# Precipitation in the ocean **URL:** \ **Category:** Earth System\ **Created:** [27 August 2024 07:35 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108 "2024-08-27T07:35:28Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![dramauh](https://avatars.discourse-cdn.com/v4/letter/d/c5a1d2/32.png) [@dramauh](https://forum.access-hive.org.au/u/dramauh)\ **Post date:** [27 August 2024 07:35 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108/1 "2024-08-27T07:35:28Z")
Dear Community, I am trying to map the net precipitation into the ocean. Does anyone know how ACCESS-CM interpolates the precipitation into the ocean grid? Thanks in advance for your help. Kind regards, Estanislao ---
**Author:** ![anton](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/anton/32/1836_2.png) [@anton](https://forum.access-hive.org.au/u/anton)\ **Post date:** [27 August 2024 23:20 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108/2 "2024-08-27T23:20:16Z")
Hi Estanisloa Assuming we are talking about ACCESS-CM2, coupling fields (incl precipitation) are remapped using a first-order conservative remapping. The fields are transferred between the atmosphere and sea-ice components first, and then the sea-ice model captures any precipitation over sea-ice and passes the remainder to the ocean component. There are some details of this in the Bi et al 2020 [paper](https://www.publish.csiro.au/es/pdf/ES19040). If you are looking at raw MOM output, it might be the ‘lprec’ and ‘fprec’ fields for liquid and solid precipitation respectively. If you are looking at CMIP6 fields, I am not sure what the field would be called (`pr` includes precipitation over all land/ ocean / sea ice ). Anton ---
**Author:** ![dramauh](https://avatars.discourse-cdn.com/v4/letter/d/c5a1d2/32.png) [@dramauh](https://forum.access-hive.org.au/u/dramauh)\ **Post date:** [28 August 2024 01:30 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108/3 "2024-08-28T01:30:35Z")
Hi Anton, thank you so much for your reply. It helps a lot. If the precipitation falls on the seaice, do you know if the model has a threshold of ice concentration for leakage or I should do something like pr\*(1-sic)? Thanks again for your help. Kind regards, Estanislao ---
**Author:** ![anton](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/anton/32/1836_2.png) [@anton](https://forum.access-hive.org.au/u/anton)\ **Post date:** [28 August 2024 01:52 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108/4 "2024-08-28T01:52:34Z")
I don’t think CM2 has a mechanism for drainage through sea-ice, it’s just freeze/melt. So correcting for ocean\_area fraction will give precipitation entering the ocean. (Noting there is also runoff, melt, freezing, evaporation etc which transfer in/out of the ocean). ---
**Author:** ![anton](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/anton/32/1836_2.png) [@anton](https://forum.access-hive.org.au/u/anton)\ **Post date:** [28 August 2024 03:03 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108/5 "2024-08-28T03:03:09Z")
Oh `pr` will be saved on the atmosphere grid, and `siconc` will be on the ocean grid, so doing that calculation is not straightforward. ---
**Author:** ![dramauh](https://avatars.discourse-cdn.com/v4/letter/d/c5a1d2/32.png) [@dramauh](https://forum.access-hive.org.au/u/dramauh)\ **Post date:** [28 August 2024 03:18 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108/6 "2024-08-28T03:18:00Z")
Hi Anton, you are right, thats why I was asking about the remapping. I have used cdo to conservative remap the pr into the ocean. The comparison revealed about 2% of monthly bias. ---
**Author:** ![anton](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/anton/32/1836_2.png) [@anton](https://forum.access-hive.org.au/u/anton)\ **Post date:** [28 August 2024 03:30 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108/7 "2024-08-28T03:30:51Z")
> The comparison revealed about 2% of monthly bias. bias compared to what ? ---
**Author:** ![dramauh](https://avatars.discourse-cdn.com/v4/letter/d/c5a1d2/32.png) [@dramauh](https://forum.access-hive.org.au/u/dramauh)\ **Post date:** [28 August 2024 04:01 UTC](https://forum.access-hive.org.au/t/precipitation-in-the-ocean/3108/8 "2024-08-28T04:01:29Z")
I computed the total flux into the ocean so sum(pr x areacella x ocemask) and sum(pr\_remap x areacello x mask). Then i used the ration between these two.