Gird Your Loins, It's El Niño Time!

Paris Weather funny

It took two long haul flights, six plastic wrapped airline meals, three movies, two cantankerous airhostesses and a dangerous brush with halitosis for me to learn about the latest crisis throwing a spanner in the works of the mankind’s (mostly shoddy) attempts to run things smoothly on planet Earth.

I’m talking, of course, about El Niño.

I had to come to Los Angeles to learn that we’re actually teetering on the edge of what the western media is referring to as a “monster El Niño event” and by the time I publish this, we may very well have taken the dive. Where I come from – South Africa – the media and moreover the government pay scant attention to weather and climate issues. This is extremely ironic considering our economy is based on primary industry and that El Niño years are linked with drought in Southern African’s interior. So, in keeping with this relationship, we’re currently facing critical drought conditions for which the government has done nothing to prepare.

Alas! Here in South Africa, the government is far too distracted by President Zuma’s antics in and out of parliament and the country’s courtrooms to worry about the fact that our crops are about to shrivel up faster than Zuma’s manhood when it was explained to him that showering after intercourse does not in fact prevent the transmission of HIV. And unfortunately, they would also rather spend taxpayers’ money on private jets, fancy cars and extravagant lifestyles for its unprecedented number of officials than on research into, and mitigation for climate change and global climate phenomena like El Niño. If you were a selfish, uneducated pack of pricks, wouldn’t you too?

Anyway, that is where my political rant ends. The point is this: I only recently learned that the planet is facing the meanest El Niño event since 1997 and is set to become one of the three strongest on record, like, ever. It’s already causing all kinds of interesting weather anomalies across the world, especially in the United States. So, it’s time for a new blog in which we’ll meet “the boy” wreaking an incredible amount of wanton mischief on our biology, biomes and backyards.

Joffrey Game of Thrones
Vainglorious little swine…

Who Is This “Boy” And Why Does He Mischief Thusly?

El Niño refers to the periodic, unusual warming of the ocean waters of the central and eastern equatorial Pacific and it’s named “the boy” in Spanish after the baby Jesus, since it typically occurs around Christmas time. Understanding why El Niño has such extensive impacts upon weather requires us to take a closer look at a very important variable (sea surface temperature) as it usually is versus what it becomes when El Niño buggers around with ocean and atmospheric circulations. And so, the instigator of it all – the key player I need to introduce you to first is…

The Easterly Trade Winds!

Easterly trade wind diagram

 Image Source: mrspruillscience.weebly.com

Over the tropical Pacific Ocean, in other words around the equator, the trade winds blow roughly from east to west (see diagram above). Now, wind may seem like nothing more than moving air until your house gets relocated by a tornado; only then do you realize it’s a force to be reckoned with! So, the effects the northeast and southeast trade winds have on the ocean surface in the equatorial Pacific are quite significant.

The easterlies exert a force on the warm surface water, pushing it and causing it to pile up in the west, so much so that there is actually a 500-milimetre difference in sea surface height between Indonesia (west) and Ecuador (east)! This does a few things:

  1. With the warm surface waters being piled up in the west, an 8°C temperature difference is created between the eastern and western equatorial Pacific, with the west being beautifully toasty. A warm ocean surface makes for a sexy, moist atmosphere and the result is a lot of rainfall. This is why Indonesia is beautifully lush.
  1. On the other side of the Pacific, the wind pushing the surface waters away from the South American coast causes cold water from depth to rise to the surface (upwell), thereby leaving the ocean here chilly enough to embarrass you if you were dude wearing a speedo swimsuit. And, of course, the air overlying a cold ocean is typically dry and promotes little rainfall.

Ocean upwelling is a really important process, so it deserves a little conversation before we continue. When ocean creatures and critters die, their bodies sink, making the waters at depth wonderfully fertile. The upwelling of this water to the surface brings all this organic matter into the glorious sunshine and this leads to a surge in primary productivity. Of course, with great volumes of delicious algae, plankton and other tiny sea squishies available, every critter in the food chain is given the energy influx it needs to prosper, which essentially means lots of rodgering, lots of babies and lots of biological success. It also means lots of sushi for us.

