Friday, November 06, 2020

Ancient crocodiles' family tree reveals unexpected twists and turns

Scientists probing a prehistoric crocodile group's shadowy past have discovered a timeless truth - pore over anyone's family tree long enough, and something surprising will emerge.

UNIVERSITY OF EDINBURGH

Research News

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IMAGE: ARTIST'S IMPRESSION OF MACROSPONDYLUS- AN EXTINCT FOSSIL GROUP OF TELEOSAURIODS. view more 

CREDIT: NIKOLAY ZVERKOV

Scientists probing a prehistoric crocodile group's shadowy past have discovered a timeless truth - pore over anyone's family tree long enough, and something surprising will emerge.

Despite 300 years of research, and a recent renaissance in the study of their biological make-up, the mysterious, marauding teleosauroids have remained enduringly elusive.

Scientific understanding of this distant cousin of present day long snouted gharials has been hampered by a poor grasp of their evolutionary journey - until now.

Researchers from the University of Edinburgh have identified one previously unknown species of teleosauroid and seven of its close relatives - part of a group that dominated Jurassic coastlines 190 to 120 million years ago.

Their analysis offers tantalising glimpses of how teleosauroids adapted to the momentous changes that occurred during the Jurassic period, as the earth's seas experienced many changes in temperature.

"Our study just scratches the surface of teleosauroid evolution," says study lead Dr Michela M. Johnson, of the University's School of GeoSciences. "But the findings are remarkable, raising interesting questions about their behaviour and adaptability.

"These creatures represented some of the most successful prehistoric crocodylomorphs during the Jurassic period and there is so much more to learn about them."

The study reveals that not all teleosauroids were engaged in cut and thrust lifestyles, snapping at other reptiles and fish from the seas and swamps near the coast.

Instead, they were a complex, diverse group that were able to exploit different habitats and seek out a variety of food sources. Their physical make-up is also more diverse than was previously understood, the scientists say.

Previous research had provided insights into the origins and evolution of this fossilised croc's whale-like relatives metriorhynchids, but less was known about teleosauroids.

To address this, the expert team of palaeontologists examined more than 500 fossils from more than 25 institutions around the world.

Cutting edge computer software enabled the team to glean swathes of revealing data regarding their anatomical similarities and differences, by examining the entire skeleton, teeth and bony armor, which indicated whether species were closely related or not.

This information enabled the team to create an up-to-date family tree of the teleosauroids group from which emerged two new large groups, whose anatomy, abundance, habitat, geography and feeding styles differ from one another significantly.

The first group, teleosaurids, were more flexible in terms of their habitat and feeding. The second group known as machimosaurids - which included the fearsome turtle crushers, Lemmysuchus and Machimosaurus - were more abundant and widespread.

Names given by the team to seven newly described fossils, found in both teleosaurids and machimosaurids, reflect a curious range of anatomical features - among them Proexochokefalos, meaning 'large head with big tuberosities' and Plagiophthalmosuchus, the 'side-eyed crocodile'.

There are even hints of their diverse behavioural characteristics and unique locations - Charitomenosuchus, meaning 'graceful crocodile' and Andrianavoay, the 'noble crocodile' from Madagascar.

Researchers have named the newly discovered species, Indosinosuchus kalasinensis, after the Kalasin Province in Thailand, where the fossil - now housed in Maha Sarakham University - was found.

The recognition of I. kalasinensis shows that at least two species were living in similar freshwater habitats during the Late Jurassic - an impressive feat as teleosauroids, with the exception of Machimosaurus, were becoming rare during this time.

Dr Steve Brusatte, Reader in Vertebrate Palaentology, at the School of Geosciences, University of Edinburgh, said: "The same way family trees of our own ancestors and cousins tell us about our history, this huge new family tree of teleosauroids clarifies their evolution. They were some of the most diverse and important animals in the Jurassic oceans, and would have been familiar sights along the coastlines for tens of millions of years."

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The study, published in the scientific journal PeerJ, was funded by the Natural Sciences and Engineering Council of Canada, SYNTHESYS Project and Leverhulme Trust Research. The Palaeontological Association and Paleontological Society provided travel grants.


#DMT

An Amazonian tea stimulates the formation of new neurons

UNIVERSIDAD COMPLUTENSE DE MADRID

Research News

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IMAGE: PREPARATION OF AYAHUASCA IN ECUADOR. / view more 

CREDIT: TERPSICHORE.

