Category: Environment

Our Winter Solstice.

Is the moment of publishing this post.

I thought it would make a nice change to publish tomorrow’s post a little earlier than usual. To be precise to publish it on Dec. 22, at 04:48, Coordinated Universal Time (UTC). Or in our local Pacific Standard Time (PST) UTC-8 hrs or 20:48 Dec. 21., i.e. 20:48 on the evening of the 21st December. (I am seeing the exact time being declared as 04:48 or 04:49 UTC depending on what you read.)

Granted that the Northern Hemisphere tends to deliver the worst of the Winter weather after the shortest day, it still is good to know that for the next six months, the hours of daylight, in the Northern Hemisphere, will be increasing.

My inclination to write a post on the topic was greatly influenced by a most beautiful post over on Val Boyco’s blogsite. It was called And Winter Came. Here’s the video that Val included in her post.

Isn’t that a most beautiful few minutes!

Impossible to top that!

But I can continue including an informative item that was published over on Mother Nature News, and is republished here within the terms of MNN.

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8 things to know about the winter solstice

From when it happens to why, here’s your crash course on the shortest day of the year.

By: Melissa Breyer, December 18, 2015

Hello, winter. (Photo: psynovec/Shutterstock)

“A day without sunshine is like, you know, night,” quipped Steve Martin – and indeed, even a day with less sunshine can feel a bit dark. Our world depends on the light radiating from that big star we traipse around, and when it’s in short supply, we feel it. But if you count yourself amongst those who don’t love waking up before the sun rises and getting off work after it has set, things are about to lighten up. Hello, winter solstice!

Although winter is really just beginning, we can at least say goodbye to these short little days we’ve been suffering (and don’t let the door hit you on the way out). With that in mind, here’s a collection of curious facts to celebrate the long-awaited return to longer days.

1. There are actually two winter solstices every year 

It’s sometimes easy to be hemisphere-o-centric, but the other side of the planet gets a winter solstice too. With the planet’s orbit tilted on its axis, Earth’s hemispheres swap who gets direct sun over the course of a year. Even though the Northern Hemisphere is closer to the sun during the winter, it’s the tilt away from the sun that causes cold temperatures and less light — which is when the Southern Hemisphere is toasty. So while our winter solstice is on Dec. 21 or 22, the Southern Hemisphere celebrates the same on June 21 or 22.

Here’s how that looks from space (kind of):

2. The winter solstice happens in the blink of an eye 

Although the solstice is marked by a whole day on the calendar, it’s actually just the brief moment when the sun is exactly over the Tropic of Capricorn that the event occurs.

3. Which is why it happens on different days in the same year

What? Yes! In 2015, the solstice happens on Dec. 22, at 04:49 on the Coordinated Universal Time (UTC) time clock, the time standard that the world regulates its hours by. Which means any location that is at least five hours behind UTC should break out the party hats on Dec. 21. For example, in the United States the winter solstice happens on Dec. 21 at 11:49 p.m. Eastern Standard Time. The rest of the time zones can welcome longer days beginning on the 22nd.

4. It’s the first day of winter … or it’s not, depending on whom you ask

Meteorologists consider the first day of winter to be Dec. 1, but ask an astronomer — or just about anyone else — and they’ll likely answer that the winter solstice marks the start of the season. There are two ways to look at it: meteorological seasons and astronomical seasons. Meteorological seasons are based on the annual temperature cycle, explains NOAA, while astronomical seasons are based on the position of the Earth in relation to the sun.

5. It’s a time of gloriously long shadows

Shadows are at their playful best on the solstice. (Photo: Mike Page/flickr)

If you’re inclined to take pleasure in the little things, like shadows that seem cast from a funhouse mirror, then the winter solstice is the time for you. It’s now that the sun is at its lowest arc across the sky and thus, shadows from its light are at their longest. (Imagine a flashlight directly above your head and one hitting you from the side, and picture the respective shadows.) And in fact, your noontime shadow on the solstice is the longest it will be all year. Relish those long legs while you can.

6. Full solstice moons are rarer than blue ones

Since 1793, the full moon has only occurred on the winter solstice 10 times, according to the Farmer’s Almanac. The last one was in 2010, which was also a lunar eclipse! The next full moon on a winter solstice won’t be until 2094.

