Tuesday, October 26, 2021

Eureka! A cost effective and quick way to find groundwater in arid regions


Peer-Reviewed Publication

UNIVERSITY OF SOUTH AUSTRALIA

Water is a scarce commodity in many countries worldwide, but new cost-effective technology pioneered by researchers in Australia, Egypt and Saudi Arabia could ensure sustainable water supplies for decades to come.

University of South Australia researcher Dr Alaa Ahmed and colleagues from the Desert Research Centre in Egypt, and King Abdulaziz City for Science and Technology in Saudi Arabia, have used the iconic Flinders Ranges to demonstrate how precious groundwater can be found without expensive drilling.

Using satellite imagery, geospatial techniques and adding information on drainage, rock types, fractures, topography and rainfall, Dr Ahmed has mapped the Hawker region in the Flinders Ranges into three distinct classifications for groundwater stored in fractured rock aquifers: good, moderate and low.

His study indicates that the most effective groundwater recharge zones (where surface water collects as it moves downwards) are located where there are numerous rock fractures, low drainage and a gentle slope.

Conversely, the least effective areas to find groundwater are underlain by shale and siltstone.

“The remote sensing doesn’t cost us anything because existing satellites located above Australia are already taking photos of the topography. We also have the software – GIS – to analyse and map all the data,” Dr Ahmed says.

Existing methods to assess groundwater sources involve extensive drilling, which is expensive, time consuming and often inaccurate.

Using a combination of remote sensing, GIS and information and other geological factors, hydrologists should be able to find precise groundwater locations at a fraction of the cost, he says.

“Groundwater makes up approximately 17 per cent of Australia’s available water resources, 30 per cent of its consumption and is found across 60 per cent of the continent.

“But prolonged droughts have led to higher salinity and pumping costs and fewer groundwater sites.

“We urgently need to find faster and cheaper ways to locate groundwater because water supplies are limited in so many parts of the country. By creating satellite maps showing where groundwater is more likely to be found, we can go a long way towards improving our water resources,” he says.

Groundwater is the main source of fresh water in the Flinders Ranges and is affected by the type, thickness and structural fabric of the underlying rocks, erosion, topography, drainage and the climate.

While the central Flinders Ranges lies north of Goyder’s Line, deemed unsuitable for cropping, sheep and cattle farming still needs a reliable source of water, as do the townships of Hawker and Parachilna.

Both towns are reliant on groundwater from fractured rock aquifers for their water supply and are dependent on limited production wells.

While this study was undertaken in South Australia, the same technique could be used to detect groundwater in any arid region across the world, including Egypt, where Dr Ahmed has carried out similar research.

“Water shortages and high salinity affect many countries. With global warming, we can expect to see more droughts and so water will become an even scarcer resource. Hopefully this technology will help ensure we have sustainable water supplies for decades to come.

“It will enable policymakers to decide potential sites for recharging the groundwater aquifers without depleting or harming the environment,” he says.

Dr Ahmed’s study has been published in the journal Water, with contributions from colleagues in the Desert Research Centre, Egypt, and King Abdulaziz City for Science and Technology, Saudi Arabia.

 

Gardening for wildlife enhances bird diversity beyond your own back yard


Peer-Reviewed Publication

USDA FOREST SERVICE - NORTHERN RESEARCH STATION

Enhancing bird diversity with gardening. 

IMAGE: A USDA FOREST SERVICE SCIENTIST WAS PART OF A TEAM THAT EXPLORED THE VALUE OF THE BIGGEST CHUNK OF GREEN SPACE FOUND IN CITIES - RESIDENTIAL YARDS - AS WILDLIFE HABITAT. PHOTO SHOWS COREOPSIS, BEE BALM, AND PURPLE CONEFLOWER NEAR A RESIDENTIAL MAILBOX. view more 

CREDIT: PHOTO BY DAVID MIZEJEWSKI, NATIONAL WILDLIFE FEDERATION.

