Populate whatsnew 2.2

docs/iris/src/whatsnew/2.2.rst

@@ -1,22 +1,22 @@
-What's New in Iris 2.2.0
+What's New in Iris 2.2
 ************************
 
-:Release: 2.2.0a0
+:Release: 2.2.0
 :Date:
 
 
-This document explains the new/changed features of Iris in the alpha release
-of version 2.2.0
+This document explains the new/changed features of Iris in the release
+of version 2.2
 (:doc:`View all changes <index>`).
 
 
-Iris 2.2.0 Features
+Iris 2.2 Features
 ===================
 .. _showcase:
 
 .. admonition:: 2-Dimensional Coordinate Plotting
 
-  The iris plot functions :func:`~iris.plot.pcolor` and
+  The Iris plot functions :func:`~iris.plot.pcolor` and
   :func:`~iris.plot.pcolormesh` now accommodate the plotting of 2-dimensional
   coordinates as well as 1-dimensional coordinates.
 
@@ -25,11 +25,80 @@ Iris 2.2.0 Features
   contiguous, or the cube's data must be masked at the discontiguities in
   order to avoid plotting errors.
 
-  The iris plot functions :func:`iris.plot.quiver` has been added, and this
+  The Iris plot function :func:`iris.plot.quiver` has been added, and this
   also works with 2-dimensional plot coordinates.
 
 .. admonition:: 2-Dimensional Grid Vectors
 
-  The iris functions :func:`iris.analysis.cartography.gridcell_angles` and
+  The Iris functions :func:`iris.analysis.cartography.gridcell_angles` and
   :func:`iris.analysis.cartography.rotate_grid_vectors` have been added,
   allowing you to convert gridcell-oriented vectors to true-North/East ones.
+
+.. admonition:: NetCDF Data Variable Chunk Sizes
+
+  NetCDF data variable chunk sizes are now utilised at load time for
+  significant performance improvements.
+
+* The :class:`iris.fileformats.um.FieldCollation` objects, which are passed
+  into load callbacks when using
+  :func:`iris.fileformats.um.structured_um_loading`, now
+  have the additional properties:
+  :data:`iris.fileformats.um.FieldCollation.data_filepath` and
+  :data:`iris.fileformats.um.FieldCollation.data_field_indices`.
+  These provide the file locations of the original data fields, which are
+  otherwise lost in the structured loading process.
+
+* :func:`iris.util.reverse` can now be used to reverse a cube by specifying
+  one or more coordinates.
+
+* Time mean fields can now be saved to PP files as a cell method.
+
+* Cube aggregators :func:`iris.analysis.MIN`, :func:`iris.analysis.MAX`,
+  :func:`iris.analysis.SUM` and :func:`iris.analysis.COUNT` now perform lazy
+  aggregation by utilizing dask.
+
+* Error messages thrown upon failed addition of an
+  :class:`~iris.aux_factory.AuxCoordFactory` now include the name of the
+  required (but absent) coordinate as well as the name of the cube.
+
+* The function :func:`iris.util.find_discontiguities` can be used to check for
+  discontiguities in the bounds arrays of cube coordinates.  Additionally,
+  discontiguous points in coordinates can be explicitly masked
+  using another new feature :func:`iris.util.mask_cube`.
+
+
+Iris 2.2 Dependency updates
+=============================
+
+* Iris is now using the latest version release of dask (currently 0.19.3)
+
+* Proj4 has been temporarily pinned to version < 5 while problems with the
+  Mollweide projection are addressed.
+
+* Matplotlib has been pinned to version < 3 temporarily while we account for
+  its changes in all SciTools libraries.
+
+
+Bugs Fixed
+==========
+
+* The bug has been fixed that prevented printing time coordinates with bounds
+  when the time coordinate was measured on a long interval (that is, ``months``
+  or ``years``).
+
+* "Gracefully filling..." warnings are now only issued when the coordinate or
+  bound data is actually masked.
+
+* Iris can now correctly unpack a column of header objects when saving a
+  pandas DataFrame to a cube.
+
+
+Documentation Changes
+=====================
+
+* Iris' `INSTALL` document has been updated to include guidance for running
+  tests.
+
+* A link has been added to the Developers' Guide to make it easier to find the
+  Pull Request Check List.
+