Sunday, August 15, 2021

Protecting coral reefs more effectively from climate change

by University of Konstanz

AUGUST 13, 2021

Study sites and temperature tolerance thresholds of corals from the northern and central Red Sea. (a) Map of Red Sea sites, reefs are shown in red. Seven coral colonies of S. pistillata from each of one site in the Gulf of Aqaba (ICN), northern Red Sea, and three central Red Sea sites near each other (AF, ExT, PrT) were collected and examined for heat stress response patterns. (b) Photosynthetic efficiency (Fv/Fm) over temperature curves and determined ED50 thermal tolerance thresholds as a proxy for coral bleaching susceptibility (sensu Evensen et al., 2021) of corals from the ICN, AF, ExT, PrT reef sites. ED50 thermal tolerance thresholds are denoted as vertical bars with temperature values at the top of the respective bar in the respective site color. Solid lines in each curve reflect the mean three parameter log-logistic model fit for each population (n = 7 colonies) with 95% confidence intervals represented by the shaded areas. Statistical differences among sites are indicated by letters in the panel legend with site-specific MMM temperatures denoted thereafter. Symbols denote measurements from individual samples. Blue circles, coral samples from the Gulf of Aqaba ICN site; yellow triangles, coral samples from the central Red Sea AF site; pink squares, coral samples from the Central Red Sea ExT site; dark red diamonds, corals from the Central Red Sea PrT site. Credit: DOI: 10.1111/mec.16064

Thermally tolerant corals have different mechanisms for responding to heat stress. This is the conclusion of a current study by an international team of researchers including the Konstanz biologist Professor Christian Voolstra that was published in Molecular Ecology. The team examined responses to heat stress in the smooth cauliflower coral (Stylophora pistillata) in the Red Sea by combining the Coral Bleaching Automated Stress System (CBASS) – a mobile rapid heat stress test—with molecular analyses, in order to identify different types of thermal tolerance. The procedure is to be used worldwide, and the respective results could help provide corals with more targeted protection from the effects of climate change.

Death of corals worldwide caused by warming oceans

As a result of climate change, corals all over the world are currently dying. Within just a few decades, the global coral population has dropped by half, and, due to their locally adapted thermal tolerance, many corals are poorly prepared to respond to further increases in ocean temperatures. Some corals, however, are more adept at managing heat stress than others.

In order to elucidate the factors that contribute to higher thermal tolerance in corals, Voolstra and his colleagues introduced a new mobile testing system last year—the Coral Bleaching Automated Stress System (CBASS). The system makes it possible to quickly identify corals that are particularly resilient. "This test procedure is a small revolution for me, because it allows researchers and conservationists alike to assess coral resilience anywhere on Earth and to find out how endangered each coral reef is, without the need for costly and sophisticated tech", Voolstra described the CBASS system in a previous article.

Different thermal tolerance mechanisms

In the current study, the research team used the testing system to evaluate the thermal tolerance of the smooth cauliflower coral in different regions of the Red Sea. The results show that corals from the Gulf of Aqaba, the most northeastern arm of the Red Sea, demonstrate a remarkable thermal tolerance—up to about 7°C above the respective maximum monthly average for the warmest summer month—just like their peers from the central part of the Red Sea. However, the absolute thermal tolerance of smooth cauliflower corals from the central part of the Red Sea is up to 3°C higher than for the same species in the Gulf of Aqaba, which could suggest that different tolerance mechanisms are at work.

In order to investigate this possibility, the research team conducted molecular analyses to elucidate mechanisms of thermal tolerance in corals from the different locations. Genetic examinations showed that smooth cauliflower corals from the Gulf of Aqaba respond to heat stress with a strongly altered gene expression—for example the increased production of certain proteins. Parallel to this, the composition of the coral-associated bacterial communities changed. By comparison, corals from the central part of the Red Sea did not exhibit any of these changes when exposed to heat stress.

The molecular results support the idea that smooth cauliflower corals have different thermal tolerance mechanisms. "We interpret the response of the corals from the Gulf of Aqaba as that of a "resilient" population that directly and proportionally reacts to increases in temperature. By contrast, the more static expression of genes of the corals from the central part of the Red Sea indicates a fixed reaction norm, irrespective of the heat stress applied, which provides "resistance" to high water temperatures, but at the cost of the ability to flexibly respond to further increases in temperatures", says Voolstra.

Toolbox of methods for protecting coral reefs worldwide

At the moment, it is unclear which of these tolerance mechanisms protects corals better from the global increase in ocean temperatures caused by climate change. The fact that "resilient" and "resistant" tolerance mechanisms can be distinguished using molecular methods could be of great importance for the conservation prioritization of existing coral reefs or for restoration approaches that could use heat-tolerant corals for sexual propagation.