MADISON, WI, Oct. 25, 2021 — Households manage their yards in diverse ways and new research has found that their landscaping and management decisions have the potential to increase wild bird habitat and influence bird biodiversity in their yard and also at the neighborhood and city scale.

Across the United States, bird populations are declining due to decreases in availability of habitat.  Recently, a team of scientists explored the value of the biggest chunk of green space found in cities – residential yards –as wildlife habitat.  A new study, “Residential yard management and landscape cover affect urban bird community diversity across the continental USA,” was published this month in the journal Ecological Applications.  The research was co-led by USDA Forest Service Research Ecologist Susannah Lerman and Post-Doctoral Researcher Desirée L. Narango from City University of New York and University of Massachusetts.  Together with partners they conducted bird diversity observations in four residential yard types and in natural parks in six cities with distinctly different climate conditions: Baltimore, MD; Boston, MA; Los Angeles, CA; Miami, FL; Minneapolis-St. Paul, MN; and Phoenix, AZ.  The researchers found similar patterns in all six cities; although urban parks support more species of conservation concern (an official designation of species whose long-term persistence is in question) compared with yards, yards certified as wildlife habitat through the National Wildlife Federation’s certification program support a wider variety of bird species compared with more traditional yard landscaping (e.g., lawn-dominated yards.) This suggests that landscape management for wildlife can contribute to region-wide bird diversity. The study also considered public interest levels based on Google searches and bird sightings and found that yards supported more popular species compared with parks.

“This study shows that when people landscape with wildlife in mind, householders can contribute to conservation right in their own back yards,” said Lerman, who is with the Forest Service’s Northern Research Station. “And our yards often support some of our most beloved backyard birds.”

“Scientists are finding that we can’t study cities in isolation.  It will improve bird conservation efforts if we can understand which management practices are effective across regions and nationally, and which are effective at a more local level, “ said Narango.

In addition to Lerman and Narango, co-authors include Meghan L. Avolio, Johns Hopkins University; Anika R. Bratt, Duke University and Davidson College; Jesse M. Engebretson, University of Minnesota; Peter M. Groffman, City University of New York and Cary Institute; Sharon J. Hall, Arizona State University; James B. Heffernan, Duke University; Sarah E. Hobbie, University of Minnesota; Kelli L. Larson, Arizona State University; Dexter H. Locke, USDA Forest Service; Christopher Neill, Woodwell Climate Research Center; Kristen C. Nelson, University of Minnesota; Josep Padullés Cubino, University of Minnesota and Masaryk University; and Tara L. E. Trammell, University of Delaware.

 

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Warmer water, less nutrition


The nutritional value of giant kelp decreases as sea temperatures increase

Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - SANTA BARBARA

As a foundational species, giant kelp (Macrocystis pyrifera) is vital to the ecosystem of the temperate, shallow, nearshore waters where it grows. When the kelp flourishes, so do the communities that rely on the fast-growing species for food and shelter.

Giant kelp has proven resilient (so far) to some stressors brought on by climate change, including severe storms and ocean heatwaves — an encouraging development for those interested in the alga’s ability to maintain the legions of fish, invertebrates, mammals and birds that depend on it for their survival. But in a recent study published in the journal Oikos, UC Santa Barbara researchers reveal that giant kelp’s ability to take a temperature hit may come at the cost of its nutritional value.

“The nutritional quality, or the amount of nutrients in the kelp tissue seems to be changing,” said the study’s lead author Heili Lowman, a biogeochemist with the University of Nevada, Reno, who conducted this research as a Ph.D. student in the Department of Ecology, Evolution and Marine Biology at UC Santa Barbara. “We found that those changes were associated or correlated with changing seawater temperatures. From a big-picture standpoint, that’s pretty important because there are a lot of things that rely on kelp as the primary food source.”

