Towards an Investigation of the Effects of Dynamic Topography on
Vertical Land Motions Along the North American Atlantic Coast
Abstract
Dynamic topography, defined as the deflection of the Earth’s surface due
to the convecting mantle, causes changes in vertical land motions (VLM).
We aim to estimate the effect of dynamic topography on VLM along the
North American Atlantic Coast, which is a region where land subsidence
influences relative sea-level rise and other coastal hazards. The
contribution of dynamic topography to VLM continues to be debated since
previous studies show a range in the rate change of dynamic topography
for this region, which are in part due to uncertainties in Earth’s
rheology. In this investigation, we model global mantle convection to
better assess the role of dynamic topography on VLM along the North
American Atlantic Coast. We are implementing a time-dependent approach
using the finite element code ASPECT (v2.2.0). We constrain our initial
temperature conditions using the tomography models SAVANI, GYPSUM,
S40RTS, and TX2008 and then explore both linear and non-linear
rheological models. The two rheological models allow us to assess
differences in the rate change of dynamic topography globally with a
nonlinear rheology compared to a linear rheology. We expect this work
will allow us to better understand the contribution of dynamic
topography to VLM along the North American Atlantic Coast.