One of the main natural components of ayahuasca tea is dimethyltryptamine (DMT), which promotes neurogenesis --the formation of new neurons-- according to research led by the Complutense University of Madrid (UCM).

In addition to neurons, the infusion used for shamanic purposes also induces the formation of other neural cells such as astrocytes and oligodendrocytes.

"This capacity to modulate brain plasticity suggests that it has great therapeutic potential for a wide range of psychiatric and neurological disorders, including neurodegenerative diseases", explained José Ángel Morales, a researcher in the UCM and CIBERNED Department of Cellular Biology.

The study, published in Translational Psychiatry, a Nature Research journal, reports the results of four years of in vitro and in vivo experimentation on mice, demonstrating that these exhibit "a greater cognitive capacity when treated with this substance", according to José Antonio López, a researcher in the Faculty of Psychology at the UCM and co-author of the study.

Changing the receptor eliminates the hallucinogenic effect

Ayahuasca is produced by mixing two plants from the Amazon: the ayahuasca vine (Banisteriopsis caapi) and the chacruna shrub (Psychotria viridis).

The DMT in ayahuasca tea binds to a type-2A serotonergic brain receptor, which enhances its hallucinogenic effect. In this study, the receptor was changed to a sigma type receptor that does not have this effect, thus "greatly facilitating its future administration to patients".

In neurodegenerative diseases, it is the death of certain types of neuron that causes the symptoms of pathologies such as Alzheimer's and Parkinson's. Although humans have the capacity to generate new neuronal cells, this depends on several factors and is not always possible.

"The challenge is to activate our dormant capacity to form neurons and thus replace the neurons that die as a result of the disease. This study shows that DMT is capable of activating neural stem cells and forming new neurons", concluded Morales.

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References: Jose A. Morales-Garcia1, Javier Calleja-Conde, Jose A. Lopez-Moreno, Sandra Alonso-Gil1, Marina Sanz-SanCristobal, Jordi Riba y Ana Perez-Castillo. "N,N-dimethyltryptamine compound found in the hallucinogenic tea ayahuasca, regulates adult neurogenesis in vitro and in vivo" Translational Psychiatry (2020)10:331. DOI: 0.1038/s41398-020-01011-0.

 

On the hunt for wild bananas in Papua New Guinea


Scientists are racing to collect and conserve wild banana species; a recent expedition to the epicenter of banana diversity shows that wild species hold traits critical to helping the world's favorite fruit survive climate change, pests and diseases

INTERNATIONAL CENTER FOR TROPICAL AGRICULTURE (CIAT)

Research News

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IMAGE: SCIENTISTS BART PANIS AND A LOCAL GUIDE HOLD THEIR RARE FIND OF MUSA INGENS, A WILD SPECIES THAT GROWS UP TO 15 METERS IN HEIGHT. view more 

CREDIT: S.CARPENTIER

The banana has its earliest origins in Papua New Guinea, where it was domesticated by indigenous communities at least 7,000 years ago. This ancestor, Musa acuminata, subspecies Banksii, looks very different from the ubiquitous Cavendish banana: peeling back its skin reveals hundreds of large, hard seeds that enable easy reproduction in the wild.

Today, a colorful mix of wild bananas (including Banksii) still grow throughout the humid forests of New Guinea. However, as deforestation and fires decimate tropical and subtropical forests across the South Pacific, we risk losing both the ancestors and the possible future of the banana we know and love.

Against the backdrop of climate change, pests, and rampant diseases, researchers and crop breeders are scrutinizing diverse banana varieties for traits such as disease tolerance, pest resistance, and their ability to adapt to fluctuating temperatures. Wild bananas represent a largely untapped wealth of genetic diversity. Sebastien Carpentier, a scientist at the Alliance of Bioversity International and CIAT, explains: "It's very important for breeders to have access to crop wild relatives of bananas to help them find the traits that they are looking for."

Mission: search and collect

At the International Musa Germplasm Transit Center (ITC) in Leuven, Belgium, the Alliance manages the world's largest collection of banana germplasm. Yet despite currently holding 1,617 banana accessions, the genebank only scratches the surface of wild banana diversity. Bart Panis, a senior scientist based at the ITC, notes, "We don't know how much is out there."

