The devastating effects of global warming are likely to arrive much sooner than previously thought, according to a new report from the United Nations. This is grim news for the whole planet, as many observers have noted, but the report also highlights that some parts of the earth are far more vulnerable than others.

Dangers Just Over the Horizon

The most startling conclusions of the report , which summarizes more than six thousand highly respected scientific studies and was drafted by a panel of noted climate scientists convened by the United Nations , are twofold. First, the world is continuing to heat at an alarming pace: if greenhouse gas emissions continue at the current rate, global temperatures will rise 1.5 degrees Celsius above preindustrial levels by 2040, and then by 3 degrees by 2100. In other words, governments around the world will now have to work incredibly hard to bend the curve and keep global warming well below 2 degrees, which is what they agreed to in Paris in 2015.

Jayanta Dey/Reuters Boys wade through a flooded village on the outskirts of Agartala, India, October 22, 2017. LinkedIn Email Share Share

Second, many of the most destructive consequences of this planetary warming—more storms, floods, fires, droughts, and other extreme weather—will manifest more rapidly than previously thought, at around the 1.5 degree mark. Prior studies had focused on 2 degrees as being a threshold level for the widest repercussions of global warming.

Where It Matters Most

The effects of climate change will not be spread equally. The study reiterates that the regions of the world likely to be hardest hit are “Arctic ecosystems, dryland regions, small island developing nations, and least developed countries.” Indeed, leaders from some of these places had been pushing delegates in Paris to adopt the lower 1.5-degree cap.

For countries such as Bangladesh, Fiji, and the Maldives, climate change is a life or death matter. “We stand on a cliff edge, either we stand united . . . or we all stumble and fall and condemn humanity to a tragic future,” Tuvaluan Prime Minister Enele Sosene Sopoaga told world leaders in Paris in late 2015. “Any further temperature increase will spell the total demise of Tuvalu with all our fundamental rights of survival.”

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Impoverished populations in these low-lying regions face an increasingly uncertain future as rising seas creep into fresh water supplies and destroy what’s left of arid land. For instance, a rise in temperatures beyond 1.5 degrees Celsius could mean that by mid-century more than fifty million people in Bangladesh alone will have to flee their country to survive.

What’s the Fix?

The scientists warned that governments must take drastic action to avoid further warming effects, as climate change is already devastating many localities. The panel asserted that to meet the goals of the Paris accords and reduce other risks, global carbon emissions must decline by 45 percent from 2010 levels by 2030 and reach net zero by 2050.

Global carbon emissions surged to record levels last year, despite international efforts to curb them. Reversing this trend will take unprecedented global action, which in today’s fractured geopolitical setting looks increasingly difficult to achieve.

Call to Action

The new findings are a wake-up call that few countries are moving forward with the comprehensive interventions needed to prevent mass migrations and devastating losses of life and property. Not enough has been done to either mitigate levels of greenhouse gas emissions or prepare for the consequences of not doing so.

The Trump administration appears to be abdicating its superpower role on global carbon mitigation and climate adaptation efforts. “We reiterate that the United States intends to withdraw from the Paris agreement at the earliest opportunity absent the identification of terms that are better for the American people,” the U.S. State Department said following the release of the UN report.

Without bold leadership from industrialized countries such as the United States, the fate of the world’s most vulnerable hangs in the balance.