Melting isn’t an possibility as a result of carbon dioxide simply dissolves into water. Traditionally, scientists have used mechanical extraction strategies, grinding up samples of particular person layers of ice to free the air. But grinding wouldn’t be efficient for the Beyond EPICA ice within the college’s storage freezer, which is saved at 50 °C beneath zero. The oldest ice on the very backside of the core might be so compressed, and the person annual layers so skinny, that bubbles received’t be seen—they’ll have been pressed into the lattice of ice crystals, forming a brand new section referred to as clathrate.
“At the very bottom, we expect 20,000 years of climate history compressed in only one meter of ice,” says Hubertus Fischer, head of the previous local weather and ice core science group at Bern. That’s a hundredth the thickness of any current ice core file.
The new methodology Krauss and Fischer are growing is known as deepSLice. (A pizza menu is taped to the aspect of the system proper below the laser warning labels, a present from a pizzeria in Australia with the identical title.) DeepSLice has two elements. The Laser-Induced Sublimation Extraction Device, or LISE, fills half a room within the workforce’s lab area. LISE goals a near-infrared laser constantly at a 10-centimeter slice of ice core in order that it turns immediately from stable to gasoline below extraordinarily low stress and temperature. The sublimated gasoline then freezes into six steel dip tubes cooled to fifteen Okay (-258 °C), every containing the air from one centimeter of ice core. Finally the samples are loaded right into a custom-made absorption spectrometer based mostly on quantum cascade laser expertise, which shoots photons by means of the gasoline pattern to measure concentrations of carbon dioxide, methane, and nitrous oxide concurrently. Another massive benefit of this method is that it takes quite a bit much less ice (and work) than the outdated methodology of research, through which scientists measured methane by melting ice (it doesn’t dissolve into water) and measured carbon dioxide by grinding ice.
DeepSLice gives “a unique capability that nobody else has,” says Christo Buizert, an ice core scientist at Oregon State University and the ice evaluation lead for COLDEX (the Center for Oldest Ice Exploration)—the US equal of Beyond EPICA, which is presently in a “friendly race” with the Europeans to drill a steady core right down to 1.5-million-year-old ice.