# Tracers and mass fixers?

**URL:** <https://forum.ecmwf.int/t/tracers-and-mass-fixers/12149>\
**Category:** OpenIFS\
**Tags:** openifs-43r3, openifs-atmospheric-composition, openifs-tracers\
**Created:** [16 November 2020 16:50 UTC](https://forum.ecmwf.int/t/tracers-and-mass-fixers/12149 "2020-11-16T16:50:54Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Etienne\_Tourigny](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/e/50afbb/32.png) [@Etienne\_Tourigny](https://forum.ecmwf.int/u/Etienne_Tourigny)\
**Post date:** [16 November 2020 16:50 UTC](https://forum.ecmwf.int/t/tracers-and-mass-fixers/12149/1 "2020-11-16T16:50:54Z")

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Dear all

please excuse my ignorance on this topic, but I would like to know which (if any) GHG and aerosol tracers and which mass fixers are supported in openifs43r3?

I am unsure if the page&nbsp;[How to control mass conservation in OpenIFS](https://confluence.ecmwf.int/display/OIFS/How+to+control+mass+conservation+in+OpenIFS)&nbsp;is outdated since it mentions Cycle 38r1&nbsp;:&nbsp;The version of OpenIFS based on Cycle 38r1 has a limited set of "mass-fixers" available. More recent versions of IFS have improved options for mass conservation.

thanks! Etienne

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**Author:** ![Etienne\_Tourigny](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/e/50afbb/32.png) [@Etienne\_Tourigny](https://forum.ecmwf.int/u/Etienne_Tourigny)\
**Post date:** [17 November 2020 09:12 UTC](https://forum.ecmwf.int/t/tracers-and-mass-fixers/12149/2 "2020-11-17T09:12:53Z")

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Found some information about oifs40r1 in other OpenIFS forums, will continue the discussion there.

[Chemical tracer transport in OpenIFS](https://prod.ecmwf-forum-prod.compute.cci2.ecmwf.int/t/chemical-tracer-transport-in-openifs/12168)

[Recommendations for mass fixers in OpenIFS?](https://prod.ecmwf-forum-prod.compute.cci2.ecmwf.int/t/recommendations-for-mass-fixers-in-openifs/12164)&nbsp;