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Tag: Climate Science

  • Going for an immediate transition to a green economy pays off, even if such transition is very unlikely to happen, a study finds

    Going for an immediate transition to a green economy pays off, even if such transition is very unlikely to happen, a study finds

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    Newswise — Nicola Botta of PIK Potsdam, Germany, and colleagues have developed a new method for assessing how much decisions matter in situations in which the consequences of such decisions are highly uncertain. Applying the method to a stylized greenhouse-gas emission problem reveals that opting for an early transition to a decarbonized society is rational even when the probability of actually realizing such a transition is very low. The work “Responsibility under uncertainty: which climate decisions matter most?”, published in Environmental Modeling & Assessment is part of the European TiPES project on tipping points in the Earth’s system.

    ”We have discovered that it is almost always the case that best decisions are still best, even when the probability that they are actually implemented becomes very, very small,” says Nicola Botta.

    In the study, the group applied a verified theory of policy advice which makes it possible to compute “best” policies for problems in which decisions have to be taken step-by-step and under uncertainty.

    These policies are then compared, at a given decision step, with the remaining options to evaluate how important it is to avoid a mistake when taking a decision at that step.

    The method was then applied to a stylized greenhouse-gas emission problem in which the goal of decision making is twofold: 1) avoid unmanageable impacts from climate change and 2) avoid hurting the economy. The program now evaluated the consequences of two options: immediately start a transition to a green economy or postpone such a transition to avoid economical damage.

    The analysis indicates that best decisions pay off even when the probability that such decisions are actually implemented becomes very low, for example, because of political uncertainty or because of the inertia of legislation.

    ”At the first glance this seems surprising, as the common wisdom is that it’s not worth betting on something that is not likely to happen”, says Nicola Botta.

    ”But, if you think twice, the result makes sense. It also provides a guideline to the discussion on whether it is worth to pursue climatetargets (like the 1.5°C target) that are unlikely to actually be met: the answer is yes.”

    ”More generally, the paper is a methodological contribution towards understanding which decisions under uncertainty matter most. Realizing that certain decisions are less important than others (or less important than expected) can be very helpful, for example in climate negotiations” explains Nicola Botta.

     

    The TiPES project is an EU Horizon 2020 interdisciplinary climate science project on tipping points in the Earth system. 18 partner institutions work together in more than 10 countries. TiPES is coordinated and led by The Niels Bohr Institute at the University of Copenhagen, Denmark and the Potsdam Institute for Climate Impact Research, Germany. The TiPES project has received funding from the European Horizon 2020 research and innovation program, grant agreement number 820970.

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    University of Copenhagen, Faculty of Science

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  • Study reveals salps play outsize role in damping global warming

    Study reveals salps play outsize role in damping global warming

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    Newswise — Humans continue to amplify global warming by emitting billions of tons of carbon dioxide into the atmosphere each year. A new study reveals that a distant human relative plays an outsize role in damping the impacts of this greenhouse gas by pumping large amounts of carbon from the ocean surface to the deep sea, where it contributes nothing to current warming.

    The study, led by Dr. Deborah Steinberg of William & Mary’s Virginia Institute of Marine Science, appeared in the latest issue of Global Biogeochemical Cycles. It reports on research conducted as part of EXPORTS, a 4-year, multi-institutional field program funded by NASA. Co-authors hail from marine institutes in Maine, Bermuda, California, Newfoundland, British Columbia, and Alaska.

    The goal of EXPORTS, for EXport Processes in the Ocean from RemoTe Sensing, is to combine shipboard and satellite observations to more accurately quantify the global impact of the “biological pump.” This is a suite of biological processes that transport carbon and other organic matter from sunlit surface waters to the deep sea, effectively removing carbon dioxide from the surface ocean and atmosphere. Tiny drifting animals called zooplankton play a key role in the pump by eating phytoplankton, which incorporate carbon from carbon dioxide into their tissues during photosynthesis, then exporting that carbon to depth.

    During a month-long EXPORTS expedition to the northeast Pacific Ocean in 2018, Steinberg and colleagues chanced upon a large bloom of a poorly studied player in the biological pump: a species of gelatinous zooplankton named Salpa aspera. Like other salps, these “jelly barrels” begin life with a notochord—the structure that develops into the spinal cord in humans and other vertebrates—and as adults drift through the world’s oceans like tiny transparent whales, filtering microscopic plants afloat in the water. 

    Three features keyed the team’s interest in salps, and S. aspera in particular. One is that these organisms can reproduce asexually, rapidly cloning into immense blooms under the right conditions. Second is that S. aspera is bigger and filters more water than most other zooplankton, thus producing larger, heavier fecal pellets. Third is that it migrates up and down through the water each day, rising to feed on phytoplankton during the cover of night and jetting to the perpetual darkness of the deep sea during sunlit hours to avoid its own predators, which include sea turtles, marine birds, and fishes.

    Together, these features had led researchers to suspect that salps might play an important role in the biological pump, as large blooms of these relatively bulky zooplankton could effectively transport carbon to depth through their heavy, fast-sinking fecal pellets; vertical migrations that give those pellets a head start on their journey to depth; and the sinking of countless salp carcasses during a bloom (individual salps live only a few weeks).

    But the proof is in the pudding, and the ephemeral life cycle and uneven distribution of salps has long challenged efforts to study their role in carbon export and deep-sea food webs. “Salps follow a ‘bloom or bust’ life cycle,” says Steinberg, “with populations that are inherently patchy in space and time. That makes it hard to observe or model their contribution to the export of carbon to the deep sea.”

    During the 2018 EXPORTS expedition to the Pacific, Steinberg and colleagues were able to overcome these challenges by deploying a wide range of ocean-observation tools, from traditional plankton nets and sediment traps to underwater video recorders and sonar-based computer models. Moreover, by using two research vessels—the 277-ft Roger Revelleand the 238-ft Sally Ride—the scientists were able to observe conditions not only inside the salp bloom but in surrounding waters, providing a broader geographic context for their study.

    The results of the team’s unprecedented field campaign were clear. “High salp abundances, combined with unique features of their ecology and physiology, lead to an outsized role in the biological pump,” says Steinberg. 

    To put things in perspective, the observed salp bloom covered more than 4,000 square miles (~11,000 km2), about the size of Connecticut. With onboard experiments showing salps capable of exporting a daily average of 9 milligrams of carbon through each square meter at 100 meters below the bloom, the amount of carbon exported to the deep sea was about 100 metric tons per day. For comparison, a typical passenger car emits 4.6 metric tons per year. Comparing these values shows the carbon removed from the climate system each day of the bloom is equal to taking 7,500 cars off the road. Adjusting these values using the team’s highest measured rate of salp-mediated export (34 mg of C per day) increases the carbon offset to more than 28,000 vehicles.

    Moving forward, the team calls for increased recognition of the key role that salps play in global carbon export. “Blooms like the one we observed often go undetected,” says Steinberg, “and their contributions to the biological pump are rarely quantified, even in some of the best-studied regions of the world’s oceans.” Incorporation of salp dynamics into a recent carbon-cycle model illustrates the potential of salp-mediated export. In this global model, salps and other tunicates exported 700 million metric tons of carbon to the deep sea each year, equal to emissions from more than 150 million cars. 

    “Greater use of new technologies, such as adding video imaging systems to autonomous floats, would help detect these salp blooms,” says Steinberg. “Our study serves as a ‘call to arms’ to better detect and quantify these processes, using technology and sampling schemes that enable their inclusion in measurements and models of the biological carbon pump.”

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    Virginia Institute of Marine Science

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  • Researchers: Energy-efficient construction materials work better in colder climates

    Researchers: Energy-efficient construction materials work better in colder climates

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    Newswise — The researchers from Lithuania and Cyprus claim that the energy payback period of using phase change materials, new technology in the construction industry, is the shortest in a colder climate. The optimal location for their usage is the interior on the northern side of the building. The study provides informed answers regarding the application of PCMs to improve buildings’ energy efficiency.

    In recent years, phase change materials (PCMs) used to improve the energy efficiency of buildings are gaining momentum. PCMs can store and release large amounts of energy – when in a solid phase, they can absorb heat, providing a cooling effect and when a PCM is in its liquid phase it can release heat, providing a warming effect.

    “The ice melting to water is a phase change material, as is butter melting to oil. Why is it special? When material changes phase, it also absorbs and releases energy. In construction, these materials are encapsulated, i.e. the micro PCM capsules are integrated into a building element, such as concrete,” explains Paris Fokaides, a principal investigator at Kaunas University of Technology (KTU), Lithuania.

    Together with colleagues from Frederick University in Cyprus, KTU researchers were conducting a study in different European regions aiming to calculate the efficiency of the application of PCMs for the energy upgrade of the existing buildings. Their research revealed that the efficiency and energy payback period of PCM depends on certain conditions, such as the geographical location and the wall orientation of the building.

    “The thermal performance assessment of existing buildings is highly valuable information, which can be useful when making renovation decisions,” says Eglė Klumbytė, a researcher at KTU Faculty of Civil Engineering and Architecture, a co-author of the study.

    According to her, it is important to understand how and where to use the appropriate materials for maximum efficiency.

    In cold climates, the investments pay off in less than a year

    The work examines the application of PCM coatings in diverse meteorological conditions in Europe, for all major buildings’ orientations. In total, 16 numerical simulations were carried out for the four calendar months of January, April, July and October and for three latitudes of Athens, Milan and Copenhagen.

    “We wanted our research results to be globally applicable, that’s why we chose the locations with typical climatic conditions in Southern, Central and Northern Europe,” says Fokaides.

