A few years ago, when Mary Robinson LL.M. ’68, the former president of Ireland, joined thousands of people marching for action on climate change, she spotted a sign that spoke to her. It read: “Angry Grannies.”

In a recent in-depth conversation at Harvard Law School with Dean Martha Minow, Robinson told the story of how she came to be an “Angry Granny” on the topic of climate change, starting with her discussions with friends and advocates in the most deeply affected communities and leading up to her current mandate as U.N. special envoy on El Niño and climate change. It was all part of a two-day conference, “Climate Change Displacement: Finding Solutions to an Emerging Crisis,” which brought together experts from a range of disciplines and regions to Harvard Law School, to discuss responses at all levels of government.

The conference, organized by the Emmett Environmental Law and Policy Clinic, the International Human Rights Clinic, and the Harvard Immigration and Refugee Clinic, explored governance challenges through the lens of four case studies: Alaska Native villages, some of which urgently need to relocate because of coastal erosion, melting permafrost, and loss of winter sea ice; Boston and other East Coast cities, where rising sea levels are forcing communities to contemplate coastal retreat; Somalia, which is navigating the challenges of internal displacement in a failed state; and Mexico and Central America, where the focus remains cross-border displacement.

In the first of two public events (see video below), Robinson, former U.N. High commissioner for human rights and the current president of the Mary Robinson Foundation — Climate Justice, framed climate change as an “existential threat” that requires a coordinated, inclusive and urgent response. She traced the evolution of that response, from the U.N.’s reluctance in the early ’90s to acknowledge climate change as an issue of concern to the momentum generated by the Paris Agreement, a treaty ratified by 110 states earlier this year.

Robinson stressed the importance of a “bottom-up” approach in crafting policy solutions to climate change and climate change displacement, which is expected to affect millions of people in years to come. She said it was critical to take heed of best practices developed by indigenous communities and others directly affected by the issue, from farmers in Honduras diversifying their crops to villagers in Vietnam sustainably harvesting the fruits of the forest.

She also detailed some of the barriers to progress, such as states’ reluctance to acknowledge the problem, which, combined with a siloed approach to solutions, have damaged the movement overall. But in the face of the challenge, Robinson borrowed words from her friend Archbishop Desmond Tutu, describing herself as a “prisoner of hope.”

Below are excerpts from Robinson’s conversation.

On her own emergence as a leader on climate change:

“Everywhere I went, from about 2003 on, I kept hearing this refrain, ‘Things are so much worse.’ And when I inquired, it was, ‘We can no longer predict the weather. We can no longer know when we would sow and when we would harvest.’ And over and over again, I heard this.

I heard it from Constance Okollet, whom I became a friend of, because she became one of the Climate Wise Women. And she would say that when she was growing up in a village in Uganda they were poor, but they had enough food because they knew when to plant and when to harvest. And she said from about the year 2000 everything changed. They had long periods of drought and then flash flooding and then more drought. It destroyed the school. And she formed a women’s group to fight back, basically.

I heard it in Liberia. I was friendly with Ellen Johnson Sirleaf before she went forth as president. She said that when she was growing up in Liberia, there were two rainy seasons, and they were predictable to a week or less than a week. Now, she said, ‘I don’t know when the rainy season will come. I don’t know for how long. I can’t man my roads.’

It was all over African countries, and of course has intensified since then. And I realized, this was a huge human rights issue.”

On how climate change is forcing entire communities to relocate:

“The key to climate displacement is that climate change—its impacts or responses—have played a substantial role in human mobility. And displacement due to climate change can be either forced, for example, after a terrible cyclone that destroyed a whole village people might have to completely move. Or it can be voluntary if, for example, a farmer feels that she can no longer maintain her livelihood because of severe drought or even severe flooding. So that’s the slow onset.

A friend of mine and a friend of some other people here—Ursula Rakova—is moving her people from her small Carteret Island to Bougainville in Papua, New Guinea. And she talks about it in very emotional terms, in a way, because she says, you know, ‘We negotiated the land. And we’re now negotiating the kind of relationships where 1,500 people are moving, to be new neighbors of the people in Bougainville.’

And she says, then, ‘But there’s nothing I can do about moving from the land of the bones of our ancestors.’ And when an indigenous person says that to you, you know the pain of that—the pain of moving from the land of the bones of your ancestors. So it’s a painful enough process.”

On climate displacement and gender:

There are studies that actually show that women and children are much more vulnerable—women are something like ten times more vulnerable—(and that’s because) when it’s a rapid climate (change)—you know, hurricane or cyclone—they tend to want to protect their children.

On creating momentum to address the human rights implications of climate change:

There are about 40 countries now that have adopted what’s called the Geneva Pledge. It’s a voluntary pledge that arose out of a dinner that the Office of High Commissioner and my foundation organized very strategically last year when the negotiators of what would become the Paris Agreement were in Geneva for the negotiations.

So we brought together at a dinner climate negotiators and their counterparts at the Human Rights Council. And it was actually a great dinner with a great buzz. We had working tables. And then I got up to close it at the end, and I got a note passed up to me that the ambassador of Costa Rica wanted to say something. So I assumed she wanted to thank me, you know, and my office for all the hard work we’d put in and all that.

