There are lots of stories out there about people who begin to discover one common type of psychic power, who then must cope with very unpleasant images of some murder in the city they live in... But how would it feel if you confronted images not of one person killed, but of Billions of faces dead in a rictus of surprise about something they didn't think applied to them...
The evaluation below was motivated in part by such images, but it is not in principle avoidable. Is it avoidable in practice? That might depend on you.... =============================================== =====================================================
But in all fairness… I find myself really overwhelmed by the huge contrast between what we need to do to survive, in the climate area, and what
is really likely to be possible in the political world we live in (like the nice but small story above). On top of a lot of other things, I am still reeling from the pictures posted at:
So why would these pictures depress me? Hint: it's not about global warming as such.
Many of you already know that I was deeply shaken up by a talk at NSF in 2009, sponsored by the NSF Geosciences Directorate (which I do NOT represent!),
which was basically just an introduction to the paperback book, Under a Green Sky, by Peter Ward, whom they introduced as the world's top expert
on the concrete facts of the 5-12 mass extinctions which earth has experienced in the past. (The book is just $7 from amazon, and written for non experts;
I have posted a 3 page "cliff notes for scientists" version, if anyone is interested.)
Ward's first key finding is that the levels of H2S in the atmosphere and radiation have several times reached levels which were high enough that they would have killed every human alive on earth -- if humans had been alive at the time. In the most recent event, the eocene/paleocene discontinuity, there are primates and big cats before the event -- but not after. They re-evolved from scratch, from the mouse. But prior events were enough to kill the mouse too.
Ward said, at the end of his talk, that he has tracked recent data, and sees a repetition of the same patterns he saw in the past.
After that, he fell into a bit of speculation. But more detailed studies, such as work of Kump at Penn State, showed that there are really just two key variables
which drive the production of H2S in the ocean which puts us at risk: (1) the level of nutrients flowing into the ocean
(now high, due to agricultural runoff, which we simply cannot afford to zero out now); and (2) the level of oxygen in the deep ocean, due to thermohaline currents (THC), which Ward also agrees play a central role.
So it looks to me (just me, not representing anyone else) that the THC are what stand between us and "a rerun of PT," in which even the mouse would die.
That NOAA website shows us what is really happening in the southern THC, which is the primary source of oxygen to the deep ocean.
It is not good. The current is ALREADY largely shut down, due to the way that fresh water melting off of the continent floats on the surface,
preventing the earlier mechanism of high-oxygen salt water sinking from the surface to the depths. The main lung of the planet is already "under water," choked off. Fortunately, the earth does not suffocate in just three minutes of oxygen deprivation; the curve suggests that we still have 40 years left, for the 2/3 of the
system where oxygen is lowest. Basically, that means the Pacific Ocean. But if the Pacific Ocean starts to "turn black" in 40 years…
Compare that with "vigorous expensive proactive measures" like the Waxman bill, which would have reduced US CO2 emissions by about 40% after a century (according to the official DOE/EPA projections provided to EPW)… and consider there is little evidence on the horizon that we would move even that "fast"….
I am asking myself very seriously: what could really matter, in the face of all this? Peanuts don't matter. But then: what does?
What kind of path leads to the highest probability of humans actually surviving?
In most of human history, most people would then be told fiercely and proudly that the answer is to sacrifice someone
to the gods, to display loyalty to whatever got us into the situation in the first place. I would claim that attaining a level of sanity (and sensitivity)
much higher than that is one of the key variables in determining whether we have any real hope here. But of course there are many concrete things
which call for re-examination as well, in light of the real schedule we are facing.
Of course, I have also asked a lot of people to please refine the story further, so that I have more to go on than this kind of quick eyeballing. But tis is all I have found anywhere as yet.
Best of luck,
As I probe that NOAA story further, I have definitely found a less pessimistic version of the story. There is a paper (easy to find in google scholar) by Esmee M. van Wijk and Stephen Rintoul, in Geophysical Research Letters 2014, which argues that the oxygen at the ocean bottom in the south has NOT declined over the past fifteen years or so. I am not sure how to reconcile that with the clear evidence of shutdown in most of the convection currents from the south pole, and the stories about how the fresh water is creating a layer above the salt water where the oxygen used to get down to the deep ocean. The article does say that oxygen levels are unchanged for the densest water (heavily oxygenated salt water), and that the AMOUNT of the densest water is decreasing. So perhaps it is like the "chemocline" in the Black Sea, where life above the chemocline is unchanged by the chemocline itself is rising to the surface. Thus I am certainly not reassured as yet. But this is the only paper I have seen so far which really addresses the oxygen issue at all in this specific context. (I certainly have met a lot of folks who know this area who are quite worried, and perhaps the Wijk paper is intended to discourage such worry… like the folks who said Ebola would never reach the US at all. But who knows?) The scary image published by NOAA seems to be based on papers by Purvey of the University of Washington. Best of luck,
Paul
P.S. Some folks out there still ask "But is climate change our fault?" Who the hell cares, if
our lives are at stake. The question is what we can do about it. My knee jerk reaction is to
think of ways to advance low-carbon technology in a more effective way, and also to think about geoengineering. There is no sure panacea, but I do view more vigorous directions in space
as one of several important things to get deeper into. But am still mulling through various options.
================= A bit more explanation I gave to the lifeboat list: Unfortunately, the issue in the Antarctic is not whether the surface water temperature rises by 1 degrees C. That was the question I was asking last year, before I knew as much as I do now about the Antarctic system. (Not that I claim to know it all yet!)
In the Arctic, when it is mostly all at the same prevailing salinity as in the North Atlantic, it is true that zero degrees C is the critical tempertuare which shuts off convection temperatures -- because zero degrees C is the
temperature of maximum density for water that salty. (That is a very solid fact, That's all a matter of how temperature affects density of water.
a standard textbook kind of thing.) That's enough to figure out the coming tripwire in the North -- but not enough to track the shorter-term issues involving Greenland which I now understand much more clearly than I did last year.
For the Antarctic and Greenland), the key issue is the way that fresh water is less dense than salt water. (This year I told myself: 'Duh. Don't you remember that stuff about how easy it is to float on the Great Salt Lake!") The fresh water melting off the Antarctic and off Greenland creates a layer offresh water atop the Salt Water, and blocks the current of heavy slat water from the surface. No salt water on the surface. Off Greenland, I have the impression that this inlux is less now than it was a few years ago; only so much ice on Greenalnd. The Gulf Stream dropped maybe 30-50% for a few years, causing a great scare, but came back, because this is a"flux effect
not a stock effect." (Reference to Jay Forrester's book System Dynamics --
not an endorsement of everything he says, but basic system dynamics is important here.)
But there is more ice on the Antartic, and there is no sign of it running out for a very long time. Instead of a mere 30-50% reduction, it looks to me as if more than half the oxygenating currents of salt water from the surface are already gone... maybe a lot more than half. And that already happened. The refernces I gave tree back to that. With the current more than half gone, the next phase is for oxygen deplegtion to get to critical level.
When is that? The figure from NOAA on that website I sent out shows where the deep oxygen is,
and how fats it is going away. It looks to me like 40 years left for the Pacofic Ocean part of it.
Best of luck,
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Friday, October 3, 2014
Death by Black Water and Green Sky
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