"Today, the climate driver isn't weak volcanic or solar changes -- it's human activity, and we are now massively forcing the system," observes Dr Paul Halloran, of the University of Exeter
Arctic sea ice cannot "quickly bounce back" if climate change causes it to melt, new research suggests.
A team of scientists led by the University of Exeter used the shells of quahog clams, which can live for hundreds of years, and climate models to discover how Arctic sea ice has changed over the last 1,000 years.
They found sea ice coverage shifts over timescales of decades to centuries -- so shrinking ice cannot be expected to return rapidly if climate change is slowed or reversed. [...]
At least a third of past variation was found to be "forced" -- showing the climate system is "very sensitive" to such driving factors, according to lead author Dr Paul Halloran, of the University of Exeter.
"There is increasing evidence that many aspects of our changing climate aren't caused by natural variation, but are instead 'forced' by certain events," he said.
Could an intentional massive force save us?
The top climate change scientist for NOAA said he has received $4 million from Congress and permission from his agency to study two emergency—and controversial—methods to cool the Earth if the U.S. and other nations fail to reduce global greenhouse gas emissions. [...]
Fahey said he has received backing to explore two approaches.
One is to inject sulfur dioxide or a similar aerosol into the stratosphere to help shade the Earth from more intense sunlight. It is patterned after a natural solution: volcanic eruptions, which have been found to cool the Earth by emitting huge clouds of sulfur dioxide.
The second approach would use an aerosol of sea salt particles to improve the ability of low-lying clouds over the ocean to act as shade.
This technique is borrowed from “ship tracks”—or long clouds left by the passage of ocean freighters that are seen by satellites as reflective pathways. They could be widened by injections of vapor from seawater by specialized ships to create shading effects.
ICYMI — IT WASN’T SNAKES
In Germany with cavity-nesting bees (bold added)
In a paired study design, we assessed cavity-nesting bees in 15 pairs of organically and conventionally managed vineyards along a gradient of landscape complexity. We found that organic management, even though it enhanced flower availability in the vineyards, was only partially beneficial for cavity-nesting bee abundance. Abundance and species richness were enhanced by either semi-natural habitat area or proximity of woody elements like hedges or forest remnants, most likely due to the nesting demands of this particular group of pollinators. We conclude that vineyards can help to sustain cavity-nesting bee abundance, given that landscapes are managed accordingly. We recommend maintaining or establishing woody elements between vineyards, which is likely to also benefit additional groups of organisms such as breeding birds in viticultural landscapes.
science mag —
It may not sound like much, but the audio clip below is the first reconstruction of an ancient human voice—one belonging to a 3000-year-old Egyptian mummy named Nesyamun.
To recover this echo from the past, scientists placed the mummy in a computerized tomography scanner (pictured). This allowed them to create a 3D model of his vocal tract, the dimensions of which shape the unique sound of a person’s voice.
The researchers then synthesized Nesyamun’s voice by 3D printing a model of his airway and connecting it to an electronic larynx, an artificial voice box that provides a noise source. The resulting utterance is brief, but it gives a sense of what this ancient Egyptian may have sounded like, the team concludes today in Scientific Reports.
Reported as This is The Truth, the study looked at samples from 23 lakes in southern New England. So a more accurate title would be Native Americans barely had any impact on the Southern New England Landscape ….
"The ecological impact of Native Americans before European arrival has been debated for decades," he told Newsweek. "The generally accepted view, which became established in the 1980s with the publication of the book Changes in the Land, is that Native Americans cleared forests and used fire to open the landscape for agriculture and improve habitat for the plants and animals they relied upon.
"This understanding of the past has provided the rationale for using prescribed fire to manage open habitats on many conservation lands across southern New England."
The paper, published in the journal Nature Sustainability, has called into question the scale of this environmental impact.
"The paleo-climate, paleo-ecology and archaeological records suggest that native peoples were not modifying their immediate environments to a great degree," Elizabeth Chilton, one of the authors of the study from Binghamton University, said in a statement. "And they certainly were not doing so with large-scale fire or clear-cutting of trees.
"The widespread and intensive deforestation and agriculture brought by Europeans in the 17th century was in clear contrast to what had come before."
Stress causes grey hair. Just like your mama said it would.
Empirical and anecdotal evidence has associated stress with accelerated hair greying (formation of unpigmented hairs)1,2, but so far there has been little scientific validation of this link. Here we report that, in mice, acute stress leads to hair greying through the fast depletion of melanocyte stem cells.
A ketogenic diet—which provides 99 percent of calories from fat and protein and only 1 percent from carbohydrates—produces health benefits in the short term, but negative effects after about a week, Yale researchers found in a study of mice. [...]