    The first 8 numerical simulations were performed with phase change material integrated into the building element structure and the other 8 simulations – in the absence of PCM. The PCM thickness incorporated was 4 cm. The annual energy saving was calculated for four typical months, representing the four seasons of the year (winter, spring, summer, and autumn).

    “One of the main study outcomes highlighted the fact that PCM performed better under cold conditions,” says Klumbytė.

    According to the researchers, this makes perfect sense – firstly, in colder conditions, PCM absorbs more energy, and secondly, since in colder climates the buildings use more energy (electricity, heating, etc.) the energy saving in these conditions is more efficient.

    “In the study, we have developed the energy payback period concept, which means the balance between the energy used to produce these materials and gained while using them. Energy payback period indicates how long it will take for the energy that is saved in the PCMs to eliminate the energy costs of their production,” explains Fokaides.

    The study revealed that PCM implementation can contribute to energy savings in certain cases, varying from 0.24 up to 29,84 kWh/m2a and energy payback periods from less than a year to almost 20 years. The longest energy payback period was calculated in warmer climates, and the shortest – in colder locations. The optimal orientation for placing PCMs is west and east in Athens, east and north in Milan, and north in Copenhagen. Also, PCMs work best when they are integrated into interior structures.

    Researched topics never discussed before

    “The developed numerical model demonstrates the ability to carry out a thermal assessment under diverse conditions with accurate results. The main goal of the European Union is sustainable environmental development. Our study can greatly contribute towards achieving this goal,” Klumbytė is convinced.

    According to Fokaides, the above-described study is researching topics that have not been discussed in scientific literature before. The optimal location of the phase change material in the building, its optimal orientation and the energy payback period are entirely new concepts in the broad theme of the energy performance of the built environment.

    “However, being a Greek, I cannot overlook the fact that the first description of an eco-friendly building was written by Socrates 2.5 thousand years ago. Back then, he indicated that the northern wall of a building needs to be thicker compared to the southern, thus our idea that wall orientation is crucial when considering its structural composition is related to that of Socrates,” says a KTU researcher.

    The KTU researchers claim that the methodology and dataset provided in this work can be used for further development of the buildings’ thermal assessment tools. Currently, the team is starting a new 1.5 million worth research project, which will focus on the digitalisation of the findings. This could include developing smart sensors to measure building elements’ thermal performance in real-time and other aspects. According to scientists, this topic has vast potential for commercialisation.

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    Kaunas University of Technology

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  • Western wildfires destroying more homes per square mile burned

    Western wildfires destroying more homes per square mile burned

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    Newswise — More than three times as many houses and other structures burned in Western wildfires in 2010-2020 than in the previous decade, and that wasn’t only because more acreage burned, a new analysis has found. Human ignitions started 76% of the wildfires that destroyed structures, and those fires tended to be in flammable areas where homes, commercial structures, and outbuildings are increasingly common. 

    “Humans are driving the negative impacts from wildfire,” concluded lead author Philip Higuera, a fire ecologist and professor at the University of Montana, who wrote the assessment during a sabbatical at the Cooperative Institute for Research in Environmental Sciences (CIRES) and CU Boulder. “Human fingerprints are all over this—we influence the when, the where, and the why.” 

    Most measures of wildfire’s impact—expansion of wildfire season into new months, and the number of structures in flammable vegetation, for example—are going in the wrong direction, Higuera said. But the new finding, published February 1 in the Proceedings of the National Academy of Sciences-Nexus, also means that human action can lessen the risks of wildfire damage.

    “We have levers,” he said. “As climate change makes vegetation more flammable we advise carefully considering if and how we develop in flammable vegetation, for example.” 

    During Higuera’s visiting fellowship at CIRES, he worked with several researchers to dig into the details of 15,001 Western wildfires between 1999 and 2020. 

    Burned area increased 30% across the West, the team found, but structure loss increased much more, by nearly 250%. Many factors contributed, including climate change, our tendency to build more homes in flammable ecosystems, and a history of suppressing wildfire. Co-author and CIRES/CU Boulder Ph.D. student Maxwell Cook said that the forcible removal of Indigenous people from landscapes played a role, by all-but-eliminating intentional burning, which can lessen the risk of more destructive fires.

    “Prescribed fire is an incredibly important tool, and we have a lot to learn about how people have been using fire for centuries,” Cook said. 

    In the new assessment, the team found some just plain horrible years for wildfire: 62% of all structures lost in those two decades were lost in just three years: 2017, 2018, and 2020, Cook said. And some states had it much worse than others: California, for example, accounted for more than 77% of all 85,014 structures destroyed during 1999-2020.  

    Across the West, 1.3 structures were destroyed for every 1,000 hectares of land scorched by wildfire between 1999 and 2009. Between 2010 and 2020, that ratio increased to 3.4. 

    Importantly, Higuera and his colleagues also found variability among states in how much burning occurred and how many structures were lost in wildfires. Colorado, for example, doesn’t burn that much relative to how much area could burn, but the state’s wildfires result in high structure losses. Here, wildfires were dominated by human-related ignitions late in the season and near structures and flammable vegetation. The 2021 Marshall Fire, too late to be included in this analysis, exemplifies this pattern, Higuera said.

    California also sees losses from wildfires, but burns much more overall. Each state could benefit from policies that address human-related ignitions, especially during late summer and fall and near developments, the paper concluded, and from policies that address fire-resistant building materials and consideration of nearby vegetation. 

    States like Montana, Nevada, and Idaho, by contrast, have large areas of less-developed land, so most wildfires burn from lightning ignitions and few destroy homes or buildings. Policies in these states could focus on maintaining safe landscape burning. 

    Finally, climate change mitigation is also essential, Higuera, Cook, and their co-authors concluded. Longer fire seasons—a result of climate change—mean that human-related ignitions are more consequential, leading to more destructive wildfires in the fall and early winter, for example, when they were once rare. 

    “Shifting social-ecological fire regimes explain increasing structure loss from Western wildfires” was co-authored by Higuera, Maxwell Cook, Jennifer Balch, Natasha Stavros, and Lise St. Dennis from CIRES Earth Lab, and Adam Mahood, now an ecologist with the Agricultural Research Service of the US Department of Agriculture in Fort Collins.

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    University of Colorado Boulder

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  • Tying past mass extinctions with low atmospheric CO2 is false

    Tying past mass extinctions with low atmospheric CO2 is false

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    Newswise — Attempts to discredit human-caused climate change by touting graphs of prehistoric atmospheric carbon dioxide and temperature changes are not something new. Peter Clack, an out-spoken climate change skeptic has once again tried to make a point that current atmospheric carbon dioxide levels are comparatively low compared to past eras. In this recent tweet, shared by thousands, Clack includes a graph from the work of Chris Scotese, an American geologist and paleogeographer, which shows that current levels of atmospheric carbon dioxide are relatively low compared to past events and that the only other time CO2 levels were this low was during the early Permian geological era, which spans 47 million years from the end of the Carboniferous Period 298.9 million years ago, to the beginning of the Triassic Period 251.9 million years ago. Clack mentions the “greatest extinction event in world history,” also known as the Permian Extinction as if this happened despite the low atmospheric CO2 recorded. However, most geological scientists contend that the Permian extinction occurred over the course of 15 million years during the latter part of the Permian Period (299 million to 252 million years ago).* Does this at all negate human-caused climate change that is happening in our own era? Of course not. In fact, this observation only backs the belief that a rise in global temperatures (and a sharp rise in CO2) impacts the living species on the planet. The main difference is that today’s fast rise in global temperatures can be prevented by the de-escalation of greenhouse gas emissions.

    The Permian extinction was characterized by the elimination of about 90 percent of the species on Earth. Although the exact cause of the mass extinction event has been debated in the past, a recent study from 2018 showed that the Permian mass extinction in the oceans was most likely caused by global warming that left animals unable to breathe. In fact, there was a steep rise of carbon dioxide in the atmosphere during the late Permian era, as the Scotese graph shows. Scientists believe that this was caused by considerable volcanic activity in present-day Siberia (tied to the dismantling of the supercontinent of Pangaea). This event points to rising CO2 and temperatures drastically affecting the biosphere.

    Chris Cramer, chief research officer at Underwriters Laboratories explains…

    The first and second graphs in this Tweet show that the first claim (600 million year minimum) and second claim (lowest global temperatures) are demonstrably false.

    Any relationship between the Permian extinction event and a local minimum in CO2 (relative to prior higher levels) simply shows how catastrophic it can be to living organisms when there is a significant change in CO2 levels, and associated temperatures, just as is happening right now with human activity driving CO2 above 400 ppm for the first time in millennia.

    Andrew Dessler, director of Texas Center for Climate Studies and professor of atmospheric sciences at Texas A&M also chimes in…

    So what’s wrong with this claim?  It suggests that low CO2 is the cause of the extinction.  I am not an expert on this, but I think the extinction has actually been linked to extensive volcanism that was occurring at about that same time.  In addition, 250 years ago the Earth had 280 ppm of CO2 in the atmosphere and the biosphere was doing just fine.  In fact, during the ice age (20,000 years ago), atmospheric CO2 was 180 ppm and the biosphere did OK.

    *https://www.britannica.com/science/Permian-extinction/Alteration-of-the-carbon-cycle

    Note to Journalists/Editors: The expert quotes are free to use in your relevant articles on this topic. Please attribute them to their proper sources.

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    Newswise

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  • Reducing anesthetics during surgery decreases greenhouse gases without affecting patient care, study shows

    Reducing anesthetics during surgery decreases greenhouse gases without affecting patient care, study shows

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    Newswise — ORLANDO, Fla. — Anesthesiologists can play a role in reducing the greenhouse gas emissions that contribute to global warming by decreasing the amount of anesthetic gas provided during procedures without compromising patient care, suggests new research being presented at the American Society of Anesthesiologists’ ADVANCE 2023, the Anesthesiology Business Event.