In-situ conservation is becoming less likely with the loss of the wild bananas' habitat, therefore scientists like Panis are working against the odds to "fill in the gaps" by collecting samples in their native habitat, then transporting them to genebanks for further research and ex-situ conservation.

Last year, a collecting expedition touched down in Papua New Guinea that included Panis, Carpentier, and several other researchers collaborating with the county's National Agricultural Institute, NARI. For nearly two weeks, the team scoured terrain high and low, gathering a total of 31 bunches of eight different species while observing their adaptations in diverse environments.

One particularly fortuitous find was the giant Musa ingens. Despite competing with neighboring trees to grow as high as 15 meters, this towering species is no match for extensive land clearing and currently faces extinction.

Collection challenges

Collection is not easy work: elusive crop wild relatives are called wild for a reason. While they might have favorable traits, some species remain uncultivated because they are not edible for humans. Even banana specialists cannot always identify wild species in the field, and once they are found, the plants might not be in the brief stage where seeds or genetic material are available (bananas do not follow a predictable schedule for fruiting and flowering).

Preservation of viable material also makes successful storage and transportation a major challenge (fruits had to survive 2-4 weeks of travel before their seeds were extracted in Belgium). Furthermore, researchers must adhere to many countries' strict restrictions on the collection and transportation of plant genetic material.

Ensuring future generations of bananas

Back in Belgium, the team carefully stored genebank samples (techniques include drying and cryopreserving seeds) and began conducting a series of experiments to better understand the newly collected material.

Following field observation of Musa balbisiana persevering in open land recovering from fires (indicating the growth of extensive root systems to facilitate water uptake), the researchers have gained insights on water use efficiency, which could help breeders adapt bananas to resist future drought scenarios-- a serious priority as banana farmers currently suffer from up to 65% harvest losses related to drought.

Carpentier notes that there is also potential to fight pests and diseases, saying, "We need to continue to collect, store and screen for resistance in banana wild relatives." Other points of interest include health benefits (wild bananas have been used in traditional medicine, but this is not well-documented) and implications for increasing the yield of bananas per plant.

The results are summarized in two articles, one in Plants evaluating methods to ensure the viability of collected seeds, and the other in Crop Science summarizing the characterization of diverse phenotypes.

The scientists conclude that this work is just part of the ongoing effort to fill in knowledge gaps and ensure the survival of diverse, resilient bananas. Panis and Carpentier agree that it doesn't matter who does it, but it is critical that these banana wild relatives continue to be collected and conserved before they disappear forever.

CAPTION

A farmer carries a bunch of wild maclayi bananas in Papua New Guinea.

CAPTION

Bananas originally contained hard seeds. This trait can still be seen in wild species in Papua New Guinea.

 

Reduction of environmental pollutants for prevention of cardiovascular disease

It's time to act

DPT OF CARDIOLOGY - UNIVERSITY MEDICAL CENTER MAINZ

Research News

In a current opinion article "Reduction of environmental pollutants for prevention of cardiovascular disease: it's time to act", published in the European Heart Journal this week, a group of international environmental researchers from the University Medical Center of Mainz (Thomas Münzel and Andreas Daiber), from the University/BHF Centre for Cardiovascular Sciences, University of Edinburgh, United Kingdom (Mar Miller), the Diet, Genes and Environment, Danish Cancer Society Research Center, Copenhagen, Denmark (Mette Sørensen), the Max Planck Institute for Chemistry, Atmospheric Chemistry Department, Mainz, Germany (Jos Lelieveld) and the Harrington Heart and Vascular Institute, University Hospitals Cleveland Medical Center and School of Medicine, Cleveland, OH, USA (Sanjay Rajagopalan) summarized the epidemiologic and mechanistic evidence in support of an association between noise and air pollution with cardiovascular and metabolic disease, and recommended comprehensive mitigation measures.

Environmental risk factors are increasingly recognized as important determinants of cardiovascular disease (CVD). While the contribution of high cholesterol, diabetes, arterial hypertension, obesity and smoking are well established, the contribution by factors such as noise and air pollution to cardiovascular disease are often not acknowledged, despite the recognition that they represent the two most common and pervasive environmental risk factors globally.

