2 Degrees of Separation

2 Degrees of Separation
Outside Boston’s Faneuil Hall, where American revolutionaries first began clamoring for independence in the 1770s, the water is nowhere in sight. Tourists click photos, office workers hurry across the cobblestone paths, and everyone is perfectly dry. As I look around, I try to imagine a different Boston—a Boston of the future, a city that has to fear the ocean.

This is not an easy scene to conjure. The edge of Boston Harbor is several blocks to the east, on the far side of a small green park on a low hill, held back by a seawall of kelp-covered concrete. When I look over the edge at low tide, the water is a good 15 feet below the bulwark. Even at extreme highs, it never reaches the top. Yet the sea level here is slowly but steadily rising. If the trend continues as predicted, ocean waters could climb several feet in the next hundred years.? It would then take only one big storm surge to breach the seawall, just as hurricane Katrina sent floodwaters racing past New Orleans’s levees. Faneuil Hall would be inundated by six feet of water, and Boston would temporarily turn into a series of small island neighborhoods.

Extreme flood risk is just one of many dramatic changes that will come with a warmer planet. The average summer temperature in Boston stands to increase by as much as 14 degrees Fahrenheit by 2100, bringing with it a sharp rise in the number of deadly hot spells. In the 1970s this city experienced only ?one 100-degree day per year. By the 2070s, forecasts call for at least 24 such hellish days annually.