Other than the same old picture issues, the idea that the agencies have been told to “refocus” on 🇷🇺🇨🇳🇮🇷 neglects the fact that there already has been a growing % on state level threats in recent years – and the agencies are fully aware of the threat.
https://t.co/qc2IqJXk9v— Dr. Dan Lomas (@Sandbagger_01) June 1, 2024
Day: June 1, 2024
Finance Minister Bezalel Smotrich , and National Security Minister Itamar Ben-Gvir condemned the proposed outline for a hostage and ceasefire deal Saturday evening, and threatened to leave the government if PM Benjamin Netanyahu accepted the deal.https://t.co/aSAdx0Pcvh
— The Jerusalem Post (@Jerusalem_Post) June 1, 2024
Integrating big data and a coordinated global field experiment, researchers have developed a model that can predict the decomposition rate of organic matter in rivers worldwide.
The global model estimates decomposition rates in rivers across vast understudied areas of Earth, revealing rapid decomposition across continental-scale areas dominated by human activities. Earth’s terrestrial ecosystems generate over 100 billion tons of plant detritus annually, with its fate – long-term storage, mineralization to greenhouse gasses, or incorporation into food webs – determined by decomposition rates. This organic material is continually added to rivers and streams.
However, the factors that influence organic matter decomposition in rivers are poorly understood, particularly at large spatial scales and in tropical regions, where much of Earth’s plant matter is produced. Accurate global carbon models require a mechanistic understanding of these processes to improve predictions and inform future environmental change scenarios.
To fill these knowledge gaps, Scott Tiegs and colleagues developed a predictive model for cellulose composition using global data from the CELLDEX experiment – a coordinated, distributed experiment on cellulose decomposition in rivers. The CELLDEX experiment investigated the decomposition of standard cotton fabric (as a proxy for plant detritus) in 514 sites across all 7 continents and each of Earth’s major biomes.
These findings were paired with detailed climate, soil, geology, vegetation, and physiochemical data to create a global, high-resolution predictive model of organic-matter decomposition in rivers. According to the authors, the model could accurately explain leaf-litter decomposition estimates from previously published studies. Tiegs et al. found that cellulose decomposition in rivers is significantly influenced by various environmental drivers, which are increasingly affected by human activities globally.
Key human-influenced drivers of cellulose decomposition are temperature and nutrient loading, they say. As a result, ongoing environmental changes are likely to increase decomposition rates, leading to reduced short-term carbon storage in flowing waters and diminished carbon transport to long-term carbon storage sinks, such as reservoirs, floodplains, and oceans.
“To further advance large-scale monitoring and assessment, we have made these modeling approaches accessible through an open-source online mapping tool,” write the authors. “Application of the models to current and future environmental threats will enable scientists and natural-resource managers to forecast changes in the functioning of river networks at a planetary scale.”
Converting home heating systems from natural gas furnaces to electric heat pumps is seen as a way to address climate change by reducing greenhouse gas emissions.
But a new University of Michigan study of 51 Southeast Michigan households shows that switching to efficient, cold-climate heat pumps would increase annual utility bills by an average of about $1,100.
Home weatherization upgrades, such as adding attic insulation and sealing around doors and windows, could help reduce utility bills and make electric heating more affordable.
But those energy retrofits are expensive and are likely beyond the reach of many low-income households, which could lead to what the researchers call an energy poverty trap.
“The clean energy transition is hindered by an energy poverty trap because the extensive retrofits needed to make electrification affordable are themselves too expensive for low-income households,” said study lead author Claire McKenna, a doctoral candidate at the U-M School for Environment and Sustainability.
“Our findings suggest that heat pumps are not a feasible economic alternative for households currently using natural gas, unless governments offset energy cost premiums through public funding. Policymakers should act to help lower the operating costs of heat pumps compared to natural gas for low-income households in cold climates.”
The study was published online May 31 in the peer-reviewed journal Resources, Conservation & Recycling.
Residential heat pumps are reversible air conditioners that use electricity to move heat from one place to another, providing both heating and cooling in a building. In the winter, heat pumps move heat from the outdoors into a building, and in summer they move heat from the inside to the outside.
Heat pumps are growing in popularity and for the last two years have outsold gas furnaces in the United States.
For their study, U-M researchers analyzed utility bills, thermostat settings and energy burdens—the proportion of income that households spend on electricity and gas costs—for 51 homes in Wayne and Washtenaw counties, half of them below median income levels. Then they used a heat pump coefficient-of-performance model to determine energy cost and energy-burden impacts of switching to a heat pump.
The researchers also hired a contractor to conduct energy assessments of the homes and to provide energy-retrofit recommendations, including estimated costs and savings. Members of the research team are from U-M’s School for Environment and Sustainability, the Institute for Social Research and the School of Public Health.