For this reason, the research team is making plans to employ the methodological approach used successfully in the Red Sea study around the world. "Our study shows the tremendous value of an integrative, combined approach: using the CBASS system for the standardized identification of thermal tolerance in corals with subsequent follow-up molecular analyses to identify the underlying tolerance mechanisms and marker genes", concludes Voolstra.

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Northern Red Sea corals live close to the threshold of resistance to cold temperatures
More information: Christian R. Voolstra et al, Contrasting heat stress response patterns of coral holobionts across the Red Sea suggest distinct mechanisms of thermal tolerance, Molecular Ecology (2021). DOI: 10.1111/mec.16064

Journal information: Molecular Ecology

Provided by University of Konstanz

Gorillas in our midst: DR Congo park fetes rare birth

A female eastern lowland gorilla in the Kahuzi-Biega National Park. The gorillas are one of the world's most endangered species — A female eastern lowland gorilla in the Kahuzi-Biega National Park.

DR Congo's Kahuzi-Biega National Park is celebrating the birth of an eastern lowland gorilla, one of the world's most endangered species

"We have the pleasure of announcing the birth of a baby to the female Mwinja," the park announced on Facebook on Friday.

"Our rangers were there and captured this moment of intimacy, on Saturday August 7. She seemed happy to be showing off her baby. Both are in very good healthy."

The birth is "a sign of hope," the park's spokesman, Hubert Mulongoy, told AFP.

The park, located in a deeply troubled part of eastern Democratic Republic of Congo, said the birth brought its tally of the apes—Gorilla beringei graueri—from 171 to 172.

Mwinja has already had offspring but this is the first she has had with a well-known male called Nabirembo.

The park's gorilla population includes two tribes who live in so-called habituation, meaning that they are used to human presence nearby.

Kahuzi-Biega covers around 6,000 square kilometres (2,300 square miles) of mountains and rainforests near the western banks of Lake Kivu and the Rwandan border.

It is a magnet for intrepid eco-tourists, who are drawn to its unique landscape and rare species.

The park is listed by UNESCO as a World Heritage site in danger because of the presence of armed groups and settlers, poaching and deforestation

Hope for critically endangered gorillas in eastern DRC

Carbon hidden in soil: Could Chesapeake Bay restoration methods be a model for blunting climate change?

by Katherine Hafner

Carbon dioxide — Ball-and-stick model of carbon dioxide. Credit: Wikipedia

For decades, farmers around the Chesapeake Bay have worked to limit the pollution going from their land into the water, as part of a program to restore the watershed.

But the measures taken to improve water quality have also had unforeseen side benefits for the climate, according to a new analysis from the Chesapeake Conservancy.

Nearly half a million tons of carbon dioxide were removed from Virginia's atmosphere in 2019 through agricultural conservation practices that weren't even intended for that purpose, the nonprofit found.

The findings could have implications for the battle against climate change, the study's authors say. They hope the Chesapeake Bay restoration efforts could serve as a model for another way to target greenhouse gasses.

The bay has long been a target for restoration. In the 1980s, nitrogen and phosphorus pollution was identified as the watershed's main threat.

Officials then formed the Chesapeake Bay Program, a large partnership between federal and state agencies, nonprofits, local governments and academic institutions focused on restoring the bay's health. It has since gone through many iterations.

In 2010, federal officials enacted a "pollution diet" for the bay that limits the nutrients and sediments that can enter the bay. When too much nitrogen and phosphorus—which are found in fertilizers—get in the bay, they can lead to excessive algae that suck up oxygen and block sunlight for underwater plants.

The main way that conservation practices are enacted on farms is through a federal program that gives out money for doing so, said Susan Minnemeyer, vice president of conservation technology at the Chesapeake Conservancy and an author of the recent report.

A farmer can receive money per acre of land on which they implement the practices. It's a way to generate additional income from their fields and some of the practices also increase a farm's productivity, she said.

The practices include silvopasture—adding more trees to land where livestock grazes—better managing the nutrients in fertilizer and setting up cover crops including wheat and rye that improve the soil.

The conservancy, a partner in the Chesapeake Bay Program, got interested in looking at the fringe carbon benefits of the agricultural tactics because local scientists had discussed but never explicitly analyzed them, said Joel Dunn, the nonprofit's president and CEO.

"Our gut told us all these water quality land management practices were actually having a very positive carbon sequestration impact," Dunn said.

Carbon sequestration is the term for when carbon dioxide is captured from the atmosphere and stored elsewhere. When it comes to agriculture, that means in the soil.

It's become an increasingly prominent topic of conversation among political and environmental leaders who argue removing existing carbon will be an important tool in the arsenal against climate change.

