Draft for release notes - #7348

e.g. Landlab coupling?

@danieldouglas92 what do you think? Is it "usable"?

potential things to add:

• CPO/fabric functionality including generalized CPO algorithm, clinopyroxene example, Olivine D-type fabric, and CPO cookbook.

• Reaction kinetics implementation.

• FastScape: sea-level and climate-dependent erosion parameters, improved checkpoint/restart behavior, and
  additional topography support.

• Numerical robustness and performance. The global-coarsening GMG Stokes solver now supports periodic and rotationally periodic boundaries, hanging nodes, Q1-projected viscosity, and operation without material averaging. Additional improvements include configurable handling of iterative Stokes solver failures, discontinuous compositional fields with melt transport, and pressure-gradient-based Darcy advection.

What is there works and is "usable" if you know how to use it, but I think we are missing a lot of documentation explaining how to use it and what the limitations currently are.

I don't see the risk in including the changelog entry that says "Added: A mesh deformation plugin which couples to the landscape evolution library Landlab to deform the surface of an ASPECT model." If it's appropriate though we can add something in the documentation that states that this is on-going development work?

We could also formulate it very cautiously, e.g. "ASPECT now has an interface to couple to general external codes to deform the surface mesh."

Or we combine it with all the improvements to Fastscape:

"Support for surface evolution has been significantly extended: Fastscape can now .... . Preliminary support for the Landlab surface evolution library is available."

To Timo's comments:

Reaction kinetics implementation.

I kind of included that in: A new composition type is available which is used to keep track of the state of reactions, for example in models considering reaction kinetics. A cookbook illustrating reaction kinetics was added.
I didnt want to mention too much of the concrete reaction kinetic implementations, because they are not actually included in any material models at the moment.

All the other suggestions are good ones, I will prepare an updated version.

"Support for surface evolution has been significantly extended: Fastscape can now .... . Preliminary support for the Landlab surface evolution library is available."

I think this makes sense!

Version 2

Good catch, I was reshuffling and combining entries and must have missed him.

Landlab is mentioned at the end of the first entry, we didnt want to emphasize it, because it is not well documented yet.