Thursday, March 11, 2021

Climate change influences river flow

ETH ZURICH

Climate change is affecting the water balance of our planet: depending on the region and the time of year, this can influence the amount of water in rivers potentially resulting in more flooding or drought. River flow is an important indicator of water resources available to humans and the environment. The amount of available water also depends on further factors, such as direct interventions in the water cycle or land use change: if, for example, water is diverted for irrigation or regulated via reservoirs, or forests are cleared and monocultures grown in their place, this can have an impact on river flow.

However, how river flow has changed worldwide in recent years was so far not investigated using direct observations. Similarly, the question whether globally visible changes are attributable to climate change or to water and land management had not been clarified.

Now, an international research team led by ETH Zurich has succeeded in breaking down the influence of these factors, after analysing data from 7,250 measuring stations worldwide. The study, which has been published in the renowned scientific journal Science, demonstrates that river flow changed systematically between 1971 and 2010. Complex patterns were revealed - some regions such as the Mediterranean and north-eastern Brazil had become drier, while elsewhere the volume of water had increased, such as in Scandinavia.

The quest for the causes

"The actual question, however, concerned the cause of this change," says Lukas Gudmundsson, lead author of the study and senior assistant in the group led by Sonia Seneviratne, professor at the Institute for Atmospheric and Climate Science at ETH Zurich.

To answer this question, the researchers carried out several computer simulations, using global hydrological models fed with observed climate data from the period studied (1971 to 2010). The results of the model calculations closely matched the analysis of observed river flow. "This means that climatic conditions can explain the observed trends in the flow volumes," says Gudmundsson. In a second procedure, the researchers included additional water and land management in their simulations in order to study the influence of these factors. This did not affect the result, however. "Changes in water and land management are evidently not the cause of global changes in rivers," he says.

Although water management and land use can result in large local fluctuations in flow volumes, investigating this was not within the scope of the study, adds Gudmundsson: "For us, it was not about local trends but global changes that become visible over longer periods." This is why the researchers did not consider data from individual measuring stations in isolation, but collated them into larger subcontinental regions for the analysis, thereby making it possible to identify the influence of climate change.

The impact of greenhouse gases

The researchers were able to substantiate the role of climate change using the detection and attribution method. For this they compared the observations with simulations from climate models that were calculated once with man-made greenhouse gases and once without. In the first case the simulation matched the actual data, but in the second case it did not. "This suggests that the observed changes are highly unlikely without climate change," says Gudmundsson.

The study is the first to use direct observations to demonstrate that climate change has a globally visible influence on rivers. "This was only possible thanks to the great collaboration between researchers and institutions from 12 countries," emphasises Gudmundsson. The data collection from the 7,250 measuring stations worldwide was also the result of a joint effort: researchers had collated the data with Australian collaboration partners in a previous study. This data now represents the largest global data set with river flow observations available today. "Thanks to this data, we were able to validate the models and demonstrate that they provide a good reflection of reality," says Gudmundsson.

This means that the models can also provide reliable scenarios on how rivers will continue to change in future. Such projections provide an important basis for planning in the affected regions in order to secure water supply and adjust to climate change.

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Has climate change altered river flows at a global scale?

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE

Research News

The pervasive fingerprint of anthropogenic climate change is apparent in river flow at a global scale, according to a new study. While anthropogenic climate change has had quantifiable and profound effects on various Earth systems, including the global water cycle, evidence for its role in the observed changes in river flow and hydrological extremes recorded worldwide remains uncertain. Lukas Gudmundsson and colleagues analyzed thousands of time series of low, mean and high river flows from 7,250 observatories worldwide from 1971 to 2010. According to Gudmundsson et al., the historical observations revealed recent, spatially complex global hydrological trends - while rivers in some regions are drying up and flowing less, others are growing wetter, with more water coursing between their banks. Using a climate change detection and attribution approach, the authors compared the observational data to Earth system model simulations of the terrestrial water cycle. According to the results, patterns in global river flow are only consistent with model predictions that consider the effects of radiative forcing from anthropogenic climate change. The simulated effects of water and land management alone are not enough to explain the recent patterns. The findings suggest that climate change is the causal driver influencing the magnitude of river flows globally. In a Perspective, Julia Hall and Rui Perdigão argue that, while Gudmundsson et al.'s attribution to climate change is logical and likely in terms of process understanding of climate dynamics, the evidence they provide is "circumstantial;" other processes not captured by the models could contribute to the observed trends. "To improve the explanatory power of such important studies and to generate more confidence in such attribution statements, we need to move beyond these first-order assessments that involve simple proof of consistency and inconsistency when investigating the effects of climate change," Hall and Perdigão write.