Recent data indicate that air pollution attributable premature deaths approach 9 million per year globally (mostly cardiovascular causes), accounting for a loss of life expectancy that rivals that of tobacco smoking. The health burden due to noise pollution is mostly based on loss of healthy life years, amounting to several 100 Mio. of disability adjusted life years per year.

In particular with respect to air pollution, 90% of the world population lives in an environment with air pollution levels higher than 10μg/m3, being recommended by the WHO.

"The European levels air pollution limits for PM 25 μg/m3 is 2.5 fold higher than the WHO limit and a reduction of the air pollution limits down to the WHO recommendation mainly due to a phase out of fossil fuel use could prevent around 400.000 to 500.000 thousand excess deaths of Europeans. Thus, we urgently need to reduce these limits" urges Thomas Münzel.

The environmental stressors such as air pollution and noise pollution cause primarily cardiovascular disease such as chronic coronary artery disease, stroke diabetes mellitus, arterial hypertension but also neurological diseases and thus represent per se cardiovascular risk factors that can be positively influenced not by doctors or patients themselves but rather by politicians by introducing noise and air pollution limits that protect us from adverse health effects caused by these environmental stressors, "the lead author Münzel comments.

The author team proposes mitigation maneuvers for to protect from air pollution induced health side effects such as active personal exposure mitigation with home air cleaning and personal equipment such as N95 respirators while face masks are not effective in ?ltering PM2.5, Modification of human behavior to reduce passive exposures such as advising patients with pre-established cardiovascular disease to continue to remain >400 m away from major roadways to avoid exposure to traffic pollutants is a reasonable measure, despite the current lack of strong evidentiary support. Although a variety of over the counter drugs and medications have been shown to mitigate association between air pollution and surrogates, almost none can be recommended to protect against air pollution mediated adverse health effects at this time.

With respect to noise pollution the team suggests for road traffic noise that the sound generated by the contact between the tires and the pavement is the dominant noise source, at speeds above 35 km/h for cars and above 60 km/h for trucks. Therefore, changing to electric cars will result in only minor reductions in road traffic noise. Generally applied strategies for reducing road traffic noise include noise barriers in densely populated areas, applying quiet road surfaces, and reducing speed, especially during nighttime. Furthermore, there is a great potential in developing and using low-noise tires. As many of these mitigation methods result in only relatively small changes in noise a combination of different methods is important in highly exposed areas. For aircraft noise, mitigation strategies include to minimizing overlapping of air traffic routes and housing zones, introduction of night bans, and implementation of continuous descent arrivals, which require the aircraft to approach on steeper descents with lower, less variable throttle settings. For railway noise, replacing cast-iron block breaks with composite material, grinding of railway tracks and night bans, are among the preferred strategies for reducing noise. Lastly, installing sound-reducing windows and/or orientation of the bedroom towards the quiet side of the residence can reduce noise exposure.To this end Münzel further proposes that "increased awareness of the health burden posed by the risk factors such as noise and air pollution and their incorporation in traditional medical guidelines will help propel legislation to reduce them and significantly improve cardiovascular health."

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Link to the orginal paper: Reduction of environmental pollutants for prevention of cardiovascular disease: it's time to act European Heart Journal (2020) 00, 1-10 doi:10.1093/eurheartj/ehaa745

Policy, not tech, spurred Danish dominance in wind energy

CORNELL UNIVERSITY

Research News

ITHACA, N.Y. - In emerging renewable energy industries, are producers' decisions to shut down or upgrade aging equipment influenced more by technology improvements or government policies?

It's an important long-term question for policymakers seeking to increase renewable electricity production, cost-effectiveness and efficiency with limited budgets, says C.-Y. Cynthia Lin Lawell, associate professor in the Charles H. Dyson School of Applied Economics and Management at Cornell University.

In a new study focused on Denmark, a global leader in wind energy - a relatively mature and low-cost renewable technology - Lin Lawell found that government policies have been the primary driver of that industry's growth and development.

"Technological progress alone wouldn't have led to that widespread development of wind energy in Denmark," said Lin Lawell, the Robert Dyson Sesquicentennial Chair in Environmental, Energy and Resource Economics. "Well-designed policy may be an important contributor for nascent industries like renewables, which need to develop technology and which have broader societal benefits in terms of the environment."

