green swan

Forbes magazine briefly described a green swan event as

“a climate event that is unexpected and rare, with far-reaching impacts.”

https://www.forbes.com/sites/servicenow/2021/06/18/sustainable-finance-surviving-the-green-swan/

This concept is obviously related to Nassim Nicholas Taleb’s renowned book The Black Swan: The Impact Of The Highly Improbable.

However, if that description leaves you wishing to know more, the BIS has devoted an entire book to the issue of how Central Banks can mitigate the impact of climate change on the financial system; The green swan Central banking and financial stability in the age of climate change.

https://www.bis.org/publ/othp31.pdf

overhaul

The word overhaul can be used both as a verb and a noun. It refers to the fact of changing a system to make it work better.

Deutsche accelerates overhaul of corporate bank after Brexit

Although it is often combined with adverbs such as radically or thoroughly, strictly speaking that shouldn’t be necessary as the word itself already implies making big and extensive changes.

Northern Ireland moves to radically overhaul legacy gambling rules