Quantifying the effects of background concentrations of crude oil pollution on sea ice albedo

Abstract. Sea ice albedo plays an important role in modulating the climate of Earth and is affected by low background concentrations oil droplets within matrix that absorb solar radiation. In this study, response three different types bare sea (melting, first-year, multi-year ice) are calculated at increasing mass ratios (0–1000 ng g?1) crude using a coupled atmosphere–sea radiative-transfer model (TUV-snow; Tropospheric Ultraviolet–Visible) over optical wavelengths 400–700 nm. The quasi-infinite-thickness exhibit responses to pollution, with 1000 g?1 ratio causing decrease 70.9 % ice, 47.2 first-year 22.1 melting relative unpolluted wavelength 400 thickness also factor, realistic-thickness ices exhibiting similar results, albeit weaker for 75.3 %, 66.3 35.9 %. type significantly affects albedo, relatively opaque heavy (Romashkino oil) larger than transparent light (Petrobaltic oil). size polluting minor response, weathered submicrometre (0.05–0.5 µm radius) Romashkino being most absorbing across considered. Therefore, work presented here demonstrates small submicrometre- micrometre-sized have significant effect on ice. All sensitive pollution; however, particularly very pollution.