Lin Lawell is the co-author with Jonathan Cook, an associate in her DEEP-GREEN-RADAR research group, of "Wind Turbine Shutdowns and Upgrades in Denmark: Timing Decisions and the Impact of Government Policy," published in a recent issue of The Energy Journal.

Wind turbines in many countries are approaching the end of their useful lives of roughly 20 years, Cook and Lin Lawell note, making decisions about whether to scrap or upgrade them increasingly relevant.

Denmark is ahead of that curve, having promoted wind energy since the oil crisis in the late 1970s. The country produces over 40% of its electricity from wind power and dominates other countries, the authors said, in wind deployment per capita and per gross domestic product. The Danish wind industry is highly decentralized, with 88% of the nearly 3,000 producers included in the 32-year study period from 1980-2011 operating no more than two turbines.

The researchers built a dynamic structural econometric model that incorporated the capacity, age and location of every turbine operated by small producers during that period. The model's "bottom-up" approach enabled analysis of individual owners' decisions to shut down, upgrade or add turbines over time, and simulated outcomes if government policies had been scaled back or were not implemented.

"Understanding the factors that influence individual decisions to invest in wind energy and how different policies can affect the timing of these decisions is important for policies both in countries that already have mature wind industries," the researchers wrote, "as well as in regions of the world that are earlier in the process of increasing renewable electricity generation (e.g. most of the U.S.)."

Denmark since the late 1970s has offered a feed-in tariff that guaranteed producers a fixed price per amount of wind energy generated, whether turbines were new or old. Since 1999, replacement certificates have incentivized upgrades.

Both policies significantly impacted small producers' shutdown and upgrade decisions and accelerated the development of Denmark's wind industry, the scholars concluded. Without them, the model showed most small-scale wind producers would have left the industry by 2011, concentrating production in larger wind farms.

However, the analysis determined that replacement certificates were far more cost-effective than the feed-in tariff in encouraging small producers to add or upgrade turbines, helping Denmark reduce its carbon emissions.

The study estimated the Danish government spent $3.5 billion on the feed-in tariff program over the study period, and as much as $114 million on the replacement certificates. Together, the two programs reduced carbon emissions by 57.4 million metric tons of carbon dioxide.

"One was just really expensive at doing it," Lin Lawell said. "Both the cost per metric ton of carbon dioxide avoided, and the cost per percentage point increase in payoff to the turbine owner, are much lower for the replacement certificate program."

For every million metric tons of carbon dioxide avoided, the researchers estimated the feed-in tariff cost Danish taxpayers $61.8 million, compared to $2.2 million or less for the replacement certificates.

Cook and Lin Lawell said their analysis offers lessons about the role of government policy in incentivizing the development of renewables and about which policies generate the most bang for the buck.

"Our application to the Danish wind industry," they wrote, "has important implications for the design of renewable energy policies worldwide."


 

Study shows disadvantaged communities may get overlooked for climate adaptation funding

Case study of California revealed an additional 348 communities eligible for funding

UNIVERSITY OF MIAMI ROSENSTIEL SCHOOL OF MARINE & ATMOSPHERIC SCIENCE

Research News

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IMAGE: EXTREME HEAT THREATENS THE WELLBEING OF PEOPLE ALL OVER THE WORLD, A NEW STUDY FROM SCIENTISTS AT THE UNIVERSITY OF MIAMI (UM) ROSENSTIEL SCHOOL OF MARINE AND ATMOSPHERIC SCIENCE FOUND... view more 

CREDIT: NASA

MIAMI--While extreme heat threatens the wellbeing of people all over the world, a new study from scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science found that some disadvantaged communities in California could be overlooked for state climate adaptation funds.

As government and communities across the U.S. ramp up efforts for equity-oriented climate change adaptation, questions about how to effectively identify and prioritize the limited funding across communities in practice remain.

In this study, researchers used California as a case study to evaluate how the state is targeting and prioritizing environmental justice communities for extreme heat adaptations. When the researchers analyzed CalEnviroScreen 3.0, California's program used to designate a census tract as "disadvantaged" and therefore eligible for equity-oriented project monies from the Greenhouse Gas Reduction Fund, they found that relying on CalEnviroScreen alone may result in the state overlooking 348 communities that would be eligible under two alternative indices.

