The Thwaites Glacier and You, Part 2
10/13/22 – Sea level rise is here now
As always, please remember to scroll past the end of the essay to read some curated Anthropocene news.
Now on to this week’s writing:
There is, in Antarctica, an aesthetic tension between a landscape of extraordinarily delicate beauty and a climate that can kill you. The sky is wide, the ice and snow are infused with light, and clouds pass overhead like mirrors, but at -30°F with a brisk wind it can be hard to appreciate the splendor.
Much of Antarctica, too, is made up of the featureless ice caps stretching for hundreds of miles. (Next time you’re on a commercial flight above the clouds, imagine stepping out and setting up camp on that gray/white surface; it’s like that.) I loved it, but that love requires a patient appreciation of emptiness. The coast, on the other hand, with its charismatic penguins and icebergs that dominate our image of the Antarctic, is easy to love but represents only a small fraction of the continent.
Once, for just a few days, I visited a place that felt like a perfect synthesis of Antarctic aesthetics. The Ford Ranges, in West Antarctica, are about five hundred miles away from the Thwaites Glacier, which as I discussed last week will be pushing a whole lot of ocean into our lives and the lives of our descendants. But standing atop a nunatak (the peak of an ice-drowned mountain) in the Ford Ranges twenty years ago, I marveled at the subtle beauty of a scattering of peaks emerging from the rolling topography of the ice sheet as cloud shadows played across the scene like birds flying over swimmers in a white sea. It was a stunning composition of very real mountain fragments amid the abstraction of ice. (And it was a balmy, comfy 20°F.)
The image above is of a Ford Ranges nunatak under a grayer sky, but I offer it here to convey the power of the landscape (for scale, zoom in on the people atop the peak) and to provide a visual of some ice that, amid a global catastrophe, may head our way.
There is another aesthetic tension inherent in Antarctica, one between the astounding solidity of a continental ice sheet and its fragility in a warming world. Ice, for all its heft, is just frozen water, and in the Anthropocene we’re rapidly transitioning to a world unfriendly to ice. It grieves me to imagine the disappearance of West Antarctic ice I’ve known – though there’s so much more to grieve right here at home – because I spent years enthralled by a landscape composed of an ephemeral substance that I’d rather not lose to the mere hubris and ignorance of a short-sighted civilization.
There are two curiosities worth pointing out in the relationship between this civilization and the inevitable Anthropocene collapse of the West Antarctic ice sheet (WAIS). First, the bulk of West Antarctica is the only remaining major unclaimed territory on Earth. The region, as the planet’s last marine ice sheet, is a relic of the last ice age in the same way it is, as a terra nullius, a relic of pre-human Earth history when life existed in a place rather than on a map.
Second, one of the more enlightened events of the 20th century was the writing of the Antarctic Treaty (in the depths of the Cold War, no less), which set aside the entire continent for scientific study. There’s an irony in this, as Antarctica is being partially unraveled by the application of 19th and 20th century science – from the internal combustion engine to petrochemical fertilizers to plastics production – even as 21st century science is studying the unraveling.
I have to confess that it’s taken me a while to take sea level rise seriously. Amidst all the acute problems of species loss, petrochemical pollution, a warming atmosphere, and an acidifying ocean, etc., it’s felt odd to me that three millimeters per year of rising seas somehow became a scary poster child for the climate-warped Anthropocene.
It’s hard enough to persuade people who are busy with daily survival, while being fed a steady diet of fossil-fuel disinformation, to transform their lives on the basis of data describing one or two degrees of global temperature rise. Convincing them to fret about their property values because of distant glaciers and their barely-discernible additions to the oceans over the next hundred years hasn’t seemed like a winning argument. Of course I have been conscious of the near-term serious impacts of even a few inches on low-lying communities, including island nations, but the litany of global environmental crises that felt more pressing was long.
I know now, though, that my resistance to sea level rise as a priority issue has been rooted in an ignorance of how quickly things will change, how inevitable that change is, and how dire the consequences will be. It’s still true that forests are burning and falling as I write this, while another foot of sea level rise is thirty years away, but forests can be protected and replanted far more easily than a salt marsh can be relocated or Hong Kong’s infrastructure can be shielded forever from a relentlessly rising ocean.
Like global warming, sea level rise is not merely awaiting us. It’s here now. Oceans have risen, on average, 10-12 inches over the last one hundred years, and are forecast to rise another foot by 2050. The process has accelerated and will continue to accelerate, given a warming climate and the increasing ice loss from Antarctica, Greenland, and the world’s remaining mountain glaciers. The emissions we’ve already committed to promise at least two feet by 2100, while a failure to curb emissions could lead to as much as seven feet in the same time frame.
If you’re looking for an excellent explanation and overview of sea level rise, dig into this Climate.gov page. For now, though, here’s a quick summary of the process. In the simplest terms, sea level rise has two main causes: the melting of terrestrial ice and the increase in the oceans’ volume because of heat. The oceans will continue to expand as they absorb most of the additional heat we put into the atmosphere, and as they collect the liquid remains of the world’s ice. There’s a third, much smaller, contribution to sea level rise I did not know about until researching this piece: the water we pump out of the ground, if not returned back to the ground, either enters the atmosphere as vapor or joins streams and rivers on their seaward path.
