ISTANBUL — Archbishop Desmond Tutu’s 3-year-old granddaughter, Onalenna, was puzzled.
Her older cousin, Mungi, had just deflated a large, blow-up globe to demonstrate the imminent danger of climate change.
“Are we going to go the moon then?” Onalenna asked her grandfather.
“I don’t know, I will not be here,” Archbishop Tutu, 78, whispered in his granddaughter’s ear.
The rapid march of climate change up the global agenda has prompted a new, and often poignant, conversation between the generations and, in public, among a self-appointed elite.
At its core, that conversation is about whether some of the first beneficiaries of the wonders developed during the past century — like electricity at the flick of a switch — have the means, or the will, to help their descendants with the consequences of burning vast quantities of fossil fuels.
The conversation also is playing itself out across the planet as leaders, industrialists and citizens confront issues too costly for any single nation or generation to tackle alone.
For a group of 20th-century leaders called the Elders — whose members include Archbishop Tutu of South Africa, former President Jimmy Carter and Mary Robinson, a former Irish president — it also was a conversation with their families that they felt would be most usefully conducted before the cameras.
On Thursday, seeking to highlight the responsibility that older generations bear for climate change, members of the group traveled to Istanbul for a symbolic photo shoot accompanied by young relatives.
“This is a rather late wake-up call for all humanity to behave in a more responsible manner,” said Lakhdar Brahimi, 75, a veteran United Nations envoy who helped broker an agreement ending civil war in Lebanon, and who was accompanied by his grandchildren, Balthazar, 5, and Basile, 3. “It is the responsibility of today’s generations to act,” he said.
The Elders group was founded in 2007 with the help of Nelson Mandela. Its chairman, Archbishop Tutu, acknowledged that his generation bore the blame for not making tough choices sooner.
“We should have long ago used recyclable energy,” said Archbishop Tutu, who danced on a lawn as he entertained his grandchildren before the cameras.
“If we had used solar energy or wind power, we wouldn’t have been in this predicament.”
Bjorn Lomborg, a Danish political scientist who found fame as the author of the provocative book “The Skeptical Environmentalist,” said that by campaigning for swift agreement at a global climate conference in December in Copenhagen, the Elders risked backing expensive and ineffective solutions that might divert money from more effective measures to save lives and protect the planet.
“I have no doubt the Elders care deeply about their grandchildren,” Mr. Lomborg said, “but we should be concerned about all the other grandchildren who were not at the event and who run the risk of dying tomorrow from lack of sanitation, starvation and disease.”
Ms. Robinson, 65, said she sympathized with that view, but she added that coming generations would not have a planet to enjoy unless action was taken now to resolve the problem.
“Living in New York, I can see the preoccupation with issues like the health care debate, Afghanistan and Iraq, so it’s difficult to keep the issue on the front burner,” she said. “However, we should make it absolutely clear that it is the supreme political issue of our time.”
The Elders have in the past sought to raise consciousness about conflicts in the Middle East and in Sudan by using their access to high-level figures and staging publicity events.
“We are not restrained by timidity or political niceties or diplomatic propriety,” said Mr. Carter, 85. Many of the Elders praised the virtues of hybrid cars and, paradoxically for such a mobile group, they described advantages of using technology for virtual conferences rather than using airplanes to attend meetings.
Mr. Carter recounted the story of his wearing a sweater during the energy crisis of the 1970s, an act that prompted mockery from critics, who accused him of ineffectiveness in the face of rising energy prices. But from the perspective of a new generation, wearing the sweater looked prescient, he said.
“It got people to register thermostats in their homes and save electricity,” Mr. Carter said. “I never have been very afraid of people making fun. I do what I think is right, and I was right in the end.”