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A Pocket History of MacroEngineering: The First Millennium

Written by Gregory Benford

Illustrated by Adam Burch

From the standpoint of a person in that distant past age around the year 2000, the central issues of the next thousand years would seem bizarre. But then, the previous millennium would have looked outrageous to either a king or a peasant peering forward from the year 1000. This Pocket History contains Historical Highlights, in a form intelligible to all forms of humans, even down to Traditional Classic Body Types of circa 2000.

The ebb and sway of political factions, and then of species-based opinion, should not obscure humanity's steady march. There was an ebb and sway to the human prospect, mostly about how much we should weigh upon our world. As the centuries rolled on from 2000 A.D., the multiplying human forms moved toward greater control of their environment. But they did not do this without constant voices that doubted the wisdom of it.

This has been a theme of our species since we separated from the chimpanzees some six million years ago:

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2000-2150: The Earth Stewardship Era

In the latter half of the 21st Century the runaway greenhouse effect caught everyone's attention, especially after a billion died of the effects. This forced Green Puritans to consider planetary management. Warmed-over TwenCen objections to wise, planned human intervention faded as the true, already existing impact of human actions became obvious.

Humanity had been unthinkingly altering its world for millennia. Ice core samples showed that this began around 1000 B.C. with agriculture, which destroyed forests, released carbon dioxide and cut off the ice age that had kept humanity in poverty. To be sure, the early empires destroyed much of their rich lands. Northern Africa and what was once called the Fertile Crescent all became deserts. But the urge to make the world better, or at least distant, was strong. We were the breed of chimpanzee that restlessly moved over the horizon, after all, seeking fresh vistas.

Even so, resistance was strong. The Kyoto Accords of the early 21st Century had utterly failed to constrain the rising load of greenhouse gases. By 2060, amid storms and droughts that afflicted so many, the only argument was over whether thoughtful action was better than rash measures.

In any case, Stewardship soon became essential, following the several human diebacks in the tropical nations. Most of the oil was gone and replacement oil drawn from tar sands loomed as a mega-polluter. The planet needed cooling, fast.

Changes of cities' reflectivity eliminated their "heat island" effect, cutting air conditioning costs—simply by using white roofs and streets, and planting trees. The next Stewardship Stages stimulated cloud generation over tropical oceans, where reflected sunlight efficiency is highest. This went hand in hand with political necessity. The economic uplifting of poverty regions followed, and tropical manufacturing plants sent particle-rich plumes downwind, to grow clouds in daytime and fade at night.

Capturing carbon dioxide from the air, principally by depositing farm crop waste in the deep oceans, offset the fossil fuel burning of the developing nations. The crisis seemed to ebb.

Climate management became routine by 2140, but there was no rest for those weary of Stewardship. Other effects came into play, altering the planetary balance. Just as in the early 21st Century, early signs of a coming shift in climate—this time toward an ice age—met with disbelief. Radicals demanded new measures. Conservatives who profited from the current ideas opposed them.

Another long battle got fought out in the scientific community. Then government got involved, slowing down the debate. Yet another crisis loomed, the opposite of the last one. To avert this cooling trend and advancing glaciers meant reversing the solution—by spreading dark soil on polar caps. New atmospheric engineers suppressed the once billowy clouds in the tropics, letting those lands warm again.

The lesson was now clear. Earth had lurched first in one direction, then another. Human beings were the dominant ecological agent, like it or not.

Once taken up, guidance of the biosphere supporting 12 gigafolk could not be renounced, or else face the demise of whole societies. Geospheric Stewardship became the greatest moral imperative.

The Green Puritan movement was outlawed—but only for a while.

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2200-2500: New Atmospheres on Two Worlds

Since Stewardship worked on Earth, why not afar?

As part of the general uplifting of humanity, we had begun gathering resources from beyond our moon. By 2100 metals had become harder to find in the Earth's crust, and more costly and damaging to extract. There were plenty of metals in the asteroid belt. Inevitably, we went to get them. Bringing them to Earth, smelting them in high orbits—all this helped fuel an expansion of the global economy.

But to support this industry demanded resupply of the Asteroid Anarchy from nearer that Earth—that is, from Mars. But working there was difficult, under a thin atmosphere and with little water.

Stewardship could apply there, as well.

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The renegade Green Puritans tried to stage a revolt against the idea. The Red Mars Brigades used dire warnings and then terror to fend off the planetary engineers, but they were hopelessly outnumbered. Rocks, it turned out in the end, did not have rights.

Using the same dark soil deposition strategy on Mars melted the poles, releasing carbon dioxide and water. Discovery of Martian water reserves not too far beneath the red crust stimulated widespread pumping. These caused a quick greenhouse buildup in the thin atmosphere. That further melted some surface deposits, driving a slow accumulation of gases. Funded by the Fogg Foundation, this work continued until people could walk the surface wearing only pressure masks.

The Martian population spread across their arid lands, an area equal to the continents of Earth, with fresh vigor. They hunkered down each time a fresh, piloted comet came arcing in with new water. Robotic craft liberated these from the perpetual icebox of the far outer solar system. They fell down gravity's long gradient and came slamming into the upper Martian air, spreading moist wealth.

Good enough, but chilly Mars gets only half the sunlight of Earth. There is another spot at just the right distance from the sun, and near Earth, too. But with no air at all: the Moon.

For some time, lunar pioneers had been drilling their shelters. and uncovered deep ice beds. Venting of these made a thin atmosphere. Filmy clouds formed, the first in four billion years. This gave the pioneers an idea.

By that time the most valuable bulk commodity in the inner solar system had become light elements, gathered from cometary nuclei. The inner system is dry and at the bottom of a gravitational well, while at the top of the well, the outer system is wet with frozen ices. These swing in slow orbits between the vast cold bodies of Uranus, Neptune and Pluto. Slightly changing the velocity of an orbiting chunk of mostly ice and dirt could send it plunging down the well.

Harvesting such icebergs led to the "wild west" phase of water prospectors. For a small investment of velocity change, far "uphill" from the parched inner worlds, they could get rich. Their infalling rock and icebergs lit Earth's night skies with thousands of outgassing tails. Traders quickly sold these to development firms. Flown by their own gas pressures to landing sites, the dirty bergs dropped into the thin atmospheres of Mars and the Moon, blasting crater-basins. The new air of mostly water vapor changed quickly under the pelting of solar ultraviolet. Water gave hydrogen, which quickly escaped into space, leaving a growing bounty of oxygen. Add other active gases, released from the world's crust, and presto!—a new technology of atmosphere building.

Martian entrepreneurs quickly blew bubble domes, using the rims of impact craters as starters. These domes got outfitted with soils and cultured with nanotech and bacteria. Moisture came to the red plains that had not known running streams for billions of years. Designer plants sprouted beneath skies that roiled with their own evolving clouds. Where the sky had been black and star-filled, ruddy sunsets spread.

Earthside, in the desert nations now drained of their oil, immigrants looked skyward. They were used to dry lands and had little prospect on Earth now. Islam found a new frontier. In the scarred craters recently blasted by comets, domes rose with mosques at their centers. Condominiums opened within 100 days of impact. Miners, manufacturers and even tourists bought them. They even had real estate agents.

On the Moon, hundreds of comet heads slammed into the ancient plains of dark lava. The atmosphere grew from the billowing splash and spray of massive icy chunks. To have an