Predicting the Effect of Carbon Soot Particles on the Melting Rate of Ice: Theoretical and Experimental Investigations

Abstract

Un-burnt carbon particles (soot particles) have been known to be highly absorbing in the solar irradiance wavelength band and thus have a significant impact on regional and global climate patterns. Furthermore, these particles when entrapped in the glacier ice, can affect the melting rate of the glaciers, which in turn can affect the global sea levels. The present work serves to understand and quantify the effect of soot particles on the melting rate of glaciers. A comprehensive mathematical model has been developed to simulate the melting process in glaciers. Interaction of sunlight with the glacier ice essentially being a volumetric phenomenon has been modeled as radiative heat transfer in participating media. Spectral radiant energy from the sun interacts with ice (and the entrapped soot particles) through absorption and scattering mechanisms. The magnitudes of the optical constants of the ice constituents dictate the amount of sunlight absorbed and hence the melting rate. Theoretical calculations show that even trace amounts of soot particles can significantly increase the melting rate under similar ambient conditions, 100 parts-per-million (ppm) concentration of carbon soot particles can increase the melting rate by approximately 4.65%. Furthermore, the soot particle size, and concentration have been identified as the key parameters that govern the melting process. Finally, laboratory scale proof of the concept experiments have been carried out to verify the theoretical hypothesis.