Photobiology and Optical Properties of Planktonic and Sea Ice Microalgae in theHigh Arctic

摘要

Time series studies of the spectral irradiance fields beneath multiyear pack icewere conducted in the Eastern Arctic Basin at 82-83 deg N as part of the Coordinated Eastern Arctic Research Experiment (CEAREX). Particulate matter was collected from the multiyear pack ice as well as first year ice in a refrozen lead. The vertical distribution within the ice and the spectral absorbtion properties of the particulates were determined in order to estimate their contribution to the optical properties of the sea ice. Among the particulates contained in sea ice detritus was common throughout all portions of the pack ice and was the major light absorbing particulate matter in the ice at the time of the observation. Algal cells and mineral-like particulates also were present, yet they contributed to the light-absorbing properties to a lesser extent than the detritus. During early spring, particulate matter contributed little to the bulk attenuation coefficients of the multiyear ice, however, it was estimated to have a more substantial contribution to the attenuation coefficients of first year ice in a refrozen lead. Results of a single stream multilayer radiative transfer model that simulates concentrations of biogenic particulate matter observed in Arctic sea ice indicates that particulate matter within sea ice plays a substantial role in radiative energy transfer and has the potential to seasonally alter spectral irradiance regimes within the ice covered Arctic ocean.