Age of major dams in the United States. Data source: U.S. Army Corps of Engineers. Graphic: The New York Times

By Troy Griggs, Gregor Aisch, and Sarah Almukhtar
23 February 2017

(The New York Times) – After two weeks that saw evacuations near Oroville, Calif., and flooding in Elko County, Nev., America’s dams are showing their age.

Nearly 2,000 state-regulated high-hazard dams in the United States were listed as being in need of repair in 2015, according to the Association of State Dam Safety Officials. A dam is considered “high hazard” based on the potential for the loss of life as a result of failure.

By 2020, 70 percent of the dams in the United States will be more than 50 years old, according to the American Society of Civil Engineers.

“It’s not like an expiration date for your milk, but the components that make up that dam do have a lifespan.” said Mark Ogden, a project manager with the Association of State Dam Safety Officials. […]

Two weeks ago, heavy rains caused the Twentyone Mile Dam in Nevada to burst, resulting in flooding, damaged property and closed roads throughout the region. […]

Last week, 180,000 people downstream from Oroville Dam in California were evacuated after an emergency spillway showed signs of failing. [more]

America’s Aging Dams Are in Need of Repair

Aerial view of an iceberg calving from Pine Island glacier, 26 January 2017. Photo: NASA

By Chelsea Harvey
22 February 2017

(The Washington Post) – One of Antarctica’s most rapidly melting glaciers has shed yet another large block of ice in an event that NASA scientists say is “further evidence of the ice shelf’s fragility.” The agency drew attention to the incident in a tweet Wednesday morning. 

Pine Island Glacier, located on the edge of the increasingly unstable ice sheet of West Antarctica, is a top concern for climate scientists and one of the region’s biggest potential contributors to global sea level rise. It’s pouring about 50 billion tons of ice into the ocean each year, and scientists think this rate could continue to increase in the future. Altogether, the glacier has the potential to raise global sea levels by an estimated two feet.  

Scientists’ concern stems largely from the glacier’s interaction with the ocean, which laps against the exposed front of the floating ice shelf and also travels deep beneath it. Warming ocean waters can cause glaciers to melt from the bottom up, making them less stable and more likely to break. In fact, Pine Island Glacier has experienced several significant calving events — that’s when an iceberg breaks off from the ice shelf — in recent years. In 2015, the glacier lost a massive iceberg with an area of more than 200 square miles.  

The most recent event, which was captured via satellite imagery at the end of January, is small in comparison — NASA scientists estimate that the area of ice lost only spans a square mile or so. But the event speaks to the fact that the glacier is still melting and breaking.  

“I think this event is the calving equivalent of an ‘aftershock’ following the much bigger event,” said Ian Howat, a glaciologist at Ohio State University, in a recent statement. “Apparently, there are weaknesses in the ice shelf — just inland of the rift that caused the 2015 calving — that are resulting in these smaller breaks.” Indeed, scientists have previously observed multiple small rifts in the ice that they think could lead to more calving events in the future.

The incident comes as the future of the agency’s climate research grows increasingly uncertain. Last November, just after President Trump was elected, one of his campaign advisers shocked the climate science community by suggesting that the new administration should curtail NASA climate research activities.

And now, the issue has cropped up again in a hearing conducted last Thursday by the House Committee on Science, Space and Technology. At the hearing, committee chair Lamar Smith (R-Tex.) reportedly stated that he’d like to see a “rebalancing” at NASA, and later told E&E News that he’d like the agency to focus more on space exploration, while other agencies can focus on earth sciences and climate change. [more]

A huge Antarctic glacier just lost another chunk of ice — and we know because of NASA

(A) Spatial and temporal Ca2+ flux in ventricular cardiomyocytes from Pacific mackerel incubated for >30 min with phenanthrene (5 μM), fluorene (5 μM), dibenzothiophene (5 μM), carbazole (5 μM), naphthalene (5 μM), pyrene (5 μM), a DMSO control (1/1000) or untreated (control). Chemical formulae for each moiety are given in Supplementary Fig. S1. Shown here are representative raw confocal transverse line scans across the width of single myocytes loaded with the AM form of the calcium-sensitive dye (Fluo-4) (top) and the corresponding Ca2+ transient to indicate the inhibitory effects of individual PAHs on the temporal and spatial characteristics of Ca2+ dynamics (bottom). (B) Reduction in the mean amplitude of the Ca2+ transients expressed as peak fluorescence divided by baseline fluorescence (F/F0). (C) Increase in the time constant of Ca2+ transients decay (tau, time to decay to 37% of its peak). Data are means ± SEM of control (n = 39, N = 10), phenanthrene (n = 42, N = 4), fluorene (n = 21, N = 2), dibenzothiophene (n = 25, N = 3), carbazole (n = 21, N = 2), naphthalene (n = 28, N = 4), pyrene (n = 23, N = 2) and DMSO (n = 22, N = 5). Graphic: Brette, et al., 2017 / Nature Scientific Reports

16 February 2017 (The University of Manchester) – A study by Manchester and Stanford scientists into the effects on fish of a 2010 oil disaster could shed new light on how air pollution affects humans’ hearts.

