The U.S. Defense Department regards climate change as a “threat multiplier” that exacerbates existing environmental stresses and national security risks, and affects everything it does.

Recently, scientists connected giant waves in the global jet stream to hot, dry spells gripping widely separated parts of the planet at the same time. Now they have done the same for winter weather.

The renewable energy transition has begun, but it will not happen rapidly. In the meantime, we need to invest in infrastructure and other measures that will enable human settlements to withstand the impact of extreme weather and recover from the damage that inevitably comes.

People are experiencing the climate crisis firsthand, and it is changing their understanding of how the world works. The crisis is real, but so, too, is our determination to address it.

We need a stronger and more resilient built environment to withstand the rains, wind, heat, and cold of climate-accelerated extreme weather events.

We need to build our response capacity leading up to extreme-weather emergencies and implement a more systematic and assured process of reconstruction for victims in the aftermath.

Cynthia Rosenzweig co-chaired the New York City Panel on Climate Change, an expert body advising the mayor, from its inception four years before Hurricane Sandy, and well after. Here, she assesses what was learned, and done, before and after.

Engineer Daniel Zarrilli advised both the Bloomberg and deBlasio administrations in the wake of Hurricane Sandy. He is now a special advisor on sustainability and climate to Columbia University.

A scientist and writer reflects on the links between climate and extreme weather, New York City’s preparedness, and the role of the media in informing the public.

When a weather disaster happens every hundred years, it is an emergency. When it happens every year, it is a routine, periodic occurrence from which we need to protect ourselves.