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Bushwhacker42 t1_ivuac8r wrote

Serious question, I thought the glaciers have been receding since the end of the last ice age, like 10k years ago, long before the combustion engine… were these glaciers around BEFORE the ice age? Have there not been times when the polar regions were tropical? Environments change, you can see how much water once flowed through deep canyons. Where I live was once a giant lake through the Jurassic and Triassic times.

I know there is huge impacts from humans on our environment, but… doesn’t nature just kinda change periodically too?

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Swarna_Keanu t1_ivuu9yo wrote

Not at the speed right now, and if it weren't for us adding IR reflecting gasses to the atmosphere we would be in a cooling phase.

That is the simple physical effect. Some trace gasses, like CO2, Methane and water vapour (among others) reflect infrared energy but let the rest of the energy spectrum pass. As Sunlight hits the Earth part of the infrared wavelength is reflected back into space. Most of the energy passes through. The Earth reflects some of the sunlight, but in that process the light is shifted more towards the IR - and the more trace gases are in the atmosphere the more that reflected shifted towards IR right bounces between them, staying in the atmosphere for longer, and in that process heating it up, before, eventually, finding a way out to space.

That is - basic energy transfer and quite simple Physics. So far we assume that Eustice Foote was the first to uncover it - so, we understood since about the 1860s. https://physicstoday.scitation.org/do/10.1063/pt.6.4.20210823a/full/

We know it is us as the CO2 added to the atmosphere carries a clear Fossil Fuel signature - the isotopic count of Fossil Fuel emission is different than "fresh" CO2 and - and we tried loads - there's no other source than our action for the type of CO2 thats increasing.

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Climate_and_Science t1_ivv3iw2 wrote

The last ice age ended at the start of the Holocene 11,700 years ago. There was a continued slow warming up until about 10,000 years ago. For the next 4000 years global temperatures were fairly static. About 6000 years ago temperatures again began to slowly decrease until the start of the industrial revolution. There are large changes in natural climate related to energy input and atmospheric constituents. Humanity is altering those atmospheric constituents.

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Bushwhacker42 t1_ivvc2hh wrote

Thank you this was actually very insightful! I’m going to do some more reading into this!

My son got really into dinosaurs, recently learned raptors lived closer to our era than they did to t-Rex. Crazy world history

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