Impacts of coal dust from an active mine on the spectral reflectance of Arctic surface snow in Svalbard, Norway

Abstract

Light‐absorbing particles (LAPs) in snow such as dust and black carbon influence the radiative forcing at the Earth's surface, which has major implications for global climate models. LAPs also significantly influence the melting of glaciers, sea ice, and seasonal snow. Here we present an in situ study of surface snow near an active coal mine in the Norwegian Arctic. We couple measurements of spectral hemispherical directional reflectance factor (HDRF) with measurements of LAPs characterized in two ways, as refractory black carbon using a Single Particle Soot Photometer and the total light absorption of LAPs measured with the Light Absorption Heating Method. The Snow Ice and Aerosol Radiation model was constrained by LAP measurements. Results were compared to observed spectral albedo measurements. Modeled and observed albedos were similar at the cleaner and more remote sites. However, the modeled spectral albedos do not fully account for the low spectral albedo measured next to the mine. LAP measurements also showed a large variation in particle sizes (tenths to tens of microns) related to transport distance of the particles from the mine. Here we find that LAPs from coal dust reduce the spectral HDRF by up to 84% next to the mine and 55% 0.5 km downwind of the mine. The coupling of extreme LAP observations (1 ng g−1 to 4863 ng g−1) with HDRF measurements from 350 to 2500 nm has facilitated the development of spectral band pairs, which could be used in the future to remotely assess LAPs in Arctic snow.

Hyperspectral Measurements, Parameterizations, and Atmospheric Correction of Whitecaps and Foam From Visible to Shortwave Infrared for Ocean Color Remote Sensing

“…For the data collected here, the depth of the trough related to liquid water absorption is related to the derived whitecap factor for the 980 and 1,200 nm features. A baseline subtraction approach (also referred to as continuum removed) has proven to be robust for many environmental remote sensing applications (Clark, 1999;Dierssen et al, 2015;Khan et al, 2017;Garaba and Dierssen, 2018) and is explored here (Figure 10). The water absorption features at ∼750 nm is not a robust indicator when the whitecap factor is low.…”

The spectral and chemical measurement of pollutants on snow near South Pole, Antarctica

“…[] and snow near a coal mine in Svalbard with refractory BC 345 ppb, effective BC 4900 ppb, reported in Khan et al . []).…”

“…For example, Pb was measured at~4-5 times background levels since 1960s [Boutron, 1982;McConnell et al, 2014], and Ba concentration was found to be a factor of 23 greater since 1980 [Korotkikh et al, 2014]. Khan et al [2017]; pollution on snow, [Simões and Zagorodnov, 2001]; and ablation zone in Greenland, [Wientjes and Oerlemans, 2010]). Greater magnitude impurity concentrations on snow and ice can not only be detected with remote sensing but also geochemically differentiated [Gleeson et al, 2010;.…”

Black Carbon and Inorganic Aerosols in Arctic Snowpack

“…To accurately measure the size distributions of BC in snow in this study, we used a single-particle soot photometer (SP2) based on a laser-induced incandescence technique, combined with a nebulizer (Kaspari et al, 2011;Lim et al, 2014;McConnell et al, 2007;Mori et al, 2016;Sinha et al, 2018;Wendl et al, 2014). The nebulizer/SP2 system has been used to measure the size distribution of BC in snow at Alert in Nunavut, Canada, and at Ny-Ålesund, Woodfjorden, and Mine in Spitsbergen, Norway (Khan et al, 2017;Macdonald et al, 2017;Sinha et al, 2018). In particular, Sinha et al (2018) investigated the seasonal progression of deposition of BC by snowfall at Ny-Ålesund.…”