The 2010 Deepwater Horizon disaster resulted in a major oil spill in the Gulf of Mexico, an area of water which is heavily populated with fish species. In a paper published in Nature Scientific Reports, the team analysed the effects of individual components of crude oil on the hearts of fish.

By studying cardiac cells from pelagic fish, like tunas and mackerels that live in the Gulf of Mexico, the team identified phenanthrene, a polycyclic aromatic hydrocarbon (PAH) released from oil as a key factor in disrupting heart function.

Furthermore the processes in the heart which are affected by this PAH are common across all vertebrates, including humans, and underlie both the strength and the rhythm of the heart.

This is of particular importance as phenanthrene is present in air pollution in urban areas.

Dr Holly Shiels, a senior lecturer at The University of Manchester who worked on the study, said: “These open ocean fish are hard to study in captivity, but understanding what component of the Deepwater Horizon disaster oil negatively affected the heart is really important. It could help us distinguish the cardiotoxic potential of environmental catastrophes.

“It also provides insight into the possible cardiac impacts of urban air pollution on public health.”

The use of oil and its derivatives, in particular in car engine combustion, has been a cause of concern for some time, with high levels of air pollutants measured in urban areas around the world, including in the UK.

Dr Shiels added: “Very little information to date has been available on individual PAH chemical toxicity beyond developmental and carcinogen effects. As a result we hope that this study will raise global interest in this important pollutant, given the prevalence of petroleum and PAHs in our environment.”

The paper, “A Novel Cardiotoxic Mechanism for a Pervasive Global Pollutant” was published in the journal Nature Scientific Reports. doi:10.1038/srep41476 It is available under open access.

For more information, visit the website of Dr Shiels' laboratory.

Contact

Jamie Brown, News and Media Relations Manager
jamie.brown@manchester.ac.uk
+44 (0)161 275 8383 / +44 (0)7887 561318

Fish affected by Deepwater Horizon spill give clues to air pollution heart disease


ABSTRACT: The Deepwater Horizon disaster drew global attention to the toxicity of crude oil and the potential for adverse health effects amongst marine life and spill responders in the northern Gulf of Mexico. The blowout released complex mixtures of polycyclic aromatic hydrocarbons (PAHs) into critical pelagic spawning habitats for tunas, billfishes, and other ecologically important top predators. Crude oil disrupts cardiac function and has been associated with heart malformations in developing fish. However, the precise identity of cardiotoxic PAHs, and the mechanisms underlying contractile dysfunction are not known. Here we show that phenanthrene, a PAH with a benzene 3-ring structure, is the key moiety disrupting the physiology of heart muscle cells. Phenanthrene is a ubiquitous pollutant in water and air, and the cellular targets for this compound are highly conserved across vertebrates. Our findings therefore suggest that phenanthrene may be a major worldwide cause of vertebrate cardiac dysfunction.

A Novel Cardiotoxic Mechanism for a Pervasive Global Pollutant

21 February 2017 (British Antarctic Survey) – Currently a huge iceberg, roughly the size of Norfolk, looks set to break off Larsen C Ice Shelf, which is more than twice the size of Wales. Satellite observations from February 2017 show the growing crack in the ice shelf which suggests that an iceberg with an area of more than 5,000 km² is likely to calve soon.

Researchers from the UK-based MIDAS project, led by Swansea University, have reported several rapid elongations of the crack in recent years. BAS scientists are involved in a long-running research programme to monitor ice shelves to understand the causes and implications of the rapid changes observed in the region. They shot this footage as they flew over the ice shelf on their way to collect science equipment.

During the current Antarctic field season, a glaciology research team has been on Larsen C using seismic techniques to survey the seafloor beneath the ice shelf.  Because a break up looks likely the team did not set up camp on the ice as usual.  Instead they made one-off trips by twin otter aircraft supported from the UK’s Rothera Research Station.

Ice shelves in normal situations produce an iceberg every few decades. There is not enough information to know whether the expected calving event on Larsen C is an effect of climate change or not, although there is good scientific evidence that climate change has caused thinning of the ice shelf. Once the iceberg has calved, the big question is whether Larsen C will start to retreat.

