Below are some excerpts from the book.

Smith looked around the room and cleared his voice. “That is why we are announcing tonight the successful deployment of a global sun shield, now positioned in space, in a solar-blocking orbit called Lagrange point 1, or L1, one million miles from Earth, manipulating specific levels of incoming solar radiation, controlled from here on Earth as required, to bring a balance of climate that will benefit all of Earth’s inhabitants. Lincoln once said, ‘The best way to predict your future is to create it.’ Well, we’ve taken that a step further. We feel the best way to predict the weather is to create it.”
There was a murmur from the audience. Smith put both hands toward them as if comforting a group of children who had just been told there would be no summer vacation this year. “Now, please, I know some may ask why the public was not notified of this decision, or why the people of the world were not asked to debate its merits before deployment affecting the entire world’s population. The reason is simple: We have studied the human reaction to discussions of climate change over many years and, through careful analyses, determined that the chance of worldwide consensus on action was zero; in fact, it was a negative value, indicating guaranteed global social upheaval. To expect that agreement on the climate issue would actually occur is naive; therefore, the commission decided that action was needed to protect the planet and all her species, including the human species.” Smith took a deep breath.

He looked down at his seating chart and called on a woman in the front row of journalists. “Halley, er, Holly Despardeau?”
“Close enough,” said the woman, repositioning herself in her seat. “So why now? I mean why not redouble our efforts in renewables to solve this issue of climate change? Just look at solar—the price has dropped by half, and sunlight is free, at least in that scenario.” Halley appeared seemingly confident that she had made a perfect rationale for pursuing a course of traditional renewable-energy sources, especially solar power.
“Good point,” said Smith, “but as it turns out, our climate models show again and again that the increased warming trend will put us in a cloud-covered earth in fifty years. Simply put, it will be too cloudy for solar panels to work. All that evaporation from even best-case warming models causes condensation—cloud cover essentially—that blocks out the sunlight necessary for solar to be the answer.”

She turned and left the office stunned and with a lump in her throat. When out of Swift’s sight, Petra fell back against a wall for support, staring downward. She felt physically and emotionally ill after hearing Swift’s take on the future. Petra, like most people, assumed the issue of warming a few degrees would be it and nothing more nefarious, but the scenario Swift laid out gave her chills. His scenario did in fact make sense in the context of past perturbations of the carbon cycle. It had happened before, tens and even hundreds of millions of years ago, without the help, or blame, of humans. She began to realize that just because humans arrived on the scene, that was no guarantee that Earth would support the species; there were plenty of times in the past when it would not have.
As Petra walked away, Swift poked his head out of the office and called to her, “Say, Sands.”
Petra pushed off the wall. “Yes?” She tried to compose herself. “You okay?” Swift asked after seeing Petra.
“Yeah, fine. What’s up?” Petra asked, still composing herself and not wanting to appear shaken.
“I forgot to tell you to please stop by HR and sign the nondisclosure agreement about our little chat,” said Swift.
“Nondisclosure?” said Petra, confused.
“Yes,” said Swift. “We want peace up there, not panic. Got it?”
Swift pivoted into his office and sat at his desk with his laptop.

Petra held up a thumb drive and slipped it into the computer. Then, clicking away at the keyboard, she entered the model parameters. She had not heard or seen of any modeling related to the ISMS and assumed it must have been done. Still, some questions ran through her mind. The press announcement said the ISMS would be deployed for five hundred years, so she typed “500 years” for the Earth Systems Model simulation run time. Other parameters popped up on the screen, and Petra paused for a few seconds but answered them as if she were playing Jeopardy:
//Incident sunlight orientation: “Horizontal with mesh obstruction 800,000 kilometers altitude between solar input,” Petra typed.
//Obstruction diameter: “Calculate to block incident sunlight to Earth diameter.”
Petra had to make snap assumptions because she didn’t know the ISMS specs.
//Obstruction orbit: “L1.”
//CO2 levels at start: “490 ppm … we wish,” Petra muttered again until she realized the woman would look up at her each time. Petra smiled at the woman and got back to work, telling herself to stay quiet.
//Albedo: “0.05% increase per year, limit of 35%.” Albedo was reflectivity of solar radiation by cloud cover, snow, or ice.
//Modify based on model feedback results? “Yes.”
//Apply Paleo environmental databases? “Yes.”
//List events: The cursor blinked while Petra thought, and then she typed in events from Earth history she thought should be considered:
• Ocean Anoxic Event 1a
• Ocean Anoxic Event 2
• End-Ediacaran extinction
• Cambrian-Ordovician extinction
• Late Ordovician extinction event
• Silurian extinction
• End Permian extinction
• End Cretaceous extinction
• Paleocene–Eocene thermal maximum
“That should do it for now,” said Petra under her breath. She was aware that Earth’s climate had changed over time. In fact climate change was the norm of Earth’s history, not the reverse, but Petra felt uneasy seeing such a list of events in Earth’s history that surely would have done in the human species. In the past, thinking of each extinction individually didn’t have the same forceful realization of the hit-and-miss survival of life on Earth as seeing them all listed together. And this was not a complete list by any means. For a moment, Petra wondered again if maybe this ISMS thing wasn’t such a bad idea after all.
The screen blinked with a field for “other factors.” Petra thought about what else to add. She recalled Swift talking about gas hydrates, essentially methane trapped in ice, called “clathrates” because of their shape and configuration. The methane clathrates were in the frozen arctic soils and sea floor sediments along some continental shelves, some as close as the Carolina coast. If those sediments warmed enough, massive amounts of methane could be released into the atmosphere. That methane would be twenty times greater in trapping heat than CO2 and cause runaway greenhouse gas conditions. It had happened before.
Petra strained to remember the term for past huge releases of methane, causing or at least contributing to previous mass extinctions on Earth, like a gun had gone off. Then she typed in:
//Consider clathrate gun hypothesis. One more idea:
//Consider erosion of atmosphere by solar wind. That was enough.
The screen flashed “Enter modeler name.” Petra froze; she did not want anyone to know what she was modeling. She typed in “HAL 9000.”

Petra chuckled. She was finally feeling her spirits rise now that she had some time to take in what they had accomplished. She was tired but relieved, and a feeling emerged that she had not felt in a long time, one she had missed: being proud of herself.
“Looking back on all that’s happened on the earth, all the times when conditions would not have supported human life on the planet, it’s amazing we have this window of time,” she said. “We should appreciate it more.”
Swift just nodded and looked out the window.