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Comment by abakus | Hacker News Reader

How much of the global warming can be explained by this increased sun activity?

Almost none [1]. In theory, solar radiation has been decreasing a bit, so we should have cooled slightly over the past 50 years.

[1] - https://climate.nasa.gov/faq/14/is-the-sun-causing-global-wa...

So the sun is more active but irradiance is decreasing?

see the link IvyMike posted below from the same group

Is the little hump inn temperature in the 1940s interpretable? Is it possible this is from the mass industrialization during WW2?

No, the little hump during the war is caused by the fact that before and after the war there were various groups sampling sea surface temperatures with various techniques, but during the war only the Americans kept recording these temperatures.

From the article, at the very end: "Whether this effect could have provided a significant contribution to the global warming of the Earth during the last century is an open question. The researchers around Sami K. Solanki stress the fact that solar activity has remained on a roughly constant (high) level since about 1980 - apart from the variations due to the 11-year cycle - while the global temperature has experienced a strong further increase during that time. On the other hand, the rather similar trends of solar activity and terrestrial temperature during the last centuries (with the notable exception of the last 20 years) indicates that the relation between the Sun and climate remains a challenge for further research."

keeping in mind that was in 2004 and a bunch of further research has happened.

It would be nuts if high solar activity spurred abundant food and thrust humanity into the electrical age. There's gotta be some big trigger why we suddenly have all this tech within 200 years after 100k years of modern humans walking about as cavemen

10000 years of unprecedented stable temperature. See Attenboroughs new documentary on Netflix!

For the trigger in the last 200 years, it is just fossile fuels. Having all this energy provides us with enough food and comfort to survive, thus lot's of spare time and spare manpower dedicated to research and improving tech. It also feeds all these machines we are making.

Going back to renewable will be tough (but is mandatory). We are a species that has been high on cocaine for a couple of centuries and we just realized that it slowly killing us, and it is running out anyway. Our only option is to sober up.

"all this tech within 200 years after 100k years of modern humans walking about as cavemen"

I think that is a misconception. Research and development was done for millenia, and everything is build from the previous. That is how we arrived here and today.

The picture you paint; no technology for 100k years and then suddenly technology out of nothing (or a single event); is just wrong.

It is a common misconception and I wonder where it comes from.

We had writing, pack animals, various types of "primitive" technology for many thousands of gears. Then boom. Within 300 years we go from horses to leaving the planet. There's been more technological advancement in the last few hundred years than all of human existence.

We hit some kind of tipping point based on previous development, or some other trigger that hasn't been identified

Zooming in on an exponential curve doesn't change the shape, is the idea, I think. Nor does it show a discontinuity or inflection point.

I'm not saying I know for sure this is the right characterization of the history of human technology, but I think the typical alternative to your view is that it is.

Sadly not much. The stratosphere is getting colder, while the troposphere is getting hotter, and the overall energy the earth is getting from the sun is sensibly the same. See https://earthobservatory.nasa.gov/world-of-change/Solar (it was a quick search)

A very large portion, not all, not little.

https://en.wikipedia.org/wiki/Solar_cycle#/media/File:Sunspo...

Notice the Modern Maximum starting around ~1800 which is also when all the graphs of global warming show increases; whereas normally the industrial revolution is blamed.

Maunder minimum -> https://en.wikipedia.org/wiki/Little_Ice_Age

Medieval maximum -> https://en.wikipedia.org/wiki/Medieval_Warm_Period though our data is far less clear about that period of time.

Fundamentally, you can look at this graph. https://en.wikipedia.org/wiki/Geologic_temperature_record#/m...

The climate warms and cools quite regularly. The Earth warmed 6 celcius over the last 20,000 years without our help.

https://en.wikipedia.org/wiki/Eemian about 115,000 years ago it was 1-2 celcius warmer. Which is roughly what is currently being predicted as part of climate change by 2100.

An absolutely tiny and negligible amount, almost immeasurably small.

According to some researchers, pretty much all of it. Take a look at the list of skeptical (and frequently demonized) scientists here: https://thebestschools.org/features/top-climate-change-scien...

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