The Vatican's conference of mayors on climate change and human trafficking has heard sobering testimony from two Mexican women who were victims of modern-day slavery.
Ana Laura Peres Jaimes on Tuesday showed the mayors photos of some of the 600 scars that she suffered as an indentured servant, forced to iron for hours a day without food, water or even a bathroom. She said she had to urinate in a plastic bag.
"We are human beings," she said.
Karla Jacinto, a 22-year-old mother of two, told of how she was forced into prostitution at the age of 12, servicing more than 30 men a day for the next four years until she was rescued.
"I didn't think I was worth anything. I thought I was just an object that was used and thrown away," she told the hushed audience hall.
Jacinto now campaigns on behalf of trafficking victims.
San Francisco Mayor Edwin Lee is taking a cue from Pope Francis, whose nature-loving namesake St. Francis of Assisi is also that of the California city.
Lee announced at a Vatican conference of mayors on Tuesday that the city and county of San Francisco will "completely phase out the use of petroleum diesel" in its municipal fleet of vehicles and replace it with renewable diesel by the end of the year.
"This action will reduce the greenhouse gas emissions from our diesel fleet by over 60 percent," Lee said, to applause.
He added that thanks to federal and state credits, San Francisco's fuel costs will actually be reduced as a result.
The mayor of New Orleans says his coastal city's abundant natural resources are both a blessing and a curse.
The Louisiana city that supplies one-quarter of all the seafood produced in America also provides more oil and gas to the U.S. than Saudi Arabia.
"But that economic benefit comes at a cost," Mayor Mitchell Landrieu told a Vatican conference of mayors fighting global warming Tuesday.
Landrieu recalled the 2010 British Petroleum oil spill, which killed 11 workers and disgorged 4.9 million barrels of oil into the Gulf of Mexico. And he reminded 60 of his fellow mayors of the devastation of Hurricane Katrina, which killed 1,800 people in 2005 and exposed how the city's poorest neighborhoods were vulnerable to sea surges.
"We became a warning to all others that neglect and environmental degradation has consequences," Landrieu said.
The mayor of Kochi, India, is intimately familiar with the intertwined scourges of global warming and human slavery.
Speaking at a Vatican conference Tuesday on the exploitation of Earth and its most vulnerable people, mayor Toni Chammany said the projected rise in sea levels as a result of global warming "is going to pose a big threat to the very survival of the city," which lies only a few feet (less than 2 meters) above sea level.
As a whole, India is expecting another drought year, meaning more and more farmers will leave their land for the cities "pushing them into the dark dungeons of slavery," he said.
Chammany said, because of India's caste system, the country already knows "one of the worst forms of slavery known to man."
Pope Francis called the Vatican summit of mayors to put global warming and human slavery at the top of their national leaders' agendas.
French President Francois Hollande is calling for an ambitious accord on climate to address the threat of global warming.
Hollande isn't at the Vatican climate conference, but he made the call Tuesday at a Paris conference of religious and political leaders.
Halfway through the year, 47 countries -out of 195 members of U.N. climate talks- have presented their emissions reduction targets, including the world's top polluters, the U.S. and China.
Hollande warned that these targets are not sufficient to meet the goal of limiting global warming to 2 degrees Celsius by the end of the century.
The mayor of Stockholm says climate negotiators at Paris talks later this year must "exclude fossil fuels" as an option and focus on long-term sustainable energy sources.
Mayor Karin Wanngaard says she had "great expectations" for the outcome but also was fully aware of the challenges. Stockholm is one of the world's leaders in using renewable energy sources: 75 percent of the city's public transport network runs on renewable energy. Wanngaard's goal is to make the Swedish capital fossil fuel-free by 2040.
"Climate negotiators must dare to push boundaries and exclude fossil fuels as an option and reward solutions that are long-term sustainable and recyclable," she told a Vatican conference on climate Tuesday.
Mayor Bill de Blasio has announced new greenhouse gas emissions targets for the Big Apple at a Vatican summit aimed at keeping up the pressure on national leaders ahead of climate talks in Paris later this year.
De Blasio is a founding member of an alliance of cities around the world that have committed to reducing their emissions by 80 percent by 2050 or sooner.
At the Vatican conference Tuesday, De Blasio said New York was taking an interim step, committing to reducing its emissions by 40 percent by 2030.
"The Paris summit is just months away," De Blasio said. "We need to see it as the finish line of a sprint, and take every local action we can in the coming months to maximize the chance that our national governments will act boldly."
The governor of California is denouncing global warming deniers who are "bamboozling" the public with propaganda and putting "troglodytes" into office rather than environmentally responsible leaders.
Gov. Jerry Brown was one of the keynote speakers Tuesday at a conference of eco-friendly mayors at the Vatican. California has enacted the toughest greenhouse gas emissions standards in North America.
To rousing applause, Brown denounced the "fierce opposition and blind inertia" in the U.S. by climate skeptics who he says are seeking to "falsify the scientific record" and convince politicians, scientists and the general public that global warming isn't happening.
Brown, a former Jesuit seminarian, urged the mayors to not be complacent in opposing them. He said climate deniers are spending "billions on trying to keep from office people such as yourselves and elect troglodytes and other deniers of the obvious science."
The mayors are expected to sign a Vatican declaration urging world leaders to take bold action at Paris climate talks this December.
Environmentally friendly mayors from around the world are gathering at the Vatican for a two-day conference rallying momentum ahead of Paris climate negotiations later this year.
Pope Francis is expected to address the meeting later Tuesday. He's a new hero to the environmental movement, thanks to his recent encyclical denouncing the world's fossil fuel-based economy that he says exploits the poor and destroys the Earth.
The mayors are expected to sign a declaration at the end of the day demanding that their national leaders approve a "bold climate agreement" at Paris talks in December that keeps global warming at a safe limit for humanity.
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