Because the Earth is a dynamic place, sea level rise varies from place to place (you can see this illustrated perfectly on this NOAA map here). In some areas sea level is actually dropping, though overall seas are rising. The variation has several causes, ranging from a difference in water temperatures (thus more or less expansion) to a difference in how continents are responding to the retreat of ice sheets thousands of years ago. New England, for example, is still rebounding upward while mid-Atlantic coastlines are settling downward, which has meant that over the last century waters have risen only six inches in Maine, but a foot in New York City, and a foot and a half in Chesapeake Bay.
There are some other interesting nuances: Other causes of variation in measured sea level rise include sinking of the land due to earthquakes or human extraction of water and fossil fuels, the force of the Earth’s rotation pushing water higher in some areas than others, and vertical movement in the liquid mantle below the Earth’s crust. And finally, as the Antarctic ice sheet diminishes in size, it also loses some of its local gravitational pull, which means that seas will rise noticeably higher in the northern hemisphere than in the southern hemisphere.
So where is the Thwaites, the so-called “Doomsday Glacier,” in all this? Well, to be honest, the Thwaites isn’t exactly the lurking beast the media has described. Yes, the Thwaites (and the Pine Island Glacier next door) are losing ice and retreating faster than at any time in the last 5000 years, and yes, the Thwaites ice shelf (which slows the glacier) may collapse in the next five years. Yes, two feet of sea level rise await us in the Thwaites, which now has a net loss of 50 billion tons of ice each year. Most frightening of all, if the Thwaites collapses, the WAIS and much of its 11 feet of sea level rise seem likely to follow on its heels.
Currently, though, global sea level rise is about 3 mm per year, and the Thwaites is estimated to contribute only 4% of those 3 mm. And current estimates for the timeline of a Thwaites and WAIS collapse is measured in centuries, not years or decades. With every new study, we learn more about Thwaites' vulnerability, and of course every estimate of sea level rise, like every estimate of atmospheric warming, has so far been conservative, so a shorter timeline is possible, but from a practical perspective the “Doomsday” label has been misleading.
Our focus should be on the 96% of sea level rise that the Thwaites has come to symbolize. Certainly the Thwaites is the key that will eventually unlock several feet of rise from WAIS, and as such has become a symbol of the global meltdown which poses an existential threat to much of our familiar world. But the importance of the Thwaites is in its future impact on a world that, if we’re being honest, we can scarcely imagine.
Who among us knows what human societies and natural communities, both scarred by our failures and buoyed by our successes, will look like 200 years from now, when the WAIS is pouring millennia of ice into the sea? The map I shared last week of the WAIS subglacial surface is also a map of an accelerating human crisis, but that acceleration is still on a timeframe beyond our current concerns. We must focus on leaving fossil fuels in the ground, immediately reducing greenhouse gas emissions, and generally rebuilding a world that sustains glaciers.
Because if we’re not sustaining glaciers, we’re not sustaining life on Earth as we know it.
For some great visualizations of sea level rise, check out the NOAA Sea Level Rise Viewer for U.S. locations, and look at Climate Central’s three multimedia options (Picturing Our Future, Coastal Risk Screening Tool, and the Surging Seas Risk Finder) for locations around the world. And take a deep dive into NOAA’s Ocean Services Sea Level Rise Technical Report if you want the data.
Next week I’ll partake in some of the usual sea level discussion regarding its unavoidable impacts on our lives and on the infrastructure of an unprepared civilization, but I’ll also take a close look at what rising seas mean for the rest of life. We must remember that we are not alone on this planet. Not yet, anyway.
Thanks for sticking with me.
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In other Anthropocene news:
From The Revelator, an important explainer article on how reforming elections with ranked-choice voting and approval voting may be vital to electing candidates with a focus on the environment.
Also from The Revelator, a rush by conservation groups to purchase and protect land that the Boy Scouts are selling off to pay into the $2.5 billion compensation fund for the organization’s sexual abuse victims.
From Noema, “Who Gave the Battery Such Power?,” a thoughtful investigation into the tension between the fight against climate change and the huge push for the destructive mining deemed necessary to build the batteries required for an electrified civilization. As the article asks, “Should a mine be built upstream from your water source if it means preventing global temperatures from rising 1.5 degrees above preindustrial temperatures?”
From DW news, an excellent brief explainer on the importance of methane in the climate crisis.
From Yale e360, an unsurprisingly dim assessment of massive tree-planting and forest-planting efforts. The frequent failures of these plantings do nothing to absorb CO2, provide false hope in the marketplace of ideas, and are generally more of an obstacle than a solution. Of course replanting forests and restoring habitats must take place, and must occur on a large scale, but they must be done under the guidance of ecologists rather than marketing departments.
From Orion and Columbia Journalism Review, the second installment of Deny and Delay: Inside the Climate Disinformation Machine, a series investigating the effects of climate misinformation on democracy.