In 2010, New Jersey climate scientist Alan Robock received a strange call. The Cuban government wanted him to fly to Havana to discuss his research at a conference—initially he was told little else.
Robock had been working on an intriguing question: how scientists could geoengineer the climate to offset the effects of global warming. So he certainly had plenty to say. But it slowly became clear that the Cubans’ all-expense-paid trip hinged on him discussing something else: research with origins dating back to the last gasps of the Cold War.
The Cubans wanted to hear about "nuclear winter," a theory Robock first noodled on in the 1980s. It had postulated that a nuclear war between the superpowers might chill the planet to such a degree that it would doom most of the living things on earth. Over time that theory became more nuanced and the worry over a climatic Armageddon lost traction as nuclear détente brought the arms race to a close. But Robock remained curious. And, in 2006, he began to develop new models based on more current nuclear antagonisms.
The models showed that even a small regional nuclear war could still decrease temperatures around the globe, possibly causing widespread declines in agricultural production. “We don’t have a good name for it yet. We’ve tried to think of something. We don’t wanna call it ‘nuclear spring,’ or ‘nuclear fall.’ We call it ‘nuclear famine’ sometimes.”
These findings were big news, Robock thought. But, unlike in the 1980s, when nuclear winter theorists were greeted with urgent calls from world leaders and invitations to discuss the fate of the planet with the pope, Robock was met with little more than silence. It seemed as if nuclear winter had lost its ability to provoke.
So Robock jumped at the chance to spread the word in Cuba. And the following month he was on his way. Whisked from the VIP lounge at the José Martí International Airport to the Hotel Nacional, Robock was met by a line of Cubans waiting to greet him, one hoping to put an ice-cold mojito in the scientist’s hand. Robock demurred, explaining to the mystified waiter: “I’m supposed to give a talk this afternoon.”
Clearly, Robock thought, Cuba seemed to have an abiding interest in his little corner of the research world. His two-bedroom executive suite looked out past the palm trees to a blue ocean. And later that day Tomás Gutierrez, the head of the Cuban weather service, graciously hosted him for what Robock described as a rather fancy lunch. It was only after Gutierrez received a phone call that Robock learned how the Cubans had stumbled onto his nuclear winter research.
“Sí, sí. Momentito,” Gutierrez said, and then reached for Robock. “Do you mind if the Comandante comes to your talk?”
It turned out that Fidel Castro had been trolling the internet while convalescing after an illness. “He has spare time on his hands he never thought he’d have in his life. And somehow, he discovered my work on nuclear winter,” said Robock. The scenarios that Robock postulated had made Castro quite concerned.
The next day, Robock learned that the venue of the conference had been changed due to sold-out demand. When a black Mercedes deposited him at the Palacio de Convenciones, it seemed to Robock as if every scientist in Havana had been summoned to hear what he had to say.
Up in front, Castro sat nearby, listening intently to Robock’s every word. Then, after Robock’s concluding remarks, Castro spoke, urging the attendees to action in spreading the word. "The whole world needs to know about this," Castro exclaimed, as the state media recorded his edict.
After a photo-op, Robock left the event with a signed copy of Castro’s memoirs under his arm. And, back on the streets, noted Robock, every television seemed tuned to a rebroadcast of his presentation.
Robock says he ended the day celebrating with Castro’s son, Fidelito, drinking aged rum as the Tropicana’s cabaret dancers strolled by.
“The reaction in Cuba was completely different from the reaction I’ve gotten anywhere else. They actually paid attention,” says Robock. “They had a big publicity splash in Cuba."
Castro later wrote about the interaction on his blog as well, urging the world’s nuclear powers to dismantle their arsenals. “So, that was great," said Robock before turning a little glum. Too bad, he added, that Castro “doesn’t have any nuclear weapons to get rid of anymore."
Since then, Robock’s life has turned somewhat quieter again. Few world leaders have come knocking on his door. Reflecting on the problem, Robock concluded, “If you wanna sway the public about this, you need a movie with Julia Roberts—not a professor giving a lecture.”