Tag: The Conversation

Hollywood movie to reality?

Where is the global climate going?

The challenge with writing posts, albeit not so often, about the global environment, especially when I am a non-scientist, is that one relies entirely on the words of others. In the case of a recent article, published by The Conversation, the authors are claimed to be specialists, and I do not doubt their credentials.

The three authors are René van Westen who is a Postdoctoral Researcher in Climate Physics, at Utrecht University, Henk A. Dijkstra who is a Professor of Physics, also at Utrecht University, and Michael Kliphuis, a Climate Model Specialist, again at Utrecht University.

So, here is their article:

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Atlantic Ocean is headed for a tipping point − once melting glaciers shut down the Gulf Stream, we would see extreme climate change within decades, study shows

Too much fresh water from Greenland’s ice sheet can slow the Atlantic Ocean’s circulation. Paul Souders/Stone via Getty Images

René van Westen, Utrecht University; Henk A. Dijkstra, Utrecht University, and Michael Kliphuis, Utrecht University

Superstorms, abrupt climate shifts and New York City frozen in ice. That’s how the blockbuster Hollywood movie “The Day After Tomorrow” depicted an abrupt shutdown of the Atlantic Ocean’s circulation and the catastrophic consequences.

While Hollywood’s vision was over the top, the 2004 movie raised a serious question: If global warming shuts down the Atlantic Meridional Overturning Circulation, which is crucial for carrying heat from the tropics to the northern latitudes, how abrupt and severe would the climate changes be?

Twenty years after the movie’s release, we know a lot more about the Atlantic Ocean’s circulation. Instruments deployed in the ocean starting in 2004 show that the Atlantic Ocean circulation has observably slowed over the past two decades, possibly to its weakest state in almost a millennium. Studies also suggest that the circulation has reached a dangerous tipping point in the past that sent it into a precipitous, unstoppable decline, and that it could hit that tipping point again as the planet warms and glaciers and ice sheets melt.

In a new study using the latest generation of Earth’s climate models, we simulated the flow of fresh water until the ocean circulation reached that tipping point.

The results showed that the circulation could fully shut down within a century of hitting the tipping point, and that it’s headed in that direction. If that happened, average temperatures would drop by several degrees in North America, parts of Asia and Europe, and people would see severe and cascading consequences around the world.

We also discovered a physics-based early warning signal that can alert the world when the Atlantic Ocean circulation is nearing its tipping point.

The ocean’s conveyor belt

Ocean currents are driven by winds, tides and water density differences.

In the Atlantic Ocean circulation, the relatively warm and salty surface water near the equator flows toward Greenland. During its journey it crosses the Caribbean Sea, loops up into the Gulf of Mexico, and then flows along the U.S. East Coast before crossing the Atlantic.

Two illustrations show how the AMOC looks today and its weaker state in the future
How the Atlantic Ocean circulation changes as it slows. IPCC 6th Assessment Report

This current, also known as the Gulf Stream, brings heat to Europe. As it flows northward and cools, the water mass becomes heavier. By the time it reaches Greenland, it starts to sink and flow southward. The sinking of water near Greenland pulls water from elsewhere in the Atlantic Ocean and the cycle repeats, like a conveyor belt.

Too much fresh water from melting glaciers and the Greenland ice sheet can dilute the saltiness of the water, preventing it from sinking, and weaken this ocean conveyor belt. A weaker conveyor belt transports less heat northward and also enables less heavy water to reach Greenland, which further weakens the conveyor belt’s strength. Once it reaches the tipping point, it shuts down quickly.

What happens to the climate at the tipping point?

The existence of a tipping point was first noticed in an overly simplified model of the Atlantic Ocean circulation in the early 1960s. Today’s more detailed climate models indicate a continued slowing of the conveyor belt’s strength under climate change. However, an abrupt shutdown of the Atlantic Ocean circulation appeared to be absent in these climate models. https://www.youtube.com/embed/p4pWafuvdrY?wmode=transparent&start=0 How the ocean conveyor belt works.

This is where our study comes in. We performed an experiment with a detailed climate model to find the tipping point for an abrupt shutdown by slowly increasing the input of fresh water.

We found that once it reaches the tipping point, the conveyor belt shuts down within 100 years. The heat transport toward the north is strongly reduced, leading to abrupt climate shifts.

The result: Dangerous cold in the North

Regions that are influenced by the Gulf Stream receive substantially less heat when the circulation stops. This cools the North American and European continents by a few degrees.

The European climate is much more influenced by the Gulf Stream than other regions. In our experiment, that meant parts of the continent changed at more than 5 degrees Fahrenheit (3 degrees Celsius) per decade – far faster than today’s global warming of about 0.36 F (0.2 C) per decade. We found that parts of Norway would experience temperature drops of more than 36 F (20 C). On the other hand, regions in the Southern Hemisphere would warm by a few degrees.

Two maps show US and Europe both cooling by several degrees if the AMOC stops.
The annual mean temperature changes after the conveyor belt stops reflect an extreme temperature drop in northern Europe in particular. René M. van Westen

These temperature changes develop over about 100 years. That might seem like a long time, but on typical climate time scales, it is abrupt.

The conveyor belt shutting down would also affect sea level and precipitation patterns, which can push other ecosystems closer to their tipping points. For example, the Amazon rainforest is vulnerable to declining precipitation. If its forest ecosystem turned to grassland, the transition would release carbon to the atmosphere and result in the loss of a valuable carbon sink, further accelerating climate change.

The Atlantic circulation has slowed significantly in the distant past. During glacial periods when ice sheets that covered large parts of the planet were melting, the influx of fresh water slowed the Atlantic circulation, triggering huge climate fluctuations.

So, when will we see this tipping point?

The big question – when will the Atlantic circulation reach a tipping point – remains unanswered. Observations don’t go back far enough to provide a clear result. While a recent study suggested that the conveyor belt is rapidly approaching its tipping point, possibly within a few years, these statistical analyses made several assumptions that give rise to uncertainty.

Instead, we were able to develop a physics-based and observable early warning signal involving the salinity transport at the southern boundary of the Atlantic Ocean. Once a threshold is reached, the tipping point is likely to follow in one to four decades.

A line chart of circulation strength shows a quick drop-off after the amount of freshwater in the ocean hits a tipping point.
A climate model experiment shows how quickly the AMOC slows once it reaches a tipping point with a threshold of fresh water entering the ocean. How soon that will happen remains an open question. René M. van Westen

The climate impacts from our study underline the severity of such an abrupt conveyor belt collapse. The temperature, sea level and precipitation changes will severely affect society, and the climate shifts are unstoppable on human time scales.

It might seem counterintuitive to worry about extreme cold as the planet warms, but if the main Atlantic Ocean circulation shuts down from too much meltwater pouring in, that’s the risk ahead.

This article was updated to Feb. 11, 2024, to fix a typo: The experiment found temperatures in parts of Europe changed by more than 5 F per decade.

René van Westen, Postdoctoral Researcher in Climate Physics, Utrecht University; Henk A. Dijkstra, Professor of Physics, Utrecht University, and Michael Kliphuis, Climate Model Specialist, Utrecht University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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I am 79! I like to think that whatever is coming down the wires, so to speak, will be after my death. But that is a cop out for a) I have a son and a daughter who are in their early fifties, b) I have a grandson, my daughter and son-in-law’s young man, who is a teenager, with his birthday next month, and c) I could possibly live for another twenty years.

The challenge is how to bring this imminent catastrophic global change in temperature to the fore. We need a global solution now enforced by a globally respected group of scientists and leaders, and, frankly, I do not see that happening.

All one can do is to hope. Hope that the global community will eschew the present-day extremes of warring behaviour and see the need for change. That is NOW!

