Radiative Transfer Modeling of Atmospheric Limb Observations in the UV/vis/nearIR spectral range
The interpretation of atmospheric limb measurements in require detailed radiative transfer modeling (RTM) for each individual observation. Our research group performs such skylight limb measurements in the UV/vis/near-IR spectral range with optical spectrometer deployed on various platforms, such as aircrafts (the DLR Falcon and HALO, the Russian Geophysica, the NASA Global Hawk) and high flying balloons (LPMA/DOAS, MIPAS, SALOMON, …). Targeted gases of our measurements are O3, NO2, HONO, BrO, IO, OClO, CH2O, C2H2O2, ….., and all three phases of water. Such optical measurements are best suited to provide novel insights into some atmospheric processes, which are not easily accessible by other techniques. Specific research objectives include the budget and photochemistry of halogens in the troposphere and lower to middle stratosphere, the photochemistry of ozone depletion events during arctic spring, the photochemistry and microphysics of thunderstorm clouds, air pollution per!
se, the amount and occurrence of cirrus clouds in particular in areas (tropics), where they exert considerable influence on the climate, and the microphysics of mixed phased clouds, beside other research objectives.
RTM is needed and supports the interpretation of limb measurements by providing the relevant forward information for inverse modeling of each individual observation. Since the quality of the forward modeling co-determines the quality of our remote sensing technique, the best choice of RTM requires a realistic representation of all relevant radiative processes in the atmosphere. These processes include scattering (Rayleigh, Mie, and Raman scattering), gaseous and particle absorption, the ground albedo et cetera. RT models at hand are either so called discrete ordinate or Monte Carlo codes.
The offered PhD thesis will address atmospheric RTM in general and particular emphasis will be put on a more realistic description of particle scattering than presently available, either using the full Mie theory, or variants if it (i.e. the T-matrix technique, or Discrete Dipole Approximation (DDA), …).
In Germany, a PhD work typically takes about 3 years including continuing education, and teaching. Knowledge of the German is not required, since teaching is in English in demand. Support is given via a research grant on the basis of a TVL-13 payment. The applicant needs to have passed a full physics study (master) with a rating better than ‘good’ according to the ECTS rating. For details of the PhD physics program in Heidelberg, see http://www.physik.uni-heidelberg.de/index.php?lang=en and for the PhD rules http://www.physik.uni-heidelberg.de/studium/Promotion/index_en.html
Contact:
Prof. K. Klaus Pfeilsticker, Institute for the Physics of the Environment (Umweltphysik), University of Heidelberg, Germany, phone: 0049-6221-546401
email: Klaus.Pfeilsticker@iup.uni-heidelberg.de