In 2019, the group found, about 459,639 tons of carbon dioxide were removed from the atmosphere through agricultural conservation practices.

That's roughly equivalent to about 0.4% of Virginia's energy emissions from the year before, or about the electricity needed to power more than 50,000 homes for a year.

Most effective for removing carbon? Putting up trees and other vegetation, which pull carbon dioxide out of the air.

The way farmers do that can mean adding trees to areas where livestock graze—which also reduces erosion and provides shade for animals—or planting trees and vegetation lined up along a waterway. The shrubbery also captures fertilizer runoff that could otherwise cause algal blooms in the bay, Minnemeyer said.

Though trees grabbed the most carbon per acre, the study found that soil-focused methods stored the most total, because of the sheer amount of agricultural land across the commonwealth.

That includes planting cover crops and reducing how much a farm's soil is churned up through mechanical digging and overturning. The less the soil is disturbed, the more carbon-rich organic matter it holds, Minnemeyer said.

"You're keeping carbon out of the atmosphere by holding it in the soil," she said.

The organization's leaders hope the report can jumpstart more investment in these methods—not just from the government but from private capital firms interested in promoting sustainability. They'd also like to see increased payments to farmers for implementing the practices, and for more private landowners to get involved on their own properties.

Meanwhile, Virginia's government recently conducted its own analysis and found that the bay restoration efforts since 2009 have resulted in the storing of about 460,000 tons of carbon dioxide per year, almost exactly what the conservancy estimated.

State officials expect that figure to grow to more than 2 million per year by 2025.

Dunn, the conservancy's president, said the analysis takes on added importance in light of a jarring international report this week stating that climate change is a "code red for humanity" and that the world only has a few decades left to stop the worst effects of warming.

The millions of tons of carbon removed so far in Virginia happened purely as a side benefit, Minnemeyer noted. Imagine the potential impact, she said, if we actually went all in on the strategy.

Senate OKs bill to certify farm practices limiting emissions

Turning off the genes that allow invasive mussels to spread and survive

by Morgan Greene

In Lake Michigan, mussels face divers ready to scrape them off rocks, molluscicides pumped underwater capable of tearing apart their digestive systems, another invasive species hungry for their young and any number of death traps researchers dream up next.

Throughout the country, scientists are studying a range of control methods to uproot invasive mussels, hoping that—like the threads that glue the mollusks down—something eventually sticks.

Zebra and quagga mussels hitched a ride into the Great Lakes from Eastern European seas three decades ago, filtering and blanketing their way across much of the freshwater haven, settling down as far away as California.

The search for solutions involves weighing the effect a treatment is likely to have on the mussels with the effect it may have on everything else in an ecosystem. Chemicals have been proven to kill mussels but can also be toxic to native mussels—many of which are already threatened or endangered. Some control methods may work for clearing mussels from a fixed structure but struggle to stand up against the unpredictability of open water. Or else end up being prohibitively expensive.

Now scientists are studying methods of genetic control—an approach that could spare other organisms from becoming collateral damage and potentially solve the scale problem.

"It could provide a way to do what we can't do now, which is to treat an infested body of water," said Scott Ballantyne, a biology professor at University of Wisconsin River Falls who is part of the team that started researching RNA interference and zebra mussels this year. "So that's the hope."

RNA can act as a translator, helping convert the information stored in a cell's DNA into proteins essential to the body's function. RNAi—RNA interference—can essentially block that process and "turn off" a gene.

The revelatory discovery happened by accident after a number of oddities, including an effort to make an especially vibrant petunia. Instead, scientists ended up with white petals—and an enigma.

Turns out, the scientists set off a naturally occurring regulatory mechanism using double-stranded RNA. Normally, RNA in a cell is single-stranded, but many viral genomes are double-stranded. The interference may have developed in response to these foreign appearances.

The discovery has led to treatment for a rare genetic disease in humans—and could potentially be used to treat a range of serious conditions.

RNAi research, which involved injecting double-stranded RNA in the nematode worm, won scientists a 2006 Nobel Prize.

"We probably know more about that little worm than any other living thing on the planet," Ballantyne said.

The work has become personal to Ballantyne—mussels were found in the Wisconsin lake where he and his wife have a cabin.

"I thought, surely in 30-plus years of looking at these mussels, we would have better tools to manipulate their DNA," Ballantyne said. "I was kind of aghast at how little we could do with them compared to a lot of other creatures."

The mussels, nearly impossible to eliminate in open water, are tough to keep alive in a lab, he said.

"We struggle even now to keep them happy and healthy for a few weeks in our lab," Ballantyne said. "In the wild they just thrive."

Daryl Gohl, group leader of the University of Minnesota Genomics Center Innovation Lab, was among the researchers who sequenced the genome of the zebra mussel, published in 2019, and is now working on the RNAi project.