So that the Hollywood movie, The Day After Tomorrow, remains a fictional story. And for those that have forgotten the film or who have never seen it, here is a small slice of a Wikipedia report:

The Day After Tomorrow is a 2004 American science fiction disaster film conceived, co-written, directed, co-produced by Roland Emmerich, based on the 1999 book The Coming Global Superstorm by Art Bell and Whitley Strieber, and starring Dennis Quaid, Jake Gyllenhaal, Sela Ward, Emmy Rossum, and Ian Holm. The film depicts catastrophic climatic effects following the disruption of the North Atlantic Ocean circulation, in which a series of extreme weather events usher in climate change and lead to a new ice age.

Wikipedia

And here is a YouTube video:

There we go, folks!

Atmospheric river hitting us in Merlin

The atmospheric river in California is reaching up to Southern Oregon

After we had the thick end of twelve inches of rain in January, February has kept up the downpours; as of yesterday morning we had had 0.52 inches (1.32 cm) for the month and it was still raining. (And 0.8 in at 08:00 this morning.)

Here’s an item from yesterday about the situation in California.

Plus the BBC News had an item on the California flood.

So it seemed opportune to present this article on atmospheric rivers.

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What is an atmospheric river? A hydrologist explains the good and bad of these flood-prone storms and how they’re changing

A satellite image shows a powerful atmospheric river hitting the Pacific Northwest in December 2023. Darker greens are more water vapor. Lauren Dauphin/NASA Earth Observatory

By Qian Cao, University of California, San Diego

A series of atmospheric rivers is bringing the threat of heavy downpours, flooding, mudslides and avalanches to the Pacific Northwest and California this week. While these storms are dreaded for the damage they can cause, they are also essential to the region’s water supply, particularly in California, as Qian Cao, a hydrologist at the University of California, San Diego, explains.

What are atmospheric rivers?

An atmospheric river is a narrow corridor or filament of concentrated water vapor transported in the atmosphere. It’s like a river in the sky that can be 1,000 miles long. On average, atmospheric rivers have about twice the regular flow of the Amazon River.

When atmospheric rivers run up against mountains or run into local atmospheric dynamics and are forced to ascend, the moisture they carry cools and condenses, so they can produce intense rainfall or snowfall. https://www.youtube.com/embed/w3rtYM0HtIM?wmode=transparent&start=0 A satellite view of atmospheric rivers.

Atmospheric rivers occur all over the world, most commonly in the mid-latitudes. They form when large-scale weather patterns align to create narrow channels, or filaments, of intense moisture transport. These start over warm water, typically tropical oceans, and are guided toward the coast by low-level jet streams ahead of cold fronts of extratropical cyclones.

Along the U.S. West Coast, the Pacific Ocean serves as the reservoir of moisture for the storm, and the mountain ranges act as barriers, which is why the western sides of the coastal ranges and Sierra Nevada see so much rain and snow.

Why are back-to-back atmospheric rivers a high flood risk?

Consecutive atmospheric rivers, known as AR families, can cause significant flooding.

The first heavy downpours saturate the ground. As consecutive storms arrive, their precipitation falls on soil that can’t absorb more water. That contributes to more runoff. Rivers and streams fill up. In the meantime, there may be snowmelt due to warm temperatures, further adding to the runoff and flood risk.

California experienced a historic run of nine consecutive atmospheric rivers in the span of three weeks in December 2022 and January 2023. The storms helped bring most reservoirs back to historical averages in 2023 after several drought years, but they also produced damaging floods and debris flows.

An animation shows filaments of water heading toward the coast.
Atmospheric rivers forming over the tropical Pacific Ocean head for the U.S. West Coast. NOAA

The cause of AR families is an active area of research. Compared with single atmospheric river events, AR families tend to be associated with lower atmospheric pressure heights across the North Pacific, higher pressure heights over the subtropics, a stronger and more zonally elongated jet stream and warmer tropical air temperatures.

Large-scale weather patterns and climate phenomena such as the Madden-Julian Oscillation, or MJO, also play an important role in the generation of AR families. An active MJO shift occurred during the early 2023 events, tilting the odds toward increased atmospheric river activity over California.

A truck drives through muddy streets that fill a large section of town. People stand on one small patch of pavement not flooded.
An aerial view shows a flooded neighborhood in the community of Pajaro in central California on March 11, 2023, after a series of atmospheric rivers. Josh Edelson/AFP via Getty Images

A recent study by scientists at Stanford and the University of Florida found that storms within AR families cause three to four times more economic damage when the storms arrive back to back than they would have caused by themselves.

How important are atmospheric rivers to the West Coast’s water supply?

I’m a research hydrologist, so I focus on hydrological impacts of atmospheric rivers. Although they can lead to flood hazards, atmospheric rivers are also essential to the Western water supply. Atmospheric rivers have been responsible for ending more than a third of the region’s major droughts, including the severe California drought of 2012-16.

Atmospheric rivers provide an average of 30% to 50% of the West Coast’s annual precipitation.

They also contribute to the snowpack, which provides a significant portion of California’s year-round water supply.

In an average year, one to two extreme atmospheric rivers with snow will be the dominant contributors to the snowpack in the Sierra Nevada. Together, atmospheric rivers will contribute about 30% to 40% of an average season’s total snow accumulation there.

A dam spillway with a full reservoir behind it.
After several winter storms brought record snowfall to California’s Sierra Nevada in early 2023, Lake Oroville, California’s second-largest reservoir, was at 100% capacity. The previous year, much of the state had faced water restrictions. Justin Sullivan/Getty Images

That’s why my colleagues at the Center for Western Weather and Water Extremes at the Scripps Institution of Oceanography, part of the University of California, San Diego, work on improving atmospheric river forecasts and predictions. Water managers need to be able to regulate reservoirs and figure out how much water they can save for the dry season while still leaving room in the reservoirs to manage flood risk from future storms.

How is global warming affecting atmospheric rivers?

As global temperatures rise in the future, we can expect more intense atmospheric rivers, leading to an increase in heavy and extreme precipitation events.

My research also shows that more atmospheric rivers are likely to occur concurrently during already wet conditions. So, the chance of extreme flooding also increases. Another study, by scientists from the University of Washington, suggests that there will be a seasonal shift to more atmospheric rivers earlier in the rainy season.

There will likely also be more year-to-year variability in the total annual precipitation, particularly in California, as a study by my colleagues at the Center for Western Weather and Water Extremes projects.

Qian Cao, Hydrologist, Center For Western Weather and Water Extremes, University of California, San Diego

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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PBS have also presented an item on what is an atmospheric river. Their article starts:

Forecasters warned of dangerous flooding, heavy mountain snow and a heightened risk of mudslides and avalanches Feb. 4-6, 2024, as a powerful atmospheric river took aim at California. It’s the latest in a series of atmospheric rivers to bring extreme rainfall to the West Coast.

Qian Cao

I sense many things are changing and the challenge is not to let one’s imagination go into overdrive.

Being wrong can be right!

Another very interesting post courtesy of The Conversation.

First of all, let me quote the opening two paragraphs from the WikiPedia entry on ‘intellectual humility’:

Intellectual humility is the acceptance that one’s beliefs and opinions could be wrong. Other characteristics that may accompany intellectual humility include a low concern for status and an acceptance of one’s intellectual limitations.

Intellectual humility (IH) is often described as an intellectual virtue. It is considered along with other perceived virtues and vices such as open-mindedness, intellectual courage, arrogance, vanity, and servility. It can be understood as lying between the opposite extremes of intellectual arrogance/dogmatism and intellectual servility/diffidence/timidity.

Now to the article that was published by The Conversation.

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The curious joy of being wrong – intellectual humility means being open to new information and willing to change your mind

Sometimes the evidence points you in a new direction. Schon/Moment via Getty Images

Daryl Van Tongeren, Hope College

Mark Twain apocryphally said, “I’m in favor of progress; it’s change I don’t like.” This quote pithily underscores the human tendency to desire growth while also harboring strong resistance to the hard work that comes with it. I can certainly resonate with this sentiment.

I was raised in a conservative evangelical home. Like many who grew up in a similar environment, I learned a set of religious beliefs that framed how I understood myself and the world around me. I was taught that God is loving and powerful, and God’s faithful followers are protected. I was taught that the world is fair and that God is good. The world seemed simple and predictable – and most of all, safe.

