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grundar t1_iw3drdc wrote

> Yes, if we can dramatically cut greenhouse gas emissions, we will have less greenhouse gas emissions.

And as a result ~1.8C of warming.

I'm glad we now agree on the main content of my comment.

> They also state that it isn’t a likely scenario as countries over promised and are under delivering

Science requires specifics -- what specifically do they say that you interpret as that?

In general, the sources I've referenced do not say what actions are or are not probable, as they correctly recognize that predicting future human behavior is very hard and not their forte. What those sources do do is examine different scenarios, and analyze what would happen if each of the different scenarios were to occur.

Note that the IPCC and IEA in particular very explicitly call out that they are not saying which scenarios are more or less likely, only what will happen if those scenarios occur.

> There is no popular support for drastic cuts of fossil fuels in those countries.

Yes, which is why the key change is making clean energy cheaper than fossil energy.

Costs have dropped 10x for solar since 2010 (and 3x for wind), and as a result renewables are virtually all net new global power generation. Clean energy isn't suddenly booming because people have suddenly decided to self-sacrifice; it's suddenly booming because it's cheaper.

It's the same for moving away from oil; due largely to a 10x decline in the cost of batteries since 2010, EVs are projected to be a majority of the global car market by 2034 or even 2030 as reality races ahead of predictions.

That is what's driving the transition to clean energy and the subsequent emissions reductions -- economics.

Are national pledges questionable? They're not nothing, but I largely agree with you that they're shaky. The underlying technological and economic changes, though, are what is allowing those pledges to be kept with minimal sacrifice, and those technological and economic changes are the important drivers to keep an eye on.

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Aardark235 t1_iw3x8ke wrote

Here is a better comparison of the current policies that will result in a +2.7C gain by the end of the century vs the unrealistic promises that we will almost immediately drop CO2 emissions in half.

https://www.cfr.org/backgrounder/paris-global-climate-change-agreements

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grundar t1_iw4wrq3 wrote

> Here is a better comparison of the current policies

Did you not notice that they're referencing exactly the same analysis that I did in my original comment? They're linking to Climate Action Tracker, just like I did.

So...congratulations on coming full circle and finally agreeing with the references provided in my original comment, I guess.


While you're there, it may be instructive for you to note that while "current policies" result in 2.7C of warming, "current policies" as of 2018 would have resulted in 3.3C of warming, so "current policies" is very much a moving -- improving -- target.

Indeed, it's likely they'll put out a new analysis after COP27. Every previous major iteration has shown that estimated warming has declined -- for "current policies" as well as for scenarios taking into account pledges -- so it will be interesting to see if that continues to be the case after COP27 and if so how much. We'll see.

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Aardark235 t1_iw50tqd wrote

You are a very optimistic person. For the sake of the planet, I hope you are right.

I am old and cynical for many valid reasons.

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