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Comment by bloudermilk | Hacker News Reader

The warming of our atmosphere is easily predicted by basic science related to greenhouse gasses and solar radiation.

This isn't disputable as randomness any more than an object can be said to have randomly fallen to the ground when dropped.

Here is one of countless sources you can find that explain this principle and the consequences: https://www.climate.gov/news-features/understanding-climate/...

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>In fact, the last time the atmospheric CO2 amounts were this high was more than 3 million years ago, when temperature was 2°–3°C (3.6°–5.4°F) higher than during the pre-industrial era, and sea level was 15–25 meters (50–80 feet) higher than today.

Doesn't this mean that the correlation between CO2 levels and temperatures isn't that big?

I can come up with a couple alternatives to your explanation:

1. Our current carbon levels haven’t been high long enough for their total effects in temperature to be felt yet, given the size of the system they must affect. 50 years is a blip on geological timescales.

2. There are cascading effects to high CO2 levels that will take longer to manifest themselves and which will raises the temperatures further. Permafrost melting and releasing methane is a possible example.

The orbit of the earth around the sun, and the activity of the sun itself are also possible culprits. I'm sure actual climatologists have a better explanation.

It doesn't have to be large if you throw enough CO2 and other greenhouse gasses into the lower atmosphere, it just has to correlate. Far more concerning is the rate of change, which is unprecedented. There could be unforeseen impacts from the speed, and a new equilibrium from the already achieved temperature increase could be hundreds of years away as billions of cubic kilometres of ice takes a while to melt. 2C by 2100 is a reporting convenience.

Ozone depletion measured CFCs in parts per trillion (US short scale).

The correlation has a significant lag on it because of the huge thermal capacity of water and the even bigger latent heat capacity of ice melting. The antarctic ice sheet will take a long time to melt.

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