“I guess you could call it one of the more hidden effects of ocean warming,” said study co-author and graduate student researcher Kyle Emery. “We haven’t necessarily lost kelp in places that have had these big temperature increases, but the kelp there has declined in terms of its nutritional content. So although it’s still there, it’s not able to provide the same function as when temperatures are lower.”

These findings of ocean warming’s hidden effects on kelp come from long-term data gathered at UCSB’s Santa Barbara Coastal Long-Term Ecological Research (SBC-LTER) site, which consists of several kelp forests located in the Santa Barbara Channel. Thanks to data collected over almost two decades, researchers have been able to track patterns of nutrient content, which fluctuate seasonally, and identify significant trends.

“The temperature of the seawater and nutrient availability are really closely coupled in the Santa Barbara Channel, and we’ve known that for some time,” Lowman said. Generally, the cooler temperatures bring nutrient-rich waters up from the deep, but during the warmer seasons, nutrients in the shallows and upper ocean — particularly nitrogen — become more scarce.

“Physiologically, kelp plants can’t store nitrogen for longer than a couple weeks, so whatever’s happening around them in the water they’re going to respond to very quickly because they need a constant supply of nitrogen to grow, and to continue to reproduce,” she said.

Knowing this pattern, the researchers then sought out how nutrient content might play out over a longer period of time, as ocean temperatures rose. They did so by looking at data from the primary productivity sampling that is conducted in the waters at the SBC LTER on a monthly basis.

“As part of that sampling, kelp blades are collected from these sites, brought back to the lab and then processed for carbon and nitrogen content,” Emery explained.

Over the 19-year period covered by the SBC LTER, according to the paper, nitrogen content of the giant kelp tissue declined by 18%, with a proportional increase in carbon content, according to the paper.

This apparent decline in nutritional content does not bode well for the consumers of kelp in and around the Santa Barbara Channel, which include sea urchins and abalone in the water, and intertidal beach hoppers and other invertebrates that consume the kelp wrack that washes up on the shore.

“As a result, urchins, for example, might go in search of a lot more kelp and that could cause a shift in certain places, potentially from a kelp forest to an urchin barren, if they’re just mowing down the reef looking for more food,” Lowman said. Animals that feed on kelp might also expend more energy trying to eat enough to fulfill their nutritional requirements.

While urchins have the ability to go searching for more food, Emery added, the consumers on the shore are stuck with what they get.

“If you have greater demand, but there’s not more kelp coming in, that poses a pretty challenging situation for them, whether it’s being underfed or through population declines,” he said.

In both cases, the effects could ripple out to the rest of the food web, the researchers said: Lower-nutrition kelp could mean smaller, fewer, perhaps less healthy beach hoppers, for instance, which would lead to less food for the shorebirds that eat them. In the water, less nutrition for urchins and abalone could mean less food for their consumers, including fish, lobster, sea otters and humans.

“Our results raise a lot of really interesting open-ended questions and suggest a lot of far-reaching effects,” Emery said.

Having explored the potential relationships of seawater temperature to nutritional content, the researchers are considering broadening the spatial scale of the study.

“The next step would be thinking about what all is playing into determining the nutritional content and then how might we then be able to predict it into the future,” Lowman said.



WHY ISN'T THIS FRONT PAGE NEWS

Affordable policy which could stop fossil fuels causing global warming - report


Stop fossil fuels causing global warming within a generation... The Carbon Takeback Obligation could do just that

Peer-Reviewed Publication

UNIVERSITY OF OXFORD

Imagine a single policy, imposed on one industry, which would, if enforced consistently, stop fossil fuels causing global warming within a generation. The Carbon Takeback Obligation could do just that. It requires fossil fuel extractors and importers to dispose safely and permanently of a rising fraction of the CO2 they generate, with that fraction rising to 100% by the year of net-zero. Critically, this would include carbon dioxide generated by the products they sell.