7. There’s a Christmas connection

Since Christ wasn’t issued a birth certificate, there’s no record of the date when he was supposed to have been born. Meanwhile, humans have been celebrating the winter solstice throughout history — the Romans had their feast of Saturnalia, early German and Nordic pagans had their yuletide celebrations. Even Stonehenge has connections to the solstice. But eventually Christian leaders, endeavoring to attract pagans to their faith, added Christian meaning to these traditional festivals. Many Christmas customs, like the Christmas tree, can be directly traced to solstice celebrations.

8. It’s a reminder to thank Copernicus

Will the real Saint Nick please step forward? (Photo: Wikimedia Commons)

The word “solstice” comes from the Latin solstitium, meaning “point at which the sun stands still.” Since when has the sun ever moved?! Of course, before Renaissance astronomer Nicolaus Copernicus (aka “super smartypants”) came up with the ‘ol heliocentric model, we all figured that everything revolved around the Earth, sun included. Our continued use of the word “solstice” is a beautiful reminder of just how far we’ve come and provides a nice opportunity to give a tip of the hat to great thinkers who challenged the status quo.

And now go have some hot cocoa. Happy winter!

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Only one way to close. That is with this picture of the sun perfectly aligned with the stones at Stonehenge in Wiltshire, UK at the moment of the Winter Solstice.

The December solstice happens at the same instant for all of us, everywhere on Earth. This year the solstice occurs on Tuesday December 22nd at 04:49 GMT (Universal time) with the sun rising over Stonehenge in Wiltshire at 08:04.

Stay safe and warm wherever you are.

The next post from Learning from Dogs will be published at 00:00 PST Wednesday, 23rd December.

First puppies born through IVF.

There’s more to this than initially meets the eye.

I’m back to another ScienceAlert article although this story has been widely reported including by our local newspaper, the Grants Pass Daily Courier. This is about in vitro fertilisation (IVF).

Now I am sure that I share with countless others a poor understanding of what IVF is. Here’s a Wikipedia extract:

In vitro fertilization or fertilisation (IVF) is a process by which an egg is fertilised by sperm outside the body: in vitro (“in glass”). The process involves monitoring and stimulating a woman’s ovulatory process, removing an ovum or ova (egg or eggs) from the woman’s ovaries and letting sperm fertilise them in a liquid in a laboratory. The fertilised egg (zygote) is cultured for 2–6 days in a growth medium and is then implanted in the same or another woman’s uterus, with the intention of establishing a successful pregnancy.

Obviously that applies to women.

A quick web search revealed that the IVF procedure is commonly used in livestock. Here’s a graphic example of that (literally):

IVFProcedure

All of which leads nicely in to the Science Alert story.

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These are the world’s first puppies born through IVF

Cutest science ever.

PETER DOCKRILL 11 DEC 2015

The world’s first litter of puppies born through in vitro fertilisation (IVF) represents the culmination of decades of research and has resulted in seven adorable pups called Cannon, Red, Green, Cornelia, Buddy, Kiwi and Ivy le Fleur.

But the achievement goes beyond almost intolerable cuteness. The researchers say successfully breeding puppies via IVF opens the door for saving endangered canid species and using gene-editing techniques to eradicate heritable diseases in dogs.

“Since the mid–1970s, people have been trying to do this in a dog and have been unsuccessful,” said Alex Travis, a reproductive biologist from Cornell University.

To develop the litter of pups, the researchers had to fertilise eggs from donor mothers with sperm from donor fathers in the lab, before transferring the embryos to a host female. 19 embryos were transferred to the host female in total, who gave birth to seven healthy pups.

Two of the pups came from a beagle mother donor and a cocker spaniel father donor, and the other five came from two pairings of beagle mothers and fathers.

The team had to overcome a number of challenges to make the process work. Picking the right time to collect mature eggs from the female oviduct proved difficult, as dogs’ reproductive cycles occur only twice per year typically. The researchers found delaying the egg collection by one day resulted in greater fertilisation than previous attempts.

An additional barrier was preparing the sperm for fertilisation, which is normally performed by the female tract. But the researchers found they could simulate these conditions by adding magnesium to the cell culture. “We made those two changes, and now we achieve success in fertilisation rates at 80 to 90 percent,” said Travis.

The researchers’ IVF process, described in PLOS One, will enable conservationists to store the semen and eggs of endangered canids and also help protect rare dog breeds.

“We can freeze and bank sperm, and use it for artificial insemination,” said Travis. “We can also freeze oocytes, but in the absence of in vitro fertilisation, we couldn’t use them. Now we can use this technique to conserve the genetics of endangered species.”

