# S5P\_L2\_CH4, ERROR: cannot keep non-existent variable CH4\_column\_number\_density\_avk

**URL:** https://forum.atmospherictoolbox.org/t/s5p-l2-ch4-error-cannot-keep-non-existent-variable-ch4-column-number-density-avk/519
**Category:** HARP
**Tags:** sentinel-5p
**Created:** [June 3, 2022, 11:15pm UTC](https://forum.atmospherictoolbox.org/t/s5p-l2-ch4-error-cannot-keep-non-existent-variable-ch4-column-number-density-avk/519 "2022-06-03T23:15:46Z")
**Posts on this page:** 1
**Showing post:** 2

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### Author: ![aggiedude](https://forum.atmospherictoolbox.org/user_avatar/forum.atmospherictoolbox.org/aggiedude/32/235_2.png) [@aggiedude](https://forum.atmospherictoolbox.org/u/aggiedude)
#### Post date: [June 6, 2022, 9:23pm UTC](https://forum.atmospherictoolbox.org/t/s5p-l2-ch4-error-cannot-keep-non-existent-variable-ch4-column-number-density-avk/519/2 "2022-06-06T21:23:25Z")

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> [@aggiedude](#):
>
> CH4\_column\_number\_density\_avk

nevermind…

According to this post,

> [@Keep averaging kernel variables](https://forum.atmospherictoolbox.org/t/keep-averaging-kernel-variables/447):
>
> Hello, I would like to compare S5P HCHO with model simulated results. For comparing simulated and observed results, I need averaging kernel. So I tried converting L2 tropospheric\_HCHO\_column\_number\_density\_avk variable into L3 grid by following code. However, running this code raised error. I also tried running this code without specifying variables in keep() parameter, but resulting L3 files do not contain tropospheric\_HCHO\_column\_number\_density\_avk variable. Is there a…

cant regrid averaging kernel variables

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