My last post was about an accident that I had on the 17th November, last.
Jean is now back home; she came home on Friday, 13th December. However, every day we have a caregiver at home for part of the time. Jean is getting slowly better. I would estimate that at about one percent a day.
I am unsure as to the pattern of my posts. Whether I should go back to scheduling posts three times a week or publish posts on an ad-hoc basis. That will become clearer over the next few weeks.
I am going to start with publishing posts on an ad-hoc basis.
Meanwhile here in Merlin we have had loads of rain.
Bummer Creek
This is the creek that flows across the lower part of the property.
There is no question the world’s weather systems are changing. However, for folk who are not trained in this science it is all a bit mysterious. So thank goodness that The Conversation have not only got a scientist who does know what he is talking about but also they are very happy for it to be republished.
ooOOoo
Atmospheric rivers are shifting poleward, reshaping global weather patterns
Atmospheric rivers are long filaments of moisture that curve poleward. Several are visible in this satellite image. Bin Guan, NASA/JPL-Caltech and UCLA
Atmospheric rivers – those long, narrow bands of water vapor in the sky that bring heavy rain and storms to the U.S. West Coast and many other regions – are shifting toward higher latitudes, and that’s changing weather patterns around the world.
The shift is worsening droughts in some regions, intensifying flooding in others, and putting water resources that many communities rely on at risk. When atmospheric rivers reach far northward into the Arctic, they can also melt sea ice, affecting the global climate.
In a new study published in Science Advances, University of California, Santa Barbara, climate scientist Qinghua Dingand I show that atmospheric rivers have shifted about 6 to 10 degrees toward the two poles over the past four decades.
California relies on atmospheric rivers for up to 50% of its yearly rainfall. A series of winter atmospheric rivers there can bring enough rain and snow to end a drought, as parts of the region saw in 2023.
Atmospheric rivers occur all over the world, as this animation of global satellite data from February 2017 shows. NASA/Goddard Space Flight Center Scientific Visualization Studio
While atmospheric rivers share a similar origin – moisture supply from the tropics – atmospheric instability of the jet stream allows them to curve poleward in different ways. No two atmospheric rivers are exactly alike.
What particularly interests climate scientists, including us, is the collective behavior of atmospheric rivers. Atmospheric rivers are commonly seen in the extratropics, a region between the latitudes of 30 and 50 degrees in both hemispheres that includes most of the continental U.S., southern Australia and Chile.
Our study shows that atmospheric rivers have been shifting poleward over the past four decades. In both hemispheres, activity has increased along 50 degrees north and 50 degrees south, while it has decreased along 30 degrees north and 30 degrees south since 1979. In North America, that means more atmospheric rivers drenching British Columbia and Alaska.
The poleward movement of atmospheric rivers can be explained as a chain of interconnected processes.
During La Niña conditions, when sea surface temperatures cool in the eastern tropical Pacific, the Walker circulation – giant loops of air that affect precipitation as they rise and fall over different parts of the tropics – strengthens over the western Pacific. This stronger circulation causes the tropical rainfall belt to expand. The expanded tropical rainfall, combined with changes in atmospheric eddy patterns, results in high-pressure anomalies and wind patterns that steer atmospheric rivers farther poleward.
La Niña, with cooler water in the eastern Pacific, fades, and El Niño, with warmer water, starts to form in the tropical Pacific Ocean in 2023. NOAA Climate.gov
Conversely, during El Niño conditions, with warmer sea surface temperatures, the mechanism operates in the opposite direction, shifting atmospheric rivers so they don’t travel as far from the equator.
The shifts raise important questions about how climate models predict future changes in atmospheric rivers. Current models might underestimate natural variability, such as changes in the tropical Pacific, which can significantly affect atmospheric rivers. Understanding this connection can help forecasters make better predictions about future rainfall patterns and water availability.
Why does this poleward shift matter?
A shift in atmospheric rivers can have big effects on local climates.