    Inhaled anesthetics used during general anesthesia are estimated to be responsible for 0.01% to 0.10% of the total worldwide carbon dioxide equivalent emission. For example, an hour of surgery using the inhaled anesthetic desflurane is equivalent to driving up to 470 miles, according to one study.1 Carbon dioxide is the primary greenhouse gas that traps heat in the Earth’s atmosphere, contributing to global warming.

     “Global warming is affecting our daily life more and more, and the reduction of greenhouse gas emissions has become crucial,” said Mohamed Fayed, M.D., M.Sc., lead author of the study and senior anesthesia resident at Henry Ford Health in Detroit. “No matter how small each effect is, it will add up. As anesthesiologists, we can contribute significantly to this cause by making little changes in our daily practice — such as lowering the flow of anesthetic gas — without affecting patient care.”

    While most general anesthesia procedures require high fresh gas flow (FGF) at the beginning and end of the procedure to achieve the desired effect quickly, it is safe and effective to lower the flow during the rest of the procedure, Dr. Fayed said. As part of the initiative to reduce FGF overall, the researchers educated anesthesiologists at their institution about the benefits of dialing down the anesthetic gas flow during the procedure, including through departmental presentations, newsletter articles, posters placed in work areas and emails. They also removed desflurane from their operating rooms because it produces the most significant carbon dioxide emissions from among the existing inhaled anesthetics.

    In the study of more than 13,000 patients, the authors set a goal of an average FGF of 3 liters per minute (L/min) or less for procedures. In March 2021, prior to the intervention, authors determined that FGF was 5-6 L/min in many cases, and only 65% of cases achieved an FGF of3 L/min or less. By July 2021, they recorded an average FGF of 3 L/min or less in 93% of cases. The researchers now are aiming to reduce the FGF to less than 2 L/min throughout the system.   

    The initiative is part of a quality improvement project called the Multicenter Perioperative Outcome Group, which includes more than 60 anesthesia practices. The ultimate goal is to measure actual carbon footprints from anesthetic agent waste for each surgical case, Dr. Fayed noted, but that will require significant modifications and costs.

    Provided through a mask, inhaled anesthetics such as desflurane, sevoflurane and isoflurane are given to patients during general anesthesia so that they are unconscious during a major operation, such as open-heart surgery. Another inhaled anesthetic, nitrous oxide, sometimes is given during childbirth or during dental procedures. Inhaled anesthetics are not used for patients who undergo sedation, which is typically used for minimally invasive procedures, such as colonoscopies. Nor is it used during regional anesthesia, which is used for childbirth or surgeries of the arm, leg or abdomen and numbs only part of the body with the patient remaining aware.

    “For a long time, there was a notion that the greenhouse effect caused in health care settings was an inevitable and unavoidable cost of providing patient care,” said Dr. Fayed. “But we have learned that reducing anesthetic gas flow is one of the many ways health care can lessen its contribution to the global warming crisis, along with reducing waste, turning off lights and equipment when not in use and challenging practice habits, as long as they don’t compromise patient care.”

    Masakatsu Nanamori, M.D., is the lead attending physician on the study.

    THE AMERICAN SOCIETY OF ANESTHESIOLOGISTS

    Founded in 1905, the American Society of Anesthesiologists (ASA) is an educational, research and scientific society with more than 56,000 members organized to raise and maintain the standards of the medical practice of anesthesiology. ASA is committed to ensuring physician anesthesiologists evaluate and supervise the medical care of patients before, during and after surgery to provide the highest quality and safest care every patient deserves.

    For more information on the field of anesthesiology, visit the American Society of Anesthesiologists online at asahq.org. To learn more about the role physician anesthesiologists play in ensuring patient safety, visit asahq.org/MadeforThisMoment. Like ASA on Facebook, follow ASALifeline on Twitter.

    1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3522493/#:~:text=Using%20desflurane%20for%201%20hour,driving%2C%20according%20to%20the%20study.&text=The%20optimal%20(lowest%20environmental%20impact,it%20would%20minimize%20anesthetic%20use

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    American Society of Anesthesiologists (ASA)

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  • Penguins, Robots, The Ocean and more

    Penguins, Robots, The Ocean and more

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    Newswise — Fieldwork in Antarctica is tricky, just ask University of Delaware scientist Matthew Breece. There is the 10-day trek to get there from Delaware, which includes a sometimes stomach-revolting four-day sail through Drake Passage, heavy research equipment to manage, limits on what you can pack. The temperatures are cool, averaging just above freezing at around 36 degrees Fahrenheit in the austral summer from October to February. Weather can change rapidly, too, relegating researchers indoors when conditions are poor and making for very long days in the field when conditions are pristine.

    But if you ask a scientist…or student…if the effort is worth it, the answer is a resounding YES!

    Marine biology students at Caesar Rodney High School in Camden, Delaware, got a firsthand look at what it’s like to conduct field research on penguins in Antarctica on Tuesday, Jan. 24, during a live video call with Matthew Breece, a research scientist in marine science and policy at the University of Delaware.

    “It’s fun, but also a lot of hard work,” said Breece, who guided the nearly 50 students through a virtual tour of Palmer Station, a United States research station situated on Anvers Island, Antarctica.

    Breece showed the students glaciers, laboratory experiments, research equipment and common areas, like the library, and shared stories and answered questions about living among wildlife including penguins, whales and seals. 

    “Wildlife have the right of way here,” said Breece, explaining how researchers were scrambling over rocks to get to their research vessels earlier in the week, while a crab-eater seal sunned itself on the boat dock. Gentoo penguins can swim 22 miles per hour, which is faster than the research boats can go, while Adélie penguins can only swim 10-12 mph.

    Breece and his colleagues are examining the feeding habits and predator-prey interactions of Adélie and Gentoo penguins in the region using an autonomous underwater vehicle (AUV). The AUV, called a REMUS, is equipped with a high-resolution echosounder that uses sonar to collect data about food resources that are available to marine animals in Palmer Deep Canyon on the West Antarctic Peninsula.

    Besides hearing from Breece, students also saw dramatic photographs from Antarctica and scientific charts used in the research.

    The new echosounder gives researchers a birds-eye view of what’s for lunch in the water. It was developed by Mark Moline, Maxwell P. and Mildred H. Harrington Professor of Marine Studies at UD and principal investigator on the project, and project co-PIs Kelly Benoit-Bird, senior scientist at Monterey Bay Aquarium Research Institute and Megan Cimino, assistant researcher at the Institute of Marine Sciences and assistant adjunct professor of ocean sciences at the University of California, Santa Cruz.

    “We switched to shorter wavelength frequencies to look at smaller things,” said Moline. “So, not only looking at the oceanography, but also the high-resolution food distribution of krill, copepods, fish and the species that eat them, like penguins.”

    The UD work complements the National Science Foundation’s ongoing Palmer Station Long-Term Ecological Research (LTER) study related to penguin population sizes and foraging ranges. The seabird component of the Palmer LTER research is led by Cimino, a UD alumna.

    Cimino has a second project with Carlos Moffat, a UD coastal physical oceanographer who also is in Antarctica serving as chief scientist of the Palmer LTER program, which has been collecting long-term ecological data for over 30 years. Collaborating institutions on the broader Palmer LTER study, led by Rutgers University and the Virginia Institute of Marine Science (VIMS), include researchers from UD, University of Virginia, Woods Hole Oceanographic Institution, University of Colorado, and University of California, Santa Cruz.

    Moffat also is conducting physical oceanography work as part of his NSF CAREER award to understand the dynamics of melting glaciers and how that impacts the ocean circulation and properties, such as salinity and temperature of the coastal ocean.

    “As the atmosphere is warming in this region of Antarctica, sea ice is decreasing and more glaciers are melting from the coast, physically changing the environment marine organisms are living in,” said Moffat. “One big question is what this means long term for marine organisms that live in these places, such as penguins, whales, seals and other wildlife. I see my contribution as trying to help them understand how the physical environment impacts the entire ecosystem.”

    From Antarctica to Delaware

    Lessons learned in Antarctica can help shed light on uncertainties about how sea level rise will evolve in other parts of the world, too. For instance, Delaware is a low-lying state with no area of the state more than eight miles from tidal waters. It is considered a big hotspot of sea level rise along the U.S. East Coast. And while sea levels are increasing on average around the world, due to ocean warming and melting ice from the continents, the distribution of sea level is very uneven. 

    “To understand what is going to happen in the future, we need to understand why sea levels are increasing and how it’s going to change over time,” said Moffat. “Antarctica is a good place to study this because change is happening very rapidly.”

    For most of the 20th century, the Palmer Station region was considered the fastest changing region in the southern hemisphere, while the Weddell Sea, which is located just around the corner of the Antarctic peninsula, had not changed as much. Over the last few years, researchers have begun to wonder whether the Weddell Sea has any influence on the West Antarctic Peninsula region or whether the regions are changing independently.

    To better understand these processes, Moffat’s team deployed two AUVs called gliders to sample the circulation close to the coast along the Antarctic peninsula, which is heavily influenced by the melting of glaciers. He and his students recovered oceanographic moorings that have been capturing data, such as water circulation currents, temperature and salinity, since early 2022. This is part of the West Antarctic Peninsula that has never been sampled before, so the team is eager to analyze the data.

    “I am particularly excited about the glider measurements, which I plan to add to my dissertation,” said Frederike (Rikki) Benz, a doctoral student in the Moffat lab. “It is especially interesting to be involved in the whole process from preparing, shipping and deploying to publishing.”

