The Mysterious Oceans

Some years ago, before I got divorced a couple of times and lost most of the toys that make life fun,I used to have yachts. And I used to buy yachting magazines. Once, I came across this article which has never left my memory. I turn it over from time to time, think about it, marvel at it, just for the shear joy of it.
It seemed that the writer of the article had noticed that there seemed to be a lot more boats getting into trouble off the New South Wales coast than normal. And the weather didn't seem to be any more inclement than expected for the time of the year. So the correspondent got in touch with the Australian Navy and asked them if they had any clues. Yes, apparently they did.
It appears that a huge amount of water had welled up from the deep ocean and raised the water levels around the Solomon's (I am pretty sure it was there but don't mind being corrected) by about 30 cms. Yes. A foot. And all this water had to go somewhere. So it joined the East Australia Current. Shouldn't need to explain where that is. And this unexpected water had increased the current from 3-4 knots to 5-6 knots. And since the prevailing winds were from the south east pushing against an increased southerly current flow, the waves were much bigger than anticipated given the wind strength. So Boaties got into strife when they shouldn't have. It took a month or two for the current to slow down. There was that much water. Where the hell did it come from?
No-one seems to have any theories except those that resemble guesswork.
Don't you love stuff like that?