Comment

Comment by Dr. Krishna Kumari Challa on Tuesday

Confinement may affect how we smell and feel about food

New research  found confined and isolating environments changed the way people smelled and responded emotionally to certain food aromas.

The team in this study compared 44 people's emotional responses and perception of eight food aromas in two environmental scenarios: sitting in reclined chairs that mimic astronauts' posture in microgravity; and then in the confined setting of the International Space Station (ISS), which was simulated for participants with virtual reality goggles.
The aromas the team tested on participants were vanilla, almond, lemon, lemon myrtle, eucalyptus, peppermint, vinegar and lemongrass.

The research, published in Food Research International, builds on previous work by the team and aims to help explain why astronauts report meals taste different in space and struggle to eat their normal nutritional intake over long missions, which has been reported in the news recently.

The study has broader implications for further research to improve the diets of isolated people, including nursing home residents, by personalizing aromas to enhance the flavor of their food.
Part 1

Comment by Dr. Krishna Kumari Challa on Tuesday

The effort resulted in an impressive 775 grassroots submissions, which the researchers then combined with satellite observations and advanced modeling techniques to explore the conditions that had led to the magenta aurora.

The elevation data from these citizen scientists proved to be particularly useful. The researchers used elevation angles to calculate the position of the aurora over time, and found that it was often a surprisingly high altitude of roughly 1,000 km above sea level—which should thus drive a red appearance. But on top of this, the time and season of year meant the atmosphere was more "preheated" ahead of the aurora, in turn driving an upwelling of ionized molecular nitrogen—what is usually responsible for a blue hue.
"Blue plus red makes us see magenta.
And the magenta was made all the more visible and vibrant by the sheer volume of solar activity, even though, ironically, the preheating would also have worked to reduce the peak brightness of the aurora."
Better understanding of magnetic storms goes beyond explaining why humans see the pretty colors of aurorae; these storms can have profound, negative impacts on satellite operations, GPS systems, power grids and even the safety of passengers and crews aboard high-altitude flights.

 Ryuho Kataoka et al, Extended magenta aurora as revealed by citizen science, Scientific Reports (2024). DOI: 10.1038/s41598-024-75184-9

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Comment by Dr. Krishna Kumari Challa on Tuesday

In Japan, space weather researchers took advantage of ordinary people taking pictures of the aurora with their smartphones to organize one of the densest citizen science observation efforts anywhere, despite being a low-latitude country where the aurora was somewhat fainter than in places like Canada or northern Europe.

The different colors of an aurora come from the emission of light from different atoms and molecules in the atmosphere when they are bombarded by the particles from space. The dramatic green hue seen in many photographs of the polar lights comes from atomic oxygen (single atoms of oxygen rather than molecular oxygen, or two oxygen atoms bound together) at the lower altitudes within the atmosphere that are visible to people. (The human eye is also just very sensitive to this color). At even lower altitudes, where atomic oxygen is less common, blue is more visible, and this comes from the greater presence of nitrogen.

At the very highest altitudes in the atmosphere, however, there is a lower concentration of atoms of any kind. The fewer collisions there result in a perception by humans of the excited atomic oxygen atoms as the color red. This is why the upper parts of the aurora curtains can appear as green fading into a scarlet hue.
At low latitudes, as in Japan, normally there is no green at all, only red because only the upper part of the aurora can be seen above the horizon.

"Yet this time, weirdly, the images revealed a very clear and dominant magenta hue to the aurora 'curtains' over Japan, not red.
To solve the mystery, the researchers quickly took to social media to encourage people to observe and report their sightings of the auroras, as well as to input data into a questionnaire asking about observation locations, time, elevation angles and other details, allowing researchers to analyze the auroras' characteristics in unprecedented detail.
Part 2

Comment by Dr. Krishna Kumari Challa on Tuesday

Magenta aurora over Japan

Why May 2024's aurora appeared a magenta color over Japan?

Around the world, the historic geomagnetic superstorm of late spring 2024 inspired millions of non-scientists around the world—many armed with highly sensitive smartphone cameras—to take a fantastic, unprecedented number of images of the aurora it produced.

In Japan, this widespread popular uptake of what is now quite advanced imaging technology (even if it is kept in everyone's pocket) proved to be a tremendous boon for atmospheric physicists and other scientists specializing in "space weather." It allowed them to discover why the Northern Lights over Japan appeared as a mysterious magenta color this time instead of the typical red that is observed when aurorae are visible over that country.