    Classrooms beyond campus

    For students, field research offers the opportunity for hands-on experience with sophisticated research instruments, data collection and analysis, troubleshooting and networking with researchers from other institutions. Sometimes those activities occur in remote regions of the world — like Antarctica.

    “The rarity of this experience comes with a sense of humility and responsibility to not take any moment for granted, a responsibility to ensure more opportunities are available for future students and scientists,” said Evan Quinter, who is pursuing a master’s degree in physical ocean science and engineering in the Moffat Lab.

    At Caesar Rodney High School, marine biology teachers Cristine Taylor and Sandra Ramsdell have just begun covering marine animals with their students. It is a fitting coincidence that made the live call with UD researchers both timely and meaningful.

    “Spending a day in class speaking with researchers was an awesome experience for our students,” said Taylor. “We are trying to encourage them to look at everything that goes into marine careers. Not every person is a marine biologist, there are computer scientists and engineers, ship captains and crew, and so many more people who can work in marine research.”

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    University of Delaware

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  • Comparing airfares instead of seat size fairer indicator of passenger carbon emissions

    Comparing airfares instead of seat size fairer indicator of passenger carbon emissions

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    Newswise — Allocating passenger aircraft emissions using airfares rather than travel class would give a more accurate idea of individual contributions, finds a study led by UCL.

    Emissions calculators base their estimates on travel class, assuming that someone travelling in a higher class and therefore taking up more space on the plane is responsible for more emissions.

    The study, published in Environmental Research Letters, describes how including airfares in calculations shows which passengers contribute the most revenue to the airline operating the aircraft, thereby allowing the plane to fly.

    Although in general, premium (business) seats are more expensive than economy, the researchers found when looking at data that many late bookings in economy class, often made for business trips or by high income travellers, cost as much as, or more than, premium seats.

    Lead author Dr Stijn van Ewijk (UCL Civil, Environmental & Geomatic Engineering) said: “The paper shows we should follow the money when calculating emissions of individual travellers, as it is revenue that decides whether an airline can operate a plane or not. Someone who has paid twice as much as a fellow traveller contributes twice as much to the revenue of the airline and should be allocated twice the emissions. The seat size of each travel class, which is currently used to allocate emissions, is only a rough approximation of how much passengers pay.”

    The researchers say that using airfares to calculate passenger emissions would benefit efforts to address climate change by encouraging people on all budgets to find alternative modes of transport where possible. It would also increase estimates of corporate emissions because it allocates more to expensive late bookings, which are often made for business purposes.

    Implementing a tax that is proportionate to the price of the ticket could make the total costs of flying fairer. People buying the most expensive tickets would pay the highest tax, encouraging them to seek alternatives.

    Whilst taxes differ between countries, typically the rates are the same across each travel class. Travellers buying expensive tickets, who are more likely to have higher incomes, pay a relatively low tax and are not currently discouraged from flying.

    Dr Van Ewijk added: “An equitable approach to reducing airline emissions should not just deter travellers who can only afford the cheapest early bookings but also the big spenders who bankroll the airline. By assigning emissions based on ticket prices, and taxing those emissions, we can make sure everyone pays their fair share, and is equally encouraged to look for alternatives.”

    A ticket tax should also take into account the distance flown and the model and age of plane, which can indicate how polluting it is.

    The authors used a dataset from the USA to test their fare-based allocation approach. They used the Airline Origin Survey database, which includes ticket fare data, origin and destination, travel class and fare per mile. From this, they calculated the distribution of ticket prices across all passengers on a typical flight.

    Based on the price distribution, the authors allocated emissions to passengers, and compared the results with estimates from widely used emissions calculators. Since ticket prices vary strongly by time of booking, the emissions per passenger varied too, far more than on the basis of seat size and travel class.

    Using an economic supply–demand model, the researchers estimated how a carbon tax on emissions would affect travellers, depending on whether the emissions the tax applied to were calculated from seat size and travel class, or the airfare. In all scenarios, a tax on emissions calculated from airfares had a more equitable effect because it reduced flying more evenly across income groups.

    The researchers hope to effect policy change in calculating and taxing passenger emissions, to ensure travellers on all budgets are encouraged to seek other forms of transport where possible or consider how essential the journey is.

     

    Notes to Editors

    Stijn van Ewijk, Shitiz Chaudhary, Peter Berrill; Estimating passenger emissions from airfares supports equitable climate action will be published in Environmental Research Letters on Wednesday 25th January, 12:00 UK time, 07:00 ET and is under a strict embargo until this time.

    The DOI for this paper will be 10.1088/1748-9326/acaa48

    Additional material

    Graphs and figures from the paper

    Credit: Dr Stijn Van Ewijk

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    University College London

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  • We need to learn to live with less steel

    We need to learn to live with less steel

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    Newswise — Steel is one of the most important materials in the world, integral to the cars we drive, the buildings we inhabit, and the infrastructure that allows us to travel from place to place. Steel is also responsible for 7% of global greenhouse gas emissions. In 2021, 45 countries made a commitment to pursue near-zero-emission steel in the next decade. But how possible is it to produce the steel we need in society with zero emissions?

    A new study focused on the Japanese steel industry shows that if we are truly committed to reaching zero emissions, we must be prepared for a scenario where the amount of steel we can produce is lower. Japan has set a target for a 46% reduction in emissions from steel by 2030, and zero emissions by 2050. So far, the roadmap for achieving this relies heavily on future innovations in technology. Hope is held out for developments in carbon capture and storage (CCS) and hydrogen-based technologies.

    In the study, Dr. Takuma Watari, a researcher at the National Institute for Environmental Studies, Japan, currently working with the University of Cambridge, argues that there is no silver bullet. He says that current plans to cut carbon emissions underestimate how difficult it will be to develop CCS and hydrogen technologies and deploy them widely: “These technologies still face serious technical, economic, and social challenges, and have yet to be implemented at scale. And importantly, it is highly uncertain whether there will be sufficient non-emitting electricity to use these technologies.” We need to confront the possibility that technological innovations might not be ready in time to allow us to maintain current levels of steel production whilst cutting emissions to zero.

    The research involved mapping the current flows of steel in Japan’s industry and using a model to explore how the industry might change if a strict carbon budget were applied in future. Dr. Watari explains that with current practice, the quantity and quality of steel produced would dramatically decrease under a zero-emission carbon budget. This is because of a lack of resources and the practice of downcycling, in which scraps of steel containing impurities are used to make new products. It is difficult to remove these impurities, so the new products have different quality and functionality from the original steel.

    According to Dr. Watari, “zero-emission steel production is possible by 2050, but in limited quantity and quality compared to current total production. This is due to the limited availability of zero-emission compatible resources and downcycling practices of scrap steel.”

    The research indicates that with a carbon budget of zero emissions, the production of steel goods would be dramatically restricted compared to today, reaching about half the current levels at best. In this case, higher-quality steel production (e.g., sheet steel) would be especially hard hit.

    The implication is clear. It is not enough to rely on a technological silver bullet materialising to transform the supply of steel. We also need to look seriously at strategies to reduce demand by shifting our culture of steel use and improving our material efficiency. We also need to pursue upcycling to produce high-grade steel from scrap steel.

    This will require collaboration from those who use steel as well as those who produce it. Steel products could be made more resource efficient if they are designed to last longer or to be lightweight. Once steel products reach the end of their life, upcycling could be achieved through advanced sorting and shredding to remove impurities from scrap steel. As a society, Japan may also have to become less steel-dependent and shift to a model of ‘service use’ rather than ownership of products. Unlike today, when steel is abundant and cheap, a net-zero future will require us to use scarcer, more expensive steel resources with greater efficiency.

    Dr. Watari concludes that we do need to invest in technological innovations, but we cannot simply wait for them to appear. Instead, steel users need to prepare for a world where there is less steel available: “We do not deny the need to invest in innovative production technologies. Rather, what we want to highlight is that we should look for far more strategic options, instead of simply relying on silver bullet production technologies. Placing material efficiency and upcycling at the heart of decarbonisation plans can reduce the over-reliance on innovative production technologies and prepare for the risk that these technologies may not scale up sufficiently in time.”

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    National Institute for Environmental Studies

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  • Family tree secrets: Island tree populations older, more diverse than expected

    Family tree secrets: Island tree populations older, more diverse than expected

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    Newswise — Tsukuba, Japan—It’s often assumed that island plant and animal populations are just the simple, fragile cousins of those on the mainland. But now, researchers from Japan have discovered that island populations may be a lot tougher and more complex than previously thought.

    In a recently published study, a research group led by the University of Tsukuba has revealed that the northernmost island populations of Siebold’s beech, Fagus crenata, are older and genetically more diverse than expected.

    Island and mainland populations often differ as a result of islands’ geographical isolation, which is often assumed to restrict the genetic diversity of their populations. However, a number of studies on land plants have shown that island populations have considerable genetic diversity despite their remoteness, indicating that the processes underlying their diversity are more complex than previously thought.

    “Although many island populations have existed for thousands of years or longer, the origins of some of them are still unknown,” says Professor Yoshiaki Tsuda, the main author of the study. “This includes Japan’s northernmost island populations of the native species F. crenata.”

    The research group investigated populations of F. crenata on Okushiri Island in the Japan Sea, which is thought to have broken away from the mainland in the Middle Pleistocene (the Ice Age, which occurred 2.58 million to 11,700 years ago), and remained separate ever since. The northward spread of this species began on the mainland approximately 6,000 years ago, after the last glacial maximum (LGM). The researchers studied the genetics of the island’s populations and those of nearby regions, and found that the island’s populations had high genetic diversity, and may not have arisen from a single colonization event.

    The Okushiri Island populations had a comparable number of private alleles (genetic sequences that are present in a single population and essentially absent in other populations) to the populations studied on nearby Hokkaido, which points to the existence of relict populations on Okushiri Island. A relict is a population of organisms that was more widespread or more diverse in the past in a restricted area.

