Like Beyoncé, Greenland is constantly making news.
And for good reason. The Arctic landmass holds an ice sheet that's two and a half times the size of sprawling Texas -- and it's melting at rates that are unprecedented in at least centuries, if not thousands of years. "I can tell you the retreat is eye-popping," said Twila Moon, an Arctic researcher at the National Snow and Ice Data Center who has traveled along the vastly diminished ice. For humanity, the particularly salient question now is how quickly these massive stores of ice will melt into the sea.
Greenland's future, of course, depends on the most uncertain, chaotic, and emotionally volatile portion of the climate science equation: humans, specifically how much heat-trapping carbon we decide to pump into the atmosphere. "The biggest uncertainty in climate science is human behavior," NASA scientist Kate Marvel told Mashable after the Trump administration recently said they will no longer consider many climate projections beyond 20 years from now.
But regardless of the federal government's self-imposed limitations, new research, published Wednesday in the journal Science Advances, lays out three clear, potential futures for Greenland:
1.Really bad:A future wherein carbon emissions continue rising as they are now, called the "business as usual" scenario (known as RCP 8.5).
2.Pretty bad:A future wherein emissions moderately rise until around 2050, and then drop substantially -- but not completely -- by century's end (known as RCP 4.5).
3.Not as bad:A future wherein humanity rapidly and immediately slashes carbon emissions today, bringing emissions to zero well before 2100 (known as RCP 2.5).
* This last ambitious future, in line with the historic Paris climate agreement, is now nearly impossible to achieve.
As you might suspect, the new research -- enhanced by NASA's recent aircraft observations of Greenland -- found that the melting land mass (in a rapidly melting Arctic realm) is expected to incur profound ice losses this century and beyond, should carbon emissions continue to saturate the skies (options 1and 2). For reference, carbon dioxide levels in the atmosphere are currently increasing at rates that are unprecedented in both the historic and geologic record.
"We can actually choose how it's going to look."
Yet, humanity has an immediate say in the matter.
"We can actually choose how it's going to look," said Andy Aschwanden, the study's lead author and researcher at the University of Alaska Fairbanks' Geophysical Institute. "The next couple decades are quite important to the future."
"It's going to be worse if we burn more fossil fuels," added NASA's Josh Willis, an oceanographer who leads the science agency's Oceans Melting Greenland mission.
"This has been clear for decades," said Willis, who had no role in the research. "The more CO2 you put into the atmosphere, the more you change the climate."
If emissions continue as they are, by century's end Greenland alone will lose enough ice to boost sea levels by between 5.5 and 13 inches, the research found.
But matters get substantially worse as the centuries progress, adding as much as 12.5 feet by 2300.
Eventually, all the ice would disappear. "We found that the Greenland ice sheet could melt within 1,000 years if we keep adding greenhouse gases to the atmosphere," said Aschwanden. That would raise sea levels by some 23 feet.
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Even if unprecedented steps are taken to curb Earth's warming this century (option 3), Greenland will still experience some melting (adding between 2 and 7 inches of sea level rise this century). That's because there's already substantial warming baked into the absorbent oceans, and the elevated carbon levels already saturating the skies will take hundreds to thousands of years to naturally get soaked into the seas.
"A lot of ice loss has already been baked into the system because of human actions in the past," said Moon.
But that's still a future humanity can adapt to, more so than runaway glacial melting, anyway. "All the effects are worse if we do nothing," noted Willis. "And they're all better if we avoid burning so much fossil fuel."
"All the effects are worse if we do nothing."
This study's projections were enhanced by new observational data from NASA's IceBridge missions, which involves swooping over the Greenland ice sheet to capture detailed measurements of the ice. The airborne NASA mission proved particularly valuable in measuring the conditions of Greenland's exit glaciers -- the rivers of ice that pour into the ocean -- said Aschwanden. With this new information, the research team could simulate how much ice was likely to drain into the sea as glaciers experience an accelerating rise in air temperatures.
"This is really nice work," said Moon, noting that the new incorporation of ice loss around Greenland's edges produced a quality, advanced simulation.
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For all the grim observations from this study, it's crucial to note that things could actually be significantly worse. Yes, worse. That's because these projections may underestimate the powerful influence the warming oceans have on glaciers.
"The oceans have the potential to make this more extreme," said NASA's Willis. "There's still room for [the projections] to get worse."
Arctic waters meet Greenland's colossal exit glaciers, some which are walls of submarine ice around 2,600 feet tall. And recent research, performed by NASA, found these glaciers are extremely sensitive to ocean temperatures. The ocean has the power to accelerate melt, or even stoke the glaciers to start growing again during cooler shifts in ocean circulation.
SEE ALSO:The Green New Deal: Historians weigh in on the immense scale required to pull it offAs airborne scientists, on-the-ground ice-gathering researchers, and satellites scouring from space continue to probe the region, Greenland's future will grow increasingly clear. "The work is ongoing," said Willis.
But the bigger picture is already evident. There are distinct futures ahead for Greenland. Which one will our descendants experience, even beyond this century?
"Two-hundred or 300 years really aren't many human generations," noted Moon. "It will be here in a blink of an eye."
P.S. Asuccinct note to those contending, incredibly, that Greenland is not experiencing drastic melt: One big glacier (Jakobshavn) recently stopped shrinking, but that doesn't mean the entire landmass is miraculously on an epic rebound. "Just because Jakobshavn stopped growing does not mean there’s no global warming and we’re not changing the planet -- we are radically changing the planet," explained NASA oceanographer Josh Willis, who annually flies over Greenland.
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