Isn't that only so on one of the hemispheres? Right now, earth is slightly further away from the sun when its summer on the northern hemisphere which means that our summers are some 5-7 days longer than our winters and our seasons are actually less intense here.
In a circular orbit, the seasonal variation is driven solely by the axial tilt and relative hemispherical insolation bought about by earth’s own shadow, and angle of the sun to terrain.
With a variable distance from the sun, the seasons become erratic, as these two variables precess out of sync - you end up with winters in one hemisphere where the earth is close to the sun, making for mild winter and scorching summer in the other hemisphere. Equally you end up with the earth far from the sun, and bitter winters and cool summers. Finally, you have the precessions 180 degrees out of sync, and you end up with almost no seasonal variation.
So - it makes the overall swings far more extreme, but in some phases can result in milder seasons.
The last interglacial (the Eemian [1]) lasted 15k years and was warmer than what we experience today; sea level at peak was probably 6 to 9 m (20 to 30 feet) higher than today; Scandinavia was an island. Then the glaciation returned for 100k years with mile-thick ice sheets covering huge parts of Europe and North America, until the current interglacial got going almost 12,000 years ago. [2]
"The axial tilt varies between 22.1° and 24.5°, over a cycle of about 41,000 years. The current tilt is 23.44°, roughly halfway between its extreme values. The tilt last reached its maximum in 8,700 BCE. It is now in the decreasing phase of its cycle, and will reach its minimum around the year 11,800 CE. ... decreasing tilt may encourage the onset of an ice age ..." [3]
[1] https://en.wikipedia.org/wiki/Eemian
[2] https://en.wikipedia.org/wiki/Last_glacial_period
[3] https://en.wikipedia.org/wiki/Milankovitch_cycles#Axial_tilt...
How do you determine the exact position in a cycle of 400000 years?
Not everyone is required to take Astronomy courses in school. For example, my formal education never included it.
> I am really fascinated to see that Milankovic is finally becoming more relevant today. (Ask about a famous Serbian scientist, and everyone can mention Tesla. Ask for the next one, and observe. But that's a good test
While Tesla was ethnically Serbian, I'd consider him to be an American scientist since that's where he lived for most of his life, and did most of his work. Plus he was born in what is today Croatia. Honestly, though, does it really matter other than for fictional nationalistic bragging rights?
> I bring this up in a comment here, and all I get is downvotes
Because you're acting like a snob?
> It's Milanković actually, and that guy also has his own entry on Wikipedia
Had you taken the care to actually read the article you linked, you'd notice that the name of the cycle is Milankovitch, regardless of the actual name of its eponym:
> The second contribution is the explanation of Earth's long-term climate changes caused by changes in the position of the Earth in comparison to the Sun, now known as Milankovitch cycles
Yes. It matters if one keeps a tally of what one civilization or another did, like we do for ancient times, and the future will do for us for example.
It also matters if one wants to get an estimation which country, kind of educational system, laws, etc, produces more or less good outcomes (e.g. innovation) in this or that field.
And of course, if the person claimed he is so or that, and cherished that, we should respect them, and not rebrand them. For example there are examples of famous immigrants to US, France, and other places, in literary and other circles, that don't like to adopt their country of citizenship as their nationality. For them their culture is always their other one, and their citizenship is only a matter of residence, convenience etc.
No wonder that flat-earthers are still a thing. If that is not basic, fundamental, general education, I don't know what is. The world is officially screwed. I don't give a fuck anymore.
> While Tesla was ethnically Serbian, I'd consider him to be an American scientist since that's where he lived for most of his life, and did most of his work. Plus he was born in what is today Croatia. Honestly, though, does it really matter other than for fictional nationalistic bragging rights?
Exactly, ethnically Serbian, that's the sole reason I used that adjective. Why do you bring up nationalism here? Are we a bit projecting here? I'm not even Serbian or anything close. If you want to consider him an American scientist, that is perfectly fine, you have solid ground for that. Plus, it's pretty irrelevant what the birthplace is known as today. Back then, it was the Austrian Empire, and many Serbs were a part of it at that time..
> Because you're acting like a snob?
A snob? For stating what is a simple and harmless truth? I'd rather say that I caught some subset of the HN target demographic on the wrong foot. But it's okay, no one likes to get called out for their bullshit. Intellectual honesty is dead anyway, in a world where "fake it till you make it" is seriously considered good career advice.
> Had you taken the care to actually read the article you linked, you'd notice that the name of the cycle is Milankovitch, regardless of the actual name of its eponym:
I'm perfectly aware. But I choose to not follow here. You know, English is not the only language on this planet. I am not a native English speaker as well, so why should I care..
No, for being annoying about it.
> I'm perfectly aware. But I choose to not follow here. You know, English is not the only language on this planet. I am not a native English speaker as well, so why should I care.
Because you went and decided to call out an English speaker, who was writing English, on the "incorrect" spelling of an English word? Sure, in Serbian it might be "Milanković's cycles", but in English it's Milankovitch.
It is a horrible test. There’s a large difference between being interested in the history of science, and who did what and where they hailed from, and actually being interested in science.
Just because I don’t care to read tabloids about the personal lifes of actors and where they are from doesn’t mean I don’t like movies.
> There’s a large difference between being interested in the history of science, and who did what and where they hailed from, and actually being interested in science.
I fundamentally disagree. If you are really interested in science, but not in the history of science, you are doing something very, very wrong, and you are bound to repeat a lot of mistakes if you are not willing to learn lessons from history. But my suspicion is, while many people claim to be interested in science, because it's 2018 and it is definitely fancy to do so, they deep down do not care. Participating in bullshit events like "marches for science" is a really poor disguise, in my opinion.
From my recollection of what they covered in school it went no further than that the orbit is an ellipse. I got more detail from my years on the net.
I learned this in school nonetheless, I don't know what so say anymore. Many more had this covered in school as well, I believe, but hey, maybe you simply forgot? I find that lack in general education in that regard a bit disturbing.
But let me compliment you that you actually went ahead and learned a bit more about the details on your own volition. That means there are at least two of us on here..
I was going to mention Mohorovičić [1], but it turns out he was Croatian (which to me means that Milanković and Mohorovičić were both Yugoslavians, but the Serbs and the Croats don't seem to view things that way).
Then I remembered the Serbian-American inventor/engineer Michael (or Mihajlo) Pupin [2], who really deserves to be better known. Besides being an inventor, he won a Pulitzer prize in 1924 for his autobiography, "From Immigrant to Inventor". Anyway, that's the main reason I'm posting this comment, to attempt to rescue Pupin from semi-obscurity.
But while I'm here, I'll mention that I didn't learn about Milankovitch cycles in astronomy courses, but in geology courses, because of the cycles' influence on the timing of the Ice Ages.
[1] https://en.wikipedia.org/wiki/Andrija_Mohorovi%C4%8Di%C4%87
And thanks for the shout-out to Mr Pupin and Mr Mohorovičić, and for providing some links as well, I wholeheartedly approve of any attempts to rescue important characters from their undeserved obscurity. Really appreciate it.
You've managed to be dismissive of everyone that knows slightly less than you, everyone that didn't cover this in school, and at the same time dismissive of everyone that knows much more, climate scientists.
Apparently you think this is universal knowledge but somehow has escaped the attention of climate scientists.
In the context of climate change, when Earth's orbit becomes more eccentric (our path over the next 200k years) seasonal changes increase in magnitude.
[1] https://en.wikipedia.org/wiki/Milankovitch_cycles#Orbital_sh...