Articles | Volume 19, issue 19
https://doi.org/10.5194/gmd-19-9751-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-19-9751-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
EnviFlux (v1.0): a simplified surface flux inversion tool based on four-dimensional variational data assimilation (4D-Var)
Ross N. Bannister
CORRESPONDING AUTHOR
Dept. of Meteorology, Univ. of Reading, Whiteknights Road, Earley Gate, Reading, RG6 6ET, UK
National Centre for Earth Observation, Space Park Leicester, Corporation Road, Leicester, LE4 5SP, UK
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Short summary
EnviFlux is a low-cost data assimilation tool to estimate trace gas fluxes at the Earth's surface. Data assimilation ideas are often first studied with "toy models", but none exists for flux estimation, hence the purpose of EnviFlux.
EnviFlux is described, and then used to show how model error and bias can influence the inferred surface flux features. This is done in two scenarios, one with no prior knowledge of a source/sink pair, and another with prior knowledge in a more realistic situation.
EnviFlux is a low-cost data assimilation tool to estimate trace gas fluxes at the Earth's...