In early May this year, one of the most extreme geomagnetic storms in the history of recording such events hit the Earth's atmosphere. This great "storm" in space, composed of ionized particles, is what produces the aurora borealis, or Northern Lights, in the northern hemisphere and the aurora australis, or Southern Lights, in the southern hemisphere.

This time, however, the storm was so strong—the ninth most severe storm in the 110-year history of Japan's Kakioka Magnetic Observatory, one of the oldest geomagnetic stations in the world—that the polar lights could be photographed at much lower latitudes than normal.
Part 1

Comment by Dr. Krishna Kumari Challa on Tuesday

Widespread wildfires across Canada and droughts in the Amazon in 2023 released about the same amount of carbon to the atmosphere as North America's total fossil fuel emissions, underscoring the severe impact of climate change on natural ecosystems.

The Amazon—one of the world's most crucial carbon sinks—is showing signs of long-term strain, with some regions shifting from absorbing carbon to becoming net sources of carbon emissions.

The researchers suggest that the declining capacity of Earth's land ecosystems to absorb carbon dioxide may indicate that these natural carbon sinks are nearing their limits and no longer able to provide the mitigation service they have historically offered by absorbing half of human-induced carbon dioxide emissions.
Consequently, achieving safe global warming limits will require even more ambitious emission reductions than previously anticipated, the scientists say.
The study also highlights that current climate models might be underestimating the rapid pace and impact of extreme events, such as droughts and fires, on the degradation of these crucial carbon reservoirs.

Piyu Ke et al, Low latency carbon budget analysis reveals a large decline of the land carbon sink in 2023, National Science Review (2024). DOI: 10.1093/nsr/nwae367

Part 2

Comment by Dr. Krishna Kumari Challa on Tuesday

Extreme heat weakens land's power to absorb carbon, analysis finds

A new European Space Agency-backed study shows that the extreme heat waves of 2023, which fueled huge wildfires and severe droughts, also undermined the land's capacity to soak up atmospheric carbon. This diminished carbon uptake drove atmospheric carbon dioxide levels to new highs, intensifying concerns about accelerating climate change.

Measurements from Hawaii's Mauna Loa Observatory showed that atmospheric carbon concentrations surged by 86% in 2023 compared to the previous year, marking a record high since tracking began in 1958.

Despite this sharp increase, fossil fuel emissions only rose by about 0.6%, suggesting that other factors, such as weakened carbon absorption by natural ecosystems, may have driven the spike.

An international team of scientists analyzed global vegetation models and satellite data to investigate the underlying causes and deliver an expedited carbon budget report for 2023.

Typically, land absorbs roughly one-third of human-generated carbon dioxide emissions. However, the team's research published in National Science Review reveals that in 2023, this capacity fell to just one-fifth of its usual level, marking the weakest land carbon sink performance in two decades.

Part 1

Comment by Dr. Krishna Kumari Challa on Tuesday

We are already counting on forests and oceans to mop up our past emissions, most of which came from burning stuff we dug out of the ground. We can't expect them to compensate for future emissions as well. By mid-century, any carbon that still comes out of the ground will have to go back down, to permanent storage. That's Geological Net Zero.
Countries report both emissions and removals, but using all removals in climate targets is a recipe for continued warming. Natural carbon sinks currently clean up around half our annual emissions for free, but this ecosystem service must be kept separate from the fossil emissions driving climate change. Relabeling things will not stop global warming, say the scientists.
They stress that: It is a common assumption that removing carbon from the atmosphere to offset burning of fossil fuels is as effective as not burning fossil fuels in the first place. It is not.
Offsetting continued fossil fuel use with carbon removal will not be effective if the removal is already being counted on as part of the natural carbon cycle and if the carbon is not permanently stored. Unless we can increase transparency in national Greenhouse gas reporting and target setting, offsets will become part of the problem instead of part of the solution.
Land is limited, we rely on it for food, nature, biodiversity, leisure, water storage, and so on. It cannot offset more than a portion of fossil emissions even now, probably less in future, with worsening pressures on the biosphere such as population increase, fires, and drought.

"Giving carbon credits for natural processes that are happening anyway undermines trust in the whole idea of offsetting. We have to urgently protect natural carbon sinks, but there are more scientifically credible and equitable ways of doing this than relying on carbon offset markets."
Is anybody listening?

