The 2015 "Slushy" Waves of New England

It’s too bad that seawater is salty, because with a bit of sweet flavouring, everyone would have had access to unlimited slushy “Slurpee” a year ago, courtesy of Mother Nature!

Video Source: “Giant Frozen Waves Nantucket Beach” Uploaded by Galaxy 11

The United States spent much of February of last year in the frigid grips of a record-breaking icy winter. Yet, in addition to the usual suspects, which include deep snow and biting winds, the cold would seem to have even won over the briny seawater of the north Atlantic Ocean. This video shows a series of images of ocean waves breaking on the shores of Nantucket in New England (northeast USA), only, there seems to be something distinctly different about these waves!

The photographer, Jonathan Nimerfroh, is an avid surfing enthusiast and on a trip to the beach, he noticed something odd about the horizon. As it turns out, the temperatures are so low in the area the water has begun to freeze and so, what we are looking at are giant slushy waves! These icy waves have also been aptly called “Slurpee waves”

The maximum temperature on the day these pictures were taken was at a teeth-chattering -7 degrees celsius (17 degrees Fahrenheit).

What’s truly amazing about this is that salt is known to lower the freezing point of water to well below zero degrees celsius. This is precisely why we throw salt over our driveways to prevent them from icing up. The fact that even the salty seawater in northeast United States began to freeze is testament to the uncharacteristically cold winter they had last year.

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Enlightening! How Lightning is Made

Lightning thunderstorm picture 

What’s more than ten kilometres (6 miles) long, five times hotter than the surface of an average star and packs in more strokes per second than an over-zealous teenage boy who’s just discovered the joy of internet porn?

Yeah, I know. The picture kind of gives it away doesn’t it?

I have had a complete love affair with thunderstorms for as long as I can remember. I think they are the most awe-inspiring and yet paradoxical demonstration of nature’s prodigious temper and seductive grace. In the space of an hour, the sky can go from an azure blue to the colour of dark slate as giant cumulonimbus clouds broil and swell with latent energy.

Thunderstorms generate all kinds of severe weather: torrential downpours, vicious winds, hail, microbursts and even tornadoes. But they indirectly owe their very name to the one weather feature that claims the lives of, on average, 55 people every year in the United States: lightning!

Shocking Statistics

NASA_Lightning_Climatology

Source: Global distribution of lightning April 1995 – February 2003 from the combined observations of the NASA OTD (4/95-3/00) and LIS (1/98-2/03) instruments.

Approximately 8 million bolts of lightning strike the Earth every single day, starting 10,000 forest fires annually. In the United States, over 300,000 insurance claims are made against lightning damage every year and the bill for this damage is a staggering $400,000,000.

Yes. Thunderstorms are seriously dangerous systems. I shouldn’t have to tell you that and yet countless golfers are killed by lightning every year. Could there be anything less intelligent than standing in the middle of a wide open space during a thunderstorm with a metal rod in your hand pointed at the sky? With five billion joules of energy surging through a single lightning bolt – enough energy to illuminate a 100 watt bulb for three months – you are picking a fight you simply cannot win.

Against all logic, according to the U.S. National Weather Service, lightning STILL kills more people than tornadoes AND hurricanes combined. What is this madness?

It’s Electricity! 

Lightning thunderstorm picture 2

Thunderstorms are extremely busy weather systems. Within a storm cell, legions of water vapour particles are whipped, flung and tumbled around by complex air circulations. Storms themselves are powered by strong updrafts of hot, moist air. This air cools and condenses as it rises through the heights of the lower atmosphere, becoming dense. It consequently loses its upward momentum and sinks and spills out of the rear of the thunderstorm (check out the diagram below).

thunderstorm diagram

Photo Credit: “Thunderstorm formation” by NOAA T-storm-mature-stage.jpg. Licensed under Public Domain via Wikimedia Commons

Together, these motions form a continuous cycle of updrafts and downdrafts, which provides the storm system the energy it needs to electrocute golfers, whip cows into the air and blow Dorothy and her dog, Toto, into a parallel reality.