For reporters interested in trends, a February 2021 Science study reported that 53% of the world's river basins have undergone marked changes in biodiversity, largely due to human activity. https://science.sciencemag.org/cgi/doi/10.1126/science.abd3369

Paleontology: Microscope helps with dinosaur puzzle

Comparison of fossil bone tissue allows more reliable assignment to individuals

UNIVERSITY OF BONN

Research News

IMAGE: (HERE A TEAM FROM THE AATHAL DINOSAUR MUSEUM IN WYOMING, CO-AUTHOR HANS-JAKOB SIBER FRONT CENTER) OFTEN BELONG TO DIFFERENT ANIMALS. view more
CREDIT: (C) SAURIERMUSEUM AATHAL

Fossil sites sometimes resemble a living room table on which half a dozen different jigsaw puzzles have been dumped: It is often difficult to say which bone belongs to which animal. Together with colleagues from Switzerland, researchers from the University of Bonn have now presented a method that allows a more certain answer to this question. Their results are published in the journal Palaeontologia Electronica.

Fossilized dinosaur bones are relatively rare. But if any are found, it is often in large quantities. "Many sites contain the remains of dozens of animals," explains Prof. Dr. Martin Sander from the Institute of Geosciences at the University of Bonn.

If the finder is lucky, the bones are still arranged exactly as in the living dinosaur. Some are even still connected to each other at their joints. All too often, however, they were pulled apart and dispersed by scavengers and flowing water before being embedded in the soil. "Assigning this pile of hundreds of fossilized bones to the respective individuals from which they originally came is then usually very difficult," stresses Sander, who is also a member of the transdisciplinary research area "Building Blocks of Matter and Fundamental Interactions".

This is because, for one thing, "long bones" from the arms and legs, like the thigh bone, look remarkably similar even in different species. This means that even experts are often unable to say whether a fossil thigh bone is from Diplodocus or Brachiosaurus. And even if this could be ascertained, perhaps the excavation produced several Diplodocus specimens to which it could belong.

Sander and his doctoral student Kayleigh Wiersma-Weyand have now been able to demonstrate how this can be achieved. They used dinosaur bones from the U.S. state of Wyoming as a test object. These had been excavated and partially combined into skeletons by a team from the Aathal dinosaur museum in Switzerland shortly before the turn of the millennium.

CAPTION

the upper arm bone of a Diplodocus. The drill hole created during the removal of the fossil bone tissue sample is clearly visible.

CREDIT

Drilling into 150 million year old bones

The Swiss researchers made their finds available to the paleontologists in Bonn for the study. Wiersma-Weyand and Sander drilled into the 150-million-year-old bones and examined the extracted core under the microscope. "This allows us to find out how old the animal in question was when it died," Wiersma-Weyand explains. For one thing, young bones are better vascularized than old ones; this means that after fossilization they have more cavities in which the blood vessels used to be. Second, bone growth proceeds in spurts. "We therefore often see characteristic annual rings, similar to what we see in trees," the researcher says.

Estimating the age often makes it possible to rule out that a bone belongs to a particular skeleton. "If the left thigh bone is ten years older than the right one, we have a problem," Sander says laconically. There were no such discrepancies in the finds examined for the study. "However, we came across bones that had previously been attributed to two different animals, but probably belong to one and the same skeleton."

The study addresses a problem that has begun to come into scientific focus in recent years: With many mounted dinosaur skeletons located in museums and collections around the world, it is still not clear whether their bones come from one or more individuals. This combination is often done deliberately during mounting, since dinosaur skeletons are rarely preserved in their entirety. Supplementing missing bones with finds from other specimens is therefore common practice and, in principle, not a big deal as long as it is recorded. More critical, however, is when researchers combine finds unknowingly and these then come from different species or animals of different ages.

When the original Diplodocus has legs that are too short

This becomes particularly relevant when the skeletons are so-called type specimens. This is because these are considered the "standard" for the corresponding species, similar to the prototype meter. But what if, for example, the original Diplodocus contains the lower legs of a younger (and thus smaller) Diplodocus specimen? "Then some of the conclusions we draw about its locomotion and lifestyle may be wrong," Sander points out. "Our research therefore also helps combat the much-cited replication crisis in science."

Together with Kayleigh Wiersma-Weyand and Master student Nico Roccazzella, he will soon be using this method to take a closer look at a famous exhibit: the "Arapahoe" skeleton, the longest skeleton of a dinosaur in Europe, which is currently on display at the Museum Koenig in Bonn.