Swarm of krill
Oh look! Krill!

Photo Source: http://www.krillfacts.org

So, we have a warm western equatorial Pacific with a rainy atmosphere and a cool eastern equatorial Pacific and a dry atmosphere. That’s the way it USUALLY is with the northeast and southeast trade winds happily blowing.

However: every two to seven years – and there doesn’t appear to be any strict rhyme or reason as to the frequency of this – the normally healthy trade winds stagger and weaken and you would scarcely BELIEVE the cluster f**k of consequences that follow.

 A Specific Account of the Cluster of F**ks That Follow

With the easterly trade winds fizzling out, all the beautifully warm water that is usually swept to the west is allowed to slough back into the east. This causes a tongue of warm water to spread out from the western coastline of North America (see diagrams below).

El Nino Pacific SST
This diagram shows us December sea surface temperatures (SST) as they normally are over the Pacific Ocean (first image), as El Niño is setting in (middle image) and during the event’s crescendo (final image). You can really see the distribution of heat moving away from the west and becoming concentrated over the eastern equatorial Pacific.

 Image Source: El Niño Southern Oscillation, http://www.ic.ucsc.edu

If this picture series doesn’t tickle your fancy, the following video will…

Video Source: “Amazing New El Niño Animation Reveals Shocking New Details” Uploaded by ShantiUniverse on Youtube channel https://www.youtube.com/watch?v=pc2wYXK3qRk

A key point you must remember is that the ocean and atmosphere seldom, if ever, act independently of each other. One minor change in sea surface temperature can cause the atmosphere to overreact like your girlfriend approximately one week before Aunt Flo arrives for her monthly visit. A warm sea surface leads to greater evaporation, a more humid atmosphere and therefore more rainfall.

So, with ocean heat draining from the usually wet western Pacific, the region is typically left in drought while the east, which is usually dry, becomes unusually wet. On the ground, Indonesia and Australia can experiencing drought and, in Australia’s case, a much greater risk of catastrophic bush fire. On the eastern side of the Pacific, where the ocean has become anomalously warm, unusually heavy rainfall can lead to flooding with the risk being greatest to the southern states of America and Peru.

El Nino flooding in Peru
The El Niño event of 2010 was believed to drive the devastating floods that affected Peru.

 Image Source: http://news.sciencemag.org/climate/2014/08/ancient-piles-clams-reveal-peek-el-ni-os-past

The weakening of the trade winds also negatively affects the upwelling that usually occurs off the western coast of South America and by throttling the source of nutrients these marine ecosystems rely on, organisms of all echelons in the food chain take a major blow. Less importantly (in the grand scheme of things – don’t tell any local fisherman I’m saying this) our fishing industries also suffer. That’s right: less sushi.

Leave Britney alone
Leave sushi alone!

If you thought that’s where it ends, think again. El Niño’s impacts spread further than a desperate housewife’s legs. The accumulation of vast reservoirs of heat energy at the eastern periphery of the equatorial Pacific drive significant changes in global atmospheric circulation, which essentially means that no matter where in the world you live, you can possibly expect the next few months’ of weather to be, uh… interesting.

Crappy Weather Coming To a Neighborhood Near You

Global warming disaster

Air in the atmosphere is constantly on the move and it’s thanks to our major global atmospheric circulations that all the crap going down in the Pacific is felt in varying degrees across the globe.  Here are some cherry-picked samples of other global consequences:

El Niño events are linked with wilder hurricane seasons in the Pacific. This is terrible news for the Philippines, which is already one of the most disaster-struck countries in the world. According to Colorado State University, there have been 21 Category 4 and above (read: holy crap that’s big!) hurricanes in the north Pacific this year alone. This total has obliterated the previous record of 17, which was set during the monster El Niño of 1997. The good news for Florida and southern Texas is that hurricanes in the Atlantic tend to stay home and pursue their hobbies during El Niño months.

Africa may be half the planet away, but the continent has a decent sized serving of interesting weather to expect. Southern Africa is currently in the throes of severe drought, while several East and North African nations are being pelted by heavy rainfall. I mean, can’t we ever just get the RIGHT amount of rain?? Why must it be one extreme or the other?

