The Seas Could Turn to Sulfur

Question: What non-greenhouse extinction events have happened in the past, and are they likely to recur?

\r\n

Peter Ward: Well, we certainly know that we were hit 65 million years ago by a very large rock from space, Hollywood knows this with the two blockbusters, “Armageddon” and “Deep Impact,” so it must be true. It was really interesting, in ’95, Spielberg sent his minions to a conference to where a number of us were attending about this particular hit and indeed, there is a great danger out there. We are surrounded by asteroids, some become berth crossing. Jupiter has a way of perturbing comets and sending them from stable orbits to earth-crossing orbits. We will get hit again. How big the hit will be is only a matter of time until we get something the same size that killed off the dinosaurs, should humanity last long enough that is. But that size hit looks like only once every 100 million years, or more. We haven’t had a hit that size for the last 500 million years. So, it does look like it is a rare event to have something that big; a 10 kilometer asteroid hit us.

\r\n

Question: Given the low number of extinction events in recent Earth history, are we “due” for another?

\r\n

Peter Ward: Well, no, it’s just the whole sense of when is it going to happen again and it appears that most of the big mass extinctions have been caused by these nasty volcanic events. The last one didn’t cause a mass extinction. It was in the Tertiary Period. This was in my own home state, Washington State, the Columbia River Basalts. Out came all this basalt, as liquid lava, and a lot of the carbon dioxide came out too, but not enough to cause the earth to go into a really nasty mass extinction. The mass extinctions caused by the basalts again, are simply by heating the world. Now when you heat the world you heat the pole more than you do the equatorial region. When that happens, you start losing circulation. The only reason you have wind now is you have a hot spot and a cold spot and they’re trying to equilibrate. Well, an ocean current you have the same thing. You have a cold Antarctic and then you warm them up, the ocean circulation system is dampened down; there’s much less heat difference.

\r\n

So when we heated the poles to the point that there is no longer – or already in a very sluggish ocean circulation, the ocean is going oxic, they lose their oxygen. They only keep oxygenated now because of this vigorous mixing. Well, even when you have oxygen in the atmosphere and contact with the surface, once you slow down any circulation, that whole basin can lose this oxygen. The Black Sea is the same case. It’s sits under a 21% oxygen atmosphere, and yet the Black Sea, except for the top several meters, in anoxic. It’s black because it’s producing a lot of sulfur-producing bacteria and there’s very nasty gasses that are produced.

\r\n

We now think the big mass extinctions were caused by global anoxia. The oceans themselves so sluggish that the hydrogen sulfide bacteria are produced in huge areas of the ocean bottom bubbles up to the surface and starts killing things; rotten egg killing. It would be extremely nasty. Hydrogen Sulfide poisoning is a horrible death. Two hundred hydrogen sulfide molecules among a million air molecules is enough to kill a human. I mean, just breathing in 200 of those little things amid all the million you’re got in oxygen and boom, you’re down, horribly down.

\r\n

So, this is a really nasty poison and it was certainly present in past oceans during these short-term global warming events. That’s why it’s really spooky what we’re doing now.

Recorded on January 11, 2010
Interviewed\r\n by Austin Allen

From asteroids to worldwide hydrogen sulfide poisoning, extinction expert Peter Ward offers a diverse menu of scenarios for humanity’s demise.

Malcolm Gladwell live | How to re-examine everything you know

Join Radiolab's Latif Nasser at 1pm ET on Monday as he chats with Malcolm Gladwell live on Big Think.

Big Think LIVE

Add event to your calendar

AppleGoogleOffice 365OutlookOutlook.comYahoo


Keep reading Show less

To be a great innovator, learn to embrace and thrive in uncertainty

Innovators don't ignore risk; they are just better able to analyze it in uncertain situations.

David McNew/Getty Images
Personal Growth
Madam C.J. Walker, born Sarah Breedlove, was America's first female self-made millionaire.
Keep reading Show less

Study: Private prisons result in more inmates, longer sentences

The Labour Economics study suggests two potential reasons for the increase: corruption and increased capacity.

Politics & Current Affairs
  • After adopting strict sentencing laws in the '80s and '90s, many states have turned to for-profit prisons to handle growing prison populations.
  • A new study in Labour Economics found that privately-run prisons correlate with a rise in incarceration rates and sentence lengths.
  • While evidence is mixed, private prisons do not appear to improve recidivism or cost less than state-run facilities.
  • Keep reading Show less

    Is this the world map of the future?

    A vertical map might better represent a world dominated by China and determined by shipping routes across the iceless Arctic.

    Strange Maps
    • Europe has dominated cartography for so long that its central place on the world map seems normal.
    • However, as the economic centre of gravity shifts east and the climate warms up, tomorrow's map may be very different.
    • Focusing on both China and Arctic shipping lanes, this vertical representation could be the world map of the future.
    Keep reading Show less

    The art of asking the right questions

    What exactly does "questions are the new answers" mean?

    Videos
    • Traditionally, intelligence has been viewed as having all the answers. When it comes to being innovative and forward-thinking, it turns out that being able to ask the right questions is an equally valuable skill.
    • The difference between the right and wrong questions is not simply in the level of difficulty. In this video, geobiologist Hope Jahren, journalist Warren Berger, experimental philosopher Jonathon Keats, and investor Tim Ferriss discuss the power of creativity and the merit in asking naive and even "dumb" questions.
    • "Very often the dumb question that is sitting right there that no one seems to be asking is the smartest question you can ask," Ferriss says, adding that "not only is it the smartest, most incisive, but if you want to ask it and you're reasonably smart, I guarantee you there are other people who want to ask it but are just embarrassed to do so."
    Quantcast