Fixed recipe_meehl20sciadv.yml for ESMValCore 2.3

[schlunma]

This PR fixes recipe_meehl20sciadv.yml by adding a missing fx_variables: areacella.

• Addresses parts of Test esmvalcore=2.3.0 with current batch of ESMValTool recipes #2198.

---

Before you get started

• ☝ Create an issue to discuss what you are going to do

Checklist

It is the responsibility of the author to make sure the pull request is ready to review. The icons indicate whether the item will be subject to the 🛠 Technical or 🧪 Scientific review.

• 🛠 This pull request has a descriptive title
• 🛠 Code is written according to the code quality guidelines
• 🛠 Documentation is available
• 🛠 Tests run successfully
• 🛠 The list of authors is up to date
• 🛠 Any changed dependencies have been added or removed correctly
• 🛠 All checks below this pull request were successful

New or updated recipe/diagnostic

• 🧪 Recipe runs successfully
• 🧪 Recipe is well documented
• 🧪 Figure(s) and data look as expected from literature
• 🛠 Provenance information has been added

---

To help with the number of pull requests:

• 🙏 We kindly ask you to review two other open pull requests in this repository

[schlunma]

@esmvalbot Please run recipe_meehl20sciadv.yml

[esmvalbot]

Since @schlunma asked, ESMValBot will run recipe recipe_meehl20sciadv.yml as soon as possible, output will be generated here

[esmvalbot]

ESMValBot is happy to report recipe recipe_meehl20sciadv.yml ran OK, output has been generated here

[schlunma]

@ESMValGroup/esmvaltool-coreteam can someone please quickly review and merge this? This adds 2 lines to recipe_meehl20sciadv.yml to fix it (it previously failed, see #2198). The bot ran fine 🎉

[bettina-gier]

Changes looks fine, output looks comparable to cited paper - all good!

[schlunma]

Thanks Tina!!

[bouweandela]

Good find @schlunma! I noticed that many more recipes are affected by this and opened issue ESMValGroup/ESMValCore#1265 to investigate.