And, of course, we can’t leave out the main character in this story of wanton weather: MURICA! The following prediction maps for temperature and rainfall have been issued by the National Ocean and Atmospheric Administration (NOAA) on their amazing website, which you can view at www.climate.gov.

DJF_Temp_outlooks_2015 El Nino
Temperature forecast for the period December 2015 to February 2016

 What we can tell from this map (aside from the fact that NOAA doesn’t give a hoot about Canada) is that there is a good chance of temperatures being hotter than usual in much of Alaska, Washington and the northern U.S. with dark red indicating a 70%+ probability of hotter than usual conditions. Texas and much of the southern states, on the other hand, may actually have to invest in a sweater or two. 

Class Dismissed: Your Take-Home Message
Sexy blonde walking away from explosion
Is it the end of the world? Should you start looting your neighborhood grocery store and stocking up on bottled water and canned beans? No. Well, no to the first one: no harm ever came from having an extra can of baked beans, but you may want to prepare your home if you’re in an area that’s at risk of flood or drought. The question on the media’s lips is: is this particularly strong El Niño event proof of climate change and the severe weather we can come to expect from a globally warmer atmospheric environment?

Until we can say what causes the easterly trade winds to die down every two to seven years, we won’t be able to define the relationship between El Niño events and global warming. What is pretty evident – and has been talked about by climate scientists for years – is that a warmer atmosphere contains more moisture (due to greater evaporation) and more energy and is therefore more prone to the development of severe storms.

Your take-home message is this: The atmosphere is like the movie Cloud Atlas: It’s complicated and no matter how closely you study it, you still wonder what the f**k happened in the end. Just remember that the next time you hurl insults at the weatherman for getting the forecast wrong!

Funny weather man meme

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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

Goodness, Gracious Great Balls of Ice! The Story of Hail

Large hailstone picture

Source: A massive 2.4 inch aggregate hailstone (about 6cm): “Granizo” by nssl0001, National Severe Storms Laboratory (NSSL) Collection. Licensed under Public Domain via Wikimedia Commons.

Some things on our planet are so ridiculous, they could very well be the brainchildren of biblical authors. Frogs falling from the sky, crop circles, giant swirling hurricanes, belching volcanoes, sulphur-based life forms and Paris Hilton’s immense wealth (and equally as immense lack of IQ). And then there’s hail. The fact that the updrafts within a thunderstorm can be strong enough to hold grapefruit-sized hail in suspension is nothing but ridiculous and wholly impressive.

Great balls of ice!

How Hail is Made

Hail consists of balls of ice shockingly called “hailstones”. You may even say that hail is frozen rain, but it deserves a slightly more complex explanation than that…

Hail is made within powerful thunderstorms or cold fronts. Cold fronts tend to produce smaller hail that might inconvenience your dog’s plans to go do his business outside, thereby inconveniencing your plans to keep your house hygienic. The large hail responsible for denting cars, destroying crops and severely upsetting your herd of cows is typically associated with large thunderstorm systems that are well-endowed in the vertical and are sustained by powerful updrafts. These traits are especially exhibited by the “Big Daddy” of all small-scale tempests: supercell thunderstorms. These you will find skipping across “Tornado Alley” during the northern hemisphere’s summer months.

Severe thunderstorm across US Great Plains

Supercell thunderstorm with rotating mesocyclone (*swoon!*). The presence of such large frozen water particles within the cloud selectively reflects light towards the lower energy (green) end of the color spectrum, which is why thunderstorms that produce large hail can make the sky appear a ghostly green.

What cold fronts and thunderstorms have in common is that they are both low pressure systems that suck in air and expel it out their rear. Thunderstorms pull in great volumes of warm and moist air, which rise, cool and condense to form towering cloudy behemoths of cumulonimbus clouds. The air, once cooled, loses its momentum and proceeds to sink towards the ground. Together, these two channels of air comprise the updraft and downdraft zones that sustain a thunderstorm: its lungs if you’ll indulge a bit of poetic licence.