How does this explain what lightning is? Well, it brings us a lot closer to understanding cloud polarization. OMG. What does that mean?

Clouds Can be Bi-Polar Too

Just like batteries, molecules and certain members of your family, clouds too can become bi-polar. Within a thunderstorm, legions of water vapour particles get swirled around violently by the turbulent air circulations. But there are two predominant movements of air in a single cell storm system: hot moist air going up and colder drier air going down.

The water vapour particles being swept up into the cloud smash into those going down and these collisions, while totally invisible to us, are violent enough to cause the descending water particles to literally tear electrons off of the ascending water particles. Electrons are negative. So you see there is a gradual separation of charge within a thundercloud as the descending water particles become negatively charged and the rising water particles (having had an electron or two pilfered from their orbitals) become positively charged.

cloud polarisation thunderstorm

Credit: Earth Science Australia

As a result of particle motions within a thunderstorm, the lower cloud regions become negatively charged and the upper cloud regions positively charged. A positive charge is induced in the ground immediately below the thunderstorm in response to storm’s electric field.

The story doesn’t end here: the polarization of the thundercloud has an effect on its environment, namely, the surface of the Earth and the various objects on it. An electrical field swells outwards from the cloud, caressing the electrons belonging to Earth’s atoms, seducing them into moving. Those who studied physics will remember, electron movement = charge.

The presence of such a massive reservoir of negative charge immediately above the Earth’s surface repels its negatively charged electrons (like repels like), causing an opposing positive charge to build up. In other words, trees, poles, buildings and your head actually develop a static positive charge in the seconds prior to lightning strike. This is probably why people who have been struck by lightning and have lived to tell the tale say that they felt their hair stand on end just before they become a living conductor for 1,000,000,000 volts of electricity.

Zap!

Lightning thunderstorm picture 4

At some critical juncture, nature notices the thunderstorm’s complete disregard for her love of equilibrium and so a raging streak of electricity discharges between the negative and positively-charged cloud regions. Or the negatively charged lower cloud regions and the positively charged ground immediately below it. And ZAP! You get lightning!

I can feel the cogs of your mind over-heating. So, if you aren’t quite happy with this explanation, then watch the movie Thor. While it doesn’t provide any scientific explanation on lightning genesis whatsoever, Chris Hemsworth is so beautiful you will forget your intellectual torment immediately *swoon*

Guys… you can enjoy watching Natalie Portman at her career low. In a lab coat.

I know I did.

sexy natalie-portman-celebrity

Thunder, Contrary to Kindergarten Mythology, is Not God’s Fart

In spite of my illuminating explanations above – coupled with your homework to watch Thor – the exact physics of lightning generation are not entirely understood. Thunder, on the other hand, is and its explanation makes for a very interesting story. You may want to remember this so you can impress a future date with it…

When lightning tears out of a cloud, the air in the discharge channel heats up from ambient air temperature to a toasty 28,000°C or 50,000°F. That’s approximately five times hotter than the surface of our Sun. And all of this happens in as little as 90 microseconds. I know, right? A yawning chasm of a time denomination.

The problem is, you can’t heat anything up from 10°C to 28,000°C in this short amount of time without some kind of catastrophic consequence. So when lightning shows the ill social etiquette of doing so, the air expands violently, generating a shockwave that explodes outwards from the discharge channel. This shockwave travels faster than the speed of sound – it’s supersonic – so we can’t actually hear it. Dogs probably could, but you’ll have to ask one to be certain.

With distance from the discharge channel, this shockwave slows down and as it does it falls within our audio range. That’s when we hear thunder. I have heard that if you stand close enough to lightning you won’t actually hear it, because the shockwave is supersonic. While this makes sense in theory, human trials are pending. It also explains why, when a storm is very close, the lightning makes a sharp cracking explosive sound while, when further away, you hear the thunder as a low sexy rumble.