In the subtropics, where atmospheric rivers are becoming less common, the result could be longer droughts and less water. Many areas, such as California and southern Brazil, depend on atmospheric rivers for rainfall to fill reservoirs and support farming. Without this moisture, these areas could face more water shortages, putting stress on communities, farms and ecosystems.
In higher latitudes, atmospheric rivers moving poleward could lead to more extreme rainfall, flooding and landslides in places such as the U.S. Pacific Northwest, Europe, and even in polar regions.
A satellite image on Feb. 20, 2017, shows an atmospheric river stretching from Hawaii to California, where it brought drenching rain. NASA/Earth Observatory/Jesse Allen
In the Arctic, more atmospheric rivers could speed up sea ice melting, adding to global warming and affecting animals that rely on the ice. An earlier study I was involved in found that the trend in summertime atmospheric river activity may contribute 36% of the increasing trend in summer moisture over the entire Arctic since 1979.
What it means for the future
So far, the shifts we have seen still mainly reflect changes due to natural processes, but human-induced global warming also plays a role. Global warming is expected to increase the overall frequency and intensity of atmospheric rivers because a warmer atmosphere can hold more moisture.
How that might change as the planet continues to warm is less clear. Predicting future changes remains uncertain due largely to the difficulty in predicting thenatural swings between El Niño and La Niña, which play an important role in atmospheric river shifts.
As the world gets warmer, atmospheric rivers – and the critical rains they bring – will keep changing course. We need to understand and adapt to these changes so communities can keep thriving in a changing climate.
Those last two paragraphs of the above article show the difficulty in coming up with clear predictions of the future. As was said: ‘How that might change as the planet continues to warm is less clear. Predicting future changes remains uncertain due largely to the difficulty in predicting thenatural swings between El Niño and La Niña, which play an important role in atmospheric river shifts.‘
For most dogs, their friend groups usually consist of a mix of humans and other dogs. But Lili, a 3-year-old dog who lives on a French Polynesian atoll called Fakarava, isn’t like most other dogs. She prefers friends who have gills and fins. In fact, her very best friend is a shark.
Ever since Lili’s mom, Emmanuelle Larchet, adopted Lili, she’s known that her dog has an affinity for all things aquatic. She started swimming in the lagoon near Larchet’s house when she was only a month old.
“She’s really a water dog,” Larchet told The Dodo.
There are around 100 sharks who live in this lagoon near Larchet’s house. So when Lili swims in the water there, she’s surrounded by them. While many dog parents would be terrified to see their dog swimming amongst sharks, Larchet knows that the sharks Lili swims with are nurse sharks, who are actually very docile creatures.
“We call them sea puppies because [they’re] like dogs, actually … They are very nice,” Larchet said.
Larchet likes to joke that when Lili swims around with her shark friends, it’s sea puppies meeting earth puppies.
Over the years Lili has been swimming in the lagoon, there’s one shark in particular she’s grown especially close with. His name is Sharky, and he and Lili visit each other almost every day. Larchet and Lili are able to recognize Sharky because he has a special marking on one of his fins.
Lili and Sharky like to explore their lagoon together. They enjoy splashing around in the warm, clear water.
“He comes to say hello every time she sees him,” Larchet said.
Even though Lili and Larchet are best friends themselves, Larchet is more than happy to share her Lili with Sharky. And even though Larchet watches Lili hang out with her shark friends all the time, it never gets old seeing them spend time together.
“[When] I see her swimming with Sharky, [I’m] so happy,” Larchet said.
The drawing depicts a turbaned cavalry soldier facing off against an English dragoon. It’s a bit trippy: The British soldier sits astride a carrot, and the turbaned soldier rides a grape. Both carrot and grape are fitted with horses’ heads and stick appendages.
