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.
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!
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:
- 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.
- 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.
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).
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.
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.
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
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.
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
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!