Nonsense. The scientific consensus does not simply say that one thing or another will happen. There is a number of possible scenarios each of which is assigned some likelihood according to modelling(informed by empirical data). No serious scientist is saying "X will happen and that's it". That's an inherently unscientific statement.
There’s no plausible scenario where climate change drives global GDP growth negative over the next 50 year. None.
Yea uncontrolled climate change will make life worse than had it not happened. But no it will not outweigh the cumulative beneficial effects of baseline economic growth.
Your can't know that, there's too many variables. Let's assume a terrible scenario with massive heatwaves across the Middle East and Central and Southern Asia (like the ones that have already happened, including recently, in Iraq and and India) that get too frequent and unbearable. Add in food supply problems due to droughts, fertilizer shortages, etc. Now you have millions of migrants going to Europe , or at least North. No one can reliably predict how such a scenario plays out, migrant crisis are unpredictable.
