As glaciers and mountain snow packs recede, their disappearance sometimes reveals archaeological evidence of earlier human settlements, with tools and other implements dropping out of the melting ice. As LiveScience reported back in April, “patches of ice that have been in place for thousands of years in the mountains of the Canadian High Arctic” are disappearing, revealing “a treasure trove of ancient hunting tools” in their wake.
The forensic investigation of these unexpected windows into human history has been dubbed “ice patch archaeology.”
One of the field’s originary archaeologists drew an analogy last week for how these artifacts probably got there:
Maybe you missed a shot and your weapon disappeared into the snowbank. It’s like finding your keys when you drop them in snow. You’re not going to find them until spring. Well, the spring hasn’t come until these things started melting for the first time, in some instances, in many, many thousands of years.
The idea that historical surprises are in store for us, waiting to be revealed—as if by glacial metabolism—in an era of global climate change is a compelling one (and seemingly an inexhaustible plot device for burgeoning writers). In fact, the image that opens this post was taken from John Carpenter’s 1982 film The Thing, in which a spaceship—along with its infectious, shapeshifting passenger—is discovered buried in Antarctic ice that’s at least 100,000 years old. It’s a kind of moving archaeological site, carved from ancient ice and drifting along with the pulse of the glacier.
But we needn’t turn to scifi to find extraordinary examples of “ice patch archaeology.”
Earlier this year, for instance, Atlas Obscura noted a site in Antarctica called “Blood Falls.” It is a “five-story, blood-red waterfall [that] pours very slowly out of the Taylor Glacier in Antarctica’s McMurdo Dry Valleys.”
Roughly two million years ago, the Taylor Glacier sealed beneath it a small body of water which contained an ancient community of microbes. Trapped below a thick layer of ice, they have remained there ever since, isolated inside a natural time capsule. Evolving independently of the rest of the living world, these microbes exist in a world with no light or free oxygen and little heat, and are essentially the definition of “primordial ooze.” The trapped lake has very high salinity and is rich in iron, which gives the waterfall its red color. A fissure in the glacier allows the subglacial lake to flow out, forming the falls without contaminating the ecosystem within.
The scientific value of these previously inaccessible reservoirs of planetary history should only become more obvious in the years to come.
Climate change, together with melting glaciers, becomes an inadvertent archaeology of the human—and profoundly inhuman—past.
But, of course, we’ve seen other stories like this, in which caches of human history unexpectedly reappear as the climate heats up. Last year, for instance, we looked at melting glaciers as chemical archives: “As the world’s glaciers melt, they’ve begun to release an archive of banned industrial substances back into the environment, chemicals that have been locked, frozen, inside the glacial ice for up to thirty years.”
Thirty years is nothing compared to the hundreds—often thousands—of years involved in ice patch archaeology, but the untimely release of dangerous chemicals we once thought long-forgotten is chilling proof that very few things are ever gone for good.