada, Russia and other countries with a stake in the region.
Climate impacts have the power to destabilize the regions where they occur as well as places thousands of miles away. The Syrian civil war is the most notable example. Research has tied its start, in part, to a climate change-fueled drought that has sparked the greatest refugee crisis since World War II, according to Goodman. Other researchers were also quick to point out the chain of impacts the drought has had.
"Climate change has contributed to the emergence of civil war, refugee flows and other elements of instability," Marc Levy, the deputy director of the Center for International Earth Science Information Network, said. "But the follow-on impacts from climate-triggered instability extend worldwide, as seen in the European refugee crisis, which has strong connections to the Syrian conflict, which in turn has strong connections to climate stress."
Yet the present security concerns could pale in comparison to the future as the climate becomes more unstable. Sea level rise could swamp megacities in developing countries with fewer resources to cope, leading to a massive exodus of people, while water shortages could create more intense conflict, particularly in arid regions.
Even the infrastructure itself that supports the U.S. military faces challenges from climate change. A 2014 government report found that while the military is aware of the risks climate change poses to its 7,600 installations around the world, little action has been taken to address them because there's been no strong guidance.
The new Presidential Memorandum changes that by laying out a timeline for creating a plan and implementing it.
"The tools available for the military to plan for a more unstable world are woefully inadequate, because we have systematically underinvested in the development of such tools out of a combination of a failure of imagination to do what is needed and a failure of courage to stand up to the political opponents of meaningful climate change," Levy said. "What is so important about yesterday's Presidential decision is that it shakes free from those self-imposed shackles so that we can do what is needed."
The memo gives a host of federal agencies a mandate to work together to include climate change in their national security planning and a timeline of 90 days to create an action plan and 150 days to create a plan to implement it.
The implementation of any plans will fall squarely on the next administration. Hillary Clinton or Donald Trump could choose to go forward with the plan, restructure it or strike it down depending on their priorities. The latter would pose a major setback for the military, though, which will have to contend with more instability and the potential of major unknowns ahead.
"(This initiative) integrates government planning so we know where we are vulnerable and can act accordingly rather than waiting until disaster hits," Ruth Greenspan Bell, a security expert at the Wilson Center, said. "The essence of good defense is anticipating and acting on risk."
Original article on Climate Central.
Modern Alligator Looks a Lot Like Its 8-Million-Year-Old Cousin
Modern American alligatorscrawling around today in the swampy grounds of the Southeast U.S. don't look much different than their ancient ancestors did, recent research suggests.
The findings from fossils show that these scary creatures look pretty much the same as their ancestors did 8 million years ago. With the exception of sharks and a few other animal species, there are not many other living vertebrates that have changed as little as the gators have, the researchers said.
"If we could step back in time 8 million years, you'd basically see the same animal crawling around then as you would see today in the Southeast," study co-author Evan Whiting, a former undergraduate student at the University of Florida, said in a statement. "Even 30 million years ago, they didn't look much different." [Alligator Alley: Pictures of Monster Reptiles]
The American alligator has survived fluctuations in sea levels and the drastic changes in climate that have occurred in the Southeast over these last 8 million years. The changes would likely have caused less resilient animal species to go extinct, the researchers said.
During their studies, the researchers examined the skull of an ancient alligator unearthed in Florida, which was initially thought to be an extinct species. However, the researchers realized that the fossil's features were actually identical to the skull of the modern American alligator.
The researchers also looked at the composition of teeth that belonged to ancient alligators, and the teeth of extinct crocodiles. The presence of both the gator and croc fossils in several places in north Florida may mean that the two species lived next to each other many years ago in areas near Florida's coast, Whiting said.
However, based on their analysis of the teeth, the researchers concluded that the croc was a marine reptile, which went hunting for prey in the ocean, whereas the alligators typically went looking for snacks on land and in freshwater.
Despite being resilient to climatic changes in the distant past, modern alligators now face another threat that may prevent them from thriving: humans. For example, the reptiles were nearly hunted to extinction during the early 20th century, the researchers said.
Since then, special protections have been put in place that have helped to increase gator numbers in the wild, the researchers said. However, many alligator habitats are currently being destroyed because humans are moving into these areas, the researchers said. This in turn increases the chance of encounters between gators and humans, which can be deadly for either species.
"The same traits that allowed alligators to remain virtually the same through numerous environmental changes over millions of years can become a bit of a problem when they try to adapt to humans," Whiting said. "Their adaptive nature is why we have alligators in swimming pools or crawling around golf courses."
Originally published on Live Science.
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