SimSphere: A Biosphere/Atmosphere Simulation

Figure: the basic structure of SimSphere modelSimSphere is a soil/vegetation/atmosphere/transfer (SVAT) model that simulates the interactions among soil, plant, and atmospheric systems and the transfer of energy, momentum, and water through the systems. It was created by Penn State meteorology professor Toby N. Carlson and a team of developers and instructional designers, with contributions at a later stage by Dr George P. Petropoulos, Senior Lecturer in Remote Sensing & GIS at Aberystwyth University.

The SimSphere package, consists of an interactive model written in Java, a 13-chapter student workbook, and a Users' guide. The student workbook introduces simple concepts and the software reinforces them. Users have the option of running the model as an applet from a web browser or downloading the model to a Microsoft Windows®-based personal computer and running it as a stand-alone application.

The package is designed for undergraduates, graduate students, and professionals in disciplines such as geography, meteorology, landscape architecture, and civil engineering. SimSphere apart from its use as a stand-alone application it can be used synergistically with optical and thermal infrared Earth Observation data from either aircrafts or satellites to derive regional estimates of soil surface moisture content and energy fluxes (latent and sensible heat fluxes), both instantaneous and daytime averages.

This software product is released under the terms of the GNU General Public Licence (

To cite the model when use it in your work, please use the following citations:

  • Carlson, T.N.; Boland, F.E. Analysis of urban-rural canopy using a surface heat flux/temperature model. Journal of Applied Meteorology,  1978, 17, pp: 998-1013
  • Petropoulos, G., Carlson, T.N. and M. J., Wooster (2009): An Overview of the Use of the SimSphere Soil Vegetation Atmosphere Transfer (SVAT) Model for the Study of Land-Atmosphere Interactions. Sensors, 2009, 9(6), 4286-4308, DOI

A User's SimSphere group has been set up on LinkedIn as  "The SimSphere Land Biosphere Model Users Group"; please sign up if you would like to join the group or email George Petropoulos ( Cette adresse e-mail est protégée contre les robots spammeurs. Vous devez activer le JavaScript pour la visualiser. ) requesting a personal invite to join.

A special issue on SimSphere model exploitation is currently open for contributions to the open access journal Geoscientific Model Developments. This special issue hosts contributions concerned with descriptions of further upgrades of SimSphere or its exploitation in any way. It comprises articles on model developments or applications involving the model; this includes – but is not limited to – studies exploring hypothetical scenario examination, model validation, sensitivity analysis and synergies of it with EO data. More information about the special issue and the submission process can be found HERE

SimSphere Workbook: Table of Contents


For more information please contact:

Faculty of Natural Sciences & Life and Earth Sciences,
University of Bouira
10000, Bouira
Email:  Cette adresse e-mail est protégée contre les robots spammeurs. Vous devez activer le JavaScript pour la visualiser.
Mobile: +213 540 466 156


Simsphere is currently useed within DGES in both undergraduate and postgraduate teaching in the modules;

  • The Atmosphere and the Water Cycle (EA12210)

  • Skills in Remote Sensing (EAM3620)


@ 2013, Aberystwyth University (AU), Wales, United Kingdom

Initial model development:

Pennsylvania State University (PSU) Department of Meteorology, USA.

Major Revisions, Maintenance, Global Distribution:

Aberystwyth University, Department of Geography & Earth Sciences, UK




Aberystwyth University (UK):

George P. Petropoulos – Faculty

Pennsylvania State University (USA): 

Toby Carlson – Faculty

Karen Peters – Instructional design

Tim Summers – Lead programmer

David Ripley – Model programmer

Brian Shook - Database backend programmer

Jason Meyer – Programmer

Sudhanshu Thanedar – Programmer

INFOCOSMOS Ltd (Greece): 

Yiannis Konstas – Programmer

Running the SimSphere Model

You can download a Java application(0.96mb)

Minimum System Requirements: Windows 95/98/NT/2000 with Java Runtime Environment 2.4 or later.


User Guides