Comment

Comment by Dr. Krishna Kumari Challa on March 27, 2024 at 8:50am

The balance of carbon storage versus albedo change that comes from restoring tree cover varies from place to place, but until now we didn't have the tools to tell the good climate solutions from the bad.

This study aims to change that, providing the maps needed to empower smarter decisions while also ensuring that limited finance is directed at those locations where restoring tree cover can make the most positive difference as a natural climate solution.

On the positive, the study also identifies locations within every biome on Earth where the climate mitigation benefits of tree-planting can be achieved. Better still, it also finds that most of the thousands of on-the-ground projects underway globally to restore tree cover are concentrated in these zones of greatest opportunity. Even in these locations, however, albedo changes are likely to offset the net climate benefit by at least 20 percent in around two-thirds of cases.

Researchers have now addressed a significant research gap and gained a much more complete picture of how restoring tree cover can impact our global climate—both positively and also sometimes negatively.

However, it's important to remember that there are many other sound reasons to restore tree cover, even in locations where the climate benefits aren't stellar: clean water, resilient food production, wildlife habitat, the list goes on... Researchers are 're simply calling on governments and land managers to more carefully integrate albedo in their environmental decision-making and are open-sourcing this robust new set of tools to help them do so.

Hasler N., Accounting for albedo change to identify climate positive tree cover restoration., Nature Communications (2024). DOI: 10.1038/s41467-024-46577-1 , www.nature.com/articles/s41467-024-46577-1

To read more about efforts to restore tree cover and to chart the full potential of nature to mitigate climate change, visit naturebase.org to learn more.

Part 2

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Comment by Dr. Krishna Kumari Challa on March 27, 2024 at 8:46am

Albedo can reduce climate benefit of tree planting: New tool identifies locations with high climate-cooling potential

As efforts to restore tree cover accelerate to help avoid runaway climate change, a new study highlights how restoring tree cover can, in some locations, heat up the Earth rather than cool it by affecting how much sunlight the surface reflects (i.e. "the albedo").

This new study by researchers published recently in the journal Nature Communications, provides a global analysis of where restoration of tree cover is most effective at cooling the global climate system, considering not just the cooling from carbon storage but also the warming from decreased albedo.

The researchers provide a tool practitioners and land managers can use to determine just how much of a problem albedo is for any reforestation or afforestation project on the globe. The authors use these new maps to show that previously published 'carbon-only' estimates of the global climate mitigation potential of restoring trees worldwide provided significant overestimation, being anywhere from 20 to 81% too high. Because comprehensive maps of the consequences of albedo change were not previously available, these carbon-only estimates tend to identify too many options in landscapes—particularly semi-arid settings and snowy, boreal regions—where changes in albedo would significantly offset, or even negate, the carbon-removing benefits provided by these trees.

Part 1

Comment by Dr. Krishna Kumari Challa on March 27, 2024 at 6:58am

Tiniest 'starquakes' detected

At a distance of 11.9 light years, Epsilon Indi (ε Indi) is an orange dwarf star (also known as a K dwarf) with 71% of the sun's diameter. An international team, led by Instituto de Astrofísica e Ciências do Espaço (IA) researcher Tiago Campante, studied this star with the ESPRESSO spectrograph, mounted at the European Southern Observatory's (ESO) Very Large Telescope (VLT), and detected the tiniest "starquakes" ever recorded.

The team used a technique dubbed asteroseismology, which measures oscillations in stars. These provide indirect glimpses of stellar interiors, just as earthquakes tell us about Earth's interior. In ε Indi, the peak amplitude of the detected oscillations is just 2.6 centimeters per second (about 14% of the sun's oscillation amplitude), which makes it the smallest and coolest dwarf star observed to date with confirmed solar-like oscillations.

These measurements are so precise that the detected speed is slower than the average speed of a sloth.

The extreme precision level of these observations is an outstanding technological achievement. Importantly, this detection conclusively shows that precise asteroseismology is possible down to cool dwarfs with surface temperatures as low as 4,200 degrees Celsius, about 1,000 degrees cooler than the sun's surface, effectively opening up a new domain in observational astrophysics.

This level of precision might help scientists settle a long-standing disagreement between theory and observations in what concerns the relation between the mass and the diameter of these cool-dwarf stars.

These "starquakes" can now be used to help plan the future European Space Agency's (ESA) PLATO space telescope, a mission in which IA is strongly involved. The oscillation amplitudes measured in this study can be converted to amplitudes in photometry, as they will be measured by PLATO, this being a key piece of information to help accurately predict the seismic yield of PLATO, scheduled to be launched in 2026.

Campante et al, Expanding the frontiers of cool-dwarf asteroseismology with ESPRESSO. Detection of solar-like oscillations in the K5 dwarf ϵ Indi, Astronomy & Astrophysics (2024). DOI: 10.1051/0004-6361/202449197

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:51pm

All of these factors push prices higher and reduce the purchasing power of affected households. The drivers of food inflation are already worsening food insecurity.

The second part of this problem is the rise in inflation itself. A 3% annual price increase would mean households are less able to purchase what they need.

