Modeling sea level changes and geodetic variations by glacial isostasy: the improved SELEN code

TL;DR

This paper introduces SELEN, an open-source Fortran 90 program that models sea level changes and geodetic variations due to glacial isostasy, with significant improvements in efficiency and usability for scientific and educational purposes.

Contribution

The paper presents an improved version of the SELEN code, enhancing computational efficiency, portability, and versatility for modeling sea level and geodetic variations caused by glacial isostasy.

Findings

Enhanced computational performance in SELEN 2.9

Versatile application to global and regional geodetic problems

Useful educational tool for glacial isostatic adjustment modeling

Abstract

We describe the basic features of SELEN, an open source Fortran 90 program for the numerical solution of the so-called "Sea Level Equation" for a spherical, layered, non-rotating Earth with Maxwell viscoelastic rheology. The Sea Level Equation was introduced in the 70s to model the sea level variations in response to the melting of late-Pleistocene ice-sheets, but it can be also employed for predictions of geodetic quantities such as vertical and horizontal surface displacements and gravity variations on a global and a regional scale. SELEN (acronym of SEa Level EquatioN solver) is particularly oriented to scientists at their first approach to the glacial isostatic adjustment problem and, according to our experience, it can be successfully used in teaching. The current release (2.9) considerably improves the previous versions of the code in terms of computational efficiency, portability and versatility. In this paper we describe the essentials of the theory behind the Sea Level Equation, the purposes of SELEN and its implementation, and we provide practical guidelines for the use of the program. Various examples showing how SELEN can be configured to solve geodynamical problems involving past and present sea level changes and current geodetic variations are also presented and discussed.