    Taken together with palaeoecological and vegetation studies, as well as the island’s geology, these results indicate that F. crenata persisted in cryptic refugia (places where climatically sensitive species can survive regardless of incompatibility with the regional climate) on the island.

    “Our evidence indicates that populations of this species already existed on Okushiri Island prior to the LGM, and persisted there for longer than previously thought,” explains Professor Tsuda. The results of this study contribute to a growing body of evidence that island plant populations are more genetically diverse than previously estimated, which has implications for research and management of island species conservation, and the study of gene flow between island and mainland populations.

    ###
    This study was supported by JSPS KAKENHI (JP17K07852 and JP20K06152) and Core-to-Core Program (Asia-Africa Science Platforms: JPJSCCB20220007) from the Japan Society for the Promotion of Science and the 27th Pro Natura Fund Grant Program from the Pro Natura Foundation Japan.
     

    Original Paper

    The article, “Possible northern persistence of Siebold’s beech, Fagus crenata, at its northernmost distribution limit on an island in Japan Sea: Okushiri Island, Hokkaido,” was published in Frontiers in Plant Science at DOI: 10.3389/fpls.2022.990927

    Correspondence

    Associate Professor TSUDA Yoshiaki
    Faculty of Life and Environmental Sciences, University of Tsukuba

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    Faculty of Life and Environmental Sciences
    Sugadaira Research Station, Mountain Science Center

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  • Just one degree can change a species

    Just one degree can change a species

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    Newswise — It is not exactly a surprise that climate affects life on earth. At least major changes in climate make a difference. We know that not all species thrive everywhere on the planet.

    “The climate affects the life cycle of species, the number of individuals of a species, the overall number of species and the composition and distribution of species in an area,” says James D. M. Speed, a professor ​​in the Department of Natural History at the Norwegian University of Science and Technology’s (NTNU) University Museum.

    How small or large a change in temperature is needed to change any of this is less easy to estimate, however, and varies a lot from species to species. Some species thrive over a large and varied area, while others only thrive in very limited areas.

    Difficult to find answers

    Finding relevant answers can be difficult when looking at how the climate affects species. Researchers often investigate many different questions in a large geographical area. They may also use several different methods that make results from different surveys difficult to compare.

    These factors make it difficult or impossible to measure a local effect of climate change.

    Publication bias can also affect our overall impression. This bias happens when research results that show no effect – or perhaps even the opposite effect than is expected – are simply not published, and are thereby not available to other researchers. Getting a study published is easier when the results actually show an effect than when researchers find no change whatsoever.

    Thus, not all investigations are equally relevant, and it’s possible to fall into several traps.

    Examined local collection gathered over 250 years

    Researchers from several institutions, including the NTNU University Museum, found a helpful method to check how species in a specific area have been affected by temperatures over a longer period of time.

    “We used museum collections that have been built up over 250 years to measure the ecological response to climate change in central Norway,” says Speed. “We looked at a number of species, including vertebrates, invertebrates, plants and fungi.

    These museum collections are archives of the life in an area over a long period of time. But they are not just thousands of dead animals and plants for particularly interested collectors. They can actually give us valuable information about how the world is today and about how we can expect the world to be affected by climate change and the actions we humans choose to take.

    “What these data and the objects in the museum collections have in common is that studying climate change was not one of their purposes when they were collected. Only now are we seeing that the collections are relevant and that we can use them for such a purpose,” says Tommy Prestø, the senior engineer who is responsible for the day-to-day operation of the botanical collections at the NTNU University Museum.

    “It’s really interesting to be able to show that we can use the museum collections in new and innovative ways,” says Prestø, who has spent a lot of time making the collections accessible to a wider audience.

    Some of the results are very clear and show that even small changes can have quite a big impact.

    Sometimes one degree is enough

    For each degree the temperature rises, researchers find that:

    • The number of zooplankton decreases by almost 7700 individuals per cubic metre of water per degree warmer in Jonsvatnet, a lake in Trondheim.
    • The number of nesting birds is decreasing by two fewer breeding territories per square kilometre per degree warmer in Budalen in Trøndelag county.
    • Flowering plants bloom earlier throughout Trøndelag, on average two days earlier per degree warmer.

    When some species change, the life cycle of other species may change as well, for example species that eat zooplankton, birds or plants.

    “We can see a clear, regional connection with the climate,” says Speed.

    “For certain plant species, we’ve found that they’re flowering on average nine days earlier per century. This means that some of our plant species bloom three weeks earlier now than they did 250 years ago,” says Prestø.

    Stable species composition over time

    “But not everything changes with the climate. Some aspects of nature are more resilient. Overall, the distribution of species and species diversity stays stable over time. That surprised us,” says Speed.

    The fluctuations in the number of animals and species composition do not directly follow fluctuations in temperature, either. The relatively long period of 250 years can have both periods of warming and a stable climate.

    The species response may thus be delayed in relation to the changes in the climate. They could also be affected by other causes like changing land use, which is the biggest environmental problem, according to the International Nature Panel IPBES.

    Collections are a unique source for researchers

    These are insights we wouldn’t have gained without the fact that several generations of researchers, from botanist Bishop Gunnerus in the 1700s to the present day, had collected material and information about nature.

    “Natural history collections can provide unique insight into a wide range of ecological responses over a period of time that is much greater than what most ecological monitoring programmes manage. So the collections are an essential and invaluable source for ecological research over time,” says Speed.

    Reference: Speed, J. D. M., Evankow, A. M., Petersen, T. K., Ranke, P. S., Nilsen, N. H., Turner, G., Aagaard, K., Bakken, T., Davidsen, J. G., Dunshea, G., Finstad, A. G., Hassel, K., Husby, M., Hårsaker, K., Koksvik, J. I., Prestø, T., & Vange, V. (2022). A regionally coherent ecological fingerprint of climate change, evidenced from natural history collections. Ecology and Evolution, 12, e9471.

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    Norwegian University of Science and Technology (NTNU)

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  • Climate Change Likely to Uproot More Amazon Trees

    Climate Change Likely to Uproot More Amazon Trees

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    Newswise — Tropical forests are crucial for sucking up carbon dioxide from the atmosphere. But they’re also subject to intense storms that can cause “windthrow” – the uprooting or breaking of trees. These downed trees decompose, potentially turning a forest from a carbon sink into a carbon source.

    A new study finds that more extreme thunderstorms from climate change will likely cause a greater number of large windthrow events in the Amazon rainforest. This is one of the few ways that researchers have developed a link between storm conditions in the atmosphere and forest mortality on land, helping fill a major gap in models.

    “Building this link between atmospheric dynamics and damage at the surface is very important across the board,” said Jeff Chambers, a senior faculty scientist at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), and director of the Next Generation Ecosystem Experiments (NGEE)-Tropics project, which performed the research. “It’s not just for the tropics. It’s high-latitude, low-latitude, temperate-latitude, here in the U.S.”

    Researchers found that the Amazon will likely experience 43% more large blowdown events (of 25,000 square meters or more) by the end of the century. The area of the Amazon likely to see extreme storms that trigger large windthrows will also increase by about 50%. The study was published in the journal Nature Communications on Jan. 6.

    “We want to know what these extreme storms and windthrows mean in terms of the carbon budget and carbon dynamics, and for carbon sinks in the forests,” Chambers said. While downed trees slowly release carbon as they decompose, the open forest becomes host to new plants that pull carbon dioxide from the air. “It’s a complicated system, and there are still a lot of pieces of the puzzle that we’re working on. In order to answer the question more quantitatively, we need to build out the land-atmosphere links in Earth system models.”  

    To find the link between air and land, researchers compared a map of more than 1,000 large windthrows with atmospheric data. They found that a measurement known as CAPE, the “convective available potential energy,” was a good predictor of major blowdowns. CAPE measures the amount of energy available to move parcels of air vertically, and a high value of CAPE often leads to thunderstorms. More extreme storms can come with intense vertical winds, heavy rains or hail, and lightning, which interact with trees from the canopy down to the soil.

    “Storms account for over half of the forest mortality in the Amazon,” said Yanlei Feng, first author on the paper. “Climate change has a lot of impact on Amazon forests, but so far, a large fraction of the research focus has been on drought and fire. We hope our research brings more attention to extreme storms and improves our models to work under a changing environment from climate change.”

    While this study looked at a future with high carbon emissions (a scenario known as SSP-585), scientists could use projected CAPE data to explore windthrow impacts in different emissions scenarios. Researchers are now working to integrate the new forest-storm relationship into Earth system models. Better models will help scientists explore how forests will respond to a warmer future – and whether they can continue to siphon carbon out of the atmosphere or will instead become a contributor.

    “This was a very impactful climate change study for me,” said Feng, who completed the research as a graduate student researcher in the NGEE-Tropics project at Berkeley Lab. She now studies carbon capture and storage at the Carnegie Institution for Science at Stanford University. “I’m worried about the projected increase in forest disturbances in our study and I hope I can help limit climate change. So now I’m working on climate change solutions.” 

    NGEE-Tropics is a ten-year, multi-institutional project funded by the U.S. Department of Energy’s Office of Science, Office of Biological and Environmental Research.

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    Founded in 1931 on the belief that the biggest scientific challenges are best addressed by teams, Lawrence Berkeley National Laboratory and its scientists have been recognized with 16 Nobel Prizes. Today, Berkeley Lab researchers develop sustainable energy and environmental solutions, create useful new materials, advance the frontiers of computing, and probe the mysteries of life, matter, and the universe. Scientists from around the world rely on the Lab’s facilities for their own discovery science. Berkeley Lab is a multiprogram national laboratory, managed by the University of California for the U.S. Department of Energy’s Office of Science.

    DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.

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  • NASA says 2022 fifth warmest year on record, warming trend continues

    NASA says 2022 fifth warmest year on record, warming trend continues

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    Newswise — Earth’s average surface temperature in 2022 tied with 2015 as the fifth warmest on record, according to an analysis by NASA. Continuing the planet’s long-term warming trend, global temperatures in 2022 were 1.6 degrees Fahrenheit (0.89 degrees Celsius) above the average for NASA’s baseline period (1951-1980), scientists from NASA’s Goddard Institute for Space Studies (GISS) in New York reported.

    “This warming trend is alarming,” said NASA Administrator Bill Nelson. “Our warming climate is already making a mark: Forest fires are intensifying; hurricanes are getting stronger; droughts are wreaking havoc and sea levels are rising. NASA is deepening our commitment to do our part in addressing climate change. Our Earth System Observatory will provide state-of-the-art data to support our climate modeling, analysis and predictions to help humanity confront our planet’s changing climate.”

    The past nine years have been the warmest years since modern recordkeeping began in 1880. This means Earth in 2022 was about 2 degrees Fahrenheit (or about 1.11 degrees Celsius) warmer than the late 19th century average.

    “The reason for the warming trend is that human activities continue to pump enormous amounts of greenhouse gases into the atmosphere, and the long-term planetary impacts will also continue,” said Gavin Schmidt, director of GISS, NASA’s leading center for climate modeling.

    Human-driven greenhouse gas emissions have rebounded following a short-lived dip in 2020 due to the COVID-19 pandemic. Recently, NASA scientists, as well as international scientists, determined carbon dioxide emissions were the highest on record in 2022. NASA also identified some super-emitters of methane – another powerful greenhouse gas – using the Earth Surface Mineral Dust Source Investigation instrument that launched to the International Space Station last year.

    The Arctic region continues to experience the strongest warming trends – close to four times the global average – according to GISS research presented at the 2022 annual meeting of the American Geophysical Union, as well as a separate study.

    Communities around the world are experiencing impacts scientists see as connected to the warming atmosphere and ocean. Climate change has intensified rainfall and tropical storms, deepened the severity of droughts, and increased the impact of storm surges. Last year brought torrential monsoon rains that devastated Pakistan and a persistent megadrought in the U.S. Southwest. In September, Hurricane Ian became one of the strongest and costliest hurricanes to strike the continental U.S.  

    Tracking Our Changing Planet

    NASA’s global temperature analysis is drawn from data collected by weather stations and Antarctic research stations, as well as instruments mounted on ships and ocean buoys. NASA scientists analyze these measurements to account for uncertainties in the data and to maintain consistent methods for calculating global average surface temperature differences for every year. These ground-based measurements of surface temperature are consistent with satellite data collected since 2002 by the Atmospheric Infrared Sounder on NASA’s Aqua satellite and with other estimates.

    NASA uses the period from 1951-1980 as a baseline to understand how global temperatures change over time. That baseline includes climate patterns such as La Niña and El Niño, as well as unusually hot or cold years due to other factors, ensuring it encompasses natural variations in Earth’s temperature.

    Many factors can affect the average temperature in any given year. For example, 2022 was one of the warmest on record despite a third consecutive year of La Niña conditions in the tropical Pacific Ocean. NASA scientists estimate that La Niña’s cooling influence may have lowered global temperatures slightly (about 0.11 degrees Fahrenheit or 0.06 degrees Celsius) from what the average would have been under more typical ocean conditions.

    A separate, independent analysis by the National Oceanic and Atmospheric Administration (NOAA) concluded that the global surface temperature for 2022 was the sixth highest since 1880. NOAA scientists use much of the same raw temperature data in their analysis and have a different baseline period (1901-2000) and methodology. Although rankings for specific years can differ slightly between the records, they are in broad agreement and both reflect ongoing long-term warming.

    NASA’s full dataset of global surface temperatures through 2022, as well as full details with code of how NASA scientists conducted the analysis, are publicly available from GISS.

    GISS is a NASA laboratory managed by the Earth Sciences Division of the agency’s Goddard Space Flight Center in Greenbelt, Maryland. The laboratory is affiliated with Columbia University’s Earth Institute and School of Engineering and Applied Science in New York.

    For more information about NASA’s Earth science programs, visit: 

    https://www.nasa.gov/earth

     

     -end-

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    NASA Goddard Space Flight Center

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  • UAlbany Meteorologist Available to Discuss California Storms

    UAlbany Meteorologist Available to Discuss California Storms

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    Newswise — ALBANY, N.Y. – A series of strong storm systems known as “atmospheric rivers” have dumped massive amounts of rain and snow on California since late December, producing deadly flooding, mudslides, severe thunderstorms and tornadoes.

    California officials reported on Tuesday that the storms have claimed the lives of at least 17 people, which is more than the death toll of wildfires in the region over the past two years combined. More severe weather is expected to hit this weekend.

    Ryan Torn, chair and professor at the University at Albany’s Department of Atmospheric and Environmental Sciences, is an expert on atmospheric predictability and numerical weather prediction (NWP) models. Currently, he’s leading research in collaboration with the Center for Western Weather and Water Extremes that seeks to improve our ability to predict atmospheric rivers along the U.S. West Coast, including where to take additional observations to reduce forecast uncertainty.  

    The goal is to develop and test targeted airborne and buoy observations over the Northeast Pacific to improve forecasts of where atmospheric rivers will make landfall, and their potential impacts, with lead times of at least one to five days.

    “The recent heavy precipitation has helped alleviate some of the multi-year drought for California, yet the precipitation has come too quickly to avoid some of the hazardous impacts, like river flooding and mudslides,” Torn said. “Thankfully, advancements in past and current research of atmospheric rivers have improved our ability to forecast these events, often several days in advance.”

    Torn is available for phone or live/taped interviews. UAlbany also has an on-campus television studio for satellite interviews.

    About the University at Albany:

    A comprehensive public research university, the University at Albany-SUNY offers more than 120 undergraduate majors and minors and 125 master’s, doctoral and graduate certificate programs. As a Carnegie-classified R1 institution, signifying the highest level of doctoral and research activity, UAlbany is a leader among New York colleges and universities in diverse fields like atmospheric and environmental sciences, business, education, public health, health sciences, criminal justice, emergency preparedness, engineering and applied sciences, informatics, public administration, social welfare and sociology, taught by an extensive roster of faculty experts. It also offers expanded academic and research opportunities for students through an affiliation with Albany Law School. With a curriculum enhanced by 600 study-abroad opportunities, UAlbany launches great careers.

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    University at Albany, State University of New York

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  • Loss of glaciers faster than expected

    Loss of glaciers faster than expected

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    Newswise — How will our glaciers change during the 21st century? In a new study whose findings are published in Science (5 January), an international team1, including scientists from the CNRS and Université Toulouse III–Paul Sabatier, has demonstrated a loss of glacial mass greater than earlier projected—and specifically, 11% to 44% higher than estimates used in the most recent IPCC report. Small glaciers (<1 km2) predominate on our planet, and they are the most impacted by mass loss. In the scenario where global warming is limited to 1.5 °C, 49% of the world’s glaciers, the majority of the small ones , are expected to disappear by 2100, prompting a 9-cm sea level rise. The largest glaciers would also be affected but would not disappear. If, on the other hand, temperatures rise by 4 °C, neither small nor large glaciers will be spared: 83% would disappear and there would be a 15.4-cm sea level rise. To reach their conclusions, the team of scientists relied on the observations of a study that quantified widespread, accelerated glacial mass loss around the world between 2000 and 2019. These earlier data allowed them to calibrate their mathematical model, developed especially for the work presented in their publication, for each and every one of the >215 thousand glaciers on Earth. The model also accounts for processes not previously represented, such as mass loss due to iceberg calving and the effect of a layer of debris on the surface of a glacier. Shrinkage of the greatest glaciers, like those in Alaska, the Canadian Arctic, and around Antarctica, key to future sea level rise, may still be limited if we implement measures to mitigate global warming.

    1In France, this study incluted scientists from the Laboratoire d’étude en géophysique et océanographie spatiales (CNRS/CNES/IRD/Université Paul Sabatier Toulouse III).

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    CNRS (Centre National de Recherche Scientifique / National Center of Scientific Research)

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  • Fathoming the hidden heatwaves that threaten coral reefs

    Fathoming the hidden heatwaves that threaten coral reefs

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    Newswise —   In April to May 2019, the coral reefs near the French Polynesian island of Moorea in the central South Pacific Ocean suffered severe and prolonged thermal bleaching. The catastrophe occurred despite the absence of El Niño conditions that year, intriguing ocean scientists around the world.

        An international research team led by Prof. Alex WYATT of the Department of Ocean Science at The Hong Kong University of Science and Technology, has investigated this surprising and paradoxical coral bleaching episode. The unexpected event was related to the passage of anti-cyclonic eddies that elevated sea levels and concentrated hot water over the reef, leading to an underwater marine heatwave that was largely hidden from view at the surface. The findings have recently been published in Nature Communications.  

        Most studies of coral bleaching patterns rely on sea-surface measures of water temperatures, which cannot capture the full picture of threats from ocean heating to marine ecosystems, including tropical coral reefs. These surface measurements conducted over broad areas with satellites are valuable, yet are unable to detect heating below the surface that influences communities living in waters deeper that the shallowest few metres of the ocean.