A ground-breaking study by the Universities of Oxford and Edinburgh, published Tuesday [embargoed to 11am US ET] in the international energy journal Joule, explores the economic implications of imposing a carbon takeback obligation on the global fossil fuel industry, and shows it provides an affordable and low-risk route to net zero emissions, particularly if complemented by conventional measures to reduce near-term fossil fuel demand.

Oxford researcher Stuart Jenkins, lead author of the study, explains, ‘Despite the perceived high cost of carbon dioxide capture and storage, we show that the cost to the world economy of a Carbon Takeback Obligation, even if entirely passed on to fossil fuel consumers, is no higher than the cost of mitigation in conventional scenarios meeting similar goals driven by a global carbon price.’

Professor Stuart Haszeldine of the University of Edinburgh, a report co-author, says, ‘Investment in carbon dioxide capture and geological storage has, to date, been dependent on state subsidies, and consistently far below what is required to meet Paris climate goals. Carbon Takeback provides the fossil fuel industry itself with the strongest possible incentive to make amends: survival.’

Oxford’s Professor Myles Allen, another co-author adds, ‘Carbon Takeback has consistently been dismissed by the climate policy establishment as much more expensive and risky than the alternative of driving down consumption by changing consumer behaviour or through a global carbon price. But these options are hardly risk-free. Getting to net zero means carbon prices rising to $1000 per tonne of CO2 by 2050: 100 times the hike that brought out the gilets jaunes.’

Margriet Kuijper, an independent expert in carbon capture and storage who reviewed the work, comments, ‘A Carbon Takeback policy as proposed in this paper will provide a safety net to make sure we achieve net zero emissions even if we don’t manage to reduce the use of fossil fuels quickly enough. It extends the responsibility of producers to take care of the waste generated by the use of their products. The polluter pays to clean up. And the costs are included in the product price. As it should be.’



Notes to Editors:

The paper: Upstream decarbonisation through a Carbon Takeback Obligation: an affordable backstop climate policy is the Climate & Energy highlight of this week’s issue of the journal Joule published Tuesday, October 26, embargoed to 11am US ET. It will be available on https://www.cell.com/joule/fulltext/S2542-4351(21)00489-X when the embargo lifts

True Planet: Oxford research for a changing world

The world around us is changing, and Oxford researchers are at the forefront of trying to understand better the reasons for global temperature and sea level increases, extreme weather events, plastic waste proliferation and threats to biodiversity.

Our researchers are working with partners in industry, government, the third sector and at other universities to address these challenges and to propose innovative approaches and solutions. Find out more about our True Planet campaign.

The University of Oxford

Oxford University has been placed number one in the Times Higher Education World University Rankings for the fifth year running, and at the heart of this success is our ground-breaking research and innovation. Oxford is world-famous for research excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research sparks imaginative and inventive insights and solutions.

 

UBC researchers are helping communities prepare for the effects of climate change


Business Announcement

UNIVERSITY OF BRITISH COLUMBIA

CHERP community information 

IMAGE: AN EXAMPLE SCREENSHOT OF THE CANADIAN HAZARDS EMERGENCY RESPONSE AND PREPAREDNESS MOBILE APP (CHERP) APP. view more 

CREDIT: CHERP RESEARCH TEAM

The 26th United Nations Climate Change Conference of the Parties (COP26) takes place next week and one of its four goals is to help countries adapt to climate change in order to protect communities and natural habitats.

From creating disaster preparedness apps to training local climate champions, UBC researchers are already working with communities to help them prepare for the effects of climate change.

App-daptation for disasters and hazards

Planning for a disaster can be scary, but UBC researchers are making it easier with a new app tailored to individual households.

Dr. Ryan Reynolds, a postdoctoral researcher in the faculty of applied science's school of community and regional planning, found residents in Port Alberni were confused as to which households were at risk and where to find information following a tsunami warning and evacuation in 2018.

