Shewee, the water was ball-numbingly cold this morning. Well, at least according to the guys who were mad enough to venture out there to start with. Weak 1-2ft 8 second swell didn't exactly have me running for my board, and just as well. A jog across the road and a cursory toe dipped into the water revealed that indeed there were ice blocks about! Plenty of shell-shocked lil crabs on the beach. Don't blame them, I'd also get the hell outta there at that temperature. Yesterdays Herald article mentioned upwelling offshore as being the reason behind all the cold water, so I decided to check it out. I've mentioned it before in one of my blogs, but hadn't gone into too much detail. How it works is as follows: we have the 'warm' Agulhas current running southwards from Moz down towards Cape Town along the deg of the continental shelf. It's pretty quick, running at about 5-10k's an hour and reaching down to a depth of around 1000m. Cos it's flowing so quickly it causes a dynamic upwelling of cold water from under the current itself which spins up and onto the shelf. Then what happens is that you get these inshore eddies forming on the landward side of the current (again cos it's moering along at such a pace), and these lil things spin off the edge of the current and head straight towards us, carrying that nasty cold water with them. Add some east winds to that - and that just fast tracks the cold water right into the bay. And herein lies the rub - it's gonna get worse! Climate change is heating up the oceans, meaning there's plenty more energy stored in them. And that's kinda like giving the Agulhus current the equivalent of a Red Bull. The thing is now running on serious juice, and picking up some extra speed. What it's doing is then just amplifying everything that happens in the system. So where we had some upwelling of moderately cold water, now we're gonna have lank upwelling of ice-cream headache water. Port Alfred seems to be the main lucky winner in the whole scenario, with a seriously cold upwelling system happening just offshore there. Problem is, with all the east winds, that cold stuff's just getting blown our way. It might have a coupla interesting complications for us, beyond just making us shiver in the surf. There's a theory that maybe the freezing water just offshore is trapping some big fish in the bay - which is maybe why there've been a lot more sightings of our toothy friends? Also, you definitely don't want to be trying to fly outta PE in the early mornings anymore. Fog seems to be coming more of a regular occurrence due to the warm air temps and icy water. Fog = no planes landing = you got up early to get to the airport for nothing! Remember that when booking your tickets kids. Anyhow, kudos to Wes and his mates for braving the 14C water this morning with nothing other than boardies and chest hairs. They actually managed to hold out for 30 minutes, and then only got in cos the waves were just really kak. Respect. Glad to see there're still some tough ou's left! Comments are closed.
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AuthorMillerslocal Archives
July 2021
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