The IVF process should also lead to better genome-editing techniques in the future. This issue is particularly pertinent in light of the way that humans have bred dogs over many centuries. With the paired selection of mates for desired traits leading to detrimental genetic baggage due to inbreeding, this gives researchers a chance to eliminate diseases that certain breeds are now predisposed to.

“With a combination of gene-editing techniques and IVF, we can potentially prevent genetic disease before it starts,” said Travis.

We don’t always hear a lot about endangered canid species, but here are five candidates that this research will helpfully be able to help sooner rather than later.

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If you are like me and rarely follow the links in online stories then let me alert you to the last one. It’s an article in Scientific American that opens, thus:

The 5 Most Endangered Canine Species
By John R. Platt on May 9, 2013

Domesticated dogs are some of the most popular animals on the planet, but their cousins in the wild aren’t always as beloved. For thousands of years humans have persecuted wolves, jackals, dingoes, foxes and other members of the family Canidae, pushing many species into or close to extinction. Here are five of the most endangered canine species and subspecies, three of which only continue to exist because a few people and organizations have taken extraordinary efforts to save them.

I don’t have copyright permission to offer more. So all I will do is to list the names of those five most endangered species:

The Ethiopian wolf
The Mexican gray wolf
The red wolf
Darwin’s fox
Island fox

Do go here and read the full article. And let’s not forget that our lovely dogs are not the full canine story.

Picture parade one hundred and twenty-seven.

The most incredible and stunning photographs of ice!

Huge thanks to Dan Gomez for sending me these.

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More to come for a future Picture Parade!

You all take care in these days running up to the Christmas festivities.

Winter storms!

Apologies to you all!

Our internet service has been down, more or less the last several days.

It was restored some five minutes ago. Apparently down to the fact that our internet provider, Outreach Internet, had to purchase two snowmobiles to get access to the generators powering two of their masts!

The foul weather continues but fingers crossed so does our internet service.

Thus I hope Learning from Dogs returns to “normal service” starting with a new post at midnight PST tonight.

Picture parade one hundred and twenty-six

More appropriate images for the time of the year.

The previous set of images are here.

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You all stay warm and dry!

New findings in self-awareness.

For dogs!

We humans take self-awareness for granted. The key measure, as I understand it, is our ability to recognise ourselves, as in a mirror or photograph, for example.

I have more than once mentioned in posts in this place, that the evolutionary journey for us humans and our canine companions has resulted in the two species now sharing a number of psychological and physical ailments.

But what has been implicitly understood is that the one thing that dogs and us do not share is self-awareness. Hitherto, it has been believed that dogs do not recognise themselves in the mirror test.

All of which is an introduction to an item that was recently posted on the ScienceAlert website and was brought to my attention by dear friend Dan Gomez.

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Dogs show signs of self-consciousness in new ‘sniff test’
We knew it!

BEC CREW 10 DEC 2015

Self-awareness might seem like the most basic part of life to us humans, but it’s a surprisingly rare concept when it comes to other animals. While great apes, dolphins, orcas, rhesus macaques, Eurasian magpies, and a single Asiatic elephant have all passed the self-recognition test, everything from pandas and pigeons to sea lions, gorillas, and several species of monkey have failed to show signs of consciousness.

Dogs were also on that list of failures – until now. Traditionally, self-consciousness is evaluated via the ‘mirror test’. If an animal uses its own reflection to examine or touch a red mark that’s been applied to its body without its knowledge, scientists can confirm that they possess some sense of self. But what if the animal isn’t that visually oriented?

“I believed that because dogs are much less sensitive to visual stimuli with respect to what, for example, humans and many apes are, it is likely that the failure of this and of other species in the mirror test is mainly due to the sensory modality chosen by the investigator to test the self-awareness and not, necessarily, to the absence of this latter,” says evolutionary biologist Roberto Cazzolla Gatti from Tomsk State University in Russia.

Gatti was prompted into this line of thinking by the fact that in past mirror tests, dogs have shown no interest in looking at their reflection in the mirror, but they will go ahead and sniff the area and possibly even urinate around it. While this got them a big old “fail” in previous studies, Gatti thought the behaviour warranted a closer look.

Back in 2001, renowned animal behaviour expert, Marc Bekoff, investigated the ‘mirror sniffing’ phenomenon via an experiment dubbed the ‘yellow snow test’. Yep it’s exactly what it sounds like. Over a five-year period, Bekoff took his dog Jethro on walks during the winter months, and timed how long he would sniff clumps of snow soaked in his own or other dogs’ urine.