Hoping to address this gap, his team has created the Canadian Hazards Emergency Response and Preparedness Mobile App (CHERP) app, which will be piloted in seven communities on Vancouver Island starting next month. “I know from speaking with people post-disaster that anything we can do to reduce that confusion goes a long way to building trust in emergency responses.”

The app helps residents create preparedness, communication, evacuation and on-the-day emergency response plans for local hazards and potential disasters such as sea level rise or coastal flooding. Not sure if your household is in the inundation zone for a tsunami warning? The app will tell you based on your location.

A thorough list of inputs helps individualize plans for each household, including whether someone menstruates, has anxiety, accessibility issues, is part of the LGBTQ+ community, signs, is a refugee or in Canada on a temporary visa. And pets aren’t forgotten: users can input the number of animals in their household.

Preparing for emergencies is like insurance, says Dr. Reynolds. “You do a little bit of work now and hopefully reap the benefits down the road. We know things like sea level rise, coastal flooding, tsunamis, are going to happen and we can put steps in place to prepare.”

CAPTION

An example screenshot of the Canadian Hazards Emergency Response and Preparedness Mobile App (CHERP) app.

CREDIT

CHERP research team

Wine, cheese and climate change

Tackling climate change over wine and cheese with your neighbours sounds too good to be true. But Dr. Stephen Sheppard, a professor emeritus in the department of forest resources management in the faculty of forestry, says local climate change action should be fun. “If you can get people to do things together, you get safer, more resilient neighbourhoods but also stronger communities. You could go to the pub, have some fun with it – it’s got to be fun, or no one will do it.” 

Over the next 12 months, his team will train local residents for Cool 'Hood Champs, a free program hosted by four Vancouver community centres. In a series of three workshops, participants learn to identify local climate targets, impacts and solutions, and craft their own climate action plans with practical actions, ranging from installing a shade for a vegetable garden to watering neighbourhood trees during a drought.

This year’s program is an extension of a pilot from last year, where 29 out of 37 participants completed all the workshops, and 70 per cent chose to take home trees to plant in their yards. Local action is vital, says Dr. Sheppard, because individual behavioural decisions affect whether governments achieve emissions targets, and practical solutions can help people feel better. “What can you do about climate change? You can ignore it, worry about it, or do something about it, using processes you can control.’

Dr. Sheppard and his team are also piloting a three-year program with Oak Bay council, where citizen workshops will be hosted through community hubs including schools, churches, and volunteer programs, with funding and staff support. “The pilot will show with backing and funding, citizens themselves can run workshops, take local action and involve others, sustainably.” 

CAPTION

An example screenshot of the Canadian Hazards Emergency Response and Preparedness Mobile App (CHERP) app.

CREDIT

CHERP research team

Adaptation, not maladaptation

However, climate adaptation interventions are not automatically positive, says Dr. Sameer Shah (he/him), a sessional lecturer at the UBC Institute for Resources, Environment and Sustainability (IRES) in the faculty of science. When applied without consideration of the social context, they can deepen inequities.

In a study published in June, Dr. Shah and colleagues looked into the Government of Maharashtra’s campaign in India to make 25,000 villages drought-free by 2019, a campaign that cost nearly US$1.3 billion.

The team interviewed households in three villages, as well as government officials and key informants, and found that government interests had led to a narrow focus on certain types of water conservation interventions. These benefited a particular group of people, generally those who were already well-off, and often excluded those who didn’t have enough land or money to invest in water-related adaptations, or were located further away from waterbodies, including members of historically disadvantaged groups.

According to a 2020 report by the Comptroller and Auditor General of India, the campaign had little impact in achieving water neutrality and increasing groundwater level.  Here, technical solutions are not enough, says Dr. Shah, and interventions need to incorporate the social context in which they occur. “As researchers, we can’t just say ‘this is the science’ for an intervention, and then hang up our hats. We need to be focused on issues of governance and distribution.”