They would likely need to compromise on quality or perhaps even culturally important foods. This in turn makes people more vulnerable to disease and other health issues. Malnutrition is the leading cause of immunodeficiency globally.

Alterations in the climate are a hunger-risk multiplier for those populations with entrenched vulnerability. In light of this, 134 countries at COP28 signed a declaration to incorporate food systems into their climate action, to ensure everyone has enough to eat in light of climate change.

The researchers behind the new study suggest that reducing greenhouse gas emissions could limit any impacts on the global economy. We also suggest that diversifying economies would serve as some protection for those communities reliant on agriculture for both their food and income.

Government intervention could also ensure financial protection and nutritional aid for those vulnerable to becoming trapped in the poverty cycle by inflation and diminished accessibility to food.

https://theconversation.com/food-prices-will-climb-everywhere-as-te...

Part 2

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:50pm

Scientists Warn The Price of Food Is Expected to Increase Every Year From Now on
Climate change, and specifically rising temperatures, may cause food prices to increase by 3.2% per year, according to a new study by researchers in Germany.

As climate change continues to worsen, this price inflation will mean more and more people around the world don't have a varied and healthy diet, or simply don't have enough food.

The new analysis shows that global warming could cause food price inflation to increase by between 0.9 and 3.2 percentage points per year by 2035. The same warming will cause a smaller rise in overall inflation (between 0.3 and 1.2 percentage points), so a greater proportion of household income would need to be spent on buying food.

This effect will be felt worldwide, by high and low-income countries alike, but nowhere more so than in the global south. As with various other consequences of climate change, Africa will be worst affected despite contributing little to its causes.

Shifting seasons, pests and diseases
The first is that the same climate change effects that are causing the inflation are already making food harder to get hold of. For instance, higher temperatures can cause long-established and predictable farming seasons to shift and so may hinder crop production.

Other consequences can include more pest and disease outbreaks that deplete livestock and food reserves, and heat stress to already-poor roads which makes it harder to access rural communities.
Part 1

https://files.springernature.com/getResource/Full%20text%20article....

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:37pm

With this information to hand, the simulations can be put to work to provide real insights into how neutron stars throw their tremendous tantrums.

"We're close to modeling the flame spread across the whole star from pole to pole.

https://iopscience.iop.org/article/10.3847/1538-4357/ace04e

Part 4

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Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:37pm

That sounds simple, but the physics of neutron stars is really complicated; simulating their behavior requires a lot of computing power.

In previous work, the researchers used the Summit supercomputer at Oak Ridge National Laboratory to simulate the thermonuclear flames in two dimensions. Now they've built on that work, and scaled their simulations up to a third dimension.

The model 3D neutron star had a temperature several million times hotter than the Sun, and a spin speed of 1,000 rotations per second, which is pretty close to the theoretical upper limit of neutron star spin speed. Then, they simulated the early evolution of the thermonuclear flame.

Although the flame in the 2D simulation spread slightly faster than the 3D version, the growth trends in both models were very similar. This agreement means that the 2D simulation remains a good tool for studying these hectic explosions, but there are still some things it can't do.

For example, turbulence behaves differently in two and three dimensions; but being able to use the 2D sim for the parts it can do will free up computing power for other things, like increasing the fidelity of the burning

Part 3

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:36pm

Neutron stars are some of the densest objects in the Universe. They're what's left over after a massive star has lived its life, run out of fuel, and exploded in a supernova.

While the outer material blasts off into space, though, the core of the star collapses under gravity, forming a super dense ball around 20 kilometers (12 miles) across, packing as much mass into that tiny sphere as up to 2.3 Suns or so.

Matter that is squished so densely is expected to be a bit wacky, to put it mildly. But scientists can study their thermonuclear bursts to place constraints on their size, which in turn can help model their interiors.

We can't exactly go cozy up to a neutron star to look at them more closely, for a number of reasons (distance, danger, that sort of thing), but we can collect all the information we can about neutron star X-ray bursts, and try to put together a simulation whose results match the observational data.

Part 2

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:35pm

Scientists Ignited a Thermonuclear Explosion Inside a Supercomputer

Computer simulations are giving us new insight into the riotous behavior of cannibal neutron stars.

When a neutron star slurps up material from a close binary companion, the unstable thermonuclear burning of that accumulated material can produce a wild explosion that sends X-radiation bursting across the Universe.

How exactly these powerful eruptions evolve and spread across the surface of a neutron star is something of a mystery. But by trying to replicate the observed X-ray flares using simulations, scientists are learning more about their ins and outs – as well as the ultra-dense neutron stars that produce them.

Part 1

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:33pm

"What makes our recent finding so special is that it shows how individual particles behave in a coupled resonance," Bartosik says. "We can demonstrate that the experimental findings agree with what had been predicted based on theory and simulation."

The next step is to develop a theory that describes how individual particles behave in the presence of an accelerator resonance. This, the researchers say, will ultimately give them a new way to mitigate beam degradation, and achieve the high-fidelity beams required for ongoing and future particle acceleration experiments.

The team's research has been published in Nature Physics.

https://www.nature.com/articles/s41567-023-02338-3

Part 4

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