In the Yale study, published in the Jan. 20 issue of Nature Metabolism, researchers found that the positive and negative effects of the diet both relate to immune cells called gamma delta T-cells, tissue-protective cells that lower diabetes risk and inflammation. [...]
When the body's glucose level is reduced due to the diet's low carbohydrate content, the body acts as if it is in a starvation state—although it is not—and begins burning fats instead of carbohydrates. This process in turn yields chemicals called ketone bodies as an alternative source of fuel. When the body burns ketone bodies, tissue-protective gamma delta T-cells expand throughout the body.
This reduces diabetes risk and inflammation, and improves the body's metabolism ... After a week on the keto diet, he said, mice show a reduction in blood sugar levels and inflammation.
But when the body is in this "starving-not-starving" mode, fat storage is also happening simultaneously with fat breakdown, the researchers found. When mice continue to eat the high-fat, low-carb diet beyond one week, Dixit said, they consume more fat than they can burn, and develop diabetes and obesity.
A new study of ice cores in glaciers in the autonomous Chinese region of Tibet reveals that the ice floes are holding viruses previously unencountered by humans, raising the possibility of the microbes being released as the climate crisis continues.
"We've opened up a Pandora's box with climate change," observed one Twitter user.
The report, "Glacier ice archives fifteen-thousand-year-old viruses," was published in the journal bioRxiv in early January by the scientists who examined the cores. It is awaiting peer review.
According to NBC News:
The experiment revealed 33 groups of virus genuses (also known as genera) in the ice cores. Of these, 28 were previously unknown to science, the researchers said. "The microbes differed significantly across the two ice cores," the researchers wrote in the study, "presumably representing the very different climate conditions at the time of deposition."
The researchers warn that, "in a worst case scenario," these and possibly other pathogens could be released as the climate crisis melts glaciers around the world.
Atoms are known for forming bonds and breaking apart, a process that’s crucial to basically everything in the universe. But because it happens on such a tiny scale, it’s difficult to study and record. Now, researchers from the Universities of Nottingham and Ulm have managed to capture atoms forming and breaking bonds on video for the first time.
The team used transmission electron microscopy (TEM) to image a pair of rhenium atoms, as they “walked” hand in hand along a carbon nanotube. With a quadruple bond between them, the two atoms form a molecule of Re2.
Footage of atoms bonding, using advanced microscopy methods scientists captured a moment of breaking a chemical bond, around half a million times smaller than the width of a human hair.Credit: University of Nottingham
science daily —
... A new study shows that infested tomato plants, in their efforts to fight off caterpillars, don't adapt well to rising temperatures. This double-edged sword worsens their productivity.
According to the study, two factors are at play. The first is rising temperatures. Insect metabolism speeds up with heat and they eat more. Also, warmer temperatures could open up a wider range of hospitable habitats to insects.
Second, and this is what current models ignore, is how the infested plants react to the heat.
"We know that there are constraints that prevent plants from dealing with two stresses simultaneously," said Gregg Howe, University Distinguished Professor at the MSU-DOE Plant Research Laboratory. "In this case, little is known about how plants cope with increased temperature and insect attack at the same time, so we wanted to try and fill that gap."
A new study uses machine learning to project migration patterns resulting from sea-level rise. Researchers found the impact of rising oceans will ripple across the country, beyond coastal areas at risk of flooding, as affected people move inland. Popular relocation choices will include land-locked cities such as Atlanta, Houston, Dallas, Denver and Las Vegas. The model also predicts suburban and rural areas in the Midwest will experience disproportionately large influx of people relative to their smaller local populations.
Despite reports that global emissions of the potent greenhouse gas, , were almost eliminated in 2017, an international team of scientists, led by the University of Bristol, has found atmospheric levels growing at record values.
Over the last two decades, scientists have been keeping a close eye on the atmospheric concentration of a hydrofluorocarbon (HFC) gas, known as HFC-23.
This gas has very few industrial applications. However, levels have been soaring because it is vented to the atmosphere during the production of another chemical widely used in cooling systems in developing countries.
Scientists are concerned, because HFC-23 is a very potent greenhouse gas, with one tonne of its emissions being equivalent to the release of more than 12,000 tonnes of carbon dioxide.
The western United States has experienced such intense droughts over the past decade that technical descriptions are becoming inadequate. In many places, conditions are rocketing past "severe," through "extreme," all the way to "exceptional drought."
The 2018 Four Corners drought -- centered on the junction between Arizona, Utah, Colorado and New Mexico -- put the region deep in the red. An abnormally hot spring and summer indicated that climate change was clearly at work, but that was about as much as most people could say of the situation at the time.