Using an RNAi strategy directly for biocontrol with zebra mussels is still a bit of a moonshot, Gohl said.

"Then there are also the political and social considerations, whether it would make sense to deploy something like this in the wild," Gohl said.

But, with the zebra mussel genome, which includes a map and catalog of its genes, researchers can home in on genes connected to the processes that allow the mussels to spread and survive, including the formation of shells or the threads the mussels use to attach to surfaces.

"We have this list of potential targets that one could exploit to potentially enable some sort of biocontrol down the road," Gohl said.

Genetic control strategies could also combine and supplement more traditional control approaches. Scientists are targeting genes they predict are involved in stress responses—including tolerating heat, or toxins such as copper sulfate.

Researchers could potentially engineer a food source like bacteria, or algae, which would introduce the double-stranded RNA to the mussels, Gohl said. The material could even be distributed to the mussels similarly to Zequanox engineering, which involved a frame and tarp system to pump the molluscicide underwater. For lab tests, they could directly inject the mussels.

While RNAi research is underway on zebra mussels, other scientists are considering a different approach with quagga mussels.

CRISPR is another genetic technology that is most commonly used to directly edit DNA, and can mean a permanent change passed on through generations, unlike the more indirect RNAi.

Researchers with the federal Bureau of Reclamation, which oversees water management, have a draft genome of the quagga mussel and are investigating CRISPR technology for future biocontrol.

Biologist Yale Passamaneck is working on the project and analogized sequencing the genome to "the world's most complex jigsaw puzzle."

Now, Passamaneck said, researchers have "a book in a foreign language and you need to be able to decipher it."

Scientists are working on that translation dictionary.

"You can't really think about a genetic biocontrol project with any seriousness until you have a really high quality genome—and a good annotation of it," Passamaneck said.

Researchers are interested in targeting reproduction in the quagga mussel, Passamaneck said.

But while there's information about the mussels' ecology, their impacts on infrastructure and how to control them in dams, when it comes to genetic research, "there's still a pretty big knowledge gap," he said. For example, scientists still don't know how sex determination happens in the mussels.

Figuring out how CRISPR could be implemented in mussels is a challenge, he said, because of how little is known about the mussels compared with many other organisms. But, if the technology could be implemented, it could solve how to control mussels in large bodies of water—an exciting prospect to scientists, Passamaneck said.

With quagga mussels, you're "reinventing the wheel" to an extent, Passamaneck said. "You can take the whole bag of tricks that's available, but then you have to figure out which ones work and which ones don't."

As for the most promising solution, Passamaneck said it may take a collection of different approaches.

"It's going to take a lot of work by a lot of people to get there," he said.

Quagga mussel found to be primary regulator of phosphorus cycling in lower four Great Lakes

New evidence about Roman Britain executions revealed

by King's College London

Thrown to the Lions? New evidence from Roman Britain executions revealed — Credit: University of Leicester Archaeological Services

King's research has helped uncover new evidence showing the portrayal of the execution of captives in the arena by throwing them to lions. The evidence follows the discovery of an elaborately-decorated Roman bronze key handle.

The handle, discovered by archaeologists in Leicester, portrays a "Barbarian" grappling with a lion, together with four naked youths cowering in terror.

The key handle was discovered by University of Leicester Archaeological Services (ULAS), buried below the floor of a late Roman town house excavated in the city in 2016. After conservation, this unique object was studied at King's and the findings are now published in the journal Britannia.

Dr. John Pearce, Senior Lecturer in Archaeology, (Classics), is a co-author of the study, and helped decipher the key handle.

Dr. Gavin Speed, who led the excavations at a site off Great Central Street in Leicester, is a co-author on the study and described the moment the find was made. He said, "When first found, it appeared as an indistinguishable bronze object, but after we carefully cleaned off the soil remarkably we revealed several small faces looking back at us, it was absolutely astounding. Nothing quite like this has been discovered anywhere in the Roman Empire before."

Roman law sanctioned the execution of criminals and prisoners of war in the arena through the public spectacle of throwing them to the beasts; defined by the Latin term damnatio ad bestias.

This form of execution was often used to symbolize the destruction of Rome's enemies; members of those tribes who lived outside the Roman Empire and were collectively known as "Barbarians."

The main figure portrayed on the handle displays many of the features associated with such "Barbarians"' including mane-like hair, a bushy beard, bulging eyes, and the wearing of trousers below a naked torso. The lion is wrapped around his body and bites the side of his head. Beneath the struggle, four naked youths stare outwards; the older two appearing to protect their younger compatriots, one of whom may hold a stone. The youths are thought to symbolize the "children of the tribe" and their imminent demise demonstrates what happens when Roman conquest is opposed.

