Tomorrow’s World by Davie Henderson Page B

happening is to look at the polar regions. As the climate warmed and the icecaps began to melt, so less heat was reflected—vegetation and bare rock absorb a lot more of the sun’s energy than snow and ice—and the pace of melting increased. The melting of the ice created its own terrible momentum. Self-accelerating processes like that were going on all over the planet.
    â€œTake the tundra: methane which had been trapped in frozen organic matter was released as the permafrost thawed. It’s a much more harmful greenhouse gas than carbon dioxide, so the more of it that was released, the warmer things got—melting more permafrost and releasing yet more methane.
    â€œLikewise with the forests: as they were cut down and burned, more carbon dioxide was released—and of course there were fewer trees to help with its absorption.
    â€œThen there were the oceans: vast and powerful, yet deceptively sensitive to changes in temperature.”
    â€œIn what way?” a Name asked.
    â€œThe warming of the surface shut off the circulation that brought nutrients up from the depths. Without those nutrients, the algae that absorb carbon dioxide from the air died off. It was a double disaster: the dying algae released methane and carbon dioxide into the atmosphere, and at the same time reduced the ability of the ocean to soak it up.”
    â€œWhat date was the tipping point reached?” Frankie asked, to more sniggers.
    Annie allowed herself a not unkind smile at the naiveté of the question. “It’s not something we can put an exact date on, because we’re dealing with continuous processes, and a great deal of them,” she explained patiently. “But it’s generally agreed the point of no return was passed in the mid-2020s. Before then the consequences of man’s abuse of the environment were just beginning to impact on everyday life, but they were felt as irritations and minor inconveniences. There was only the occasional catastrophic event, like Hurricane Katrina.”
    â€œThe one that flattened New York?” Frankie said.
    â€œWrong!” one of the Paretos crowed.
    Annie ignored the Pareto, and said, “It was Hurricane Zena that devastated New York. Katrina hit New Orleans. They were both warning signs—and perhaps if they’d been heeded, it wouldn’t have been too late.
    â€œBut people chose to treat the symptoms rather consider the root causes, and by the early 2030s the symptoms were too severe to treat—and so was the cause.”
    â€œWhat sort of things do you mean when you talk about irritations and symptoms?” a student somewhere behind me asked. I guessed it was a Name: we love the details that give color; Numbers are just interested in facts and figures.
    Annie said, “I’m talking about things like how breathing unfiltered air began to result in respiratory problems; how exposure to even modest amounts of sunlight, washing in untreated water, or getting caught in showers of rain started causing skin problems. Not to mention the long-term health concerns associated with drinking untreated water and eating unprocessed, unpurified food. The lifespan and fertility of people, plants and animals markedly declined, while the incidence of mutations increased.”
    â€œThings like your arm,” one of the Paretos said with undisguised mockery. I could quite happily have choked him for his callousness. Worryingly, I could quite happily have choked the other Pareto, too.
    Annie evinced no such malice. “Yes,” she said quietly. “Like my arm.”
    â€œWhy don’t you get a graft?” a Number sitting a couple of desks along from me asked.
    Annie looked him straight in the eye and said, “If you don’t know, nothing I can say will make you understand.”
    I sensed the Number’s quiet seething. Even at that age they hate to feel there’s anything they don’t know or are incapable of