As Earth approaches several catastrophic global warming “tipping points”
January 24, 2018
BY JASON PRAMAS @JASONPRAMAS
Before writing more columns examining Boston city government’s emerging plans to cope with the effects of global warming, I think a quick review of what area residents are likely to face in the coming decades is in order. Because it’s important to disabuse people of the idea that we’re dealing with “just” a handful of significant problems over time—a rise in air temperature, an increase of extreme weather events, and a rise in sea level—that those problems are isolated to just Boston or the United States, that they are going to continue until the end of the century and then stop, and that there are some simple things we can do to prevent those problems from becoming unmanageable.
The reality is far more frightening. According to Mother Jones, “In 2004, John Schellnhuber, distinguished science adviser at the Tyndall Centre for Climate Change Research in the United Kingdom, identified 12 global-warming tipping points, any one of which, if triggered, will likely initiate sudden, catastrophic changes across the planet.”
There’s been much research and debate since that time about which systems can be considered tipping points and which ones need more research before we can be sure, but the Environmental Defense Fund has a page on its website with an overview of the latest science. It’s called “Everything you need to know about climate tipping points” and you should read it in full. But here’s a quick summary of the tipping points that the Earth is passing or on its way to passing. Largely due to humans continuing to burn CO2-producing oil, gas, and coal decades after it was known to be suicidal to do so.
1) Disappearance of Arctic Summer Sea Ice
The poles are warming faster than the rest of the planet. In the Arctic, sea ice has been melting much more quickly than it used to for much more of every year as the average global temperatures rise year after year. Scientists are now predicting ice-free Arctic summers by mid-century. The less of the year that ice covers the Arctic, the less sunlight is reflected back to space. Sunlight that is not reflected warms the Arctic Ocean, leading to other problems and more global warming overall.
2) Melting of the Greenland Ice Sheet
Of particular concern to Bostonians because of our relative proximity to Greenland, the melting of its ice cap may continue for the next few hundred years until there is none left. Unlike melting sea ice that doesn’t add water to the world’s oceans, melting ice from land does. This will ultimately result in global sea level rise of up to 20 feet, and the process is underway.
3) Disintegration of the West Antarctic Ice Sheet
This tipping point may already have been passed—with the West Antarctic ice sheet already starting to collapse. Like the Greenland ice sheet, it too is expected to take hundreds of years to finish melting, but when it does it could raise the global sea level up to 16 feet.
4) Collapse of Coral Reefs
With oceans already warming and becoming more acidic, the algae eaten by the coral that make up the world’s often huge and spectacular reefs is being jettisoned, resulting in coral bleaching. This process weakens the coral and hastens its death. Which is accelerating the destruction of marine spawning and feeding grounds globally with dire consequences for many nations whose economies rely on them—and for biodiversity. Scientists now predict that the remaining coral reefs will collapse before there is rise in the global temperature of 2 degrees from the old normal average. Most climate models show the world reaching that threshold before the end of this century.
Beyond these, there are several other expected tipping points being studied: the disruption of ocean circulation patterns from the massive influx of fresh water from melting ice (especially in the North Atlantic, which would play havoc with Boston’s climate), the release of marine methane hydrates (which would accelerate the global warming already being caused by the CO2 emissions considered the main cause of climate change), ocean anoxia (a process creating growing oxygen-deprived “dead zones” in our oceans that can no longer support most life, aka “bye bye seafood”), the dieback of the Amazon rainforest (caused by human activity like cutting down huge numbers of trees with devastating consequences for biodiversity coupled with the loss of a major CO2 sink), the dieback of the boreal forests (still being studied, but means the death of more vast forests in and around our latitude of the planet), the weakening of the marine carbon pump (the Earth’s oceans have been absorbing much of the excess carbon in the atmosphere, but through this process will become less effective at it), the greening of the Sahara (some positive effects would come from this, but many basic ocean life forms rely on nutrients from the desert sand blowing into the ocean and will be negatively affected by losing it), and the increasingly chaotic Indian summer monsoons (could result in extensive drought in one of the Earth’s most populous regions).
Other processes underway may also be potential tipping points, including the collapse of deep Antarctic ocean circulation, the appearance of an Arctic ozone hole (joining the existing Antarctic ozone hole in causing rising UV levels in the Arctic with various negative effects), the aridification of the US Southwest (as moisture moves to the upper Great Plains), the slowdown of the jet stream (which could leave more weather systems stuck in place for weeks at a time, including extreme systems like our recent polar vortex-induced cold wave, among other negative effects), the melting of the Himalayan glaciers (which help provide fresh water for much of South Asia’s population), a more permanent El Niño state (which could result in more drought in Southeast Asia and elsewhere), permafrost melting (which results in more CO2 and methane being released, accelerating global warming further), and tundra transition to boreal forest (with uncertain effects).
Adding the above to the general effects of global warming that we’re already experiencing—areas that got lots of rain getting less and areas that got little rain getting more rain storms for more of the year, hotter temperatures overall leading to an array of bad effects like tropical diseases moving north, and the “sixth extinction” of large numbers of species of animals and plants—and keeping in mind that this is happening everywhere around the planet, readers should understand that we’re not facing a localized crisis.
And remember, all the processes mentioned above are interlinked in complex ways that are absolutely not fully understood by our current science.
So Boston is not just going to “trial balloon and town hall meeting” its way out of this array of existential crises. Surviving even one of the major problems caused by global warming—like the flooding from rising sea levels I wrote about last week—is going to be very difficult… and very expensive. And who’s going to pay for it? Well, going forward, in addition to pointing out that we’ll have to devote an ever-increasing percentage of public budgets to these problems, expect me to call for the corporations that started and continue to profit from global warming—the oil, gas, and coal companies—to pay for cleaning up the mess they created. To the degree possible. Which might not be sufficient to the monumental tasks at hand.
Still, it will be critical for Boston to join municipalities like New York City in suing the carbon multinationals Exxon, Chevron, BP, Shell, ConocoPhillips, and others for redress. While divesting the city from all investments in those companies’ stocks. And suing, and ultimately deposing, governments like the Trump administration that are aiding and abetting these corporations’ destruction of the planet.
Failing that, Boston and all of human civilization is literally sunk… burned… and perhaps ultimately suffocated. Dying not with the bang of nuclear war—itself a fate we also need to organize immediately to avoid given the federal government’s return to atomic sabre rattling—but with an extended agonizing whimper.
It’s up to all of us to stop that from happening.
Apparent Horizon is syndicated by the Boston Institute for Nonprofit Journalism. Jason Pramas is BINJ’s network director, and executive editor and associate publisher of DigBoston. Copyright 2018 Jason Pramas. Licensed for use by the Boston Institute for Nonprofit Journalism and media outlets in its network.