The researchers found that converting homes to electric heat pumps would increase annual energy costs 58%, on average. Below-median-income households, which today experience a median energy burden of 6% (which is considered high and is twice the national average), would see that burden rise to 10% if they switched from natural gas heating to electric heat pumps.
Weatherization could offset the increase, bringing energy burdens back down to pre-electrification levels. However, median payback time for the retrofits was 24 years, making them “infeasible for the poorest,” according to the study authors.
And it’s not just the lowest income households that would feel the pinch of the heat pump transition.
Households earning $50,000 or more annually, which currently have a median energy burden of 2.6%, would see that number rise by more than one percentage point, on average, indicating that “energy burden could become a concern for households which are currently energy secure,” according to the study.
The 51 homes in the study were, on average, 60 years old and were built in an era when Michigan did not have energy-efficient building codes. The cost of the average retrofit package recommended by the energy-audit contractor was $7,628.
On top of that, efficient cold-weather residential heat pumps typically cost between $5,000 and $10,000 for the hardware, and installation costs can double the total price tag.
“The upfront costs of weatherization and heat-pump installation can be very high,” said study senior author Parth Vaishnav of the School for Environment and Sustainability. “Our findings clearly demonstrate the challenges associated with heat pump adoption in cold climates.”
In the study, the lowest-income households had the least energy-efficient homes and also used the lowest amount of energy. That finding suggests that low-income households are likely not using enough energy to meet their health, safety and comfort needs, McKenna said.
Given that households below median income currently have a 6% median energy burden on their existing natural gas heating systems, the transition to electric heat pumps “would severely worsen existing energy insecurity,” the study authors wrote.
“That, in turn, could increase coping behaviors like trading off paying utility bills for paying for rent or food, or the underconsumption of energy in households that struggle to pay their bills. This could have huge ramifications for health,” said study co-author Carina Gronlund, an environmental epidemiologist at the U-M Institute for Social Research and the School of Public Health.
The researchers identified three ways that policymakers can help lower heat pump costs for low-income households in cold climates. First, government-sponsored initiatives to advance more energy-efficient heat-pump technology are essential.
Second, state regulators should exercise “a more robust scrutiny” of utility company returns and create more opportunities to improve customer outcomes in the rate-making process. Most households in the U-M study were DTE customers, with a few supplied by Consumers Energy.
Third, states should consider implementing “percentage of income payment plans,” known as PIPPs, which place a cap on energy expenditures relative to household income. Such programs can be paired with federal- and state-funded retrofit programs to simultaneously improve the building stock and mitigate energy poverty, according to the study authors.
“The economics of electrification are adverse for the existing housing stock in cold climates,” the authors concluded. “Policy action is needed to make heating electrification viable.”
People under age 50 have a greater risk for heart attack or stroke if they’ve lived with obesity for 10 years, according to industry-sponsored research being presented Saturday at ENDO 2024, the Endocrine Society’s annual meeting in Boston, Mass.
“It is well established that people who have excess weight at any point in time have a greater risk of heart attacks and strokes. What was not known was whether it matters for how long someone has been exposed to excess weight,” said Alexander Turchin, M.D., M.S., Director of Quality at the Division of Endocrinology at Brigham & Women’s Hospital and associate professor of medicine at Harvard Medical School in Boston.
Turchin and his team, including researchers from Eli Lilly, conducted a comprehensive study using data from the Nurses’ Health Study (NHS) and Health Professionals Follow-Up Study (HPFS). They specifically focused on patients who had a body-mass index (BMI) greater than 25 kg/m2 at least once over a 10-year period (1990-1999) to understand how their weight impacted their risk for heart attack or stroke over the next two decades (2000-2020).
The researchers analyzed data from 109,259 women and 27,239 men who had an average age of 48.6 years and a BMI of 27.2 kg/m2 in 1990. Of those, 6,862 had atherosclerotic cardiovascular disease, 3,587 had type 2 diabetes, and 65,101 had a history of smoking. At follow-up in 2020, the data revealed 12,048 cardiovascular events.
“We found that among women younger than 50 and men younger than 65, having obesity over a 10-year period was associated with a 25-60% increase in the risk of heart attack and stroke – and was more important than their weight at a single point in time in 1990,” Turchin said.
However, obesity in women older than 50 and men older than 65 was not associated with an increased risk for heart attack and stroke.
These findings are important for clinicians who see younger people living with obesity, as they show that the sooner someone is treated, the better.
“Viewed as a ‘glass half full,’ these findings mean that obesity at any given point in time does not ‘seal’ one’s fate,” Turchin said. “If obesity is treated in a timely fashion, its complications can be prevented.”
