Does man-made global warming keep you awake at night? Does it give you nightmares? Read Martin Rees. He writes that mankind has only a 50:50 chance of surviving this century.
Must be a wacko, right? Sir Martin Rees is Astronomer Royal, a professor of cosmology at Cambridge and until recently president of the Royal Society.
In “Our Final Hour” he analyses threats to the human race that may wipe us all out:
- Superintelligent machines may replicate themselves again and again with the rate of innovation racing towards a singularity, ie it runs away into infinity.
- Nuclear weapons disaster: The proposition that nuclear weapons can be retained in perpetuity and never used, accidentally or by decision, defies credibility.
- Bioerror or bioterror: The first refers to the potential for accident in the laboratory that becomes uncontrollable. Sir Martin writes that he has a US$1000 bet placed that bioerror or bioterror will kill a million people before 2020.
- Nanotechnology: Nanomachines that can assemble themselves may become more omnivorous than any bacterium, proliferating until they consume all life and cover the planet with “grey goo”.
- Asteroids striking the planet can cause mass extinction. Such an asteroid would need to be 10km in diameter. Smaller asteroids one kilometre across are 100 times more numerous. One hundred metre sized rocks hurtling through space are 100 times more numerous still. Fifty-metre wide asteroids hit Earth once a century. “There is a 50 per cent risk of a Tunguska, Siberia, type meteorite somewhere on the planet this century.” Then there is the risk of such a large rock from space splashing into an ocean causing a tsunami that kills millions.
- Super-eruption: Massive volcanic eruption that blocks out the sun for a year or so, like the one in Sumatra 70 thousand years ago.
- Erosian of biodiversity: “We are burning the books before we have learned to read them” (Robert May).
- Global warming: The sun goes through cycles (flares, sun spots and so on) that have a roughly 12-year span. These affect the average temperature along with other factors such as the earth’s tendency to lurch from ice age to ice age every 100,000 years with little ice ages in between. Nevertheless, Martin writes, even a one per cent chance of human-induced atmospheric changes causing a sudden extreme climatic transition — such as a “flipping” of winds and ocean curents –is disquieting enough to justify precautionary measures.
If your masochism is rubbing along nicely with your misanthropy, this book is for you.