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Publication: Kayleigh Wiersma-Weyand, Aurore Canoville, Hans-Jakob Siber and Martin P. Sander: Testing hypothesis of skeletal unity using bone histology: The case of the sauropod remains from the Howe-Stephens and Howe Scott quarries (Morrison Formation, Wyoming, USA); Palaeontologia Electronica; DOI: https://doi.org/10.26879/766

CAPTION

and his colleague Kayleigh Wiersma-Weyand (below) plan to examine this dinosaur skeleton currently on display at the Museum Koenig, Bonn.

CREDIT

How does a crustacean become a crab?

Researchers find five independent carcinizations in both true and false crabs and at least seven instances of decarcinization

HARVARD UNIVERSITY, DEPARTMENT OF ORGANISMIC AND EVOLUTIONARY BIOLOGY

Research News

IMAGE: PHYLOGENETIC EVIDENCE FROM THE AUTHORS' PREVIOUS WORK DEMONSTRATES THAT CARCINIZED BODY PLANS HAVE EVOLVED MULTIPLE TIMES (INDICATED BY THE COLORED CHARACTERISTICS ON BRANCHES). CARCINIZED CLADES ARE: SPONGE CRABS, "HIGHER " TRUE... view more
CREDIT: COURTESY OF JOANNA M. WOLFE.

Crabs are living the meme life on social media lately. The memes joke that everything will eventually look like a crab. But it's actually based in some truth.

The crab shape has evolved so many times the evolutionary biologist L.A. Borradaile coined the term carcinization in 1916 to describe the convergent evolution process in which a crustacean evolves into a crab-like form from a non-crab-like form. Crabs are decapod crustaceans of the infraorder Brachyura and are considered "true crabs", most of which are carcinized. "False crabs" are of the infraorder Anomura. This group evolved crab-like body plans three or more times from an ancestor that was not carcinized.

In a paper published on March 12 in BioEssays, a team of researchers led by Harvard University found that the crab-like body plan evolved at least five times independently in both true crabs (Brachyura) and false crabs (Anomura). They also discovered the crab-like body plan has been lost at least seven times in a process called decarcinization.

The team, led by first author Joanna M. Wolfe, Postdoctoral Researcher, Department of Organismic and Evolutionary Biology (OEB), Harvard University, examined a composite of phylogenetic data for crabs. They synthesized morphological data from key fossil and living crab groups as well as data from behavior, natural history, functional morphology, and development all from previous studies by the authors.

Construction of comprehensive datasets, including fossil and extant species, representing all crab families is crucial to identifying the key characters that define what is a crab," said Wolfe. "This will allow us to resolve the multiple origins and losses of 'crab' body forms through time and identify the timing of origin of key evolutionary novelties and body plans."

Carcinization is characterized by a wide, flat carapace (the hard upper shell) and a folded pleon (the abdomen or tail). The pleon is largely hidden under the crab body, unlike the pleon of the lobster which is visible. In decarcinization the carapace is elongated and narrow. The pleon is not bent and is usually visible or even elongated. Decarcinization is an example of a group re-evolving a morphology that had been lost, which is thought to be a rare event in evolution.

"Biologists want to know how to "predict" if a phenotype, or morphology, would evolve in a group," said senior author Heather D. Bracken-Grissom, Associate Professor, Florida International University. "Examining crab evolution provides a macroevolutionary timescale of 250 million years ago for which, with enough phylogenetic and genomic data, we might be able to predict the morphology that would result."

Wolfe agreed, "Carcinization also allows us to compare convergent evolution in fossil morphology to that in living organisms, which is not yet commonly done."

The researchers are not completely certain but posit it is likely the common ancestor of Brachyura and Anomura was not carcinized. "This evidence suggests that indeed carcinization evolved independently in those groups," said co-author Javier Luque, Postdoctoral Researcher, OEB, Harvard University and Smithsonian Tropical Research Institute.

Wolfe is currently working with Assistant Professor Javier Ortega-Hernández, OEB, Harvard University, to test the hypothesis that carcinization can be quantitatively characterized by measuring the shapes of extant crab specimens from the Museum of Comparative Zoology, Harvard University, collections.

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This work was supported by the National Science Foundation DEB #1856679, DEB #1856667, and a National Sciences and Engineering Research Council of Canada (NSERC) Post- doctoral Fellowship.

