Tag: weather

Buys Ballot’s law

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I honestly thought* when I saw this that it was how Trump “won” the election, but as probably all my readers already know, Buys Ballot’s law is:

the relation of wind direction with the horizontal pressure distribution named for the Dutch meteorologist C.H.D. (Christophorus Henricus Diedericus**) Buys Ballot, who first stated it in 1857.

It’s a rudimentary method of estimating the position of varying centres of local atmospheric pressure from the prevailing wind direction.

Obvs.

Basically, it works around the relationship that (theoretically) states that the angle between the wind and the pressure gradient is a right angle. That means that in the Northern Hemisphere a person who stands facing away from the wind has high pressure on the right and low pressure on the left; in the Southern Hemisphere, the reverse is true.

We’re in the Southern Hemisphere [checks quickly… yep], so that means that if I stand with my back to the wind, then the low pressure area will be on my left (to be more accurate, it’s actually just slightly forward of my left), and the high pressure area on my right.

But why would I need to know this? Well, I probably wouldn’t, because I’m not a seafarer, miles out in the oceans. And if I did need to know it, then I’d just look at the nearest computer and it would show me where everything was. But in 1857 and for a long time before and afterwards, that wasn’t an option, because the internet was still dial up and that meant that you had to be attached to a really long cable.

Not possible in the middle of the South Atlantic (I am reliably informed).

So this law allowed sailors to estimate where the storm centre was, and thus allowed them to try to avoid it. Of course, you might not have been able to avoid the storm completely, but you could avoid the most dangerous quadrant – that is, the section of the ocean in front of you where the chances of damage from the storm was highest (Northern Hemisphere – front right, Southern Hemisphere – front left).

Less damage in those days (and maybe still even these days) meant more chance of survival.

There are a lot of factors that can mess up the wind/pressure relationship – it doesn’t work near the Equator, for example. But we’re not [checks quickly… nope] near the Equator. And though technology has far outpaced Buys-Ballot and his work, his law obviously still holds true. We just do things differently now.

Next time it’s a bit windy, cancel a marathon give it a go, then impress your friends by comparing your estimates with your modern day synoptic chart.

.

* I didn’t, this was just for comedic value.
** Crazy name, crazy guy.

Good idea

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Tonight’s plan for a beer and curry night seems to have been one of the better decisions I have made of late. At the time of writing, we’re 60mm deeper in water than we were this morning, and it’s dark and grey and stormy out there, with no signs of letting up any time soon.

It’s already added 87,704,000,000 litres to our dams in the last week.
No big issue with that – I might need to water my lawn in December.

Anyway, the good news is that with a beer expert…

I didn’t know what the word for this was, so I asked Google.

Beerologist, libationist, beer devotee, wert guru, beer maven, beer expert, hophead, pisspot, a tippler, a grog artist, a boozer, a beer buff, a slops surveyor, an ale addict, a hops handler, a quaffer, and the chairman of the brewed.

I was looking for a technical, official term, but I got given this. Unhelpful.

Anyway, as I was saying, the good news is that with a beer expert a pisspot coming over this evening, I have got some different beers in to taste – mostly local, but some from Germany, and one from Belgium – and I have cooked up two moerse curries: a lentil and butternut korma and a great-smelling, masala-style chicken dish. There’s naan, there’s achtar (mango, obvs) and there’s homemade raita with fresh mint plucked from the garden before things out there got scary.

We’ll light the fire up (spoiler – it’s already lit) and play pool, listen to the latest tunes from the hit parade, and enjoy some heartwarming food and company.

Tomorrow might be a little iffy, but let’s deal with that if and when we need to, because tonight promises to be a lot of fun.

A quick post on a rainy day

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Yes, seriously: a rainy day.

We don’t get many of them in Cape Town at this time of the year.

Anyway, two things to cover today. The main one being the widespread outrage* at the lack of a beagle update in yesterday’s post. I won’t be making that mistake again.

The beagle is doing fine, thank you very much. A first check-up with the vet this morning was passed with flying colours and we are now moving on towards bandage removal next week. Stitches and staples will come out the week after that, and then there’s this crazy plan to get her into a swimming pool for some hydrotherapy.

Good luck with that.

The other thing is to do a control image for yesterday’s Heathrow picture. Because how do you know that it isn’t always that quiet (although, you do).

So here’s that one for you. Some catch-up going on.

On that note, we’ve got a quiet day overhead today, with all the local planes taking off to the North, and not bothering this side of the peninsular at all.

Like how I tied that all together at the end?
Mmm. Me too.

* I got a whole email

Sun stats

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Another lovely day here today and the forecast looks set for more lovely sunny days in the week ahead:

Those temperatures aren’t anything to email home about, but it’s nice enough and, as Mrs 6000 pointed out, it’s hardly summer, is it? Which it absolutely isn’t, no. That would only start on the 1st or the 21st of December, depending upon which system you’re using.

But we shouldn’t be complaining, especially when looking back over at the UK. This image has been doing the rounds over the last 24 hours, indicating the number of hours of sunshine around the UK, the Isle of Man and Ireland over the first 7 (seven) days of November.

Ouch. Eina. My fok. Goodness gracious.

Bearing in mind that London is sitting on an average of about 9 hours 20 minutes of daylight each day, they could have had over 65 hours of sunshine. They got 2.
The Isle of Man – averaging just over 9 hours of daylight last week – got not a single hour.

In seven whole days!

Aberdeen was the big (and rather unlikely) winner. 8¾ hours of daylight each day, and a whole 13 hours of sunshine in seven days. That’s 21% of their daylight as sunshine. Incredible. Their local Burns Unit must be bursting at the seams, just like it is in late January each year.

We made hay (not literally) while the sun shone today, with the Boy Wonder driving himself and his friends down to Agulhas for a long weekend, and LM 6000, having recovered from her singing last night, riding a horse over some big sticks, rather amazingly.

But now it’s time to sit back with a glass of local red, and catch up with the Youtube videos I haven’t had time to watch this week. I’ll be incredibly knowledgeable and a brilliant photographer in about an hour.

Just watch. Literally.