One of Earth’s most consequential bursts of biodiversity—a 30-million-year period of explosive evolutionary changes spawning innumerable new species—may have the most modest of creatures to thank for the vital stage in life’s history: worms.
The digging and burrowing of prehistoric worms and other invertebrates along ocean bottoms sparked a chain of events that released oxygen into the ocean and atmosphere and helped kick-start what is known as the Great Ordovician Biodiversification Event, roughly 480 million years ago, according to new findings Johns Hopkins University researchers published in the journal Geochimica et Cosmochimica Acta.
“It’s really incredible to think how such small animals, ones that don’t even exist today, could alter the course of evolutionary history in such a profound way,” said senior author Maya Gomes, an assistant professor in the Department of Earth and Planetary Sciences. “With this work, we’ll be able to examine the chemistry of early oceans and reinterpret parts of the geological record.”
To better understand how changes in oxygen levels influenced large-scale evolutionary events, Gomes and her research team updated models that detail the timing and pace of increasing oxygen over hundreds of millions of years.
They examined the relationship between the mixing of sediment caused, in part, by digging worms with a mineral called pyrite, which plays a key role in oxygen buildup. The more pyrite that forms and becomes buried under the mud, silt, or sand, the more oxygen levels rise.
Researchers measured pyrite from nine sites along a Maryland shoreline of the Chesapeake Bay that serves as a proxy for early ocean conditions. Sites with even just a few centimeters of sediment mixing held substantially more pyrite than those without mixing and those with deep mixing.
The findings challenge previous assumptions that the relationship between pyrite and sediment mixing remained the same across habitats and through time, Gomes said.
Conventional wisdom held that as animals churned up sediments by burrowing in the ocean floor, newly unearthed pyrite would have been exposed to and destroyed by oxygen in the water, a process that would ultimately prevent oxygen from accumulating in the atmosphere and ocean. Mixed sediments have been viewed as evidence that oxygen levels were holding steady.
The new data suggests that a small amount of sediment mixing in water with very low levels of oxygen would have exposed buried pyrite, sulfur, and organic carbon to just enough oxygen to kick-start the formation of more pyrite.
“It’s kind of like Goldilocks. The conditions have to be just right. You have to have a little bit of mixing to bring the oxygen into the sediment, but not so much that the oxygen destroys all the pyrite and there’s no net buildup,” said Kalev Hantsoo, a doctoral candidate at Johns Hopkins and first author on the article.
When the researchers applied this new relationship between pyrite and the depth of sediment mixing to existing models, they found oxygen levels stayed relatively flat for millions of years and then rose during the Paleozoic era, with a steep rise occurring during the Ordovician period.
The extra oxygen likely contributed to the Great Ordovician Biodiversification Event, when new species rapidly flourished, the researchers said.
“There’s always been this question of how oxygen levels relate to the moments in history where evolutionary forces are ramped up and you see a greater diversity of life on the planet,” Gomes said. “The Cambrian period also had a massive speciation event, but the new models allow us to rule out oxygen and focus on other things that may have driven evolution during that time.”
A great armada entered the North Atlantic, launched from the cold shores of North America. But rather than ships off to war, this force was a fleet of icebergs. And the havoc it wrought was to the ocean current itself.
This scene describes a Heinrich Event, or a period of rapid iceberg discharge from the Laurentide Ice Sheet during the last glacial maximum. These episodes greatly weakened the system of ocean currents that circulates water within the Atlantic Ocean. The Atlantic Meridional Overturning Circulation, or AMOC for short, brings warm surface water north and cold deep water south. This oceanic conveyor belt is a major component of the global climate system, influencing marine ecosystems, weather patterns and temperatures.
It’s also regarded as a potential tipping element of the Earth’s climate, meaning that a tiny perturbation could push the system to a point of no return. “That’s why a lot of people are worried about a potential collapse of the AMOC,” said Yuxin Zhou, a postdoctoral researcher in UC Santa Barbara’s Department of Earth Science. A weakened AMOC would have a global impact, dropping temperatures in the northern hemisphere and raising them in the south. We’d see dramatic cooling in western Europe and eastern North America, and changes in the tropical rain belt that impact the Amazon and central Africa.
Zhou compared the rate of icebergs coming from the Greenland Ice Sheet to ice flux during Heinrich Events, the last time the AMOC collapsed. He found that as Greenland’s ice sheet retreats inland, its iceberg calving likely will not persist long enough to completely derail the Atlantic circulation. That said, increased freshwater runoff and continued global warming remain threats to the circulation’s stability. The results appear in the journal Science.