Direct evidence for violent spectacles in Roman Britain is otherwise extraordinarily scarce, a rare exception being the puncture wound inflicted by a large carnivore on the pelvis of a male skeleton from Roman York.

Archaeologists believe the key was probably made a century or more after Britain itself had been conquered, and it is interesting to reflect on the idea that those whose recent ancestors were themselves considered Barbarians, now shared in the Roman contempt and fear of those who remained outside the Empire.

Many Roman towns in Britain possessed either an amphitheater or a theater, where such spectacles could have been witnessed by large crowds. The town house where the key handle was found stands next door to the newly-discovered Roman theater in Leicester, and it is tempting to think that life did indeed imitate art and that the holders of the key had witnessed such scenes at close quarters.

Lions are portrayed on other key handles from Roman Britain and probably symbolized security and the protection of the household. This sense of security extended beyond the life of the key as a functional object, as the detached handle clearly continued to be valued. It was placed upright in the makeup of a new floor laid long after the heyday of the opulent house it had once secured, in the hope that it would still offer protection.

ULAS post-excavation manager and co-author, Nick Cooper, added that the key handle was one of the most significant finds from Roman Leicester and would be displayed to the public at Jewry Wall Museum in Leicester, following completion of major refurbishment work expected to be completed by 2023.Dutch unearth Roman canal, road near UNESCO heritage sites

More information: Pearce, J., Speed, G., & Cooper, N. (2021). At Death's Door: A Scene of Damnatio ad Bestias on a Key Handle from Leicester. Britannia, 1-16. DOI: 10.1017/S0068113X21000118

Provided by King's College London

Wildfires ravage vast area of eastern Bolivia: NGO

Firefighters battle flames close to the Santa Cruz airport in Bolivia on August 1, 2021.

Devastating wildfires in Bolivia consumed 749,000 hectares from January to July, the Friends of Nature Foundation (FAN) NGO said on Thursday night

FAN said it had used images from the European Space Agency's Sentinel-2 satellite to study the damage.

As in neighboring Brazil, the fires have been aggravated by widespread deforestation aimed at expanding farming or pastureland.

The eastern Santa Cruz and northeastern Beni departments account for 94 percent of burnt areas, FAN said.

Up to the end of July, 137,000 hectares (3400,000 acres) had been burnt in Santa Cruz but the local governor said Thursday that figure had since passed 200,000.

Beni had registered 564,000 hectares of damage in the seven-month period.

Santa Cruz, which lies close to the border with Brazil, declared a "red alert" on Thursday.

"The red alert was declared because of the progressive increase in heat sources and because of the climactic conditions we're facing," said Yovenka Rosado, the coordinator for forest fires in Santa Cruz.

According to the FAN report, the vast majority of the burnt area was pastureland, shrubs and grasslands.

Just three percent was woodland while eight percent was land used for farming.

FAN estimates that more than 2.3 million hectares of forests and prairies were destroyed by fire in 2020 and 6.4 million hectares the year before.

Forest fires in Bolivia consume vast area: official

Northwest heat wave and bad air from wildfires pose danger

by Gillian Flaccus

Chad Messenger collects cooling supplies including bottled water donated by the Cascadia Behavioral Healthcare's street outreach team on Thursday, Aug. 12, 2021, in Portland, Ore. Credit: AP Photo/Nathan Howard

Temperatures were expected to soar to triple digits again Friday in Portland, Oregon, and Seattle as a heat wave bakes the Pacific Northwest, and forecasters said hot weather and wildfire smoke would pose a problem through the weekend.

An air quality alert was issued through Saturday night for much northwestern Washington because of smoke drifting in from blazes in British Columbia and eastern Washington. However, forecasters said the hazy sky could drop temperatures slightly lower than predicted Friday and Saturday.

Temperatures reached 103 F (39 C) on Thursday in Portland and the 90s in Seattle. In Bellingham, Washington, the high hit 100 F (38 C) for the first time on record. It's the second major heat wave in less than a month in a normally temperate region where many don't have air conditioning. Record-breaking hot weather in late June caused hundreds of deaths in Washington state, Oregon and British Columbia when the thermometer went as high as 116 F (47 C).

A detailed scientific analysis found the June heat was virtually impossible without human-caused climate change. Meteorologist Jeff Masters with Yale Climate Connections said a similar study would need to be done with other heat waves, but there's a general link between global warming and worsening heat waves.

Scott Zalitis carries freezer pops and water provided by Cascadia Behavioral Healthcare's street outreach team on Thursday, Aug. 12, 2021, in Portland, Ore. People have headed to cooling centers as the Pacific Northwest began sweltering under another major, multiday heat wave. Credit: AP Photo/Nathan Howard

"If you increase your baseline temperature, you great increase your odds of extreme heat events," said Masters, co-founder of the private Weather Underground company.