Lightning thunderstorm picture 5

Class Dismissed: Your Take-Home Message

More people die of lightning injuries in Florida than anywhere else in America and perhaps even the world. While I’m aware that they have an amazing water world playground at their feet, they also have the highest lightning strike density in the entirety of the United States. Perhaps y’all should bear that in mind the next time you go wind surfing in an electrical storm.

Regardless of where you live, however, if you value your life then don’t swim, don’t bath, don’t chat on a land line, don’t play golf, don’t stand under a tree and don’t go running around like Julie Andrews in a thunderstorm. Otherwise, it won’t just be music the hills are alive with.

Oh, and enjoy the show! Isn’t nature spectacular?

Lightning thunderstorm picture 3

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Somewhere Over the Rainbow, Photons Fly!

Beautiful rainbow Grand Canyon

Image Source: “Rainbow Ignites” over Grand Canyon, uploaded by Cathy Smart to travel.nationalgeographic.com

Rainbows have enchanted humankind since our very beginnings, leading to the spinning of countless myths and legends about why and what they are. Just about every ancient civilization, culture and religion has its unique explanation of rainbows; all of them creative, but absolutely NONE of them correct. There is no pot of gold.

Aside from the fact that they look like a hippy has barfed across the sky, rainbows have quite a fascinating backstory involving the physics of light, which really isn’t all that complicated! In this blog, we’ll be taking a look at the physical laws and facts that give rise to some spectacular atmospheric masterpieces and a sky that would put a tie-dye T-shirt convention to shame.

The first ingredient on our palette is solar radiation…

You Need Sunshine, On a Cloudy Day!

One does not simply meme

Sunshine. It’s a simple concept: light from the sun. But one does not simply have interminable nuclear reactions without generating a spectrum of electromagnetic radiation. Our sun is a star and in keeping with the personality of stars, things are positively nuclear beneath its photosphere. These nuclear fusion reactions release a broad range of radiation types (see diagram below), from low energy, long wavelength infrared radiation (left) to the high energy, short wavelength Gamma radiation (right).

the_electromagnetic_spectrum

Image Source: The Electromagnetic Spectrum – faculty.olympic.edu

Slap bang in the middle of the electromagnetic spectrum is visible light, which only accounts for a narrow portion of the total energy generated by our sun day-after-day. This visible light pours out into space faster than Kris Jenner can say to Bruce “You’re becoming a what!?” covering the vast distance between the Sun and Earth in just 8 minutes and 20 seconds. It then smacks into our atmosphere and all its constituent gas and water vapor molecules. The photons (particles of light) that manage to escape atmospheric collision end their journey at the Earth’s surface, which is what brings warmth to our lives and color to our environment.

Snow White Light and the Seven Composite Colors

As I explained in the blog The Sky Is Only Sometimes Blue, visible (white) light is composed of seven different colors. Each of these colors has a different wavelength and ranges from the lower frequency, longer wavelength color red to the higher frequency, shorter wavelength color violet.

When visible light from the sun strikes a white surface, all of its seven dwarfs, I mean constituent colors get scattered in every direction, which is why we view the object as Snow White, I mean white. If that object is black, however, all of those seven colors become absorbed by the object, which is why you can cook an egg on the dashboard of your black Merc after leaving it in the sun for an hour.

visible light spectrum rainbow

Image Source: The Visible Light Spectrum – CultureLab/LabCulture at http://www.viralprojects.com

What about colorful objects?

Violet surfaces, like your gay best friend’s curtains, selectively scatter light with a wavelength of around 400 nanometers and absorb the rest. As such, you perceive the color violet (and bad taste) when you look at them.

Blue surfaces, like your lover’s eyes, selectively scatter light with a wavelength of around 450 nanometers. As such, you perceive the color blue and experience inappropriate clenchings in the nethers.