Not at all. She said, ‘This has been a very important dinner for the governments present. And we want to make a difference now. We need to institutionalize what we’ve talked about. We need to bring our human rights and our climate people together internally, in country, nationally, so that they talk to each other, so that the climate negotiators aren’t afraid of human rights, and so that the human rights people understand the climate perspective on these issues.’

So we drafted a climate pledge. And it’s now adopted by about 40 countries.”

On the Paris Agreement negotiations:

“What was quite extraordinary about Paris—and it really was extraordinary—was that Paris, in that sense of fairness, became much more ambitious than I would have believed this time last year.

I was at a succession of informal ministerial meetings that the French organized where the representatives of Kiribati and Tuvalu and other countries, at huge risk, spoke about the fact, ‘Do we want us to go out of existence? We have to (limit global warming) to 1.5 (degrees Celsius) in the text.’

And in Paris itself, there was what is called the High Ambition Coalition. It was led by the Marshall Islands. I don’t know if you know what size the Marshall Islands are: a small series of atolls, and a population of about probably 50,000 people. And they led. And when they came in arm-in-arm with the United States, with the European Union, it was a moment of great emotion.

And when the gavel came down on the Paris Agreement, I will never forget it, because I’ve been at a lot of these U.N. and other related things. The emotion of the moment was unbelievable. People began by clapping. And the clapping went on and on. And then people started hugging, people started crying. I mean it was just amazing.

And it was because somehow a multilateral process had resulted in something that was more ambitious and fairer for those most affected by climate (change) than anybody thought we were going to get. Doesn’t happen very often.”

On indigenous knowledge and leadership strengthening the movement:

“I was in Chile about two years or so ago, because the president, Michelle Bachelet, had been head of U.N. Women, and she decided to have a big organization for women leaders in Chile. And, prior to that event, we had an opportunity—with the help of UNDP, actually, in Chile—to bring together local groups and listen to them, learn what they were doing locally.

And there were two indigenous women who came. They traveled 11 hours to come, all one night.  They called themselves the guardians of the seeds. And they were actually a huge resource for their whole area in being able to get these seeds propagated, because they had the knowledge. And they were sharing it, and this is what their project was about. It was really very interesting.

There are many, many other examples, but that’s just the one that comes to mind. And I think in climate discussions now, the voice of indigenous peoples is being heard more and more. And in particular, their role in relation to preserving forests. As I mentioned earlier, there was a tendency in talking about forest management, to think of the forest and the ecosystems, and not people. And I think we got over that mistake, and realized that it’s the people who live in the forest and live off the forest who will preserve the forest.”

On what can be done about climate change displacement on the international level:

“I think the general view is that it’s not a case of having a new treaty or a new protection of climate-displaced people, because there isn’t the political will for it. And even if we tried to, it might actually affect the protection of refugees. So it’s a case of working well with the existing treaties that we have and making them link more.

In my foundation, we spend a lot of time working with the Human Rights Council to make it more aware of the negative impacts of climate. And it is very aware. There have been a number of resolutions now. There’s been work at the Office of High Commissioner for Human Rights. There’s an annual resolution now on climate change and human rights.

And then there’s the work of Professor John Knox (U.N. Special Rapporteur on Human Rights and the Environment) on human rights and the environment, and increasingly, climate.

Fortunately, thanks to a lot of hard work, we got much more human rights into the preamble of the Paris treaty. It actually is good at recognizing the rights of indigeneous people; it recognizes that we need to protect a whole range of human rights. And it even mentions climate justice.

On her friend and colleague Archbishop Desmond Tutu’s idea of being a prisoner of hope:

“That’s not just a phrase, it’s actually an extraordinarily important concept, because the trouble is, in the climate context, you can paint a very bleak picture. And all the energy to do something goes out of the room.

Or you can say, ‘It’s difficult. And the glass is not half full. But there are many things we can do.’ And I think that’s the only way we can address it. And that’s all about the hard work of, you know, human solidarity we haven’t shown yet. Because one of the things we have to do, and very rapidly, is get the trillions of investment into developing countries, to help them to grow without emissions, something we didn’t do in the richer parts of the world. We built up our fossil fuel and now we’re trying to reduce.

But if the Chinas and the Indias and the Brazils and South America and the Nigerias—and Nigeria is very difficult at the moment—go that way, then the carbon budget will be exceeded. And they will be the first countries to suffer, but we will all suffer.

You know, it’s a bit like the Titanic. And when it starts to go down, it’s not just those in steerage. It’s also the first class who eventually go under the waves. And so I do think we need to be prisoners of hope and get to work and realize that we have a huge task to have a safe world for future generations and to have a livable world for those who are more vulnerable parts of the world, even now, with the kind of weather shocks that we know are increasing.”

On the future of the movement:

“I think that we all need to recognize that probably the best way to get the message out is to have stories about communities and how they are becoming more resilient, how they are fighting back, what they’ve learned, etcetera. And you know, just make this something that is bottom-up in creating more responsibility. And the further up you go, the more responsibility.

And your generation are so connected, in a way. You know what’s happening in different parts of the world. And I think hopefully that will lead to a real movement for the kind of change we need.”