Article and author details

Joanna M. Wolfe, Javier Luque, Heather D. Bracken-Grissom. 2021. How to become a crab: Phenotypic constraints on a recurring body plan. BioEssays DOI: 10.1002/bies.202100020

Corresponding author(s)

Joanna Wolfe, jowolfe@g.harvard.edu

#ENDWOLFHUNTING

Weakened protections led to more disappearances of endangered Mexican wolves

UNIVERSITY OF WISCONSIN-MADISON

Research News

MADISON, Wis. -- Mexican wolves in the American Southwest disappeared more quickly during periods of relaxed legal protections, almost certainly succumbing to poaching, according to new research published Wednesday.

Scientists from the University of Wisconsin-Madison found that Mexican wolves were 121% more likely to disappear -- despite high levels of monitoring through radio collars -- when legal rulings permitted easier lethal and non-lethal removal of the protected wolves between 1998 and 2016. The disappearances were not due to legal removal, the researchers say, but instead were likely caused by poachers hiding evidence of their activities.

The findings suggest that consistently strong protections for endangered predators lead to reduced poaching, contrary to theories that legalizing lethal removal might reduce the motivation to poach. Instead, the scientists say, strong protections could signal both the value of endangered predators and the government's intent to enforce protections. However, exactly how government policies ultimately influence poaching activity remains unclear.

"Top predators are very important to healthy ecosystems," says Adrian Treves, a UW-Madison professor of environmental studies who oversaw the new research. "They are imperiled globally by human activities. And among human-caused mortality, poaching is the leading cause."

Treves, graduate student Naomi Louchouarn and postdoctoral researcher Francisco Santiago-Ávila published their findings March 10 in the Royal Society Open Science journal. They collaborated with David Parsons, a former U.S. Fish and Wildlife Service agent and a member the Project Coyote science advisory board, to perform the analysis.

The new report comes on the heels of the federal government's delisting of the grey wolf in November 2020 under the Endangered Species Act, which reduced protections for the carnivores.

The Mexican wolf population, a subspecies of the grey wolf, is an ideal candidate for studying the effect of government policies. Thanks to intensive reintroduction efforts, more than half of the wolves are monitored through tracking collars, which provide high-quality data on the fate of individual wolves. Policies changed multiple times over roughly two decades, creating a natural experiment that researchers can use to observe how more relaxed or stringent protections affected wolf populations.

The Treves lab asked how two distinct changes in federal protections for Mexican wolves affected the mortality of the predators in the ensuing years. From 2005 to 2009, and again from 2015 until the end of the study period in 2016, federal regulators relaxed protections for the wolves. These new policies allowed agencies to more readily remove by lethal means wolves that were deemed threats to people or livestock. Public hunting was never legalized.

The researchers found that the only cause of lost wolves that changed significantly during times of reduced protections was a category known as lost-to-follow-up, or LTF. The LTF category includes all wolves that can no longer be accounted for. LTFs can be caused by radio collar battery failures, or by wolves migrating beyond the monitored area.

Yet, the U.S. Fish and Wildlife Service found few, if any, migrants out of the recovery area and LTF events occurred significantly earlier than the expected battery life of radio collars. Those results mean that these two common causes of LTF status likely can't account for the large increase in wolves lost-to-follow-up during years of relaxed protections. The Treves group also found no evidence of changes in diseases or climate that correlated with policy changes and would increase disappearances.

Instead, they believe that the increased risk of disappearance comes from poachers who act to hide their activities by destroying radio collars and hiding carcasses. Without that evidence, however, federal agencies can't confirm a cause of death, forcing them to declare the wolves lost-to-follow-up.

Agency removal of wolves and confirmed poaching activities did not vary significantly based on policy period.

"The fact that these changes line up with these periods really tells you a lot. The wolves don't understand that policy changed, but people do," says Louchouarn. "Yet the disappearances did increase, so somebody was changing their behavior. These methods really helped us to make that connection to likely poaching."

To reduce sources of bias, the researchers developed their methods and submitted them to peer review before completing their analysis. This pre-review encourages more transparent publishing of scientific findings, regardless of the final results.

"Our findings suggest that there is no evidence for the tolerance killing hypothesis, where allowing the killing of more individuals is going to increase the tolerance for the species and therefore reduce killings," says Santiago-Ávila, who originally developed the data analysis methods to study Wisconsin's wolf population. "There is a very minimal reduction in the poaching that gets reported. But that's only because the poaching gets translated to lost individuals, which we believe represents underreported poaching."

The researchers say government agencies should reassess their assumptions that lethal removal can ultimately lead to better outcomes for the wolves. Federal policies are developed based on scientific research, so reports like this one and a previous study of Wisconsin's wolf population could help federal agencies reevaluate for the future.

"Protection is the thing that's reducing poaching," says Treves.