MIRRORS, interestingly enough, reflect all the seven colors of incoming visible light, but instead of scattering them in random directions, they reflect them at precisely the same angle as they arrived at and so the integrity of the image is preserved.

WHAT does this have to do with rainbows?

This discussion is intended to help you understand and appreciate the nature of visible light and the fact that it’s composed of different colors, which are capable of acting independently of each other due to their different wavelengths.

Now it’s when visible light strikes water droplets in our atmosphere that the real magic can begin to happen, potentially making it look like a unicorn wiped its butt on the horizon…

Prism (Not a Katy Perry Album)

Prism rainbow

Image Source: All The Pretty Colors – SeeMore Sights, http://www.seemoresights.net

So far, we’ve spoken about light as though it travels in a straight line, which is typically what it does between bouncing off of and being scattered by objects. However, this isn’t the case when it travels through water. When visible light travels from one medium to another – from air into the water – its pathway becomes slightly bent in a process termed “refraction.” This explains why objects under water look so strange: the light that enables us to perceive them is being refracted or bent and this makes your toes (or whatever body part you happen to be scrutinizing) look bigger and closer to you than they really are.

When sunlight passes through a water droplet, it deviates slightly from its incoming direction, because it’s refracted (see diagram below). A portion of this light is then reflected off the far surface of the raindrop. If this angle is at 40° – 42° to the original direction of incoming sunlight, we get a rainbow!

how rainbows are formed

Image Source: What Causes a Rainbow? NASA/NOAA – scijinks.jpl.nasa.gov

So you see, rain droplets not only refract the sunlight that passes through them, they also act as prisms. The reason this process results in a rainbow is because the seven constituent colors of visible sunlight become refracted to different degrees: the shortest wavelength light (violet) becomes refracted the most and so it’s bent the most. The largest wavelength light (red) becomes refracted the least and so it’s bent the least. As such, when white light passes through a water droplet, it becomes split into its seven different personalities, from violet, blue and green to yellow, orange and red!

This is beautifully captured in the following 40-second video:

Video Source: “Light Split into Colors by a Prism” Uploaded by MadDogScience in YouTube channel http://www.youtube.com/watch?v=hLFcf58qD4w

A Rainbow Is Made!

We can now understand how white visible light, upon passing through water droplets suspended in the atmosphere, is split into its seven constituent colors. The final piece of the puzzle is looking at this process on the large scale. There are billions of water droplets in clouds or mist and each one disperses and refracts the sunlight that hits it. The overall result is a vast display of color in a circular or semicircular arc. Obviously, to us here on Earth, most rainbows would appear to be semi-circular, because the ground gets in the way of us seeing the other half. However, viewed from the air or from the following rare perspective at the top of Zambia’s Victoria Falls, we can see the full glorious monty:

Rainbow, Victoria Falls, Zambia - Aug 2012

Image Source: Circle Rainbow Over Victoria Falls, Zambia – Aug 2012 by Nicole Cambré/REX (2105841a): FULL WORDS LINK: http://www.rexfeatures.com/nanolink/ju4n

What I haven’t mentioned yet is that perspective plays a major role in our ability to visually enjoy rainbows. The sun has to be behind you and the angle of dispersion – the angle between the incoming sunlight and the direction the refracted light is exiting the raindrop – has to be between 40° and 42°.

Beautiful rainbow pictures

Image Source: Rainbow Over Lake Ontario, uploaded by Melagoo on Weather Underground, http://www.wunderground.com.

Class Dismissed: Your Take-Home Message

Rainbows have this wonderful effect on people: they make us look. They compel us to forget for just a few seconds everything it is we are thinking/worrying/stressing about and look up to the sky and admire. Really, all a rainbow is is water droplets playing with the paths and emotions of sunlight… but they are beautiful and a reminder that God – or whatever deity is or isn’t up there – is in fact a fan of gay people.

lgbt gay rainbow flag

Image Source: http://www.telegraph.co.uk

Copyright © Thea Beckman 2015