EUREKA - Snowball Earth - page 51

Max, an amiable black Akita, knows the way. He ambles through Paul's outer lab, turns right and
wanders into the office, walks up to where Paul is sitting at his desk, and thrusts his nose into Paul's
hand. Dan stands outside and listens. He can tell Paul's mood by the tone of his grunt.
What follows is usually intense. Dan often ends up staying in Paul's office bouncing ideas back
and forth for one hour, two hours . . . until the early hours of the morning. Sometimes the discussions
become heated, but Dan isn't afraid of Paul. Heated arguments don't bother him much. “Everyone
who's ever worked with Paul really closely has had a catastrophic falling-out with him,” Dan says. “I
know they're all watching me, waiting for the hatchet to fall. And yes, Paul and I fight. I don't just
mean those tongue-lashings—I get those ten times a day. I mean violent, stand-up, screaming fights.
'You are the scum of the earth!' But I don't think I am the scum of the earth, so that's OK. Many's the
time I've vowed never to speak to Paul again. But I keep coming back for more, because I like him.”
“You know why Dan and I work so well together?” Paul often says. “Because friction creates
heat.”
Paul and Dan depend on each other. Though Dan is a professor in his own right, he still loves
getting Paul's attention. He offers his ideas to Paul the way an eager puppy might. Once, when I was
walking down the street with Dan at a conference in Edinburgh, we spotted Paul up ahead. It was late
in the evening, and Paul was strolling hand-in-hand with Erica. Dan raced to catch up with them. As
we all stood rather awkwardly outside Paul's hotel, Dan poured out his latest idea in a torrent of words,
excited, watching all the while for Paul's response. Something to do with how many kilotons of car-
bon are bound up in Paul's carbonate rocks. Erica turned to me, looking amused. “How many kilotons
of this have you had?” she murmured.
And Dan is Paul's conduit to the outside world. He's a Paul antidote. He deals with people
smoothly and easily, soothing the feathers that Paul invariably ruffles. In some ways their relationship
is uneven. Dan has plenty of people he can talk to about his ideas, but Paul doesn't have many friends.
Perhaps because of this, Paul was at least as nervous as Dan about the tenure process. Paul was safe at
Harvard. He was tenured. He could stay as long as he liked. But if Dan hadn't been awarded tenure,
Paul would have lost his closest friend.
Over the months that Dan was being considered for tenure, Paul grew increasingly nervous. He
gave evidence to the committee in Dan's favour. He tried to gauge how the decision might go, and
spent most of decision day pacing up and down the department's corridors. Four minutes after Dan
received the congratulatory phone call, Paul appeared in his office and collapsed on the couch in an
exhausted, relieved heap.
Dan was the perfect person to ask about the Snowball rocks. The key to the story surely lay in
those strange carbonates with their fans and tubes and weird structures. The ones that had somehow
formed in the Snowball's aftermath, when the ice had finally gone. Carbonates come from tropical
oceans, and Dan is an expert in them. He is an oceans-and-carbonates man.
Unlike Paul, Dan doesn't collect his samples from dusty deserts. Instead he tips himself off the
back of a boat, usually in some gorgeous tropical location. The tropics are the Earth's heat engine, Dan
says, because the sun's rays fall most intensely there. They are the key to understanding the Earth's
climate.
Finding climate records from the tropics isn't easy. In polar regions the ice caps are like time cap-
sules. Every year snow falls, and with it come dust and other chemical clues to the climate du jour .
Gradually these layers build up, are buried, and turn into ice. When researchers drill down into the
ice, they can uncover a climate record going back for millennia. In Antarctica, for instance, the ice
cap is so thick that the layers at its base are more than 400,000 years old. There are bubbles of ancient