These beliefs were shattered when my brother unexpectedly passed away when I was 27 years old. His death at 34 with three young children shocked our family and community. In addition to reeling with grief, some of my deepest assumptions were challenged. Was God not good or not powerful? Why didn’t God save my brother, who was a kind and loving father and husband? And how unfair, uncaring and random is the universe?

This deep loss started a period where I questioned all of my beliefs in light of the evidence of my own experiences. Over a considerable amount of time, and thanks to an exemplary therapist, I was able to revise my worldview in a way that felt authentic. I changed my mind, about a lot things. The process sure wasn’t pleasant. It took more sleepless nights than I care to recall, but I was able to revise some of my core beliefs.

I didn’t realize it then, but this experience falls under what social science researchers call intellectual humility. And honestly, it is probably a large part of why, as a psychology professor, I am so interested in studying it. Intellectual humility has been gaining more attention, and it seems critically important for our cultural moment, when it’s more common to defend your position than change your mind.

What it means to be intellectually humble

Intellectual humility is a particular kind of humility that has to do with beliefs, ideas or worldviews. This is not only about religious beliefs; it can show up in political views, various social attitudes, areas of knowledge or expertise or any other strong convictions. It has both internal- and external-facing dimensions.

Within yourself, intellectual humility involves awareness and ownership of the limitations and biases in what you know and how you know it. It requires a willingness to revise your views in light of strong evidence.

Interpersonally, it means keeping your ego in check so you can present your ideas in a modest and respectful manner. It calls for presenting your beliefs in ways that are not defensive and admitting when you’re wrong. It involves showing that you care more about learning and preserving relationships than about being “right” or demonstrating intellectual superiority.

Another way of thinking about humility, intellectual or otherwise, is being the right size in any given situation: not too big (which is arrogance), but also not too small (which is self-deprecation).

male standing with mic, seated audience, in a casual business seminar
Having confidence in your area of expertise is different than thinking you know it all about everything. Morsa Images/DigitalVision via Getty Images

I know a fair amount about psychology, but not much about opera. When I’m in professional settings, I can embrace the expertise that I’ve earned over the years. But when visiting the opera house with more cultured friends, I should listen and ask more questions, rather than confidently assert my highly uninformed opinion.

Four main aspects of intellectual humility include being:

  • Open-minded, avoiding dogmatism and being willing to revise your beliefs.
  • Curious, seeking new ideas, ways to expand and grow, and changing your mind to align with strong evidence.
  • Realistic, owning and admitting your flaws and limitations, seeing the world as it is rather than as you wish it to be.
  • Teachable, responding nondefensively and changing your behavior to align with new knowledge.

Intellectual humility is often hard work, especially when the stakes are high.

Starting with the admission that you, like everyone else, have cognitive biases and flaws that limit how much you know, intellectual humility might look like taking genuine interest in learning about your relative’s beliefs during a conversation at a family get-together, rather than waiting for them to finish so you can prove them wrong by sharing your – superior – opinion.

It could look like considering the merits of an alternative viewpoint on a hot-button political issue and why respectable, intelligent people might disagree with you. When you approach these challenging discussions with curiosity and humility, they become opportunities to learn and grow.

Why intellectual humility is an asset

Though I’ve been studying humility for years, I’ve not yet mastered it personally. It’s hard to swim against cultural norms that reward being right and punish mistakes. It takes constant work to develop, but psychological science has documented numerous benefits.

First, there are social, cultural and technological advances to consider. Any significant breakthrough in medicine, technology or culture has come from someone admitting they didn’t know something – and then passionately pursuing knowledge with curiosity and humility. Progress requires admitting what you don’t know and seeking to learn something new.

animated people talking over a meal
Intellectual humility can make conversations less adversarial. Compassionate Eye Foundation/Gary Burchell/DigitalVision via Getty Images

Relationships improve when people are intellectually humble. Research has found that intellectual humility is associated with greater tolerance toward people with whom you disagree.

For example, intellectually humble people are more accepting of people who hold differing religious and political views. A central part of it is an openness to new ideas, so folks are less defensive to potentially challenging perspectives. They’re more likely to forgive, which can help repair and maintain relationships.

Finally, humility helps facilitate personal growth. Being intellectually humble allows you to have a more accurate view of yourself.

When you can admit and take ownership of your limitations, you can seek help in areas where you have room to grow, and you’re more responsive to information. When you limit yourself to only doing things the way you’ve always done them, you miss out on countless opportunities for growth, expansion and novelty – things that strike you with awe, fill you with wonder and make life worth living.

Humility can unlock authenticity and personal development.

Humility doesn’t mean being a pushover

Despite these benefits, sometimes humility gets a bad rap. People can have misconceptions about intellectual humility, so it’s important to dispel some myths.

Intellectual humility isn’t lacking conviction; you can believe something strongly until your mind is changed and you believe something else. It also isn’t being wishy-washy. You should have a high bar for what evidence you require to change your mind. It also doesn’t mean being self-deprecating or always agreeing with others. Remember, it’s being the right size, not too small.

Researchers are working hard to validate reliable ways to cultivate intellectual humility. I’m part of a team that is overseeing a set of projects designed to test different interventions to develop intellectual humility.

Some scholars are examining different ways to engage in discussions, and some are exploring the role of enhancing listening. Others are testing educational programs, and still others are looking at whether different kinds of feedback and exposure to diverse social networks might boost intellectual humility.

Prior work in this area suggests that humility can be cultivated, so we’re excited to see what emerges as the most promising avenues from this new endeavor.

There was one other thing that religion taught me that was slightly askew. I was told that too much learning could be ruinous; after all, you wouldn’t want to learn so much that you might lose your faith.

But in my experience, what I learned through loss may have salvaged a version of my faith that I can genuinely endorse and feels authentic to my experiences. The sooner we can open our minds and stop resisting change, the sooner we’ll find the freedom offered by humility.

Daryl Van Tongeren, Associate Professor of Psychology, Hope College

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Nothing more to add to this most interesting article.

The Winter solstice

We pass from 2023 into 2024.

So here we are, 2024, and the year when I become 80! However, I still have eleven months before that happens. Like an amazing number of people, I do not really think long about this New Year but there are plenty that do.

Here is an article that explains much more. It is from The Conversation.

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What winter solstice rituals tell us about indigenous people

The Blackfeet always faced their tipis towards the rising sun, including on winter solstice. Beinecke Library via Wikimedia Commons, CC BY

Rosalyn R. LaPier, University of Montana

On the day of winter solstice, many Native American communities will hold religious ceremonies or community events.

The winter solstice is the day of the year when the Northern Hemisphere has the fewest hours of sunlight and the Southern Hemisphere has the most. For indigenous peoples, it has been a time to honor their ancient sun deity. They passed their knowledge down to successive generations through complex stories and ritual practices.

As a scholar of the environmental and Native American religion, I believe, there is much to learn from ancient religious practices.

Ancient architecture

For decades, scholars have studied the astronomical observations that ancient indigenous people made and sought to understand their meaning.

One such place was at Cahokia, near the Mississippi River in what is now Illinois across from St. Louis.

The Cahokia mounds. Doug Kerr, CC BY-SA

In Cahokia, indigenous people built numerous temple pyramids or mounds, similar to the structures built by the Aztecs in Mexico, over a thousand years ago. Among their constructions, what most stands out is an intriguing structure made up of wooden posts arranged in a circle, known today as “Woodhenge.”

To understand the purpose of Woodhenge, scientists watched the sun rise from this structure on winter solstice. What they found was telling: The sun aligned with both Woodhenge and the top of a temple mound – a temple built on top of a pyramid with a flat top – in the distance. They also found that the sun aligns with a different temple mound on summer solstice.

Archaeological evidence suggests that the people of Cahokia venerated the sun as a deity. Scholars believe that ancient indigenous societies observed the solar system carefully and wove that knowledge into their architecture.

Scientists have speculated that the Cahokia held rituals to honor the sun as a giver of life and for the new agricultural year.

