worst case scenario

Scientists have been looking at best, middling and worst case scenarios for anthropogenic climate change for decades.......why it always so difficult and controversial to write about the worst cases.

There are basically three (somewhat overlapping) reasons:

1. The credibility problem: What are the plausible worst cases? And how can one tell?
2. The reticence problem: Are scientists self-censoring to avoid talking about extremely unpleasant outcomes?
3. The consequentialist problem: Do scientists avoid talking about the most alarming cases to motivate engagement?

    -- Gavin Schmidt, climate modeller at the NASA Goddard Institute for Space Studies and Earth Institute at Columbia University in New York 

the-best-case-for-worst-case-scenarios