Animated Daily Sea Surface Temperature Anomaly Visualization 1981-2023 (VIDEO)

Publicly available data provided by NOAA on ocean temperatures every day.  Each day is a separate image.  Although the interface looks very late nineties, there are a ton of options. Visit their site & with a click on a date this data will be neatly called up, parsed for you by their 'THREDDS' program, & quickly visualized by their GODIVA2 browser. 

Try as I might, I could not get their 'animate' button to work for me, so of course I did what anyone would do: download all fifteen thousand two hundred ninety images. (See notes, below.)  

NOTES:

1.  Gold represents no deviation from the mean, with darkening blues for down to 10° C below & brightening reds glowing up to 10° C above it.

2. The video above is the original animation. (The one up at YouTube being a derivative with a smaller footprint, & therefore less information.)

3. Compare to my previous animation, at https://www.youtube.com/watch?v=-NskAtk3tQk:

4. I do not see the same creepy 2023 pattern variation that arose when I animated with screenshots from Earth.nullschool.net. Nor did I see any weird 'granularity' beginning around 2020 & going up till then. So the other weirdness might well be a product of faulty or cascading effects in sensing equipment.

5. For example: https://www.ncei.noaa.gov/thredds/godiva2/godiva2.html?server=https://www.ncei.noaa.gov/thredds/wms/OisstBase/NetCDF/V2.1/AVHRR/198109/oisst-avhrr-v02r01.19810901.nc#

6. Images downloaded using cURL via the command line interface, batch resized & converted to jpg & each image given a text overlay of it's date -- with the invaluable ImageMagick -- via grep assisted shell scripting; then the whole lot made sequential via Automator; after which I pointed ffmpeg at it via the command line to get the MP4 to resize & futz with bitrate framerate encoders wrappers & upload limits.

2023 Sea Surface Temperature Anomaly WEIRDNESS - explanation(s) sought, comments welcome

(Skip to video)

The Setup

Often lately I find myself playing around on my laptop with the most excellent global visualization tool called Earth at  https://earth.nullschool.net.  (Here's an excellent talk on how this came to be by its author, Cameron Beccario (@cambecc):  https://www.youtube.com/watch?v=QXNODLWhSbw).  I usually am perfecting how to tell if a hurricane is forming or, especially in 2023, looking at the off the charts sea surface temperature anomaly, or SSTA.  This is the variation of the surface temperature from the mean for that location, and Earth:Nullschool has it color coded: from just under -10° C (white)  to just over 10° C (off-white), with black for no anomaly, i.e., the sea surface is at the expected or mean temperature.  (At least this is how I understand it; I welcome correction if needed). 

Enter 'The Blob'

So then I hear about the Blob, or Cold Blob, a patch of water off of Greenland that is always, always, always colder than the surrounding ocean.  Always.  Except the video interview that introduces me to this is from 2015 (do a search for 'cold blob Atlantic' videos, most are from 2015-2018), and when I go to look for this on my visualization, it isn't there. 

Time Machine

I click on the Date icon (right next to the 'Now' button) and go back a few years.  There is is, a patch of royal blue near Greenland.  Go back as far as I can, still seeing it.  But clicking is laborious, I want to make a movie....

TIL

...& after a few days of learning how to operate Google Chrome headless to take screenshots, how ffmpeg makes videos from images (& how much it heats up my poor laptop)... 

WTF

...I see something really really odd in the video, a change as of 2023, & I want an explanation.

TIL take 2

...so since the video is glitchy and was hard on my laptop to make I learn the python command to run a baby server so I can use HTML5 & Tim Whittaker's HaniS to point at a folder of images and animate them, & then I learn the ImageMagick commands to batch convert the 3000+ png images to jpg, resize them, & overlay the date so we know what's when...

VIDEO: CAN ANYONE EXPLAIN WHY 2023 LOOKS SO DIFFERENT?  PLEASE.

Basically, the blob is there & things look pretty regular until around 2020, when the pattern gets really... granular, or chaotic... & then in 2023...

Please watch.  Comments most enthusiastically welcome.  Thank you.

A higher quality version is on my YouTube channel, here.

Be seeing you.