Sea Level Rise in New York

Posted by NYPIRG on December 20, 2021 at 8:32 am

This week marks the beginning of winter.  For the next few months, the northern hemisphere will experience its coldest temperatures.  For some, the cold will add to the misery of dark days.  For outdoor winter enthusiasts, the next few months will be their happiest.

Winter brings big snowstorms, most notably in the New York and New England regions, with powerful storms coming up the Atlantic coast known as “Nor’easters.”  These snowstorms generate heavy snowfalls in the northeastern United States.  They also cause the biggest increases in storm surges along the coasts.  These wintertime storms push more water to the coast, raising high tides even higher than normal.

The world’s climate experts have estimated that global mean sea levels rose by nearly eight inches between 1901 and 2018.  Those experts, part of the United Nations’ Intergovernmental Panel on Climate Change, posit that sea levels have risen faster over the last hundred years than any time in the last 3,000 years.

They expect this acceleration to continue.  They estimate an additional 6-9 inches of sea level rise by 2050.  Beyond 2050, however, the amount of sea level rise will largely depend on future greenhouse gas emissions. 

That increase will be felt differently across the globe.  So, while the IPCC report’s projections are for global mean sea level for the year 2100, most coastal locations will experience a sea level rise within plus or minus 20% of the projections.

Here in New York, the state’s coasts have seen a sea level rise of 9 inches in the past century. 

In places like New York City, climate change mitigation measures can be complex because of the city’s location and its extensive network of underground subways.  With more than half of the state’s residents living in the greater New York City area, sea level rise puts people, resources, and the state’s economy at risk.   The state is planning over $4 billion in sea level rise solutions, which include raising roads, fixing drainage, and building seawalls.

And the speed of rise has accelerated over the last ten years and it’s now rising by 1 inch every 7-8 years.  Around Battery Park in Manhattan, it took the sea level 48 years to rise by 6 inches.  Scientists forecast that in just the next 14 years, the sea level will have risen by another 6 inches.

Which brings us back to “Nor’easters.”  As mentioned, those storms are so intense that they drive higher-than-normal sea level rise.  In places like New York City, these tides are typically over a foot and a half higher than normal high tides.  Add that to the increase in sea level due to global warming, and New York is looking at unprecedented flooding.

Higher sea levels create a higher launching point for storm surge.  These seemingly small changes in sea level rise are enough to turn what were 100-year storm surges into much more frequent events.  In fact, in a third of 55 coastal sites studied throughout the U.S., 100-year storm surges will be 10-year or more frequent events by 2050.

In 2012, Hurricane Sandy made landfall and caused $50 billion in damages to the state. Without sea level rise, Hurricane Sandy’s 9.5-foot storm surge would have been lower.  This past August, the remains of Hurricane Henri drenched New York with record-busting torrents of rain.  Little more than a week later, the remnants of Hurricane Ida shattered even those records, causing devastating damage and tragically drowning New Yorkers in their own cars and homes.

Of course, sea level rise and more powerful storms are not the only threats.  Extreme heat is the number one weather-related killer in the United States, responsible for more than 130 deaths in New York City per year, a number that could increase to more than 3,300 deaths annually by 2080 if action is not taken.  Already the number of days reaching 90°F or more is increasing from an average of 18 per year between 1971 and 2000 to as many as 33 days per year by the end of the current decade.  This extreme heat necessitates urgent investments in mitigation and adaptation and will lead to a substantial increase in medical costs, ER visits, and deaths.

Researchers have estimated the potential economic costs of climate change impacts: “Climate change costs in New York State for the sectors analyzed in this report may approach $10 billion annually by mid-century.” 

As Governor Hochul and state lawmakers plan to return to take up policymaking duties next month, it is vital that they continue to ensure that New York leads in the nation in battling climate change and that those most responsible for the world’s damaged planet – the fossil fuel industries – are forced to wind down their business model and to underwrite the costs needed for the state, the nation, and the world to mitigate and adapt to unfolding climate catastrophes.

Let’s make this winter memorable for something other than “Nor’easters” – enhanced climate protections paid for by the oil and gas industries.