The acrid tang of coal smoke hung in the air of the Vatican's trial chamber. James Hansen dabbed his forehead with a handkerchief, the morning heat already building despite the thick stone walls. Through the high windows, he watched the haze from Rome's countless chimneys paint the sky in shades of amber and gray.
Melchior Inchofer paced before him, sandals whispering against the flagstones. The prosecutor's fingers worried the brass crucifix at his neck as he searched Hansen's face. "You were seen distributing these... papers." He lifted a sheaf of parchment covered in graphs and calculations. "Claiming that our very industries anger God's creation."
"Not anger," Hansen said, his voice steady despite his racing heart. "Simply change. The numbers tell their own story."
From his elevated seat, Pope Urban VIII shifted, the motion sending his shadow dancing across the wall. His fingers drummed against the carved armrest – a habit, Hansen had noticed, that emerged when curiosity wrestled with doctrine.
"These numbers," Urban said, leaning forward. "Explain them." The Pope's eyes flicked to the window, where a layer of haze had turned the morning sun into a copper disk.
Hansen rose, his modern shoes squeaking against the ancient floor. "Your Holiness, may I?" He gestured to the windows. At Urban's nod, he approached one. "Look there – the glass works along the Tiber. Every day they burn coal, every day that smoke rises. Now, imagine each smoke particle as a tiny piece of glass."
Inchofer's crucifix clattered against its chain. "Pieces of glass in the sky? Have you lost your—"
Urban raised a hand, silencing him. "Continue."
"Just as your gardeners use glass to trap the sun's warmth in your orange groves, these particles..." Hansen paused, watching understanding flicker across Urban's face. "The evidence mounts with each passing season. The Alpine ice retreats. The winters soften. The harvests come earlier."
Urban's fingers stilled their drumming. He stood, his robes rustling as he descended the dais. The assembled cardinals murmured in surprise as their Pope approached the window beside Hansen. For a long moment, Urban studied the hazy sky, his reflection ghostly in the glass.
"And if..." Urban's voice dropped to nearly a whisper. "If what you say is true, what would you have us do? Close the glass works? Shutter the forges? Return to darkness?"
Hansen noticed the Pope's hands were trembling slightly. "Not darkness, Your Holiness. Change. Different ways to—"
"Enough!" Inchofer's voice cracked through the chamber. "Your Holiness, this is no different from Galileo's heresy. He too claimed his numbers could explain God's mysteries."
Urban's shoulders tensed at Galileo's name. He turned from the window, his face now a careful mask. When he spoke, his voice carried the weight of centuries of doctrine. "Dr. Hansen, you place a heavy burden on this court. To accept your claims would be to accept that man can alter God's creation itself."
"With respect," Hansen said, "we already do. Every cleared forest, every quarried stone, every plowed field..." He gestured to the hazy sky. "And now, it seems, every coal fire."
The chamber fell silent save for the distant tolling of church bells. Urban returned to his seat, shoulders bowed as if beneath an invisible weight. When he spoke again, his voice carried a note of something Hansen couldn't quite identify – regret, perhaps, or resignation.
"The church's position is clear. These matters are the province of divine will, not human industry." He straightened, authority returning to his bearing. "Dr. Hansen, you will serve in the papal coal mines until you recant these dangerous ideas."
As the guards stepped forward, Hansen caught Urban's eye one final time. The Pope was again staring at the hazy sky, his fingers having resumed their restless drumming.
"And yet it warms," Hansen said softly.
Years later, when summer storms battered Rome with unprecedented fury and the Tiber swelled with melting Alpine snow, some would remember the trial of the man who tried to warn them. In the Vatican's archives, Hansen's papers slowly yellowed, their graphs and numbers waiting to be rediscovered – patient as the warming air that proved them right.