The AnimalWise blog explains:

“Bekoff would wait until Jethro or other known female and male dogs urinated on snow, and then scoop up the clump of yellow snow as soon as Jethro was elsewhere and did not see him pick it up or move it (Bekoff used clean gloves each time and took other precautions to minimise odour and visual cues).

Bekoff then moved the yellow snow varying distances down the path so that Jethro would run across the displaced urine: (i) within about 10 seconds, (ii) between 10 and 120 seconds later, or (iii) between 120 and 300 seconds later. After Jethro arrived, Bekoff recorded how long he sniffed at the yellow snow, whether he urinated over it using the typical male raised-leg posture, and whether urination immediately followed the sniffing (‘scent marking’).”

Not surprisingly, Jethro paid a lot less attention to his own urine than he did to that of other dogs, so Bekoff concluded that his pet had to have some sense of self to be able to distinguish between scents. But with a sample size of one, the experiment wasn’t exactly going to set the scientific community on fire.

Gatti decided to come up with something a little more convincing. Called the Sniff Test of Self-Recognition (STSR), the experiment involved collecting urine samples from four stray dogs and systematically exposing them to the scents. He repeated this four times a year at the beginning of every season.

“I placed within a fence five urine samples containing the scent of each of the four dogs and a ‘blank sample’, filled only with cotton wool odourless,” he says. “The containers were then opened and each dog was individually introduced to the inside of the cage and allowed to freely move for 5 minutes. The time taken by each dog to sniff each sample was recorded.”

Just like Jethro, each dog spent way more time smelling the urine samples of other dogs than their own, which supports the hypothesis that they know their own scent and aren’t that interested in it. The result was stronger the older the dog, which suggests that self-awareness develops with age.

It might seem obvious that dogs would know their own scent, but if you’ve ever seen a dog bark at its own reflection, or completely ignore it – totally unaware of its own appearance and movements – you can see the significance.

“I demonstrated that even when applying it to multiple individuals living in groups and with different ages and sexes, this test provides significant evidence of self-awareness in dogs and can play a crucial role in showing that this capacity is not a specific feature of only great apes, humans, and a few other animals, but it depends on the way in which researchers try to verify it,” says Gatti.

The findings are published in the journal Ethology, Ecology and Evolution.

Now, I know what you’re thinking: that sample size of four is pretty crap. And yep, it is, so we can’t really call this an official “pass” just yet. But the fact that we may well need to rethink the mirror test and figure out how to better align it with how certain species see the world is certainly worthy of a proper investigation. Certain behaviours such as empathy have been linked to self-awareness, and thanks to the ‘yawn test’, there’s evidence that dogs feel empathy towards their owners.

We’ll just have to wait and see if scientists are prepared to conduct a giant yellow snow test to put this conundrum to bed once and for all. In the meantime, here’s dolphins passing the mirror test adorably:

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Speaking of self-awareness, today, December 12th, is the centenary of the birth of Frank Sinatra.

Photo of Frank SINATRA, posed, c.early 1960s (Photo by GAB Archive/Redferns)

Picture parade one hundred and twenty-five.

The following seemed very appropriate for this time of the year!

(As seen on Mother Nature Network)

It may be made of snow, but it's just another toy ball to your dog. (Photo: b r/flickr) — It may be made of snow, but it’s just another toy ball to your dog. (Photo: b r/flickr)

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Wherever you are in the world; whatever the weather you and your dogs stay warm and happy!

Picture parade one hundred and twenty-four

More than a photograph, less than a film!

Enjoy these for today’s picture parade:

Published on Nov 6, 2015
Another try at a slow motion video of Abbey shaking the water off after a bath

Published on Apr 24, 2014
Stunning, Perfection, Breathtaking – just a few words that describe this 3 minute surfing clip that shows Ian Walsh catching huge waves and making it look effortless.

Well over two million viewings.

Music: Versailles
Warner // Chappell Production Music

Published on Oct 22, 2014

This is a clip from our movie “THE SECRET LIFE OF TREES”.
More on www.homan.pl

That homan.pl web link is well worth a visit – stunning stuff!

Finally, back to slow animal shakes! (And I must acknowledge Mother Nature News for the idea for today’s picture parade.)

Published on Mar 21, 2013
Why do wet furry mammals shake? Si and Sam give some of their favourite animals a shower to uncover the science behind the ‘wet dog shake’. Sam caught up with Andrew Dickerson from Georgia Institute of Technology to find out more about the science… we’ll have the full interview for you soon.