Aerial view of the Larsen C Ice Shelf crack in February 2017. Photo: British Antarctic Survey

Dr Paul Holland, ice and ocean modeller at British Antarctic Survey, says:

“Iceberg calving is a normal part of the glacier life cycle, and there is every chance that Larsen C will remain stable and this ice will regrow.  However, it is also possible that this iceberg calving will leave Larsen C in an unstable configuration.  If that happens, further iceberg calving could cause a retreat of Larsen C. We won’t be able to tell whether Larsen C is unstable until the iceberg has calved and we are able to understand the behaviour of the remaining ice.

“The stability of ice shelves is important because they resist the flow of the grounded ice inland.  After the collapse of Larsen B, its tributary glaciers accelerated, contributing to sea-level rise.”

About ice shelves

An ice shelf is a floating extension of land-based glaciers which flow into the ocean. Because they already float in the ocean, their melting does not directly contribute to sea-level rise. However, ice shelves act as buttresses holding back glaciers flowing down to the coast. Larsen A and B ice shelves, which were situated further north on the Antarctic Peninsula, collapsed in 1995 and 2002, respectively. This resulted in the dramatic acceleration of glaciers behind them, with larger volumes of ice entering the ocean and contributing to sea-level rise.

The largest icebergs known have all calved from ice shelves. In 1956, a huge iceberg of roughly 32,000 km² – bigger than Belgium – was spotted in the Ross Sea by a US Navy icebreaker. However, since there were no satellites in orbit at this point, its exact size was not verified. In 1986, a section of the Filchner ice shelf roughly the size of Wales calved – but this iceberg broke into three pieces almost immediately. The largest iceberg recorded by satellites calved from the Ross ice shelf in 2001, and was roughly the size of Jamaica at 11,000 km².

The MIDAS Project is funded by the NERC (Natural Environment Research Council).

New footage shows crack in Larsen C Ice Shelf

Aerial view of feral pigs in Texas. Photo: Eric Gay / AP Photo

By Andrea Lucia
21 February 2017

NORTH TEXAS (CBS News) – Announcing the “feral hog apocalypse” is within reach, Texas Agriculture Commissioner Sid Miller has approved of the first pesticide targeting wild pigs.

The move has upset hunters, who’ve gathered more than 1,200 signatures in opposition within two days.

“We don’t think poison is the way to go,” said Eydin Hansen, Vice President of the Texas Hog Hunters Association.

He prefers hunting and trapping methods to control the invasive species.

Hansen has been hunting hogs since he was 16.

“It’s a way to feed your family,” he said.

He worries soon he won’t want to take that risk.

“If this hog is poisoned, do I want to feed it to my family? I can tell you, I don’t.”

The approved poison, Kaput Feral Hog Lure, contains warfarin, the same drug used to kill rats or prescribed by doctors, in smaller doses, to prevent blood clots.

Hunters and conservationists are afraid other animals may be exposed to toxin.

“If a hog dies, what eats it? Coyotes, buzzards…” said Hansen. “We’re gonna affect possibly the whole ecosystem.” [more]

Fearing "feral hog apocalypse," Texas approves drastic measures

Antarctic ice mass balance changes from 1979 to 2016. Graphic: Eric Rignot

By Veronika Meduna
14 February 2017

(The Spinoff) – US-based glaciologist Eric Rignot is in New Zealand this week to talk about polar ice sheets and their potential to add to predicted sea level rise. He tells Veronika Meduna that it’s more important than ever to discuss climate science and what it’s like to be a climate scientist during the Trump presidency.

Eric Rignot is based at the University of California, Irvine, and NASA’s Jet Propulsion Laboratory, where he’s been tracking changes in ice mass in several glaciers in West Antarctica for two decades. He hit the headlines in 2014 when his research showed that the Amundsen Sea region in West Antarctica had entered an irreversible state of decline, with nothing to stop the glaciers in this area from melting into the sea.

The glaciers are particularly vulnerable because they are grounded below sea level, and they sit on sea bed topography that allows the warming ocean to slip in underneath and to melt them from below.

The Spinoff: So are these glaciers headed for total collapse?

Eric Rignot: I’d been studying that part of Antarctica since 1996, and in 2014, I came to the point … that we have learned enough and had looked at the system long enough and collected enough data to come to the conclusion that this part of Antarctica was in a state of irreversible retreat. This was the marine ice sheet instability people talked about in the 1970s, and it was right there in front of our eyes.

The key moment was really to get to the point where we’d mapped the bed topography in enough detail and don’t have questions marks anywhere in any of these troughs. They are all pretty much conducive to marine ice sheet instability. And the grounding line is retreating faster there than anywhere in the world.

After 14 years of observations you can say what’s happening there is big. It’s unique and it’s important. The message has to go out for people to know that there is enough scientific certainty to say that there is something very significant happening there. [more]

‘There’s a lot at stake here.’ US Antarctic expert Eric Rignot on climate science in the age of Trump

Insured losses from natural disasters, 2005-2015. Graphic: Crain's Detroit Business

By Michael Lee
19 February 2017

(Crain's Detroit Business) – Climate change presents a knotty problem — and big risks — for insurers.

