# \#openifs-ifsdata

**URL:** https://forum.ecmwf.int/tag/openifs-ifsdata/124.md

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## [Are vtables actually needed?](https://forum.ecmwf.int/t/are-vtables-actually-needed/12187)

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**Author:** [@Joakim\_Kjellsson](https://forum.ecmwf.int/u/Joakim_Kjellsson)\
**Replies:** 3\
**Last updated:** [22 February 2021 12:39 UTC](https://forum.ecmwf.int/t/are-vtables-actually-needed/12187 "2021-02-22T12:39:42Z")

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Hi all I always link rtables and vtables folders in my run directory when I run OpenIFS, but I just tried to run without vtables and it still works. I've dug into the code and I can't find that vtable files, e.g. vtabl…

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## [Changing CO2 concentration in openIFS to rcp scenarions](https://forum.ecmwf.int/t/changing-co2-concentration-in-openifs-to-rcp-scenarions/12102)

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**Author:** [@Glenn\_Carver](https://forum.ecmwf.int/u/Glenn_Carver)\
**Replies:** 11\
**Last updated:** [17 November 2020 13:36 UTC](https://forum.ecmwf.int/t/changing-co2-concentration-in-openifs-to-rcp-scenarions/12102 "2020-11-17T13:36:34Z")

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The CO2 concentration (and other GHG concentrations) in openIFS is controlled via a couple of switches. In the climate data directory, you find the files CO2CLIM and GCO2CLIM. The CO2CLIM and GCO2CLIM files however only…