We measured Raman spectra (RS) of ambient aerosols semi-continuously, to determine the compositions of individual aerosol particles at 15-20 minute time-resolution. The automated aerosol-Raman spectrometer (ARS) we use is Battelle’s (Columbus, OH) REBS. Many RS exhibit a broad luminescence, which can vary from one replicate to another because of photobleaching, thermal changes in crystal structure, or other phenomena. Materials consistent with the measured RS include DG carbon, organic carbon, and minerals such as calcite and quartz. We illustrate differences in the compositions consistent with the RS observed at a semi-urban site in Maryland and a rural site in New Mexico.
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