Getting the global community involved

When it comes to climate action on mitigation and adaptation, we need everyone involved, says Dr. Jiaying Zhao, Canada Research Chair in Behavioral Sustainability and associate professor at IRES and the department of psychology in the faculty of arts.

She and her colleagues have posited a set of interventions to target different subsets of the entire population to make sure no one is left behind.

Two of these five groups, the “late majority” and the “laggards”, make up 50 per cent of the population and are often overlooked by behaviour change interventions, the authors say.

The “late majority" are characterized as adopting climate actions to fit in with others. Interventions include using social norms, peer pressure, and peer influence to encourage climate action. The “laggards”, or those most reluctant to act, need peer role models to deliver messages and to endorse climate action, says Dr. Zhao. “You need to use the right messenger to deliver the right message.”

Policy makers and researchers should acknowledge these different groups of people and their distinct motivations for climate action, and tailor interventions to each group, she says. “We should get everyone onboard, not just the keeners, as soon as possible.”

Citizen scientists’ contributions a boon to snowpack modeling, OSU research shows


Peer-Reviewed Publication

OREGON STATE UNIVERSITY

Snowpack research 

IMAGE: OSU CIVIL ENGINEERING PROFESSOR DAVID HILL CHECKS SNOWPACK DEPTH. view more 

CREDIT: KENDRA SHARP, OSU

CORVALLIS, Ore. – Data gathered by backcountry skiers, avalanche forecasters and other snow recreationists and professionals has the potential to greatly improve snowpack modeling, research by the Oregon State University College of Engineering indicates.

Findings, published in the journal Hydrology and Earth System Sciences, stem from a NASA-funded project known as Community Snow Observations, or CSO, part of NASA’s Citizen Science for Earth Systems program.

The paper is the first documentation of CSO’s power to make snowpack modeling better through “organic, opportunistic” data – a notable outcome, said researcher David Hill.

“We have shown citizen scientist contributions are very valuable and that we can do great things in the absence of observational network infrastructure,” said Hill, professor of civil engineering at OSU. “In this study, we used a new data set collected by CSO participants in coastal Alaska to improve snow depth and snow-water equivalent outputs from a snow process model.”

In western North America, snow’s role in ecosystem function and water resource management is critical, the scientists say, and around the world more than a billion people live in watersheds where snow is a major component of the hydrologic system.

“Snowpack dynamics in the mountains have a big role in connecting atmospheric processes and the hydrologic cycle with downstream water users,” said Chris Cosgrove, an OSU graduate student during the research. “At our Alaska field site, hydroelectric power generation is the principal concern, but in the lower 48, many agricultural producers and municipal water systems rely on seasonal snow.”

In 2017, NASA enlisted Hill and doctoral student Ryan Crumley, as well as researchers at the University of Washington, the University of Alaska Fairbanks and the Alaska Division of Geological & Geophysical Surveys, to recruit citizen scientists and incorporate their data into computer models that generate important snowpack information for scientists, engineers and land and watershed managers.

Community Snow Observations kicked off in February 2017 and since then thousands of data entries have been made. Led by Hill, Gabe Wolken of Alaska Fairbanks and Anthony Arendt of the University of Washington, the project first focused primarily on Alaskan snowpacks. Researchers then recruited citizen scientists in the Pacific Northwest and in the Rocky Mountain region.

The work is ongoing and getting involved in Community Snow Observations is easy. A smartphone, the free Mountain Hub application and an avalanche probe with graduated markings in centimeters are the only tools needed.

As citizen scientists make their way through the mountains, they use their avalanche probes to take snow depth readings that they then upload into Mountain Hub, an app for the outdoor community.

That’s all there is to it.

“We’ve now taken our modeling work operational,” Hill said. “We serve up real-time grids on snow information at many sites across the United States, including the central Cascades in Oregon, at mountainsnow.org. The general public can go there and view real-time information on snow, snow changes and other things like satellite measurements of snow.”

