| dc.description.abstract | In the first part of this dissertation, radiative interactions with single irregular particles
are simulated. We first introduce the basic method and techniques of Finite-
Difference Time-Domain method(FDTD), which is a powerful method to numerically
solve Maxwell's equations with high accuracy. To improve the efficiency of FDTD,
we also develop a parallel FDTD code. Since FDTD can simulate light scattering
by arbitrary shape and compositions, we study several radiative interaction cases for
single particles in an external plane parallel light source: the surface roughness effects
on the scattering, electric and magnetic energy density distribution in irregular particles,
and backscattered Mueller images. We also develop an innovative and accurate
method to simulate the infinitesimal electric dipole radiation from inside a particle
with arbitrary shape and composition. Our research and results are very important
to study light scattering by irregular particles, Raman scattering and fluorescence.
In the second part of the dissertation, we study radiative interactions in an
atmosphere-ocean system. By using the so called Matrix operator method, not only
the radiance of the radiation field, but also the polarization of the radiation field
are obtained. Given the single layer information for the atmosphere, time dependent
ocean surface shapes, and the ocean with no interface, the Matrix operator method couples these three layers and provides both the radiance and polarization reaching
a certain detector in the time domain, which are essential for atmospheric science
and oceanography. Several simple cases are studied by this method to demonstrate
its accuracy and robustness. We also show the most difficulties in this method and
discuss what one need to do in future research works. | en |
