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Comment by Dr. Krishna Kumari Challa on March 27, 2024 at 10:49am

symbolic gesture in birds

Japanese tits (Parus minor) flutter their wings to invite their mate to enter the nest first. Scientists who observed eight breeding pairs of wild tits noticed that when one of the birds sat in front of the next box and fluttered its wings, the other would go in first. It’s the first documented evidence of birds using a symbolic gesture: one that has a specific meaning (like waving ‘goodbye’) but isn’t simply pointing at an object of interest. “It implies that birds have a level of understanding of symbolism that probably a lot of people wouldn’t have given them credit for before.

Comment by Dr. Krishna Kumari Challa on March 27, 2024 at 10:48am

Weird electron behaviour thrills physicists

Two teams have observed that electrons, which usually have a charge of –1, can behave as if they had fractional charges (such as –⅔) — and do so without being nudged by an external magnetic field. It’s the first time this ‘fractional quantum anomalous Hall effect’ has been observed experimentally, and physicists are scratching their heads over exactly how it works. It’s a fundamental discovery that might also someday have practical applications: fractionally charged particles are a key requirement for a certain type of quantum computer. 

Comment by Dr. Krishna Kumari Challa on March 27, 2024 at 9:45am

How can we cool our cities

Light roofs, light roads and better tree cover would make a real difference.

 If your street has established large trees, you will experience less than half the number of days with extreme heat compared on residents on treeless streets. If you live in a leafy street, your home is also worth more.

Blacktop roads are a surprisingly large source of heat. In summer, they can get up to 75°C. Research shows reflective sealants can cut the temperatures up to 13°C. Some councils have experimented with lighter roads, but to date, uptake has been minimal.

Cool roofs markedly reduce how much energy you need to cool a house. When used at scale, they lower the air temperatures of entire suburbs.

The simplest way to get a cool roof is to choose one with as light a color as possible. There are also high-tech options able to reflect even more heat.

Soon, we'll see even higher performance options available in the form of daytime radiative coolers—exceptional cooling materials able to reflect still more heat away from your house and cut glare.

Until we choose to change, homeowners and whole communities will keep paying dearly for the luxury of a dark roof through power bill pain and sweltering suburbs.

https://theconversation.com/if-youve-got-a-dark-roof-youre-spending...

Part 2

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Comment by Dr. Krishna Kumari Challa on March 27, 2024 at 9:43am

If you've got a dark roof, you're spending almost $700 extra a year to keep your house cool

A dark roof means you'll pay considerably more to keep your house cool in summer.When suburbs are full of dark colored roofs, the whole area heats up. And up. And up. This is part of the urban heat island effect.

Light coloured roofs or Cool roofs have many benefits. They slash how much heat gets into your house from the sun, keep the air surrounding your home cooler, boost your aircon efficiency, and make your solar panels work more efficiently.

At present, the world's cities account for 75% of all energy-related carbon dioxide emissions. It's vitally important we understand what makes cities hotter or cooler.

Brick, concrete, tarmac and tiles can store more heat than grass and tree-covered earth can, and release it slowly over time. This keeps the air warmer, even overnight.

Built-up areas also block wind, which cuts cooling. Then there's transport, manufacturing and air-conditioning, all of which increase heat.

The main way people had to keep cool was through how they designed their homes. In hot countries, buildings are often painted white, as well as having small windows and thick stone walls.

Part 1

Comment by Dr. Krishna Kumari Challa on March 27, 2024 at 9:35am

Dust storms may spread bacteria and fungi around the world

When allergy season hits, many blame their reactions on the local flora in the spring. However, African Saharan-Sahelian dust plumes, large enough to register on weather radar, travel around the globe every summer, bringing their own form of air pollution.

Researchers  have furthered previous research to identify microorganisms that might have hitched a ride in the du.... 

We all get allergies and potentially other more severe health effects when we breathe in dust, and it's not fully known as to what causes those allergies. Some people may think it is just the sand or clay minerals in the dust. Others think it is the metals or organics in the dust, and then some think it's the bacteria and fungi.

This research, published in the journal Environmental Science & Technology, is the first to study the association of bacteria and fungi with North American–Saharan dust storms.

Scientists noted that dust events can vary annually, with different elemental compositions each year.

 Microbiota was detected by extracting DNA from filters. Meticulous sequencing techniques detected bacterial genomes from 117 families and fungal genomes from 164 families. The technique did not show whether the microbes were alive, but it did detect several pathogenic bacteria and fungi, many of which are listed in the World Health Organization's global priority list of human pathogens.

It doesn't tell us if they are going to be able to infect us and make us sick. But at least the DNA of several pathogenic bacteria and fungi were identified in the African dust.

The biodiversity of bacteria and fungi was strongly correlated to a few elements, most notably calcium. The study showed that calcium and zirconium are important for explaining bacterial and fungal beta diversity, the ratio between regional and local species diversity.

A similar caveat was found in biota detections. Over 2,000 different organic groups were detected. 

Sourav Das et al, Respirable Metals, Bacteria, and Fungi during a Saharan–Sahelian Dust Event in Houston, Texas, Environmental Science & Technology (2023). DOI: 10.1021/acs.est.3c04158

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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....

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