diff --git a/src/geofabrics/dem.py b/src/geofabrics/dem.py
index cd40bb2d..b432c084 100644
--- a/src/geofabrics/dem.py
+++ b/src/geofabrics/dem.py
@@ -1711,7 +1711,9 @@ def add_coarse_dems(
                 .set_crs(self.catchment_geometry.crs["horizontal"])
             )
             coarse_dem_resolution = coarse_dem.rio.resolution()
-            coarse_dem_resolution = max(abs(coarse_dem_resolution[0]), abs(coarse_dem_resolution[1]))
+            coarse_dem_resolution = max(
+                abs(coarse_dem_resolution[0]), abs(coarse_dem_resolution[1])
+            )
             coarse_dem_bounds = coarse_dem.rio.bounds()
             coarse_dem_bounds = geopandas.GeoDataFrame(
                 {