Complex understandings

Zuni Pueblo is a contemporary example of indigenous people with an agricultural society in western New Mexico. They grow corn, beans, squash, sunflowers and more. Each year they hold annual harvest festivals and numerous religious ceremonies, including at the winter solstice.

At the time of the winter solstice they hold a multiday celebration, known as the Shalako festival. The days for the celebration are selected by the religious leaders. The Zuni are intensely private, and most events are not for public viewing.

But what is shared with the public is near the end of the ceremony, when six Zuni men dress up and embody the spirit of giant bird deities. These men carry the Zuni prayers for rain “to all the corners of the earth.” The Zuni deities are believed to provide “blessings” and “balance” for the coming seasons and agricultural year.

As religion scholar Tisa Wenger writes, “The Zuni believe their ceremonies are necessary not just for the well-being of the tribe but for “the entire world.”

Winter games

Not all indigenous peoples ritualized the winter solstice with a ceremony. But that doesn’t mean they didn’t find other ways to celebrate.

The Blackfeet tribe in Montana, where I am a member, historically kept a calendar of astronomical events. They marked the time of the winter solstice and the “return” of the sun or “Naatosi” on its annual journey. They also faced their tipis – or portable conical tents – east toward the rising sun.

They rarely held large religious gatherings in the winter. Instead the Blackfeet viewed the time of the winter solstice as a time for games and community dances. As a child, my grandmother enjoyed attending community dances at the time of the winter solstice. She remembered that each community held their own gatherings, with unique drumming, singing and dance styles.

Later, in my own research, I learned that the Blackfeet moved their dances and ceremonies during the early reservation years from times on their religious calendar to times acceptable to the U.S. government. The dances held at the time of the solstice were moved to Christmas Day or to New Year’s Eve.

The solstice. Divad, from Wikimedia Commons

Today, my family still spends the darkest days of winter playing card games and attending the local community dances, much like my grandmother did.

Although some winter solstice traditions have changed over time, they are still a reminder of indigenous peoples understanding of the intricate workings of the solar system. Or as the Zuni Pueblo’s rituals for all peoples of the earth demonstrate – of an ancient understanding of the interconnectedness of the world.

(This article is republished from The Conversation under a Creative Commons license. Read the original article.)

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Jean and I wish you all a Very Happy 2024. Please be safe and careful, and be happy!

Detecting fakes

Another good article from The Conversation.

I make no apologies for returning to the subject of scams and fakes. Because the advances in the equipment we have for viewing the internet are growing appreciably, and quickly.

We should include scams in this topic. Just a couple of days ago I had a text on my cell-phone that purported to have come from the United States Post Office, the USPS, and at first I was taken in. Luckily I left it for a while and then discovered it was a scam.

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No, you’re not that good at detecting fake videos − 2 misinformation experts explain why and how you can develop the power to resist these deceptions

By

  1. Sam Wineburg Professor of Education and (by courtesy) History, Stanford University
  2. Michael Caulfield Research Scientist, Center for an Informed Public, University of Washington
Are you sure you know what that emotionally jarring video clip really shows?
F.J. Jimenez/Moment via Getty Images

Sam Wineburg, Stanford University and Michael Caulfield, University of Washington

Someone tracking the conflict raging in the Middle East could have seen the following two videos on social media. The first shows a little boy hovering over his father’s dead body, whimpering in Arabic, “Don’t leave me.” The second purports to show a pregnant woman with her stomach slashed open and claims to document the testimony of a paramedic who handled victims’ bodies after Hamas’ attack in Israel on Oct. 7, 2023.

Even though these videos come from different sides of the Israel-Hamas war, what they share far exceeds what separates them. Because both videos, though real, have nothing to do with the events they claim to represent. The clip of the boy is from Syria in 2016; the one of the woman is from Mexico in 2018.

Cheap but effective fakes

Recent headlines warn of sophisticated, AI-driven deepfakes. But it is low-tech cheap fakes like these that fuel the latest round of disinformation. Cheap fakes are the Swiss army knife in the propagandist’s tool belt. Changing a date, altering a location or even repurposing a clip from a video game and passing it off as battlefield combat require little know-how yet effectively sow confusion.

The Israel-Hamas war has unleashed a flood of fake videos on social media.

The good news is that you can avoid being taken in by these ruses – not by examining the evidence closely, which is liable to mislead you, but by waiting until trusted sources verify what you’re looking at. This is often hard to do, however.

Most people are ill-equipped to detect this kind of trickery. Research that we review in our new book, “Verified: How to Think Straight, Get Duped Less, and Make Better Decisions about What to Believe Online,” shows that almost everyone falls for it.

In the largest survey of its kind, 3,446 high school students evaluated a video on social media that purported to show election fraud in the 2016 Democratic primary. Students could view the whole video, part of it or leave the footage to search the internet for information about it. Typing a few keywords into their browsers would have led students to articles from Snopes and the BBC debunking the video. Only three students – less than one-tenth of 1% – located the true source of the video, which had, in fact, been shot in Russia.

Your lying eyes

Why were students so consistently duped? The problem, we’ve found, is that many people, young and old alike, think they can look at something online and tell what it is. You don’t realize how easily your eyes can be deceived – especially by footage that triggers your emotions.

When an incendiary video dodges your prefrontal cortex and lands in your solar plexus, the first impulse is to share your outrage with others. What’s a better course of action? You might assume that it is to ask whether the clip is true or false. But a different question – rather, a set of related questions – is a better starting place.

  • Do you really know what you’re looking at?
  • Can you really tell whether the footage is from atrocities committed by Russian forces in the Donbas just because the headline blares it and you’re sympathetic to the Ukrainian cause?
  • Is the person who posted the footage an established reporter, someone who risks their status and prestige if it turns out to be fake, or some random person?
  • Is there a link to a longer video – the shorter the clip, the more you should be wary – or does it claim to speak for itself, even though the headline and caption leave little room for how to connect the dots?

These questions require no advanced knowledge of video forensics. They require you only to be honest with yourself. Your inability to answer these questions should be enough to make you realize that, no, you don’t really know what you’re looking at.

Patience is a powerful tool

Social media reports of “late-breaking news” are not likely to be reporting at all, but they are often pushed by rage merchants wrapping an interpretation around a YouTube video accompanied by lightning bolt emojis and strings of exclamation points. Reliable reporters need time to establish what happened. Rage merchants don’t. The con artist and the propagandist feed on the impatient. Your greatest information literacy superpower is learning to wait.

If there are legs to the video, rest assured you’re not the only one viewing it. There are many people, some of whom have mastered advanced techniques of video analysis, who are likely already analyzing it and trying to get to the bottom of it.

You won’t have to wait long to learn what they’ve found.

Sam Wineburg, Professor of Education and (by courtesy) History, Stanford University and Michael Caulfield, Research Scientist, Center for an Informed Public, University of Washington

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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I hope you found this of interest. We live in many ways in a really strange world; I am talking about the digital world, of course.

The expansion of the Universe

I am reproducing a recent article published by The Conversation.

It is a reflection of the latest research undertaken by NASA, it is beyond fascinating!

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The universe is expanding faster than theory predicts – physicists are searching for new ideas that might explain the mismatch

The James Webb Space Telescope’s deep field image shows a universe full of sparkling galaxies. NASA/STScI

Ryan Keeley, University of California, Merced

Astronomers have known for decades that the universe is expanding. When they use telescopes to observe faraway galaxies, they see that these galaxies are moving away from Earth.

To astronomers, the wavelength of light a galaxy emits is longer the faster the galaxy is moving away from us. The farther away the galaxy is, the more its light has shifted toward the longer wavelengths on the red side of the spectrum – so the higher the “redshift.”

Because the speed of light is finite, fast, but not infinitely fast, seeing something far away means we’re looking at the thing how it looked in the past. With distant, high-redshift galaxies, we’re seeing the galaxy when the universe was in a younger state. So “high redshift” corresponds to the early times in the universe, and “low redshift” corresponds to the late times in the universe.