"There are limits to the effectiveness of using a single index to guide a fund with projects and communities as diverse as those under the California Climate Investments program," said Lynée Turek-Hankins, a doctoral student at UM's Abess Center for Ecosystem Science and Policy and lead author of the study. "We highlight the need for context-specific tools that can capture local nuances and variabilities."

Although this study focused specifically on extreme heat in California, its findings are applicable for other climate-related hazards and states, said Turek-Hankins.

"Climate change is a threat multiplier for both people and nature. It amplifies risks for communities already grappling with environmental hazards and social stressors. But getting adaptation right at the implementation stage, attuned to differential impacts and benefits across communities, is far from straightforward," said Katharine Mach, associate professor in the Department of Marine Ecosystems and Society at the Rosenstiel School and a co-author of the study. "This analysis points to the importance of combining cross-cutting risk screening with attention to context--the hazards, the needs of communities, and the effectiveness of different resiliency strategies."

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The study, titled "Risk screening methods for extreme heat: implications for equity-oriented adaptation," was published on November 4, 2020 in the journal PLOS ONE, The study's authors include: Lynée Turek-Hankins, Katharine Mach from the University of Miami Rosenstiel School of Marine and Atmospheric Science; and Miyuki Hino from University of North Carolina at Chapel Hill.

The research was funded by the Mentoring Undergraduates in Interdisciplinary Research (MUIR) Program at the Stanford Woods Institute for the Environment, the Rosenstiel School of Marine and Atmospheric Science at the University of Miami, and the Abess Center for Ecosystem Science and Policy at the University of Miami.

About the University of Miami's Rosenstiel School

The University of Miami is one of the largest private research institutions in the southeastern United States. The University's mission is to provide quality education, attract and retain outstanding students, support the faculty and their research, and build an endowment for University initiatives. Founded in the 1940's, the Rosenstiel School of Marine & Atmospheric Science has grown into one of the world's premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life. For more information, visit: http://www.rsmas.miami.edu and Twitter @UMiamiRSMAS

 CLIMATE CHANGE 

Study projects more rainfall in Florida during flooding season

Researchers link Florida summertime rainfall with a warming Atlantic Ocean

UNIVERSITY OF MIAMI ROSENSTIEL SCHOOL OF MARINE & ATMOSPHERIC SCIENCE

Research News

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IMAGE: (A) MAP OF THE CORRELATION BETWEEN ATLANTIC SSTS AND PRECIPITATION FOR JUNE - OCTOBER IN GPCP (SQUARES) AND RAIN GAUGES (CIRCLES). (B AND C) CORRELATION BETWEEN ATLANTIC SSTS AND PRECIPITATION... view more 

CREDIT: JEREMY KLAVANS

MIAMI--A new study by researchers at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science projects an increase in Florida's late summertime rainfall with rising Atlantic Ocean temperatures.

Scientists have known for years that Florida receives more rainfall in decades when North Atlantic waters are warmer than average, but the UM research team wanted to learn more about this interaction to help communities prepare for a wetter future. This study showed that ocean temperatures are most influential on Florida precipitation in late summer, during the region's highest high tide events.

The researchers used a suite of climate models to show that the link between ocean temperatures and rainfall only develops as a result of human influences on the climate system, such as greenhouse gas emissions and industrial pollution.

"We know that humans are continuing to make North Atlantic waters warmer, so we expect an increase in late summer rainfall in Florida in the future," said Jeremy Klavans, a PhD student at the UM Rosenstiel School and lead author of the study.

The study, titled "Identifying the Externally?forced Atlantic Multidecadal Variability Signal through Florida Rainfall" was published in the early online edition of the American Geophysical Union's journal Geophysical Research Letters. The study's coauthors include: Jeremy Klavans, Amy Clement and Lisa Murphy from the UM Rosenstiel School; and Honghai Zhang, a UM Rosenstiel School alumni currently at Columbia University's Lamont?Doherty Earth Observatory.

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The study was funded by two National Science Foundation (NSF) grants-one from the NSF Climate and Large-Scale Dynamic program and one from the NSF Paleo Perspectives on Climate Change program.

