Removing some branches on this repo?

[nbren12]

There are a lot of branches on this repo many which are presumably out of date. Should we close some of them? Here is a listing of the current branches

$ for k in `git branch -a | perl -pe s/^..//`; do echo -e `git show --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" $k -- | 
2021-03-30 10:45:14 -0700 18 minutes ago        remotes/origin/mp-changes-1
2021-03-28 07:54:18 -0400 2 days ago    remotes/origin/spack
2021-03-26 08:35:57 -0400 4 days ago    remotes/origin/fix-coarse-z
2021-03-25 16:30:36 -0400 5 days ago    remotes/origin/eddy-fluxes
2021-03-16 13:55:38 -0700 2 weeks ago   remotes/origin/ubuntu-20.04
2021-03-15 23:47:02 +0000 2 weeks ago   remotes/origin/update-fv3config
2021-03-11 23:06:05 +0000 3 weeks ago   remotes/origin/feature/column-nudging-diagnostics
2021-03-09 11:38:19 -0800 3 weeks ago   remotes/origin/remote-caching
2021-03-05 15:39:55 -0800 4 weeks ago   remotes/origin/serialize_physics
2021-02-19 15:15:40 +0000 6 weeks ago   remotes/origin/split-update_atmos_radiation_physics
2021-02-01 15:46:45 +0000 8 weeks ago   remotes/origin/serialization/d2a2c-exp--2
2021-01-31 05:28:43 +0000 8 weeks ago   remotes/origin/serialization/original-target
2021-01-13 07:25:09 +0000 3 months ago  remotes/origin/serialization/d2a2c-npt-c12-54ranks
2021-01-13 04:58:59 +0000 3 months ago  remotes/origin/debug/loudplease
2021-01-06 06:11:16 +0000 3 months ago  remotes/origin/serialize/c48_54
2020-12-14 15:18:19 -0500 4 months ago  remotes/origin/gaea
2020-12-10 21:06:38 +0000 4 months ago  remotes/origin/prognostic-tke
2020-11-17 14:39:11 -0800 4 months ago  remotes/origin/better-trigger
2020-10-16 12:21:07 +0000 6 months ago  remotes/origin/fix-sst-cycling
2020-10-15 21:28:47 -0700 6 months ago  remotes/origin/serializedata/baroclinic_exp
2020-10-12 19:29:13 -0700 6 months ago  remotes/origin/serialization/edge_interp
2020-10-12 16:01:52 -0700 6 months ago  remotes/origin/disable-convection-tendency
2020-10-12 12:27:45 -0700 6 months ago  remotes/origin/serialization/another_timestep
2020-10-12 12:13:28 -0700 6 months ago  remotes/origin/serialization-exp/splits
2020-10-09 10:54:43 -0700 6 months ago  remotes/origin/serializedata/baroclinic
2020-10-09 10:00:59 -0700 6 months ago  remotes/origin/feature/ubuntu20_openmpi4
2020-09-25 14:07:04 -0700 6 months ago  remotes/origin/feature/single_dockerfile_fork
2020-09-14 17:02:43 -0400 7 months ago  remotes/origin/feature/wrapper-testing
2020-08-27 16:43:58 -0700 7 months ago  remotes/origin/d2a2-for-c12-54ranks
2020-08-24 15:43:29 -0700 7 months ago  remotes/origin/serialize_compute_aam
2020-08-20 03:49:51 +0000 7 months ago  remotes/origin/feature/multiple_MPI_support
2020-08-17 23:17:12 +0000 8 months ago  remotes/origin/ml-emulation
2020-07-07 16:58:51 -0700 9 months ago  remotes/origin/subtree/fv3
2020-07-02 08:22:30 -0700 9 months ago  remotes/origin/subtree/fms
2020-06-23 11:37:33 -0700 9 months ago  remotes/origin/feature/simplify_ser_small
2020-06-04 10:46:23 -0700 10 months ago remotes/origin/fillz
2020-06-02 13:54:29 -0700 10 months ago remotes/origin/serialization/grid
2020-05-14 17:09:54 -0700 11 months ago remotes/origin/cs_profile_intermediate
2020-01-28 13:30:02 -0800 1 year, 2 months ago  remotes/origin/feature/restart
2020-01-27 15:04:43 -0800 1 year, 2 months ago  remotes/origin/fix/reference_name