Climate Phenomenon ‘Atlantic Niña’ is on the Verge of Developing

[Elderberry]

Legal Insurrection by  Leslie Eastman 8/27/2024

Whatever the reason for the development of the Atlantic Niña this year, there is no climate emergency.

A few days ago, the publication NewScientist published an article with a click-bait headline: Part of the Atlantic is cooling at record speed, and nobody knows why.

It turns out the headline is not entirely…accurate. The temperature drop is part of a climate phenomenon known as the Atlantic Nodal Mode. The pattern is like the Pacific Ocean’s El Niño/La Niña cycles but more localized.

The natural climate pattern swings between cold and warm phases every few years. Sea surface temperatures (SST) in the eastern equatorial Atlantic have a somewhat surprising seasonal cycle. The warmest waters of the year occur in spring, while the coolest waters occur during the summer.

    This summer cooling is because of winds that act on the ocean surface. Earth has a year-round rainfall band around the tropics. Driven by stronger solar heating, this rainfall band migrates northward during the summer in the Northern Hemisphere. The regular rainstorms draw in air from the southeast over the equatorial Atlantic.

    These steady southeasterly winds are strong enough to drag surface waters away from the equator, which brings relatively cold water from deeper ocean layers to the surface. This process, known as equatorial upwelling, forms a tongue of relatively cold water along the equatorial Atlantic during the summer months.

    However, every few years this cold tongue is substantially warmer or colder than average due to swings of the Atlantic zonal mode. Cold events are referred to as Atlantic Niñas; warm events are referred to as Atlantic Niños.

What perplexed scientists in this case is that the weaker southeasterly winds were not anticipated to be strong enough to initiate an Atlantic Niña.

    The Atlantic cool pool of water typically develops when southeasterly winds flow into a band of persistent clouds in the intertropical convergence zone. The winds blowing over the ocean stir it up in a way that draws deeper cooler water to the surface.

More: https://legalinsurrection.com/2024/08/climate-phenomenon-atlantic-nina-is-on-the-verge-of-developing/

[catfish1957]

Hurricane season statistically is about 35-40% over and there is already so much discussion around why the ATL sector has gone quiet. 

I've watched and studied these things since I was a child, and part of that fascination is the utter unpredictability.  What many don't realize first of all, is that there is a "randomness" that the models just don't pick up on.  Every sat frame is roll of the dice, and for cyclogenisis, it takes a low, low sheer, low dust, and a warm environment with enough atmosphereic spin to make it happen.

One thing though not an oddity, has impacted more this year, as the Cape Verde has progressed, is what I am seeing around the ICTZ at 10-15N Latitude.  When you see a lot more ITCZ waves at lower latitudes...   5-10 Lat. vs. say 10-15, can make all the difference in the world as far as tropical development. 

Can that change between now, and November 30?  Absolutely, and I think we as coastal residents, sure don't need to let our guard down.  My one by far biggest fear right now?  It has been an amazing quiet season in the GOM to what now appears to run through September 1.  That lack of storms to cool off surface temperatures, might be a situation, where a monster might form.  No storms, generally 90 degree GOM water,  quick forming low in the Bay of Campeche, with minor sheer, and steering currents.   Then add a mid-CONUS high that accentuates the pathway northward?.....  Look out.

Yogi Berra once wisely opined....   "It A'int Over Until It's Over".   I don't think we are through with this season yet.

One factoid that isn't that very well known, is that there has never been a major hurricane strike after October, due to enough fronts and troughs that tend to steer storms North and East.   Looking at all the data, I don't think anything can be ruled out this year.   Want to get an idea when the GOM is over heated?  Watch the radar 4a-7a, and see the diurnal coastal convection.   The GOM is boiling over, so cross your fingers.