AtChem (version 1), an open-source box model for the Master Chemical Mechanism

Roberto Sommariva, Sam Cox, Chris Martin, Kasia Borońska, Jenny Young, Peter Jimack, Michael J. Pilling, Vasileios Matthaios, Bethany Nelson, Mike Newland, Panagi Marios Panagi, William J. Bloss, Paul S. Monks, Andrew Robert Rickard

Research output: Contribution to journalArticlepeer-review


AtChem is an open-source zero-dimensional
box model for atmospheric chemistry. Any general set
of chemical reactions can be used with AtChem, but the
model was designed specifically for use with the Master
Chemical Mechanism (MCM,,
last access: 16 January 2020). AtChem was initially developed
within the EUROCHAMP project as a web application
last access: 16 January 2020) for modelling environmental
chamber experiments; it was recently upgraded and further
developed into a stand-alone offline version (AtChem2),
which allows the user to run complex and long simulations,
such as those needed for modelling of intensive field campaigns,
as well as to perform batch model runs for sensitivity
studies. AtChem is installed, set up and configured using
semi-automated scripts and simple text configuration files,
making it easy to use even for inexperienced users. A key
feature of AtChem is that it can easily be constrained to observational
data which may have different timescales, thus retaining
all the information contained in the observations. Implementation
of a continuous integration workflow, coupled
with a comprehensive suite of tests and version control software,
makes the AtChem code base robust, reliable and traceable.
The AtChem2 code and documentation are available at (last access: 16 January 2020)
under the open-source MIT License.
Original languageEnglish
Pages (from-to)169-183
Number of pages15
JournalGeoscientific Model Development
Publication statusPublished - 27 Jan 2020

Bibliographical note

© Author(s) 2020.

Part of the "Simulation chambers as tools in atmospheric research" special issue (AMT/ACP/GMD inter-journal SI)


  • Atmospheric Chemistry
  • Simulation chambers
  • Box modelling
  • field experiments

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