But as astronomers have studied these distances, they’ve learned that the universe is not just expanding – its rate of expansion is accelerating. And that expansion rate is even faster than the leading theory predicts it should be, leaving cosmologists like me puzzled and looking for new explanations.

Dark energy and a cosmological constant

Scientists call the source of this acceleration dark energy. We’re not quite sure what drives dark energy or how it works, but we think its behavior could be explained by a cosmological constant, which is a property of spacetime that contributes to the expansion of the universe.

Albert Einstein originally came up with this constant – he marked it with a lambda in his theory of general relativity. With a cosmological constant, as the universe expands, the energy density of the cosmological constant stays the same.

Imagine a box full of particles. If the volume of the box increases, the density of particles would decrease as they spread out to take up all the space in the box. Now imagine the same box, but as the volume increases, the density of the particles stays the same.

It doesn’t seem intuitive, right? That the energy density of the cosmological constant does not decrease as the universe expands is, of course, very weird, but this property helps explain the accelerating universe.

A standard model of cosmology

Right now, the leading theory, or standard model, of cosmology is called “Lambda CDM.” Lambda denotes the cosmological constant describing dark energy, and CDM stands for cold dark matter. This model describes both the acceleration of the universe in its late stages as well as the expansion rate in its early days.

Specifically, the Lambda CDM explains observations of the cosmic microwave background, which is the afterglow of microwave radiation from when the universe was in a “hot, dense state” about 300,000 years after the Big Bang. Observations using the Planck satellite, which measures the cosmic microwave background, led scientists to create the Lambda CDM model.

Fitting the Lambda CDM model to the cosmic microwave background allows physicists to predict the value of the Hubble constant, which isn’t actually a constant but a measurement describing the universe’s current expansion rate.

But the Lambda CDM model isn’t perfect. The expansion rate scientists have calculated by measuring distances to galaxies, and the expansion rate as described in Lambda CDM using observations of the cosmic microwave background, don’t line up. Astrophysicists call that disagreement the Hubble tension.

An illustration showing the progression of the Universe's expansion after the Big Bang. The Universe is depicted as a cylindrical funnel with labels along the bottom showing the first stars, the development of planets, and now the dark energy acceleration
The universe is expanding faster than predicted by popular models in cosmology. NASA

The Hubble tension

Over the past few years, I’ve been researching ways to explain this Hubble tension. The tension may be indicating that the Lambda CDM model is incomplete and physicists should modify their model, or it could indicate that it’s time for researchers to come up with new ideas about how the universe works. And new ideas are always the most exciting things for a physicist.

One way to explain the Hubble tension is to modify the Lambda CDM model by changing the expansion rate at low redshift, at late times in the universe. Modifying the model like this can help physicists predict what sort of physical phenomena might be causing the Hubble tension.

For instance, maybe dark energy is not a cosmological constant but instead the result of gravity working in new ways. If this is the case, dark energy would evolve as the universe expands – and the cosmic microwave background, which shows what the universe looked like only a few years after its creation, would have a different prediction for the Hubble constant.

But, my team’s latest research has found that physicists can’t explain the Hubble tension just by changing the expansion rate in the late universe – this whole class of solutions falls short.

Developing new models

To study what types of solutions could explain the Hubble tension, we developed statistical tools that enabled us to test the viability of the entire class of models that change the expansion rate in the late universe. These statistical tools are very flexible, and we used them to match or mimic different models that could potentially fit observations of the universe’s expansion rate and might offer a solution to the Hubble tension.

The models we tested include evolving dark energy models, where dark energy acts differently at different times in the universe. We also tested interacting dark energy-dark matter models, where dark energy interacts with dark matter, and modified gravity models, where gravity acts differently at different times in the universe.

But none of these could fully explain the Hubble tension. These results suggest that physicists should study the early universe to understand the source of the tension.

Ryan Keeley, Postdoctoral Scholar in Physics, University of California, Merced

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Ryan Keeley explains it above. Hopefully most of you who read this understand the physics involved. Ryan has a website here.

As I said at the start it is beyond fascinating! In the truest sense, out of this world!

The history of Oxygen!

A fascinating subject.

We take it for granted! Of that I am sure. But the question of how oxygen first came to be built up in our atmosphere is fascinating. There was a recent article written by Elizabeth Swanner, who is Associate Professor of Geology, Iowa State University that was published in The Conversation. It makes for a very interesting read.

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A layered lake is a little like Earth’s early oceans − and lets researchers explore how oxygen built up in our atmosphere billions of years ago

Researchers sample water from various layers to analyze back in the lab. Elizabeth Swanner, CC BY-ND

Elizabeth Swanner, Iowa State University

Little Deming Lake doesn’t get much notice from visitors to Itasca State Park in Minnesota. There’s better boating on nearby Lake Itasca, the headwaters of the Mississippi River. My colleagues and I need to maneuver hundreds of pounds of equipment down a hidden path made narrow by late-summer poison ivy to launch our rowboats.

But modest Deming Lake offers more than meets the eye for me, a geochemist interested in how oxygen built up in the atmosphere 2.4 billion years ago. The absence of oxygen in the deep layers of Deming Lake is something this small body of water has in common with early Earth’s oceans.

On each of our several expeditions here each year, we row our boats out into the deepest part of the lake – over 60 feet (18 meters), despite the lake’s surface area being only 13 acres. We drop an anchor and connect our boats in a flotilla, readying ourselves for the work ahead.

Smooth lake with boats in the distance against woodsy shoreline
Researchers’ boats on Deming Lake. Elizabeth Swanner, CC BY-ND

Deming Lake is meromictic, a term from Greek that means only partially mixing. In most lakes, at least once a year, the water at the top sinks while the water at the bottom rises because of wind and seasonal temperature changes that affect water’s density. But the deepest waters of Deming Lake never reach the surface. This prevents oxygen in its top layer of water from ever mixing into its deep layer.

Less than 1% of lakes are meromictic, and most that are have dense, salty bottom waters. Deming Lake’s deep waters are not very salty, but of the salts in its bottom waters, iron is one of the most abundant. This makes Deming Lake one of the rarest types of meromictic lakes.

man seated in small boat wearing gloves injecting water into a collection tube
Postdoc researcher Sajjad Akam collects a water sample for chemical analysis back in the lab. Elizabeth Swanner, CC BY-ND

The lake surface is calm, and the still air is glorious on this cool, cloudless August morning. We lower a 2-foot-long water pump zip-tied to a cable attached to four sensors. The sensors measure the temperature, amount of oxygen, pH and amount of chlorophyll in the water at each layer we encounter. We pump water from the most intriguing layers up to the boat and fill a myriad of bottles and tubes, each destined for a different chemical or biological analysis.

My colleagues and I have homed in on Deming Lake to explore questions about how microbial life adapted to and changed the environmental conditions on early Earth. Our planet was inhabited only by microbes for most of its history. The atmosphere and the oceans’ depths didn’t have much oxygen, but they did have a lot of iron, just like Deming Lake does. By investigating what Deming Lake’s microbes are doing, we can better understand how billions of years ago they helped to transform the Earth’s atmosphere and oceans into what they’re like now.

Layer by layer, into the lake

Two and a half billion years ago, ocean waters had enough iron to form today’s globally distributed rusty iron deposits called banded iron formations that supply iron for the modern global steel industry. Nowadays, oceans have only trace amounts of iron but abundant oxygen. In most waters, iron and oxygen are antithetical. Rapid chemical and biological reactions between iron and oxygen mean you can’t have much of one while the other is present.

The rise of oxygen in the early atmosphere and ocean was due to cyanobacteria. These single-celled organisms emerged at least 2.5 billion years ago. But it took roughly 2 billion years for the oxygen they produce via photosynthesis to build up to levels that allowed for the first animals to appear on Earth.

water concentrated on a filter looks pale green
Chlorophyll colors water from the lake slightly green. Elizabeth Swanner, CC BY-ND

At Deming Lake, my colleagues and I pay special attention to the water layer where the chlorophyll readings jump. Chlorophyll is the pigment that makes plants green. It harnesses sunlight energy to turn water and carbon dioxide into oxygen and sugars. Nearly 20 feet (6 meters) below Deming’s surface, the chlorophyll is in cyanobacteria and photosynthetic algae, not plants.