“I think that sometimes people are in such despair about the future of the climate that they just give up,” Zhou said. “This study is saying that there is still hope, and we should act with that in mind.”
The North Atlantic is the lynchpin of the AMOC. This is where surface water chills and sinks to the deep ocean, driving this marine conveyor belt, which is a component of the global current system. Adding cold freshwater to the North Atlantic can disrupt this process, a frightening prospect for human society.
Scientists have a number of ways to predict how the AMOC will evolve in the future, including modern observations, statistical analyses and computational models. But the ocean is vast and complex, making it difficult to capture many of its nuances in studies.
Zhou went back in history to study the most recent period when the AMOC was severely weakened — from 68,000 to 16,000 years ago, during the last glacial period. During cooler periods there is more water locked up in ice sheets, creating a reservoir for quickly flushing the ocean with freshwater in the form of icebergs or runoff. Scientists call these episodes Heinrich Events when they came from the Laurentide Ice Sheet. “Today it does not exist. But it used to cover northern North America and was kilometers thick in New York City,” Zhou said.
Comparing these Heinrich Events to current melting in Greenland enabled Zhou to predict how current trends might change the AMOC in the future. Icebergs bring larger sediment out to sea than water or wind, a signature that geologist Hartmut Heinrich noticed in seafloor cores in the North Atlantic. To estimate how much ice each Heinrich Event released, Yuxin analyzed the amount of thorium-230 found in these sediments. This radioactive element is formed from the decay of naturally occurring uranium in seawater. Unlike uranium, thorium doesn’t dissolve well in water, so it precipitates out on particles in the water column. Because thorium-230 is produced at a steady rate, more sediment flux dilutes its concentration. Working in reverse: Less thorium means more sediment raining down, carried by more icebergs.
While this technique has been used before, Zhou is the first to compare the melting rate of icebergs during Heinrich Events to current trends and projections for Greenland’s ice sheet. Zhou discovered that Greenland’s predicted ice outflow is on par with a mid-range Heinrich Event. And what are the effects of a mid-range Heinrich Event?
“Dramatic,” Zhou replied. “It can be bad.”
“This is surprising, and people should be worried. But — and this is a big ‘but’ — during Heinrich Events, the AMOC was already moderately weakened before all the icebergs came in,” he said. “In contrast, the circulation is very vigorous right now.” This difference in initial state is cause for some relief.
Heinrich Events also lasted for tens to hundreds of years. In contrast, the industrial revolution only began around the late 18th century, with carbon emissions ramping up much later. “It is possible that we simply haven’t screwed up badly enough for long enough for it to really mess up the AMOC,” Zhou remarked.
There’s another nuance to the story. Not all melting has the same effect on the Atlantic circulation. Freshwater released as icebergs has a much larger impact on the AMOC than runoff, which is released after melting on land. Icebergs can cool the surrounding seawater, causing it to freeze into sea ice. Ironically, this ice layer acts as a blanket, keeping the ocean surface warm and preventing it from plunging down to the depths and driving the Atlantic circulation. What’s more, icebergs travel much farther out to sea than runoff, delivering freshwater to the regions where this deepwater formation occurs.
Scientists on the Intergovernmental Panel on Climate Change predict that the AMOC will weaken moderately over the 21st century, a trend similar to the effects of a Heinrich Event. However, Greenland’s ice discharge is projected to dwindle by that time as its ice sheet melts. This will cause its glaciers to recede inland, meaning they melt on land and release freshwater runoff rather than icebergs.
“This presents a tug-o-war between these two factors: the more disruptive but decreasing ice discharge and the less effective but accelerating runoff,” Zhou explained. “It’s going to be a competition, and the interplay between the two will determine the future of the AMOC.”
Zhou hopes to study the factors that caused Heinrich Events in the future. Some research suggests that each episode was preceded by ice discharge in the Pacific Ocean from the smaller Cordilleran Ice Sheet. Although this ice sheet hasn’t left any remnants, Zhou believes studying these Siku Events, as the latter are known, could provide more insight on global ocean circulation.
He’s also interested in the sediments around Antarctica. While Greenland’s location causes it to dominate the AMOC, the southern ice sheet is much larger, meaning it could have a greater influence on global sea level and salinity. Further, the West Antarctic Ice Sheet is marine based, making it more susceptible to a feedback loop that could induce runaway melting. Zhou believes that applying the methodologies in this study to the Antarctic ice sheets could provide a better understanding of their future evolution and impacts.
“We have a lot of anxiety about how fast climate change is happening and how dramatic the changes could be,” Zhou said. “But this is a piece of good climate news that hopefully will dissuade people from climate doomism, and give people hope, because we do need hope to fight the climate crisis.”