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NICOLA TESLA'S DREAM

Contactless high performance power transmission

Superconducting coils for contactless power transmission in the kilowatt range

TECHNICAL UNIVERSITY OF MUNICH (TUM)

Research News

IMAGE: A TEAM OF PHYSICISTS AT THE TECHNICAL UNIVERSITY OF MUNICH HAS DEVELOPED A COIL MADE OF SUPERCONDUCTING WIRES THAT CAN TRANSMIT POWER OF MORE THAN FIVE KILOWATTS CONTACTLESS WITHOUT MAJOR... view more
CREDIT: CHRISTOPH UTSCHICK / WUERTH ELEKTRONIK EISOS

A team led by Christoph Utschick and Prof. Rudolf Gross, physicists at the Technical University of Munich (TUM), has developed a coil with superconducting wires capable of transmitting power in the range of more than five kilowatts contactless and with only small losses. The wide field of conceivable applications include autonomous industrial robots, medical equipment, vehicles and even aircraft.

Contactless power transmission has already established itself as a key technology when it comes to charging small devices such as mobile telephones and electric toothbrushes. Users would also like to see contactless charging made available for larger electric machines such as industrial robots, medical equipment and electric vehicles.

Such devices could be placed on a charging station whenever they are not in use. This would make it possible to effectively utilize even short idle times to recharge their batteries. However, the currently available transmission systems for high performance recharging in the kilowatt range and above are large and heavy, since they are based on copper coils.

Working in a research partnership with the companies Würth Elektronik eiSos and superconductor coating specialist Theva Dünnschichttechnik, a team of physicists led by Christoph Utschick and Rudolf Gross have succeeded in creating a coil with superconducting wires capable of contactless power transmission in the order of more than five kilowatts (kW) and without significant loss.

Reduced alternating current loss in superconductors

This meant the researchers had to overcome a challenge. Minor alternating current losses also occur in superconducting transmission coils. These losses grow as transmission performance increases, with a decisive impact: The surface temperature of the superconducting wires rises and the superconduction collapses.

The researchers developed a special coil design in which the individual windings of the coil are separated from one another by spacers. "This trick significantly reduces alternating current loss in the coil," says Christoph Utschick. "As a result, power transmission as high as the kilowatt range is possible."

Optimization with analytical and numerical simulations

The team chose a coil diameter for their prototype that resulted in a higher power density than is possible in commercially available systems. "The basic idea with superconducting coils is to achieve the lowest possible alternating current resistance within the smallest possible winding space and thus to compensate for the reduced geometric coupling," says Utschick.

This called on the researchers to resolve a fundamental conflict. If they made the distance between the windings of the superconducting coil small, the coil would be very compact, but there would be a danger of superconduction collapse during operation. Larger separations would on the other hand result in lower power density.

"We optimized the distance between the individual windings using analytical and numerical simulations," says Utschick. "The separation is approximately equal to half the width of the tape conductor." The researchers now want to work on further increasing the amount of transmittable power.

Exciting application areas

If they succeed, the door will open to a large number of very interesting application areas, for example uses in industrial robotics, autonomous transport vehicles and high-tech medical equipment. Utschick even envisions electric racing vehicles which can be charged dynamically while on the race track, as well as autonomous electric aircraft.

Wide-scale applicability of the system still faces an obstacle, however. The coils require constant cooling with liquid nitrogen, and the cooling vessels used cannot be made of metal. The walls of metal vessels would otherwise heat up considerably in the magnetic field, much as a pot does on an induction stove.

"There is as yet no cryostat like this which is commercially available. This will mean an extensive amount of further development effort," says Rudolf Gross, Professor for Technical Physics at the Technical University of Munich and Director of the Walther-Meissner-Institute of the Bavarian Academy of Sciences and Humanities. "But the achievements up to now represent major progress for contactless power transmission at high power levels."

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Cooperation partner Würth Elektronik eiSos defined the topic and financed the industrial promotion underlying this publication. Essential parts of the research were conducted at the Walther-Meissner-Institute (WMI) of the Bavarian Academy of Sciences and Humanities. The high-temperature superconductors used were provided by Theva Dünnschichttechnik, a spin-off company of the Technical University of Munich.

Publication:

Christoph Utschick, Cem Som, Ján Souc, Veit Große, Fedor Gömöry and Rudolf Gross
Superconducting Wireless Power Transfer Beyond 5 kW at High Power Density for Industrial Applications and Fast Battery Charging.
IEEE Transactions on Applied Superconductivity, 2. Februar 2021 - DOI: 10.1109/TASC.2021.3056195

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

Air pollution: The silent killer called PM2.5

Over half the world's population lives without the protection of proper air quality standards

MCGILL UNIVERSITY

Research News

Millions of people die prematurely every year from diseases and cancer caused by air pollution. The first line of defence against this carnage is ambient air quality standards. Yet, according to researchers from McGill University, over half of the world's population lives without the protection of adequate air quality standards.