Much of the Northwest was under an excessive heat warning through Saturday. The National Weather Service said heat advisories and warnings were also in effect from the Midwest to the Northeast and mid-Atlantic through at least Friday.

Oregon Gov. Kate Brown has declared a state of emergency and activated an emergency operations center. City and county governments have opened cooling centers, extended public library hours and waived bus fare for those headed to cooling centers. A 24-hour statewide help line will direct callers to the nearest cooling shelter and offer safety tips.

Authorities scrambled to provide relief to the vulnerable, including low-income older people and those living outdoors. Oregon volunteers handed out water, portable fans, popsicles and information about cooling shelters to homeless people living in encampments along the Columbia River on the outskirts of Portland.

A fan at T-Mobile Park keeps cool with a portable fan during a sunny day baseball game between the Seattle Mariners and the Texas Rangers, Thursday, Aug. 12, 2021, in Seattle. The usually temperate Pacific Northwest region entered the peak days of a scorching heat wave Thursday. Credit: AP Photo/Ted S. Warren

Darlene McApline, an administrative coordinator with Cascadia Behavioral Healthcare's street outreach team, dumps a bottle of water on her head to cool off while loading supplies on Thursday, Aug. 12, 2021, in Portland, Ore. Credit: AP Photo/Nathan Howard

Katherine Morgan wipes sweat from her forehead while walking to work in high temperatures on Thursday, Aug. 12, 2021, in Portland, Ore. People have headed to cooling centers as the Pacific Northwest began sweltering under another major, multiday heat wave. Credit: AP Photo/Nathan Howard

Vivek Shandas, a professor of climate adaptation at Portland State University, takes a temperature reading of almost 106 degrees in downtown Thursday, Aug. 12, 2021, in Portland, Ore. People have headed to cooling centers as the Pacific Northwest began sweltering under another major, multiday heat wave. Credit: AP Photo/Nathan Howard

Chris Cowan with Cascadia Behavioral Healthcare's street outreach team loads water and other cooling supplies before visiting homeless camps on Thursday, Aug. 12, 2021, in Portland, Ore. Credit: AP Photo/Nathan Howard

A woman living along the Columbia River who declined to be named, drinks a bottle of water delivered by Cascadia Behavioral Healthcare's street outreach team on Thursday, Aug. 12, 2021, in Portland, Ore. Credit: AP Photo/Nathan Howard

Katherine Morgan drinks water in front of a box fan while trying to stay cool in her downtown apartment without air conditioning on Thursday, Aug. 12, 2021, in Portland, Ore. People have headed to cooling centers as the Pacific Northwest began sweltering under another major, multiday heat wave. Credit: AP Photo/Nathan Howard

Cascadia Behavioral Healthcare's street outreach team loads water and other cooling supplies before visiting homeless camps on Thursday, Aug. 12, 2021, in Portland, Ore. Credit: AP Photo/Nathan Howard

A fan at T-Mobile Park adjusts a cloth on his head during a sunny day baseball game between the Seattle Mariners and the Texas Rangers, Thursday, Aug. 12, 2021, in Seattle. The usually temperate Pacific Northwest region entered the peak days of a scorching heat wave Thursday. Credit: AP Photo/Ted S. Warren

People experiencing homelessness are often reluctant to go to cooling centers, said Kim James, director of homeless and housing support for Cascadia Behavioral Healthcare, a nonprofit group that serves the homeless and those with mental illness.

Scott Zalitis, who was shirtless in the heat, ate lime-green popsicles handed out by the group Thursday and told volunteers that the temperature at his campsite reached 105 F (41 C) the day before.

"It's miserable. I can't handle the heat no matter what. So, I mean, it's hard to stand. Even in the shade it's too hot," Zalitis said. "You want to stay somewhere that's cool, as cool as possible."

The encampment, where rusted-out cars and broken-down RVs mixed with tents and piles of garbage, was in sharp contrast to downtown Portland, where sweaty pedestrians cooled off by running through a large public fountain in a riverfront park.

Explore further Northwest sizzles as heat wave hits many parts of US

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Crop insurance and unintended consequences

by North Carolina State University

A new study suggests that crop insurance serves as a disincentive for farmers to adopt climate change mitigation measures on their croplands.

The study by researchers at North Carolina State University examined the interactions of warmer temperatures, crop yield risk and crop insurance participation by farmers. For the study, researchers developed models using historical county-level corn and soybean production data in the United States, with an eye toward understanding the production impacts of rising temperatures.

The researchers found that variation in crop yields due to higher temperatures rose when more farmers had crop insurance. Interestingly, the results showed greater variability effects for corn yields than for soybean yields.

