Per the below report by Morgan Stanley, it will cost $50 Trillion to stop global warming by 2050.

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Is that a big number?

Well, the current estimate of World GDP is roughly $80 Trillion/year.  This is expected to double, to $160 Trillion by 2050.

Therefore, over the 30 years, the $50 Trillion to stop global warming equates to roughly 0.014 of world GDP.

By itself, $50 Trillion is a very big number.  But, spread over 30 years, and all the world economies, it is a very small and achievable number.