Now, as you should know, temperature decreases with height in the atmosphere. That’s why the tops of high mountains are frozen and it’s why you should always, ALWAYS go for a pee before sky diving. At a certain altitude within a thunderstorm, which can soar to as high as the interface between the troposphere and stratosphere at approximately 10km above sea level, the temperature reaches zero degrees Celsius – the temperature at which water freezes. Above this 0°C isotherm (an obnoxious way of saying “line of equal temperature”) all the water droplets in suspension are frozen.

The strong updrafts within a thunderstorm sweep water droplets above the 0°C isotherm where they freeze (consult the pretty diagram below). These pellets of ice then fall back down towards Earth in the downdraft zone, plummeting below the 0°C isotherm and defrosting into big globs of water. This is why thunderstorm rain gets you soaking wet faster than Channing Tatum’s dirty dancing in “Dirty Mike”.

hail-formation-diagram

Image Source: University of South Florida, scholarcommons.usf.edu

However, some of these falling frozen pellets of rain get caught up in the updraft zone again and are swept back up above the 0°C isotherm. Only, they’ve gained a layer of water, which they collected as condensation while chilling out below the 0°C isotherm. This additional layer of moisture freezes, forming a new layer of ice over the original ice pellet.

Large hailstone concentric circles Concentric layers of ice in a hailstone.

 Image Source: “Hagelkorn mit Anlagerungsschichten” by ERZ – Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons.

This process can repeat itself several times and each time, the hailstone will grow larger and larger and larger as it collects more and more layers of ice. The next time you’re in the middle of a raging supercell storm, run outside, collect a couple of decent-sized hailstones, run back to the tornado shelter, bolt the trapdoor, watch your dad arm wrestle said trapdoor with an F5 tornado, watch your dad lose, resolve to become a hardcore white vest-wearing, tornado chasing sexpot with a serious death wish. Oh! And remember those hailstones you collected? Cut them open to see those concentric circles of icy awesomeness.

When a hailstone finally gets too heavy for the thunderstorm’s updrafts to hold in suspension depends entirely on the strength of those updrafts. The stronger they are, the heavier the hailstones. This is why larger hailstones are associated with powerful thunderstorms, such as the Midwest super cells that are sustained by incredibly strong updraft zones.

And when hailstones get heavy, it’s time to run for cover.

Hailstorm damage

Sorry Boys… Size Really Does Matter

Farmers are more obsessed with size than that clutch of vacuous floozies and jockstraps in Jersey Shore. Considering their livelihood depends on it (and not their egos), this is easy to understand and empathise with. But, in no other aspect are they more obsessed with size than with hail. The happiness and health of their livestock and crops depend on it.

Some thunderstorms can create hailstones that are big enough to cave your head in. Even if you do have brains. The next time you’re at a party, scoop an ice cube out your rum and coke and toss it at your mate (preferably the one who’s hitting on your girlfriend). Listen to the dulcet sounds of squealing as it clobbers him in the noggin. Now imagine something easily ten times the size of that ice cube falling thousands of metres (or feet) from the heavens. Yup! Ouch.

Record_hailstone_Vivian,_SD

Ermagherd! Ferkerng HUGE herlsterne!

 Source: “Record hailstone Vivian, SD” by NWS Aberdeen, SD. Licensed under Public Domain via Wikimedia Commons.

On 23rd June 2010, the largest hailstone in recorded American meteorological history fell in Vivian, South Dakota (image above). This great ball of ice weighed in at 0.88 kg (1.93 lbs) and was a staggering (if it had hit you in the head) 20 cm (8 inches) in diameter.

That’s two inches longer than your average you-know-what, tee hee!

Class Dismissed: Your Take-Home Message

Big Hail Thunderstorm

Hailstones are physical evidence of the incredible air circulations going on inside a thunderstorm. Can you imagine how strong air must be to prevent something that weighs almost a kilogram from succumbing to gravity? I don’t know about you, but that blows my mind in the most delicious way. And so we see that thunderstorms are about so much more than just thunder and lightning and the occasional airborne cow.