Shocking xkcd cartoon highlights dramatic shift toward the global warming emergency

For those who don't believe global warming is happening or haven't absorbed how shockingly fast Earth is heating up, an science cartoonist has come up with a dramatic, effective timeline. The inspiration for the timeline was Nasa's recent news that August was the hottest absolute month ever measured.

What's particularly disturbing about the August news is that it appears to have been even hotter than July (though so statistically close that it is difficult to say for certain). Earth's average temperature normally peaks in July. That didn't happen this year, marking yet another milestone in the race to a dangerously hot future.

Nasa's stunning graphics of the problem are effective but don't take the really long view.

Randall Munroe — an artist, physicist, and former NASA roboticist behind the web-comic site xkcd — created a timeline of the past 22,000 years of Earth's climate history. It's juxtaposed with key moments in civilisation experienced by stick-figure humans, albeit presented in a deadpan manner. It manages to be both funny, and in the end, rather horrifying.

Munroe effectively shows how Earth's climate has fluctuated slowly over thousands of years. Then, in the blink of a timeline-eye at the birth of the Industrial Revolution, the temperature suddenly makes a dramatic turn.

One likley future on the timeline continues in a dotted line to far higher temperatures. (There is also an "optimistic" dotted-line future and another one for the "best-case scenario assuming immediate massive action to limit emissions."

The timeline makes clear that this is like nothing nothing the Earth or humans have experienced before, and we don't seem to be traveling in the right direction.

The one complaint among some scientists about Munroe's timeline is that no one has determined the exact temperatures of the Earth around 20,000 BC, which is when Munroe's timeline begins, so it's a bit of a fudge, notes Pacific Standard.

But Gavin Schmidt — director of Nasa's Goddard Institute for Space Studies, who said he consulted with Munroe "a little" while Munroe was constructing his history — also told the magazine that he thought the cartoonist "did a good job."

Check out the full timeline.