One year ago, I was in Brazil to launch the Brazilian chapter of the United Nations Sustainable Development Solutions Network, an initiative of U.N. Secretary-General Ban Ki-moon. The main message I heard that day was that Sao Paulo was suffering from a mega-drought, but that state and local politicians were keeping it quiet. This is a reality around the world: too many political leaders are ignoring a growing environmental crisis, imperiling their own countries and others.

In the case of Brazil, state and local officials had other things on their mind in 2014: hosting the World Cup soccer tournament in June and July and winning elections later in the year. So they relied on a time-tested political tactic: hide the bad news behind a “feel-good” message.

Some places have been even more foolish than simply ignoring the risks. North Carolina’s coastlands, like coastal areas around the world, are threatened by rising sea levels caused by human-induced climate change. Yet in 2012, land developers convinced the state legislature to bar the use of scientific evidence on rising sea levels in the state’s coastal management policies, at least until 2016. The issue is equally flagrant at the federal level: U.S. Congress members, on the take from Big Oil, simply deny the reality of climate change.

But growing environmental threats are forcing their way into the headlines whether politicians and land developers like it or not. The bad news about mega-droughts and freshwater scarcity stretches from Brazil to California to conflict-ridden countries in the Middle East.

So Paulo’s metropolitan region of 20 million people is now on the verge of water rationing, an unprecedented threat for one of the world’s leading cities. In California, this winter has been another dry season in a bitter four-year drought, one of the most severe in the region’s history. In Pakistan, the minister of water and energy recently declared that, “Under the present situation, in the next six to seven years Pakistan can be a water-starved country.” In Iran, the Hamoun wetlands bordering Afghanistan are disappearing, posing a grave threat to the local population.

Looking back, it is also clear that a decade-long drought in neighboring Syria helped to trigger the unrest that escalated into a catastrophic civil war, with at least 200,000 Syrians dead and no end to the violence in sight. The drought had displaced an estimated 1.5 million people and caused food prices to soar, leading to a spiral of protest, crackdown, and eventually war. Though drought does not explain all of the ensuing violence, it certainly played a role.

Each of these droughts reflects a complex mix of factors: long-term climate change, short-term or decade-long weather patterns, growing populations’ rising demand for freshwater, mismanagement of local resources, and, of course, a lack of political attention and will. Every drought must therefore be confronted locally, addressing local realities.

Yet the global message is also clear: the world’s growing population (now at 7.3 billion, but likely to reach eight billion by 2024 and nine billion by around 2040), human-induced climate change, and the overuse of freshwater for irrigation and urban needs (especially when cities are built up in dry regions) are all fueling the potential for catastrophe.

Recent research indicates that these trends are likely to intensify. Almost all studies of human-induced climate change show that the Mediterranean region, including security hotspots like Libya, Egypt, Israel, Palestine, and Syria, is likely to experience a further significant decline in rainfall, compounding the drying trend that has occurred during the past quarter-century. Likewise, a recent study by my colleagues at Columbia University’s Earth Institute has shown that human-induced climate change is likely to cause increasingly frequent mega-droughts in the American southwest and Great Plains states in the second half of this century.

In September of this year, world leaders will gather at the United Nations to adopt a set of Sustainable Development Goals to address these rising threats. The SDGs will not ensure global action, but, as U.S. President John F. Kennedy once said about U.N. agreements, they can serve as a lever to help move the world toward action. That is why it is so important to start planning for the SDGs now.

Ban launched the SDSN to help countries achieve the new goals. Its key members include universities and think tanks around the world, with leading businesses and NGOs serving as important partners. National and regional SDSN chapters are being formed worldwide, in the Americas, Europe, the Middle East, South Asia, East Asia, Africa, and Oceania. The goal is to ensure strong participation in the SDSN in every country by the time the SDGs are adopted in September.

This spring and summer, in countries around the world, SDSN-affiliated institutions will invite governments to begin brainstorming about how to achieve sustainable development in their cities, countries, and regions. Many politicians, no doubt, will be grateful for the support of their universities, NGOs, and leading businesses. And those who want to hide from reality will find that they no longer can.

That is because our new reality is one of droughts, heat waves, extreme storms, rising sea levels, and unstable climate patterns. Unless we act with foresight and base our actions on scientific evidence, water stress, food insecurity, and social crises will not be far behind. In other words, today’s mounting threats cannot be covered up. The Age of Sustainable Development must be built on openness, participation, and science.

By Jeffrey D. Sachs

Jeffrey D. Sachs is a professor of sustainable development, professor of health policy and management, and director of the Earth Institute at Columbia University. He is also a special adviser to the United Nations secretary-general on the Millennium Development Goals. ― Ed.

(Project Syndicate)