# Carbon: modelling works, but results are incorrect (only underground biomass) **URL:** \ **Category:** Software Support\ **Tags:** carbon\ **Created:** [March 5, 2024, 3:04pm UTC](https://community.naturalcapitalalliance.org/t/carbon-modelling-works-but-results-are-incorrect-only-underground-biomass/4522 "2024-03-05T15:04:04Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Laurie](https://avatars.discourse-cdn.com/v4/letter/l/13edae/32.png) [@Laurie](https://community.naturalcapitalalliance.org/u/Laurie)\ **Post date:** [March 5, 2024, 3:04pm UTC](https://community.naturalcapitalalliance.org/t/carbon-modelling-works-but-results-are-incorrect-only-underground-biomass/4522/1 "2024-03-05T15:04:04Z")
Hi everyone, I need your help to solve a problem for which I can’t find the solution. I’ve searched the forum, but haven’t found an answer. This is the second time I’ve worked with this model and the first time I’ve encountered this problem. I entered my LULC (2020) and attached my carbon tank table (csv format). When I press “Run”, everything works. But it’s when I display the results on ArcGIS Pro that I see there’s been a problem with the calculation. It seems that only the underground biomass reservoir was taken into account in the modelling: the results range from 0.49 to 1.89 tc/ha, even though it’s a forest massif… my hypothesis is that the other reservoirs were not taken into account. Do you have a solution or have you already encountered this problem? If so, how did you solve it? I’ve also tried changing my C values in the reservoir table to “number” format instead of “standard” (csv file), but to nothing effect. Thanks in adavnce for your help, Laurie. ---
**Author:** ![swolny](https://yyz1.discourse-cdn.com/flex031/user_avatar/community.naturalcapitalalliance.org/swolny/32/181_2.png) [@swolny](https://community.naturalcapitalalliance.org/u/swolny)\ **Post date:** [March 5, 2024, 4:13pm UTC](https://community.naturalcapitalalliance.org/t/carbon-modelling-works-but-results-are-incorrect-only-underground-biomass/4522/2 "2024-03-05T16:13:50Z")
Hi Laurie - I have not seen this issue before. Can you send me your input data and I’ll take a look at it? [Here are instructions for creating a datastack](https://community.naturalcapitalalliance.org/t/an-easy-way-to-share-data-using-the-invest-workbench/3879). If it’s too large to attach here (or you would rather not attach it here), you can provide it via Dropbox, Google Drive or whatever you use. ~ Stacie ---
**Author:** ![Laurie](https://avatars.discourse-cdn.com/v4/letter/l/13edae/32.png) [@Laurie](https://community.naturalcapitalalliance.org/u/Laurie)\ **Post date:** [March 5, 2024, 5:55pm UTC](https://community.naturalcapitalalliance.org/t/carbon-modelling-works-but-results-are-incorrect-only-underground-biomass/4522/3 "2024-03-05T17:55:04Z")
Hi Stacie, Here you are: [invest\_carbon\_datastack.zip](https://community.naturalcapitalalliance.org/uploads/short-url/qtjVCtU9jNuOCe6N9GQgp6R0Hwy.zip) (2.4 MB) Maybe I missed a step or made a mistake, either when producing the lulc rasters or the csv file? I’ve tried a few things, thinking that would solve the problem, but I can’t see what I’ve missed. It’s just the result that surprises me, normally we should have much higher values of Tc/ha. Thanks again your help, Laurie. ---
**Author:** ![swolny](https://yyz1.discourse-cdn.com/flex031/user_avatar/community.naturalcapitalalliance.org/swolny/32/181_2.png) [@swolny](https://community.naturalcapitalalliance.org/u/swolny)\ **Post date:** [March 5, 2024, 6:41pm UTC](https://community.naturalcapitalalliance.org/t/carbon-modelling-works-but-results-are-incorrect-only-underground-biomass/4522/4 "2024-03-05T18:41:03Z")
Thanks for sending your inputs. The results look fine to me. Remember that the result values are given in tons per _ **pixel** _, not per hectare, and in your case pixels are 10x10 meters, so it’s a small area. You can sanity check the results by comparing _tot\_c\_cur.tif_ with the 4 carbon pool mappings that are in the _intermediate_ Workspace folder. Click on a pixel and add them up and I think you’ll find that the total values are correct. ~ Stacie ---
**Author:** ![system](https://canada1.discourse-cdn.com/flex031/uploads/naturalcapitalproject/original/2X/8/8d95591aa074da87ea0fdd61ca47c1c3c0588aa7.png) [@system](https://community.naturalcapitalalliance.org/u/system)\ **Post date:** [June 3, 2024, 6:41pm UTC](https://community.naturalcapitalalliance.org/t/carbon-modelling-works-but-results-are-incorrect-only-underground-biomass/4522/5 "2024-06-03T18:41:06Z")
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