In the recently published research, Hill and Crumley, who’s now at the Los Alamos National Laboratory, teamed with Wolken, Arendt, Cosgrove and OSU graduate student Christina Aragon to look at how snowpack models for the Thompson Pass region of Alaska’s Chugach Mountains improved when citizen science measurements were incorporated.

“Improvements were seen in 62% to 78% of the simulations depending on the model year,” Aragon said. “Our results suggest that even modest measurement efforts by citizen scientists have the potential to improve efforts to model snowpack processes in high mountain environments.”

Information about snow distribution reaches scientists from many sources, including telemetry stations and remote sensing via light detection and ranging, or LIDAR, but the simplicity of the citizen science data gathering approach allows for many gaps to be filled, the scientists say.

“Snow depth measurements can be made accurately and quickly by anyone with a measuring device,” Crumley said. “The potential of mobilizing a new type of data set collected by people like snowshoers and snow machiners is significant because those folks often go to remote mountain environments where so far there haven’t been many observations recorded. All of those people can gather data at scales much greater than the capacity of a small group of scientists.”

Also collaborating on this research was Katreen Jones of the Alaska Division of Geological and Geophysical Surveys.

Project aims to improve accuracy of climate change models


Grant and Award Announcement

CORNELL UNIVERSITY

ITHACA, N.Y. - There’s broad scientific consensus that, because of climate change, the western U.S. will have less water and the northeastern U.S. will have more. But how much less and how much more is deeply uncertain, presenting a critical challenge for the scientists, policymakers and public servants tasked with ensuring the nation’s water supply.

Flavio Lehner, assistant professor of earth and atmospheric sciences at Cornell University, is working to reduce that uncertainty, by improving the climate models on which future water projections are based. Lehner won a three-year, $500,000 grant from the National Oceanic and Atmospheric Administration (NOAA) to do that work, beginning this fall.

Dan Barrie, a program manager in NOAA’s Climate Program Office, said Lehner’s work will improve NOAA’s climate models and enable the agency to make better short-term predictions of floods and droughts and better long-term projections of how surface water systems will evolve in the 21st century.

“The United States is experiencing profound changes in its regional water resources,” Barrie said. “It is more urgent than ever to have the best modeling tools to provide a vision of these future changes so that we can take cost-effective measures now to mitigate and adapt to them.”

Lehner’s research, which will improve climate modeling globally, was based on similar research he began in the Colorado River. Current estimates predict that for every degree Celsius of global warming, the Colorado River will lose between 3 to 15% of its streamflow.

Lehner compared the differences in climate models to the disparity in human reactions to COVID-19 – assessing whether an individual has COVID-19 is relatively simple, but predicting how sick the virus will make each person is much more difficult. A similar principle is at play in climate modeling, he said.

“For example, for the Colorado River, all of the numbers point in the same direction – in a warmer climate, there will be less water. But the big uncertainty is how much less,” Lehner said.

To test the sensitivity of climate models, Lehner’s group is studying 70 years of data on precipitation, temperature and streamflow, to assess how well current models would have predicted what actually happened.

“The most important question to us is: How sensitive are these models to changing environmental factors, such as changes in temperature and atmospheric greenhouse gases? And is their sensitivity consistent with what we see in reality?” he said.

The models Lehner and colleagues are using are more complicated and ultimately more useful because they take into account multiple interacting systems. Rather than just measuring rainwater or groundwater, Lehner is examining how atmospheric, terrestrial and hydrologic systems interplay, in the presence of increasing temperatures and atmospheric greenhouse gases. For example, there is now 40% more carbon dioxide in the air today than there was 100 years ago, and the earth is 1 degree Celsius warmer.  Even if precipitation remained neutral, those changes would cause plants to alter their behavior – consuming more groundwater to prevent parching, and thus leaving less to become stream runoff available to humans. But with added complexity comes added uncertainty.