But the curious thing about this layer is that we don’t detect oxygen, despite the abundance of these oxygen-producing organisms. This is the depth where iron concentrations start to climb to the high levels present at the lake’s bottom.

This high-chlorophyll, high-iron and low-oxygen layer is of special interest to us because it might help us understand where cyanobacteria lived in the ancient ocean, how well they were growing and how much oxygen they produced.

We suspect the reason cyanobacteria gather at this depth in Deming Lake is that there is more iron there than at the top of the lake. Just like humans need iron for red blood cells, cyanobacteria need lots of iron to help catalyze the reactions of photosynthesis.

A likely reason we can’t measure any oxygen in this layer is that in addition to cyanobacteria, there are a lot of other bacteria here. After a good long life of a few days, the cyanobacteria die, and the other bacteria feed on their remains. These bacteria rapidly use up any oxygen produced by still photosynthesizing cyanobacteria the way a fire does as it burns through wood.

We know there are lots of bacteria here based on how cloudy the water is, and we see them when we inspect a drop of this water under a microscope. But we need another way to measure photosynthesis besides measuring oxygen levels.

Long-running lakeside laboratory

The other important function of photosynthesis is converting carbon dioxide into sugars, which eventually are used to make more cells. We need a way to track whether new sugars are being made, and if they are, whether it’s by photosynthetic cyanobacteria. So we fill glass bottles with samples of water from this lake layer and seal them tight with rubber stoppers.

We drive the 3 miles back to the Itasca Biological Station and Laboratories where we will set up our experiments. The station opened in 1909 and is home base for us this week, providing comfy cabins, warm meals and this laboratory space.

In the lab, we inject our glass bottle with carbon dioxide that carries an isotopic tracer. If cyanobacteria grow, their cells will incorporate this isotopic marker.

We had a little help to formulate our questions and experiments. University of Minnesota students attending summer field courses collected decades worth of data in Itasca State Park. A diligent university librarian digitized thousands of those students’ final papers.

My students and I pored over the papers concerning Deming Lake, many of which tried to determine whether the cyanobacteria in the chlorophyll-rich layer are doing photosynthesis. While most indicated yes, those students were measuring only oxygen and got ambiguous results. Our use of the isotopic tracer is trickier to implement but will give clearer results.

woman holds a clear plastic bag aloft, she and man are seated in boat
Graduate students Michelle Chamberlain and Zackry Stevenson about to sink the bottles for incubation in Deming Lake. Elizabeth Swanner, CC BY-ND

That afternoon, we’re back on the lake. We toss an anchor; attached to its rope is a clear plastic bag holding the sealed bottles of lake water now amended with the isotopic tracer. They’ll spend the night in the chlorophyll-rich layer, and we’ll retrieve them after 24 hours. Any longer than that and the isotopic label might end up in the bacteria that eat the dying cyanobacteria instead of the cyanobacteria themselves. We tie off the rope to a floating buoy and head back to the station’s dining hall for our evening meal.

Iron, chlorophyll, oxygen

The next morning, as we wait for the bottles to finish their incubation, we collect water from the different layers of the lake and add some chemicals that kill the cells but preserve their bodies. We’ll look at these samples under the microscope to figure out how many cyanobacteria are in the water, and we’ll measure how much iron is inside the cyanobacteria.

That’s easier said than done, because we have to first separate all the “needles” (cyanobacteria) from the “hay” (other cells) and then clean any iron off the outside of the cyanobacteria. Back at Iowa State University, we’ll shoot the individual cells one by one into a flame that incinerates them, which liberates all the iron they contain so we can measure it.

rowboat with one woman in it on a lake with woodsy shoreline
Biogeochemist Katy Sparrow rows a research vessel to shore. Elizabeth Swanner, CC BY-ND

Our scientific hunch, or hypothesis, is that the cyanobacteria that live in the chlorophyll- and iron-rich layer will contain more iron than cyanobacteria that live in the top lake layer. If they do, it will help us establish that greater access to iron is a motive for living in that deeper and dimmer layer.

These experiments won’t tell the whole story of why it took so long for Earth to build up oxygen, but they will help us to understand a piece of it – where oxygen might have been produced and why, and what happened to oxygen in that environment.

Deming Lake is quickly becoming its own attraction for those with a curiosity about what goes on beneath its tranquil surface – and what that might be able to tell us about how new forms of life took hold long ago on Earth.

Elizabeth Swanner, Associate Professor of Geology, Iowa State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Nothing I can add to this very erudite article. Please read it and be fascinated by the findings.

Keeping healthy in old age.

One has to work at it!

For most of us these days old age is part of the scene (and I am classifying old age as being over 70 years). Here are a few facts from the website of the World Health Organization.

Key facts

  • Worldwide obesity has nearly tripled since 1975.
  • In 2016, more than 1.9 billion adults, 18 years and older, were overweight. Of these over 650 million were obese.
  • 39% of adults aged 18 years and over were overweight in 2016, and 13% were obese.
  • Most of the world’s population live in countries where overweight and obesity kills more people than underweight.
  • 39 million children under the age of 5 were overweight or obese in 2020.
  • Over 340 million children and adolescents aged 5-19 were overweight or obese in 2016.
  • Obesity is preventable.

What are obesity and overweight Overweight and obesity are defined as abnormal or excessive fat accumulation that may impair health.

Body mass index (BMI) is a simple index of weight-for-height that is commonly used to classify overweight and obesity in adults. It is defined as a person’s weight in kilograms divided by the square of his height in meters (kg/m2).

Adults

For adults, WHO defines overweight and obesity as follows:

  • overweight is a BMI greater than or equal to 25; and
  • obesity is a BMI greater than or equal to 30.

BMI provides the most useful population-level measure of overweight and obesity as it is the same for both sexes and for all ages of adults. However, it should be considered a rough guide because it may not correspond to the same degree of fatness in different individuals.

World Health Organisation

This is the link for anyone who wants to use the BMI Calculator.

Now this is not a post about obesity or being overweight. It is a post taken from The Conversation about staying as healthy as one can in one’s older years.

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Steep physical decline with age is not inevitable – here’s how strength training can change the trajectory

Resistance training can take many forms and can be individualized to suit a person’s needs as they age. Jamie Grill/Tetra Images via Getty Images

Zachary Gillen, Mississippi State University

Raise your hand if you regularly find yourself walking up a flight of stairs. What about carrying heavy bags of groceries? How about picking up your child or grandchild? Most of us would raise our hands to doing at least one of those weekly, or even daily.

As people age, it can become more and more difficult to perform some physical tasks, even those that are normal activities of daily living. However, prioritizing physical fitness and health as you get older can help you go through your normal day-to-day routine without feeling physically exhausted at the end of the day.

It can also help you continue to have special memories with your family and loved ones that you might not have been able to have if you weren’t physically active. For example, I ran two half-marathons with my dad when he was in his 60s!

I am an exercise physiologist who studies how people can use resistance training to improve human performance, whether it be in sports and other recreational settings, in everyday life, or both. I am also a certified strength and conditioning specialist. My career has given me the opportunity to design exercise programs for kids, college athletes and elderly adults.

Staying physically active as you get older doesn’t need to include running a half-marathon or trying to be a bodybuilder; it could be as simple as trying to get through the day without feeling winded after you go up a flight of stairs. Although our muscles naturally get weaker as we age, there are ways we can combat that to help improve quality of life as we get older.

Man in his 60s, a middle-aged woman and a middle-aged man, all wearing race medals and running gear.
From left are the author’s father, who was age 61 at the time, the author’s wife and the author after completing the Lincoln Half Marathon. Zachary Gillen, CC BY-NC-ND

Muscle loss and chronic disease

One of the most important parts of exercise programming, no matter who I am working with, is proper resistance training to build muscle strength. Some amount of age-related loss of muscle function is normal and inevitable. But by incorporating resistance training that is appropriate and safe at any ability level, you can slow down the rate of decline and even prevent some loss of muscle function.