Air pollution varies greatly in different parts of the world. But what about the primary weapons against it? To find answers, researchers from McGill University set out to investigate global air quality standards in a study published in the Bulletin of the World Health Organization.

The researchers focused on air pollution called PM2.5 - responsible for an estimated 4.2 million premature deaths every year globally. This includes over a million deaths in China, over half a million in India, almost 200,000 in Europe, and over 50,000 in the United States.

"In Canada, about 5,900 people die every year from air pollution, according to estimates from Health Canada. Air pollution kills almost as many Canadians every three years as COVID-19 killed to date," says co-author Parisa Ariya, a Professor in the Department of Chemistry at McGill University.

Small but deadly

Among the different types of air pollution, PM2.5 kills the most people worldwide. It consists of particles smaller than approximately 2.5 microns - so small that billions of them can fit inside a red blood cell.

"We adopted unprecedented measures to protect people from COVID-19, yet we don't do enough to avoid the millions of preventable deaths caused by air pollution every year," says Yevgen Nazarenko, a Research Associate at McGill University who conducted the study with Devendra Pal under the supervision of Professor Ariya.

The researchers found that where there is protection, standards are often much worse than what the World Health Organization considers safe. Many regions with the most air pollution don't even measure PM2.5 air pollution, like the Middle East. They also found that the weakest air quality standards are often violated, particularly in countries like China and India. In contrast, the strictest standards are often met, in places like Canada and Australia.

Surprisingly, the researchers discovered that high population density is not necessarily a barrier to fighting air pollution successfully. Several jurisdictions with densely populated areas were successful in setting and enforcing strict standards. These included Japan, Taiwan, Singapore, El Salvador, Trinidad and Tobago, and the Dominican Republic.

"Our findings show that more than half of the world urgently needs protection in the form of adequate PM2.5 ambient air quality standards. Putting these standards in place everywhere will save countless lives. And where standards are already in place, they should be harmonized globally," says Nazarenko.

"Even in developed countries, we must work harder to clean up our air to save hundreds of thousands of lives every year," he says.

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About this study

"Air quality standards for the concentration of particulate matter 2.5, global descriptive analysis" by Yevgen Nazarenko, Devendra Pal, and Parisa Ariya was published in the Bulletin of the World Health Organization.

DOI: http://dx.doi.org/10.2471/BLT.19.245704

About McGill University

Founded in Montreal, Quebec, in 1821, McGill University is Canada's top ranked medical doctoral university. McGill is consistently ranked as one of the top universities, both nationally and internationally. It?is a world-renowned?institution of higher learning with research activities spanning two campuses, 11 faculties, 13 professional schools, 300 programs of study and over 40,000 students, including more than 10,200 graduate students. McGill attracts students from over 150 countries around the world, its 12,800 international students making up 31% of the student body. Over half of McGill students claim a first language other than English, including approximately 19% of our students who say French is their mother tongue.

https://www.mcgill.ca/newsroom/

Paper: Personal charitable donation budgets flexible in aftermath of deadly storms

UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN, NEWS BUREAU

Research News

IMAGE: NEW RESEARCH CO-WRITTEN BY UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN EXPERTS TATYANA DERYUGINA AND BENJAMIN M. MARX FINDS THAT CHARITABLE GIVING IN THE AFTERMATH OF CATASTROPHIC TORNADOES DOESN'T NECESSARILY CROWD OUT DONATIONS... view more
CREDIT: PHOTO BY L. BRIAN STAUFFER

CHAMPAIGN, Ill. -- Charitable donations account for about 2% of gross domestic product in the U.S., but it's not well-understood whether an event such as a deadly storm inspires increases in charitable giving or simply reallocates a fixed supply of donation dollars that would have otherwise gone to another cause.

A new paper from a team of University of Illinois Urbana-Champaign experts finds that, in the aftermath of catastrophic tornadoes, charitable giving to alleviate an unanticipated event doesn't necessarily crowd out monetary donations to other causes.

Research co-written by Tatyana Deryugina and Benjamin M. Marx uses comprehensive annual tax return data to estimate whether discrete but destructive events such as fatal tornadoes increase total charitable giving.

The paper, which will be published in the journal American Economic Review: Insights, finds that each tornado fatality increases total donations from individuals living nearby by almost $2 million.

