Where Is the Epic Put-the-Fear-of-God-into-Them Climate Change Film?

When nuclear holocaust was humanity's greatest fear, a handful of key films explored what effect a nuclear war might have on civilization. Dramatic pictures such as Threads and The Day After and documentaries like If You Love This Planet painted pictures so unbelievably grim that some people my age still shudder with dismay at the memories. It's hard to say how much films like these pressured the world's peoples into making nuclear arms less acceptable and therefore led to the nuclear arms reductions of the 1990s, but there was at the very least some subconscious impact on the public consciousness. 

The movies I mention above were released in the early 1980s, one of the heights of the Cold War, a time when nuclear war seemed to some not only possible, but perhaps inevitable. 

Why then, I wonder, has there not been a single big-budget, mainstream drama about the end of the world due to climate change? I'm not talking about farcical disaster films, but serious dramas that truly capture the existential threat.  

I suspect that one reason is the different natures of the catastrophes. Nuclear war happens suddenly, with worldwide devastation wrought in mere minutes. Climate change is, in human terms, more of a slow-motion crisis. Plus, it's easy to understand the immediate threat of big bombs; the threat of drought, crop failure, sea level rise, and a rising number of extreme weather events feels less like a disaster and more like something that might happen, sometime after I'm dead, in places far away from me. 

I won't be surprised when someone makes this movie, though; a sprawling epic told across decades, from the days in the mid-20th century when the danger was first recognized to the end of days when the world's societal and economic systems can no longer cope with the increasing rate of change and we collapse together into barbarism. 

I hope whoever it is makes it soon, though, because the general public and world's movers and shakers need the emotional gut punch of a Day After or Threads to push us back on track. It may already be too late, of course, but one can hope otherwise.