From 189883a2e2cab73db6afb33d46bc886b03318080 Mon Sep 17 00:00:00 2001
From: Trey Stafford <trey.stafford@colorado.edu>
Date: Mon, 16 Sep 2024 11:34:26 -0600
Subject: [PATCH] Add CHANGELOG and dev doc note about `match-cdrv4`

---
 CHANGELOG.md       |  7 +++++++
 doc/development.md | 11 +++++++++++
 2 files changed, 18 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f689dccd..9deb591c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+# match-cdrv4 (commit 87271ec)
+
+* `match-cdrv4` tag marks the commit at which this code supports replicating the
+  behavior of CDRv4 at 25km resolution. This is useful for comparison
+  purposes. Future commits will remove support for producing CDRv4 in favor of
+  the improvements and bugfixes provided by CDRv5.
+
 # v0.2.0
 
 * Produce 25km CDR instead of 12.5km.
diff --git a/doc/development.md b/doc/development.md
index 923a7bad..b77ad12c 100644
--- a/doc/development.md
+++ b/doc/development.md
@@ -163,3 +163,14 @@ When making a new release of G02202 based on this code:
   archive containing the `seaice_ecdr`, `pm_icecon`, and `pm_tb_data`
   repositories and ancillary data. This `.zip` package should then be sent to
   NOAA for archival.
+
+
+### Replicating CDRv4 results
+
+There are a number of improvements and bug fixes that have been made since the
+CDRv4. To produce CDRv4-compatible results with this code, checkout the
+`match-cdrv4` tag (commit 87271ec):
+
+```
+git checkout match-cdrv4
+```