Myles Allen, Geological Net Zero and the need for disaggregated accounting for carbon sinks, Nature (2024). DOI: 10.1038/s41586-024-08326-8. www.nature.com/articles/s41586-024-08326-8

Part 2

Comment by Dr. Krishna Kumari Challa on Tuesday

Redefining net zero will not stop global warming, scientists say

This is really absurd. Governments and countries are trying to evade climate goals to stop global warming. 

In a study, led by the University of Oxford's Department of Physics and published 18 November in Nature, an international group of authors who developed the science behind net zero demonstrate that relying on 'natural carbon sinks' like forests and oceans to offset ongoing CO2 emissions from fossil fuel use will not actually stop global warming.

The science of net zero, developed over 15 years ago, does not include these natural carbon sinks in the definition of net human-induced CO₂ emissions.

Natural sinks play a vital role in moderating the impact of current emissions and draw down atmospheric CO2 concentrations after the date of net zero, stabilizing global temperatures. Yet governments and corporations are increasingly turning to them to offset emissions, rather than reducing fossil fuel use or developing more permanent CO2 disposal options.

Emissions accounting rules encourage this by creating an apparent equivalence between fossil fuel emissions and drawdown of CO₂ by some natural carbon sinks, meaning a country could appear to have 'achieved net zero' while still contributing to ongoing warming.

The authors call on governments and corporations to clarify how much they are counting on natural carbon sinks to meet their climate goals, as well as recognizing the need for "Geological Net Zero."

Geological Net Zero means balancing flows of carbon into and out of the solid Earth, with one ton of CO₂ committed to geological storage for every ton still generated by any continued fossil fuel use. Given the cost and challenges of permanent geological CO₂ storage, achieving Geological Net Zero will require a substantial reduction in fossil fuel use.

The authors stress the importance of protecting and maintaining natural carbon sinks while accepting that doing so cannot compensate for ongoing fossil fuel use. Total historical CO₂ emissions determine how much a country or company has contributed to the global need for ongoing natural carbon sinks.

Part 1

Comment by Dr. Krishna Kumari Challa on Tuesday

On July 27, medical evaluation revealed light vaginal bleeding and dark discharge, with ultrasonography indicating fetal macrosomia.

By August 5, continued symptoms and decreased fetal movements led to the confirmation of fetal demise.

Molecular diagnostics confirmed acute OROV infection, ruling out dengue, Zika, chikungunya, and Mayaro viruses. Minimal invasive tissue sampling of the stillborn infant revealed OROV RNA in multiple fetal tissues, establishing vertical transmission.

Phylogenetic analysis using maximum-likelihood inference positioned the virus within the OROVBR-2019-2024 lineage, consistent with strains from the ongoing outbreak. These findings link the stillbirth directly to the current OROV spread in Brazil, highlighting the virus's potential risks during pregnancy.

The report should sound the alarm for health care providers to consider OROV infection in pregnant women presenting with fever and related symptoms in endemic or emerging regions.

 Carlos Garcia Filho et al, A Case of Vertical Transmission of Oropouche Virus in Brazil, New England Journal of Medicine (2024). DOI: 10.1056/NEJMc2412812

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Comment by Dr. Krishna Kumari Challa on Tuesday

Oropouche virus transmission to unborn child confirmed

The first confirmed case of vertical transmission of Oropouche virus (OROV) has been reported by 23 researchers from eight distinct institutions in Brazil.

OROV, a zoonotic arbovirus, was first isolated from the blood of a charcoal worker with a high fever in 1955 on the Caribbean island of Trinidad. Outbreaks have typically occurred south of the Amazon, isolated within Amazonian villages.

In 2024, OROV infections were detected in previously non-endemic areas across all five Brazilian regions. These expansions into previously unaffected regions involve new virus variants emerging from genetic reassortment.

In a letter to the editor titled "A Case of Vertical Transmission of Oropouche Virus in Brazil," published October 30, 2024, in the New England Journal of Medicine, researchers report on a case from Ceará, a state historically free from OROV, finding its first infection case through active laboratory surveillance.

Subsequent investigations identified 171 cases, predominantly in the rural valleys of the Baturité Massif. Agricultural landscapes in this region favor the Culicoides paraensis midge, a small biting fly sometimes referred to as "no-see-ums" due to their tiny size. Culicoides is the primary vector for OROV transmission to humans.

A notable case involved a 40-year-old pregnant woman at 30 weeks gestation who developed fever, chills, muscle aches, and severe headache. Routine prenatal care had previously identified gestational diabetes, managed with metformin, and four routine obstetric ultrasounds.

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