“We already have a sizable uncertainty because we don’t know how much precipitation is going to change, but if you go one step further and say, how does runoff or streamflow change? The uncertainty becomes even larger,” Lehner said.

Modern climate modeling expanded dramatically in the 1980s and has provided useful and accurate information to help scientists and policymakers plan and adapt, Barrie said. Since 1980, the U.S. has experienced an average of 7.1 major weather or climate disasters per year, each causing losses of more than $1 billion. But in the past five years, the annual average of major disasters has jumped to 16.2, according to NOAA.

“Improving climate models is one step to ensuring that equitable adaptation efforts can be implemented to minimize net negative impacts on people and the economy. The cost of investments like Dr. Lehner's research project pales in comparison to the magnitude of the potential benefits,” Barrie said.

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Waters off French coast in winter may be a deadly trap for small, foraging turtles


The movement of turtles rescued from the French coast suggests they are visiting to forage for food, but small individuals may get trapped there in colder months


Peer-Reviewed Publication

FRONTIERS

The documented habitat boundaries of the loggerhead, Kemp’s ridley and green turtles are questioned by a new study suggesting that stranded turtles rescued from European French Atlantic and Channel waters could be visiting the area to forage for food. Published in Frontiers in Marine Science, satellite tracking data reveals that while some turtles may be able to return home, after their rehabilitation and release to Florida in the US, or Cape Verde off the African coast, younger individuals are at risk of being trapped in the region.

“Stranded turtles that were tracked swimming westwards presumably towards their birth homes, after their rescue and release from the Atlantic coast of France, were older and more developed than those that remained in the Bay of Biscay region,” said Dr Philippine Chambault, first author of this study, based at the Aquarium La Rochelle, France. “Turtles that remained in the area were much smaller, possibly trapped in the winter, as they are not able to regulate their body temperature and get lethargic with decreasing sea temperatures.”

“These findings have important turtle conservation implications,” added Florence Dell'Amico, co-author of the study, who oversees the Center of Studies, and cares for the sea turtles at the Aquarium La Rochelle. “Maps of their ecological range need to be updated, and these study findings can help to plan effective rehabilitation and release strategies for turtles rescued from this area.”

Rescue and rehabilitation

The Aquarium La Rochelle has rescued and rehabilitated more than 200 turtles from the east Atlantic coast of France in the past 40 years. To ensure the turtles they were caring for had the best chance of survival after their reintroduction back into the wild, the center wanted to understand where they travelled to after their release.

“Were the turtles returning to their natal beaches or staying within the Bay of Biscay region? To find out, we glued miniaturized satellite transmitters to the shells of some rescued turtles, which would track their movements over several months,” said Dell'Amico.

“In addition, we used the Copernicus Marine Service to obtain information on the currents, water temperatures and prey abundance along turtles’ trajectories. This enabled us to link turtle movement patterns to these oceanic factors, as well as the size and mass of the turtles,” explain Dr Philippe Gaspar, co-author of the study based at Mercator Ocean, France.

Too cold for small turtles?

“The Bay of Biscay waters are especially cold during wintertime, less than 10°C, and so this area is assumed to be outside the geographical range for turtles. Our observations suggest that while the turtles could be visiting this area to forage for food, it may be an ecological trap for very small turtles that may suffer from hypothermia in the cold months,” said Gaspar. “A turtle’s body temperature is largely controlled by the temperature of the environment, and temperatures below 10oC are often lethal.”

The team hope to satellite track more turtles in the region to confirm the surprising movement patterns they observed in this study.

“Future work should also focus on genetic analysis and computerized simulations of turtle movement across oceans to compare their routes back to their birth home to their natal origin. Simulations of juvenile turtle dispersal from the beaches that they were born should also be conducted to assess the proportion of individuals that reach western Europe,” concluded Chambault.