Novel optical absorption approach for black carbon (BC) measurement in snow
□ We developed a method to quantify tracq. levels of BC in snow. The approach should have general applicability to many aqueous systems. □ The method requires only a few mL of melted snow, unlike other approaches which demand many liters of snow. The approach is ideally suited for limited volume ice-core thin sections and, importantly, can be readily interfaced to continuous ice and snow melting devices for real-time analysis. □ Only minimal sample preparation is required, thus the potential for contamination and loss biases are reduced. The analysis can be performed on-site, eliminating transport/storage impacts. □ The optical approach exhibits high signal-to-noise metrics; superior to alternative methods. Information rich spectra are acquired over the wavelength range of 400 to 700 nm. □ The correction for light absorption from soluble species is small (<6%), while the inorganic (soil-dust) correction can be much larger (20-60%). □ Measured BC concentrations are consistent with those reported for remote arctic snow.
