Yeb Sano was a longtime environment activist, working for many years with conservation group WWF before joining Philippine government service as a climate change commissioner in 2010
After a high-profile stint as the Philippines' top climate envoy, demanding world powers do more to fight global warming, Yeb Sano is embarking on an epic pilgrimage to force change.
Sano will this weekend begin a global odyssey to places vulnerable to climate change, starting with the cyclone-devastated Pacific island nation of Vanuatu and Australia's Great Barrier Reef.
He is leading a "People's Pilgrimage", culminating in a 60-day trek to Paris for a United Nations summit in December when world leaders will attempt to forge a new treaty aimed at limiting global warming and preventing its catastrophic consequences.
Backed by interfaith and environment groups worldwide, Sano is hoping the grassroots movement will see thousands of people join him for the final stage of his walk into Paris in a show of moral force.
"We are going to send a powerful, loud message to world leaders that we are many, and we care about the governments and industries of the world finding a solution to the climate crisis," Sano told AFP this week as he prepared to depart his home city of Manila for the pilgrimage.
"What we want is a just, equitable, ambitious and durable climate agreement to be forged in Paris."
- 'Climate madness' -
Sano, quietly spoken but charismatic, emerged as a star for many in the global environment movement with a spectacular display of diplomacy at the 2013 edition of the annual UN climate summit.
As lead negotiator for the Philippines, and with Super Typhoon Haiyan having just killed thousands of his countrymen, Sano made a tearful demand for world leaders to take fast and firm action against global warming.
"What my country is going through as a result of this extreme climate event is madness. The climate crisis is madness," Sano told his fellow delegates gathered in the Polish capital.
Sano then endured a water-and-tea-only fast for the 14 days of talks in Warsaw in an ultimately futile effort to pressure delegates into making bold decisions to contain climate change.
Sano was a longtime environment activist, working for many years with conservation group WWF before joining government service as a climate change commissioner in 2010.
He quit in April this year to return to grassroots campaigning and lead the People's Pilgrimage.
This came after the Philippine government, eager to be seen as less confrontational in the UN negotiations, excluded him from last year's summit in Peru.
- People power -
Without commenting on his controversial omission, Sano said he quit because he believed he could do more to effect change from outside the negotiation rooms.
"I've always considered myself as part of the people's movement. And it's logical for me to go back to my roots," said Sano, 40, who is married to a lawyer with two children.
Even while still in government, Sano walked 1,000 kilometres (630 miles) from Manila to Tacloban, his father's home town and the city worst-hit by Haiyan, for the one-year anniversary of the devastating typhoon.
Sano said this experience, when he was able to reflect on climate change and engage with local communities who endure frequent typhoons, spurred him into embarking on the People's Pilgrimage.
It is organised by OurVoices, a global faith-based organisation campaigning for climate change action, and backed by major environment groups such as Nobel laureate Al Gore's The Climate Reality Project.
Over the next six months Sano will travel to Africa, the United States, Asia and Europe, doing mostly small walks and encouraging others to do the same in what he believes will help build pressure ahead of the Paris summit.
The highest-profile event will be the more-than-1,000-kilometre walk from Rome to Paris to coincide with the start of the UN summit.
The pilgrimage envisions other groups doing similar treks from other parts of Europe or the world, with tens of thousands meeting up in Paris and converging on the summit venue together.
"The image of people walking together, especially when we mass up and arrive in Paris, we hope that can provide the inspiration and the important political push for world leaders," Sano said.
Using open-sourced Internet tactics to gain traction, anyone can register and promote their pilgrimage, big or small, at www.peoplespilgrimage.org.
In Paris, world leaders are meant to seal a pact that would curb greenhouse gas emissions and limit global warming to two degrees Celsius (3.6 degrees Fahrenheit) over pre-industrial levels.
Scientists warn that if global warming exceeds that level, catastrophic events like Super Typhoon Haiyan will be the new normal.
But, after years inside the UN process, Sano said he believed the real power to save the world from the worst impacts of climate change was not at the government level.
"We want governments to be part of this new era of cooperation," he said.
"But if they refuse to be part of this, there is a lot of hope in our hearts that we can still do this because the power to change is in the hands of people."