"This could be an unintended consequence of providing subsidies for crop insurance," said Rod M. Rejesus, professor of agricultural and resource economics at NC State and the corresponding author of the research study. "The concept of moral hazard could be present here. If insurance will cover crop losses due to various effects like drought or severe weather, a farmer may not want to pay the extra expense for climate change adaptation efforts such as using cover crops to improve soil health, for example."

Climate change—including warmer temperatures—increases the variability of crop yields; farming becomes a riskier proposition as this variability rises.

The study models indicate that an increase of daily minimum and maximum temperatures of 1 degree Celsius would increase county-level corn yield variability by 8.6 bushels per acre if 80% of farmers in a county have crop insurance. The same temperature rise in a county with 10% crop insurance participation would increase corn yield variability by just 6.2 bushels per acre.

The researchers pose possible solutions to this quandary for policymakers. They include providing more subsidies to encourage farmers' use of climate change mitigation efforts—like soil health practices—and starting high-level policy conversations about how to possibly tweak rules and guidelines that govern crop insurance contracts in order to reduce the disincentive effects.

Rejesus will continue to study the effects of climate change, crop yields and crop insurance, including the role of certain climate mitigation efforts by farmers.

The paper appears in the European Review of Agricultural Economics. Former NC State Ph.D. student Ruixue Wang is the paper's first author. NC State postdoctoral researcher Serkan Aglassan also co-authored paper.US corn and soybean maladapted to climate variations, study shows

More information: Ruixue Wang et al, Warming Temperatures, Yield Risk and Crop Insurance Participation, European Review of Agricultural Economics (2021). DOI: 10.1093/erae/jbab034

Provided by North Carolina State University

Men, Conservative Party supporters and Brexit-backers more likely to support the use of nuclear weapons, study shows

by University of Exeter

Men, Conservative Party supporters and those who wanted Britain to leave the EU, are more likely to want to retain Britain's nuclear deterrent, a study shows.

Those who endorse superior military power worldwide as an important foreign policy goal and people who want to protect the transatlantic relationship are also more likely to be in favour of nuclear weapons, according to the research.

Those who voted 'remain' in the EU referendum are less likely to support keeping nuclear weapons relative to those who voted to leave the EU. Supporters of Labour, the Liberal Democrats, the SNP, UKIP, the Green Party, and Plaid Cymru are less likely to support keeping nuclear weapons.

The study, published in the European Journal of International Security, was carried out by Ben Clements, from the University of Leicester, and Catarina Thomson, from the University of Exeter.

Academics used data from the new UK Security Survey to analyse attitudes towards the possession of nuclear weapons among the British public, the majority of who supported retaining nuclear weapons.

Dr. Thomson said: "We have found the recurring 'gender gap' found on state use of conventional military force extends to Britain's nuclear force capabilities, with men more in favour of retaining the nuclear deterrent than women.

"Political preferences have a significant role to play in affecting people's likelihood of supporting of Britain retaining its nuclear weapons. Identifying with political parties with a clear nuclear stance is generally significant in affecting people's views on the UK nuclear programme.

"Our data suggest that supporters of parties that do not take an anti-nuclear stance, such as the Liberal Democrats or UKIP, are less likely to support keeping nuclear weapons. Those who voted for Britain to remain in the EU are less likely to agree with the statement that the UK should keep its nuclear weapons. This provides further evidence of the potency of views on the Brexit debate for other issues in the post-referendum political landscape, concerning both domestic and external policy."

Dr. Clements said: "Views on nuclear weapons are clearly underpinned by attitudes towards core foreign policy debates relating to Britain's international role and relationships. Those who consider it is important for Britain to maintain a superior military power worldwide are more likely to agree that the country should retain its nuclear weapons compared to those who do not hold these views.

"It seems people perceive the nuclear dimension of US-UK bilateral relations to be particularly important to the overall stability of the broader 'special relationship' and to be particularly beneficial for Britain's defence capabilities. This may be because so few countries in Europe possess nuclear weapons—just Britain and France—so such capabilities are seen as less relevant or even undesirable for those who support security cooperation with the continent."

The survey was fielded by YouGov between 1– 25 April 2017 (before the official announcement of the snap general election), with a representative sample of 2,002 adults in Britain. The data was weighed by age, gender, social class, region, level of education, how respondents voted at the previous election, how respondents voted at the EU referendum, and their general level of political interest

Can we track the world's nuclear weapons?