"There is an active debate in the research on charitable giving on the extent of donor substitution between charitable causes," said Deryugina, a professor of finance at Illinois. "By employing a natural experiment with both geographic and temporal variation as well as datasets that contain the majority of dollars donated across the U.S., our paper can rule out the possibility that individuals choose a set amount to donate to charity and then apportion that amount among charities."

The researchers measured charitable giving from 2002-17 using ZIP code-level individual income tax data from the Internal Revenue Service, which reports all income tax deductions claimed for donations to any registered charity.

By combining the IRS data with geospatial information on the incidence of tornadoes, the researchers were able to zero in on the destruction wrought by lethal tornadoes, allowing them to identify events that affected populated areas and caused tens of millions of dollars' worth of damage.

"We looked at tornadoes because they hit a very specific and limited area, which gives us a treatment area and a clean control area so we can get better estimates via comparison," said Marx, a professor of economics at Illinois.

Deryugina and Marx found that lethal tornadoes significantly increased total charitable donations from individuals living at least 20 miles away in the same state from a tornado's path by almost $2 million per fatality.

"We excluded ZIP codes that were within 20 miles of the tornado's path, so we weren't looking at the places that were directly affected by property damage or loss of life," Marx said. "We went outside of that 20-mile ring and out to the rest of the state to estimate the effect on average giving in those other ZIP codes. And if you add up those effects across all of those ZIP codes, you arrive at a total state-level effect, which is where the $2 million figure comes from."

Because total giving increases, the scholars were able to rule out perfect substitution between charitable causes and conclude that the supply of donations from an "altruism budget" can expand given exigent circumstances, Deryugina said.

"We can't rule out that there's some marginal crowding-out effects, because we just find that total giving goes up, but I'm comfortable speculating that there's not a lot of substitution because the total increase is fairly large," she said. "If there is some substitution, it's not huge. Basically, we see no evidence for the existence of a radical pullback in charitable giving to other causes after these natural disasters."

Using annual tax return data from charities, the researchers also found that there were no significant negative effects on charities in the locations from which increased donations to fatal tornadoes originated.

"That implies that giving in response to new needs doesn't come at the expense of these other causes," Marx said.

Charitable giving for natural disasters is common, with a nationally representative survey indicating that about 30% of U.S. households donated money in 2017-18. While the data in the paper covered the majority of dollars donated, it may not be representative of lower-income households, whose charitable donation budget may be more fixed, the researchers said.

"We only had aggregate, ZIP code-level data. We would have loved to break it down by income group, but we just didn't have the data," Deryugina said. "We do note in the paper that most charitable giving in the U.S. is by wealthier people. Lower-income individuals and households are less likely to file taxes, and all of our data came from the IRS. So our estimates are representative of individuals who filed a tax return, but those individuals make up a sizable share of total charitable giving."

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The research was supported by the Lilly Family School of Philanthropy.

Climate change may not expand drylands

New analysis highlights uncertainty about the future state of drylands

HARVARD JOHN A. PAULSON SCHOOL OF ENGINEERING AND APPLIED SCIENCES

Research News

Previous studies used atmospheric information, including rainfall and temperature, to make projections about future land conditions. The real picture is more complicated than that, said Kaighin McColl, Assistant Professor of Earth and Planetary Sciences and of Environmental Science and Engineering at SEAS and senior author of the paper.

"Historically, we have relatively good records of rainfall and temperature but really poor records of the land surface, things like soil moisture and vegetation," said McColl. "As a result, previous definitions of drylands are based only on how the atmosphere is behaving, as an approximation of the land surface. But models can now simulate both atmospheric and land conditions. By just looking directly at the land surface in climate models, we find that the models aren't showing a clear increase of drylands over time and that there is huge uncertainty about the global average state of drylands in the future."

The research is published in Nature Climate Change.

"If you want to know if the land is going to get drier, if crops are going to fail or if a forest is going to dry out, you have look at the land itself," said Alexis Berg, a research associate in McColl's lab and first author of the paper. "How much vegetation is there? Are the plants water stressed?"

While climate models have historically focused on the atmosphere, modern climate models now also simulate vegetation behavior and land hydrology.

For example, when plants absorb CO2, they lose water. If there is more CO2 in the air, plants can release less water and become more water efficient. More CO2 also results in more fertilizer for plants, which helps them grow and reduces water stress.

These effects have long been known, but previous atmospheric-only indicators of drylands just weren't capturing these land surface effects.

"As the climate is warming, there is a divergence between atmospheric and land surface behavior," said Berg.