Climate scientists from UC Santa Barbara's geography department have now distilled just how strong an effect human-induced warming had on that event. Their findings appear in the Bulletin of the American Meteorological Society's annual issue dedicated to explaining extreme weather events during the previous year. The team found that 60 to 80% of the region's increased potential for evaporation stemmed from human-induced warming alone, which caused additional warming of 2 degrees Celsius.
"I was really stunned at how big an effect we found with just a 2-degree warming," said Chris Funk, director of the university's Climate Hazards Center, a U.S. Geological Survey scientist and one of the study's coauthors.
phys.org —
When it comes to restoring rangeland habitats, there is no replacement for "prescribed fire," according to Agricultural Research Service (ARS) ecologists.
Using fire with a stated objective—a strategy known as prescribed fire—is widely recognized as an effective way to remove standing, dead vegetation on rangelands. But fear of fire has left some to wonder if mowing or close grazing confers the same benefits.
Lance Vermeire, an ecologist at the ARS Fort Keogh Livestock and Range Research Laboratory in Miles City, Montana, compared the benefits of mowing rangelands with setting them on fire to rid them of unwanted debris and reset their ecological balance. He found in a recent study that fire is better than mowing because it restores soil health and promotes growth of grass that is more nutritious for grazing cattle.
"The results show that mowing is not the same as fire and cannot replace it. Fire is unique," he says.
Organoids have become an important tool for studying many disease processes and testing potential drugs. Now, they are being used in a surprising and unexpected way: for the production of snake venom. On January 23 in the journal Cell, researchers are reporting that they have created organoids of the venom glands of the Cape coral snake (Aspidelaps lubricus cowlesi) and that these glands are capable of producing venom.
"More than 100,000 people die from snake bites every year, mostly in developing countries. Yet the methods for manufacturing antivenom haven't changed since the 19th century," says senior author Hans Clevers of the Hubrecht Institute for Developmental Biology and Stem Cell Research at Utrecht University in the Netherlands. "It's clear there is a huge unmet medical need for new treatments."
He adds: "Every snake has dozens of different components in their venom. These are extremely potent molecules that are designed to stop prey from running away. They affect systems as varied as the brain, neuromuscular junctions, blood coagulation, and more. Many of them have potential bioprospecting applications for new drugs."
These findings suggest that animals have the capacity to adapt their behaviors to survive extreme weather events. Since global climate change has the potential to contribute to an increase in flooding, drought, hurricanes, and tsunamis, this research has broad implications for wildlife behavioral mitigation strategies.
"In a lot of our climate change assessments, we make the assumption that animal behavior is static and that what we observe now is how the animals are going to respond in extreme events, such as hurricanes," Abernathy explained. "What this research demonstrates is that animals have behavioral mechanisms that allow for survival, but those mechanisms aren't going to be observed until the animals are undergoing a significant event."
Abernathy's research has local implications as well: because deer seek higher elevations of pine forests during heavy storms, it is essential that land managers and conservationists protect and manage these environments. They could mean the difference between life and death for this key prey species of the endangered Florida panther.
In the wake of a devastating wildfire, burnt land has a respite before the next blaze. But until now, no one has known just how long that effect lasted across the US West. Researchers from the University of Colorado Denver and Portland State looked into the increasing rates and intensity of fires in the U.S. West, like Colorado's Hayman Fire and California's Camp Fire, are up tenfold over the last 40 years. They wanted to know, once the shrubs, trees and other woody fuels have burned up, how long before the next one?
"We generally get about 10 to 15 years of 'protection' post burn, meaning a lower probability of reburning—not a long time," … the reburn effect is shorter in California and longer in the Rockies.
Reburning is incredibly impactful ecologically and can rapidly eliminate forests for the long term, as forest systems aren't generally resilient to high rates of high intensity fire. Logically, it seems like the increase in fires would eventually self-regulate; that an increase in fire rates could limit future fire occurrence—called a "negative feedback." Buma and his team found that this negative feedback and downtime between fires depended on climate, drought conditions, and the ecosystem type/fuel (read: trees, shrubs, grass).
While conducting fieldwork in Puerto Rico's central mountainous region in 2016, University of Michigan ecologists noticed tiny trails of bright orange snail excrement on the undersurface of coffee leaves afflicted with coffee leaf rust, the crop's most economically important pest.
Intrigued, they conducted field observations and laboratory experiments over the next several years and showed that the widespread invasive snail Bradybaena similaris, commonly known as the Asian tramp snail and normally a plant-eater, had shifted its diet to consume the
fungal pathogen that causes coffee leaf rust, which has ravaged coffee plantations across Latin America in recent years.
Now the U-M researchers are exploring the possibility that B. similaris and other snails and slugs, which are part of a large class of animals called gastropods, could be used as a
biological control to help rein in coffee leaf rust. But as ecologists, they are keenly aware of the many disastrous attempts at biological control of pests in the past.