About the University of Miami's Rosenstiel School

The University of Miami is one of the largest private research institutions in the southeastern United States. The University's mission is to provide quality education, attract and retain outstanding students, support the faculty and their research, and build an endowment for University initiatives. Founded in the 1940's, the Rosenstiel School of Marine & Atmospheric Science has grown into one of the world's premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life. For more information, visit: http://www.rsmas.miami.edu and Twitter @UMiamiRSMAS

UM research essential to global arctic animal migration archive

THE UNIVERSITY OF MONTANA

Research News

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IMAGE: A CARIBOU CALF FROLICS IN THE ARCHIVE STUDY AREA. view more 

CREDIT: PHOTO CREDIT TO KARSTEN HEUER

MISSOULA - Warmer winters, earlier springs, shrinking ice and increased human development - the Arctic is undergoing dramatic changes impacting native animals. And now, scientists can track the movements of thousands of Arctic and sub-Arctic animals over three decades with the new global Arctic Animal Movement Archive.

Researchers from around the world, including the University of Montana, have long observed the movements and behavior of animals in the Arctic, but have had difficulty discovering and accessing data. To solve the problem, an international team led by Sarah Davidson, data curator at the Max Planck Institute of Animal Behavior in Radolfzell, Germany, and Gil Bohrer, professor at Ohio State University, established the global data archive for studies of animal migration in the Arctic and sub-Arctic. It currently contains over 200 projects and movement data of more than 8,000 marine and terrestrial animals from 1991 to the present.

The archive, hosted on the Max Planck Institute's Movebank platform and funded by NASA, helps scientists share their knowledge and collaborate on questions on how animals are responding to a changing Arctic - particularly important because the Arctic region extends around the world. Researchers from more 100 universities, government agencies and conservation groups across 17 countries are involved in the archive.

UM contributors include Professor Mark Hebblewhite, graduate student Stephen Lewis and former postdoctoral researcher Eliezer Gurarie. Their research is part of Hebblewhite's funded NASA Arctic Boreal Vulnerability Experiment project that studies the effects of rapid climate change on wildlife in the Arctic, with a focus on caribou.

"UM has a long history, pioneered by researcher Steve Running, of understanding consequences of climate change to ecosystems, and this work builds on this important legacy in a region of the world undergoing some of the fastest rates of climate change, fires and impacts on people and nature," said Hebblewhite, who studies ungulate habitat ecology.

Three recent studies from the archive reveal large-scale patterns in the behaviors of golden eagles, bears, caribou, moose and wolves in the region and illustrate how the archive can be used to recognize larger ecosystem changes. The results were published Nov. 6 in an article in Science, one of world's premier scientific journals.

First, by comparing movements of more than 100 golden eagles from 1993 to 2017, researchers found that immature birds migrating north in the spring arrived earlier following mild winters. However, the arrival time of adults has remained rather constant, regardless of conditions at their breeding grounds, with consequences for nesting and chick survival.

The archive uses data from UM doctoral student Lewis, who is a wildlife biologist with the U.S. Fish and Wildlife Service Alaska Region, Division of Migratory Bird management. Lewis began studying the movements of golden eagles in 2012 to understand the costs of migration and carry-over effects of wintering in the contiguous U.S. for eagles born in Alaska. His data fit perfectly into the Arctic Animal Migration Archive and NASA's Arctic Boreal Vulnerability Experiment project, and he will continue to analyze eagle movement ecology at UM.

A second study of more than 900 female caribou from 2000 to 2017 found that more northern herds are giving birth earlier in the spring, while the calving dates of more southern populations have not shown the same change.

"Caribou are the Arctic's dominant large herbivore - an iconic symbol and crucial to Indigenous peoples for their food security and culture," Hebblewhite said. "Yet they are declining across the Arctic, and an obvious question is the role of climate change."

Hebblewhite said the research, which brought together an unparalleled dataset of nearly 1,000 GPS radio-collared caribou, showed a strong shift in calving dates across most of the region - and a potential contribution toward declining trends in the population.

A third analysis looking at the movement speeds of bears, caribou, moose and wolves from 1998 to 2019 showed that species respond differently to seasonal temperatures and winter snow conditions.

"Movement is central to animal survival in the harsh Arctic environment. Yet movement is costly, especially in the stark Arctic landscapes," Hebblewhite said. "Our work showed that increasing temperatures, especially in summer, were affecting movement rates of these large mammals, which could have energetic costs that stress these species. And changes in snow in the winter were also influencing wildlife movements - also in ways that could have population impacts."

