  In this investigation we study the effects of climate change on predator-prey
population dynamics. The interaction of predator and prey is described by the
Variable Territory (VT) model with Allee effects in an Ordinary Differential
Equation (ODE) framework. Climate influence is modeled in this ODE framework as
an exogenous driver which affects the prey growth rate. Mathematically, this
exogenous driver is a function of time, the climate function, that describes
how favorable is the climate, on a scale from $-1$ to $+1$. Climate change has
a number of effects; in this work, we focus on changes in climate variability,
in particular, a decrease in the switching rate between good years and bad.
With regard to the predator-prey populations, we focus on the conditions that
lead to extinction. We developed a high performance software tool to allow the
systematic exploration of a wide range of climate scenarios at a high level of
detail. Our results show that the predator-prey system is sensitive to the
rapid drop in growth rate that accompanies a switch from good growth years to
bad growth years. The amplitude of this negative variation as well as its
duration are key factors, but more importantly, it is the moment when this
negative change occurs during the predator-prey cycle that is critical for the
survival of the species.