        Prof. Wyatt and colleagues analyzed data collected at Moorea over 15 years from 2005 to 2019, taking advantage of a rare combination of remotely sensed sea-surface temperatures and high-resolution, long-term in-situ temperatures and sea level anomalies. Results showed that the passage of anti-cyclonic eddies in the open ocean past the island raised sea levels and pushed internal waves down into deeper water. Internal waves travel along the interface between the warm surface layer of the ocean and cooler layers below, and, in a previous study also led by Prof. Wyatt, have been shown to provide frequent cooling of coral reef habitats. The present research shows that, as a result of the anti-cyclones, internal wave cooling was shut down in early 2019, as well as during some earlier heatwaves.  This led to unexpected heating over the reef, which in turn caused large-scale coral bleaching and subsequent mortality. Unfortunately for local reef biodiversity, the extensive coral death in 2019 has offset the recovery of coral communities that had been occurring around Moorea for the last decade.

        A notable observation, in contrast to the 2019 heatwave, was that the reefs in Moorea did not undergo significant bleaching mortality in 2016, despite the prevailing super El Niño that brought warm conditions and decimated many shallow reefs worldwide. The new research demonstrates the importance of collecting temperature data across the range of depths that coral reefs occupy because the capacity to predict coral bleaching can be lost with a focus only on surface conditions. Sea-surface temperature data would predict moderate bleaching in both 2016 and 2019 at Moorea. However, direct observations showed that there was only ecologically insignificant bleaching in 2016, with heating that was short in duration and restricted to shallow depths. The severe and prolonged marine heatwave in 2019 would have been overlooked if researchers only had access to sea-surface temperature data, and the resulting catastrophic coral bleaching may have been incorrectly ascribed to causes other than heating.

        “The present study highlights the need to consider environmental dynamics across depths relevant to threatened ecosystems, including those due to the passage of underwater ocean weather events.  This kind of analysis depends on long-term, in situ data measured across ocean depths, but such data is generally lacking,” Prof. Wyatt said.  

        “Our paper provides a valuable mechanistic example for assessing the future of coastal ecosystems in the context of changing ocean dynamics and climates.”

        This HKUST-led research was conducted in collaboration with a team of scientists from Scripps Institution of Oceanography at the University of California San Diego, the University of California Santa Barbara, California State University, Northbridge, and Florida State University. The data underlying this study were made possible by coupled long-term physical and ecological observations conducted at the Moorea Coral Reef Long-Term Ecological Research (LTER) site. The long-term analyses conducted here, and the concurrent monitoring of physical conditions and biological dynamics across the full range of depths of island and coastal marine communities, is a model for future research that aims to protect vulnerable living resources in the ocean. 

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    Hong Kong University of Science and Technology

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  • How climate change impacts the Indian Ocean dipole, leading to severe droughts and floods

    How climate change impacts the Indian Ocean dipole, leading to severe droughts and floods

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    Newswise — PROVIDENCE, R.I. [Brown University] — With a new analysis of long-term climate data, researchers say they now have a much better understanding of how climate change can impact and cause sea water temperatures on one side of the Indian Ocean to be so much warmer or cooler than the temperatures on the other — a phenomenon that can lead to sometimes deadly weather-related events like megadroughts in East Africa and severe flooding in Indonesia.

    The analysis, described in a new study in Science Advances by an international team of scientists led by researchers from Brown University, compares 10,000 years of past climate conditions reconstructed from different sets of geological records to simulations from an advanced climate model.

    The findings show that about 18,000 to 15,000 years ago, as a result of melted freshwater from the massive glacier that once covered much of North America pouring into the North Atlantic, ocean currents that kept the Atlantic Ocean warm weakened, setting off a chain of events in response. The weakening of the system ultimately led to the strengthening of an atmospheric loop in the Indian Ocean that keeps warmer water on one side and cooler water on the other.

    This extreme weather pattern, known as a dipole, prompts one side (either east or west) to have higher-than-average rainfall and the other to have widespread drought. The researchers saw examples of this pattern in both the historical data they studied and the model’s simulation. They say the findings can help scientists not only better understand the mechanisms behind the east-west dipole in the Indian Ocean, but can one day help to produce more effective forecasts of drought and flood in the region.

    “We know that in the present-day gradients in the temperature of the Indian Ocean are important to rainfall and drought patterns, especially in East Africa, but it’s been challenging to show that those gradients change on long time-scales and to link them to long-term rainfall and drought patterns on both sides of the Indian Ocean,” said James Russell, a study author and professor of Earth, environmental, and planetary sciences at Brown. “We now have a mechanistic basis to understand why some of the longer-term changes in rainfall patterns in the two regions have changed through time.”

    In the paper, the researchers explain the mechanisms behind how the Indian Ocean dipole they studied formed and the weather-related events it led to during the period they looked at, which covered the end of the last Ice Age and the start of the current geological epoch.

    The researchers characterize the dipole as an east-west dipole where the water on the western side — which borders modern day East African countries like Kenya, Ethiopia and Somalia — is cooler than the water on eastern side toward Indonesia. They saw that the warmer water conditions of the dipole brought greater rainfall to Indonesia, while the cooler water brought much drier weather to East Africa.

    That fits into what is often seen in recent Indian Ocean dipole events. In October, for example, heavy rain led to floods and landslides in Indonesian islands of Java and Sulawesi, leaving four people dead and impacting over 30,000 people. On the opposite end, Ethiopia, Kenya and Somalia experienced intense droughts starting in 2020 that threatened to cause famine.

    The changes the authors observed 17,000 years ago were even more extreme, including the complete drying of Lake Victoria — one of the largest lakes on Earth.

    “Essentially, the dipole intensifies dry conditions and wet conditions that could result in extreme events like multi-year or decades-long dry events in East Africa and flooding events in South Indonesia,” said Xiaojing Du, a Voss postdoctoral researcher in the Institute at Brown for Environment and Society and Brown’s Department of Earth, Environmental and Planetary Sciences, and the study’s lead author. “These are events that impact people’s lives and also agriculture in those regions. Understanding the dipole can help us better predict and better prepare for future climate change.”

    The dipole the researchers studied formed from the interactions between the heat transport system of the Atlantic Ocean and an atmospheric loop, called a Walker Circulation, in the tropical Indian Ocean. The lower part of the atmospheric loop flows east to west across much of the region at low altitudes near the ocean surface, and the upper part flows west to east at higher altitudes. The higher air and lower air connect in one big loop.

    Interruption and weakening of the Atlantic Ocean heat transport, which works like a conveyor belt made of ocean and wind currents, was brought on by massive melting of the Laurentide ice sheet that once covered most of Canada and the northern U.S. The melting cooled the Atlantic and consequent wind anomalies triggered the atmospheric loop over the tropical Indian Ocean to become more active and extreme. That then led to increased precipitation in the east side of the Indian Ocean (where Indonesia sits) and reduced precipitation in the west side, where East Africa sits.

    The researchers also show that during the period they studied, this effect was amplified by a lower sea level and the exposure of nearby continental shelves.

    The scientists say more research is needed to figure out exactly what effect the exposed continental shelf and lower sea level has on the Indian Ocean’s east-west dipole, but they’re already planning to expand the work to investigate the question. While this line of the work on lower sea levels won’t play into modeling future conditions, the work they’ve done investigating how the melting of ancient glaciers impacts the Indian Ocean dipole and the heat transport system of the Atlantic Ocean may provide key insights into future changes as climate change brings about more melting.

    “Greenland is currently melting so fast that it’s discharging a lot of freshwater into the North Atlantic Ocean in ways that are impacting the ocean circulation,” Russell said. “The work done here has provided a new understanding of how changes in the Atlantic Ocean circulation can impact Indian Ocean climate and through that rainfall in Africa and Indonesia.”

    The study was supported with funding from the Institute at Brown for Environment and Society and the National Science Foundation.

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    Brown University

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  • How do tidal marshes store carbon?

    How do tidal marshes store carbon?

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    Newswise — January 2, 2023 – Tidal marshes are wetlands that are covered with incoming tidal water twice a day. These marshes may be as small as narrow fringe along a tidal creek or miles across in estuaries with adjacent flat landscapes. There are nearly 40 million acres of tidal marshes along the Atlantic, Gulf, and Pacific shores of the US. The Soil Science Society of America’s (SSSA) January 1st Soils Matter blog explores how tidal marshes store carbon and why they are an important part of surrounding landscapes.

    Tidal marshes are also common in many estuaries such as the Chesapeake Bay and along rivers that enter these coastal estuaries. Tidal marshes are some of the most productive ecosystems on the planet. They are an important part of the landscapes because they provide flood protection, erosion control, wildlife food & habitat, water quality support, and many other benefits.

    Comparative to forest soils (that hold about 65% of the carbon held in a forest, with the rest of the carbon stored in plant life), tidal marshes store 3 to 5 times that amount in the soil.

    But why do tidal marshes store so much more carbon?

    According to Dr. Mark Stolt of University of Rhode Island, there are two major factors – the plant life, and the soil conditions.

    Marsh grasses and shrubs are drenched with full sunlight and the soils are rich in nutrients. This results in prolific plant growth above the ground. There is also growth below the ground in the form of roots and rhizomes. Marsh plants thrive in saturated conditions.

    Tidal waters that flood marshes bring in organic matter via sediment that is suspended in the flooding waters. That carbon-rich sediment is trapped by the marsh grasses. It settles to the bottom becoming part of the marsh peat.

    With twice-daily flooding, the soils are constantly under water, or saturated. Because the soil is under water, soil microbial activity is inhibited by the limited amount of oxygen. Without oxygen, soil microbes can’t decompose organic matter as well as oxygen-rich environments. This is the big reason why tidal marshes can accumulate much more carbon than forest soils.