More information: Ben Clements et al, The 'ultimate insurance' or an 'irrelevance' for national security needs? Partisanship, foreign policy attitudes, and the gender gap in British public opinion towards nuclear weapons, European Journal of International Security (2021). DOI: 10.1017/eis.2021.17

Provided by University of Exeter

NREL's thermoplastic blade research dives deep with verdant power's tidal energy turbines

by National Renewable Energy Laboratory

National Renewable Energy Laboratory (NREL) researchers have been exploring the use of thermoplastic composite materials for wind turbines for several years, but they have only just begun to scrape the surface of how these materials perform underwater. For the first time in history, thermoplastic composite blades, which have the potential to revolutionize the marine energy industry, are being tested on a large-scale tidal power turbine.

Previous laboratory-scale research performed at Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) demonstrated how thermoplastic materials can improve fatigue performance, decreasing the probability for catastrophic blade failures and making tidal turbine blades more sustainable for marine energy applications. The manufacturing process is also faster and more energy efficient. Additionally, thermoplastics, which make up about 75% of worldwide plastic production, can be recycled because the plastic polymer material can be remolded at high temperatures and resolidifies upon cooling.

Thanks to funding from the U.S. Department of Energy's Water Power Technologies Office and a collaboration with Verdant Power, NREL researchers have constructed turbine blades using thermoplastic composite materials and are now testing them on one of Verdant Power's tidal turbines, which are currently deployed in New York City's East River.

Evaluation of the loads and performance of the turbines at the Roosevelt Island Tidal Energy (RITE) project site in New York began in October 2020 with the installation of Verdant Power's TriFrame mount, which holds three tidal turbines. Because of strong tidal currents that change direction multiple times per day, the East River is an ideal location for testing and validating the performance of marine energy turbines. Both the TriFrame and three-bladed turbines were designed to be modular and scalable, allowing researchers to study the 5-meter (m)-diameter turbines and then scale them up to the more economically viable 10- to 15-m-class turbine systems that are more likely to be used in the field.

During their first 6 months in the water, the tidal turbines, whichinitially had epoxy blades, generated almost 200 megawatt-hours of energy—a U.S. record for marine energy production. After a 6-month deployment, in May 2021, the Verdant Power team performed a retrieve-and-replace (R&R) operation, swapping out one of the epoxy-bladed rotors with a new, NREL-manufactured rotor with thermoplastic blades that are identical to the original epoxy blades except for their material.

"Verdant Power provided the NREL team with the blade tooling and geometry details so we could produce thermoplastic blades that are identical to the epoxy blades that they've already manufactured, which allows us to do a side-by-side comparison with traditional materials," Murray said. "We're really interested in using these thermoplastic materials because they could potentially prolong the life of the blades and have improved structural properties for marine applications.

For several months prior to the R&R deployment, NREL Research Engineer Robynne Murray and her team have been tapping into the manufacturing and materials characterization capabilities at NREL's Composites Manufacturing Education and Technology (CoMET) facility. There, they built the 2.5-m blades using a vacuum infusion method with Elium thermoplastic resin. They then worked to confirm that these blades had similar structural performance to the traditional epoxy resin blades prior to deployment, structurally validating the full-scale, thermoplastic, tidal power turbine blades that are now generating power in the East River. After its trial run ends and the blades are retrieved by the end of 2021, the team will measure the blades' structural response to applied loads to quantify the impact of seawater on these materials.

An NREL-built data acquisition system sits inside the tail cone of the newly installed tidal turbine, allowing researchers to measure the strain and angular position of the thermoplastic blades while in action in the East River. The data acquisition system design and validation process, which included submerging the system in water for several days, meets several requirements, including the ability to continuously and reliably acquire, measure, and store all the data generated during the turbine's entire deployment period—estimated to be up to 28 gigabytes.

"This work will demonstrate a potentially game-changing material for marine applications at a meaningful scale," Murray said. "It will also produce strain and acceleration data for full-scale turbines that we can use to validate design tools and derisk future deployments, industrywide. The collaboration with Verdant Power and the ability to join their innovative R&R operation has been key to obtaining these data that will benefit the marine energy industry for years to come."

Since the May 2021 R&R, NREL's tidal turbine has been producing power for New York City's electric grid and even experienced some of the highest loads the blades will see during the deployment. That data will be particularly useful in examining how these turbines perform during the most extreme conditions, adding key information to the growing understanding of operational turbine limits and saturated thermoplastic materials and their promise to resolve tomorrow's marine energy challenges.

This summer, the Pacific Northwest National Laboratory will be performing a survey of the TriFrame's flow speeds at the RITE Project site to obtain flow data for the operational tidal turbines. These data will be used to validate flow velocity models, which will be publicly accessible to the marine energy industry.

Until its deployment ends, the NREL team watches and waits while their thermoplastic blades help generate tidal energy at scale for the first time

NREL advanced manufacturing research moves wind turbine blades toward recyclability

Provided by National Renewable Energy Laboratory

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