diff --git a/environment.yml b/environment.yml
index 1ad8343..8e0e753 100644
--- a/environment.yml
+++ b/environment.yml
@@ -17,7 +17,7 @@ dependencies:
   - scipy
   - numba
   - numpy>=1.21 # numpy.typing
-  - matplotlib>=3.8
+  - matplotlib>=3.9
   - mpi4py
   - pyarrow
   - pytz
diff --git a/pyproject.toml b/pyproject.toml
index 63217fa..404a90c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -22,7 +22,7 @@ readme = "README.md"
 requires-python = '>=3.9' # 3.8 -> scipy
 dependencies = [
     "colored-traceback", "fiona", "geopandas",
-    "jigsawpy", "matplotlib>=3.8", "netCDF4", "numba",
+    "jigsawpy", "matplotlib>=3.9", "netCDF4", "numba",
     "numpy>=1.21", # introduce npt.NDArray
     "pyarrow", "rtree", "pyproj>=3.0", "rasterio", "scipy",
     "shapely", "triangle", "typing_extensions", "utm",