Hi there, and welcome aboard. We’re going to be doing some causality violating here in our time machine, so please keep all your fingers inside the time machine so we don't cause any intentional paradoxes. Are we ready? Let’s make the jump.
It’s late summer, in the late Middle Ages. It could be any late summer between 1278 and 1438 but for sake of arguing, let’s go with late summer, 1311. I picked this particular year because, as it happens, it’s the beginning of the end of the much researched Medieval Warm Period and the beginning of the much researched Little Ice Age---both of which had very significant impacts on all of human civilization, planetwide. Perfect time for an unusual weather pattern to set itself up.
We’re flying over what will eventually become the US East Coast. Now we’re going to set our time machine to hover at the location that will become Nieu Amsterdam, and then, New York City.
It’s quite nice. There’s no buildings. Look at the marshes! Hey check it out, herons! Beaches are unspoiled---save the handful of native encampments. We notice that they’re deserted. Why?
There’s a hurricane coming. Don’t worry—we’re safe in our time machine, as it runs on magic. It’ll protect us from this hurricane, which makes a rare landfall along the New Jersey coast at high tide.
This hurricane, believed to be one of exceptional intensity --at least a Category 3 and very likely stronger, will leave its mark on the future New Jersey and New York coastlines, leaving a telltale signal in the sedimentary record of marshes in southern New England as well. Islands are completely overtopped and this sand and other debris is deposited in the marshes and back bays like Egg Harbor Bay, Jamaica Bay, and other locations along Long Island to wait for future geologists to excavate, to tell the story of this monster storm. Large portions of what will become the future Manhattan are flooded with its storm surge. Thirty feet of water covers the future location of JFK. Trees down. Coasts flooded up to a mile inland. But luckily, the human toll is nil to none.
We’ve seen what we need to see, so we’re going to jump ahead in time 510 years. Fingers inside the time machine!
It’s 1821. We’re watching ships sail through the Verrazano Narrows and up the Hudson. Up ahead, New York sits at the end of Manhattan Island. The city has only begun to grow.
It’s September 3rd, so it’s getting pretty stormy. Two days prior, a very intense hurricane made landfall along the North Carolina coast near Wilmington. It was at least a Category 4, and perhaps a Category 5.
The cyclone will maintain its strength as it skirts the coast, speeding up to a forward motion of at least 35 miles an hour. It will strike New York City at low tide as a Category three hurricane, but its winds and strength will have the same result as our 1311 hurricane. Lower Manhattan will flood completely—everything below Canal Street becoming part of New York Bay. The surge at the Battery is a record that won’t be broken for another 191 years. The storm leaves its signal in the sedimentary record again, from sand and debris pushed into the marshes along Long Island and New Jersey.
The storm will have a prodigious effect on science. Meteorologists of the time will note that hurricanes are cyclonic storms, with winds that rotate around a center, simply from observing the many millions of trees the hurricane blew down across Connecticut and Massachusetts as it moved inland.
We’re jumping ahead in time again, 72 years. Tray tables up, please!
It’s August 23th, and it’s stormy again. Another hurricane is approaching. And New York City and its environs are considerably more built up.
This storm is weaker than the two we’ve seen via our time machine. Its eye comes ashore near the future location of JFK (It’s 1893, and there are no airplanes.) Storm surge flooding is significant—and prophetic for events to come 119 years in the future. Waterfront neighborhoods in Brooklyn have waist-high water in the streets, and Coney Island is inundated up to 200 yards from the shore. The city is essentially cut off from the outside world for a short time, as telegraph wires cannot handle the high winds.
During the night of the 23rd, the storm surge also floods, and then destroys, an entire island.
Just south of the Rockaways sat an island called Hog Island. The island was not a permanent feature---no barrier island really is. Local lore stated the island appeared after the Civil War, built from sand and sediment moving west along the shore. It eventually grew to be a mile long and 200 feet wide. People in the Rockaways learned their beachfront property was no longer beach front. There were lawsuits.
Developers practically ran each other down to build a resort on the island, and the resort eventually became the part of the Tammany Hall political machine.
During the hurricane, its intensity assessed at Category 1, the island and its resorts vanished from the Earth. Over the next century debris will wash ashore or be placed there during beach replenishment projects—china plates, silverware, cups, saucers, bits of wood, bottles, and furniture, unearthed from the seabed by waves and currents and dredging machines.
We’ve seen what we need to see although we won’t leave 1893 without noting that three days after this hurricane, another one of significant intensity will strike near Savannah, GA, killing thousands along the islands. Both of these hurricanes are generally forgotten today.
