As science tying disasters to climate change becomes increasingly accurate, victims could seek legal redress for failure to plan for predictable events

By Megan Darby

Hurricane Harvey is wreaking unprecedented damage on Texas. Should city planners, government agencies and businesses have seen it coming? Could they have prevented death and disruption by acting differently?

Increasingly, such questions will be litigated in courtrooms and rely on climate science to answer, three environmental lawyers wrote in the journal Nature on Monday.

Advances in the science of linking weather extremes to global warming has the potential to change the legal landscape, they write. The more clearly scientists can demonstrate an event was foreseeable, the more victims can – and will – seek redress from negligent authorities.

“In a world where events like Hurricane Harvey are predicted to increase, and predicted confidently by scientists… courts will be called upon more and more to disentangle these issues,” co-author Sophie Marjanac, an Australian-qualified lawyer with Client Earth, told Climate Home.

Marjanac give examples of potential targets for lawsuits. In Houston, Texas, developers were allowed to build on wetlands that otherwise would have helped to drain floodwaters. If it can be shown those decisions endangered people and property – and failed to anticipate known climate risks – the relevant authorities could be on the hook for payouts, she said.

Then there are businesses. At least 10 oil refineries along Texas’ gulf coast have reportedly been forced offline by flooding. Marjanac said they could be liable for any environmental damage resulting from taking inadequate precautions, or face wrangles with insurers.

Such legal cases would hinge on attribution science: studies showing that climate change was at least partially to blame for the damages.

In the article, Marjanac and her coauthors wrote: “Claims are likely to arise when those actors fail to share or disclose relevant knowledge, or fail to take adaptation actions that would have protected those to whom they owed a duty of care. Such litigation may become an important driver of both mitigation of greenhouse gas emissions and adaptive action by both public and private sectors.”

Several climate scientists have confidently asserted that climate change worsened Harvey’s impact, based on observations and physical principles.

Lawyers prefer to have an event-specific attribution analysis, Marjanac said. The usual approach is to model how likely the event would have been to happen in the absence of greenhouse gas emissions and deforestation, then compare it with reality.

For example, World Weather Attribution established that torrential rains in Louisiana last August were made twice as likely by human activity. The coalition of scientists is considering whether it can undertake a similar analysis of the flooding brought by Harvey.

Friederike Otto, a lead proponent of this research from the University of Oxford, explained in a Climate Home article that tropical storms are more complex to model than simple heat or rainfall extremes. In any case, such modelling is expensive to run. But she indicated that even on complex storms, the science was becoming increasingly feasible.

In parallel with efforts to refine the science, others are seeking to bring to light records of the decision-making process.

Ten days before Harvey struck, president Donald Trump issued an executive order revoking rules to make federally funded infrastructure resilient to flooding and sea level rise. While the order was not responsible for Houston’s unregulated growth, it risks increasing the vulnerability of communities to future disasters.

The Center for Biological Diversity filed a request to several federal agencies on Tuesday under the Freedom of Information Act, seeking to unearth factors influencing the decision.

“Harvey’s devastation illustrates the danger of Trump’s order to disregard flood risks to life-sustaining infrastructure on our coasts,” said Shaye Wolf, climate science director at the Center. “With climate change making storms like Harvey more powerful, slashing protections for the safety of millions of Americans in flood-prone areas is just unacceptable.”

A number of high-profile climate lawsuits are already under way.

Seventeen young Americans are suing the federal government for allegedly violating their constitutional rights by failing to adequately address climate change. Their trial is scheduled for February 2018 in Eugene, Oregon.

The New York attorney general is investigating whether Exxon Mobil lied about climate science and thereby misled shareholders about the value of its oil business.

In March, three California coastal communities launched a suit against oil majors, accusing them of knowingly endangering their homes through their business activities.