Food, agriculture, and our climate.

Locavore or vegetarian? What’s the best way to reduce climate impact of food?

With Thanksgiving Day just behind us and Christmas just around the corner, this is the season of feasting.

Just last Monday I published an essay written by George Monbiot, Pregnant Silence, that highlighted the impact on our climate of modern food production. Here are a couple of paragraphs from that essay:

Freshwater life is being wiped out across the world by farm manure. In England, as I reported last week, the system designed to protect us from the tide of crap has comprehensively broken down. Dead zones now extend from many coasts, as farm sewage erases ocean life across thousands of square kilometres.

Livestock farming causes around 14% of the world’s greenhouse gas emissions: slightly more than the output of the world’s cars, lorries, buses, trains, ships and planes. If you eat soya, your emissions per unit of protein are 20 times lower than eating pork or chicken, and 150 times lower than eating beef.

Thus it seemed both timely and appropriate to republish a further essay on the topic. This one published in The Conversation by Elliott Campbell, who is Associate Professor, Environmental Engineering, at the University of California. It is republished here under the terms of essays published in The Conversation.

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Locavore or vegetarian? What’s the best way to reduce climate impact of food?

November 25, 2015

Elliott Campbell

This year’s Thanksgiving feast falls only a few days before the start of the global climate summit in Paris. Although the connections are not always obvious, the topic of food – and what you choose to eat – has a lot to do with climate change.

Our global agriculture system puts food on the table but it also puts greenhouse gases (GHG) in the air, which represent a huge portion of global emissions. GHG emissions come directly from farms such as methane from cows and nitrous oxide from fertilized fields, while other emissions come from the industries that support agriculture, such as fertilizer factories that consume fossil fuels.

Still other emissions come from natural lands, which have massive stocks of natural carbon stored in plants and soils. When natural lands are cleared to make room for more food production, the carbon in those natural pools is emitted to the atmosphere as carbon dioxide.

Adding all these emissions together makes agriculture responsible for between roughly one fifth and one third of all global anthropogenic, or man-made, greenhouse gas emissions.

How can these emissions be reduced? My own research through the University of California Global Food Initiative has focused on evaluating a wide range of factors from biofuels to local food systems.

Undoubtedly, broad emissions reductions must come from political action and industry commitments. Nevertheless, an enlightened consumer can also help achieve meaningful reductions in GHG emissions, particularly for the case of food. The trick is to understanding what food means for your personal carbon footprint and how to effectively shrink this footprint.

On par with electricity

Zooming in from the global picture on emissions to a single home reveals how important our personal food choices are for climate change. You can use carbon footprint calculators, such as the University of California CoolClimate Tool, to get an idea of how important food is in relation to choices we make about commuting, air travel, home energy use, and consumption of other goods and services.

For the average U.S. household, food consumption will be responsible for about the same GHG emissions as home electricity consumption for the average US household.

Measuring the greenhouse gas impact of different foods is complex but in general, it’s commonly agreed that plant-based diets have a lower carbon footprint. davidwoliver/flickr, CC BY-NC

That’s a significant portion of an individual’s GHG footprint but it could be seen as a blessing in disguise. While you may be stuck with your home or your vehicle for some time and their associated GHG emissions, food is something we purchase with great frequency. And every trip to the grocery store or farmer’s market is another opportunity for an action that has a significant and lasting impact on our climate.

Making concrete decisions, though, is not always straight-forward. Many consumers are faced with a perplexing array of options from organic to conventional foods, supermarkets to farmers markets, and genetically modified organisms to more traditional varieties.

And in truth, the carbon footprint of many food options is disputed in the scientific literature. Despite the need for more research, there appears to be a very clear advantage for individuals to chose a more plant-based diet. A meat-intensive diet has more than twice the emissions of a vegan diet. Reducing the quantity of meat (particularly red meat) and dairy on the table can go a long way to reducing the carbon footprint of your food.

Food miles and water recycling

Local food systems are popularly thought to reduce GHG emissions through decreased food transport or food miles. But in many cases food miles turn out to be a meaningful but small piece of the overall GHG emissions from food.

For example, a broad analysis of the US food supply suggests that food miles may be responsible for less than 10% of the GHG emissions associated with food. This general trend suggests that where you get your food from is much less important than first-order issues, such as shifting to a more plant-based diet.