    To read the entire blog please visit: https://soilsmatter.wordpress.com/2023/01/01/how-do-tidal-marshes-store-carbon/

    Follow SSSA on Facebook at https://www.facebook.com/SSSA.soils, Twitter at SSSA_Soils. SSSA has soils information on www.soils.org/discover-soils, for teachers at www.soils4teachers.org, and for students through 12th grade, www.soils4kids.org.

    The Soil Science Society of America (SSSA) is a progressive international scientific society that fosters the transfer of knowledge and practices to sustain global soils. Based in Madison, WI, and founded in 1936, SSSA is the professional home for 6,000+ members and 1,000+ certified professionals dedicated to advancing the field of soil science. The Society provides information about soils in relation to crop production, environmental quality, ecosystem sustainability, bioremediation, waste management, recycling, and wise land use.

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    American Society of Agronomy (ASA), Crop Science Society of America (CSSA), Soil Science Society of America (SSSA)

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  • South Asian Black carbon aerosols accelerate loss of glacial mass over the Tibetan plateau

    South Asian Black carbon aerosols accelerate loss of glacial mass over the Tibetan plateau

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    Newswise — Black carbon aerosols are produced by the incomplete combustion of fossil fuels and biomass, and are characterized by strong light absorption. Black carbon deposition in snow/ice reduces the albedo of snow/ice surfaces, which may accelerate the melting of glaciers and snow cover, thus changing the hydrological process and water resources in the region.

    The South Asia region adjacent to the Tibetan Plateau has among the highest levels of black carbon emission in the world. Many studies have emphasized black carbon aerosols from South Asia can be transported across the Himalayan Mountains to the inland region of the Tibetan Plateau.

    Recently, a joint research team led by Prof. KANG Shichang from the Northwest Institute of Eco-Environment and Resources of the Chinese Academy of Sciences (CAS), Prof. CHEN Deliang from the University of Gothenburg, and Prof. Robert Gillies from Utah State University analyzed the influence of black carbon aerosols on regional precipitation and glaciers over the Qinghai-Tibet Plateau.

    Their findings were published in Nature Communications on Nov. 30.

    The researchers found that since the 21st century, South Asian black carbon aerosols have indirectly affected the mass gain of the Tibetan Plateau glaciers by changing long-range water vapor transport from the South Asian monsoon region.

    “Black carbon aerosols in South Asia heat up the middle and upper atmosphere, thus increasing the North­–South temperature gradient,” said Prof. KANG. “Accordingly, the convective activity in South Asia is enhanced, which causes convergence of water vapor in South Asia. Meanwhile, black carbon also increases the number of cloud condensation nuclei in the atmosphere.”

    These changes in meteorological conditions caused by black carbon aerosols make more water vapor form precipitation in South Asia, and the northward transport to the Tibetan Plateau was weakened. As a result, precipitation in the central and the southern Tibetan Plateau decreases during the monsoon, especially in the southern Tibetan Plateau.

    The decrease in precipitation further leads to a decrease of mass gain of glaciers. From 2007 to 2016, the reduced mass gain by precipitation decrease accounted for 11.0% of the average glacier mass loss on the Tibetan Plateau and 22.1% in the Himalayas.

    “The transboundary transport and deposition of black carbon aerosols from South Asia accelerate glacier ablation over the Tibetan Plateau. Meanwhile, the reduction of summer precipitation over the Tibetan Plateau will reduce the mass gain of plateau glaciers, which will increase the amount of glacier mass deficit,” said Prof. KANG.

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    Chinese Academy of Sciences

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  • Bering Land Bridge formed surprisingly late during last ice age

    Bering Land Bridge formed surprisingly late during last ice age

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    Newswise — A new study shows that the Bering Land Bridge, the strip of land that once connected Asia to Alaska, emerged far later during the last ice age than previously thought. 

    The unexpected findings shorten the window of time that humans could have first migrated from Asia to the Americas across the Bering Land Bridge. 

    The findings also indicate that there may be a less direct relationship between climate and global ice volume than scientists had thought, casting into doubt some explanations for the chain of events that causes ice age cycles. The study was published on December 27 in the Proceedings of the National Academy of Sciences. 

    “This result came totally out of left field,” said Jesse Farmer, postdoctoral researcher at Princeton University and co-lead author on the study. “As it turns out, our research into sediments from the bottom of the Arctic Ocean told us not only about past climate change but also one of the great migrations in human history.”

    Insight into ice age cycles 

    During the periodic ice ages over Earth’s history, global sea levels drop as more and more of Earth’s water becomes locked up in massive ice sheets. At the end of each ice age, as temperatures increase, ice sheets melt and sea levels rise. These ice age cycles repeat throughout the last 3 million years of Earth’s history, but their causes have been hard to pin down.

    By reconstructing the history of the Arctic Ocean over the last 50,000 years, the researchers revealed that the growth of the ice sheets — and the resulting drop in sea level — occurred surprisingly quickly and much later in the last glacial cycle than previous studies had suggested.

    “One implication is that ice sheets can change more rapidly than previously thought,” Farmer said.

    During the last ice age’s peak of the last ice age, known as the Last Glacial Maximum, the low sea levels exposed a vast land area that extended between Siberia and Alaska known as Beringia, which included the Bering Land Bridge. In its place today is a passage of water known as the Bering Strait, which connects the Pacific and Arctic Oceans.

    Based on records of estimated global temperature and sea level, scientists thought the Bering Land Bridge emerged around 70,000 years ago, long before the Last Glacial Maximum.

    But the new data show that sea levels became low enough for the land bridge to appear only 35,700 years ago. This finding was particularly surprising because global temperatures were relatively stable at the time of the fall in sea level, raising questions about the correlation between temperature, sea level and ice volume.

    “Remarkably, the data suggest that the ice sheets can change in response to more than just global climate,” Farmer said. For example, the change in ice volume may have been the direct result of changes in the intensity of sunlight that struck the ice surface over the summer.

    “These findings appear to poke a hole in our current understanding of how past ice sheets interacted with the rest of the climate system, including the greenhouse effect,” said Daniel Sigman, Dusenbury Professor of Geological and Geophysical Sciences at Princeton University and Farmer’s postdoctoral advisor. “Our next goal is to extend this record further back in time to see if the same tendencies apply to other major ice sheet changes. The scientific community will be hungry for confirmation.”

    New context for human migration

    The timing of human migration into North America from Asia remains unresolved, but genetic studies tell us that ancestral Native American populations diverged from Asian populations about 36,000 years ago, the same time that Farmer and colleagues found that the Bering Land Bridge emerged.

    “It’s generally believed that the land bridge was open for a while, and then humans crossed it at some point,” Sigman said. “But our new data suggest that the land bridge was not open, and as soon as it opened up, human populations made their way into North America.”

    The finding raises questions about why humans decided to migrate as soon as the land bridge opened, and how humans made their way across the land bridge with no previous knowledge of the landscape.

    The researchers noted that they need to be cautious when considering these implications, as the interpretation requires combining very different types of information, including the new data and the information of human geneticists and paleoanthropologists. They look forward to seeing how their results are built upon by these other scientific communities.

    A window to the past

    To reconstruct the history of the Bering Strait, Farmer and Sigman sought an ocean chemical fingerprint.

    Pacific waters carry high concentrations of nitrogen molecules that have a distinct chemical composition, known as an isotope ratio. Today, waters from the Pacific Ocean travel northwards across the Bering Strait into the Arctic Ocean, carrying a traceable nitrogen isotope ratio.

    By measuring nitrogen isotopes in sediments at the bottom of the Arctic Ocean, Farmer found that the fingerprint of Pacific Ocean nitrogen disappeared when the Bering Strait was closed during the peak of the last ice age, as expected.

    But when Farmer continued his analyses further back in time – to about 50,000 years ago – he found that the Pacific nitrogen fingerprint returned far more recently than researchers had thought possible.

    “When Jesse showed me his data, he didn’t need to explain to me what had happened,” Sigman said. “It was too large of a change to be anything other than a previous opening of the Bering Strait.”

    To understand the implications for global sea level, Farmer and Sigman collaborated with Tamara Pico, a sea level expert and professor of Earth and Planetary Sciences at UC Santa Cruz, Princeton undergraduate Class of 2014, and co-lead author on the paper. Pico compared Farmer’s results with sea level models based on different scenarios for the growth of the ice sheets.

    “When Jesse contacted me I was so excited,” Pico said. “A large part of my PhD thesis was focused on how fast global ice sheets grew leading into the Last Glacial Maximum, and much of my work suggests that they might have grown faster than previously thought.”

    Farmer’s nitrogen analyses provided a new set of evidence to back up Pico’s research about sea levels during the last ice age.

    “The exciting thing to me is that this provides a completely independent constraint on global sea level during this time period,” Pico said. “Some of the ice sheet histories that have been proposed differ by quite a lot, and we were able to look at what the predicted sea level would be at the Bering Strait and see which ones are consistent with the nitrogen data.”

    “This study brought together experts in the Arctic Ocean, nitrogen cycling and global sea level. And the outcome has consequences not only for climate and sea level but also for human prehistory,” Farmer said. “One of the thrilling aspects of paleoclimate research is the opportunity to collaborate across such a broad range of subjects.”

    “The Bering Strait was flooded 10,000 years before the Last Glacial Maximum,” by Jesse R. Farmer, Tamara Pico, Ona M. Underwood, Rebecca Cleveland Stout, Julie Granger, Thomas M. Cronin, François Fripiat, Alfredo Martínez-García, Gerald H. Haug, and Daniel M. Sigman appears in the current issue of Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.2206742119). The research was supported by the U.S. National Science Foundation (OCE-2054780 and OCE-2054757), the Tuttle and Phillips Funds of the Department of Geosciences, the Max Planck Society, and the USGS Climate Research and Development Program.

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    Princeton University

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