Unless posted:

the bitcoin of weed posted:

i read all that and still don't know what el niño, the beautiful baby boy, is

Taima posted:

Ah. This is a good point, my apologies, let me elaborate-

1stGear posted:

so the sahara is going to become beautiful grassland and the libs are complaining about it

Taima posted:

Ah. This is a good point, my apologies, let me elaborate-

I hate to be vague here, but we're not exactly sure what causes these flips because modern weather tracking has only existed for a short time in the grand scheme.

That being said, we know that one happened after the 97 El Nino, and that moved the global system to a new configuration that (imo) very clearly supported La Nina-biased activities from 1997 until the beginning of this year. This bias has had tremendous negative effects on SW America, for one. And we now think that a flip back to positive bias has potentially happened due to back to back La Ninas which have evolved over the last few years, leading to a possible super El Nino in the winter 23-24.

The negative bias we've been in has had many broad implications, here are a few. While La Nina is NOT the opposite of El Nino, the effects of +ENSO and -ENSO tend to opposite each other, so if you want to know how a possible upcoming +ENSO bias would present you can more or less flip these attribues:

- La Nina bias tends to supercharge the Indian Ocean, which has lead to decades of indian ocean dominance in terms of strong, consistent storms. This has cemented the east indian ocean (in particular the blessed wave zone of Indonesia and its close geographical friends).

- It also takes the brakes off the atlantic ocean and, generally speaking, allows more hurricanes to form as seeds off west Africa, leading to more active seasons on average (typically due to a slackening of wind shear in the main development regions).

- It pools up water in the west pacific as enhanced trade winds which, on average, force additional water against the maritime continent region.

This is actually an interesting point; the Pacific Ocean is actually not level/flat. This will take an image to show:



This is the mechanism that allows kelvin waves. The rotation of the earth causes the trade winds:



With me so far? So the water is pooled up in the West Pacific. We can actually measure this with satellites, and it's a key way that we measure the overall heat content in a given thermocline- the water is actually humped up compared to other nearby water and a satellite can see that and go "oh there's more heat there".

When trade winds begin to slacken and even reverse in the beginning of a +ENSO event, that's what a kelvin wave is! The water wants to move east by nature because it is piled up!. So you can think of the warm water movement east not as a push, but more of a lack of pull!

The trade winds create the inbalance as a side effect of the earth rotating. This is why the east pacific is cold. All of the surface water, naturally warmed by the sun, is forced west due to the trades, piling up water in the west pacific and then allowing its release during a +ENSO event.

That means, at its core, that the pacific ocean is like a giant bathtub, and the trade winds are like someone in that tub pushing water to the far end, and +ENSO is, at its core, just a pushback mechanism of the oscillation that moves the imbalance of warm water created by the constant push west, to slosh back east!

It's not all good news though; the far east pacific upwells cold water as part of the circuit created by the trades as seen here:



That upwelling brings incredible amounts of nutrients to the east pacific, making the far east pacific region one of the best fishing regions and a key bread basket for the area and broadly the world.

In that sense +ENSO can disrupt the global food supply. And this leads to another interesting point- has anyone noticed that the water in the east pacific, where upwelling occurs, is muddy? It's not clear. This is due to the upwelling of nutrients and material.

The clear, beautiful water we see elsewhere is actually, in part, a function of its lack of nutrients and other detritus. It's more "dead" at its core than the nutrient rich waters occurring in the east, so clear water is essentially just dead water, in some ways.



Anyways I'm getting distracted and typing too much. To answer your question simply, the event that may have just flipped us back to +ENSO bias might be the last three years in which we have had sequential, back to back La Ninas. That is likely the flipping point that brings us back to a +ENSO biased-period in which the current forming El Nino is just the kickoff (and broadly speaking, big El Ninos usually bookend these changing of decadal bias).

And for the record, La Nina is not the opposite of El Nino. La Nina is just an enhancing of the trade winds that already occur, it is not a dynamic event in itself. It's just more of the same regime. It's El Nino that stands alone as a reversion of these systems and therefore a buckling of the entire ocean/atmospheric connection and global circulation.