The medical term for a condition that involves age-related loss of muscle function and mass is sarcopenia. Sarcopenia can begin as early as age 40, but it tends to be more common in adults age 60 and older. Sarcopenia is associated with a number of health issues such as increased risk of falling, cardiovascular disease and metabolic disease, among others.

In one of our team’s previous studies, we saw that otherwise healthy individuals with sarcopenia had issues delivering vital nutrients to muscle. This could lead to greater likelihood of various diseases, such as Type 2 diabetes, and slow down recovery from exercise.

Recent estimates suggest that sarcopenia affects 10% to 16% of the elderly population worldwide. But even if a person doesn’t have clinically diagnosed sarcopenia, they may still have some of the underlying symptoms that, if not dealt with, could lead to sarcopenia.

Strength training is key

So the question is, what can be done to reverse this decline?

Recent evidence suggests that one of the key factors leading to sarcopenia is low muscle strength. In other words, combating or reversing sarcopenia, or both, may be best done with a proper resistance-training program that prioritizes improving strength. In fact, the decline in muscle strength seems to occur at a much faster rate than the decline in muscle size, underscoring the importance of proper strength training as people age.

Chart showing the general pattern for changes in muscle strength and size across stage of life.
Typical age-related changes in muscle strength and size with and without strength training. Zachary Gillen

Continuing to regularly strength train with moderate to heavy weights has been shown to be not only effective at combating the symptoms of sarcopenia but also very safe when done properly. The best way to make sure you are strength training properly is to seek out guidance from a qualified individual such as a personal trainer or strength and conditioning specialist.

Despite the clear benefits of strength training, it’s been shown that only about 13% of Americans age 50 and older do some form of strength training at least twice a week.

Finding what works for you

So how does a person properly strength train as they age?

The National Strength and Conditioning Association, a leading organization in advancing strength and conditioning around the world, states that for older adults, two to three days per week of strength training can be incredibly helpful for maintaining healthy muscle and bone and combating a number of chronic conditions.

The organization recommends that these workouts involve one to two exercises involving multiple joints per major muscle group, with six to 12 repetitions per set. These are done at an intensity of 50% to 85% of what’s known as one-repetition maximum – the most weight you could handle for a single repetition – with the exception of body weight exercises that use one’s own body weight as the resistance, such as pushups.

I would also recommend resting for about two to three minutes between sets, or even up to five minutes if the set was challenging. For older adults, particularly those age 60 and older, the National Strength and Conditioning Association guidelines suggest that a program like this be performed two to three days per week, with 24 to 48 hours between sessions.

An example of a strength training routine for older adults based on the National Strength and Conditioning Association guidelines

There are a great variety of exercises that could be done interchangeably in a strength training program like this.

ExerciseNumber of setsRepetitions per setIntensity
Barbell squat3670-85%
Barbell bench press3670-85%
Dumbbell lunges38 per leg50-70%
Dumbbell bent over row31050-70%
Double-leg hops212Body weight
Pushups212Body weight

Table: The Conversation Source: Zachary Gillen Get the data Created with Datawrapper

Making life’s tasks lighter

The guidelines above are only one example out of many options, but they provide a framework that you can use to build your own program. However, I would highly recommend seeking out a professional in the field to give specific exercise programming advice that can be tailored to your own needs and goals as you age.

Following such a program would give your muscles an excellent stimulus to enhance strength, while also allowing enough recovery, a very important consideration as people age. You might think it looks like a huge time commitment, but an exercise routine like this can be done in less than an hour. This means that in less than three hours of strength training per week you can help improve your muscle health and reduce the risk of getting sarcopenia and associated health issues.

It’s also important to note that there is no one right way to do resistance training, and it needn’t involve traditional weight equipment. Group classes like Pilates and yoga or those that involve circuit training and work with resistance bands can all produce similar results. The key is to get out and exercise regularly, whatever that entails.

Zachary Gillen, Assistant Professor of Exercise Physiology, Mississippi State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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My wife, Jean, was diagnosed with Parkinson’s Disease (PD) in December, 2015. Many of you know that.

Fortunately at our local Club Northwest there was a group of PD sufferers who twice a week held a ‘Rock Steady Class’ under the instruction of a professional coach; Jean joined the group. It was a brilliant move for Jean and she gets a huge amount of care from being with them.

Luckily for me having to drive Jean into Club Northwest it made sense for me to sign up to a fitness class at the same time so I am put through a regular fitness routine under the coaching of Bruce. Plus I try and go bike riding three times a week.

In other words, we both try and stay as fit as we can.

The brain

A fascinating account

I was struggling with the post for tomorrow and then saw this article on The Conversation. It may not be everyone’s cup of tea but nevertheless I find it sufficiently interesting to publish it.

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Psychedelics plus psychotherapy can trigger rapid changes in the brain − new research at the level of neurons is untangling how

New research hints at how psychedelics can trigger rapid, lasting change. wildpixel/iStock via Getty Images Plus

Edmund S. Higgins, Medical University of South Carolina

The human brain can change – but usually only slowly and with great effort, such as when learning a new sport or foreign language, or recovering from a stroke. Learning new skills correlates with changes in the brain, as evidenced by neuroscience research with animals and functional brain scans in people. Presumably, if you master Calculus 1, something is now different in your brain. Furthermore, motor neurons in the brain expand and contract depending on how often they are exercised – a neuronal reflection of “use it or lose it.”

People may wish their brains could change faster – not just when learning new skills, but also when overcoming problems like anxiety, depression and addictions.

Clinicians and scientists know there are times the brain can make rapid, enduring changes. Most often, these occur in the context of traumatic experiences, leaving an indelible imprint on the brain.

But positive experiences, which alter one’s life for the better, can occur equally as fast. Think of a spiritual awakening, a near-death experience or a feeling of awe in nature.

a road splits in the woods, sun shines through green leafy trees
A transformative experience can be like a fork in the road, changing the path you are on. Westend61 via Getty Images

Social scientists call events like these psychologically transformative experiences or pivotal mental states. For the rest of us, they’re forks in the road. Presumably, these positive experiences quickly change some “wiring” in the brain.

How do these rapid, positive transformations happen? It seems the brain has a way to facilitate accelerated change. And here’s where it gets really interesting: Psychedelic-assisted psychotherapy appears to tap into this natural neural mechanism.

Psychedelic-assisted psychotherapy

Those who’ve had a psychedelic experience usually describe it as a mental journey that’s impossible to put into words. However, it can be conceptualized as an altered state of consciousness with distortions of perception, modified sense of self and rapidly changing emotions. Presumably there is a relaxation of the higher brain control, which allows deeper brain thoughts and feelings to emerge into conscious awareness.

Psychedelic-assisted psychotherapy combines the psychology of talk therapy with the power of a psychedelic experience. Researchers have described cases in which subjects report profound, personally transformative experiences after one six-hour session with the psychedelic substance psilocybin, taken in conjunction with psychotherapy. For example, patients distressed about advancing cancer have quickly experienced relief and an unexpected acceptance of the approaching end. How does this happen?

glowing green tendrils of a neuron against a black background
Neuronal spines are the little bumps along the spreading branches of a neuron. Patrick Pla via Wikimedia Commons, CC BY-SA

Research suggests that new skills, memories and attitudes are encoded in the brain by new connections between neurons – sort of like branches of trees growing toward each other. Neuroscientists even call the pattern of growth arborization.

Researchers using a technique called two-photon microscopy can observe this process in living cells by following the formation and regression of spines on the neurons. The spines are one half of the synapses that allow for communication between one neuron and another.

