The seasons idea is interesting -- to me, both proposals feel wrong. I think it's because the weather changes that I perceive seem to lag behind the changes to daylight length by a few weeks.

I would propose boundaries that align partly with how I perceive the weather, and partly with how we plan our year (by months): Summer starts June 1st, Fall starts September 1st, Winter starts December 1st, and Spring starts March 1st.

Oh, I have never heard of seasons starting mid-month. My mind is blown!

In Australia it's just split up by months, with each season being 3 months long:

March 1 - Autumn starts June 1 - Winter starts Sept 1 - Spring starts Dec 1 - Summer starts

Of cause, those in far northern Australia, only really have Dry and Wet seasons. I have no idea when those are.

Does Europe and America really call the summer solstice the “start” of summer. Wow.

In India our summer holidays start at the end of March and finish in the start of June. That’s usually our hottest months too. And a lot of our regional “New Year” calendar’s and related festivals are on April 14th and can probably be considered the start of summer.

There's a significant lag between the longer days and the resulting higher temperatures though, which does make the seasons make more sense temperature-wise.

On the seasons front, traditionally in Ireland winter starts on Halloween (at sunset if you want to be really specific), and so you get winter is November till January, spring is February to April, summer is May to July and autumn is August to October.

That said being an English speaking country and absorbing a lot of media from other English speaking countries, there’s been a slow drift towards the American system making its way in, so younger generations are more likely to use American seasons and older people more likely to use traditional seasons, though you’ll find people of all age groups using either. Certainly they taught the traditional seasons in school when I was a kid, I wonder which they teach now.

(Of course, you could make yet another system based on the weather where summer is approximately two weeks in July, winter is a thing that happens every few years and the rest is a sequence of mild weather with occasional wind and scattered showers)

You can get some black "machinist's layout bluing" which will stain it better than a sharpie would. It's not going to be a perfect color match but better than 50%

You can anodize aluminium black relatively easily, similar to this

https://youtu.be/y8HEZ-x4-_w?t=402

Getting the shade right could be tricky though.

The author seems to not realize the season are about temperature not about sunlight. If you align the season to northern hemisphere temperatures, where the first week of August is usually the hottest, they make sense.