Whats-New updates for v3.15.0rc0 . (#6986)

Author: trexfeathers

docs/src/whatsnew/latest.rst docs/src/whatsnew/3.15.rstdocs/src/whatsnew/latest.rst renamed to docs/src/whatsnew/3.15.rst

@@ -1,21 +1,45 @@
 .. include:: ../common_links.inc
 
-|iris_version| |build_date| [unreleased]
-****************************************
+v3.15 (17 Mar 2026 [release candidate])
+***************************************
 
 This document explains the changes made to Iris for this release
 (:doc:`View all changes <index>`.)
 
 
-.. dropdown:: |iris_version| Release Highlights
+.. dropdown:: v3.15 Release Highlights
    :color: primary
    :icon: info
    :animate: fade-in
    :open:
 
-   The highlights for this major/minor release of Iris include:
+   The highlights for this minor release of Iris include:
 
-   * N/A
+   * Overhauling the user documentation structure to maximise discoverability
+     and engagement with user needs going forward.
+
+   * NIMROD loader improvements to expand the types of NIMROD files Iris can load.
+
+   * Documentation page explaining how to access files in S3 buckets.
+
+   * Compatibility with Pandas version 3.
+
+   * Several large pieces of work **behind the scenes** to put Iris in the best
+     possible place for the future. To be continued!
+
+     * Investigating how Iris can provide native `Zarr`_ loading and saving
+       (beyond what is already possible via `ncdata`_).
+
+     * Completed a 2-year project converting all tests from unittest to pytest,
+       including compliance with the Ruff `PT` standard.
+
+     * In-progress work to fully support arrays of characters/strings.
+
+     * Investigating how Iris can integrate with the `Pint`_ units library, to
+       increase interoperability with the wider scientific Python ecosystem.
+
+     * Layout groundwork for making Iris fully Pip-installable, reducing the
+       dependency footprint and improving handling of optional dependencies.
 
    And finally, get in touch with us on :issue:`GitHub<new/choose>` if you have
    any issues or feature requests for improving Iris. Enjoy!
@@ -60,19 +84,27 @@ This document explains the changes made to Iris for this release
 🐛 Bugs Fixed
 =============
 
-#. N/A
+#. `@ukmo-ccbunney`_ changed formatting of numpy scalars attributes when generating a
+   Cube/Coord summary to use ``str`` representation instead of ``repr``.
+   (:pull:`6966`, :issue:`6692`)
 
 
 💣 Incompatible Changes
 =======================
 
-#. N/A
+#. `@hsteptoe`_ and `@ESadek-MO`_ (reviewer) disabled the ``copy`` behaviour
+   across :mod:`iris.pandas`, as it is incompatible with Pandas v3 (see
+   `New pandas v3 copy behaviour`_). The parameter is still present, to help
+   mitigate disruption, but now marked for deprecation. (:pull:`6948`,
+   :issue:`6761`)
 
 
 🚀 Performance Enhancements
 ===========================
 
-#. N/A
+#. Note that ``libnetcdf`` version 4.10.0 (released 25th Feb 2026) improves
+   NetCDF loading and saving performance, measured between 20-40% in Iris'
+   benchmarks (:issue:`6984`).
 
 
 🔥 Deprecations
@@ -89,7 +121,8 @@ This document explains the changes made to Iris for this release
 🔗 Dependencies
 ===============
 
-#. N/A
+#. `@hsteptoe`_ and `@ESadek-MO`_ (reviewer) made :mod:`iris.pandas`
+   interoperability compatible with pandas v3. (:pull:`6948`, :issue:`6761`)
 
 
 📚 Documentation
@@ -103,7 +136,8 @@ This document explains the changes made to Iris for this release
 #. :user:`bjlittle` added the ``:user:`` `extlinks`_ ``github`` user convenience.
    (:pull:`6931`)
 
-#. `@pp-mo`_ added a page on how to access datafiles in S3 buckets.
+#. `@pp-mo`_ added a page on how to access datafiles in S3 buckets:
+   :doc:`/user_manual/tutorial/s3_io`.
    (:issue:`6374`, :pull:`6951`)
 
 #. `@trexfeathers`_, `@stephenworsley`_, `@ESadek-MO`_ and `@tkknight`_ reorganised **all**
@@ -144,10 +178,6 @@ This document explains the changes made to Iris for this release
 
 #. `@hsteptoe`_ and `@ESadek-MO`_ (reviewer) added static type hinting to :mod:`iris.pandas`. (:pull:`6948`)
 
-#. `@ukmo-ccbunney`_ changed formatting of numpy scalars attributes when generating a
-   Cube/Coord summary to use ``str`` representation instead of ``repr``.
-   (:pull:`6966`, :issue:`6692`)
-
 .. comment
     Whatsnew author names (@github name) in alphabetical order. Note that,
     core dev names are automatically included by the common_links.inc:
@@ -160,3 +190,6 @@ This document explains the changes made to Iris for this release
 
 .. _New pandas v3 copy behaviour: https://pandas.pydata.org/docs/whatsnew/v3.0.0.html#consistent-copy-view-behaviour-with-copy-on-write
 .. _SPEC0 Minimum Supported Dependencies: https://scientific-python.org/specs/spec-0000/
+.. _Zarr: https://zarr.dev/
+.. _ncdata: https://github.com/SciTools/ncdata
+.. _Pint: https://github.com/hgrecco/pint

docs/src/whatsnew/index.rst

@@ -6,13 +6,13 @@
 What's New in Iris
 ------------------
 
-.. include:: latest.rst
+.. include:: 3.15.rst
 
 .. toctree::
    :maxdepth: 1
    :hidden:
 
-   latest.rst
+   3.15.rst
    3.14.rst
    3.13.rst
    3.12.rst