In addition to the UM research and hundreds of studies already included in the archive, the resource is continually growing, as data are transmitted from animals in the field and more researchers join. Results should help detect changes in the behavior of animals and ultimately in the entire Arctic ecosystem.

"The Arctic is undergoing some of the most rapid climate change on the planet - upward of double the rates we are seeing here in Montana," Hebblewhite said. "We hope our collective work shows that the changes underway in the Arctic are real and strong and affecting almost all Arctic wildlife species, as well as the ecosystems and people who depend on them."

CAPTION

Two young golden eagles - one with a transmitter - nest on the Seward Peninsula, Alaska.

The Arctic Animal Movement Archive is online at https://www.movebank.org/cms/movebank-content/arctic-animal-movement-archive. The study, "Ecological insights from three decades of animal movement tracking across a changing Arctic," is online at https://science.sciencemag.org/content/370/6517/712.

Note: Movement is critical for animal life in the harsh Arctic. This GIF of Arctic Animal Movement Archive data shows the key role of the Arctic globally. https://umt.box.com/s/zf926rmtc8b68b9bokre6561sm8oaf6u.

 

Rivers melt Arctic ice, warming air and ocean

UNIVERSITY OF ALASKA FAIRBANKS

Research News

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IMAGE: WATER FROM CANADA'S MACKENZIE RIVER ENTERS THE BLUE ARCTIC OCEAN IN JULY 2012. WHITE AREAS IN THE TOP HALF OF THE PHOTO ARE LARGELY SEA ICE, WHILE THOSE BELOW ARE... view more 

CREDIT: PHOTO BY NASA EARTH OBSERVATORY

A new study shows that increased heat from Arctic rivers is melting sea ice in the Arctic Ocean and warming the atmosphere.

The study published this week in Science Advances was led by the Japan Agency for Marine-Earth Science and Technology, with contributing authors in the United States, United Arab Emirates, Finland and Canada.

According to the research, major Arctic rivers contribute significantly more heat to the Arctic Ocean than they did in 1980. River heat is responsible for up to 10% of the total sea ice loss that occurred from 1980 to 2015 over the shelf region of the Arctic Ocean. That melt is equivalent to about 120,000 square miles of 1-meter thick ice.

"If Alaska were covered by 1-meter thick ice, 20% of Alaska would be gone," explained Igor Polyakov, co-author and oceanographer at the University of Alaska Fairbanks' International Arctic Research Center and Finnish Meteorological Institute.

Rivers have the greatest impact during spring breakup. The warming water dumps into the ice-covered Arctic Ocean and spreads below the ice, decaying it. Once the sea ice melts, the warm water begins heating the atmosphere.

The research found that much more river heat energy enters the atmosphere than melts ice or heats the ocean. Since air is mobile, this means river heat can affect areas of the Arctic far from river deltas.

The impacts were most pronounced in the Siberian Arctic, where several large rivers flow onto the relatively shallow shelf region extending nearly 1,000 miles offshore. Canada's Mackenzie River is the only river large enough to contribute substantially to sea ice melt near Alaska, but the state's smaller rivers are also a source of heat.

Polyakov expects that rising global air temperatures will continue to warm Arctic rivers in the future. As rivers heat up, more heat will flow into the Arctic Ocean, melting more sea ice and accelerating Arctic warming.

Rivers are just one of many heat sources now warming the Arctic Ocean. The entire Arctic system is in an extremely anomalous state as global air temperatures rise and warm Atlantic and Pacific water enters the region, decaying sea ice even in the middle of winter. All these components work together, causing positive feedback loops that speed up warming in the Arctic.

"It's very alarming because all these changes are accelerating," said Polyakov. "The rapid changes are just incredible in the last decade or so."

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Authors of the paper include Hotaek Park, Eiji Watanabe, Youngwook Kim, Igor Polyakov, Kazuhiro Oshima, Xiangdong Zhang, John S. Kimball and Daqing Yang.

CAPTION

This diagram shows the relative amount of warming caused by Arctic rivers, with the sources of heat in orange and the heat sinks in turquoise. In spring, rivers flow into the Arctic Ocean, warming the water and melting sea ice, which in turn warms the atmosphere. A feedback occurs as the reflective ice disappears, allowing the dark ocean water to absorb more heat and melt more sea ice.