  Molecular signals are abundant in engineering and biological contexts, and
undergo stochastic propagation in fluid dynamic channels. The received signal
is sensitive to a variety of input and channel parameter variations. Currently
we do not understand how uncertainty or noise in a variety of parameters affect
the received signal concentration, and nor do we have an analytical framework
to tackle this challenge. In this paper, we utilize Polynomial Chaos Expansion
(PCE) to show to uncertainty in parameters propagates to uncertainty in the
received signal. In demonstrating its applicability, we consider a Turbulent
Diffusion Molecular Communication (TDMC) channel and highlight which parameters
affect the received signals. This can pave the way for future information
theoretic insights, as well as guide experimental design.
