Properties of coastal Antarctic aerosol from combined FTIR spectrometer and sun photometer measurements

Remotely sensing the physical and chemical properties of summertime aerosol at the Antarctic coastal station Neumayer has been accomplished for the first time by a combined analysis of atmospheric thermal emission spectra, measured by an FTIR spectrometer, and atmospheric visible‐near infrared extinction spectra, measured by a sun photometer. From the synergy of both spectral ranges, we find that the aerosol is composed of 1.1–1.6 mg m−2 of sulfates, with the water component in the solid phase, having a bimodal size distribution with radii peaking at 0.04 and 0.64 μm. We also provide the first estimate of the direct thermal radiative forcing of this aerosol: +1.68 W m−2 at the surface, and +0.006 W m−2 at the top of the atmosphere.