I am Groot

He is staying in his lane of experience which is economics, and how climate change is going to effect our economy in the future. He is using reports made up by climate change experts from the UN, or have they been disproved? 

AFAIK the UN's 'if this isn't stop then that' uses economic damage as the basis for why we have to address global warming. It gives varying degrees of economic damage to different parts of the globe largely depending on their distance from the equator.

As the rate of climate change seem to be accelerating, glacial melt, ocean temperatures increasing, I don't know how anyone can claim to know what the economic effects will be.

As far as floods go, the last one in the Fraser Valley was supposed to be a 100 year flood and that was in 91. Last years was much worse. The severity of fire seasons in BC has also been getting progressively worse. BC's wildfire fighting expenses were 63 million in 2018, 101 million in 2019, 136 million in 2020 and 500 million in 2021. 2021 was an anomaly (hopefully) because of the heat dome but the province is now budgeting 200 million a year for fire fighting.