Last month saw the average concentration of atmospheric carbon dioxide (CO2) climb to almost 418 parts-per-million, a level not seen on Earth for millions of years. In order to get a sense of what our future may hold, scientists have been looking to the deep past.
Last month saw the average concentration of atmospheric carbon dioxide (CO2) climb to almost 418 parts-per-million, a level not seen on Earth for millions of years. In order to get a sense of what our future may hold, scientists have been looking to the deep past. Now, new research from the University of Massachusetts Amherst, which combines climate, ice sheet and vegetation model simulations with a suite of different climatic and geologic scenarios, opens the clearest window yet into the deep history of the Antarctic ice sheet and what our planetary future might hold.
The Antarctic ice sheet has attracted the particular interest of the scientific community because it is “a lynchpin in the earth’s climate system, affecting everything from oceanic circulation to climate,” says Anna Ruth Halberstadt, a Ph.D candidate in geosciences and the paper’s lead author, which appeared recently in the journal Earth and Planetary Science Letters. Additionally, the ice sheet contains enough frozen water to raise current sea levels by 57 meters.
Yet, it has been difficult to accurately reconstruct the mid-Miocene Antarctic climate. Researchers can run models, but without geologic data to check the models against, it’s difficult to choose which simulation is correct. Conversely, researchers can extrapolate from geologic data, but such data points offer only local snapshots, not a wider climatic context. “We need both models and geologic data to know anything at all,” says Halberstadt. There’s one final complicating factor: geology. Antarctica is bisected by the Transantarctic Mountains, and any clear picture of Antarctica’s deep history must be able to account for the slow uplift of the continent’s mountain range. “Without knowing the elevation,” says Halberstadt, “it’s difficult to interpret the geologic record.”
Read More: University of Massachusetts Amherst
Lead author Anna Ruth Halberstadt in Antarctica (Photo Credit: Anna Ruth Halberstadt)