I'm intentionally not describing all of the mechanisms of ENSO btw, that would take all day. But for example, a +ENSO biased regime would see, on average, less rainfall in the Pacific Northwest, for instance. This is because the average jet stream position is forced southwards during a strong El Nino, taking the primary storm track from the PNW down to Calfornia.

And yeah, that would mean that in a +ENSO biased system, the average jet position would in fact be southward-influenced. Unfortunately climate change is pushing the jet north, which is a whole other topic, but a super El Nino will temporarily counteract this movement and force the jet back south (along with a juicing it!) and correspondingly, the jet normally moves even further north in La Nina. The following images shows the two general configurations of +ENSO and -ENSO:



It's important to keep in mind though that climate change is disrupting the way the ocean/air reinforced systems of the world operate and that appears to be changing how variable inputs into the system, change the system. So who knows how this will all work in, say, 15 years. One would assume that the general mechanics would hold, at least in strong events, as they take total control of the global systems.

It's much more "up in the air" (hah just a lil weather joke for ya) how climate change will influence the outcome of less strong events, along with the nature and effects of extremely important sub systems of global circulation like the MJO (Madden Julian Oscillation).

Strong +ENSO events tend to dominate the MJO, causing it to largely disappear, but it's a huge part of the normal non-influenced weather pattern:



The MJO moves through the world circulatory system and enhances/suppresses convective forces there (rising/falling air) and it's super cool- have yall noticed that weather often moves in phases? 2-3 weeks of rain, then 2-3 weeks of suppressed rain? That's partially due to the cyclic nature of the MJO. This is getting well beyond the scope of my post though so I'll stop, cheers

Taima posted:

e: happy to go into anything people want to know about El Nino. I was a surfer in Santa Cruz CA for about 20 years before ultimately moving to the Seattle area about 5 months ago. During that time I was fortunate enough to live one block from first peak Pleasure Point and also, later on, two blocks from the Santa Cruz Harbor, which is one of the best waves in the world when it's on.

El Nino is the best thing that can happen to you as a surfer in California for a shitload of reasons- it basically upgrades huge swaths of California into an entirely new surfing coastline with amazing waves everywhere you look.

It also significantly decreases the rainfall in the PNW among many other things. I'm tempted to go crash in CA this next winter and get back into surfing for a while... we'll see.

Anyways, good times, let me know if you have any Qs. ENSO is extremely close to my heart as a surfer and casual meteorologist!

skooma512 posted:

Great write Taima. And I appreciate the detail that El Nino doesn't necessary mean CA gets soaked, I've seen El Ninos be dry and La Ninas be wet.

Also shout out to the El Nino of '97. I remember garbage cans were getting carried away by the water in the gutter, something I don't think I've seen since in that area. Also remember all the lunches in the auditorium. A steaming LAUSD chicken patty sandwich under the rain shelter, the auditorium damp with tracked in water as the scholastic book fair took place.

skooma512 posted:

La Ninas be wet.

SirPablo posted:

Just tell me if I need to buy a tarp and what size.

Traxis posted:

That year was rad, my Dad wrecked the family station wagon by driving it into a flood control channel that had 4 feet of running water.

goochtit posted:

goochtit posted:

https://twitter.com/PaulKPIX/status/1638325128881905665
https://twitter.com/CHPSanFrancisco/status/1638326882910474240

Mirconium posted:

Does... Does that count as a typhoon? Since it's in the pacific and all?

the bitcoin of weed posted:

i read all that and still don't know what el niño, the beautiful baby boy, is

Platystemon posted:

No.

If it got winds going that qualified it, it would be a hurricane, same as the ones that occasionally hit Mexico’s west coast or Hawai‘i.

quote:

Fujiwara effect, Fujiw(h)ara interaction or binary interaction, is a phenomenon that occurs when two nearby cyclonic vortices move around each other and close the distance between the circulations of their corresponding low-pressure areas.

Spaced God posted:

Land/waterspouts form entirely different from tornados. They rely on vorticity already in the air rather than from a mesocyclone updraft

Koirhor posted:

tornados in LA hurricanes on SF, many such cases

Gunshow Poophole posted:

lol this was the one that was "rebuilt" with dogshit inferior steel for the lowest possible price right

this is gonna go great@!!