A little-appreciated way of reducing the carbon footprint of food is to recycle nearby water rather than pump it long distances. The Pajaro Valley Water Management Agency (PVWMA) Water Resources Center in California sanitizes wastewater for direct use or blending with ground (well) water. US Department of Agriculture, CC BY

Where, then, does this leave a rapidly emerging local food movement?

For starters, there are some cases where food miles have greater importance. For example, food miles can play a big part in the carbon footprint of foods when airplanes or refrigeration are required during transport.

There is, however, untapped potential for locally produced food to deliver carbon savings around water and fertilizers.

When water is pumped long distances, it can add to food’s carbon footprint. Re-use of purified urban wastewater for irrigating crops represents one strategy for addressing this challenge but is only economically and environmentally feasible when food production is in close proximity to cities.

Using fossil fuels to produce fertilizers, such as ammonia, can also be a big piece of the carbon footprint of food. Nutrients in reclaimed wastewater and urban compost may provide a low-carbon alternative to fossil fuel-based fertilizers. But similar to water re-use, reusing nutrients is most easily done when there is a short distance between food production and consumption.

To be sure, buying local food doesn’t imply that food or nutrient recycling has happened. But developing local food systems could certainly be a first step towards exploring how to close the water and nutrient loop.

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I am sure many, as with me, tend not to follow through on all the links in an online essay. But there was one that really caught my eye. It was the CoolClimate Calculator on the Berkeley Edu website. It allows one to fill in a number of figures in terms of living, travel, food and more, and determine one’s total tons CO2/year emitted and how that compares with other people in your neighbourhood. Unfortunately, it only calculates CO2/year for US locations. Does anyone know of similar calculators online in, say, the United Kingdom? Would love to know.

What nature makes up!

A suitable postscript to yesterday’s post.

Yesterday, I wrote a post under the title of You couldn’t make it up! It featured a recent essay Pregnant Silence from George Monbiot about the consequences and implications of the widespread consumption of meat and dairy products.

Now look at this example of what nature does make up.

A Sunset with Searchlights

You know those glorious fingers of sunlight that sometimes burst out from behind clouds? They’re called ‘crepuscular rays’, they form when light and shadow are rendered visible by haze in the atmosphere and these photographed by Alli Bush over Fort Collins, Colorado, US, are the Cloud of the Month for November.

The haze giving rise to crepuscular rays can be due to the air being filled with fine particles such as sand, dust or pollen. Or it can result from a delicate mist of water droplets – plentiful enough to scatter the sunlight but too scarce to show up as a cloud. The scattering is the important bit. Since we only see light that shines directly into our eyes, rays of sunlight shining in other directions are not visible unless they encounter something that scatters light towards us. Think of shining a torch beam on a clear night. The light only appears where it strikes a surface such as the ground. But on a foggy night, the full torch beam shows up because some light is also scattered towards us by the droplets of fog in the air it passes through. This is why a hazy sky renders rays of sunlight visible.

The other requisite for crepuscular rays besides haze is something to cast the shadows. Most commonly it is a cloud blocking the sunlight that creates the regions of light and shadow we see in the sky. But the crepuscular rays in Alli’s photograph are cast not by clouds but by the peaks of the Rocky Mountains. The rays fan outwards because they are coming towards the camera. In fact, the Sun’s rays are actually pretty much parallel by the time they reach Earth. They only appear to spread out like this because of the effect of perspective. It is just like looking down the length of train tracks. Even though they are parallel, they appear to spread outwards the nearer they are. Only when the sun is high in the sky so that its rays are pointing more directly downwards do crespuscular rays look parallel.

Crepuscular rays over Fort Collins, Colorado, US © Alli Bush.

The photograph comes from the website of The Cloud Appreciation Society of which I am a lowly member. Thus it was that in my in-box yesterday was their latest newsletter. In that newsletter there was the following stunning film, described thus:

This month, we were sent an amazing film of storms over Arizona, US. It was made by Davo Laninga, Cloud Appreciation Society Member No 1,095. You can learn a lot about how storms develop by watching time-lapse videos. Well done, Davo, for this stunning example, showing the monumental power that drives our atmosphere.

Do drop in to Dave’s website and admire his incredible photographs and videos.

And enjoy this:

Puts things back into perspective, doesn’t it!

8 things to know about the winter solstice

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These are the world’s first puppies born through IVF

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Dogs show signs of self-consciousness in new ‘sniff test’ We knew it!

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Locavore or vegetarian? What’s the best way to reduce climate impact of food?

On par with electricity

Food miles and water recycling

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Dogs show signs of self-consciousness in new ‘sniff test’
We knew it!