Forty Signs of Rain. Kim Stanley Robinson

The two men made quite a contrast: Drepung young and tall, round-faced, with a kind of baby-fat look; Rudra Cakrin old, small and wizened, his face lined with a million wrinkles, his cheekbones and narrow jaw prominent in an angular, nearly fleshless face.

      The wrinkles were laugh lines, however, combined with the lines of a wide-eyed expression of surprise that bunched up his forehead. Despite his noises and muttering under Drepung’s account, he still seemed cheerful enough. He certainly attacked his pizza with the same enthusiasm as his young assistant. With their shaved heads they shared a certain family resemblance.

      She said, ‘I suppose going from Tibet to a tropical island must have been a bigger shock than coming from the island to here.’

      ‘I suppose. I was born in Khembalung myself, so I don’t know for sure. But the old ones like Rudra here, who made that very move, seem to have adjusted quite well. Just to have any kind of home is a blessing, I think you will find.’

      Anna nodded. The two of them did project a certain calm. They sat in the booth as if there was no hurry to go anywhere else. Anna couldn’t imagine any such state of mind. She was always in a tearing hurry. She tried to match their air of being at ease. At ease in Arlington, Virginia, after a lifetime on an island in the Ganges. Well, the climate would be familiar. But everything else had to have changed quite stupendously.

      And, on closer examination, there was a certain guardedness to them. Drepung glanced surreptitiously at their waiter; he looked at the pedestrians passing by; he watched Anna herself, all with a slightly cautious look, reminding her of the pained expression she had seen earlier in the day.

      ‘How is it that you came to rent a space in this particular building?’

      Drepung paused and considered this question for a surprisingly long time. Rudra Cakrin asked him something and he replied, and Rudra said something more.

      ‘We had some advice there also,’ Drepung said. ‘The Pew Center on Global Climate Change has been helping us, and their office is located on Wilson Boulevard, nearby.’

      ‘I didn’t know that. They’ve helped you to meet people?’

      ‘Yes, with the Dutch, and with some island nations, like Fiji and Tuvalu.’

      ‘Tuvalu?’

      ‘A very small country in the Pacific. They have perhaps been less than helpful to the cause, telling people that sea level has risen in their area of the Pacific but not elsewhere, and asking for financial compensation for this from Australia and other countries.’

      ‘In their area of the Pacific only?’

      ‘Measurements have not confirmed the claim.’ Drepung smiled. ‘But I can assure you, if you are on a storm track and spring tides are upon you, it can seem like sea level has risen quite a great deal.’

      ‘I’m sure.’

      Anna thought it over while she ate. It was good to know that they hadn’t just rented the first office they found vacant. Nevertheless, their effort in Washington looked to her to be underpowered at this point. ‘You should meet my husband,’ she said. ‘He works for a senator, one who is up on all these things, a very helpful guy, the chair of the foreign relations committee.’

      ‘Ah – Senator Chase?’

      ‘Yes. You know about him?’

      ‘He has visited Khembalung.’

      ‘Has he? Well, I’m not surprised, he’s been every – he’s been a lot of places. Anyway, my husband Charlie works for him as an environmental policy advisor. It would be good for you to talk to Charlie and get his perspective on your situation. He’ll be full of suggestions for things you could do.’

      ‘That would be an honour.’

      ‘I don’t know if I’d go that far. But useful.’

      ‘Useful, yes. Perhaps we could have you to dinner at our residence.’

      ‘Thank you, that would be nice. But we have two small boys and we’ve lost all our baby-sitters, so to tell the truth it would be easier if you and some of your colleagues came to our place. In fact I’ve already talked to Charlie about this, and he’s looking forward to meeting you. We live in Bethesda, just across the border from the District. It’s not far.’

      ‘Red line.’

      ‘Yes, very good. Red line, Bethesda stop. I can give you directions from there.’

      She got out her calendar, checked the coming weeks. Very full, as always. ‘How about a week from Friday? On a Friday we’ll be able to relax a little.’

      ‘Thank you,’ Drepung said, ducking his head. He and Rudra Cakrin had an exchange in Tibetan. ‘That would be very kind. And on the full moon, too.’

      ‘Is it? I’m afraid I don’t keep track.’

      ‘We do. The tides, you see.’

       THREE Intellectual Merit

      Water flows through the oceans in steady recycling patterns, determined by the Coriolis force and the particular positions of the continents in our time. Surface currents can move in the opposite direction to bottom currents below them, and often do, forming systems like giant conveyor belts of water. The largest one is already famous, at least in part: the Gulf Stream is a segment of a warm surface current that flows north up the entire length of the Atlantic, all the way to Norway and Greenland. There the water cools and sinks, and begins a long journey south on the Atlantic ocean floor, to the Cape of Good Hope and then east towards Australia, and even into the Pacific, where the water upwells and rejoins the surface flow, west to the Atlantic for the long haul north again. The round trip for any given water molecule takes about a thousand years.

      Cooling salty water sinks more easily than fresh water. Trade winds sweep clouds generated in the Gulf of Mexico west over Central America to dump their rain in the Pacific, leaving the remaining water in the Atlantic that much saltier. So the cooling water in the North Atlantic sinks well, aiding the power of the Gulf Stream. If the surface of the North Atlantic were to become rapidly fresher, it would not sink so well when it cooled, and that could stall the conveyor belt. The Gulf Stream would have nowhere to go, and would slow down, and sink farther south. Weather everywhere would change, becoming windier and drier in the northern hemisphere, and colder in places, especially in Europe.

      The sudden desalination of the North Atlantic might seem an unlikely occurrence, but it has happened before. At the end of the last Ice Age, for instance, vast shallow lakes were created by the melting of the polar ice cap. Eventually these lakes broke through their ice dams and poured off into the oceans. The Canadian shield still sports the scars from three or four of these cataclysmic floods; one flowed down the Mississippi, one the Hudson, one the St Lawrence.

      These flows apparently stalled the world ocean conveyor belt current, and the climate of the whole world changed as a result, sometimes in as little as three years.

       Now, would the Arctic sea ice, breaking into bergs and flowing south past Greenland, dump enough fresh water into the North Atlantic to stall the Gulf Stream again?

      Frank Vanderwal kept track of climate news as a sort of morbid hobby. His friend Kenzo Hayakawa, an old climbing partner and grad school housemate, had spent time at the National Oceanic and Atmospheric Administration before coming to NSF to work with the weather crowd on the ninth floor, and so Frank occasionally checked in with him, to say hi and find out the latest. Things were getting wild out there; extreme weather events were touching down all over the world, the violent, short-termed ones almost daily, the chronic problem situations piling one on the next, so that never were they entirely clear of one or another of them. The Hyperniño, severe drought in India and Peru, lightning fires perpetual in Malaysia; then on the daily scale, a typhoon destroying most of Mindanao,