Excessive Carbon Bonding Is Breaking Glaciers

Ice caps and glaciers cover nearly seven percent of Earth.  They are responsible for reflecting nearly 80-90 percent of the Sun's rays that enter our atmosphere and maintain Earth's temperature. They also capture a great amount of carbon dioxide (CO2)_.  But it appears that excessive CO2 is causing a crack.

The researchers from the Massachusetts Institute for Technology have shown that the material strength and fracture toughness of ice has decreased significantly due to the escalating concentrations of CO2 molecules. This increased level of CO2 is causing the ice caps and glaciers to crack and split into pieces.

A good example of the disastrous effect of increasing CO2 was clearly evident in the recent glacier split in the Pine Island Galcier in Antarctica.

The new study highlights the fact that CO2 molecules have a direct impact on the ice that covers our planet.

"If ice caps and glaciers were to continue to crack and break into pieces, their surface area that is exposed to air would be significantly increased, which could lead to accelerated melting and much reduced coverage area on the Earth. The consequences of these changes remain to be explored by the experts, but they might contribute to changes of the global climate," said lead author of the study Professor Markus Buehler. He conducted this study along with his student and co author of the paper Zhao Qin.

For the study they both used a series of atomistic-level computer simulations to analyze the dynamics of molecules to investigate the role of CO2 molecules in ice fracturing. They found that CO2 exposure triggers ice to break more easily.

Apparently, it is not the material defects induced by carbon that decreases the ice strength. But it is the strength of the hydrogen bonds that is decreased under increasing concentrations of CO2. The reason behind this is the added carbon dioxide competes with the water molecules connected in the ice crystal.

According the research, the CO2 molecules first adhere to the crack boundary of ice by forming a bond with the hydrogen atoms and then migrate through the ice in a flipping motion along the crack boundary towards the crack tip. The CO2 molecules then begin to mount up at the crack tip and constantly attack the water molecules by trying to bond to them.  And this leaves broken bonds behind and increases the brittleness of the ice on a macroscopic scale.

The details are being published on October 11, in IOP Publishing's Journal of Physics: Applied Physics.