FOROS DE VALE FIGUEIRA, Portugal — Alfredo Sendim was just 8 years old when his family was forced off its 1,100-acre farm in central Portugal amid a wave of nationalizations in the 1970s.
The hard-left policies introduced during Portugal’s tumultuous path to democracy were later reversed, and the Sendim family has since returned to its land an hour’s drive from Lisbon. But in recent years, the now 52-year-old Sendim has grown increasingly worried he might have to leave again, perhaps for good.
This time, it is not a government’s action he fears, but inaction — over climate change.
Last May, Sendim and other plaintiffs from eight countries filed suit against European Union institutions, arguing that the bloc’s emissions cuts were inadequate and had exposed them to the ill effects of climate change. Evidence cited in the case includes devastating fires, record droughts and recurrent flooding.
It is still unclear how far the lawsuit will proceed, but the likelihood of success has never been higher, according to experts and activists. “Legal obstacles once considered insurmountable by many are now coming down one after the other,” said Christoph Bals, policy director with Germanwatch, one of several nongovernmental organizations supporting Sendim’s lawsuit.
Until recently, action on climate change was widely seen as a political issue. But according to Mark Clarke, a partner with the international law firm White & Case, Sendim’s case is part of “a global trend” — a development that adds a legal dimension.
More than 1,300 lawsuits related to climate change, many targeting governments or corporations, have been filed around the world since the 1980s, with a surge in recent years, according to research by Columbia University’s law school and the Arnold & Porter law firm. While judicial systems differ, the various rulings suggest the potential for climate-change litigation to expand and evolve across borders.
If the trend continues, Clarke said, “the volume of such cases alone may drive governments and corporations to take action.”
Most cases citing climate change have been brought in the United States. But courts elsewhere have shown more willingness in recent years to take on the kind of broad lawsuits that would force defendants to adjust emissions targets rather than merely pay compensation.
In 2013, the U.S. Supreme Court indicated its opposition to such challenges when it declined to hear a lawsuit brought by Alaskans against several major U.S. energy firms over climate change attributable to emissions. The justices said it was a political rather than a legal matter.
While courts in Europe have similarly rejected such claims in the past, that changed in 2015 when a Dutch court ruled that the government had breached the European Convention on Human Rights by reducing its emissions requirements more slowly than scientists have deemed necessary. An appeals court upheld the decision last year.
The ripple effects quickly reached as far as the United States.
One suit filed in 2015, Juliana v. United States, is still on track, albeit bumpily, after a judge in Oregon ordered the case to trial in a potentially landmark ruling a year later. The 21 young plaintiffs argue that they have a constitutional right to a clean environment.
The Supreme Court might yet doom their case, but that would not necessarily end large-scale climate-change litigation in the United States. Activists have also turned to state courts, particularly in California, with its tough public-nuisance law. So far, judges have differed on whether state courts are appropriate venues for lawsuits with global implications.
Some recent U.S. lawsuits have also focused on planned projects rather than past liability, paralleling similar efforts in Australia, where in February a judge blocked a proposed midsize coal mine in the state of New South Wales on the grounds that it would contribute to global warming — a legal first in the world’s largest coal exporter.
In a ruling that was front-page news in Australia, the chief judge of the state’s planning court, Brian Preston, agreed with the residents of Gloucester, a town about 150 miles north of Sydney, that the Rocky Hill mine’s potential harm to the climate and the environment outweighed its likely economic benefit.
“What is now urgently needed, in order to meet generally agreed climate targets, is a rapid and deep decrease in greenhouse gas emissions,” Preston wrote.
Legal experts predicted that the ruling would produce copycat cases across the country.
“I think this does send a signal that the legal system is an appropriate place to challenge the ongoing development of fossil fuels,” Will Steffen, a climate scientist who provided pivotal evidence in the case, said in an interview.
While foreign rulings are generally not accepted as precedent by U.S. courts, the parallel rulings in Australia and other countries could still set standards for how to measure a country’s contribution to global warming — a consensus that may then also be followed by U.S. judges.
In 2011, at a legal conference in Hong Kong, Preston became one of the first jurists to advocate using lawsuits to generate political pressure on governments to curtail industries contributing to global warming.
The following year, former Irish president Mary Robinson urged an international meeting of lawyers in Dublin to lead a global effort that would become known as the climate-change justice movement.
Preston was among 19 experts who responded. Their 2014 report, “Achieving Justice and Human Rights in an Era of Climate Disruption,” was a detailed plan for using legal systems to combat global warming.
One key suggestion was to extend well-established human rights laws to cover the harm to individuals from the effects of a hotter climate, including damage to crops, spreading deserts and rising sea levels.
Acknowledging the difficulty of connecting harm done to any individual to a greenhouse gas emitter, the report proposed a wave of new laws around the world giving people the right to sue governments and companies simply for contributing to climate change. It also recommended the creation of a global judicial body, the International Court on the Environment, to enforce climate treaties.
So far, those bold proposals have not become reality.
Standing on a Portuguese hilltop overlooking his tree-covered farmland, which he runs as a cooperative with the help of local families, Alfredo Sendim agreed that global action — along with cross-border legal proceedings — is needed. “We have only one nation. It’s our planet,” he said.
Every year, Sendim said, wildfires have become more frequent in his part of Portugal. In one week last summer, thousands of his grapevines suffered irreversible heat damage amid temperatures never before measured at Herdade do Freixo do Meio, his farm.
He says he has done everything he could to prepare for a drier, hotter future, training his workers to fight fires and adopting water-saving farming methods.
Meanwhile, E.U. member states continue to fall short of their own emissions targets. It is time, he said, for them to do “what they told us they were going to do.”
Patrick reported from Sydney.