<title>Extinction coefficients and phase functions of particle size distributions measured inside cloud layers</title>

Abstract

The vertical structure of the atmospheric aerosols was investigated during cable car ascents along a steep mountain slope in the German Alps. Aerosol size distributions were measured by operating two particle spectrometer probes with diameter ranges of 0. 15 -3 im and 1 -95 rim. Aerosol and hydrometeorits were sampled under the meteorological conditions of clear atmosphere, haze and thick clouds. For each atmospheric layer the phase function P(O) and the extinction coefficient next were calculated for the visual (X = 0.55 rim), the near JR with Nd:YAG laser radiation (X = 1 .064 rim) and iodine laser radiation (= 1.3 15 Mm) and the middle JR with CO2 laser radiation (? = 10.59 rim) using the computer code AGAUS of the EOSAEL program library of the US Army Research Lab. Jn the visual and the near JR the aerosol extinction coefficient is not sensitive to variations of the complex refractive index. However for the CO2 laser radiation, the uncertainty in the values of optical constants causes large deviations in calculated aerosol extinction coefficients.

<title>IR imaging of a point target through inhomogeneous media along a slant path of 2.3 km</title>

“…A more detailed analysis ofthe FGAN-FfO aerosol measurements can be found in [5]. A block diagram of the transmissometer is shown in Figure 5.1.…”