Article US government: Climate change is not an existential risk?

[Syne]

If you start with repeatedly disproven claims, lies, and insults, it's just a self-fulfilling prophecy that no one will take you seriously.

[confused2]

Why would I choose 70 years?
CO2 is currently at 420ppm and rising at (about) 2ppm per year. Multiply 70 by 2 and you get an increase of (about) 140ppm, add 140 to 420 and you get 560 which happens to be exactly twice the preindustrial level of 280ppm. Take the average of 560 and 280 and you get 420 .. we're at the midpoint right now. We aren't at an equilibrium temperature .. we don't even know what it is .. but we can reasonably assume it will be higher with more CO2 in the atmosphere .. that is to say global temperature and sea level will rise faster than at present but it gives no indication of how much faster or what the final level will be.

[Syne]

Man, you've lost your own thread. You claimed 70 years until peak oil, e.g. "when fossil fuels start to run out."
Now you're spinning some bullshit about, what, 70 years until there's some hypothetically insurmountable amount of CO2 in the atmosphere.
And you somehow believe you're doing anything approaching a legit cost/benefit analysis. 9_9

[confused2]

If you add 2ppm of CO2 per year for 70 years you get an increase of 140ppm. I don't understand why you would have a problem with that.
If you add 140ppm to the current level of 420ppm then you get 560ppm. I get the impression the arithmetic is the insurmountable barrier at this point.

[confused2]

Hm, Going back to 1954 doesn't look like a good idea so I'm going back (and forward) by 50 years .. 1974 to 2024 and 2024 to 2074. So at the current rate (2ppm/yr) we get an extra (100*2)=100ppm in 2074.

In 1974 we had about 330 ppm (1) and in 2024 we have 420 ppm .. so the average is (330+420)/2 =385ppm
In 2024 we have 420ppm and in 2074 a predicted 520 ppm so the average is (420+520)/2=470ppm

A change from 330 to 520 isn't exactly in the 'small change' range but assuming linearity probably (!) isn't too rash.

If the actual increase from 1974 to 2024 is 0.89C (2) then..
the increase from 2024 to 2074 should be (!) .. 0.89*(470/385)=1.1 C

So a total change over 100 years to year 2074 of 2 C of which we've already had (almost) 1 C.

Comments and/or criticism most welcome.

(1) https://www.acs.org/education/whatischem...curve.html


(2) https://earthobservatory.nasa.gov/world-...mperatures

[Syne]

And? Is that supposed to be catastrophic?
You do know that the levels of CO2 in the atmosphere used to be far greater, right?

[confused2]

And? Is that supposed to be catastrophic?

Particle physics (and weather) often involve extremely rare events and subtle effects, so researchers need to be very certain that their observations are not just statistical flukes.

In particle physics, the commonly used threshold for "beyond reasonable doubt" is a statistical significance of
5 standard deviations (5σ) or greater. This means that the probability of the observed result being due to random chance is less than 1 in 3.5 million. [Thanks 'Pi']

So for events like (say) hurricanes with around 7 occurrences year it would take millions of years to extract a definite 'fingerprint' of global warming.

Sea level rise is the surest indication of warming as it collects up events from the entire planet.

You do know that the levels of CO2 in the atmosphere used to be far greater, right?

Yes, you're right! It's a story of animals, vegetables and minerals. Back in the day nothing could metabolize the carbon taken in by vegetation* .. it just got buried to form the coal seams we find today. Over time bugs evolved to exploit trapped carbon and liberate it into the atmosphere as carbon dioxide. New bugs find new carbon stores which causes waves of increased CO2 in the atmosphere. Humans are just the latest in a long line of bugs to have found ways to extract energy from stored carbon.

If I can be of further assistance please do not hesitate to ask.

Edit
* For how and why plants extract carbon from the atmosphere .. google 'photosynthesis'