Severe weather events such as hurricanes, tornadoes and droughts are expected to occur with more frequency as the climate warms up, experts say. That presents the risk of greater losses for insurers to cover damage claims.

There were 198 natural disasters worldwide in 2015, according to the most recent annual report by Swiss Re, the most it has ever recorded, though the $28 billion in losses stemming from them was relatively low for recent years because no hurricanes made landfall in the U.S.

Though politically controversial, the notion of climate change is not controversial among insurers. The industry is working to come to grips with how to measure the risks as scientists study the effects on a world in which the five warmest years in records dating to 1880 have all occurred since 2010.

At their core, insurers are in the business of measuring and assigning a value to risk. Precisely measuring the future risk of climate change is difficult because insurers base their pricing and risk assessments on historical data. A changing climate means that data could become of less use.

"Climate change can throw a wrench into the system by causing fundamental shifts in the location, frequency, and intensity of extreme events," said Eric Robinson, senior scientist at risk-management firm AIR Worldwide in Boston. [more]

Insurance industry grapples with potential losses from climate change

Members of the scientific community, environmental advocates, and supporters demonstrate on Sunday, 19 February 2017, in Boston, to call attention to what they say are the increasing threats to science and scientific research under the administration of President Trump. Signs bear slogans like, 'Make America Smart Again' and 'Science Not Silence'. Photo: Steven Senne / AP Photo 

By Patrick Reilly
20 February 2017

(The Christian Science Monitor) – As temperatures climbed above the 50 degrees F., on Sunday, many Bostonians enjoyed the February weekend outdoors on the city’s bike trails and waterfronts. But for those who gathered in Copley Square downtown, the unseasonable warmth was just the latest evidence of their cause for concern.

Climate change is not a controversy,” read one sign at yesterday’s “Rally to Stand Up for Science,” which drew hundreds to the historic downtown plaza. Other slogans were more lighthearted, arguing that “Trump’s team are like atoms – They make up everything.” 

Whether the signs provoked laughs or stoked outrage among onlookers, the rally’s attendees shared a sense of concern for the future of scientific research in the United States – particularly climate science – under President Trump. Sunday's protest added to the growing movement of scientists across the country who are voicing activist views on the Trump administration's emerging policies.

"We're really trying to send a message today to Mr. Trump that America runs on science, science is the backbone of our prosperity and progress," said Geoffrey Supran, a postdoctoral fellow at Harvard University and the Massachusetts Institute of Technology in Cambridge, who studies renewable energy, to the Associated Press.

This sentiment has spread after Trump, who once dismissed climate change as a “hoax,” won the presidential election in November. In the months that followed, Trump and his transition team have requested the names of Energy Department climate scientists, nominated fossil-fuel advocate Scott Pruitt to head the Environmental Protection Agency, and reduced that agency’s representation at a recent Alaska environmental conference. [more]

Science activism on the rise: Boston rally is latest iteration

By Lena H. Sun
20 February 2017

AUSTIN (The Washington Post) – The group of 40 people gathered at a popular burger and fish taco restaurant in San Antonio listened eagerly to the latest news about the anti-vaccine fight taking place in the Texas legislature.

Some mothers in the group had stopped immunizing their young children because of doubts about vaccine safety. Heads nodded as the woman giving the statehouse update warned that vaccine advocates wanted to “chip away” at parents’ right to choose. But she also had encouraging news.

“We have 30 champions in that statehouse,” boasted Jackie Schlegel, executive director of Texans for Vaccine Choice. “Last session, we had two.”

Now they also have one in the White House.

President Trump’s embrace of discredited theories linking vaccines to autism has energized the anti-vaccine movement. Once fringe, the movement is becoming more popular, raising doubts about basic childhood health care among politically and geographically diverse groups.

Public health experts warn that this growing movement is threatening one of the most successful medical innovations of modern times. Globally, vaccines prevent the deaths of about 2.5 million children every year, but deadly diseases such as measles and whooping cough still circulate in populations where enough people are unvaccinated.[…]

Personal-belief immunization exemptions increased from 2,314 in the 2003-2004 school year to 44,716 in 2015-2016. Graphic: Washington Post

The modern anti-vaccine movement is based on a fraud. A study published almost 20 years ago purported to show a link between childhood vaccines and autism. The data was later found to be falsified, and the study was retracted.

Scores of large-scale, long-term studies from around the world since then have proved that there is no connection between vaccines and autism. But the suspicion lingers. Its strongest form is a stubborn conspiracy theory that doctors, scientists, federal health agencies, vaccine-makers and the worldwide public health community are hiding the truth and are knowingly harming children. [more]

Trump energizes the anti-vaccine movement in Texas

 

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