Global warming reached central Greenland (over a decade ago)


Even with all of our fancy technology, fieldwork in places like central Greenland remains difficult and dangerous. The conditions are unforgiving, and the ground is treacherous. That’s why, despite the global importance of studying the ice sheet, expeditions into the heart of that island aren’t particularly common. A recently published study shows the results of an effort to update our ice core data. Previous cores from the 1990s didn’t show clear evidence of warming, but the new data, extending to 2011, is very different:

“The time series we recovered from ice cores now continuously covers more than 1,000 years, from year 1000 to 2011. This data shows that the warming in 2001 to 2011 clearly differs from natural variations during the past 1,000 years. Although grimly expected in the light of global warming, we were surprised by how evident this difference really was,” says AWI glaciologist Dr Maria Hörhold, lead author of the study. Together with colleagues from AWI and the University of Copenhagen’s Niels Bohr Institute, she analysed the isotope composition in shallow ice cores gathered in central-north Greenland during dedicated AWI expeditions.

[…]

The AWI researchers have now extended the previous datasets up to winter 2011/2012 by a dedicated redrilling effort, recovering time series unprecedented length and quality. The temperatures were reconstructed by using consistently one single method for the entire record in the lab: measuring concentrations of stable oxygen isotopes within the ice, which vary with the temperatures prevailing at times of ice formation. Previous studies had to draw on a range of different climate archives and combine results to reconstruct temperature, introducing much larger uncertainties in the assessment of natural variability.

In addition to the temperature, the team reconstructed the melt production of the ice sheet. Melting has increased substantially in Greenland since the 2000s and now significantly contributes to global sea-level rise. “We were amazed to see how closely temperatures inland are connected to Greenland-wide meltwater drainage – which, after all, occurs in low-elevation areas along the rim of the ice sheet near the coast,” says Maria Hörhold.

As Dr. Hörhold stated, this result was, to some degree, expected. The planet has warmed so much, and has been reacting to that warming so much, that there was very little chance that it wouldn’t be detectable by 2011. It’s nice that scientific understanding of the climate is good enough that expectations more or less match reality, but obviously it’d be nice if things were moving a bit more slowly. These data don’t change what needs to be done, and they don’t really change the urgency. It’s certainly frightening to hear that one of the coldest places of the earth is warming so dramatically, but I think it’s good to remember that our need for swift action is not driven by models or ice cores, but by the effects that the tiny amount of warming we’ve seen so far is already having on humanity.

I recently had a bit of a discussion with a longtime reader about the eugenicist history of the environmental movement, and it’s a good reminder of the importance of centering humanity as a whole in how we respond to environmental crises and injustices. A lot of environmentalism over the last century has followed the notion that humanity is somehow separate from the rest of this planet’s biosphere, and that advances in technology are some level of “unnatural”. This has been used, at times, as a justification for the under-development of the so-called Global South. Efforts to stop deforestation, for example, put the focus on the people doing it, rather than the systemic factors that made put them in that position in the first place.

The first example of a better approach that I personally saw was at the Kakamega Rainforest in Kenya. During the Moi regime, someone lower down in the government came up with the idea of putting a tea plantation around the rainforest, and employing the locals to work there. The basic idea was to provide them with a means of survival other than hunting in the forest. I’m sure it’s far from a perfect solution, but it was the first time I’d seen an environmental project that focused on the factors that caused people to do “bad” things.

That arrangement, however, still relies on the notion that keeping people out of “nature” is the best way to safeguard that nature from “human nature” as defined by a colonialist, capitalist society. The modern movement for environmental justice is trying to be something different, centering humanity’s right to personal autonomy and self-governance as inseparable from the environmental issues facing us. It aims its ire not at the people who are actually doing the clear-cutting, but on the global capitalist system its endless drive for ever-increasing profit, humanity and nature be damned. We’re trying to build something new, informed by science like this Greenland study, as well as science surrounding humans and our history. That’s why it’s good to know about this research, even though I honestly think that it should not affect your day to day life much if at all. This stuff informs me, but it’s not what drives me, if that makes sense.

And on that note, this study gave us another interesting finding – it turns out Greenland sort of has its own microclimate, separate from the rest of the Arctic:

Another exciting finding from the study: the climate of the Greenland Ice Sheet is largely decoupled from the rest of the Arctic. This could be shown in comparison with the Arctic-wide temperature reconstruction ‘Arctic 2k’. Although ‘Arctic 2k’ is an accurate representation of the circumpolar region, it does not reflect the conditions in central Greenland. “Our reconstruction now offers a robust representation of temperature evolution in central Greenland, which has proven to have a dynamic of its own,” says Prof. Thomas Laepple, AWI climate researcher and co-author of the study. “Actually, we had expected the time series to strongly covary with the warming of the Arctic region,” Laepple reports. But the authors have an explanation for these differences: the ice sheet is several kilometres thick; because of its height, Greenland is more affected by atmospheric circulation patterns than other parts of the Arctic. Temperature time series on the Arctic with regional resolution are needed, says Laepple, in order to reliably describe climate change in the Arctic.

I periodically run into people on Twitter and such places who insist that the world is too complex for us to ever understand or influence, and I honestly find that to be a bit of a depressing outlook. The last person that told me that had also openly said that he doesn’t need to know what climate scientists have to say about all this. That seems like a very self-limiting approach to life. It’s like he’s in Plato’s cave, and someone went out, saw the rest of the world, came back and told him about it, and he just dismissed them without even turning his head.

The world is complex – wonderfully so. It sometimes feels as though most of our problems come from people who desperately want that to not be the case. Personally, I love finding out that the Greenland ice sheet is such a massive chunk of ice that it stands out from the rest of the Arctic, a place that’s rather well known for having a lot of ice. Maybe I’ve just achieved some level of enlightened detachment, but stories like this give me just a glimpse of what it might be like to watch this incredible, planet-spanning change take place from the point of view of a scientist who is somehow not emotionally invested in the outcome.

It’s just a glimpse, because I am emotionally invested, but it’s still there. Nothing like this has ever happened in human history, and it’s teaching us all sorts of things about how the many interlocking systems of this planet function. We’re seeing how it affects migratory species that don’t rely on weather for migration cues. We’re seeing how it affects animals’ body sizes, and plants’ toxicity. We’re seeing how changes in the Arctic affect life thousands of miles away. We’re seeing what happens when a species creates chemical compounds that never existed before, and spreads them across the planet.

It often sucks to be a part of it, but it is absolutely fascinating to watch. I think it helps that I feel like I’m more or less doing what I’m able to at this point in time. I’d like to do more, but I’ve come to accept that I have limits on what I’m can to do, and when can do it. All of that buys me enough space to be able to appreciate how cool it is that people were able to go drill a few holes in the ice in north-central Greenland, and get so much intelligible information about the world’s past and present from that. For all the man-made horrors beyond our comprehension, it’s still a strange and wonderful world.

 

Leave a Reply

Your email address will not be published. Required fields are marked *