The video explains the implications of a recent paper written by Hansen and 18 co-authors called Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 ◦C global warming is highly dangerous (pdf). The paper compares what happened during the Eemian interglacial (~120 kya) to what is happening today, and finds many things to worry about (see the paper).

I took an interest in anthropogenic climate change in the late 1990's, about a decade after James Hansen first testified before the U.S. senate about the dangers of global warming. It is now 20 years later, and Hansen's role in publicizing the issue has been much reduced. In 2016, Hansen can only make a video on youtube about the dangers of 2°C of warming and hope people will watch it. To date, about 30,500 people have watched it, including me. I've embedded the video below. You can find a transcript here .

Near the end of the video, we get this from Hansen:

I think the conclusion is clear. We are in a position of potentially causing irreparable harm to our children, grandchildren and future generations. This is a tragic situation — because it is unnecessary. We could already be phasing out fossil fuel emissions if only we stopped allowing the fossil fuel industry to use the atmosphere as a free dumping ground for their waste.If we collected a gradually rising fee from fossil fuel companies, we could phase over to clean energies — if done right it would spur the economy and create jobs.

But that’s a story for another day.

Tragedy in the most profound sense is

a drama or literary work in which the main character is brought to ruin or suffers extreme sorrow, especially as a consequence of a tragic flaw, moral weakness, or inability to cope with unfavorable circumstances...

And thus we see Hansen has misunderstood tragedy. The coming (and present) sorrow and suffering caused by global warming is tragic because it is necessary in the sense above. In the great drama of life on Earth, the main character (humanity) is brought to ruin as a "consequence of a tragic flaw, moral weakness or inability to cope with unfavorable circumstances." I attempted to explain the relevant human flaws, weaknesses and inabilities in the Flatland essays.

Hansen himself is therefore a tragic figure because he can not comprehend or acknowledge that humanity can not act in ways other than what we've already seen heretofore. According to the rules of human nature, Jim Hansen is fated to blame the fossil fuel industry for a crisis which has much deeper roots. He is fated to make videos on youtube which only a relative handful of people will watch. He is fated to explain the climate science to people who, for one reason or another, are unable to absorb his reasoned arguments.

Here's Hansen introducing the transcript linked-in above.

The main point that I want to make concerns the threat of irreparable harm, which I feel we have not communicated well enough to people who most need to know, the public and policymakers. I’m not sure how we can do that better, but I comment on it at the end of this transcript.

Jim, it simply doesn't matter how you communicate the science and its consequences. It is not a matter of doing it better or not, of doing it one way instead of another. In fact, you've done a pretty good job of talking about the science, although your explanations are far too convoluted for the average human to understand.

In so far as global warming is a tragedy in the sense laid out above, it turns out that how you communicate the science has no effect. More subtly, your perceived failures to do a better job communicating the science is part and parcel of the greater tragedy itself. Even me pointing out the climate and other tragedies inherent in the human condition doesn't matter in the end. It makes no difference, in this larger sense, whether I publish this blog or not.

All the world’s a stage,

And all the men and women merely players;

They have their exits and their entrances,

And one man in his time plays many parts...