Citations and conditions of use ========== Conditions of use ------------- CHEEREIO is completely free and provided under a highly permissive MIT license. That said, we have a few requests if you use CHEEREIO: #. **Don't be a stranger**: Send me an email about how you are using CHEEREIO (andrew.pendergrass [at] duke [dot] edu). This helps me decide future development priorities, and will help me better support you through the inevitable challenges that will emerge in data assimilation applications. #. **Cite appropriately**: If you are submitting a paper for publication, see the below :ref:`appropriate citations` section for a list of references that have introduced CHEEREIO features. Please cite all papers that introduce features you use (in addition to the original 2023 CHEEREIO paper) as a way of recognizing efforts from the community. #. **Ask for help, preferably through a GitHub issue**: I am happy to help and I usually reply within one working day. All problems and questions, no matter how minor, should reported by opening an `issue `__ on Github, as this will allow all users to see the solution. You can also email me. #. **If you have gotten significant help using CHEEREIO, consider offering coauthorship**. Co-authorship is not a condition of CHEEREIO use. We only ask that you cite papers appropriately. However, if you've gotten significant support on debugging CHEEREIO, interpreting output, or introducing new features, consider offering co-authorship to those who helped you. #. **Offer your contributions to the community** by making a GitHub pull request. If you've added a new observation operator or otherwise made code adjustments, be in touch via email and make a pull request on GitHub. This will allow me to add your code to a future CHEEREIO release; I'll also update the citation section so that your efforts are recognized by future users of your code. If you need help making a pull request, just send an email to andrew.pendergrass [at] duke [dot] edu. .. _appropriate citations: CHEEREIO papers to cite ----------------------------- All CHEEREIO users should cite the original CHEEREIO paper in any publication: Pendergrass, D. C., Jacob, D. J., Nesser, H., Varon, D. J., Sulprizio, M., Miyazaki, K., & Bowman, K. W. (2023). CHEEREIO 1.0: A versatile and user-friendly ensemble-based chemical data assimilation and emissions inversion platform for the GEOS-Chem chemical transport model. Geoscientific Model Development, 16(16), 4793–4810. https://doi.org/10.5194/gmd-16-4793-2023 All CHEEREIO users should also cite the original LETKF paper in any publication: Hunt, B. R., Kostelich, E. J., & Szunyogh, I. (2007). Efficient data assimilation for spatiotemporal chaos: A local ensemble transform Kalman filter. Physica D: Nonlinear Phenomena, 230(1), 112–126. https://doi.org/10.1016/j.physd.2006.11.008 CHEEREIO users that use TCCON or TROPOMI CO (version 1.4+) should cite the following paper: Voshtani, S., Jones, D. B. A., Wunch, D., Pendergrass, D. C., Wennberg, P. O., Pollard, D. F., Morino, I., Ohyama, H., Deutscher, N. M., Hase, F., Sussmann, R., Weidmann, D., Kivi, R., García, O., Té, Y., Chen, J., Anderson, K., Stevens, R., Kondragunta, S., … Murata, I. (2025). Quantifying CO emissions from boreal wildfires by assimilating TROPOMI and TCCON observations. EGUsphere, 1–60. https://doi.org/10.5194/egusphere-2025-858 CHEEREIO users that use TROPOMI CH\ :sub:`4`, lognormal errors, or ObsPack should cite the following paper: Pendergrass, D. C., Jacob, D. J., Balasus, N., Estrada, L., Varon, D. J., East, J. D., He, M., Mooring, T. A., Penn, E., Nesser, H., & Worden, J. R. (2025). Trends and seasonality of 2019–2023 global methane emissions inferred from a localized ensemble transform Kalman filter (CHEEREIO v1.3.1) applied to TROPOMI satellite observations. EGUsphere, 1–26. https://doi.org/10.5194/egusphere-2025-1554