Scientists have thought that enduring spine formation could be established only with focused, repetitive mental energy. However, a lab at Yale recently documented rapid spine formation in the frontal cortex of mice after one dose of psilocybin. Researchers found that mice given the mushroom-derived drug had about a 10% increase in spine formation. These changes had occurred when examined one day after treatment and endured for over a month.

diagram of little bumps along a neuron, enlarged at different scales
Tiny spines along a neuron’s branches are a crucial part of how one neuron receives a message from another. Edmund S. Higgins

A mechanism for psychedelic-induced change

Psychoactive molecules primarily change brain function through the receptors on the neural cells. The serotonin receptor 5HT, the one famously tweaked by antidepressants, comes in a variety of subtypes. Psychedelics such as DMT, the active chemical in the plant-based psychedelic ayahuasca, stimulate a receptor cell type, called 5-HT2A. This receptor also appears to mediate the hyperplastic states when a brain is changing quickly.

These 5-HT2A receptors that DMT activates are not only on the neuron cell surface but also inside the neuron. It’s only the 5-HT2A receptor inside the cell that facilitates rapid change in neuronal structure. Serotonin can’t get through the cell membrane, which is why people don’t hallucinate when taking antidepressants like Prozac or Zoloft. The psychedelics, on the other hand, slip through the cell’s exterior and tweak the 5-HT2A receptor, stimulating dendritic growth and increased spine formation.

Here’s where this story all comes together. In addition to being the active ingredient in ayahuasca, DMT is an endogenous molecule synthesized naturally in mammalian brains. As such, human neurons are capable of producing their own “psychedelic” molecule, although likely in tiny quantities. It’s possible the brain uses its own endogenous DMT as a tool for change – as when forming dendritic spines on neurons – to encode pivotal mental states. And it’s possible psychedelic-assisted psychotherapy uses this naturally occurring neural mechanism to facilitate healing.

A word of caution

In her essay collection “These Precious Days,” author Ann Patchett describes taking mushrooms with a friend who was struggling with pancreatic cancer. The friend had a mystical experience and came away feeling deeper connections to her family and friends. Patchett, on the other hand, said she spent eight hours “hacking up snakes in some pitch-black cauldron of lava at the center of the Earth.” It felt like death to her.

Psychedelics are powerful, and none of the classic psychedelic drugs, such as LSD, are approved yet for treatment. The U.S. Food and Drug Administration in 2019 did approve ketamine, in conjunction with an antidepressant, to treat depression in adults. Psychedelic-assisted psychotherapy with MDMA (often called ecstasy or molly) for PTSD and psilocybin for depression are in Phase 3 trials.

Edmund S. Higgins, Affiliate Associate Professor of Psychiatry & Family Medicine, Medical University of South Carolina

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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This is not for the innocents and it requires someone of the ilk of Professor Higgins to advise.

Plus one needs to stay close to the U.S. Food and Drug Administration. To close, I will repeat the phrase above, psychedelics are powerful.

Dogs and scents

A fascinating article about our unique body odour.

I was researching stories that I could republish and was concentrating at first on The Conversation. Then I saw the post for today and went no further. It is primarily about the odour that each of us has.

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Your unique body odor could identify who you are and provide insights into your health – all from the touch of a hand

The scent emitted from your hands could offer clues about who you are. Siro Rodenas Cortes/Moment via Getty Images

Chantrell Frazier, Framingham State University; Kenneth G. Furton, Florida International University, and Vidia A. Gokool, Lawrence Livermore National Laboratory

From the aroma of fresh-cut grass to the smell of a loved one, you encounter scents in every part of your life. Not only are you constantly surrounded by odor, you’re also producing it. And it is so distinctive that it can be used to tell you apart from everyone around you.

Your scent is a complex product influenced by many factors, including your genetics. Researchers believe that a particular group of genes, the major histocompatibility complex, play a large role in scent production. These genes are involved in the body’s immune response and are believed to influence body odor by encoding the production of specific proteins and chemicals.

But your scent isn’t fixed once your body produces it. As sweat, oils and other secretions make it to the surface of your skin, microbes break down and transform these compounds, changing and adding to the odors that make up your scent. This scent medley emanates from your body and settles into the environments around you. And it can be used to track, locate or identify a particular person, as well as distinguish between healthy and unhealthy people.

We are researchers who specialize in studying human scent through the detection and characterization of gaseous chemicals called volatile organic compounds. These gases can relay an abundance of information for both forensic researchers and health care providers.

Science of body odor

When you are near another person, you can feel their body heat without touching them. You may even be able to smell them without getting very close. The natural warmth of the human body creates a temperature differential with the air around it. You warm up the air nearest to you, while air that’s farther away remains cool, creating warm currents of air that surround your body.

Researchers believe that this plume of air helps disperse your scent by pushing the millions of skin cells you shed over the course of a day off your body and into the environment. These skin cells act as boats or rafts carrying glandular secretions and your resident microbes – a combination of ingredients that emit your scent – and depositing them in your surroundings.

Your scent is composed of the volatile organic compounds present in the gases emitted from your skin. These gases are the combination of sweat, oils and trace elements exuded from the glands in your skin. The primary components of your odor depend on internal factors such as your race, ethnicity, biological sex and other traits. Secondary components waver based on factors like stress, diet and illness. And tertiary components from external sources like perfumes and soaps build on top of your distinguishable odor profile.

Identity of scent

With so many factors influencing the scent of any given person, your body odor can be used as an identifying feature. Scent detection canines searching for a suspect can look past all the other odors they encounter to follow a scent trail left behind by the person they are pursuing. This practice relies on the assumption that each person’s scent is distinct enough that it can be distinguished from other people’s.

Researchers have been studying the discriminating potential of human scent for over three decades. A 1988 experiment demonstrated that a dog could distinguish identical twins living apart and exposed to different environmental conditions by their scent alone. This is a feat that could not be accomplished using DNA evidence, as identical twins share the same genetic code.

The field of human scent analysis has expanded over the years to further study the composition of human scent and how it can be used as a form of forensic evidence. Researchers have seen differences in human odor composition that can be classified based on sex, gender, race and ethnicity. Our research team’s 2017 study of 105 participants found that specific combinations of 15 volatile organic compounds collected from people’s hands could distinguish between race and ethnicity with an accuracy of 72% for whites, 82% for East Asians and 67% for Hispanics. Based on a combination of 13 compounds, participants could be distinguished as male or female with an overall 80% accuracy.

Researchers have trained dogs to sniff out COVID-19 infections.

Researchers are also producing models to predict the characteristics of a person based on their scent. From a sample pool of 30 women and 30 men, our team built a machine learning model that could predict a person’s biological sex with 96% accuracy based on hand odor.

Scent of health

Odor research continues to provide insights into illnesses. Well-known examples of using scent in medical assessments include seizure and diabetic alert canines. These dogs can give their handlers time to prepare for an impending seizure or notify them when they need to adjust their blood glucose levels.

While these canines often work with a single patient known to have a condition that requires close monitoring, medical detection dogs can also indicate whether someone is ill. For example, researchers have shown that dogs can be trained to detect cancer in people. Canines have also been trained to detect COVID-19 infections at a 90% accuracy rate.

Similarly, our research team found that a laboratory analysis of hand odor samples could discriminate between people who are COVID-19 positive or negative with 75% accuracy.

Forensics of scent

Human scent offers a noninvasive method to collect samples. While direct contact with a surface like touching a doorknob or wearing a sweater provides a clear route for your scent to transfer to that surface, simply standing still will also transfer your odor into the surrounding area.

Although human scent has the potential to be a critical form of forensic evidence, it is still a developing field. Imagine a law enforcement officer collecting a scent sample from a crime scene in hopes that it may match with a suspect.

Further research into human scent analysis can help fill the gaps in our understanding of the individuality of human scent and how to apply this information in forensic and biomedical labs.

Chantrell Frazier, Assistant Professor of Chemistry and Food Science, Framingham State University; Kenneth G. Furton, Professor of Chemistry and Biochemistry, Florida International University, and Vidia A. Gokool, Postdoctoral Researcher, Lawrence Livermore National Laboratory

This article is republished from The Conversation under a Creative Commons license. Read the original article.

ooOOoo

This is so interesting and I, for one, learnt a great deal more about the human body and in particular the scent glands.

Plus, it was a joy to read about the role of canines in all of this.