Climate Change Briefs: Earth Passed Temperature Tipping Point Decades Ago

On engineering carbon-guzzling plants, Alaska’s tsunami risk, greening your laundry and other reports this week

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Past the tipping point for global warming? (Kilauea, illustration)
Past the tipping point for global warming? (Mt. Kilauea, illustration)Credit: U.S. Geological Survey/ AP

“The tipping point is that magic moment when an idea, trend, or social behavior crosses a threshold, tips, and spreads like wildfire.” – Malcolm Gladwell, “The Tipping Point” (2000)

Malcolm Gladwell was writing about viral marketing, not Earth sciences, but a similar principle can apply to global temperatures. Now a new study claims that the planet has passed the tipping point for temperature rise: If we wanted to keep our planet from warming, we would have had to stop emitting greenhouse gases in the 1960s. Maybe the 1970s. It’s moot because we didn’t and warming has become self-perpetuating – likely for centuries to come, according to the paper from Norway published in Nature Scientific Reports. The researchers’ model shows that permafrost melt will continue even if not one more molecule of greenhouse gas is emitted.

The report provoked controversy: Not all agree with its findings, but it is agreed that preserving our planet as we know – knew – it means removing vast amounts of carbon from the atmosphere, which we don’t yet know how to do. Reforestation on a vast scale could help.

It’s a bird, it’s a plane, it’s Superplant?

Or, maybe we can inquire: What is a plant? A recent theoretical proposal by American, Chinese and Israeli scientists to genetically engineer plants, essentially, to “eat” more greenhouse gases is: (a) theoretical, (b) therefore untested, untried and, as pointed out by the University of Nanjing, would be (c) a step into the unknown. “Perturbations of the carbon cycle on a global scale will be profound and irreversible in their consequences,” points out the University of Nanjing. So it sounds interesting but a profound, open risk analysis would be in order. Much the same applies to the notion of geo-engineering the atmosphere to reflect more sunlight – we don’t know how to do it or what effect it might have, but we may have no choice but to find out.

Meanwhile, rather than creating frankenplants, other scientists are combing through the seed vault in Spitsbergen, Norway and gene banks, trawling for genes lost through cultivation that could help plants survive climate change. This effort, using maize, is described in Nature Communications.

As for the controversy about tipping points and the inevitability of more warming, this graph by sea level rise guru John Englander shows the correlation between atmospheric carbon dioxide and temperature. Note the amount of carbon dioxide in our atmosphere to which the global average temperature hasn't yet reacted.

Correlations between atmospheric CO2, global average temperature and sea level rise over the last 400,000 yearsCredit: John Englander

Shrinking glacier puts Alaskans at tsunami risk

A less-considered risk of glacial meltdown is tsunami – when the vanishing ice destabilizes land, leading to a landslide into the sea. In fact the risk posed by Alaska’s Barry Arm Glacier has been in scientists sights’ for some time, but now NASA has provided satellite imagery showing how much the ice river has retreated in just a few years, destabilizing the terrain. The mountainside near the Barry Arm Glacier moved 120 meters (394 feet) between 2010 and 2017. If the mountainside fails the slide will fall a thousand meters into the sea. The impact would trigger a tsunami, plausibly amplified by the structure of the narrow fjord into a mega-tsunami, as happened in 1958 at Alaska’s Lituya Bay. That landslide produced a wave 525 meters (1,700 feet) high.

Barry Arm glacier, 2013Credit: NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. Geological Survey
Barry Arm glacier, 2019Credit: NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. Geological Survey

Why we may need sandbags inland

Apropos mega-waves, another aspect of climate change that science has long been warning about is the fact that storms are not only bigger and meaner: They stay stronger for longer, including after they hit land. As the world warms, hurricanes forming over warm water take in more moisture, and after hitting land may well dissipate more slowly, reaching farther inland, warn Lin Li and Pinaki Chakraborty of the Okinawa Institute of Science and Technology in their Nature paper, “Slower decay of landfalling hurricanes in a warming world”. In other words it won’t be only coastal communities that need to brace when a hurricane approaches landfall.

A river runs beneath it

Moving from plants to ice, there may be a great whopping 1,000-kilometer-long river flowing beneath the Greenland ice sheet. Radar surveys found a valley running down the mega-island’s center, but had suggested the valley was segmented, precluding water flow. That supposed segmentation has been demonstrated to be an artifact. Has the river been found? No. But perhaps we should look harder, because as the paper in the Cryosphere explains, it would affect the hydrology of the Greenland ice sheet, whose melting is key to sea level rise.

New light shed on ugly aspects of fashion

“Fashion is a form of ugliness so intolerable that we have to alter it every six months,” Oscar Wilde quipped. Indeed the fashion industry depends on manipulation of our minds – spike heels come to mind. Now ZME Science offers a must-read feature on environmental damage wreaked by the fashion industry, notably coat hangers – “the plastic straw of the industry.” Among the things we may not realize is how much the industry has boomed and just how much damage it causes, including at the level of microscopic contaminants produced from the start of manufacture to the stage of the washing machine. If you are appalled, Treehugger provides tips on how to green your laundry.

Snag in Europe’s Green Deal

Haaretz always tries to end its climate change briefs on a positive note. A new analysis of Europe’s Green Deal, whose aim is creation of the first “climate neutral” continent by 2050, claims it’s not as effective as one would hope. Why? Because, explain the scientists of Karlsruhe Institute of Technology, the European Union would likely simply “outsource” the environmental damage, through massive imports of food. The EU concepts, including massively planting trees, more organic farming, and more are all good things, but without sustainable trade goals it achieves little for Earth. What can be done? Standards for sustainability must be identified and harmonized – planetwide. What a good thing isolationists lost a major ally this month. And that is the good news.

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