From ed0418bdc9dd1dbebd05c12e04ddeb267c1768be Mon Sep 17 00:00:00 2001
From: owenlittlejohns <owen.m.littlejohns@nasa.gov>
Date: Wed, 11 Sep 2024 12:34:53 -0600
Subject: [PATCH] Release notes for v2024.09.0 (#9480)

---
 doc/whats-new.rst | 33 ++++++++++++---------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/doc/whats-new.rst b/doc/whats-new.rst
index b5e3ced3be8..4902db26cd1 100644
--- a/doc/whats-new.rst
+++ b/doc/whats-new.rst
@@ -15,15 +15,21 @@ What's New
     np.random.seed(123456)
 
 
-.. _whats-new.2024.07.1:
+.. _whats-new.2024.09.0:
 
-v2024.07.1 (unreleased)
------------------------
+v2024.09.0 (Sept 11, 2024)
+--------------------------
+This release drops support for Python 3.9, and adds support for grouping by :ref:`multiple arrays <groupby.multiple>`, while providing numerous performance improvements and bug fixes.
+
+Thanks to the 33 contributors to this release:
+Alfonso Ladino, Andrew Scherer, Anurag Nayak, David Hoese, Deepak Cherian, Diogo Teles Sant'Anna, Dom, Elliott Sales de Andrade, Eni, Holly Mandel, Illviljan, Jack Kelly, Julius Busecke, Justus Magin, Kai Mühlbauer, Manish Kumar Gupta, Matt Savoie, Maximilian Roos, Michele Claus, Miguel Jimenez, Niclas Rieger, Pascal Bourgault, Philip Chmielowiec, Spencer Clark, Stephan Hoyer, Tao Xin, Tiago Sanona, TimothyCera-NOAA, Tom Nicholas, Tom White, Virgile Andreani, oliverhiggs and tiago
 
 New Features
 ~~~~~~~~~~~~
 
-- Add :py:attr:`~core.accessor_dt.DatetimeAccessor.days_in_year` and :py:attr:`~core.accessor_dt.DatetimeAccessor.decimal_year` to the Datetime accessor on DataArrays. (:pull:`9105`).
+- Add :py:attr:`~core.accessor_dt.DatetimeAccessor.days_in_year` and
+  :py:attr:`~core.accessor_dt.DatetimeAccessor.decimal_year` to the
+  ``DatetimeAccessor`` on ``xr.DataArray``. (:pull:`9105`).
   By `Pascal Bourgault <https://github.com/aulemahal>`_.
 
 Performance
@@ -38,6 +44,8 @@ Performance
   By `Deepak Cherian <https://github.com/dcherian>`_.
 - Allow data variable specific ``constant_values`` in the dataset ``pad`` function (:pull:`9353``).
   By `Tiago Sanona <https://github.com/tsanona>`_.
+- Speed up grouping by avoiding deep-copy of non-dimension coordinates (:issue:`9426`, :pull:`9393`)
+  By `Deepak Cherian <https://github.com/dcherian>`_.
 
 Breaking changes
 ~~~~~~~~~~~~~~~~
@@ -61,11 +69,6 @@ Breaking changes
     zarr                    2.14      2.16
   ===================== =========  =======
 
-
-Deprecations
-~~~~~~~~~~~~
-
-
 Bug fixes
 ~~~~~~~~~
 
@@ -90,24 +93,12 @@ Bug fixes
   (:issue:`9408`, :pull:`9413`).
   By `Oliver Higgs <https://github.com/oliverhiggs>`_.
 
-Performance
-~~~~~~~~~~~
-
-- Speed up grouping by avoiding deep-copy of non-dimension coordinates (:issue:`9426`, :pull:`9393`)
-  By `Deepak Cherian <https://github.com/dcherian>`_.
-
-Documentation
-~~~~~~~~~~~~~
-
-
 Internal Changes
 ~~~~~~~~~~~~~~~~
 
 - Re-enable testing ``pydap`` backend with ``numpy>=2`` (:pull:`9391`).
   By `Miguel Jimenez <https://github.com/Mikejmnez>`_ .
 
-
-
 .. _whats-new.2024.07.0:
 
 v2024.07.0 (Jul 30, 2024)