We jump into the future—our present, where we know what Hurricane Sandy did. The New York of 2012 has millions more in harm’s way compared to the New York of 1893. Sandy and the exceptionally intense extratropical storm it became just before landfall struck New Jersey at high tide, and during a spring tide, pushing a surge of 14 feet or more above mean low water into points north of its landfall, including New York Harbor.
Thank you for time traveling with us.
Now, you may ask why we took this trip through time. It was to show a number of things: Sandy was not the worst case event. It was not a one hundred year event. Based on history it wasn’t even extreme. But, climate change will make things worse, with possible more intense hurricanes, especially as the seas rise through the rest of this century. And even if we made efforts to create a zero emission society today, this very second, we’ll be stuck with a warming climate until at least 2060. That may well mean more Sandys for the next half century, or far, far worse, no matter WHAT we do now, this very second.
And more 1893s. Remember, barrier islands are not permanent geologic features. And the seas are rising.
And more 1821s, which is still the last major hurricane to have its eye pass directly over New York City. That it struck at low tide is probably why New York City still exists. A high-tide storm would have flooded much of the city’s original Manhattan footprint to a depth of several tens of feet. It would have been washed away like Galveston was, 79 years later (almost to the week.)
And more “1311s”, which is a storm that still is likely unparalleled by anything we’ve seen to date and we only know about its occurrence because coastal geologists accidentally discovered its presence in the sediment record.
New Yorkers, even with this new and changing climate regime, you did not just survive the Big One. Sandy was no superstorm. That day and those storms are still coming, and climate change will make it worse than the three examples I’ve pulled from history and prehistory.
I’m not that hopeful for the future. As FishoutOfWater reports , IPCC5 in Doha will either ignore or not give much attention to melting permafrost. The methane released from this will cause even more heating in the Arctic, which is now warmer than it was when the Vikings discovered a few green tendrils of fjord in southern Greenland. It becomes compound then. More heat begets more heat globally. And then more heat. My point stands; even if we stopped emitting GHGs now, the Earth will continue to warm significantly.
Setting a target of 2 degrees C is what we need to do, by reducing emissions. That will protect the planet post-2050. But what we also need to do is really start building resiliency. This is probably the toughest part of all.
Recall when the arguments over rebuilding New Orleans began, post-Katrina. New Orleans, as we all know, sits at or below sea level, due to the compaction of marsh soil because of water extraction and the straight-jacketing of the Mississippi. Will it survive the century?
Now there’s talk of whether places like the Rockaways and Midland Beach and the Jersey Shore should bother rebuilding. Should the shore points of New Jersey rebuild? Should we build storm surge barriers like that of the Thames Barrier near London, or the Dutch Delta Works---since we’ve built on the barriers naturally provided? I don’t know the answer to that.
But there are steps that could be taken, now, to build the resiliency and adaptation we need while, in concert, we stop dumping GHGs into the atmosphere. A sample:
1. When the weather services warn you, and the media actually does a good job conveying those warnings, don’t think back to the storm the previous year (Irene—which did fizzle) and go “well, it fizzled, so this one will too.” Sandy was forecast to strike where it did and at the strength that it did and as the type of system that it was seven days out. The weather is NOT unpredictable. Even now. (I had the opportunity recently to attend a school science fair held here in the Pennsylvania Capitol Building. Third graders tracked the weather for a month, and determined that the forecast was accurate 74% of the time. Stop saying meteorologists are wrong half the time. They so are not!)
2. A very serious effort needs to be made to storm-proof utility lines.
3. We probably can’t easily stop people from rebuilding along the coast, but there are Federal laws in place that can prevent new development. I write often here at Daily Kos about earthquakes--past, present, and future. Seismologists and geophysicists have been saying for some time now that we are in the last great building boom that will ever happen because the population is undergoing the last great doubling that it will ever have. There’s a responsibility to make buildings safe so that they don’t crush their occupants when the ground shakes. Now, there’s a responsibility to ensure more people aren’t in the way of the rising sea. Otherwise, they’re just offerings to the sea as sacrifices.
4. While the best and least-disruptive storm surge barrier plan would not protect ocean-facing locales on Staten Island and Long Island, it would keep a surge from crippling the transportation infrastructure in the inner bays.
5. This is the most important one, but we need to get far better at conceptualizing events that occur on large time scales. 2060 is still decades away; many of the people reading this diary will be very old or dead by that point. I suspect that unfortunate human failure to comprehend long time scales, even those of a century or less, compounded by a pervasive belief in the United States that the world is only 10,000 years old—yeah, I will never, ever let that go---is a huge driver of the disbelief at what is coming.
Very tough decisions are ahead. I don’t think we’ll make the right ones as I am indeed a pessimist now. Prove me wrong. Start demanding we do.