GLM : The General Lake Model

The General Lake Model (GLM) is a water balance and one-dimensional vertical stratification hydrodynamic model. It accounts for the effect of inflows/outflows, mixing and surface heating and cooling, including the effect of ice cover. It is suited to longer-term investigations ranging from seasons to decades, and for coupling with biogeochemical models to explore the role that stratification and vertical mixing has on biogeochemical and ecological dynamics of lakes, reservoirs, ponds and wetlands.

Release status

Important

GLM 4.0.0 is in a pre-release state.

This repository holds the actively developed GLM source line. It has not yet had a tagged 4.0 release: input configuration, module options and output variables may still change ahead of that release. Users who need a stable, citable version should work from the most recent published GLM-AED release and should expect to revisit their configuration when 4.0.0 is finalised.

Version lineage

Line	Repository	Status
GLM 4.x	this repository	Active development — pre-release
GLM 3.x	GLM3	Archived, no longer developed

The 3.x line is preserved in the GLM3 repository, where its tagged releases (through GLM_v3.3.0, source to 3.3.5) and full commit history remain available for reference and for reproducing older simulations. New development, including everything below, happens here and is not backported to 3.x.

GLM 4.x extends the 3.x line with a restructured AED coupling interface (via libaed-api), an integrated particle tracking module, a reworked surface heat exchange module, and in-core bubbler/destratification and oxygenation modules — the last two of which were previously distributed as optional source patches against GLM 3.

Accessing the model

This GLM repository is released coupled with the AED water quality model, via the GLM-AED release. Refer to the glm-aed repository for pre-compiled model executable files, example simulations, and information for how to get started with the model. Note that current glm-aed releases build against this 4.x source line and are not compatible with GLM3.

Reference

Refer to the following paper for a scientific description of the model:

Hipsey, M.R., Bruce, L.C., Boon, C., Busch, B., Carey, C.C., Hamilton, D.P., Hanson, P.C., Read, J.S., de Sousa, E., Weber, M. and Winslow, L.A., 2019. A General Lake Model (GLM 3.0) for linking with high-frequency sensor data from the Global Lake Ecological Observatory Network (GLEON). Geoscientific Model Development, 12(1), pp.473-523. https://doi.org/10.5194/gmd-12-473-2019

This paper documents the GLM 3.0 formulation, which remains the core of the 4.x line.