To account for that divergence, McColl and Berg developed a new metric of drylands, based on land surface properties, including biological responses to higher atmospheric CO2, and compared drylands projections to those derived solely from atmospheric metrics.

"Our research shows that while some drylands may expand, climate models don't project that there will be a dramatic and rapid global expansion of drylands," said McColl.

However, simulating complex land processes remains challenging in global models.

"There is still a lot of uncertainty about how vegetation and the water cycle will change in a warming world," said McColl.

McColl and his team aim to reduce that uncertainty in future research by developing more accurate land surface models.

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This research was supported in part by a Winokur Seed Grant in Environmental Sciences from the Harvard University Center for the Environment.

Global battle against antibiotic resistance requires tailored solutions

RADBOUD UNIVERSITY MEDICAL CENTER

Research News

The global battle against antibiotic resistance can only succeed if local contexts are taken into account. "A tailored approach is needed in each country," says Heiman Wertheim of Radboud university medical center. "There is no "one-size-fits-all' solution." This was the main finding of a study on antibiotic resistance in African and Asian countries funded by the British Wellcome Trust. Wertheim is the lead investigator of a large group of international researchers who recently published an article on this study in The Lancet Global Health.

Antibiotics are powerful treatments for bacterial infections. They are indispensable for controlling infections such as pneumonia, meningitis, or blood poisoning (sepsis) caused by bacteria. But they are ineffective for treating viral infections, such as colds or flu, and do not work against infections with parasites, fungi or yeasts either.

Increasing resistance

Incorrect use of antibiotics increases the risk of antibiotic resistance. This means that bacteria adapt in such a way that the antibiotic is no longer effective and the disease can no longer be controlled. Antibiotic resistance is now a major problem worldwide.

The problem is growing especially in Low- and Middle-income Countries (LMIC), where antibiotic use increased by 35 percent between 2000 and 2010. Research in various countries show that for example 80 percent of children under the age of five with respiratory infections are treated with antibiotics. In many cases, this was unjustified. To gain more insight into this problem, a large group of international researchers led by Heiman Wertheim from Radboud university medical center carried out the ABACUS project. ABACUS stands for AntiBiotic ACces and USe.

Large differences between countries

The results of the study, which was conducted in LMIC countries in Africa (Mozambique, Ghana, South Africa) and Asia (Bangladesh, Vietnam, Thailand), have now been published in The Lancet Global Health. Wertheim: "We looked primarily at how easy or difficult it is to obtain antibiotics in those countries and in which situations they are used. On those aspects alone, we found enormous differences between the six countries. For example, in some countries you can purchase antibiotics in the pharmacy only with a doctor's prescription, while in others there are no restrictions and antibiotics are available at any time from the drug store around the corner. We also saw that antibiotics are much more readily available in Asia than in Africa. And that the situation is relatively better in wealthier countries such as Thailand and South Africa."

Self-medication

Nga Thi Thuy Do, a researcher at the Oxford University Clinical Research Unit in Vietnam and lead author of the paper, summarizes the findings as follows: "Bangladesh and Vietnam have the most places where antibiotics can be purchased without a prescription. In some settings you have one drugseller per 500 inhabitants, which is an awful lot. This is reflected in the extent to which antibiotics are used as self-medication. In Vietnam, Bangladesh and Ghana, 57 percent, 45 percent and 36 percent of the population, respectively, regularly take antibiotics for self-medication. But self-medication is much less frequent in Mozambique, Thailand and South Africa, with rates of 8 percent, 4 percent and 1 percent, respectively. The difference is enormous."

The researchers also observed quite some uncertainty in the local population - even among the sellers of antibiotics - about what an antibiotic actually is and how you can recognize it. For example, painkillers were sometimes confused with antibiotics. In a follow-up study, also funded by the Wellcome Trust, the consortium will investigate whether improved recognition of antibiotics can lead to better use.

Context, context, context

The reasons for opting for self-medication are obvious: getting antibiotics from the drugstore without a prescription is faster, cheaper and easier. But purchasing antibiotics without a prescription is not always possible. And that in turn depends on all kinds of factors such as how the healthcare is organized, whether consumers trust the supplier and the severity of the disease. Wertheim: "Our research makes it clear that a generic approach towards combating antibiotic resistance is ineffective. To have any chance of success, you must consider the context that affects the availability and use of antibiotics in each country. The conclusions of our study provide an excellent starting point for giving shape to global initiatives to improve antibiotic use, so that those who really need it can get the right antibiotic and those with a runny nose can get a 'warm cup of tea'."

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https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(21)00024-3/fulltext