diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1221aac..5f56445 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,25 @@
 # Changelog
 
+## [0.9.0] - 2024-12-04
+
+### Added
+
+- Species: $O_3$, $CH_4$, PMO and Contrails
+
+### Limitations
+
+- Limited resolution of response surfaces and pending validation for species $O_3$, $CH_4$ and PMO
+- Stratospheric Water Vapor (SWV) not considered in this version
+- Contrails module: AirClim 2.1 methodology including simulations for $H_2$ from AHEAD project
+- Climate impact of longer species lifetimes in the stratosphere not considered
+- Overhanging effect on next year not considered for species lifetimes in the order of time step (year)
+
+### Updates
+
+- Change of versioning scheme to [semantic versioning](https://semver.org/)
+- Move repository directory
+- Integrate default configuration settings
+
 ## [2.8.3] - 2024-09-04
 
 ### Added
diff --git a/openairclim/__about__.py b/openairclim/__about__.py
index 8468588..24d9092 100644
--- a/openairclim/__about__.py
+++ b/openairclim/__about__.py
@@ -12,7 +12,7 @@
 
 
 __title__ = "OpenAirClim"
-__version__ = "2.8.3"
+__version__ = "0.9.0"
 __author__ = "OpenAirClim Team"
 __email__ = "stefan.voelk@dlr.de"
 __license__ = "Apache 2.0"