‘The Battle of the Fruit and Vegetable Soldiers,’ a drawing on the back of a manuscript page from Charles Darwin’s ‘On the Origin of Species,’ attributed to Darwin’s young son Francis. Cambridge University Library, CC BY-ND
It’s thought to be the work of Francis Darwin, the seventh child of British naturalist Charles Darwin and his wife, Emma, and appears to have been made in 1857, when Frank would have been 10 or 11. And it’s drawn on the back of a page of a draft of “On the Origin of Species,” Darwin’s masterwork and the foundational text of evolutionary biology. The few sheets of the draft that survive are pages Darwin gave to his children to use for drawing paper.
Darwin’s biographers have long recognized that play was important in his personal and familial life. The Georgian manor in which he and Emma raised their 10 children was furnished with a rope swing hung over the first-floor landing and a portable wooden slide that could be laid over the main stairway. The gardens and surrounding countryside served as an open-air laboratory and playground.
Play also has a role in Darwin’s theory of natural selection. As I explain in my new book, “Kingdom of Play: What Ball-bouncing Octopuses, Belly-flopping Monkeys, and Mud-sliding Elephants Reveal about Life Itself,” there are many similarities – so many that if you could distill the processes of natural selection into a single behavior, that behavior would be play.
Through natural selection, the rock pocket mouse has evolved a coat color that hides it from predators in the desert Southwest.
In contrast to foraging and hunting – behaviors with clearly defined goals – play is likewise undirected. When a pony frolics in a field, a dog wrestles with a stick or chimpanzees chase each other, they act with no goal in mind.
Natural selection is utterly provisional: The evolution of any organism responds to whatever conditions are present at a given place and time. Likewise, animals at play are acting provisionally. They constantly adjust their movements in response to changes in circumstances. Playing squirrels, faced with obstacles such as falling branches or other squirrels, nimbly alter their tactics and routes.
Natural selection is open-ended. The forms of life are not fixed, but continually evolving. Play, too, is open-ended. Animals begin a play session with no plan of when to end it. Two dogs play-fighting, for instance, cease playing only when one is injured, exhausted or simply loses interest.
Keepers noticed that Shanthi, a 36-year-old elephant at the Smithsonian national zoo, liked to make noise with objects, so they gave her horns, harmonicas and other noisemakers.
Play is likewise profligate. It requires an animal to expend time and energy that perhaps would be better devoted to behaviors such as foraging and hunting that could aid survival.
And that profligacy is also advantageous. Animals forage and hunt in specific ways that don’t typically change. But an animal at play is far more likely to innovate – and some of its innovations may in time be adapted into new ways to forage and hunt.
Competing and cooperating
As Darwin first framed it, the “struggle for existence” was by and large a competition. But in the 1860s, Russian naturalist Pyotr Kropotkin’s observations of birds and fallow deer led him to conclude that many species were “the most numerous and the most prosperous” because natural selection also selects for cooperation.
Scientists confirmed Kroptokin’s hypothesis in the 20th century, discovering all manner of cooperation, not only between members of the same species but between members of different species. For example, clown fish are immune to anemone stings; they nestle in anemone tentacles for protection and, in return, keep the anemones free of parasites, provide nutrients and drive away predators.
Play likewise utilizes both competition and cooperation. Two dogs play-fighting are certainly competing, yet to sustain their play, they must cooperate. They often reverse roles: A dog with the advantage of position might suddenly surrender that advantage and roll over on its back. If one bites harder than intended, it is likely to retreat and perform a play bow – saying, in effect, “My bad. I hope we can keep playing.”
River otters at the Oregon Zoo repeatedly separate and reunite while playing in a tub of ice.
Natural selection and play also may both employ deception. From butterflies colored to resemble toxic species to wild cats that squeal like distressed baby monkeys, many organisms use mimicry to deceive their prey, predators and rivals. Play – specifically, play-fighting – similarly offers animals opportunities to learn about and practice deception.
And since natural selection shares so many features with play, we may with some justification maintain that life, in a most fundamental sense, is playful.