Tuesday, May 28, 2013

Could geoengineering save us from mass extinction sooner than people expect?

First, let me review the problem. There is serious reason to worry that  the Arctic will melt far enough just in a decade or two, to create something like mass eutrophication of the norther oceans of the world, resulting in the emission of H2S and related molecules which eat up the stratospheric ozone layer, and kill us all by radiation within just a few decades....

Since I want to discuss a possible way out, let me just summarize by pointing to a few recent reviews with important data embedded in them:




Perhaps I should also post a more concise summary, adding material from the Arctic folks...
but not now.

In general -- this situation reminds me of a class I took many, many years ago
under Howard Raiffa, the pioneer of decision analysis, where he reported how the elites of our world systematically underestimate both worst case and best case realities. Both our extreme hopes and our extreme fears logically deserve more consideration than we usually give them.
I don't see any way to GUARANTEE human survival in the face of these new climate issues --
but if HOPE is all we have, we should not underestimate that either.

It is quite clear that 10-20 years are not enough to turn around the CO2 and methane emissions
which drive warming in many parts of the earth. However, there is one important caveat:


It may indeed be that carbon black explains a lot of why the Arctic has been melting much faster than all the models predict. If so, a new priority to reduce carbon black quickly might be one thing which could buy us time. But how much, how fast?


But what about geoengineering?

What about trying to get the capability to  intervene, to prevent our mass extinction by direct action
on the climate even before we reduce CO2 and methane emissions?

I was really delighted to hear that the role of ideology is less implacable and monolithic that it seemed a month ago:

It is quite odd that some liberals are now attacking conservatives for being too interested in geoengineering. "It lets oil companies off the hook!" Well, we have lots of reasons to want to be able to develop nonfossil energy technology, for reasons of national security, with or without global warming. But letting the human species just die, in order to make the oil companies feel bad about what they are doing to us, is a bit too harsh of a punishment in my view -- especially since they would be punishing you and me and everyone on earth.

But -- if we decide that we are serious about geonegineering, and really want to develop the quick-response capability to be able to save our lives if the "unexpected" starts to happen..

HOW? What can we and should we do? The New York Times review (above) is really quite fuzzy,
though it's a good starting point.

They point out that a lot of geoengineering schemes would fertilize the ocean in a way which makes the eutrophication danger even worse...  And the sulfate partices would have a direct effect to make
the ultimate problem, ozone depletion, even worse. Yet if Arctic melting should be avoided that way, that benefit might be enough to offset those direct losses, maybe. Or maybe not.

But what about mirrors in space, which does not eutrophy the oceans or screw up the ozone layer?

(And also, what about geoengineering to restore the ozone layer DIRECTLY? Sadly, I have seen nothing much on that option... maybe we need to explore it further.)

The New York Times ruled on on the basis of "it sounds like science fiction." Yea, and so did airplanes in 1900. That's not what I'd call serious analysis.

So let's run some numbers...

The feasibility is largely a matter of cost, and this past week I had discussions at the International Space Development Conference with two of the world's most important experts on the feasibility of reducing launch costs.

How the rough numbers look to me now..


Lowell Wood (not a fan of space mirrors) says about a million square kilometer of lightweight,
inflatable mirror could stabilize the climate. The solar sail article cites a "sigma" of 5 grams per squatre meter,
or 0.07 for more aggressive new technology.

This past week, I ran into a very serious proposal for a new space aqccess vehicle estimated by
seroius folks to offer about $50/kg launch cost, for payloads of about a million pounds.
(It checked out on my first questions, which most such things do not, but of course it is not
a fait accompli.) At that rate, the JPL estimate of "sigma" would cost about $50 billion,
with the new vehicle... lots of launches. But the advanced solar sail material would
imply more like $1 billion (and fewer launches.) So it's within the pale. I don't know the
issues on getting to the lower weight material.

I was also intrigued by a new report of someone who flew over the Zrctic, to get data on why it is melting
and warming faster than the models predict. It sounds as if carbon black (absorbing llght/heat)
is a major factor. Lots of folks think "hey, carbon black only lasts a couple of decades or so in the atmosphere,
so why pay so much attention to it?" Well, they may be rather important decades, as it turns out.

It suggests to me that the hope of getting to the $50/kilogram option (actually, two competing credible ideas)
is worthy of more priority than I thought... when I consider how quickly the northern ocean transformation may occur,
and the importance of being ready for it.


At www.werbos.com/space.htm, I have posted a link to a summary in Aerospace America of
a more extensive design by Ray Chase to get to $200/pound-LEO, for which we had 90% chance of success using off-the-shelf-technology in about 5 years, using the technology we had at the time.

That's still on the table.

But for $50/kg-LEO... I have had interesting discussions with Dr. Abdul Kalam, former President of India, and with the Policy Committee of the National Space Society.  We really need to study his
key launch ideas more seriously, throuigh more serious funded work... but it LOOKS AS IF his
"Avatar" vision has a good chance of working, and getting us to $50/kg-LEO, perhaps as soon as 10 years from now, **IF** the best US technology can be mobilized and brought to bear, for the
scramjet engines and the hull structure. That's one hope, and NSS is committed to making that hope as real as possible. More precisely, this month the NSS Policy Committee unanimously passed the motion:

This committee strongly supports the effort to build new collaboration between US and India and relevant US allies in the areas of affordable and clean energy for use in space and on Earth from space, and low cost access to space, within the larger context of widening the door to human settlement of space and a more prosperous and peaceful world.

But we need all the hope we can get. I was very excited last week to hear of a new design, like Chase's, but estimated by extremely competent folks to offer
$27/pound-LEO. "How?" As in Chase's design, it would be based on a rocket engine, a rocket engine -- but it would exploit economies of scale, to be able to lift million pound payloads. "What about the total vehicle weight?" I asked.
"Chase tells me he sized it to about 10 tons payload, because when the vehicle weight gets to be more than a million and a half pounds, kit's
hard to use airport style operations, because you crush the runway."
Their approach: water takeoff and landing, like the old Spruce Goose.
That HAS worked before...  and they had more detailed notions of vehicle structure, well-grounded in the old McAir Space Works (now owned by Boeing).

So I really hope one or both of these lines works out... it may indeed be a matter of life or death, yours and mine.. (at least if we hope to live for more than a couple of decades. I wouldn't want the whole species to die of old
age at about the same time I do...). But, you out there: how much do you care whether you live or die? What would you be willing to do to increase your chances?

Best of luck..


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