"It's not sinking!" uncle John is angry. Or grumpy. Or both. He has spent far too much of his life screaming logic at disinterested boobs to tolerate misphrasing. "The water is rising."
The 'it' in question is New York, specifically Manhattan.
"True, but isn't that really a matter of relativity?" I ask. "I mean, if we measure altitude in feet above sea level, then if sea level rises we're technically sinking."
"It's not sinking!" John says. Our Thanksgiving table is filled with relatively agreeable people who agree heartily on the catastrophe of carbon emissions, so in order to stir up a really good fight - an important part of any Thanksgiving - it's important to be stubborn over small details.
John's wife, Susan, interjects "Seattle is rising. The rock bed underneath it is moving the city slowly upward. Venice is sinking. Those have nothing to do with the water level."
These are people who have become so deeply embroiled in a cause that shrugging it off as yet another of the world's moral train wrecks is not an option. To them, global warming is apartheid or imperialism or slavery; anyone who can shrug and a buy an SUV is a collaborator and a villain. They are moral and dedicated people. And, like most moral and dedicated people, they make dreadful cocktail companions.
"True," I say "but look: the kilogram is defined by a block of platinum in Paris, right? So if somebody knocks that block and chips off a few molecules, everything suddenly weighs more. It's the same with sea level."
It's important to keep up these stupid arguments because otherwise John or Susan or both will talk about global warming in earnest.
The problem is that they are too distinguished. John is a scientist emeritus at Wood's Hole Oceanographic Institute and Susan has her own PhD and for ten years was the president of Ecological Engineering, a wastewater management firm. Their titles carry weight, so when they say Manhattan is sinking - or, I suppose, global water levels are rising thus putting Manhattan underwater in a way that, really, has pretty much the same effect as sinking - it's frightening. As if their knowledge didn't scare me enough, they use metric units, which are terrifyingly scientific.
As the only person in the entire world who has not seen An Inconvenient Truth, I can generally avoid confronting the all-but-inevitable implications of global warming if I set my mind to it. Does this winter seem different from the winters fifteen years ago? Sure, but maybe I'm misremembering.
My aunt and uncle know the numbers. When they explain that water levels are rising about 1mm a year but that rate is accelerating, it's mildly frightening. When they explain that, if current trends continue, fifty years from now the next generation - by which they mean me - could easily have a sea level that is one meter higher than the present one, it's depressing. And when they explain that Manhattan would have to spend gobs of money on levies and water pumps or else be partially submerged, I entertain thoughts of doomsday. I like Manhattan. I live there. I would like it to remain an above-water attraction.
If science is the religion of the secular left, then global warming is our Armageddon. And like any young Baptist who believes in the rapture but isn't sure he'll pass muster, I come out of global warming sermons feeling hollow and jumpy.
John is standing now. He rose to refill his wine glass, but he is irritated so standing will do him just fine. "The kilogram's not the same. Water levels change constantly and we don't redefine the heights of mountains. And it's a dumb way to look at it. The water is rising." His tone has a note of finality to it, and he waits for me to challenge him.
Earlier in the night, John noted that his farm is a good 22 feet above sea level (in a rare scientific lapse, he didn't use meters) and thus will mostly avoid the coming flood. Honestly, this seemed smug.
My generation, our generation for those of you twenty-somethings out there, is going to be the first, by most indications, to really feel the worst effects of climate change. We will have memories of polar bears as creatures that lived in the arctic while our children will understand them as yet another in a long list of extinct species. We could easily see large parts of the Greenland ice shelf collapse into the ocean in our lifetimes. And, again, parts of Manhattan - not to mention Florida, Louisiana and Hawaii - will probably be underwater by the time I am in my seventies.
Pessimism is an unpopular sentiment in American politics, even when it seems pretty close to realism. So we won't hear much in this next election about the preposterously large global effort it would take to mitigate, much less reverse, our current climate trends. For the first time in history, China is emitting more carbon dioxide than the United States and India is closing in on us. The candidates will probably talk a fair amount about the US taking leadership in the battle against global warming. They will probably not talk about the fact that to seriously dampen carbon emissions, we will have to convince 2.6 billion people in China and India to develop a transportation system that doesn't rely on automobiles and a fuel system that doesn't rely on petroleum, and that's assuming we can begin to steer our own people in the same direction.
It's not, of course, that catastrophe is inevitable. There is a chance that climate change will occur more slowly. There's a chance that human technology will limit or even eliminate its effects. It's just that there are a lot of very smart people who know a lot about climate change who think we are making the world irreversibly hotter.
John is waiting for me to respond to his point in our tiny argument, and I do: "look, I'm just saying all motion is relative - that's a basic principle of physics - so both sinking cities or rising water levels are correct." It's a dumb point in a dumb argument. At the end of the day, whether the water is rising or we are sinking, we will all still be in deep - and might I add hot - water.