# Negative humidity fixer

**URL:** <https://forum.ecmwf.int/t/negative-humidity-fixer/12096>\
**Category:** OpenIFS\
**Tags:** openifs-43r3, openifs-physics-parametrizations\
**Created:** [19 March 2020 14:38 UTC](https://forum.ecmwf.int/t/negative-humidity-fixer/12096 "2020-03-19T14:38:32Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Try\_Gve](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/t/b3f665/32.png) [@Try\_Gve](https://forum.ecmwf.int/u/Try_Gve)\
**Post date:** [19 March 2020 14:38 UTC](https://forum.ecmwf.int/t/negative-humidity-fixer/12096/1 "2020-03-19T14:38:32Z")

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Hi. We are doing a "sensitivity analysis" exercise investigating the impact on turning on and off various parametrization schemes in the OpenIFS framework. In that regards, I have played around with the Negative Humidity Fixer (LEQNGT). I am however wondering, what is this scheme actually doing? I searched around but did not find any answer to my question. I thought the scheme was supposed to not allow negative values of Relative Humidity (i.e. fixing negative values to zero) and also fix values \> 100% in Spherical Harmonics, but when running the model with the scheme on and off it yields both negative values and values \>100.

T

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**Author:** ![Glenn\_Carver](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/g/e495f1/32.png) [@Glenn\_Carver](https://forum.ecmwf.int/u/Glenn_Carver)\
**Post date:** [20 March 2020 13:20 UTC](https://forum.ecmwf.int/t/negative-humidity-fixer/12096/2 "2020-03-20T13:20:45Z")

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Hi,

There is a previous forum post about humidity values exceeding 100%, which may be useful. You can find it here:

Relative humidity in OpenIFS output.

G.