Investigation of the inherent and apparent optical properties of atmospheric aerosol and the untangling of the absorption spectrum using the photoacoustic method [antikvár]

1. Introduction One of the most significant scientific goals of our time is the reliable I and precise determination of the anthropogenic climate modifying impacts. [ Despite the fact that the role of atmospheric aerosol is comparable to that of ^ greenhouse gases regarding the shifts in the radiative balance of the Earth-atmosphere system, considering their inherent (freshly after emission) and the apparent (in the atmospheric equilibrium state) optical properties there is only limited and mostly uncertain data available. Our knowledge on absorption properties is incomplete and unprecise regarding both carbonaceous aerosol being dominant in number-concentration while having strong specific absorption and mineral dust being dominant in mass-concentration while having low specific absorption. This has major impact on the uncertainties regarding the estimations on the global climate forcing of aerosol. Atmospheric aerosol are in the focus of scientific interest not only because of their cHmatic impact but also their effect on air quality. Based on our current knowledge, however, atmospheric soot aerosol are negligible in mass-concentration, they are the largest contributors to the toxicity of particulate matter. The investigation of human health impacts and the apportionment of emitting sources is one of the biggest scientific challenges of our time. Latest researches have shown significant relationship between the chemical composition and the optical absorption spectra of aerosol, which can be measured in real time. This opens novel possibilities in the field of the realtime source apportionment of these aerosol. The fact that, despite of its significance, we do not have sufficient information on the absorption response of atmospheric aerosol can be traced back to several reasons, like the lack of instrumentation, which is capable of providing reliable data with sufficient sensitivity, the difficulties of the